Journals >Spectroscopy and Spectral Analysis
Contents
2013
Volume: 33 Issue 11
62 Article(s)
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Research Article
Asymmetric Control Method for Ion Shutter and the Resolution Improvement of Ion Mobility Spectrum
LIU Sheng, HUANG Chao-qun, SHEN Cheng-yin, and CHU Yan-nan
In order to change the driving mode of ion shutter, simplify the design of ion shutter driving power and improve the resolution of ion mobility spectrometry, a series of resistors were added to achieve asymmetric power supply of ion shutter, and the low voltage part was controlled to realize the function of ion shutterIn order to change the driving mode of ion shutter, simplify the design of ion shutter driving power and improve the resolution of ion mobility spectrometry, a series of resistors were added to achieve asymmetric power supply of ion shutter, and the low voltage part was controlled to realize the function of ion shutter. Two conditions in this mode, the effect of electric field in drift tube and the resolution and signal-to-noise ratio of ion mobility spectrum were analyzed. Aided by SIMION 7.0, the electric field distribution at both sides of ion shutter was simulated and compared. Electric field data of drift tube axis was calculated through the method of numerical solution of Laplace equation. Experiment has proved that: compared with floating ground driving power used in conventional ion mobility spectrometry, the driving mode was low cost, and the design of ion shutter driving power supply was simple, and the resolution of ion mobility spectrometry was enhanced significantly. The method can be used in measurement instrument or experimental device of ion mobility spectrometry..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 2881 (2013)
Analyzing Moiré Pattern Spectra Based on the Mutual Transform between Signals’ Waveform in Time Domain and Their Spectra in Frequency Space
SUN Tao, and SONG Yi-zhong
The mutual evolving processes of signals’ waveforms and their spectra were numerically analyzed in time and frequency domains. The purpose was to research the essential relation between the signals’ waveforms and their spectra. Then, the mutual transform principle was applied to analyze moiré pattern spectra, acquThe mutual evolving processes of signals’ waveforms and their spectra were numerically analyzed in time and frequency domains. The purpose was to research the essential relation between the signals’ waveforms and their spectra. Then, the mutual transform principle was applied to analyze moiré pattern spectra, acquiring phase distribution information of the pattern. The rectangular window function was used to simulate the mutual transform between the impulse signal and direct-current waveform. Many rectangular window signals with deferent widths were obtained by changing the window width. The unit impulse signal was obtained by changing the width down to zero, and the direct-current waveform obtained by changing the width up to ＋∞. For smart, quick, and easy implementation of discrete Fourier transforms to rectangular pulses and obtain signals’ spectra, a simple FFT system was worked out. With its calculating, the mutual evolving processes of signals’ waveforms and their spectra were tracked deeply. All signals here were transformed with it. As the result, first, the spectra of rectangular window signals were in the form of sampling function ［Sa(x)=sin(x)/x］. Second, with the change in the window’s width, the waveform of Sa(x) changed. Third, when the width decreased, the waveform of Sa(x) extended, and vibrated more slowly. It changed into direct-current waveform when the width decreased to zero. Last, when the width increased, the waveform of Sa(x) shranked, and vibrated faster. It changed into impulse waveform when the width increased to ＋∞. Signals’ waveforms were in mutual transforms between the time and frequency domain. The transforming essence was considered as that the frequency component principle in Fourier series theory is reflected in the frequency domain. According to the principle of mutual transforms between signals’ waveforms and their spectra, the first order spectrum of the moiré pattern was extracted out and normalized to a constant one when the moiré patterns were analyzed for acquiring their phase information. By the normalization, the moiré pattern should take on the sampling function model, which showed high contrast level. This new pattern was convenient for acquiring the phase information..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 2886 (2013)
Depth Selectivity by Using Polarization-Controlled Spectral Technique
FENG Xu, SUN Li-qun, and ZHANG En-yao
A continuous depth selectivity is examined by changing the state of polarization of the signal light, based on the orthogonal polarization spectral (OPS) microcirculation imaging system. Unlike the traditional OPS system, which could only rend a two dimensional image of a certain cross-section, the elliptically polarizA continuous depth selectivity is examined by changing the state of polarization of the signal light, based on the orthogonal polarization spectral (OPS) microcirculation imaging system. Unlike the traditional OPS system, which could only rend a two dimensional image of a certain cross-section, the elliptically polarized light controlled by the polarizer unit and the analyzer unit could do the microscopy refocusing without mechanically scanning the sample, as a result, the tissue information at different depths could be obtained. Because the proposed system matches the emission spectrum of the light source with the absorption spectrum of the erythrocyte, it has relatively high signal-to-noise ratio, and could be used to detect microcirculation. Imaging of a pork fat with a target is acquired, and the quantitative relationship between image contrast and the state of polarization is illustrated. The results show that from linearly to circularly polarized illumination, the image contrast gradually increases, and the maximum visible depth also increases. Finally, the auricle vessel of a nude mouse was detected by this polarization-controlled spectral imaging system. Through the experiment the feasibility of depth selectivity was proved. The proposed method provides new insights to microscopy refocusing of microcirculation..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 2891 (2013)
Tunneling Electroluminescence of the ZnO Nanorods/MEH-PPV Heterojunction Devices
YANG Yi-fan, ZHAO Su-ling, and GAO Song
In the present paper, zinc oxide nanorods (ZnO-NRs) were synthesized by the hydrothermal method at lower temperature and the polymer poly［2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene］ (MEH-PPV) were used to fabricate an electroluminescent device based on the structure of “ITO/ZnO-seed/ZnO-NRs/MEH-PPV/Al”. The meIn the present paper, zinc oxide nanorods (ZnO-NRs) were synthesized by the hydrothermal method at lower temperature and the polymer poly［2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene］ (MEH-PPV) were used to fabricate an electroluminescent device based on the structure of “ITO/ZnO-seed/ZnO-NRs/MEH-PPV/Al”. The measurement of current-voltage curve shows that it has a well rectifying characteristic. When a reverse bias exceeding 17 volts was applied to the ZnO-NRs/MEH-PPV heterojunction, both emissions of ZnO and MEH-PPV were detected. And the intensity of near ultraviolet emission from ZnO is stronger than that of the orange-red emission belonging to MEH-PPV. It was also shown that the light power is gradually promoted with the increase in the reverse bias. Unfortunately, although carriers were injected into the heterojunction under the positive bias, we could not get any emissions. Its mechanism is attributed to the specificity of the organic inorganic hybrid heterojunction and the nanometer effects of ZnO-NRs. It is concluded that tunneling electroluminescence happens in this prepared device under the reverse bias..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 2895 (2013)
Research on Electron Density in DC Needle-Plate Corona Discharge at Atmospheric Pressure
LIU Zhi-qiang, GUO Wei, LIU Tao-tao, WU Wen-shuo, and LIU Shu-min
Using needle-plate discharge device, corona discharge experiment was done in the atmosphere. Through photo of spot size of light-emitting area, the relationship between the voltage and thickness of corona layer was discussed. When the distance between tip and plate is fixed, the thickness of corona layer increases withUsing needle-plate discharge device, corona discharge experiment was done in the atmosphere. Through photo of spot size of light-emitting area, the relationship between the voltage and thickness of corona layer was discussed. When the distance between tip and plate is fixed, the thickness of corona layer increases with the increase in voltage; when the voltage is fixed, the thickness of corona layer decreases with the increase in the distance between tip and plate. As spectral intensity of N2(C3Πu)(337.1 nm）reflects high energy electron density, it was measured with emission spectrometry. The results show that high energy electron density is the biggest near the needle tip and the relationship between high energy electron density and voltage is basically linear increasing. Fixing voltage, high energy electron density decreases with the increase in the distance between tip and plate. When the voltage and the distance between tip and plate are fixed, the high energy electron density increases with the decrease in the curvature radius of needle tip. These results are of great importance for the study of plasma parameters of corona discharge..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 2900 (2013)
Study on Stable Process of Hexagon Pattern in Dielectric Barrier Discharge by Optical Emission Spectra
DONG Li-fang, ZHANG Chao, ZHANG Xin-pu, and ZHAO Long-hu
The effect of plasma parameters and excited states on the stable process of the hexagon pattern in a dielectric barrier discharge was studied by using optical emission spectra. It was found that the diameter of the discharge filament increases, the pattern gets more stable, and the color of the pattern changes from purThe effect of plasma parameters and excited states on the stable process of the hexagon pattern in a dielectric barrier discharge was studied by using optical emission spectra. It was found that the diameter of the discharge filament increases, the pattern gets more stable, and the color of the pattern changes from purple to gray with the increase in the voltage in dielectric barrier discharge in argon and air mixture. It indicates that the plasma excited states and parameters may be changed. To this end, the relative intensity of N2 and Ar spectral lines with respect to Ar Ⅰ 763.51 nm, the molecular vibration temperature, and the electron excitation temperature were measured with the change in the applied voltage. The results show that the relative intensity of N2 spectral lines decreases and that of Ar spectral lines increases with the increase in the voltage. And both the molecular vibration temperature and the electron excitation temperature increase. These phenomena indicate that the electron energy increases with the increase in the voltage. The increase of the stimulated argon atoms excited by higher energy electron leads to the increase in the diameters of the discharge filaments. Correspondingly, the areas of the wall charges deposited on the dielectric increase, which results in the enhancement of the interactions between filaments, and therefore the hexagon pattern becomes stable..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 2903 (2013)
Progress in the Research on Silicon-Nitrogen Based Phosphor for White LED
XU Guo-tang, LIANG Pei, WANG Le, DONG Qian-min, LIU Yang, and LI Xiao-yan
With the rapid development of white LED technology, the traditional YAG∶Ce3+ phosphor is difficult to meet the requirement due to the low color rendering and high color temperature. Using ultraviolet chip to stimulate the tri-phosphor has become an effective way for white LED, and it is urgent to develop novel tri-phosWith the rapid development of white LED technology, the traditional YAG∶Ce3+ phosphor is difficult to meet the requirement due to the low color rendering and high color temperature. Using ultraviolet chip to stimulate the tri-phosphor has become an effective way for white LED, and it is urgent to develop novel tri-phosphor with high-performance, especially for red light-emitting materials. Silicon-nitrogen based compounds contain the network structure composed of SiN4 tetrahedron, with higher chemical and thermal stability. Because of their diversity structures, these phosphors have a higher absorption efficiency in UV-blue region, and also, with the change of substrate and active ion, emission spectrum will cover the entire visible region, resulting in a higher light conversion efficiency and light color stability, coupled with the advantages of being not sensitive to the changes in temperature and drive current, etc. These studies will have a far-reaching impact on the development of white LED. In the present paper, we introduce the preparation and latest progress of silicon-nitrogen based phosphor, including the crystal structure, spectroscopic properties and application characteristics..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 2907 (2013)
Upconversion Emission from Er3+-Yb3+-Mo6+ Co-Doped ZrO2-Al2O3 Composites
XIAO Yu, CONG Yan, YANG Qi, ZHANG Zhi-hong, and LIU Peng-zu
A series of ZrO2-Al2O3 composites with various compositions were synthesized by co-precipitation method, and the upconversion emission properties of the Er-Yb-Mo co-doped ZrO2-Al2O3 composites were investigated in the present paper. The green UC emission in the Er-Yb-Mo co-doped ZrO2 is an order of magnitude stronger tA series of ZrO2-Al2O3 composites with various compositions were synthesized by co-precipitation method, and the upconversion emission properties of the Er-Yb-Mo co-doped ZrO2-Al2O3 composites were investigated in the present paper. The green UC emission in the Er-Yb-Mo co-doped ZrO2 is an order of magnitude stronger than that of the Er3+ single doped sample. When Al2O3 mixed in ZrO2 crystalline lattice with the most solid solubility, the crystalline ZrO2-Al2O3 solid solutions is tetragonal ZrO2. The UC emission is enhanced 8 times in the ZrO2-Al2O3 solid solutions, which is due to the oxygen vacancies generated in the solid solutions, increasing the energy transfer from Yb3+-MoO2-4 to Er3+..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 2913 (2013)
Crystal Structure and Upconversion Emission of Yb3+/Er3+-Co-Doped NaYF4 Nanocrystals
YAO Li-li, LUO Li, DONG Guo-shuai, and WANG Yin-hai
Yb3+/Er3+-co-doped cubic NaYF4 and Yb3+/Er3+/Gd3+-tri-doped hexagonal NaYF4 nanocrystals were synthesized by a modified coprecipitation method with ethylenediamine tetraacetic acid (EDTA) as chelating agent. The samples’ morphology, crystal phase and upconversion emission were measured with transmission electron microsYb3+/Er3+-co-doped cubic NaYF4 and Yb3+/Er3+/Gd3+-tri-doped hexagonal NaYF4 nanocrystals were synthesized by a modified coprecipitation method with ethylenediamine tetraacetic acid (EDTA) as chelating agent. The samples’ morphology, crystal phase and upconversion emission were measured with transmission electron microscope (TEM), X-ray diffraction patterns (XRD) and upconversion luminescence spectrum. TEM and XRD results showed that the phase transition from cubic to hexagonal was promoted through Gd3+ doping. It has been reported that the upconversion efficiency of hexagonal NaYF4 is higher than that of cubic NaYF4, however, the effect of crystal phase on upconversion luminescence has not been well understood. This work focuses analysis of measurement results to compare the effect of crystal phase on the crystal field energy splitting and upconversion emission intensity as well as emission color, and a mechanism of luminescence enhancement and color tunability are revealed. Strong visible upconversion luminescence can be seen clearly by the naked eyes in both cubic phase and hexagonal phase samples upon excitation by a 980 nm laser diode with power of 10 mW, consisting of green emissions centered at around 525/550 nm originating from the transitions of 2H11/2/4S3/2→4I15/2 and red emission at about 657 nm from 4F9/2 to 4I15/2 of Er3+ ions respectively. In comparison to cubic sample, the hexagonal phase sample presented much stronger and sharper upconversion luminescence, whose emission efficiency was enhanced 10 times with an additional transition of 2H9/2→4I13/2 at 557 nm, furthermore, the intensity ratio of red to green emission increased from 2∶1 to 3∶1. Doping NaYF4 nanocrystals with Gd3+ ions induced the hexagonal-to-cubic phase transition and thus decreased the crystal symmetry, consequently increased absorption cross-section and 4f—4f transition probabilities by relaxing forbidden selection rules, resulting in stronger emission. In the mean time, the decreasing unit-cell volume of the hexagonal phase increased the crystal field strength around the dopant ions and consequently led to that hexagonal phase samples present much sharper emission compared to cubic counterparts. It demonstrates that phase transition can tune crystal field energy splitting, luminescence intensity and emission color..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 2917 (2013)
Structure and Luminescence Properties of Ga2O3∶Cr3+ by Al Doping
WANG Xian-sheng, WAN Min-hua, WANG Yin-hai, ZHAO Hui, HU Zheng-fa, and LI Hai-ling
The Al doping gallate phosphor (Ga1-xAlx)2O3∶Cr3+ (x=0, 0.1, 0.2, 0.3, 0.4, 0.5) was synthesized by a high temperature solid-state reaction method. The X-ray diffractions show that the phase of the phosphors remains to be Ga2O3 structure with increase in the contents of Al3+ ion. Beside, the fact that the X-ray diffracThe Al doping gallate phosphor (Ga1-xAlx)2O3∶Cr3+ (x=0, 0.1, 0.2, 0.3, 0.4, 0.5) was synthesized by a high temperature solid-state reaction method. The X-ray diffractions show that the phase of the phosphors remains to be Ga2O3 structure with increase in the contents of Al3+ ion. Beside, the fact that the X-ray diffraction peak shifts towards big angles with increasing Al3+ ions content shows that Al3+ ions entered the Ga2O3 lattice. The peaks of the excitation spectra located at 258, 300, 410 and 550 nm are attributed to the band to band transition of the matrix, charge transfer band transition, and 4A2→4T1 and 4A2→4T2 transition of Cr3+ ions, respectively. Those excitation spectrum peak positions show different degrees of blue shift with the increase in the Al3+ ions content. The blue shift of the first two peaks are due to the band gap energy of substrate and the electronegativity between Cr3+ ions and ligands increasing, respectively. The blue shift of the energy level transition of Cr3+ ion is attributed to crystal field strength increasing. The Cr3+ ion luminescence changes from a broadband emission to a narrowband emission with Al3+ doping, because the emission of Cr3+ ion changed from 4T2→4A2 to 2E→4A2 transition with the crystal field change after Al3+ ions doping. The Al3+ ions doping improved the long afterglow luminescence properties of samples, and the sample showed a longer visible near infrared when Al3+ ions content reaches 0.5. The thermoluminescence curve shows the sample with suitable trap energy level, and this is also the cause of the long afterglow luminescence materials..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 2921 (2013)
Near-Infrared Photoluminescence Properties of Natural Sodalite Activated with Mn and Fe Transition Metal Ions Doping
Tuerxun·Aidilibike, Bahetiguli·Asilibieke, and Aierken·Sidike
Na8Al6Si6O24Cl2∶Mn and Na8Al6Si6O24Cl2∶Fe NIR phosphors were prepared by a solid-solid reaction at high temperature. Their crystal structures of fluorescent powder were investigated by using X-ray powder diffraction (XRD), and their NIR emission spectrum and excitation spectrum were measured at room temperature. The maNa8Al6Si6O24Cl2∶Mn and Na8Al6Si6O24Cl2∶Fe NIR phosphors were prepared by a solid-solid reaction at high temperature. Their crystal structures of fluorescent powder were investigated by using X-ray powder diffraction (XRD), and their NIR emission spectrum and excitation spectrum were measured at room temperature. The main emission peak of Mn5+ in the Na8Al6Si6O24Cl2∶Mn phosphor was observed at 1 200 nm in the NIR spectral region under 400 or 602 nm excitation, attributing to the 3A2—3T2 and 3A2—1E transitions of Mn5+ ions. The characteristic NIR luminescence of Mn5+ in sodalite is greatly enhanced by co-doping manganese and sulfur. A mechanism of the energy transfer between S－2 and Mn5+ was also proposed here. The main emission peak of Fe2+ ions in the Na8Al6Si6O24Cl2∶Fe phosphor was recorded at 1 000 nm in the NIR region under the excitation of 334 or 500 nm. This photoluminescence originated from the 3T1—5E transition of Fe2+. Such an emission in the NIR region suggests a potential application in improving solar spectrum to enhance the efficiency of silicon solar cells..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 2926 (2013)
The Synthesis and Luminescence Measurement of YAG∶Ce3+ Phosphors by High Temperature Solid Phase Method
TONG Yi-ping, and CHEN Teng
YAG∶Ce3+ luminescence materials were prepared by a high-temperature solid state method. Different influencing factors, e.g., the doping amount of Ce3+, sintering temperature, and sintering time, were investigated by the orthogonal experiment method. The results showed that: (1) the influence of three factors on light-eYAG∶Ce3+ luminescence materials were prepared by a high-temperature solid state method. Different influencing factors, e.g., the doping amount of Ce3+, sintering temperature, and sintering time, were investigated by the orthogonal experiment method. The results showed that: (1) the influence of three factors on light-emitting intensity of YAG∶Ce3+ phosphors is in the following order, sintering temperature>>sintering time>the doping amount of Ce3+; (2) the optimum conditions for YAG∶Ce3+ phosphors are: sintering temperature 1 600 ℃, the doping amount of Ce3+ 0.10 mol, and sintering time 4 h. Under these conditions, the light-emitting intensity of YAG∶Ce3+ phosphors prepared is the largest. Furthermore, another optimum conditions are: sintering temperature 1 600 ℃, the doping amount of Ce3+ 0.08 mol, and sintering time 4 h, and the YAG∶Ce3+ phosphors prepared are also excellent based on them. The transition properties and spectral features of excitation and luminescence spectra of these synthesized phosphors were analyzed in detail and assigned as Ce3+ 4f—5d transition..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 2930 (2013)
Application of FTIR Spectrometry to Monitoring Chemosensitivity of Breast Cancer Cell Line Using 5-FU
HU Hai-jian, ZU Chao1, GUO Lin, HU Qing-nan, WANG Jian-sheng, XU Yi-zhuang, and WU Jin-guang
The purpose of the present study was to compare the changes of infrared spectrum of breast cancer cell line MCF-7 treated by 5-fluorouracil with various concentrations and treating time. The results indicate that the relative intensity ratios of I2 920/I1 460 increased in the FTIR spectra of cell line MCF-7 while I1 40The purpose of the present study was to compare the changes of infrared spectrum of breast cancer cell line MCF-7 treated by 5-fluorouracil with various concentrations and treating time. The results indicate that the relative intensity ratios of I2 920/I1 460 increased in the FTIR spectra of cell line MCF-7 while I1 400/I1 460, I1 080/I1 550 and I1 240/I1 550 decreased significantly within forty-eight hours, however, no regular change was observed during 48～72 hours. The relative intensity ratio of I1 640/I1 550 decreases along with the increase in the concentration of 5-fluorouracil. The changes of infrared spectra are consistent with the biochemical changes in breast cancer cell, and it can be the reference designators when assessing curative effect of breast cancer cell by FTIR spectrometry..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 2935 (2013)
Chemical Structure of Bioethanol Lignin by Low-Temperature Alkaline Catalytic Hydrothermal Treatment
LIU Xiao-huan, ZHANG Ming-ming, WANG Ji-fu, XU Yu-zhi, WANG Chun-peng, and CHU Fu-xiang
In order to improve the reaction activity of bioethanol lignin, we investigated the activation of bioethanol lignin by a hydrothermal treatment method. Catalytic hydrothermal treatment of bioethanol lignin was performed at 180 ℃ for 3 h in the presence of alkaline solutions (NaOH, Na2CO3, KOH and K2CO3), the change in In order to improve the reaction activity of bioethanol lignin, we investigated the activation of bioethanol lignin by a hydrothermal treatment method. Catalytic hydrothermal treatment of bioethanol lignin was performed at 180 ℃ for 3 h in the presence of alkaline solutions (NaOH, Na2CO3, KOH and K2CO3), the change in bioethanol lignin structures was studied comparatively by FTIR, 1H NMR, GPC and elemental analysis. FTIR spectra showed that after alkali hydrothermal treatment, the band at 1 375 cm-1 attributed to the phenolic hydroxyl groups increased, and the band intensity at 1 116 cm-1 attributed to the ether bond decreased. On the other hand, the band at 1 597 and 1 511 cm-1 attributed to aromatic skeletal vibration remained almost unchanged. 1H NMR spectra showed that after alkali hydrothermal treatment, the number of aromatic methoxyl is increased, and based on the increment of the content of phenolic hydroxyl, the catalytic activity can be ranked as follows: KOH>NaOH>K2CO3>Na2CO3. Especially for KOH, the increment of the content of phenolic hydroxyl was 170%, because the ion radius of potassium cation is bigger than sodium cation, so the potassium cations more easily formed cation adducts with lignin. GPC results showed that the molecular weight of alkali hydrothermal treatment lignin decreased and the molecular distribution got wider. Elemental analysis showed that hydrothermal treatment could break the interlinkage between lignin and protein, which can reduce the protein content and increase the purity of lignin, meanwhile, the content of O and H both decreased, while C fell, indicating that the bioethanol lignin had suffered a decarbonylation reaction. This is the most benefit of the lignin as a substitute for phenol..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 2940 (2013)
Study on Quality of Five Hybrid Corn Kernels by FTIR Spectroscopy
SHI You-ming, YAN Cui-qiong, SUN Yan-lin, LI Dong-yu, and LIU Gang
The aim of this work was to study the feasibility of evaluating quality of corn kernels using Fourier transform infrared(FTIR) spectroscopy. The spectra of five kinds of hybrid corn kernels were obtained by infrared spectrometer rapidly. The infrared spectrum between 1 776 and 952 cm-1 was composed of absorption bands The aim of this work was to study the feasibility of evaluating quality of corn kernels using Fourier transform infrared(FTIR) spectroscopy. The spectra of five kinds of hybrid corn kernels were obtained by infrared spectrometer rapidly. The infrared spectrum between 1 776 and 952 cm-1 was composed of absorption bands of protein, starch and lipid mainly. The absorption band of starch was strong, and the band of protein was weak. The characteristic bands of starch, protein and lipid were highly overlapped, and main information was concealed. Curve-fitting the spectrum between 1 776 and 952 cm-1, significant information was presented. The percentage of band area at 1 051 and 1 548 cm-1 in total band area has a linear relationship with the concentration of starch and protein. The results showed that Fourier transform infrared spectroscopy combined with curve-fitting could be used to analyse the concentration of starch and protein in corn kernel, and provides a rapid and convenient method to study hybrid corn..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 2945 (2013)
Research on the Online Detection of Oil Concentration in Water
ZHAO You-quan, YU Hai-bo, and HE Feng
A novel technology to measure oil concentration in water is presented, and mie-scattering theory was creatively introduced to oil-in-water detection in the present study. A variety of oil samples were examined to obtain both scattering and infrared absorption spectra, and the linear correlation between light scatteringA novel technology to measure oil concentration in water is presented, and mie-scattering theory was creatively introduced to oil-in-water detection in the present study. A variety of oil samples were examined to obtain both scattering and infrared absorption spectra, and the linear correlation between light scattering intensity and measures with infrared spectrophotometry is more than 0.98. In addition, compared to the conventional methods, light scattering method requires no chemical reagent, and it is suitable for in situ measurement of oil in water..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 2949 (2013)
Study on the Relationship between Structure and Spectroscopy of Two Compounds Containing 2,2′-Bipy and ［MoO3］ Cluster Skeletons
ZHANG Zi-ming, CHEN Yi-ping, YOU Zhu-chai, SU Liu-qin, WANG Hao, and SUN Yan-qiong
Two compounds of molybdate with 2,2′-bipy and ［MoO3］: ［(2,2′-bipy)2(MoO3)3］n(Ⅰ) and ［(2,2′-bipy)(MoO3)］n(Ⅱ) were successfully synthesized by hydrothermal synthesis method with programmable temperature control. In order to clarify the relationship between the structure and spectroscopy of these two compounds, both of thTwo compounds of molybdate with 2,2′-bipy and ［MoO3］: ［(2,2′-bipy)2(MoO3)3］n(Ⅰ) and ［(2,2′-bipy)(MoO3)］n(Ⅱ) were successfully synthesized by hydrothermal synthesis method with programmable temperature control. In order to clarify the relationship between the structure and spectroscopy of these two compounds, both of them were characterized by means of X-ray powder diffraction (XRD), Fourier transform infrared spectra(FTIR), thermal perturbation 2D-IR correlation spectrum (2D-IR COS), thermogravimetric analysis(TGA), scanning electron microscopy(SEM), High temperature infrared analysis, UV-Vis DRS adsorption spectra and solid fluorescence spectrum to investigate the relationship between structure and properties of the title compounds. The powder XRD patterns of the complexes are well matched with the simulation based on single-crystal analysis, which indicate that compound Ⅰ and Ⅱ are in a pure phase. The characteristics of vibration frequency of FTIR and thermal perturbation relative spectral response of 2D-IR peak is consistent with the compound Ⅰ and Ⅱ structure analysis. The synchronous and asynchronous correlation 2D-IR spectra of compounds also identified the compounds Ⅰ and Ⅱ molybdenum-oxygen cluster skeletons sequencing of vibration intensity change with temperature consistent with the high temperature infrared analysis. Through the TGA and high temperature infrared analysis it was found that the decomposition temperature was more than 300 ℃ and maximum weight losses rates above 800 ℃, which suggest that they have good thermal stability. According to the UV-Vis DRS spectrum of the compound Ⅰ and Ⅱ there exists a wide ultraviolet absorption band in a range of 225 to 350 nm. The compound Ⅰand Ⅱsteady-state fluorescence spectrum under the excitation of 277 and 295 nm respectively revealed compound Ⅰ and Ⅱ have the strongest emission peak at 460 and 480 nm respectively. This paper illustrates the coordination situation of these two compounds, and reveals the inherent law of valence electrons in molecule energy level transition. In the meantime it was verified that the weak interaction not only plays a role of stability in the frame of the structure of the complexes, but also plays an important role in heat resistance..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 2953 (2013)
Near Infrared Spectroscopy Study on Water Content in Turbine Oil
CHEN Bin, LIU Ge, and ZHANG Xian-ming
Near infrared (NIR) spectroscopy combined with successive projections algorithm (SPA) was investigated for determination of water content in turbine oil. Through the 57 samples of different water content in turbine oil scanned applying near infrared (NIR) spectroscopy, with the water content in the turbine oil of 0～0.1Near infrared (NIR) spectroscopy combined with successive projections algorithm (SPA) was investigated for determination of water content in turbine oil. Through the 57 samples of different water content in turbine oil scanned applying near infrared (NIR) spectroscopy, with the water content in the turbine oil of 0～0.156%, different pretreatment methods such as the original spectra, first derivative spectra and differential polynomial least squares fitting algorithm Savitzky-Golay (SG), and successive projections algorithm (SPA) were applied for the extraction of effective wavelengths, the correlation coefficient (R) and root mean square error (RMSE) were used as the model evaluation indices, accordingly water content in turbine oil was investigated. The results indicated that the original spectra with different water content in turbine oil were pretreated by the performance of first derivative +SG pretreatments, then the selected effective wavelengths were used as the inputs of least square support vector machine (LS-SVM). A total of 16 variables selected by SPA were employed to construct the model of SPA and least square support vector machine (SPA-LS-SVM). There is 9 as The correlation coefficient was 0.975 9 and the root of mean square error of validation set was 2.655 8×10-3 using the model, and it is feasible to determine the water content in oil using near infrared spectroscopy and SPA-LS-SVM, and an excellent prediction precision was obtained. This study supplied a new and alternative approach to the further application of near infrared spectroscopy in on-line monitoring of contamination such as water content in oil..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 2959 (2013)
Gemology and Spectra Characterization of Gem Garnet from Muling City, Heilongjiang Province
CHEN Tao, LIU Yun-gui, YIN Zuo-wei, and LIU Ni
Cenozoic basalts gem-garnets from Muling City, Heilongjiang Province were studied by using standard gemological methods, electron microprobe, Raman spectroscopy, infrared spectroscopy, and ultraviolet-visible spectroscopy to obtain the gemology and spectra characterization. Chemical composition analysis indicates that Cenozoic basalts gem-garnets from Muling City, Heilongjiang Province were studied by using standard gemological methods, electron microprobe, Raman spectroscopy, infrared spectroscopy, and ultraviolet-visible spectroscopy to obtain the gemology and spectra characterization. Chemical composition analysis indicates that the garnets are pyropes with some impurity element Fe, Ca, Mn, Cr, and Ti. The average chemical structure formula of the gem-garnet is (Mn0.022Ca0.455, Fe2+0.720, Mg1.793)∑=2.990(Ti0.003Cr0.009 Fe3+0.062 Al1.951)∑=2.025(SiO4)3. Roman spectrum analysis suggests that there are mixed-phases in the garnet, which can be shown by the Roman shift which is caused by bridging oxygen vibration of garnet. The Roman shifts of bridging oxygen bending vibration of pyrope are at 560 cm-1 (A1g), and 641 cm-1 (Eg+F2g), while the Roman shifts of bridging oxygen bending vibration caused by Eg+F2g of almandine and grossular are at 507 and 486 cm-1. IR functional group area indicates that the pyropes have no molecules water, but seldom pyropes have a little structure water, which forms three stepped weak absorption peaks at 3 585, 3 566 and 3 544 cm-1 respectively. Most pyropes are brown-red, which is caused by electronic transitions of impurity ions Cr3+, Fe3+ and Mn2+. UV-Vis spectra show that absorption peaks caused by electron transition of Fe3+ are at 570, 521 and 502 nm, while absorption peaks caused by electron transition of Mn2+ are at 460 and 430 nm, and absorption peaks caused by electron transition of Cr3+ are at 690 and 367 nm..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 2964 (2013)
A Coarse-to-Fine Registration Method for Satellite Infrared Image and Visual Image
HU Yong-li, WANG Liang, LIU Rong, ZHANG Li, and DUAN Fu-qing
In the present paper, in order to resolve the registration of the multi-mode satellite images with different signal properties and features, a two-phase coarse-to-fine registration method is presented and is applied to the registration of satellite infrared images and visual images. In the coarse registration phase of In the present paper, in order to resolve the registration of the multi-mode satellite images with different signal properties and features, a two-phase coarse-to-fine registration method is presented and is applied to the registration of satellite infrared images and visual images. In the coarse registration phase of this method, the edge of infrared and visual images is firstly detected. Then the Fourier-Mellin transform is adopted to process the edge images. Finally, the affine transformation parameters of the registration are computed rapidly by the transformation relation between the registering images in frequency domain. In the fine registration phase of the proposed method, the feature points of infrared and visual images are firstly detected by Harris operator. Then the matched feature points of infrared and visual images are determined by the cross-correlation similarity of their local neighborhoods. The fine registration is finally realized according to the spatial correspondent relation of the matched feature points in infrared and visual images. The proposed coarse-to-fine registration method derives both the advantages of two methods, the high efficiency of Fourier-Mellin transform based registration method and the accuracy of Harris operator based registration method, which is considered the novelty and merit of the proposed method. To evaluate the performance of the proposed registration method, the coarse-to-fine registration method is implemented on the infrared and visual images captured by the FY-2D meteorological satellite. The experimental results show that the presented registration method is robust and has acceptable registration accuracy..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 2968 (2013)
Study of Selecting Characteristic Wavelengths in Qualitative Analysis of Near Infrared Spectroscopy
YU Jing, WEN Ya-dong, WANG Luo-ping, QIAN Ying-ying, MA Xiang, WANG Yi, ZHAO Long-lian, and LI Jun-hui
The present article proposed a method of stepwise selecting characteristic wavelengths based on minimum sum of correlation coefficients (SMCC). The maximization of the ratio of inter-class Euclidean distance to the sum of inner-class Euclidean distances was used as evaluation basis in qualitative analysis of near infraThe present article proposed a method of stepwise selecting characteristic wavelengths based on minimum sum of correlation coefficients (SMCC). The maximization of the ratio of inter-class Euclidean distance to the sum of inner-class Euclidean distances was used as evaluation basis in qualitative analysis of near infrared spectroscopy. Seventeen kinds of grading tobacco leaf in 2012, provided by Hongta Group, were used as experimental samples to verify the effectiveness of this new method. CO1 was selected as the reference category and ten points were selected as characteristic wavelengths. The results indicated that the average value of inner-class Euclidean distance, calculated by characteristic wavelengths, was 1.69 times as large as that calculated by all wavelengths. The average value of inter-class Euclidean distance, calculated by characteristic wavelengths, was 3.70 times as large as that calculated by all wavelengths. The average value of the ratio of inter-class Euclidean distance to the sum of inner-class Euclidean distances, calculated by characteristic wavelength, was 2.21 times as large as that calculated by all wavelengths. The ratio of characteristic wavelengths was increased. The characteristic wavelengths can express the classical differences. It was showed that SMCC was an effective way to select characteristic wavelengths in qualitative analyses of near infrared spectroscopy..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 2973 (2013)
Study on the Occurrence Status of Formamide in Kaolinite-Formamide Intercalation System and the Microstructure of Its Compounds by FTIR and XRD
ZHANG Sheng-hui, ZHOU Ya-chong, OU Xue-mei, QIANG Ying-huai, and XIA Hua
The objectives of this study are to investigate the possible occurrence status of formamide in the intercalation system, the founction of water and the molecular configurations and orientations of formamide inserted into the interlayer of kaolinite, by washing the products with acetone to eliminate the interferences duThe objectives of this study are to investigate the possible occurrence status of formamide in the intercalation system, the founction of water and the molecular configurations and orientations of formamide inserted into the interlayer of kaolinite, by washing the products with acetone to eliminate the interferences due to the outersurface absorbed formamide molecules in FTIR spectrometry. The results show that the intercalated, absorbed and free formamide probably exist in the intercalation system. Free formamide is easily to be eliminated selectively by drying, whereas the absorbed formamide is removed only by washing with the proper eluting reagent. H2O also is inserted into the interlayer during the formamide molecules’ intercalation, which is deintercalated after the compounds being dried. Intercalation caused blue shifts of the inner surface OH stretching bands from 3 687 to 3 692 cm-1, and deforming bands from 911 to 906 cm-1 , the bands at 3 651 cm-1 disappeared with a new band appearing at 3 539 cm-1. The frequency of the Si—O bands of kaolinite was slightly shifted. These IR bands changes implied the breaking of the H-bonds between layers of kaolinite, and the formation of new H-bonds between the kaolinite and the inserting formamide molecules in the intercalation compounds. The formamide molecules intercalated were oriented with the C—N bond perpendicular or nearly perpendicular to the (001) surface of the kaolininte and formed 2 types of H-bonding with inner-surface hydroxyls and siloxane layer of the kaolinite respectively through NH2. A novel model was provided to analyse the microstructure of kaolinite-formamide intercalation compounds. The results show that computation data is in good agreement with experimental data..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 2978 (2013)
Current Status and Prospects of Portable NIR Spectrometer
YU Xin-yang, LU Qi-peng, GAO Hong-zhi, and PENG Zhong-qi
Near-infrared spectroscopy (NIRS) is a reliable, rapid, and non-destructive analytical method widely applied in as a number of fields such as agriculture, food, chemical and oil industry. In order to suit different applications, near-infrared spectrometers are now varied. Portable near-infrared spectrometers are neededNear-infrared spectroscopy (NIRS) is a reliable, rapid, and non-destructive analytical method widely applied in as a number of fields such as agriculture, food, chemical and oil industry. In order to suit different applications, near-infrared spectrometers are now varied. Portable near-infrared spectrometers are needed for rapid on-site identification and analysis. Instruments of this kind are rugged, compact and easy to be transported. In this paper, the current states of portable near-infrared spectrometers are reviewed. Portable near-infrared spectrometers are built of different monochromator systems: filter, grating, Fourier-transform methods, acousto-optic tunable filter (AOTF) and a large number of new methods based on micro-electro-mechanical systems (MEMS). The first part focuses on working principles of different monochromator systems. Advantages and disadvantages of different systems are also briefly mentioned. Descriptions of each method are given in turn. Typical spectrometers of each kind are introduced, and some parameters of these instruments are listed. In the next part we discuss sampling adapters, display, power supply and some other parts, which are designed to make the spectrometer more portable and easier to use. In the end, the current states of portable near-infrared spectrometers are summarized. Future trends of development of portable near-infrared spectrometers in China and abroad are discussed..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 2983 (2013)
Research on Early Diagnosis of Esophageal Cancer by Raman Spectroscopy of Human Hemoglobin
ZHOU Xue, CHEN Guang-yi, ZHANG Jian-min, FAN Chun-zhen, LIANG Er-jun, GUO Yan, and TANG Wei-yue
The Raman spectrums of hemoglobin from 20 normal persons and 21 esophageal cancer patients were measured and analyzed in the present paper, the results show obvious differences between the Raman spectrums of esophageal cancer patients and normal persons. Compared with normal persons, there are more iron ions in low spiThe Raman spectrums of hemoglobin from 20 normal persons and 21 esophageal cancer patients were measured and analyzed in the present paper, the results show obvious differences between the Raman spectrums of esophageal cancer patients and normal persons. Compared with normal persons, there are more iron ions in low spin state and less in high spin state in the hemoglobin of esophageal cancer patients. It indicates that some iron ions in high spin state turned to low spin state because of cancerization, and this experimental result coincides with the fact that hemolysis is more likely to occur in cancer patients. Principal component analysis(PCA) was employed to get a three-dimensional scatter plot of PC scores for the health and cancer groups, and it can be learned that they are distributed in separate areas. By using the method of discriminate analysis, it was found that the diagnostic algorithm separates the two groups with sensitivity of 90.5% and diagnostic specificity of 95%, and the overall diagnostic accuracy was 92.7%.The results from this exploratory study demonstrate that Raman spectroscopy combined with multivariate analysis would be an effective method for early diagnosis of esophageal cancer..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 2989 (2013)
Genesis Study of Omphacite at High Pressure and High Temperature
XIAO Ben-fu, YI Li, WANG Duo-jun, XIE Chao, TANG Xue-wu, LIU Lei, and CUI Yue-ju
The melting and recrystallizing experiments of alkali basalt powder and mixture of pure oxides mixed as stoichiometry were performed at 3 GPa and 1 200 ℃. Electronic microprobe analysis and Raman spectra showed that the recrystallized products were omphacites, the FWHM (full width at half maximum) of the Raman peak wasThe melting and recrystallizing experiments of alkali basalt powder and mixture of pure oxides mixed as stoichiometry were performed at 3 GPa and 1 200 ℃. Electronic microprobe analysis and Raman spectra showed that the recrystallized products were omphacites, the FWHM (full width at half maximum) of the Raman peak was narrow and its shape was sharp, which is attributed to the stable Si—O tetrahedral structure and the high degree of order in omphacite. Based on the results of previous studies, the influencing factors of omphacite genesis and its primary magma were discussed. The results showed that the formation of omphacite could be affected by many factors, such as the composition of parent rocks, the concentration of fluid in the system and the conditions of pressure and temperature. This result could support some experimental evidences on the genesis studies of omphacite and eclogite..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 2993 (2013)
Research on Prediction Method of Fatty Acid Content in Edible Oil Based on Raman Spectroscopy and Multi-Output Least Squares Support Vector Regression Machine
DENG Zhi-yin, ZHANG Bing, DONG Wei, and WANG Xiao-ping
For the purpose of the rapid prediction of saturated fatty acid, oleic acid, linoleic acid content in edible vegetable oil, the Raman spectra of a batch of edible vegetable oils and their one-one mixtures with different ratios were measured in the range of 800~2 000 cm-1, 91 samples were measured totally in this researFor the purpose of the rapid prediction of saturated fatty acid, oleic acid, linoleic acid content in edible vegetable oil, the Raman spectra of a batch of edible vegetable oils and their one-one mixtures with different ratios were measured in the range of 800~2 000 cm-1, 91 samples were measured totally in this research, the obtained Raman spectra data were preprocessed by a new method proposed in this paper called auto-set fulcrums baseline fitting method based on peak-seeking algorithm, and 8 characteristic peak values (872 cm-1［ν(C—C)］, 972 cm-1［δ(CC)trans］, 1 082 cm-1［ν(C—C)］, 1 267 cm-1［δ(C—H)cis］, 1 303 cm-1［δ(CH2)twisting］, 1 442 cm-1［δ(CH2) scissoring］, 1 658 cm-1［ν(CC)cis］, 1 748 cm-1［ν(CO)］) were extracted to be the eigenvalues for the whole spectra, among the 8 peaks there are three peaks(972, 1 267, 1 658 cm-1) that play an important role in the establishment of mathematical model, they are closely concerned with CC band which distinguishes the three fatty acid types. By using these eigenvalues as inputs, and actual saturated fatty acid, oleic acid, linoleic acid contents of sample oils as outputs, a prediction mathematical model that predicts simultaneously the three fatty acid contents was established using multiple regression analysis: multi-output least squares support vector regression machine(MLS-SVR) and partial least squares(PLS). Results show that the MLS-SVR has better effects. The predicting results are compared with results of gas chromatography(GC), and the obtained root mean square error of prediction(RMSEP) for saturated fatty acid, oleic acid, linoleic acid are 0.496 7%, 0.840 0% and 1.019 9%, and the correlation coefficients (r) are 0.813 3, 0.999 2 and 0.998 1, respectively. When this model is applied in the detection of new unknown oil samples, the prediction error does not exceed 5%. Results show that the Raman spectra analysis technology based on MLS-SVR can be a convenient, fast, non-destructive, and precise new method for oil detection..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 2997 (2013)
Application of Near Infrared Reflectance Spectroscopy to Predict Meat Chemical Compositions: A Review
TAO Lin-li, YANG Xiu-juan, DENG Jun-ming, and ZHANG Xi
In contrast to conventional methods for the determination of meat chemical composition, near infrared reflectance spectroscopy enables rapid, simple, secure and simultaneous assessment of numerous meat properties. The present review focuses on the use of near infrared reflectance spectroscopy to predict meat chemical cIn contrast to conventional methods for the determination of meat chemical composition, near infrared reflectance spectroscopy enables rapid, simple, secure and simultaneous assessment of numerous meat properties. The present review focuses on the use of near infrared reflectance spectroscopy to predict meat chemical compositions. The potential of near infrared reflectance spectroscopy to predict crude protein, intramuscular fat, fatty acid, moisture, ash, myoglobin and collagen of beef, pork, chicken and lamb is reviewed. This paper discusses existing questions and reasons in the current research. According to the published results, although published results vary considerably, they suggest that near-infrared reflectance spectroscopy shows a great potential to replace the expensive and time-consuming chemical analysis of meat composition. In particular, under commercial conditions where simultaneous measurements of different chemical components are required, near infrared reflectance spectroscopy is expected to be the method of choice. The majority of studies selected feature-related wavelengths using principal components regression, developed the calibration model using partial least squares and modified partial least squares, and estimated the prediction accuracy by means of cross-validation using the same sample set previously used for the calibration. Meat fatty acid composition predicted by near-infrared spectroscopy and non-destructive prediction and visualization of chemical composition in meat using near-infrared hyperspectral imaging and multivariate regression are the hot studying field now. On the other hand, near infrared reflectance spectroscopy shows great difference for predicting different attributes of meat quality which are closely related to the selection of calibration sample set, preprocessing of near-infrared spectroscopy and modeling approach. Sample preparation also has an important effect on the reliability of NIR prediction; in particular, lack of homogeneity of the meat samples influenced the accuracy of estimation of chemical components. In general the predicting results of intramuscular fat, fatty acid and moisture are best, the predicting results of crude protein and myoglobin are better, while the predicting results of ash and collagen are less accurate..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 3002 (2013)
Alfalfa Quality Evaluation in the Field by Near-Infrared Reflectance Spectroscopy
XU Rui-xuan, LI Dong-ning, YANG Dong-hai, LIN Jian-hai, XIANG Min, and ZHANG Ying-jun
To explore the feasibility of using near-infrared reflectance spectroscopy(NIRS) to evaluate alfalfa quality rapidly in the field and try to find the appropriate machine and sample preparation method, the representative population of 170 fresh alfalfa samples collected from different regions with different stages and dTo explore the feasibility of using near-infrared reflectance spectroscopy(NIRS) to evaluate alfalfa quality rapidly in the field and try to find the appropriate machine and sample preparation method, the representative population of 170 fresh alfalfa samples collected from different regions with different stages and different cuts were scanned by a portable NIRS spectrometer （1 100～1 800 nm）. This is the first time to build models of fresh alfalfa to rapidly estimate quality in the field for harvesting in time. The calibrations of dry matter(DM), crude protein(CP), neutral detergent fiber(NDF) and acid detergent fiber (ADF)were developed through the partial least squares regression(PLS). The determination coefficients of cross-validation (R2CV) were 0.831 4, 0.597 9, 0.803 6, 0.786 1 for DM, CP, NDF, ADF, respectively; the root mean standard error of cross-validation(RMSECV) were 1.241 1, 0.261 4, 0.990 3, 0.830 6; The determination coefficients of validation (R2V) were 0.815 0, 0.401 1, 0.784 9, 0.752 1 and the root mean standard errors of validation(RMSEP）were 1.06, 0.31, 0.95, 0.80 for DM, CP, NDF, ADF, respectively. For fresh alfalfa ,the calibration of DM, NDF, ADF can do rough quantitative analysis but the CP’s calibration is failed. however, as CP in alfalfa hay is enough for animal and the DM, NDF and ADF is the crucial indicator for evaluating havest time, the model of DM, NDF and ADF can be used for evaluating the alfalfa quality rapidly in the field..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 3010 (2013)
Application of SVR in Quantitative Analysis of Wines
LUO Tao, WEI Ji-ping, ZHAO Yu-ping, and ZHANG Jun
Fourier transform infrared spectroscopy has been widely used in some related fields, thus induces the rapid development of quantitative analysis method based on Lambert-Beer’s Law and chemometrics in recent years. The selection of appropriate pre-processing method and calibration model is extremely crucial to the quantFourier transform infrared spectroscopy has been widely used in some related fields, thus induces the rapid development of quantitative analysis method based on Lambert-Beer’s Law and chemometrics in recent years. The selection of appropriate pre-processing method and calibration model is extremely crucial to the quantitative analysis. The present paper selected 30 wine samples and used infrared spectroscopy combined with vector regression algorithm SVR quantitative analysis model with standard normal variate, baseline correction and outliers elimination to analyze four representative components of wine. Satisfactory results were gained while the relative errors were limited to less than 5%. This method can be applied to the wine representative quantitative analysis for the material content..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 3014 (2013)
Study on Nondestructive Rapid Identification Method of Foods Containing Trans-Fatty Acids Using Diffuse Near Infrared Spectroscopy
AN Xue-song, SONG Chun-feng, YUAN Hong-fu, XIE Jin-chun, and LI Xiao-yu
A rapid nondestructive method for identifying intact foods containing trans fatty acids (TFA) using diffuse near infrared spectroscopy (NIR) was proposed in the present paper. The diffuse Fourier transform near infrared (FT-NIR) spectra of intact samples were collected by fiber probe, and the reference data of TFA contA rapid nondestructive method for identifying intact foods containing trans fatty acids (TFA) using diffuse near infrared spectroscopy (NIR) was proposed in the present paper. The diffuse Fourier transform near infrared (FT-NIR) spectra of intact samples were collected by fiber probe, and the reference data of TFA content were determined by Chinese standard method GB/T 22110—2008 (gas chromatography (GC) method). In this work, all the samples were classified into two categories: foods with TFA and foods without TFA according to the TFA content of the foods. The identification models were established by different supervised pattern recognition algorithms including partial least square discriminant analysis (PLSDA), support vector machine (SVM), soft independent modeling of class analogy (SIMCA) and K-nearest neighbor method (KNN) etc. The performances of the established models employing different algorithms, data pretreatments and wavelength bands were compared. The results show that PLSDA and SVM algorithms have the ability of identifying intact foods with TFA, and the performance of identification models established by PLSDA is better than that of SVM. The PLSDA models established by the wavelength bands of 4 138～4 428, 5 507～5 963 and 7 794～8 960 cm-1 which were pretreated with pretreatment methods of auto scaling and second derivative have the best performance. The correct classification percentages of its calibration and validation set are 96.4% and 88%, respectively, which indicates that this method is feasible for the identification of foods with TFA. This NIR method above mentioned has the characteristics of rapidness, non-destruction and easy operation due to the elimination of sample pretreatment such as oil extraction and grinding, therefore it is very suitable for on-line and in-site detection application..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 3019 (2013)
Identification of Nanfeng Mandarin from Different Origins by Using Near Infrared Spectroscopy Coupled with Principal Components Analysis
WEI Yuan-long, YIN Chang-hai, CHEN Gui-ping, HUANG Jie, ZHANG Wei-bing, and DU Yi-ping
The identification of Nanfeng mandarins from different origins was developed by using near infrared spectroscopy (NIR) and principal components analysis (PCA). Mandarins from different places in one orchard, and from different orchards in three towns of Nanfeng county were studied. Also differences among Shaowu, LiucheThe identification of Nanfeng mandarins from different origins was developed by using near infrared spectroscopy (NIR) and principal components analysis (PCA). Mandarins from different places in one orchard, and from different orchards in three towns of Nanfeng county were studied. Also differences among Shaowu, Liucheng and Nanfeng were investigated. Furthermore, the effect of storage time of mandarins on the PCA model was considered. The results demonstrate that there was no clear diversity of the mandarins in one origin but great differences existed among different ones. And the storage time of mandarins played little role in the discrimination model. The method of multiple scattering correction (MSC) coupled with second derivative was selected to build PCA discrimination models compared with other data pretreatment methods. The proposed model would be a reference method for origin identification of Nanfeng mandarin..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 3024 (2013)
Nondestructive Recognization of Mountain Cultivated Ginseng and Garden Cultivated Ginseng by FTIR Microspectroscopy
BU Hai-bo, WANG Feng, LIN Hong-ying, GUO Zhi-yong, YUAN Shao-xiong, PAN Li-li, XU Xiao-jia, LI Xiang-ri, WANG Gang-li, and LIN Rui-chao
Fourier transform infrared (FTIR) microspectroscopy technology is the combination of the FTIR spectrometer and the microscope. This technology is of simple preparation of the samples, can be used in micro-area analysis and micro-samples, and reflect the nature of the samples spectra. Panax ginseng include mountain cultFourier transform infrared (FTIR) microspectroscopy technology is the combination of the FTIR spectrometer and the microscope. This technology is of simple preparation of the samples, can be used in micro-area analysis and micro-samples, and reflect the nature of the samples spectra. Panax ginseng include mountain cultivated ginseng (MCG), garden cultivated ginseng (GCG) and mountain wild ginseng (MWG), but the excavation of MWG is prohibited in China. So, only MCG and GCG were collected and recorded in Chinese pharmacopoeia. In this study, we developed a discriminant analysis (DA) method for recognition of MCG and GCG using FTIR microspectroscopy technology. Twenty MCG samples and twenty four GCG samples were obtained, and their spectra of IR microspectroscopy were collected. Then 33 samples were randomly selected into calibration set and the remaining 11 of the samples were selected into validation set. The authors optimized the pretreatment method, the principal components, the modeling region and the scanning parts when developing the models. The optimized model of discriminant analysis was developed using the pretreatment multiplicative scatter correction (MSC)+Savitzky-Golay filter (SG) smoothing, the region 3 932.14～669.18 cm-1, 4 principal components and the rhizome part. The accuracy of the optimized model got up to 100%. The result demonstrated that infrared microspectroscopy technology combined with DA is of simple operation, rapid, nondestructive and effective, and can be applied to recognize MCG and GCG..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 3028 (2013)
Identification of Adulterated Milk Based on Two-Dimensional Correlation Near-Infrared Spectra Parameterization and BP Neural Network
MIAO Jing, CAO Yu-zhen, YANG Ren-jie, LIU Rong, SUN Hui-li, and XU Ke-xin
Discriminant models of adulterated milk and pure milk were established using BP neural network combined with two-dimensional (2D) correlation near-infrared spectra parameterization. Forty pure milk samples, 40 adulterated milk samples with urea (1～20 g·L-1) and 40 adulterated milk samples with melamine (0.01～3 g&#Discriminant models of adulterated milk and pure milk were established using BP neural network combined with two-dimensional (2D) correlation near-infrared spectra parameterization. Forty pure milk samples, 40 adulterated milk samples with urea (1～20 g·L-1) and 40 adulterated milk samples with melamine (0.01～3 g·L-1) were prepared respectively. Based on the characteristics of 2D correlation near-infrared spectra of pure milk and adulterated milk, 5 apparent statistic parameters were calculated based on the parameterization theory. Using 5 characteristic parameters, discriminant models of urea adulterated milk, melamine adulterated milk and two types of adulterated milk were built by BP neural network. The prediction rate of unknown samples were 95%, 100% and 96.7%, respectively. The results show that this method can extract effectively feature information of adulterant, reduce the input dimensions of BP neural network, and better realize qualitative analysis of adulterant in milk..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 3032 (2013)
Identification of Rapeseed Varieties by Infrared Spectroscopy Combined with Spectral Retrieval
LIU Fei, YANG Chun-yan, and LIU Gang
The infrared spectra of 75 samples of 15 rapeseed varieties were obtained by means of Fourier transform infrared (FTIR) spectroscopy technique. The results show that the infrared spectra of the samples are very similar. By the spectral professional software Omnic8.0, two spectral databases were constructed. Lib01 incluThe infrared spectra of 75 samples of 15 rapeseed varieties were obtained by means of Fourier transform infrared (FTIR) spectroscopy technique. The results show that the infrared spectra of the samples are very similar. By the spectral professional software Omnic8.0, two spectral databases were constructed. Lib01 includes the average spectra of 9 samples from Yunnan, while Lib02 is constructed from the average spectra of all 15 varieties. The correlation search and the squared differential difference retrieval of the spectra of Yunnan samples were performed with the spectral database Lib01 in full spectrum range, respectively. The obtained matching values reflect that the samples have the closest correlation with each other only within the same species, with the correct rate of 77.8% for the correlation search, and that of 82.2% for the latter. The squared differential difference retrieval for the 15 sample spectra was carried out with Lib02 in full spectral range and in the specified range of 1 700～950 cm-1, yielding correct rate of 82.7% and 90.6% respectively. These results show that FTIR combined with the spectral retrieval method can identify the different varieties of rapeseed, and the squared differential difference retrieval in the specified spectral range is a more effective and simple way for distinguishing different varieties of rapeseed..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 3036 (2013)
FTIR Spectrum and Detoxication of Extracellular Polymeric Substances Secreted by Microorganism
ZHANG Hai-ou, ZHOU Wei-zhi, MA Yu-hong, ZHAO Hai-xia, and ZHANG Yu-zhong
In order to explore the effect of extracelluar polymeric substances (EPS) on resistance and removal of heavy metals, the production of EPS, secreted by cadmium-resistant strain (SCSE425-7) and cadmium-removal strain (SCSE709-6) was investigated combined with Fourier transform infrared spectroscopy (FTIR). The results sIn order to explore the effect of extracelluar polymeric substances (EPS) on resistance and removal of heavy metals, the production of EPS, secreted by cadmium-resistant strain (SCSE425-7) and cadmium-removal strain (SCSE709-6) was investigated combined with Fourier transform infrared spectroscopy (FTIR). The results showed that the high resistance to cadmium of strain SCSE425-7 was related to the high production of soluble EPS, whereas SCSE709-6 secreted more insoluble EPS resulting in better cadmium removal performance. It was indicated that soluble extracellular carbohydrates may help the bacteria to enhance resistance to Cd2+, and insoluble EPS could contribute to Cd2+ removal effectively. The FTIR spectra showed that the peaks of amide and carboxyl were main functional groups for Cd2+ adsorption..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 3041 (2013)
Research on Application of Fluorescence Spectrum Imaging Method in Banlangen Granule Quality Evaluation
HE Qing, LIANG Lan, CHEN Zhen-qiang, PANG Qi-chang, ZHAO Jing, and MA Ji
The curative effect of Banlangen granule is directly affected by its quality, so it is very important to choose a kind of effective method for testing it. The chemical treatment is needed as a pre-treatment for the quality testing by using common method at present, which will change or destroy the sample. For dealing wThe curative effect of Banlangen granule is directly affected by its quality, so it is very important to choose a kind of effective method for testing it. The chemical treatment is needed as a pre-treatment for the quality testing by using common method at present, which will change or destroy the sample. For dealing with this problem, in the present paper, a fluorescence spectrum imaging experimental system based on LCTF (liquid crystal tunable filter) is set up to detect the characteristics fluorescence spectrum of Banlangen granules. The characteristic fluorescence spectrum curve of Banlangen standard material provided by Chinese Food Drugs Examination Research Institute is used as a reference substance for a comparison with other Banlangen granules. By normalizing the corresponding characteristic fluorescence spectrum of Banlangen granules of different raw materials, different manufacturers and different batches, the relationship between the characteristic fluorescence spectrum curve and the quality of Banlangen granule is discussed by using the method of comparative and cluster analysis. The experimental results show that the qualities of Banlangen granules are quite different from different manufacturers, which are basically reflected by the change in the intensity of fluorescence and peak position. All of these indicate that fluorescence spectrum imaging technology is a simple, rapid and nondestructive detection method for the quality control of Banlangen granule..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 3044 (2013)
Rapid Determination of Tetracycline Content in Duck Meat Using Particle Swarm Optimization Algorithm and Synchronous Fluorescence Spectrum
ZHAO Jin-hui, YUAN Hai-chao, LIU Mu-hua, XIAO Hai-bin, HONG Qian, and XU Jiang
Tetracycline under the condition of NaOH could be degraded to iso tetracycline which has strong fluorescent characteristic, and the prediction model of tetracycline contents in duck meat was developed with the combination of synchronous fluorescence spectrum, wavelet de-noising, particle swarm optimization algorithm (PTetracycline under the condition of NaOH could be degraded to iso tetracycline which has strong fluorescent characteristic, and the prediction model of tetracycline contents in duck meat was developed with the combination of synchronous fluorescence spectrum, wavelet de-noising, particle swarm optimization algorithm (PSO) and support vector regression (SVR), and it could realize the rapid prediction of tetracycline contents in duck meat and improve the accuracy of prediction model. In the process, 70 nm was selected as the optimum wavelength difference for the determination of tetracycline contents in duck meat by using parallel factor analysis (PARAFAC). Secondly, the db6 wavelet with 2 levels decomposition was used to reduce the noise of synchronous fluorescence spectrum, and the spectrum after wavelet de-noising was normalized, and 6 characteristic wavelengths were selected by using PSO. Lastly, the SVR model parameters (c, g) were optimized by using PSO. Furthermore, the performances of the models of PSO-SVR, PLS and PCR under the spectral condition of characteristic wavelengths selected by using PSO, and PSO-SVR under the spectral condition of full spectrum were compared. The experimental results showed that the predictive ability of the model of PSO-SVR under the spectral condition of characteristic wavelengths selected by using PSO was strongest, and the correlation coefficient and the root mean squared error of prediction were 0.952 0 and 17.6 mg·kg-1, respectively. This work proved that PSO could extract effectively the characteristic wavelengths of tetracycline in duck meat, and the model of PSO-SVR could satisfy the request of rapid determination of tetracycline contents in duck meat..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 3050 (2013)
The Detection of Flavonoids Glycosides from Ginkgo Biloba Based on Spectrofluorimetry
SHAO Ju-fang, WEN Zong-zhuang, and ZHU Hong-wei
Flavonoids glycosides from ginkgo are widely applied in pharmaceutical, food, daily necessities and other areas due to their variety of biological activities. To overcome the shortcoming of current methods of time wasting, complex operation and expensive costs, an accuracy, low costs and fast determination method was eFlavonoids glycosides from ginkgo are widely applied in pharmaceutical, food, daily necessities and other areas due to their variety of biological activities. To overcome the shortcoming of current methods of time wasting, complex operation and expensive costs, an accuracy, low costs and fast determination method was established for flavonoids glycosides from ginkgo. According to the principle that flavonoids can form fluorescent chelate with Al3+, the detection condition was explored with rutin as standard. The results showed that the fluorimetric intensy of chelate of rutin with Al3+ would be stabilized and achieve maximum with λex=400 nm and λem=520 nm, in Al(NO3)3-(HAc-NaAc) reaction system for 1 500 s with pH 3.6. The linear regression equation y=29.92x+36.49 (R2=0.986) was deduced with the concentration of rutin and fluorescence intensy, and the linear range 1.8×10－6～3.2×10－5 mol·L-1. Flavonoids glycosides of cell suspension cultures from ginkgo biloba was detected by this method. The recovery experiments were also carried out with the average recovery rate of 101.3%. The advantages of high sensitivity, reproducibility, simple operation, and low costs were showed, indicating its good prospects..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 3055 (2013)
Study on Microarea Characteristics of Calcite in Archaean BIF from Wuyang Area in South Margin of North China Craton and Its Geological Significances
LI Hong-zhong, ZHAI Ming-guo, ZHANG Lian-chang, YANG Zhi-jun, ZHOU Yong-zhang, WANG Chang-le, LIANG Jin, and LUO An
The results of Raman, SEM, CL and EDS analysis show that the quartz-type BIF (banded iron formation) in Tieshanmiao formation, from Wuyang area of south North China Craton mainly contains quartz, magnetite and a small quantity of calcite. In comparison, magnetites represent the highest automorphic degree, while calciteThe results of Raman, SEM, CL and EDS analysis show that the quartz-type BIF (banded iron formation) in Tieshanmiao formation, from Wuyang area of south North China Craton mainly contains quartz, magnetite and a small quantity of calcite. In comparison, magnetites represent the highest automorphic degree, while calcites contribute to the lowest automorphic degree. In addition, the automorphic degree of the quartz lies between magnetite and calcite. In the results of Raman analysis, the crystallinity and order degree are quite diverse in the vertical direction of the calcite band-like, and this is different from the calcite vein precipitating from the upper hydrothermal fluid. There are obvious plastic flow happening to calcite particles. During the process of plastic flow, the calcites are finally filled in the space between quartz and magnetite. This is the reason why the cross sectional shape and distributional characteristics of calcite aggregate are controlled by the particles of quartz and magnetite, which is also evidenced by the calcite filled into the slight interspace between two particles of quartz. In the Raman analysis, there are apparent differences of microarea component in calcite band-like, and this denotes that it is produced by the plastic flow and concourse process. What’s more, the calcite acts as the migration intermedium of tiny magnetite during their concourse and crystallization processes, which is witnessed by the concentrated particles of magnetite in small size in local parts of the calcites. With the help of calcite, the small magnetite particles join together to crystallize with bigger size or form aggregate of minerals..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 3061 (2013)
Influence of Human Body Target’s Spectral Characteristics on Visual Range of Low Light Level Image Intensifiers
ZHANG Jun-ju, YANG Wen-bin, XU Hui, LIU Lei, and TAO Yuan-yaun
To study the effect of different human target’s spectral reflective characteristic on low light level(LLL) image intensifier’s distance, based on the spectral characteristics of the night-sky radiation and the spectral reflective coefficients of common clothes, we established a equation of human body target’s spectral To study the effect of different human target’s spectral reflective characteristic on low light level(LLL) image intensifier’s distance, based on the spectral characteristics of the night-sky radiation and the spectral reflective coefficients of common clothes, we established a equation of human body target’s spectral reflective distribution, and analyzed the spectral reflective characteristics of different human targets wearing the clothes of different color and different material, and from the actual detection equation of LLL image intensifier distance, discussed the detection capability of LLL image intensifier for different human target. The study shows that the effect of different human target’s spectral reflective characteristic on LLL image intensifier distance is mainly reflected in the average reflectivity and the initial contrast of the target and the background C0. Reflective coefficient and spectral reflection intensity of cotton clothes are higher than polyester clothes, and detection capability of LLL image intensifier is stronger for the human target wearing cotton clothes. Experimental results show that the LLL image intensifiers have longer visual ranges for targets who wear cotton clothes than targets who wear same color but polyester clothes, and have longer visual ranges for targets who wear light-colored clothes than targets who wear dark-colored clothes. And in the full moon illumination conditions, LLL image intensifiers are more sensitive to the clothes’ material..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 3066 (2013)
Research on Developping the Spectral Dataset for Dunhuang Typical Colors Based on Color Constancy
LIU Qiang, WAN Xiao-xia, LIU Zhen, LI Chan, and LIANG Jin-xing
The present paper aims at developping a method to reasonably set up the typical spectral color dataset for different kinds of Chinese cultural heritage in color rendering process. The world famous wall paintings dating from more than 1700 years ago in Dunhuang Mogao Grottoes was taken as typical case in this research. The present paper aims at developping a method to reasonably set up the typical spectral color dataset for different kinds of Chinese cultural heritage in color rendering process. The world famous wall paintings dating from more than 1700 years ago in Dunhuang Mogao Grottoes was taken as typical case in this research. In order to maintain the color constancy during the color rendering workflow of Dunhuang culture relics, a chromatic adaptation based method for developping the spectral dataset of typical colors for those wall paintings was proposed from the view point of human vision perception ability. Under the help and guidance of researchers in the art-research institution and protection-research institution of Dunhuang Academy and according to the existing research achievement of Dunhuang Research in the past years, 48 typical known Dunhuang pigments were chosen and 240 representative color samples were made with reflective spectral ranging from 360 to 750 nm was acquired by a spectrometer. In order to find the typical colors of the above mentioned color samples, the original dataset was devided into several subgroups by clustering analysis. The grouping number, together with the most typical samples for each subgroup which made up the firstly built typical color dataset, was determined by wilcoxon signed rank test according to the color inconstancy index comprehensively calculated under 6 typical illuminating conditions. Considering the completeness of gamut of Dunhuang wall paintings, 8 complementary colors was determined and finally the typical spectral color dataset was built up which contains 100 representative spectral colors. The analytical calculating results show that the median color inconstancy index of the built dataset in 99% confidence level by wilcoxon signed rank test was 3.28 and the 100 colors are distributing in the whole gamut uniformly, which ensures that this dataset can provide reasonable reference for choosing the color with highest color constancy during the color rendering process of Dunhuang cultural heritage..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 3071 (2013)
Application of Bionic Technology to Speciation Analysis and Bioavailability Assessment of Nickel in Transgenic Soybean
CHEN Li-hui, LI Shun-xing, MOU Yang, ZHENG Feng-ying, LI Yan-cai, WANG Hui, ZHENG Na-yan, and XIE He-fang
The safety of transgenic food has been paid the most attention to by the public and scientists. Trace metal bioavailability could provide information for safety assessment of transgenic food. The critical functional digestion and absorption in the gastrointestinal tract were simulated by bionic gastrointestinal digestiThe safety of transgenic food has been paid the most attention to by the public and scientists. Trace metal bioavailability could provide information for safety assessment of transgenic food. The critical functional digestion and absorption in the gastrointestinal tract were simulated by bionic gastrointestinal digestion, metabolism of gut microbiota, and bionic biomembrane adsorption with liposome and then used for the pretreatment of transgenic and general soybeans. Ni speciation in the chyme was defined as affinity-liposome and water soluble Ni. Nickel bioavailability was assessed by the content of affinity-liposome Ni. .Water soluble Ni was the main species of nickel complex in the chyme. Nickel bioavailability was 4.1% for transgenic soybean and 3.3% for general soybean, which could be enhanced by gastrointestinal digestion and metabolism of gut microbiota. After transgene, nickel bioavailability was increased 24% but the content of affinity-liposome Ni was 122.3 ng·g-1 for transgenic soybean, just as 36% as that of general soybean..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 3075 (2013)
The Turbidity and pH Impact Analysis of Low Concentration Water Chemical Oxygen Demand Ultraviolet Absorption Detection
WU Guo-qing, BI Wei-hong, FU Guang-wei, LI Jian-guo, and JI Hong-yue
Configuration standard solution in the concentration range of 1~25 mg·L-1 of potassium hydrogen phthalate was usded as experimental subject, Ultraviolet absorption spectra was collected, the COD quantitative analysis model was established by partial least squares with different pretreatment methods and the turbidiConfiguration standard solution in the concentration range of 1~25 mg·L-1 of potassium hydrogen phthalate was usded as experimental subject, Ultraviolet absorption spectra was collected, the COD quantitative analysis model was established by partial least squares with different pretreatment methods and the turbidity of the compensation effect analysis was given. The results show the model uses smoothing first derivative pretreatment method, internal cross validation RMSECV root mean square value of 0.122 27, principal component number 4, the square of the prediction model correlation coefficient is 0.999 8, and the relative prediction error is in the range of 0.03%~1.7%; for 0~100 NTU’s turbidity solution, the relative standard deviation RSD is 2.3% after compensation; with pH in the range of 3~10, influence can be ignored..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 3079 (2013)
Grey Analysis of NIR Spectra and Prediction of Nitrogen Content in Jujube Leaves
YANG Wei, SUN Hong, ZHENG Li-hua, ZHANG Yao, and LI Min-zan
Jujube was chosen as the object in the present research. Spectra data of jujube leaves were collected during the period of budding, branch leaf, flowering and coloring. The nitrogen contents of jujube leaf samples were determined by Kjeldahl analysis method. Grey relation analysis between spectral reflectance and nitroJujube was chosen as the object in the present research. Spectra data of jujube leaves were collected during the period of budding, branch leaf, flowering and coloring. The nitrogen contents of jujube leaf samples were determined by Kjeldahl analysis method. Grey relation analysis between spectral reflectance and nitrogen content of jujube leaves was done based on Grey theory. It was found that the gray relation between spectral reflectance and nitrogen content of jujube leaves at 560, 678 and 786 nm was high. Nine kinds of vegetation index based on spectra data of NIR786, R678 and G570 were calculated. The gray relation of nine kinds of vegetation index was NDVI>GRVI>NDGI>GNDVI>CNDVI>RVI>GDVI>DVI>SAVI. NDVI, GRVI, NDGI, GNDVI and CNDVI were chosen to build prediction models of nitrogen content of jujube leaves. Spectra data of 560, 678 and 786 nm were also used to build prediction models of nitrogen content of jujube leaves. LS-SVM and GM(1, N) were used to build prediction module. The prediction R2 and verification R2 of LS-SVM module were 0.805 and 0.704 respectively when five kinds of vegetation index were used as input of prediction module. When when Spectra data of 560, 678 and 786 nm were used as input, the prediction R2 and verification R2 of LS-SVM prediction model were 0.772 and 0.685 respectively. The prediction R2 and verification R2 of GM(1, N) module were 0.927 7 and 0.895 8 respectively when spectra data of 560, 678 and 786 nm were used as input. The results of prediction GM(1, N) module which used five kinds of vegetation index as input were 0.547 6 and 0.489 7. From those results it was observed that grey theory only needed little information to build prediction module with high precision, so that it could be used in precision management of jujube plants..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 3083 (2013)
Spectral Properties of Light Migration in Apple Fruit Tissue
SUN Teng-fei, ZHANG Teng-teng, ZHENG Tian-tian, CAO Zeng-hui, and ZHANG Jun
The present paper simulates laser wavelength 632 and 750 nm Gaussian beam migration in apple fruit tissue using Monte-Carlo method, and researches the spectral properties of absorption and scattering. It was shown that the special energy distribution characteristics of Gaussian beam influenced the diffusion of the laseThe present paper simulates laser wavelength 632 and 750 nm Gaussian beam migration in apple fruit tissue using Monte-Carlo method, and researches the spectral properties of absorption and scattering. It was shown that the special energy distribution characteristics of Gaussian beam influenced the diffusion of the laser in the tissue, the reflection, absorption and transmittance of 750 nm by tissue are lower, there are more photons interacting with tissue within the tissue, and they can more clearly reflect the information within the tissue. So, the transmission characteristics of the infrared light were relatively strong in biology tissue, which was convenient for researching biology tissue..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 3088 (2013)
Active Crop Canopy Sensor-Based Nitrogen Diagnosis for Potato
YU Jing, LI Fei, QIN Yong-lin, and FAN Ming-shou
In the present study, two potato experiments involving different N rates in 2011 were conducted in Wuchuan County and Linxi County, Inner Mongolia. Normalized difference vegetation index (NDVI) was collected by an active GreenSeeker crop canopy sensor to estimate N status of potato. The results show that the NDVI readiIn the present study, two potato experiments involving different N rates in 2011 were conducted in Wuchuan County and Linxi County, Inner Mongolia. Normalized difference vegetation index (NDVI) was collected by an active GreenSeeker crop canopy sensor to estimate N status of potato. The results show that the NDVI readings were poorly correlated with N nutrient indicators of potato at vegetative Growth stage due to the influence of soil background. With the advance of growth stages, NDVI values were exponentially related to plant N uptake（R2=0.665） before tuber bulking stage and were linearly related to plant N concentration（R2=0.699） when plant fully covered soil. In conclusion, GreenSeeker active crop sensor is a promising tool to estimate N status for potato plants. The findings from this study may be useful for developing N recommendation method based on active crop canopy sensor..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 3092 (2013)
Measure of Sunscreen Cream Transmittance in UV Wave Range and Analysis of Sun Protection Effect
CAO Xiao-hua, and XIAO Duo
SPF and PA index present the resistance ability of sunscreen to UVA (Ultraviolet A) and UVB (Ultraviolet B) respectively. The present article focuses on the research on the relationship between ultraviolet transmittance and sunscreen ability based on definition of sunscreen efficiency and a simple and significant resulSPF and PA index present the resistance ability of sunscreen to UVA (Ultraviolet A) and UVB (Ultraviolet B) respectively. The present article focuses on the research on the relationship between ultraviolet transmittance and sunscreen ability based on definition of sunscreen efficiency and a simple and significant result was obtained by deducing. The technique we applied is spectral analysis dealing with ethanol-ethyl ether mixed solvent by ultraviolet and visible light spectrophotometer. We measured the UVA and UVB transmittance of 69 common sunscreen samples. The measurement result shows that spectral analysis method could differentiate sunscreens with different SPF and PA and identify whether the parameter value marked is accurate. So, an effective method is provided for the measurement of SPF and PA value. If different types of ultraviolet absorbent or UV scattering dose is added in sunscreen, the authors can distinguish them easily through the shape of the transmittance curve. In our sunscreen samples measured, domestic brands and imported brands are classified into two categories. By comparing the experimental results, the authors found that the domestic sunscreen and import sunscreen have no significant difference in sun block efficiency as long as the authors adopt the product of qualified manufacturer..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 3098 (2013)
Remote Sensing of Chlorophyll Fluorescence at Airborne Level Based on Unmanned Airship Platform and Hyperspectral Sensor
YANG Pei-qi, LIU Zhi-gang, NI Zhuo-ya, WANG Ran, and WANG Qing-shan
The solar-induced chlorophyll fluorescence (ChlF) has a close relationship with photosynthetic and is considered as a probe of plant photosynthetic activity. In this study, an airborne fluorescence detecting system was constructed by using a hyperspectral imager on board an unmanned airship. Both Fraunhofer Line DiscriThe solar-induced chlorophyll fluorescence (ChlF) has a close relationship with photosynthetic and is considered as a probe of plant photosynthetic activity. In this study, an airborne fluorescence detecting system was constructed by using a hyperspectral imager on board an unmanned airship. Both Fraunhofer Line Discriminator (FLD) and 3FLD used to extract ChlF require the incident solar irradiance, which is always difficult to receive at airborne level. Alternative FLD (aFLD) can overcome the problem by selecting non-fluorescent emitter in the image. However, aFLD is based on the assumption that reflectance is identical around the Fraunhofer line, which is not realistic. A new method, a3FLD, is proposed, which assumes that reflectance varies linearly with the wavelength around Fraunhofer line. The result of simulated data shows that ChlF retrieval error of a3FLD is significantly lower than that of aFLD when vegetation reflectance varies near the Fraunhofer line. The results of hyperspectral remote sensing data with the airborne fluorescence detecting system show that the relative values of retrieved ChlF of 5 kinds of plants extracted by both aFLD and a3FLD are consistent with vegetation growth stage and the ground-level ChlF. The ChlF values of aFLD are about 15% greater than a3FLD. In addition, using aFLD, some non-fluorescent objects have considerable ChlF value, while a3FLD can effectively overcome the problem..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 3101 (2013)
Comparison and Analysis of Hyperspectral Remote Sensing Identifiable Models for Different Vegetation under Waterlogging Stress
JIANG Jin-bao, Michael D Steven, HE Ru-yan, and CAI Qing-kong
With the global climate warming, flooding disasters frequently occurred and its influence scope constantly increased in China. The objective of the present paper was to study the leaf spectral features of vegetation (maize and beetroot) under waterlogging stress and design a hyperspectral remote sensing model to monitoWith the global climate warming, flooding disasters frequently occurred and its influence scope constantly increased in China. The objective of the present paper was to study the leaf spectral features of vegetation (maize and beetroot) under waterlogging stress and design a hyperspectral remote sensing model to monitor the flooding disasters through a field simulated experiment. The experiment was carried out in the Sutton Bonington Campus of University of Nottingham(52.8°N, 1.2°W) from May to August in 2008, and samples were collected one time every week and spectra were measured in the laboratory. The result showed that the reflectance of the maize and beetroot decreased in the 550 and 800～1 300 nm region, and the reflectance slightly increased in the 680 nm region. This paper chose NDVI, SIPI, PRI, SRPI, GNDVI and R800*R550/R680 to identify the vegetation under waterlogging stress, respectively. The result suggested that the SIPI and R800*R550/R680 was sensitive for maize under waterlogging stress, and then SIPI and PRI and R800*R550/R680 was sensitive for beetroot under waterlogging stress. In order to seek the best identifiable model, the normalized distances between means of control and stressed vegetation indices were calculated and analyzed, the result indicated that the distance of R800*R550/R680 is more than that of indices’ in the early stress stage, illustrated that the index identifiable ability for waterlogging stress is better than other indices, then the index has the strong sensitivity and stability. Therefore, the index R800*R550/R680 could be used to quickly extract flooding disaster area by using hyperspectral remote sensing, and would provide information support for disaster relief decisions..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 3106 (2013)
Spectral Inversion Models for Prediction of Red Soil Total Nitrogen Content in Subtropical Region (Fuzhou)
WU Ming-zhu, LI Xiao-mei, and SHA Jin-ming
The present paper studied the hyperspectral response characteristics of red soil, with 135 soil samples in Fuzhou city. After monitoring the hypersectral reflection of soil samples with ASD (analytical spectral device) and total nitrogen contents with Vario MAX(for nitrogen and carbon analysis), the paper gained the spThe present paper studied the hyperspectral response characteristics of red soil, with 135 soil samples in Fuzhou city. After monitoring the hypersectral reflection of soil samples with ASD (analytical spectral device) and total nitrogen contents with Vario MAX(for nitrogen and carbon analysis), the paper gained the spectral reflection data between 350～2 500 nm (resolution is 1 nm) and soil total nitrogen contents. Then the paper treated the hyperspectral reflection data with 5 mathematic conversions such as first derivative and second derivative conversions of original reflection, reciprocal logarithmic conversion and its first derivative and second derivative conversion in advance. The next step was to calculate the correlation coefficient of soil nitrogen and the above spectral information, and select the sensitive spectral bands according to the highest correlation coefficient. Finally, by designing different proportions of modeling and validation sample data sets, the paper established the quantitative linear models between soil total nitrogen contents and hyperspectral reflection and its 5 converted information, the final optimal mathematic model between soil nitrogen and hyperspectral information was significantly determined. Results showed that 634～688, 872, 873, 1 414 and 1 415 nm were the main sensitive bands for soil total nitrogen, and Y=5.384X664-1.039 (Y represents soil nitrogen content, X664 is the soil spectral absorbance value at 664 nm) was the optimal soil total nitrogen predicting model (in the model, the determination coefficients R2 and the RMSE of total nitrogen were 0.616 and 0.422 mg·g-1, the inspection coefficient R2 and the RMSE were 0.608 and 0.546 mg·g-1 respectively). The model can be used to rapidly monitor soil total nitrogen with hyperspectral reflection in Fuzhou area..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 3111 (2013)
Study of Automatic Marine Oil Spills Detection Using Imaging Spectroscopy
LIU De-lian, HAN Liang, and ZHANG Jian-qi
To reduce artificial auxiliary works in oil spills detection process, an automatic oil spill detection method based on adaptive matched filter is presented. Firstly, the characteristics of reflectance spectral signature of C—H bond in oil spill are analyzed. And an oil spill spectral signature extraction model is desigTo reduce artificial auxiliary works in oil spills detection process, an automatic oil spill detection method based on adaptive matched filter is presented. Firstly, the characteristics of reflectance spectral signature of C—H bond in oil spill are analyzed. And an oil spill spectral signature extraction model is designed by using the spectral feature of C—H bond. It is then used to obtain the reference spectral signature for the following oil spill detection step. Secondly, the characteristics of reflectance spectral signature of sea water, clouds, and oil spill are compared. The bands which have large difference in reflectance spectral signatures of the sea water, clouds, and oil spill are selected. By using these bands, the sea water pixels are segmented. And the background parameters are then calculated. Finally, the classical adaptive matched filter from target detection algorithms is improved and introduced for oil spill detection. The proposed method is applied to the real airborne visible infrared imaging spectrometer (AVIRIS) hyperspectral image captured during the deepwater horizon oil spill in the Gulf of Mexico for oil spill detection. The results show that the proposed method has, high efficiency, does not need artificial auxiliary work, and can be used for automatic detection of marine oil spill..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 3116 (2013)
Analysis of Cr in Soil by LIBS Based on Conical Spatial Confinement of Plasma
LIN Yong-zeng, YAO Ming-yin, CHEN Tian-bing, LI Wen-bing, ZHENG Mei-lan, XU Xue-hong, TU Jian-ping, and LIU Mu-hua
The present study is to improve the sensitivity of detection and reduce the limit of detection in detecting heavy metal of soil by laser induced breakdown spectroscopy(LIBS).The Cr element of national standard soil was regarded as the research object. In the experiment, a conical cavity with small diameter end of 20 mmThe present study is to improve the sensitivity of detection and reduce the limit of detection in detecting heavy metal of soil by laser induced breakdown spectroscopy(LIBS).The Cr element of national standard soil was regarded as the research object. In the experiment, a conical cavity with small diameter end of 20 mm and large diameter end of 45 mm respectively was installed below the focusing lens near the experiment sample to mainly confine the signal transmitted by plasma and to some extent to confine the plasma itself in the LIBS setup. In detecting CrⅠ425.44 nm, the beast delay time gained from experiment is 1.3 μs, and the relative standard deviation is below 10%. Compared with the setup of non-spatial confinement, the spectral intensity of Cr in the soil sample was enhanced more than 7%. Calibration curve was established in the Cr concentration range from 60 to 400 μg·g-1. Under the condition of spatial confinement, the liner regression coefficient and the limit of detection were 0.997 71 and 18.85 μg·g-1 respectively, however, the regression coefficient and the limit of detection were 0.991 22 and 36.99 μg·g-1 without spatial confinement. So, this shows that conical spatial confinement can improve the sensitivity of detection and enhance the spectral intensity. And it is a good auxiliary function in detecting Cr in the soil by laser induced breakdown spectroscopy..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 3120 (2013)
Determination of High Content of Tin in Geochemical Samples by Solid Emission Spectrometry
YAO Jian-zhen, HAO Zhi-hong, TANG Rui-ling, LI Xiao-jing, LI Wen-ge, and ZHANG Qin
A method for the determination of high content of tin in geochemical samples by solid emission spectrometry was presented. The dedicated high content tin spectrum standard series was developed. K2S2O7, NaF, Al2O3 and carbon powder were used as buffers and Ge was used as internal standard, and the ratio of sample/matrixA method for the determination of high content of tin in geochemical samples by solid emission spectrometry was presented. The dedicated high content tin spectrum standard series was developed. K2S2O7, NaF, Al2O3 and carbon powder were used as buffers and Ge was used as internal standard, and the ratio of sample/matrix/buffer is 1∶1∶2. A weak sensitive line (Sn 242.170 0 nm) was used as the analytical line. The technologies of vertical electrodes, AC arc overlap spectrograph, interception of the exposure, quantitative computer translation spectrum and background correction were used. The determination range is 100~22 350 μg·g-1, the detection limit is 16.64 μg·g-1, and the precision is (RSD, n=12) 4.11%~6.46%. The accuracy of the method has been verified by determination of high content of tin in national geochemical standard samples and the results are in agreement with certified value. The method can be used for measurement directly without dilution of high content of tin in geochemical samples, and it greatly improved the detection upper limit for the determination of tin with solid emission spectroscopy and has certain practical value..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 3124 (2013)
Quantitative Surface Analysis of Pt-Co, Cu-Au and Cu-Ag Alloy Films by XPS and AES
LI Lian-zhong, ZHUO Shang-jun, SHEN Ru-xiang, QIAN Rong, and GAO Jie
In order to improve the quantitative analysis accuracy of AES, We associated XPS with AES and studied the method to reduce the error of AES quantitative analysis, selected Pt-Co, Cu-Au and Cu-Ag binary alloy thin-films as the samples, used XPS to correct AES quantitative analysis results by changing the auger sensitiviIn order to improve the quantitative analysis accuracy of AES, We associated XPS with AES and studied the method to reduce the error of AES quantitative analysis, selected Pt-Co, Cu-Au and Cu-Ag binary alloy thin-films as the samples, used XPS to correct AES quantitative analysis results by changing the auger sensitivity factors to make their quantitative analysis results more similar. Then we verified the accuracy of the quantitative analysis of AES when using the revised sensitivity factors by other samples with different composition ratio, and the results showed that the corrected relative sensitivity factors can reduce the error in quantitative analysis of AES to less than 10%. Peak defining is difficult in the form of the integral spectrum of AES analysis since choosing the starting point and ending point when determining the characteristic auger peak intensity area with great uncertainty, and to make analysis easier, we also processed data in the form of the differential spectrum, made quantitative analysis on the basis of peak to peak height instead of peak area, corrected the relative sensitivity factors, and verified the accuracy of quantitative analysis by the other samples with different composition ratio. The result showed that the analytical error in quantitative analysis of AES reduced to less than 9%. It showed that the accuracy of AES quantitative analysis can be highly improved by the way of associating XPS with AES to correct the auger sensitivity factors since the matrix effects are taken into account. Good consistency was presented, proving the feasibility of this method..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 3128 (2013)
Study of Arsenic Concentration and Distribution in Shell Sand of the Shell Ridge Islands by Hydride Generation Atomic Fluorescence Spectrometry
LIU Qing, ZHAO Xi-mei, XIE Wen-jun, SUN Jing-kuan, XIA Jiang-bao, and LU Zhao-hua
The present paper determined the As concentration in shell sand of the shell ridge islands by hydride generation atomic fluorescence spectrometry, studied the distribution of As in shell sand of the shell ridge islands, analysed the correlations of As with other nutrient elements, and discussed the probably influencingThe present paper determined the As concentration in shell sand of the shell ridge islands by hydride generation atomic fluorescence spectrometry, studied the distribution of As in shell sand of the shell ridge islands, analysed the correlations of As with other nutrient elements, and discussed the probably influencing factors affecting the As concentration and distribution in shell sand. The results showed that the range of the arsenic concentration in shell sand is between 0.78 and 8.76 mg·kg-1, the average concentration is 3.11 mg·kg-1, and this indicated that the As contamination of the shell ridge island is in clean level. The As concentration of the shell sand has a increasing trend followed by the increase with profile depth or the decrease with the particle size, and the difference in As concentrations in shell sand of different particle sizes reached the significant level (p≤0.05). The As concentration in shell sand has a very significant positive correlation with the concentrations of Cu, Zn and Mn as well as the TP and TK, whereas the correlations between As and TN or Fe are not significant. The pollutant of As in the shell sand mainly comes from the absorption and fixation by shell sand from the environment but not the accumulation of the shell organism during their growing up..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 3133 (2013)
Application of In Situ Micro Energy Dispersive X-Ray Fluorescence Analysis in Mineralogy
YANG Hai, GE Liang-quan, GU Yi, ZHANG Qing-xian, and XIONG Sheng-qing
Thirteen rock samples were collected for studying the variation of element content in the mineral during the alteration process from Xinjiang, China. The IED-6000 in situ micro energy dispersive X-ray fluorescence developed by CDUT was applied to get chemical and physical data from minerals. The non-destructive spectroThirteen rock samples were collected for studying the variation of element content in the mineral during the alteration process from Xinjiang, China. The IED-6000 in situ micro energy dispersive X-ray fluorescence developed by CDUT was applied to get chemical and physical data from minerals. The non-destructive spectrometer is based on a low-power Mo-anode X-ray tube and a Si-PIN peltier cooled X-ray detector. The unique design of the tube’s probe allows very close coupling of polycapillary and makes the use of micro-area measurement feasible and efficient. The spectrometer can be integrated into any microscope for analysis. The long axis diameter of beam spot is about 110 μm. According to micro-EDXRF measurement, the tetrahedrite was corrected to pyrite, improving the efficiency and accuracy of the mineral identification. The feldspar of mineralized rock sample is rich in Cu and Zn which can be used as prospecting indicator elements. Element content of Cr, Mn and Co shows negative correlation with the degree of mineralization..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 3137 (2013)
Study on XRD and Infrared Spectroscopy of Nephrites from Xinjiang and Xiuyan, Liaoning
CHEN Quan-li, BAO De-qing, and YIN Zuo-wei
The nephrite species with different colors from Xinjiang and Xiuyan, Liaoning, including gray nephrite, yellow nephrite, white nephrite, jasper and He-Mo nephrite, a special nephrite from Xiuyan, were selected for the present study. The gemological testing method, infrared absorption spectroscopy and X-ray powder diffrThe nephrite species with different colors from Xinjiang and Xiuyan, Liaoning, including gray nephrite, yellow nephrite, white nephrite, jasper and He-Mo nephrite, a special nephrite from Xiuyan, were selected for the present study. The gemological testing method, infrared absorption spectroscopy and X-ray powder diffraction were used to analyze and compare the gemological characteristics of the nephrite with different colors and textures from the above localities, in order to understand the similarities and differences between these nephrites with similar colors but different origin, and provide a theoretical basis for the identification of the nephrite origin. The results show that the nephrites from Xinjiang and Xiuyan, Liaoning province have similar gemological properties. They have similar refractive index of 1.60～1.62 and density of 2.660~3.020 g·cm-3, and only the density has some differences with different colors. The fluorescence characteristics are not obvious in these nephrites. The major constituent minerals for these nephrites are tremolite, and small amounts of clay minerals such as chlorite and illite are found in the jasper from Xinjiang. Based on the X-ray powder diffraction analysis on the different types of nephrite from two localities, it was shown that the character of spectra peaks and diffraction intensity of different types of nephrite can reflect the texture of the nephrite and the size of crystalline particles to some extent. The infrared absorption spectra are similar for the nephrites from two localities. The infrared absorption spectrum does not make sense to identify the origin and species of nephrites..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 3142 (2013)
Application of Confocal Micro-Beam X-Ray Fluorescence in Nondestructive Scanning Analysis of the Distribution of Elements in a Single Hair
LIU He-he, LIU Zhi-guo, SUN Tian-xi, PENG Song, ZHAO Wei-gang, SUN Wei-yuan, LI Yu-de, LIN Xiao-yan, ZHAO Guang-cui, LUO Ping, and DING Xun-liang
The confocal micro X-ray fluorescence (XRF) based on polycapillary X-ray lens and conventional X-ray source was used to carry out the scanning analysis of the distribution of the elements in a single hair. The elemental distribution in the single hair was obtained. In the confocal micro XRF technology, the output focalThe confocal micro X-ray fluorescence (XRF) based on polycapillary X-ray lens and conventional X-ray source was used to carry out the scanning analysis of the distribution of the elements in a single hair. The elemental distribution in the single hair was obtained. In the confocal micro XRF technology, the output focal spot of the polycapillary focusing X-ray lens and the input focal spot of the polycapillary parallel X-ray lens were adjusted confocally. The detector could only detect the X-rays from the overlapping foci. This confocal structure decreased the effects of the background on the X-ray spectra, and was accordingly helpful for improving the accuracy of this XRF technology. A polycapillary focusing X-ray lens with a high gain in power density was used to decrease the requirement of power of the X-ray source used in this confocal technology, and made it possible to perform such confocal micro XRF analysis by using the conventional X-ray source with low cost. Experimental results indicated that the confocal micro X-ray fluorescence based on polycapillary X-ray lens had potential applications in analyzing the elemental distribution of individual hairs..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 3147 (2013)
Study on Structure, Charge and Spectrum for Para-Halogenated Diphenyl Ethers through Density Functional Theory
JIANG Long, CAI Xiao-yu, ZHANG Chen, ZOU Qiao, and LI Yu
The present paper mainly researched the molecular geometry, charge distribution and spectrum vibration of diphenyl ether and its 3 kinds of para-halogenated diphenyl ethers based on density functional theory (DFT). The infrared and Raman spectrum vibration frequency for para-halogenated diphenyl ethers was calculated bThe present paper mainly researched the molecular geometry, charge distribution and spectrum vibration of diphenyl ether and its 3 kinds of para-halogenated diphenyl ethers based on density functional theory (DFT). The infrared and Raman spectrum vibration frequency for para-halogenated diphenyl ethers was calculated based on respective optimal molecular geometry with the same method which was carried out at the B3LYP/6-31(d) level, then spectrum vibration of para-halogenated diphenyl ethers was assigned in detail for the first time. Combined with charge distribution of diphenyl ether and by the nuclear magnetic resonance and Milliken charge distribution, the authors also analyzed the effect of different para-halogenated substituent on charge distribution, at last the vibration mechanism and change rule of of para-halogenated diphenyl ethers’ characteristic vibrations were analyzed in the view of charge distribution innovatively. From the research we can see that the more the electronegativity of para-halogenated substituent, the bigger the atomic radius, and the longer the C—X bond, the easier they are degraded in the environment; para-halogenated substituent affected the charge distribution greatly especially to para-carbon relative to ether bond, and meta-carbon was controlled by the combination electronic effect of para-halogenated substituent and oxygen atom, meanwhile ortho-carbon didn’t have distinct change; charge gap between bond atoms played significant role in the stability of bonds and vibration frequency of characteristic vibration, and the larger the electronegativity of para-halogenated substituent, the larger the vibration frequency..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 3151 (2013)
Optimizing the Method for 31P-NMR Analysis of Organic Phosphorus from Wetland Sediments
LU Jin, WANG Hai-wen, HAO Hong, GAO Bo, and JIA Jian-li
Solution 31P-Nuclear Magnetic Resonance (NMR) is an analysis technology which has been an effective means for the analysis of environmental organic phosphorus. However, the method is rarely applied in the study of wetlands so that the corresponding researches about wetland sediment sample preparation method also very dSolution 31P-Nuclear Magnetic Resonance (NMR) is an analysis technology which has been an effective means for the analysis of environmental organic phosphorus. However, the method is rarely applied in the study of wetlands so that the corresponding researches about wetland sediment sample preparation method also very deficient. The present study was aimed to find the most suitable sample preparation method for 31P-NMR analysis of the artificial wetland sediments, using different extractant (NaOH or 0.25 mol·L-1 NaOH+0.05 mol·L-1 EDTA as main extractant, and 1M HCl as pre-extractant or not), sample to extractant ratio (1∶8 or 1∶10), centrifugation conditions and scans time and so on. The results showed that the best 31P-NMR spectrum could be obtained with freeze-ried, ground and sieved sediments, 1M HCl as pre-extractant for 16 h, NaOH+0.05 mol·L-1 EDTA as main extractant for 16 h, extraction ratio of 1∶8, and low temperature and high-speed centrifugation (4 ℃, 10 000 r·min-1 for 30min) for avoiding hydrolysis of certain components. Besides, choosing much longer NMR scan time, as 14～16 h (scans about 25 000 times), could get more complete spectral signals spectrum. And finally, four kinds of P-compounds (orthophosphate, orthophosphate monoesters, orthophosphate diesters and pyrophosphate) were detected in the NMR spectrum. But neither polyphosphate nor phosphonates was not found in all these experiments, which need further study. Compared with the traditional chemical analysis method, 31P-NMR method of sample preparation is relatively simple. Then it is less destructive with components distinguished completely. Using 31P-NMR technology, the cognition of wetland phosphorus cycle, especially organophosphate, will be expected to get new breakthrough..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 3157 (2013)
Research on Influencing Factors and Compensation Method of Testing Results for Concave Gratings Diffraction Efficiency
CAO Hai-xia, Bayanheshig, CUI Ji-cheng, PAN Ming-zhong, and CHEN Shao-jie
The present paper aimed at the question that the beam cross-section changes according to the rotation of concave grating during the measuring process, and the appropriate supplement to the principle of the program was done. The appropriate supplement to the principle lay the foundation for the derivation of the beam crThe present paper aimed at the question that the beam cross-section changes according to the rotation of concave grating during the measuring process, and the appropriate supplement to the principle of the program was done. The appropriate supplement to the principle lay the foundation for the derivation of the beam cross-section k(θ), and the whole analytical expression of changes factor of the beam cross-section k(θ) for concave grating was derived. Because of the relationship between the theoretical values and the factors which affect the diffraction efficiency measuring accuracy was nonlinear, the quadratic nonlinear regression analysis was introduced and the compensating formula was established. The results show further correction to diffraction efficiency measurements for concave grating, the range of differences between the compensated values and the theoretical values was reduced from ±2.5% to less than ±0.3% , compared with the linear regression analysis, and the quadratic nonlinear regression analysis significantly reduces the variation between the compensated values and the theoretical values, which further ensures the accurate measurement of the diffraction efficiency for concave gratings. The compensating process is embedded in the measurement program; this method is strongly real-time, which can satisfy the requirements of simple operation, testing speediness and preciseness..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 3162 (2013)
[in Chinese]
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 11, 1 (2013)
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