Journals >Spectroscopy and Spectral Analysis
Contents
2013
Volume: 33 Issue 3
60 Article(s)
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Research Article
Low Temprature Properties of T Shape Photoacoustic Cell and Applications
NIU Ming-sheng, LIU Qiang, WANG Gui-shi, YUAN Yi-qian, HUANG Wei, ZHANG Wei-jun, and GAO Xiao-ming
A homemade low-temperature T shape photoacoustic system (PAS) in the range from 0 to -100 ℃ is well established. The mode distribution, the temperature dependence of the resonant frequency, Q-factor and the sensitivity of the PAS were investigated. The measurement of the carbon dioxide in the range from 0 to -100 ℃ shoA homemade low-temperature T shape photoacoustic system (PAS) in the range from 0 to -100 ℃ is well established. The mode distribution, the temperature dependence of the resonant frequency, Q-factor and the sensitivity of the PAS were investigated. The measurement of the carbon dioxide in the range from 0 to -100 ℃ showed that the system can be used in trace gas detection under low-temperature. The results show that the PAS can be used to study the atmospheric molecules continuous absorption at low-temperature..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 577 (2013)
Study on THz Spectra and Vibrational Modes of Benzoic Acid and Sodium Benzoate
ZHENG Zhuan-ping, FAN Wen-hui, YAN Hui, LIU Jia, and XU Li-min
Terahertz time-domain spectroscopy was employed to measure the terahertz absorption spectra of benzoic acid and sodium benzoate at room temperature. The origins of the measured features of benzoic acid were summarized based on previous study. Density functional theory was used to compute and analyze the molecular strucTerahertz time-domain spectroscopy was employed to measure the terahertz absorption spectra of benzoic acid and sodium benzoate at room temperature. The origins of the measured features of benzoic acid were summarized based on previous study. Density functional theory was used to compute and analyze the molecular structure and vibrational modes of sodium benzoate in monomer. Based on the obtained results, the authors found that the THz spectral features can be used to distinguish benzoic acid and sodium benzoate totally; the essential reason for the THz spectral difference between benzoic acid and sodium benzoate is that the electrovalent bond of sodium benzoate affects the values of covalent bond lengths and bond angles, as well as the molecular interactions and arrangement in unit cell; the measured features of benzoic acid and sodium benzoate come from the collective vibrations except the peaks located at 107 cm-1 of benzoic acid and 54 cm-1 of sodium benzoate..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 582 (2013)
The Characteristics and Dielectric Dynamics of Hydrated TiO2 in THz Frequency Range
JIANG Yu, HUANG Wan-xia, SHI Qi-wu, LUO Yi, and ZHANG Ya-xin
Terahertz time-domain spectroscopy (THz-TDS) was used to measure the information of water, the terahertz time-domain and frequency spectroscopy, absorbance, refractive index and the complex dielectric permittivity in the frequency range of 0.2～1 THz of various hydrated TiO2 samples with heating for different times. TheTerahertz time-domain spectroscopy (THz-TDS) was used to measure the information of water, the terahertz time-domain and frequency spectroscopy, absorbance, refractive index and the complex dielectric permittivity in the frequency range of 0.2～1 THz of various hydrated TiO2 samples with heating for different times. The result reveals that the absorbance of hydrated TiO2 reduces with heating time increasing, and the location of the absorption peak is corresponded to the refractive index. The response of electric polarization in THz field has no clear relations with the frequency. With frequency increasing, the dielectric dissipation of hydrated TiO2 firstly decreases and then tends to be stable. The dielectric response always reduces with heating time increasing..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 586 (2013)
EIT and MOLLOW Spectrum in N-Type Four-Level System
LI Xiao-li, MENG Xu-dong, YANG Zi-cai, and SUN Jiang
An N-type four level system where two coupling fields interact with two separate optical transitions was constructed in the present paper. By discussing the behaviors of probing field absorption profiles under the effect of different Rabi frequencies of two coupling fields, EIT, Mollow and Autler-Townes doublet can be An N-type four level system where two coupling fields interact with two separate optical transitions was constructed in the present paper. By discussing the behaviors of probing field absorption profiles under the effect of different Rabi frequencies of two coupling fields, EIT, Mollow and Autler-Townes doublet can be seen and mutual transformation between them can be obtained. Multiple transition channels in the system were found and the results show that the system can be divided into several subsystems according to the transition channels. Quantum interference between different transition channels can be realized through different dividing methods, so three nonlinear effects with different generating conditions and physical nature can be seen in the system..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 590 (2013)
Spectrum Diagnostics for the Time of Pre-Sputtering in Thin Films Deposited by Magnetron Puttering
GUO Qing-lin, FAN Qing, CUI Yong-liang, DONG Kai-hu, ZHANG Lei, LI Xu, ZHANG Jin-ping, and CHEN Jin-zhong
A plasma analysis system comprised of Omni-λ300 series grating spectrometer, CCD data acquisition system and optical fiber transmission system was utilized in the present paper to realize the real-time acquisition of plasma emission spectra during the process of radio frequency (RF) magnetron sputtering. The plasma emiA plasma analysis system comprised of Omni-λ300 series grating spectrometer, CCD data acquisition system and optical fiber transmission system was utilized in the present paper to realize the real-time acquisition of plasma emission spectra during the process of radio frequency (RF) magnetron sputtering. The plasma emission spectra produced by NiTa, TiAl ceramic targets and NiAl, TiAl alloy targets were monitored respectively, in addition, the behavior of analysis lines of TaⅡ333.991 nm, NiⅠ362.473 nm, AlⅠ396.153 nm and TiⅠ398.176 nm with time was obtained, according to which the time of pre-sputtering of the four kinds of target materials was fixed. At the same time, for the TiAl alloy target as the research object, the influence of different powers and pressures on the time of pre-sputtering was studied..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 595 (2013)
Multi-Angular Polarized Characteristics of Ocean Aerosol
CHEN Wei, YAN Lei, and YANG Shang-qiang
Ocean aerosol is an important component of troposphere aerosol, playing an important role in the global radiative balance and global climate change. To evaluate the direct and indirect radiative effects of aerosol needs deep research on aerosol properties. Multi-angular polarization provides a new method to retrieve aeOcean aerosol is an important component of troposphere aerosol, playing an important role in the global radiative balance and global climate change. To evaluate the direct and indirect radiative effects of aerosol needs deep research on aerosol properties. Multi-angular polarization provides a new method to retrieve aerosol optic and microphysical properties of aerosol. On the basis of the research on optic properties of ocean aerosol at the wavelength of 550 and 860 nm, a vector radiative transfer model was used to simulate the reflectance and polarized reflectance at the top of atmosphere. The sensitivity of reflectance and polarized reflectance to underlying surface, viewing azimuth and aerosol optic depth are evaluated. The simulation results show that the multi-angular polarization information could effectively provide information about the ocean aerosol, which suggests a useful way for ocean aerosol retrieval. Based on the studies of sensitivity, the theory of using multi-angular polarized remote sensing data to retrieve aerosol information is proposed..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 600 (2013)
Study on Large-Scale Regional Laser Detection Methods for Water Vapor Concentration
HE Ying, ZHANG Yu-jun, WANG Li-ming, YOU Kun, ZHOU Yi, SUN Xiao-min, and LIU Zhen-min
Water vapor is an important meteorological parameter in the atmosphere, TDLAS direct absorption technology combined with open-path monitoring was used in order to achieve large-scale regional atmospheric water vapor concentration detection with high sensitivity, high accuracy and fast response, and to correct the remotWater vapor is an important meteorological parameter in the atmosphere, TDLAS direct absorption technology combined with open-path monitoring was used in order to achieve large-scale regional atmospheric water vapor concentration detection with high sensitivity, high accuracy and fast response, and to correct the remote sensing data. The large-scale regional laser detection system for water vapor was designed and the absorption line of water vapor molecules near 1.27 μm was chosen as the goal line. The system performance was verified in conjunction with a multiple reflection cell, that the system limit sensitivity was 14.803 mmol·mol-1 in optical path of 40 m. The continuous field experiment in 1 420 m optical path at the Yucheng Integrated Experimental Station, CAS was completed with this system which worked stably. Then the measured data was compared with the data of a gas analyzer LI-7500 in eddy correlation observation system at the same site, and the data consistency was good. A new method for water vapor concentration monitoring in the complex field of non-uniform underlying surface was provided..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 608 (2013)
Study on the Fine Structure of K-Feldspar of Qichun Granite
DU Deng-wen, HONG Han-lie, FAN Kan, WANG Chao-wen, and YIN Ke
Fine structure of K-feldspar from the Qichun granite was investigated using X-ray diffraction (XRD), Fourier infrared absorption spectroscopy (FTIR), and inductively coupled plasma mass spectrometry methods to understand the evolution of the granitic magmatism and its correlation to molybdenite mineralization. The XRD Fine structure of K-feldspar from the Qichun granite was investigated using X-ray diffraction (XRD), Fourier infrared absorption spectroscopy (FTIR), and inductively coupled plasma mass spectrometry methods to understand the evolution of the granitic magmatism and its correlation to molybdenite mineralization. The XRD results showed that K-feldspar of the potassic alteration veins has higher ordering index and triclinicity and is namely microcline with triclinic symmetry. K-feldspar of the early cretaceous granite has relatively lower ordering index and has widening ［131］ peak and is locally triclinic ordering. K-feldspar of the late cretaceous granite has lowest ordering index and sharp ［131］ peak and is homogeneously monoclinic. The FTIR results showed that the IR spectra of the Qichun K-feldspar are similar to that of orthoclase reported by Farmer (1974). The 640 cm-1 absorption band increases while the 540 cm-1 absorption band decreases with increase in K-feldspar ordering index, also, the 1 010 cm-1 absorption band separates into 1 010 and 1 046 cm-1 absorption bands, with a change in the band shape from widening to sharp outline. The ICP-MS results suggested that K-feldspar of the early cretaceous granite has relatively higher metal elements and rare earth elements, and the granite exhibits better mineralization background, K-feldspar of the potassic alteration veins has markedly lower Sr and Ba, indicating that the alteration fluid originated from the granitic magmatism, and hence, potassic alteration is a good indicator for molybdenite exploration..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 613 (2013)
The Relationship Between the Variation Rate of MODIS Land Surface Temperature and AMSR-E Soil Moisture and Its Application to
WANG An-qi, XIE Chao, SHI Jian-cheng, and GONG Hui-li
Using AMSR-E soil moisture, MODIS land surface temperature (Ts) and vegetation index product, the authors discuss the relationship between the variation rate of land surface temperature and surface soil moisture. Selecting the plains region of central United States as the study area, the authors propose the distributioUsing AMSR-E soil moisture, MODIS land surface temperature (Ts) and vegetation index product, the authors discuss the relationship between the variation rate of land surface temperature and surface soil moisture. Selecting the plains region of central United States as the study area, the authors propose the distribution triangle of the variation rate of land surface temperature and soil moisture. In the present paper, temperature variation and vegetation index (TVVI), a new index containing the information of temperature variation and vegetation, is introduced. The authors prove that TVVI and soil moisture show a steady relationship of exponential function; and build a quantitative model of soil moisture(SM) and instantaneous surface temperature variation (VTs). The authors later achieve downscaling of AMSR-E soil moisture data, through the above stated functional relationships and high-resolution MODIS data. Comparison with measured data on ground surface indicates that this method of downscaling is of high precision..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 623 (2013)
Synthesis and Properties of Nano-Rutile TiO2 Photocatalysts
LI Hui-quan, XU Bo-lian, FAN Yi-ning, YANG Han-pei, and HONG Wen-shan
Nano-rutile TiO2 photocatalysts with bigger specific surface area were prepared by a hydrolysis method at 323 K, and characterized by X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), ultraviolet-visible diffuse reflection spectroscopy (UV-Vis DRS), infrared spectroscopy (IR) and photoelectrochemical (PEC). The ulNano-rutile TiO2 photocatalysts with bigger specific surface area were prepared by a hydrolysis method at 323 K, and characterized by X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), ultraviolet-visible diffuse reflection spectroscopy (UV-Vis DRS), infrared spectroscopy (IR) and photoelectrochemical (PEC). The ultraviolet (UV) and visible light photocatalytic activities of as-prepared rutile and anatase TiO2 nano-photocatalysts with almost same specific surface areas were evaluated by methyl orange (MO) as mode compound to photocatalytic reaction. The results of the photocatalytic experiment shows that when rutile and anatase have the similar specific surface area of ～95 m2·g-1, the UV light photocatalytic activity of rutile is comparable to that of anatase, while rutile shows significantly higher visible light photocatalytic activities than anatase. The photoelectrochemical experiment shows that the order of photocurrent densities of the catalysts from weak to strong is in accordance with the order of UV light photocatalytic activities of the catalysts from low to high under UV light irradiation..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 628 (2013)
The Color Analysis of Peacock Feather
ZHANG Qing-yue, L Hao1, ZHAO Qiu-ling, and WANG Xia
Peacock feather is one of the typical cases with structural colors. In the present article, we found that flamboyant colors in the “eye spot” of male peacock came from photonic crystal structure by observing the surface texture with SEM and reflectance spectrum with fiber spectrometer, and different color regions correPeacock feather is one of the typical cases with structural colors. In the present article, we found that flamboyant colors in the “eye spot” of male peacock came from photonic crystal structure by observing the surface texture with SEM and reflectance spectrum with fiber spectrometer, and different color regions correspond to various structure cycles and surface appearances of the microstructure. The reflectance spectrum showed that the location of reflective peak shifted with the changes in the incident angles. The theory that the color is caused by microstructure was verified by the phenomenon that reflective peak exhibited red-shift with the time-varying after soaking in isopropyl alcohol. This study paves the way for fabricating functional composite materials with peacock feather-like photonic crystal structure..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 632 (2013)
Spectral Characteristics of White Organic Light-Emitting Devices Based on Phosphorescent System of Three Iridium Chelates
LIU Sheng-qiang, YU Jun-sheng, ZENG Yan-bo, ZHAO Juan, and DU Chun-lei
A white organic light-emitting device (WOLED) with a yellow phosphorescence material, bis［2-(4-tertbutylphenyl)benzothiazolato-N,C2’］ iridium (acetylacetonate) ［(t-bt)2Ir(acac)］, and two blue phosphorescence materials, iridium(Ⅲ) bis(4’,6’-difluorophenylpyridinato)tetrakis(1-pyrazolyl)borate (FIr6) and bis［(4,6-difluorA white organic light-emitting device (WOLED) with a yellow phosphorescence material, bis［2-(4-tertbutylphenyl)benzothiazolato-N,C2’］ iridium (acetylacetonate) ［(t-bt)2Ir(acac)］, and two blue phosphorescence materials, iridium(Ⅲ) bis(4’,6’-difluorophenylpyridinato)tetrakis(1-pyrazolyl)borate (FIr6) and bis［(4,6-difluorophenyl)-pyridinato-N,C2’］(picolinate) iridium (Ⅲ) (FIrpic), were fabricated. Stable white emission was realized by using undoped ultrathin yellow emissive layer (EML), two doped blue EMLs together with the proper thickness of an interlayer confining the exciton. The WOLED performed pure white light emission with the Commissions Internationale de l’Eclairage (CIE) coordinates of (0.29±0.01, 0.34±0.01) from 6 to 14 V. Moreover, electroluminescence (EL) characteristics of the devices were also studied to verify the emissive mechanism from a phosphorescent system consisting of three iridium chelates. Also, the results showed that the triple-phosphor-element EMLs WOLED had lower efficiency roll-off owing to the stable recombination zone..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 636 (2013)
Preparation, Characterization and Upconversion Fluorescence of NaYF4∶Yb, Er /Graphene Oxide Nanocomposites
JI Tian-hao, QIE Nan, WANG Ji-mei, HUA Yong-yong, and JI Zhi-jiang
NaYF4∶Yb, Er/rGO and SiO2-coated NaYF4∶Yb, Er/rGO nanocomposites can be prepared through “one-pot” and directly mixing preparation routes. Various measurement results show that the NaYF4∶Yb, Er in the nanocomposites exhibits a cubic α-type structure and nanoparticle-like morphology with a diameter range of 30～70 nm; thNaYF4∶Yb, Er/rGO and SiO2-coated NaYF4∶Yb, Er/rGO nanocomposites can be prepared through “one-pot” and directly mixing preparation routes. Various measurement results show that the NaYF4∶Yb, Er in the nanocomposites exhibits a cubic α-type structure and nanoparticle-like morphology with a diameter range of 30～70 nm; the rGO layers are well-dispersed in the nanocomposites, and whereas the rGO obtained from “one-pot” preparation renders relatively better dispersion. Raman spectra demonstrate that there exists a surface coupling action between the two kinds of nanomaterials, and with the increase in the relative rGO content, such action becomes stronger. UC fluorescence measurement results reveal that the rGO has significantly quenching effect and optical-limiting performance on the UC fluorescence, particularly on the red-emission of the NaYF4∶Yb, Er or SiO2-coated NaYF4∶Yb, Er nanoparticles. The red-emission intensity gradually decreases with an increase in the rGO content, but the green-emission shows less change. It should be stressed that in comparison with NaYF4∶Yb, Er/rGO, with a similar rGO content, the red-emission intensity of SiO2-coated NaYF4∶Yb, Er/rGO decreases much obviously due to a stronger light-absorption caused by part rGO aggregation..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 642 (2013)
The Curing Behavior of Two Thermoset Resins Containing Silicon Alkynyl Group
SHI Song, KONG Lei, QI Hui-min, and ZHANG Da-hai
In the present report, the curing behavior of two thermoset resins containing silicon alkynyl group- PAR and PMR, and the correlation between the curing structure of resin and their thermal stability were investigated by FTIR, 13C NMR, DSC and TGA techniques. The IR and NMR results showed that the curing mechanism of PIn the present report, the curing behavior of two thermoset resins containing silicon alkynyl group- PAR and PMR, and the correlation between the curing structure of resin and their thermal stability were investigated by FTIR, 13C NMR, DSC and TGA techniques. The IR and NMR results showed that the curing mechanism of PAR and PMR resin is different. Based on aromatic cyclization among alkynyl groups and Diels-Alder reaction, aromatic frame network structure constituted by benzene cycles and condensed aromatic cycles are formed in the PAR cured resin. Using additional reaction among Si—H group, alkynyl group and alkenyl group, saturated Si—C(sp3) network structure is formed in the PMR cured resin. The aromatic frame network structure and Si—C(sp3) network structure provide good thermal stability for PAR and PMR resin respectively. The thermal decomposition temperatures Td5 of both resins are above 600 ℃, and the residues percentages at 900 ℃ are above 85%..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 647 (2013)
Application of Excitation-Emission Matrix Spectrum Combined with Parallel Factor Analysis in Dissolved Organic Matter in East China Sea
L Li-sha, ZHAO Wei-hong, and MIAO Hui
Using excitation-emission matrix spectrum(EEMs) combined with parallel factor analysis(PARAFAC) examine the fluorescent components feature of dissolved organic matter (DOM) sampled from East China Sea in the summer and autumn was examined. The type, distribution and origin of the fluorescence dissolved organic matter wUsing excitation-emission matrix spectrum(EEMs) combined with parallel factor analysis(PARAFAC) examine the fluorescent components feature of dissolved organic matter (DOM) sampled from East China Sea in the summer and autumn was examined. The type, distribution and origin of the fluorescence dissolved organic matter were also discussed. Three fluorescent components were identified by PARAFAC, including protein-like component C1(235, 280/330), terrestrial or marine humic-like component C2(255, 330/400) and terrestrial humic-like component C3(275, 360/480). The good linearity of the two humic-like components showed the same source or some relationship between the chemical constitutions. As a whole, the level of the fluorescence intensity in coastal ocean was higher than that of the open ocean in different water layers in two seasons. The relationship of three components with chlorophyll-a and salinity showed the DOM in the study area is almost not influenced by the living algal matter, but the fresh water outflow of the Yangtze River might be the source of them in the Yangtze River estuary in Summer. From what has been discussed above, we can draw the conclusion that the application of EEM-PARAFAC modeling will exert a profound influence upon the research of the dissolved organic matter..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 653 (2013)
Investigations of Fluorescence Spectral Correction for a Two-Component Mixed Solution with Overlapping Absorption Spectra
CHEN Xiang-dong, GAO Feng, WU Ben-ke, CHENG Ping, and YANG Ji-ping
The inner filter effect (IFE) and the absorption depth from the fluorescence material will directly lead to an artifact for intensity and spectral shape of the fluorescence spectra, and they restrict the application of fluorescence analysis. A two-component mixed solution with overlapping absorption spectra was used toThe inner filter effect (IFE) and the absorption depth from the fluorescence material will directly lead to an artifact for intensity and spectral shape of the fluorescence spectra, and they restrict the application of fluorescence analysis. A two-component mixed solution with overlapping absorption spectra was used to develop a new method based on physical absorption model to correct the influences of IFE and the absorption depth on fluorescence intensity. The spectral investigations of terthiophene/quinquethiophene mixture solution show that a good correction result can be obtained by using the above correction method, and the error after correction is less than 5%..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 659 (2013)
Fluorescent Labeling of Latent Fingerprints with Metallic Ions Modified ZnS/PAMAM Nano-Composites
JIN Yu-juan, DUAN Xiao-bo, LIN Yu-meng, and WANG Si-kun
Effects of metallic ions, such as Zn2+, Mn2+, Cd2+, Na+, K+, Ag+, Cu2+ and Pb2+, on the photoluminescence properties of ZnS(ZINC sulfide) QDs (quantum dots)/poly(amido amine)(PAMAM) dendrimer nanocomposites(NCs) with blue emission under the irradiation of UV light were studied. The results show that the effects of diffEffects of metallic ions, such as Zn2+, Mn2+, Cd2+, Na+, K+, Ag+, Cu2+ and Pb2+, on the photoluminescence properties of ZnS(ZINC sulfide) QDs (quantum dots)/poly(amido amine)(PAMAM) dendrimer nanocomposites(NCs) with blue emission under the irradiation of UV light were studied. The results show that the effects of different metallic ions on the photoluminescence properties of the prepared ZnS QDs were different. Zn2+, Mn2+ and Cd2+ ions enhance the PL(photoluminescence) intensity; Na+ and K+ ions don’t change the PL intensity obviously while Ag+, Cu2+ and Pb2+ quench it. Compared with ZnS/PAMAM NCs, fingerprints treated with ZnxCd(1-x)S/PAMAM NCs emitted brighter blue light, the contrast between abstracts and fingerprints was more obvious, which shows good reference value for enhancing the resolving ability of fingerprints..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 663 (2013)
Study on Experiment of Fluorescence Spectra Detection of Pesticide Residue of Imidacloprid in Apple Juices
JI Ren-dong, ZHAO Zhi-min, ZHANG Lin, JI Lei, ZHANG Ji-hua, SHEN Ling-bin, and LAN Xiu-feng
The fluorescence properties of imidacloprid was studied based on the basic theory that organic molecules can emit fluorescence as they are excited by rays. The fluorescence spectra were obtained under the condition of different content of imidacloprid in apple juices and pure apple juices respectively through fluoresceThe fluorescence properties of imidacloprid was studied based on the basic theory that organic molecules can emit fluorescence as they are excited by rays. The fluorescence spectra were obtained under the condition of different content of imidacloprid in apple juices and pure apple juices respectively through fluorescence spectrometer, and the relation between their fluorescence intensity and content of imidacloprid was analyzed. The experiment results show that the most intensive fluorescence (373 nm) was found in the spectrum of imidacloprid, while the fluorescence was not found in the pure apple juices with 234 nm as the excitation wavelength. Then the imidacloprid solution was added to the fruit juices increasingly. The best prediction model was obtained for the contend of imidacloprid in the apple juices, the coefficient of determination is 0.996 74, and the accuracy is higher than 90%. As a result, it is fast and feasible to carry out the detection and analysis of the pesticide residue of imidacloprid in the apple juices..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 668 (2013)
Study on Mechanism of Inactivated Cider Yeast Adsorbing Patulin by Fourier Transform Infrared Spectroscopy
GUO Cai-xia, YUE Tian-li, YUAN Ya-hong, WANG Zhou-li, WANG Ling, and CAI Rui
The mechanism of patulin adsorption by inactivated cider yeast was studied by chemical modification and FTIR. The results of patulin removal by various modified yeast biomass showed that the ability of patulin biosorption by acetone-treated yeast and NaOH-treated yeast increased siginificantly, while the methylation ofThe mechanism of patulin adsorption by inactivated cider yeast was studied by chemical modification and FTIR. The results of patulin removal by various modified yeast biomass showed that the ability of patulin biosorption by acetone-treated yeast and NaOH-treated yeast increased siginificantly, while the methylation of amino group and esterification of carboxylate functionalities of yeast cell surface caused a decrease in patulin binding, which indicated that amino group and carboxyl group presented in the cell walls of yeast might be involved in the binding of patulin to the yeast. The FTIR analysis indicated that the main functional groups were amino group, carboxyl group and hydroxy group which are associated with protein and polysaccharides..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 672 (2013)
Effect of Soil Moisture on Prediction of Soil Total Nitrogen Using NIR Spectroscopy
AN Xiao-fei, LI Min-zan, ZHENG Li-hua, LIU Yu-meng, and SUN Hong
As one of the most important components of soil nutrient, it is necessary to obtain the soil total nitrogen（STN）content in precision agriculture. It is a feasible method to predict soil total nitrogen content based on NIRS. However, the effect of soil moisture content (SMC) on the prediction of STN is very serious. In As one of the most important components of soil nutrient, it is necessary to obtain the soil total nitrogen（STN）content in precision agriculture. It is a feasible method to predict soil total nitrogen content based on NIRS. However, the effect of soil moisture content (SMC) on the prediction of STN is very serious. In the present research, the effect of SMC was discussed from qualitative analysis and quantitative analysis by the Fourier spectrum analyzer MATRIX_I. Firstly, sixty soil samples with different STN and SMC were scanned by the MATRIX_I. It was found that the reflectance of soil samples in near infrared region decreased with the increase in SMC. Subsequently, Moisture absorbance index (MAI) was proposed by the diffuse of absorbance at the wavelengths of 1 450 and 1 940 nm to classify soil properties and then correction factor was present. Finally, the STN forecasting model with BP NN method was established by the revised absorbance data at the six wavelengths of 940, 1 050, 1 100, 1 200, 1 300 and 1 550 nm. The model was evaluated by correlation coefficient of RC, correlation coefficient of RV, root mean square error of calibration (RMSEC), root mean square error of validation (RMSEP) and residual prediction deviation (RPD). Compared with the model obtained from original spectral data, both the accuracy and the stability were improved. The new model was with RC of 0.86, RV of 0.81, RMSEC of 0.06, RMSEP of 0.05, and RPD of 2.75. With the first derivative of the revised absorbance, the RPD became 2.90. The experiments indicated that the method could eliminate the effect of SMC on the prediction of STN efficiently..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 677 (2013)
Rapid Prediction of Surface Roughness of Natural Polymer Material by Visible/Near Infrared Spectroscopy as a Non-Contact Measurement Method
YANG Zhong, LIU Ya-na, L Bin, and ZHANG Mao-mao
In order to investigate the feasibility of visible/Near Infrared(Vis-NIR)spectroscopy to predict the surface roughness of natural polymer material(wood) as a non-contact measurement method,the correlations between Vis-NIR spectroscopy and surface roughness measured by contact(stylus) instruments from three different seIn order to investigate the feasibility of visible/Near Infrared(Vis-NIR)spectroscopy to predict the surface roughness of natural polymer material(wood) as a non-contact measurement method,the correlations between Vis-NIR spectroscopy and surface roughness measured by contact(stylus) instruments from three different sections of wood samples were analyzed. The results showed that the surface roughness parameters, arithmetical mean deviation of profile (Ra), ten-point height of irregularities (Rz) and the maximum height of profile (Ry), of wood samples were successfully predicted by using Vis-NIR (400~2 500 nm) models from the three sections of the samples. The correlations between values measured by the stylus instruments and the values predicted by the models were good. The correlation coefficients of Rz reached up to 0.92. Compared to the models based on the Vis-NIR from the radial section and tangential section of the samples, the predictive effect of the model based on cross section was the best. The correlation coefficients between the values measured by the stylus instruments and the values predicted by the models based on different spectrum wavelength range, 400~780, 780~1 100, 1 100~2 500, 780~2 500 and 400~2 500 nm, were generally above 0.80. The prediction results of the model based on spectrum wavelength range 400~2 500 nm was better than the models based on the other spectrum wavelength ranges. The results showed that the predictive effect was not improved by pretreatment of the spectrum. It is proposed to use the original spectrum to predict the surface roughness of natural polymer material..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 682 (2013)
Synchrotron Radiation-Based FTIR Microspectroscopy Study of 6-Hydroxydopamine Induced Parkinson’s Disease Cell Model
ZHU Hong-yan, PEI Xiao, WU Ling-yan, QI Ze-ming, WANG Yu-yin, LIU Bo, and ZHOU Hou-guang
SH-SY5Y cell line treated with 6-hydroxydopamine (6-OHDA) is a classical Parkinson’s disease (PD). In the present study, synchrotron-based Fourier transform infrared (FTIR) microspectroscopy was used to analyze the biochemical composition of SH-SY5Y cell line treated with 6-OHDA. The detailed spectral analyses show theSH-SY5Y cell line treated with 6-hydroxydopamine (6-OHDA) is a classical Parkinson’s disease (PD). In the present study, synchrotron-based Fourier transform infrared (FTIR) microspectroscopy was used to analyze the biochemical composition of SH-SY5Y cell line treated with 6-OHDA. The detailed spectral analyses show the significant changes in cellular compositions such as lipids, proteins and nucleic acids in SH-SY5Y cells treated with 6-OHDA compared to control SH-SY5Y cells. As a result, the unsaturation levels of phospholipids decrease in SH-SY5Y cells treated with 6-OHDA compared to control cells, the analysis of protein secondary structure shows the significantly higher ratio of β-sheet in PD cells compared to that of control cells, and the content of nuclear acid is highly decreased compared to that of control cells, suggesting that 6-OHDA induces the serious oxidative damage in SH-SY5Y cells. These findings suggest that SR-FTIR is an effective and precise technical tool to probe the biochemical changes of cells and then evaluate the pathological damage in cells..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 686 (2013)
Detection of Plasticizers in Edible Essence by Near-Infrared Spectrometry
LI Xiang-hui, YANG Fang, LIN Zhen-yu, QIU Bin, and WANG Dan-hong
Based on the initial near-infrared spectrum of edible essence samples and its mixture with DEHP and DINP, we chose the wavelength ranges of 8 800～8 540 and 7 500～5 085 cm-1 to use the principal component analysis (PCA) method to distinguish these three types of samples. The correct rate of the identification is proved Based on the initial near-infrared spectrum of edible essence samples and its mixture with DEHP and DINP, we chose the wavelength ranges of 8 800～8 540 and 7 500～5 085 cm-1 to use the principal component analysis (PCA) method to distinguish these three types of samples. The correct rate of the identification is proved to be 100%. Meanwhile, we measured the content of DEHP and DINP (with the concentration ranging between 0 and 100 mg·kg-1) in the edible essence and established the quantitative analysis model by using partial least squares (PLS). It was found that the relative errors of the prediction results of DEHP and DINP are －1.23%～3% and －1%～3.6%, respectively, and the relative root-mean-square errors of prediction (RRMSEP) of them are 1.39 and 0.98, respectively. This study provides a simple, rapid and accurate method to detect the additive dosage of plasticizing agents in edible essence in the food industry..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 690 (2013)
Research Progress in Raman Spectra and Its Test Sample Pretreatment
WEI Na, FENG Xu-qiao, ZHANG Xiao-fang, QI Xiao-hua, ZOU Ming-qiang, and WANG Ming-tai
It is generally accepted that Raman spectroscopy is an advanced method with simple operation, small amount of specimens needed as well as rapid on-line screening, detection and identification. However, in the technology of determination, sample preparation is also an significant factor during analysis process. It wouldIt is generally accepted that Raman spectroscopy is an advanced method with simple operation, small amount of specimens needed as well as rapid on-line screening, detection and identification. However, in the technology of determination, sample preparation is also an significant factor during analysis process. It would affect the accuracy and precision of the results, and normally involved complicated procedure. Developing a rapid and effective sample preparation method coupled with Raman detective technology is a method worth study. In the present paper, the simply basic principle, the origin and development of generating Raman spectra were introduced, some Raman technology, such as the surface-enhanced Raman spectroscopy, tip-enhanced Raman spectroscopy, shell-isolated nanoparticle enhanced Raman spectroscopy and the sample preparation were discussed..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 694 (2013)
Raman Spectra Analysis of GaN∶Er Films Prepared by Ion Implantation
TAO Dong-yan, LIU Chao, YIN Chun-hai, and ZENG Yi-ping
U-, n- and p-GaN∶Er films were prepared by ion implantation method. Three carrier types of samples were studied by Raman spectra analysis. After Er+ ion implantation into GaN samples, new Raman peaks at wavenumber of 293, 362和670 cm-1 appeared, where 293 cm-1 was considered as disordered activation of Raman scattering U-, n- and p-GaN∶Er films were prepared by ion implantation method. Three carrier types of samples were studied by Raman spectra analysis. After Er+ ion implantation into GaN samples, new Raman peaks at wavenumber of 293, 362和670 cm-1 appeared, where 293 cm-1 was considered as disordered activation of Raman scattering (DARS), 362 and 670 cm-1 may be associated with GaN lattice defects formed after ion implantation. The E2 (high) characteristic peak moves to the high frequency before and after GaN∶Er samples annealing at 800 ℃, indicating that GaN lattice is under the compressive stress. The Lorenz fitting was used to analysed the occurrences of A1(LO) peak in different samples which is composed of the uncoupled mode LO and the plasmon coupling mode LPP+, qualitatively pointing out the carrier concentration variation of a series of GaN∶Er samples..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 699 (2013)
Raman and Infrared Spectrograms of Organic Borate Intercalated Hydrotalcite
ZHANG Jing-yu, BAI Zhi-min, and ZHAO Dong
The pattern of X-ray diffraction, the Raman and infrared spectra of organic borate intercalated hydrotalcite were discussed. The well crystallized zinc-aluminum layered double hydroxides (Zn-Al LDHs) intercalated by carbonate ions and borate ions were respectively prepared by co-precipitation method. Patterns of X-ray The pattern of X-ray diffraction, the Raman and infrared spectra of organic borate intercalated hydrotalcite were discussed. The well crystallized zinc-aluminum layered double hydroxides (Zn-Al LDHs) intercalated by carbonate ions and borate ions were respectively prepared by co-precipitation method. Patterns of X-ray diffraction showed that the (003) reflection of borate-LDHs was sharp and symmetric and shifted to lower angle than that of carbonate-LDHs. The gallery height of borate-LDHs increased from 0.28 nm to 0.42 nm after intercalation, indicating that interlayered carbonate ions were substituted by borate anions. The Raman and IR spectra showed that specific bands of carbonate ions in the borate-LDHs disappeared, but with the presence of B3O3(OH)-4, B4O5(OH)2-4 and B(OH)-4 in the interlayer galleries. The hydroxide interlayer anions had a significant influence on the band positions in Raman and infrared spectra of modes related to the hydroxyl group. Our results indicate that single phase and pure borate-pillared LDHs can be obtained using tributyl orthoborate as intercalating agents, and the change in the structure and nature of hydrotalcite can be detected precisely by Raman spectroscopy..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 704 (2013)
Alkaline Silver Colloid for Surface Enhanced Raman Scattering and Application to Detection of Melamine Doped Milk
TANG Jun-qi, TIAN Chao, ZENG Chong-yi, and MAN Shi-qing
Alkaline silver colloid with better stability and uniformity was obtained by adding appropriate amount of NaOH to synthesis reaction. The performance of the Ag colloid as surface enhanced Raman scattering (SERS) active substrate was evaluated by methylene blue as the probe molecules and achieved well Raman spectra. TheAlkaline silver colloid with better stability and uniformity was obtained by adding appropriate amount of NaOH to synthesis reaction. The performance of the Ag colloid as surface enhanced Raman scattering (SERS) active substrate was evaluated by methylene blue as the probe molecules and achieved well Raman spectra. The concentration of methylene blue had no effect on the adsorptive behavior of methylene blue on alkaline silver colloid surface in comparison with normal silver colloid. The basic reason for this phenomenon is preferential adsorption of alkaline silver colloid for sulfur atoms of methylene blue so as to increase the intensity of 451 cm-1 Raman peak consistently. The amounts of methylene blue added to alkaline Ag colloid and time-evolution of Raman spectra were also investigated. Additionally, the alkaline silver colloid was prepared to be silver spot and applied to detect melamine doped milk. The relationship of the doping amount of melamine and the Raman signal intensity was obtained. The linearity relationship in the concentration range between 3 and 60 mg·L-1 with detect limit 0.28 mg·L-1 was achieved based on the intensity of 691 cm-1 Raman peak. This method required only 5 μL sample size and 5 s for detection and suggested that this presented method with its advantages of speediness, briefness and lower cost has a good application foreground..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 709 (2013)
Spectroscopic Study of Metal Coordination Compounds with 1,2-Trans-(4-Pyridyl)ethene
SHI Xiu-min, WANG Min, SONG Wei, and ZHAO Bing
In the present article, three kinds of metal-organic coordination compounds were synthesized between 1,2-trans-(4-pyridyl)ethene (dpe) and sulfate of Cu(Ⅱ), Zn(Ⅱ) and Cd(Ⅱ) by hydrothermal reactions. Infrared, Raman and ultraviolet-visible spectra of dpe and its metal-organic complexes were studied. Assignments of the In the present article, three kinds of metal-organic coordination compounds were synthesized between 1,2-trans-(4-pyridyl)ethene (dpe) and sulfate of Cu(Ⅱ), Zn(Ⅱ) and Cd(Ⅱ) by hydrothermal reactions. Infrared, Raman and ultraviolet-visible spectra of dpe and its metal-organic complexes were studied. Assignments of the main FTIR and Raman bands were done in detail. The relationship between these characteristic bands and the structure of ligands and coordination compounds was discussed. In the FTIR spectra, the co-vibration absorption band of C—C and C—N for dpe shifts to the higher wavenumbers for three metal-organic coordination compounds, respectively. In the Raman spectra, the corresponding vibration bands of C—N, CC, C—C and C—H were also observed to shift to higher wavenumbers. In the UV-visible absorption spectra, Zn-dpe and Cd-dpe has an absorption peak which could be attributed to the ligand absorption itself. However, two absorption peaks were observed for the complex of Cu-dpe, which were ascribed to the ligand absorption band and d—d electronic transition in the coordination compound. This indicates that there is a great change in the absorption spectra for the same ligand but with different metal ions..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 714 (2013)
Extraction of Bridge over Water from High-Resolution Remote Sensing Images Based on Spectral Characteristics of Ground Objects
CHEN Chao, QIN Qi-ming, CHEN Li, WANG Jin-liang, LIU Ming-chao, and WEN Qi
Bridge over water is a typical man-made target. Using the high-resolution optical remote sensing images, to extract bridge over water appears significant for civilian, military, and commerce. First, in the present paper, according to the spectral characteristics of water in near-infrared spectrum, water information is Bridge over water is a typical man-made target. Using the high-resolution optical remote sensing images, to extract bridge over water appears significant for civilian, military, and commerce. First, in the present paper, according to the spectral characteristics of water in near-infrared spectrum, water information is extracted using the iterative method for the threshold value, to limit the spatial extent of bridge extraction. Second, mathematical morphology is performed on the water information, to connect the separated water bodies due to the presence of bridges on the image. Third, overlay analysis is conducted between the two images before and after mathematical morphology operations, to extract the potential bridge. Finally, based on priori-knowledge of the bridge, the false bridge is removed. In this paper an experimental area is selected to verify the effectiveness and applicability of the method. Experimental results show that the method is effective for bridge extraction over water by using high-resolution remote sensing images based on spectral characteristics of ground objects..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 718 (2013)
Prediction of Total Nitrogen and Total Phosphorus Concentrations in Purple Soil Using Hyperspectral Data
XU Li-hua, XIE De-ti, WEI Chao-fu, and LI Bing
Hyper-spectral remote sensing is one of the effective means for prediction of soil nutrients. Taking Wangjiagou small watershed of Three Gorges Reservoir Area as researching zone, based on the soil physicochemical properties, reflective spectrum analysis and measurement, were built predictive models for total phosphoroHyper-spectral remote sensing is one of the effective means for prediction of soil nutrients. Taking Wangjiagou small watershed of Three Gorges Reservoir Area as researching zone, based on the soil physicochemical properties, reflective spectrum analysis and measurement, were built predictive models for total phosphorous and total phosphorus concentrations in purple soil. Meanwhile, 33 soil samples from paddy soil were used to validate the prediction models for soil nutrients in purple soil. Results show that the total correlation coefficients between their predicted values and measured values of total nitrogen and total phosphorus concentration in purple soil are 0.672 and 0.498, respectively. Correlation coefficients obtained from predictive model of purple soil nutrients validated by paddy soil samples are 0.550 and 0.124. Therefore, it is reasonable to use hyper-spectrum method to prediction total nitrogen concentration. But prediction accuracy for total phosphorus concentration in purple soil is relatively poor. The prediction model of soil nutrients in purple soil is not suitable for paddy soil..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 723 (2013)
Change Detection from High-Resolution Remote Sensing Image Based on MSE Model
WEI Li-fei, and WANG Hai-bo
At present, most of the traditional change detection methods from high-resolution remote sensing image are based on a feature information, the information of multi-feature information cannot be extracted, so it is difficult to detect the complete information. In order to solve this problem, a change detection algorithmAt present, most of the traditional change detection methods from high-resolution remote sensing image are based on a feature information, the information of multi-feature information cannot be extracted, so it is difficult to detect the complete information. In order to solve this problem, a change detection algorithm of high-resolution remote sensing image based on multiview spectral embedding is proposed in the present paper. Firstly, change image is obtained using traditional difference change detection method, and multi-feature information is extracted. The feature vector information is fused by a MSE model and the complete change information can be obtained. The experimental results show that the detection accuracy of the proposed method is better than the accuracy of traditional methods, and its stability is outstanding..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 728 (2013)
Early Diagnosis of Gray Mold on Tomato Stalks Based on Hyperspectral Data
KONG Wen-wen, YU Jia-jia, LIU Fei, HE Yong, and BAO Yi-dan
Early diagnosis of gray mold on tomato stalks based on hyperspectral data was studied in the present paper. A total of 112 samples’ hyperspectral data were collected by hyperspectral imaging system. The study spectral region was from 400 to 1 030 nm. Combined with image processing and chemometric methods, the tomato stEarly diagnosis of gray mold on tomato stalks based on hyperspectral data was studied in the present paper. A total of 112 samples’ hyperspectral data were collected by hyperspectral imaging system. The study spectral region was from 400 to 1 030 nm. Combined with image processing and chemometric methods, the tomato stalk gray mold diagnosis models were built. Seven effective wavelengths were selected by analysis of variable load distribution in PLS model. The experimental results showed that the excellent results were achieved by EW-LS-SVM model with standard normal variate (SNV) spectral and multiplicative scatter correction (MSC) spectral, and the accuracy of diagnosing gray mold on tomato stalks was satisfied and better than PLS model with whole band. Hence, it is feasible to early diagnose gray mold on tomato stalks using hyperspectral imaging technology, which provides a new early diagnosis and warning method for tomato disease..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 733 (2013)
Study on the Nonlinear Characteristics of the Mixed Pixel’s Reflectance in Hyperspectral Space
ZHU Feng, GONG Hui-li, SUN Tian-lin, and ZHAO Yun-sheng
Under the experimental condition of the 50 degree incidence zenith angle and 45 degree detection azimuth, 24 groups of reflectance spectral of the mixed pixel of lotus and water body acquired using the reflex platform and FieldSpec 3 Hi-Res portable spectrum instrument. The hyperspectral space was built based on the reUnder the experimental condition of the 50 degree incidence zenith angle and 45 degree detection azimuth, 24 groups of reflectance spectral of the mixed pixel of lotus and water body acquired using the reflex platform and FieldSpec 3 Hi-Res portable spectrum instrument. The hyperspectral space was built based on the reflectance character. The relationship between similarity and the index of lotus area ratio was analyzed using the linear, logarithm and quadratic curve fitting, and the goodness of fitting is 63.6%, 76.2% and 82.9% respectively. According to the real relationship of the mixed pixel spectral vector and the reference spectral, the best fitting model has nonlinear characteristics. The idea that the mixed pixel may have the critical value was proposed on the base of the analysis. The research result will help understand the mixed pixel further, and provide a new direction for unmixing the mixed pixel..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 737 (2013)
A Method of Object Detection for Remote Sensing Imagery Based on Spectral Space Transformation
WU Gui-ping, XIAO Peng-feng, FENG Xue-zhi, and WANG Ke
Object detection is an intermediate link for remote sensing image processing, which is an important guarantee of remote sensing application and services aspects. In view of the characteristics of remotely sensed imagery in frequency domain, a novel object detection algorithm based on spectral space transformation was pObject detection is an intermediate link for remote sensing image processing, which is an important guarantee of remote sensing application and services aspects. In view of the characteristics of remotely sensed imagery in frequency domain, a novel object detection algorithm based on spectral space transformation was proposed in the present paper. Firstly, the Fourier transformation method was applied to transform the image in spatial domain into frequency domain. Secondly, the wedge-shaped sample and overlay analysis methods for frequency energy were used to decompose signal into different frequency spectrum zones, and the center frequency values of object’s features were acquired as detection marks in frequency domain. Finally, object information was detected with the matched Gabor filters which have direction and frequency selectivity. The results indicate that the proposed algorithm here performs better and it has good detection capability in specific direction as well..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 741 (2013)
Hyperspectral Remote Sensing Image Classification Based on SVM Optimized by Clonal Selection
LIU Qing-jie, JING Lin-hai, WANG Meng-fei, and LIN Qi-zhong
Model selection for support vector machine (SVM) involving kernel and the margin parameter values selection is usually time-consuming, impacts training efficiency of SVM model and final classification accuracies of SVM hyperspectral remote sensing image classifier greatly. Firstly, based on combinatorial optimization tModel selection for support vector machine (SVM) involving kernel and the margin parameter values selection is usually time-consuming, impacts training efficiency of SVM model and final classification accuracies of SVM hyperspectral remote sensing image classifier greatly. Firstly, based on combinatorial optimization theory and cross-validation method, artificial immune clonal selection algorithm is introduced to the optimal selection of SVM (CSSVM) kernel parameter σ and margin parameter C to improve the training efficiency of SVM model. Then an experiment of classifying AVIRIS in India Pine site of USA was performed for testing the novel CSSVM, as well as a traditional SVM classifier with general Grid Searching cross-validation method (GSSVM) for comparison. And then, evaluation indexes including SVM model training time, classification overall accuracy (OA) and Kappa index of both CSSVM and GSSVM were all analyzed quantitatively. It is demonstrated that OA of CSSVM on test samples and whole image are 85.1% and 81.58, the differences from that of GSSVM are both within 0.08% respectively; And Kappa indexes reach 0.821 3 and 0.772 8, the differences from that of GSSVM are both within 0.001; While the ratio of model training time of CSSVM and GSSVM is between 1/6 and 1/10. Therefore, CSSVM is fast and accurate algorithm for hyperspectral image classification and is superior to GSSVM..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 746 (2013)
Research on Detecting Concentration of Serum Protein Based on Resonance Rayleigh Scattering
WANG Gao, FENG Qiao-ling, XUE Zhong-jin, LI Yang-jun, and ZHOU Han-chang
The resonance Rayleigh scattering spectral detection system was designed based on the 2,9,16,23-tetracarboxylate-phthalocyanine zinc and protein system. In the system, excitation light source is 405 nm wide band gap semiconductor lasers, and monochromator is 475 nm narrow-band band-pass filter, and the detector is low-The resonance Rayleigh scattering spectral detection system was designed based on the 2,9,16,23-tetracarboxylate-phthalocyanine zinc and protein system. In the system, excitation light source is 405 nm wide band gap semiconductor lasers, and monochromator is 475 nm narrow-band band-pass filter, and the detector is low-noise and high-gain photoelectric amplifier based on blue-ray enhanced photodiode. Experiment shows that, the solution’s strong absorption wavelength is near 420 nm. Under the action of incentive light, resonance Rayleigh scattering is generated at the resonant wavelength, and the scattering intensity is proportional to the protein content. The system uses 2,9,16,23-tetracarboxylate as the spectrum probe to determine the concentration of serum proteins by resonance Rayleigh scattering method. Its linear detection range is 10 ~ 50 mg·mL-1, and its detection limit is 0.001 mg·mL-1. The newly developed device for detecting concentration of the serum protein has the advantages of small size, low cost, low power consumption, and being easy to use..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 752 (2013)
Research on Serum Prostate-Specific Antigen Measurement by Characteristic Spectral Imaging Method
ZHU Jian-ming, and CHEN Zhen-cheng
A serum prostate-specific antigen (PSA) measurement method was studied using characteristic spectral imaging method and immunochromatography-based colloidal gold-marked test-strips. An annular light source made of LEDs in the range from 520 to 535 nm irradiated the test-strips sampled by PSA in darkroom, and then the pA serum prostate-specific antigen (PSA) measurement method was studied using characteristic spectral imaging method and immunochromatography-based colloidal gold-marked test-strips. An annular light source made of LEDs in the range from 520 to 535 nm irradiated the test-strips sampled by PSA in darkroom, and then the photograph of the test-strip was captured by the CCD industrial camera and transferred to PC. The characteristic value of the test line on the test-strip was acquired by the Quantitative Testing Software on PC using grey level transformation and image segmentation, and then the relationship between the characteristic value and PSA level could be ascertained by cubic polynomial fitting method. Some experiments were completed by 25 blood samples which were taken from one man with no prostate disease and 24 men with prostate disease, and then the correlation coefficient between the measurement values and the true values equals to 0.924. In addition, when the PSA level in the blood sample is lower than 25 ng·mL-1, the measurement accuracy is higher than that when the PSA level in the blood sample exceeds 25 ng·mL-1. The experimental results proved that the proposed method for serum PSA level measurement is feasible..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 762 (2013)
Study on Relationship Between Alfalfa Canopy Spectral Reflectance and Leaf Water Content
FU Yan-bo, FAN Yan-min, SHENG Jian-dong, LI Ning, WU Hong-qi, LI Mei-ting, LI Li, and ZHAO Yun
In the present study, alfalfa canopy reflectance was researched at alfalfa squaring period under different irrigation amount at the hutubi county grassland ecological station. Determining the spectral diagnostic model of alfalfa leaf moisture content was determined by spectrometry. The results showed that (1) The spectIn the present study, alfalfa canopy reflectance was researched at alfalfa squaring period under different irrigation amount at the hutubi county grassland ecological station. Determining the spectral diagnostic model of alfalfa leaf moisture content was determined by spectrometry. The results showed that (1) The spectral reflectance of alfalfa canopy gradually decreases with the increase in the leaf water content in the near infrared. (2) The spectral inversion model of alfalfa leaf moisture content established by normalized reflectance spectra is superior to the original reflectance spectra, and the prediction model established in the 1 344~1 660 nm band has the lowest average relative error (7.8%). (3) In this study, the spectral diagnostic model of the leaf moisture content is: Y＝0.962-7.560X1 451+5.295X1 473. The spectral prediction model of the alfalfa leaf moisture content can provide a basis for decision making for scientific irrigation of alfalfa..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 766 (2013)
Spectra Characteristic Effect of Different Density-Resistant Maize Variety on Planting Density
TANG Li-yuan, MA Wei, LI Lian-lu, and ZHAO Ming
With Chlorophyll Meter SPAD-502 and Canopy Analyzer AccuPAR LP-80, the spectra characteristic effect of different density-resistant maize variety on planting density was studied, and the effect of planting density on photosynthetic performance of maize was discussed. The materials of the experiment were Yinong-103, XiaWith Chlorophyll Meter SPAD-502 and Canopy Analyzer AccuPAR LP-80, the spectra characteristic effect of different density-resistant maize variety on planting density was studied, and the effect of planting density on photosynthetic performance of maize was discussed. The materials of the experiment were Yinong-103, Xianyu-335, Zhengdan-958 and Denghai-661, the row spacing was 80 cm×40 cm, the plant spacing was gradually changed from 1m to smaller spacing, the densities were 3.33, 3.70, 4.17, 4.50, 4.76, 5.56, 6.67, 6.80, 8.33, 9.00, 11.11, 11.20 and 16.67 planting·m-2 respectively. We studied spectra characteristic effect on planting density, and investigated maize photosynthetic characteristics and density-yield relationship to get high yield. This research can be good case of using maize spectra characteristic to reflect plant photosynthetic characteristics and canopy architecture. The end of this paper was to explore density effect on yield with spectroscopy means..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 770 (2013)
Effects of Temperature on the Ultraviolet Absorption Characteristics of SO2
ZHENG Hai-ming, and JIN Wei-jia
Absorption spectrum of SO2 is obtained under the condition of room temperature and atmosphere pressure. The spectrum is composed of banded structure superimposed on a continuum. The continuum structure comes from the transition of SO2 molecule from the ground electronic state to the higher dense rovibronic energy levelAbsorption spectrum of SO2 is obtained under the condition of room temperature and atmosphere pressure. The spectrum is composed of banded structure superimposed on a continuum. The continuum structure comes from the transition of SO2 molecule from the ground electronic state to the higher dense rovibronic energy levels, and the banded one comes from the transition of B1B1←X1A1. The symmetric stretch and bend vibration frequencies are obtained from the banded structure. They are ω1=(665±29) cm－1 and ω2=(448±17) cm－1, respectively. Measuring the absorption spectra of SO2 at different temperature, it was also found that the configuration of the spectra is similar. But the absorption cross-section decreases with the increase in temperature. The absorption cross-section corresponding to the absorption peaks varies with temperature in the manner of cube. But the rate coefficients are different. So the effect of temperature on the measurement results must be considered when we use the technique of DOAS for the detection of SO2..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 776 (2013)
A Dimension Reduction Method Applied in Spectrum Analysis
LI Qing-bo, and JIA Zhao-hui
It is the premise of establishing stable and accurate model to extract useful information from spectrum data in Vis/NIR spectrum analysis technology. ISOMAP is a dimension reduction method, and can effectively extract the intrinsic low dimension from high dimensional data, but is sensitive to noise and neighborhood parIt is the premise of establishing stable and accurate model to extract useful information from spectrum data in Vis/NIR spectrum analysis technology. ISOMAP is a dimension reduction method, and can effectively extract the intrinsic low dimension from high dimensional data, but is sensitive to noise and neighborhood parameter. In this paper, an improved ISOMAP algorithm, called supervised dimension reduction, is proposed. It guides the construction of the neighborhood graph using correlation owned by spectrum data, and reduces sensitivity to noise and neighborhood parameter. The algorithm was applied to two datasets, and then PLS models were established. The experiment results indicated that the improved algorithm was less sensitive to the neighborhood size and more robust and more topologically stable. In addition, smaller dimension was extracted, and the model precision was improved at the same time..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 780 (2013)
Determination of Potassium in Farmland Soil Using Laser-Induced Breakdown Spectroscopy
DONG Da-ming, ZHENG Wen-gang, ZHAO Chun-jiang, ZHAO Xian-de, JIAO Lei-zi, and ZHANG Shi-rui
The real-time measurement of potassium in farmland soil has great importance. A method to determine the potassium content in farmland soil based on laser-induced breakdown spectroscopy (LIBS) was studied using a LIBS equipment consisting of a 1 064 nm laser generator and a high resolution spectrometer. The farmland soiThe real-time measurement of potassium in farmland soil has great importance. A method to determine the potassium content in farmland soil based on laser-induced breakdown spectroscopy (LIBS) was studied using a LIBS equipment consisting of a 1 064 nm laser generator and a high resolution spectrometer. The farmland soil samples with potassium content in the range of 8.74~34.56 g·kg-1 were analyzed. The 766.49 nm was chosen as the analysis line, by comparing the potassium atom characteristic lines of 404.40, 404.72, 766.49 and 769.90 nm. The errors of characteristic line strength caused by the laser stability and random noise was analyzed. The silicon, which is nearly constant in farmland soil, was chosen as the standard element, and a calibration model between the ratio of potassium to silicon (K/Si) and the potassium content was established. The linear fitting degree of the calibration curve was 0.935, and the relative standard deviation of the calibration model for prediction set samples was 9.26%..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 785 (2013)
Emission Spectroscopic Study on Radicals Generated in Liquid-Phase Diaphragm Glow Discharge Plasma
LIU Yong-jun, SUN Bing, and WANG Lei
In order to probe the aqueous reaction mechanism of liquid-phase diaphragm glow discharge (LDGD), radicals formed during the discharge were analyzed by their emission spectra. Emissions of H atoms and OH radicals were observed when the applied voltage was above 700 V. When the applied voltage increased to 750 V, emissiIn order to probe the aqueous reaction mechanism of liquid-phase diaphragm glow discharge (LDGD), radicals formed during the discharge were analyzed by their emission spectra. Emissions of H atoms and OH radicals were observed when the applied voltage was above 700 V. When the applied voltage increased to 750 V, emissions of O atoms were additionally detected. The emission intensities of these radicals and atoms increased with increasing applied voltage. The average electron temperature and the mean electron density of the LDGD plasma were 1.3×104 K and 7.8×1017 cm-3, respectively..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 790 (2013)
Experimental Study on Spectra of Compressed Air Microwave Plasma
LIU Yong-xi, ZHANG Gui-xin, WANG Qiang, and HOU Ling-yun
Using a microwave plasma generator, compressed air microwave plasma was excited under 1～5 atm pressures. Under different pressures and different incident microwave power, the emission spectra of compressed air microwave plasma were studied with a spectra measuring system. The results show that continuum is significant Using a microwave plasma generator, compressed air microwave plasma was excited under 1～5 atm pressures. Under different pressures and different incident microwave power, the emission spectra of compressed air microwave plasma were studied with a spectra measuring system. The results show that continuum is significant at atmospheric pressure and the characteristic will be weakened as the pressure increases. The band spectra intensity will be reduced with the falling of the incident microwave power and the band spectra were still significant. The experimental results are valuable to studying the characteristics of compressed air microwave plasma and the generating conditions of NO active groups..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 794 (2013)
Study on Speciation and Fractionation of Rare Earth Elements in Surface Sediments in Gansu, Ningxia and Inner Mongolia Sections of Yellow River
LIU Jing-jun, LAI Zi-juan, and LIU Ying
In the present paper, BCR sequential extraction and high resolution inductively coupled plasma-mass spectrometry (HR-ICP-MS) were performed to analyze the speciation contents of 14 kinds of rare earth elements (REE) in the surface sediments from 12 sampling sites (S1-S12) in Gansu, Ningxia and Inner Mongolia Sections oIn the present paper, BCR sequential extraction and high resolution inductively coupled plasma-mass spectrometry (HR-ICP-MS) were performed to analyze the speciation contents of 14 kinds of rare earth elements (REE) in the surface sediments from 12 sampling sites (S1-S12) in Gansu, Ningxia and Inner Mongolia Sections of Yellow River, and REE fractionation were also studied. The results indicated that the contents of REE in 12 sediment samples were the same order. The average contents of 14 rare earth elements were in this order: Ce(66.4)>La(35.8)>Nd(28.6)>Pr(7.88)>Sm(5.87) >Gd(5.01)>Dy(4.53)>Yb(2.86)>Er(2.51)>Eu(1.31)>Ho(0.856)>Tb(0.760)>Tm(0.428)>Lu(0.404), which were similar to the Chinese soil background. The residual fractions of all elements were present at the highest percentages(71.9%～93.9%), which indicated that the bioavailability or environmental impact was low. The percentage of reducible fraction was the lowest, ranged from 0.20% to 3.87% with the mean value of 0.83%, while the oxidizable fraction percentage(7.61%) was close to acid-soluble fraction(7.69%). But in Maqu (S12), oxidizable percentage (16.1%) was significantly higher than the acid-soluble fraction(1.73%). Correlation analysis showed that there was a significant positive correlation between total organic carbon (TOC) content and oxidizable percentage, and the correlation coefficients were between 0.763 and 0.914. REE fractionation results showed that: the contents of REE in surface sediments of Gansu, Ningxia and Inner Mongolia Sections of Yellow River were mainly from soil weathering, with light-REE enrichment and Eu depletion. The chondrite-normalized curve implied that La and Ce in Jinshawan (S8) and Baotou-Dengkou (S1) and heavy REE at all the sampling points might have external REE sources..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 798 (2013)
Dynamic Analysis of Mineral Elements During Growth and Development Stage of the Kirilowii Plant
MA Zhao, WEI Min, CUI Xu-sheng, and GUO Yu-hai
ICP-AES technology was used to determine the major mineral elements content and analyze the dynamic and cumulative amount of the main absorption during the growth and development stage of the Kinlowii organs plant.The result showed as follows: (1)The mineral elements were changing in the different stage. The highest miICP-AES technology was used to determine the major mineral elements content and analyze the dynamic and cumulative amount of the main absorption during the growth and development stage of the Kinlowii organs plant.The result showed as follows: (1)The mineral elements were changing in the different stage. The highest mineral element accumulation of K, P, Ca, Mg, Fe, Mn, Zn, Cu and Mo occured in October, their values are 3 695.90, 445.88, 9 649.32, 2 652.10 mg per plant, 324 398.29, 40 188.65, 22 383.13, 36 054.58 and 61.95 μg per plant separately. But the highest value of B occured in September and the value was 8 690.97 μg per plant. (2) the distribution of mineral element in the kirilowii plant was not even, the contents of K and P were highest in kirilowii peel, they can reach 27.65 and 2.63 mg·g-1. The contents of Ca and Mg were highest in kirilowii leaves, they can reach 33.28 and 5.73 mg·g-1. The contents of Fe, Mn, B were highest in kirilowii roots, they can reach: 4 069.74, 127.73, 24.75 μg·g-1.The contents of Zn and Mo were highest in kirilowii seeds, they can reach 68.61 and 1.07 μg·g-1. (3) the cumulation dynamic of mineral elements in kirilowii plant during the whole stages was S-type, and the plant showed rapid growth from the mid-July to mid-Spetember. The information of this study will supply a scientific data for the quality assessment and rational fertilization of kirilowii plant and harvestment..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 804 (2013)
Evaluation and Analysis of Inorganic Elements in Ginkgo Biloba Leaves by Microwave Digestion-ICP-AES
YAO Xin, ZHOU Gui-sheng, TANG Yu-ping, SHANG Er-xin, SU Shu-lan, QIAN Da-wei, and DUAN Jin-ao
Inorganic elements were determined by ICP-AES using microwave digestion, and principal components analysis(PCA) was used for analysis. The result showed that ginkgo biloba leaves contained more than 22 inorganic elements, Fe, Zn, Cu, Mn, Cr, Co, Ni, Sr, B, Si and Ni were essential trace elements, and Ca, P, K, Na and MInorganic elements were determined by ICP-AES using microwave digestion, and principal components analysis(PCA) was used for analysis. The result showed that ginkgo biloba leaves contained more than 22 inorganic elements, Fe, Zn, Cu, Mn, Cr, Co, Ni, Sr, B, Si and Ni were essential trace elements, and Ca, P, K, Na and Mg were essential macro elements. PCA with seven factors (F1, F2, F3, F4, F5, F6, F7) selected could be used to evaluate the quality of ginkgo biloba leaves. The function was following F=0.230 17F1+0.122 39F2+0.079 67F3+0.078 97F4+0.065 25F5+0.062 03F6+0.056 71F7. The samples from Taixing, Shijiazhuang and Taian was the top three which indicated the quality in those cultivation sources was better based on inorganic elements. All the results will provide good basis for comprehensive utilization of ginkgo biloba leaves, especially the leaves from fruit cultivars..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 808 (2013)
Determination of Mineral Elements in Cistanche and Its Extractives by ICP-AES
ZHU Yan-xia, and GUO Yu-hai
Determination of Fe, Zn, Cu, K, P, Ca, Mg, Na, B and Al in cistanche and its extractives was carried out by the inductively coupled plasma atomic emission spectrometry (ICP-AES). The results showed that (1) the contents of Mn, K, Ca, Mg and Na in cistanche deserticola Y. C. Ma were 17.70, 16 278.03, 1 947.25, 1 662.76,Determination of Fe, Zn, Cu, K, P, Ca, Mg, Na, B and Al in cistanche and its extractives was carried out by the inductively coupled plasma atomic emission spectrometry (ICP-AES). The results showed that (1) the contents of Mn, K, Ca, Mg and Na in cistanche deserticola Y. C. Ma were 17.70, 16 278.03, 1 947.25, 1 662.76, and 106.79 respectively (μg·g-1), much higher than in Cistanche tubulosa (Schrenk) Wight; (2) the contents of Fe, Cu and P in 50% methanol extract of Cistanche deserticola were 1.5, 2.4, and 1.1 times that of aqueous extract respectively, the contents of Mn, Zn, K, P, Mg and Na were 3.8, 1.2, 1.6, 2.3, 2.2, and 1.1 times that of methanol extract respectively; (3) the contents of Cu and P in 50% methanol extract of Cistanche tubulosa were 1.6 and 1.2 times that of aqueous extract, the contents of Mn, Zn, K, P, Mg, Na and Al were 2.0, 1.6, 1.6, 1.4, 1.8, 1.2, and 1.2 times that of methanol extract respectively; (4) the leaching rate of 11 mineral elements in Cistanche deserticola and Cistanche tubulosa were 60.79%~83.10% and 44.58%~83.84% in 50% methanol respectively, and the leaching rate of Mn, Zn, K, P, Ca, Na and Al were much higher than in water and 100% methanol extracted. The research provided the basic data of mineral element in comparative study on Cistanche deserticola and Cistanche tubulosa, and provide scientific basis for efficient utilization of mineral element in cistanche..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 813 (2013)
Study of Adsorption and Desorption of Behaviors of Pb2+ on Thiol-Modified Bentonite by Flame Atomic Absorption Spectrometry
CHEN Wen, XIONG Qiong-xian, PANG Xiao-feng, ZHU Xia-ping, HAN Mei, ZHAO Qiu-xiang, and LIU Wen-hua
A comparative analysis of the functional groups and surface structure of the Ca-bentonite (RB) and thiol-modified bentonite (TMB) were characterized by means of FTIR and SEM. The absorptive property of Pb2+ on TMB and RB and its influential factors was studied and the conditions for the adsorption were optimized by usiA comparative analysis of the functional groups and surface structure of the Ca-bentonite (RB) and thiol-modified bentonite (TMB) were characterized by means of FTIR and SEM. The absorptive property of Pb2+ on TMB and RB and its influential factors was studied and the conditions for the adsorption were optimized by using FAAS method. Then the conditions for desorption of Pb2+ from the TMB by using simulated acid rain were studied and the contrast analysis of absorptive stability of Pb2+ on TMB and RB was given. The results showed that the adsorption rate of Pb2+ by TMB could reach more than 98%, when the initial Pb2+ concentration was 100 mg·L-1, the liquid-solid ratio was 5 g·L-1, pH was 6.0, KNO3 ionic strength was 0.1 mol·L-1 and adsorption period was 60min at 25 ℃. The saturated adsorption capacity of TMB was 67.27 mg·g-1; it’s much more than that of RB (9.667 mg·g-1). The adsorption of Pb2+ on TMB follows Langmuir and Freundlich isotherm models well. Desorption experiments of Pb2+ from TMB with simulated acid rain (pH 3.50) were done, and the desorption rate was 0. The results showed that TMB has a strong adsorption and fixation capacity for Pb2+; it is adapted to lead contaminated soil for chemical remediation..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 817 (2013)
Preconcentration of Ultra-Trace As(Ⅲ) in Water Samples with Nano-Sized ZnO and Determination by HGAFS with Colloid Sampling
PENG Hong, and ZHANG Xu
When the pH values of solution were 6.5～7.5, the adsorption efficiency of nano-sized ZnO for As(Ⅲ) was higher than 99.5% in 10 min shaking. Based on the high adsorption capacity of As(Ⅲ) onto nano-sized ZnO and the good solubility of ZnO in acidic solution, a novel method for preconcentration of ultra-trace As(Ⅲ) by usWhen the pH values of solution were 6.5～7.5, the adsorption efficiency of nano-sized ZnO for As(Ⅲ) was higher than 99.5% in 10 min shaking. Based on the high adsorption capacity of As(Ⅲ) onto nano-sized ZnO and the good solubility of ZnO in acidic solution, a novel method for preconcentration of ultra-trace As(Ⅲ) by using ZnO was presented in the present work. After preconcentration and centrifugation, the supernatant fluid was removed. The sediment which contained the concentrated As(Ⅲ) was dissolved in HCl solution and the concentration was analyzed by hydride generation atomic fluorescence spectrometry (HGAFS). The proposed method possesses low detection limit (3σ) (0.075 μg·L-1) and good precision (the relative standard deviation (RSD) is 1.6%, n=6). The recovery rate for the analyzing of aquatic samples is between 97.0% and 104.5%. The results show that the method is simple, time saving and high sensitive..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 822 (2013)
Determinatoin of Trace Mercury in Sludge Samples by Hydride Generation-Atomic Fluorescence Spectrometry
WANG Yan-yan, SHI Zhi-qiang, and ZHANG Biao
Due to the complex matrix characteristic of sludge samples, the research on three wet digestion systems and the conditions of reducing agent, and carrier flow was carried. The experiment conditions of HNO3-HClO4 wet systems, namely 5% HNO3 carrier flow, 0.1% NaBH4 reducing agent, and acidity medium of 5% HNO3+0.05% K2CDue to the complex matrix characteristic of sludge samples, the research on three wet digestion systems and the conditions of reducing agent, and carrier flow was carried. The experiment conditions of HNO3-HClO4 wet systems, namely 5% HNO3 carrier flow, 0.1% NaBH4 reducing agent, and acidity medium of 5% HNO3+0.05% K2Cr2O7 mixed solution, etc. were finally determined to measure the trace mercury in sludge samples. This recommended method has many advantages, such as accurate and quick detection and simple operation. The determination limit is 0.06 μg·L-1, and the relative standard deviation for 11-time determination of the solution containing 4.0 μg·L-1 Hg is 2.0%. This method for trace mercury in sludge samples by hydride generation-fluorescence (HG-AFS) can be widely used..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 826 (2013)
Investigation of Characteristic Microstructures of Adhesive Interface in Wood/Bamboo Composite Material by Synchrotron Radiation X-Ray Phase Contrast Microscopy
PENG Guan-yun, WANG Yu-rong, REN Hai-qing, YANG Shu-min, MA Hong-xia, XIE Hong-lan, DENG Biao1, DU Guo-hao1, and XIAO Ti-qiao
Third-generation synchrotron radiation X-ray phase-contrast microscopy（XPCM）can be used for obtaining image with edge enhancement, and achieve the high contrast imaging of low-Z materials with the spatial coherence peculiarity of X-rays. In the present paper, the characteristic microstructures of adhesive at the interfThird-generation synchrotron radiation X-ray phase-contrast microscopy（XPCM）can be used for obtaining image with edge enhancement, and achieve the high contrast imaging of low-Z materials with the spatial coherence peculiarity of X-rays. In the present paper, the characteristic microstructures of adhesive at the interface and their penetration in wood/bamboo composite material were investigated systematically by XPCM at Shanghai Synchrotron Radiation Facility (SSRF). And the effect of several processing techniques was analyzed for the adhesive penetration in wood/bamboo materials. The results show that the synchrotron radiation XPCM is expected to be one of the important precision detection methods for wood-based panels..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 829 (2013)
XPS and UPS Characterization for Cr and Mn in High-Temperature Oxide Films of Bulk Nanocrystalline 304 Stainless Steel
XU Song-ning, WANG Sheng-gang, HAN Hai-bao, and SUN Nai-kun
The authors studied the binding energies of valence electrons of two oxide scales, the atomic percentages of Cr and Mn elements in two oxide films, the work function of two oxide films on bulk nanocrystalline 304 stainless steel (BN-SS304) and conventional polycrystalline 304 stainless steel (CP-SS304). BN-SS304 was prThe authors studied the binding energies of valence electrons of two oxide scales, the atomic percentages of Cr and Mn elements in two oxide films, the work function of two oxide films on bulk nanocrystalline 304 stainless steel (BN-SS304) and conventional polycrystalline 304 stainless steel (CP-SS304). BN-SS304 was prepared by severe rolling technique, and the two oxide films were formed in atmosphere at 900 ℃ for 24 hours oxidation on BN-SS304 and CP-SS304 surfaces. In the two oxide films, Cr and Mn elements exist in the forms of Cr3+, Cr0, Mn4+ and Mn0. The atomic percentage ratios of Cr3+ / (Cr3+ +Cr0) and Mn4+/ (Mn4++Mn0) in the oxide film on BN-SS304 are lower than those in the oxide film on CP-SS304. The interactions of the two oxides and the valence electrons of elements are Mn—O, Cr—O, 3d and 4s of Mn0 and Cr0. The binding energies of the valence electrons in the oxide film on BN-SS304 are larger than those in the oxide film on CP-SS304, the work function of the oxide film on BN-SS304 is 0.07 eV larger than that on CP-SS304..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 834 (2013)
Design of the Airborne Prism Dispersive Imaging Spectrometer System Based on Offner Relay Configuration
FANG Yu, XIANGLI Bin, YUAN Yan, L Qun-bo, and ZHOU Jin-song
Considering the development of the need for small volume and light weight of spectral imaging systems on airborne platform, the characters of several main imaging spectrometers was analyzed and the present paper focuses on introducing imaging spectrometers featuring a grating or a prism disperser .A compact hyperspectrConsidering the development of the need for small volume and light weight of spectral imaging systems on airborne platform, the characters of several main imaging spectrometers was analyzed and the present paper focuses on introducing imaging spectrometers featuring a grating or a prism disperser .A compact hyperspectral imaging system based on Offner relay configuration is reported. Combining the characters of the concentric Offner relay, and knowing the system design parameters, two novel kinds of spherical spectrometer systems using dispersive elements in divergent and convergent beam were designed. Moreover, the system MTF, spot diagram and the curves of smile and keystone were analyzed. The results show that these two kinds of Offner spectrometer achieve the purpose of a compact form of remote sensing system with excellent imaging quality close to diffraction limit. At the same time, decreasing the smile and keystone to a small (0.1) fraction of a pixel assures uniformity of acquiring spectral data..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 838 (2013)
Study on Transmission Efficiency of Interference System in Spatially Modulated Fourier Transform Spectrometer
L Jin-guang, LIANG Jing-qiu, LIANG Zhong-zhu, QIN Yu-xin, and TIAN Chao
The reflection of the optic system surface and the absorption of the infrared material could reduce the transmission of the incident light in spatially modulated Fourier transform infrared spectrometer. Through the calculation of the transmission function of the interference system and the simulation of the interferogrThe reflection of the optic system surface and the absorption of the infrared material could reduce the transmission of the incident light in spatially modulated Fourier transform infrared spectrometer. Through the calculation of the transmission function of the interference system and the simulation of the interferogram image and recovered spectrum affected by transmission function, it was indicated that the contrast of the interferogram image declined and the spectral line intensity weakened. The theoretical analysis shows that the contrast of the interferogram image was related to the intensity reflectance of the anti-reflection film, and the attenuation of the spectrum was determined by transmission efficiency concerned with intensity reflectance R1 of the anti-reflection film, intensity reflectance R2 of the beam splitter film, and the absorption coefficient. By means of the analysis and argumentation, the absorption of the material could be ignored in our investigative wave band. So the transmission efficiency was determined only by R1 and R2. Then taking the transmission efficiency as the design target, according to the transmission required by system, the tolerance of the R1 and R2 could be gained..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 850 (2013)
The Meteorological Satellite Spectral Image Registration Based on Fourier-Mellin Transform
WANG Liang, LIU Rong, ZHANG Li, DUAN Fu-qing, and L Ke
The meteorological satellite spectral image is an effective tool for researches on meteorological science and environmental remote sensing science. Image registration is the basis for the application of the meteorological satellite spectral image data. In order to realize the registration of the satellite image and theThe meteorological satellite spectral image is an effective tool for researches on meteorological science and environmental remote sensing science. Image registration is the basis for the application of the meteorological satellite spectral image data. In order to realize the registration of the satellite image and the template image, a new registration method based on the Fourier-Mellin transform is presented in this paper. Firstly, we use the global coastline vector map data to build a landmark template, which is a reference for the meteorological satellite spectral image registration. Secondly, we choose infrared sub-image of no cloud according to the cloud channel data, and extract the edges of the infrared image by Sobel operator. Finally, the affine transform model parameters between the landmark template and the satellite image are determined by the Fourier-Mellin transform, and thus the registration is realized. The proposed method is based on the curve matching in essence. It needs no feature point extraction, and can greatly simplify the process of registration. The experimental results using the infrared spectral data of the FY-2D meteorological satellite show that the method is robust and can reach a high speed and high accuracy..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 855 (2013)
A Novel Infrared Chemosensor for Recognition of Fluoride and Acetate Anions
SUN Jin-yu, TIAN Xiao-hui, GU Yun, YUAN Yi-zhong, and WANG Jun
A novel organometallic chromophore with potential infrared (IR) chemical sensing property, named as N’-(2-pyridinyl)-N-phenylurea tricarbonyl chromium, was synthesized and systematically characterized by nuclear magnetic resonance (NMR), mass spectra (MS) and elemental analysis. The recognition and IR sensing behavior A novel organometallic chromophore with potential infrared (IR) chemical sensing property, named as N’-(2-pyridinyl)-N-phenylurea tricarbonyl chromium, was synthesized and systematically characterized by nuclear magnetic resonance (NMR), mass spectra (MS) and elemental analysis. The recognition and IR sensing behavior toward fluoride and acetate anions was investigated in chloroform. The results of IR titration indicated that, when the concentration of the two anions was greater than 10-5 mol·L-1, a good linear relationship between the stretching vibration of metal carbonyl of N’-(2-pyridinyl)-N-phenylurea tricarbonyl chromium and the concentration of the two anions was observed, which exhibits expected application in trace analysis of fluoride and acetate with detection error less than 5%..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 859 (2013)
[in Chinese]
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 1 (2013)
A Compression Algorithm for Multi-Spectral TDICCD Image
LIU Yan-yan, GAO Yin-han, LI Jin, JIN Long-xu, HAN Shuang-li, and LI Guo-ning
In order to solve the problem of edge and texture blurring of multi-spectral image caused by the wavelet transform and bit-plane encoder of traditional method not taking into account image characteristics, a compression algorithm of multi-spectral TDICCD image having few bands is proposed in the present paper. The propIn order to solve the problem of edge and texture blurring of multi-spectral image caused by the wavelet transform and bit-plane encoder of traditional method not taking into account image characteristics, a compression algorithm of multi-spectral TDICCD image having few bands is proposed in the present paper. The proposed direction-adaptive lifting DWT can adaptively choose the best lifting direction and use the Lagrange interpolation technique to make prediction according to its local characteristics. This method makes good use of the image texture features. The proposed rate control algorithm can adaptively allocate the rate bits according to image content. The experiments results showed that the proposed compression algorithm has good compressive property. Compared with traditional approaches, the performance of our method corresponds to the conventional approach for smooth images. However, it was superior to others for images with rich texture and a large number of edge detail information. In the compression ration 4∶1, the average peak signal to noise ratio of the proposed compression algorithm could improve the average PSNR by 1.939 dB. They effectively protect the edge and texture detail information for multi-spectral image. It is very suitable for the application of space multi-spectral CCD image with rich texture and a large number of edge detail information..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 844 (2013)
Research Articles
Evaluating the Utility of MODIS Vegetation Index for Monitoring Agricultural Drought
LI Hua-peng, ZHANG Shu-qing, GAO Zi-qiang, and SUN Yan
The exclusive shortwave bands provided by MODIS sensors offer new opportunities for agricultural drought monitoring, since they are very sensitive to vegetation moisture. In the present work, we selected Songnen Plain in Northeast China as study area aiming at monitoring agricultural drought of dry farmland here. Four The exclusive shortwave bands provided by MODIS sensors offer new opportunities for agricultural drought monitoring, since they are very sensitive to vegetation moisture. In the present work, we selected Songnen Plain in Northeast China as study area aiming at monitoring agricultural drought of dry farmland here. Four types of vegetation water indices and vegetation greenness indices were calculated from the 8-day composite MODIS product (MOD09A1) in vegetation growing season between 2001 and 2010, respectively. Multi-scale standardized precipitation index (SPI) derived from precipitation data of weather stations was used as reference data to estimate drought sensitivity of various vegetation indices, and a pixel-to-weather station paired correlation approach was used to calculate the Pearson correlation coefficient between vegetation index and SPIs. The result indicated that vegetation water indices established by near infrared and shortwave infrared bands outperformed vegetation greenness indices based on visible and near infrared bands. Of these indices, NDII7 performs the best with highest correlation coefficients across all SPIs. The authors’ results demonstrated the potential of MODIS shortwave spectral bands in monitoring agricultural drought, and this provides new insights to future research..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 3, 756 (2013)
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