Journals >Spectroscopy and Spectral Analysis
Contents
2011
Volume: 31 Issue 8
62 Article(s)
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Research Article
Surface Plasmon Resonance Sensor Working at Terahertz Frequency
FENG Hui, and WANG Li
The authors provided an analysis of the surface plasmon resonance sensor (SPRS) working at terahertz (THz) frequency with angular modulation and made a brief comparison between optical SPRS and THz-SPRS. At optical frequency, there is a dip in the angular reflection spectrum due to the resonant transfer of the energy cThe authors provided an analysis of the surface plasmon resonance sensor (SPRS) working at terahertz (THz) frequency with angular modulation and made a brief comparison between optical SPRS and THz-SPRS. At optical frequency, there is a dip in the angular reflection spectrum due to the resonant transfer of the energy carried by the incident light wave to surface plasmon, while there is an enhanced reflection peak at the terahertz frequency. The position of the peak is solely determined by the refractive indices of the prism and the sample, and independent of the properties of the metal film. Our results show that the determination of the dielectric constant of a sample in the THz SPRS is much simpler than its optical counterpart. Taking into account of the importance of THz technology applying in biological and medical field, tThe authors’ device may provide a valuable method for bio-sensing and analysis..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2017 (2011)
Advance on Application of Hyperspectral Imaging to Nondestructive Detection of Agricultural Products External Quality
LI Jiang-bo, RAO Xiu-qin, and YING Yi-bin
Hyperspectral imaging is an emerging technique that integrates conventional imaging and spectroscopy to obtain both spatial and spectral information from a studied object simultaneously. The images data can reflect the external features, surface defects and contamination. The spectra data can analyze physical structureHyperspectral imaging is an emerging technique that integrates conventional imaging and spectroscopy to obtain both spatial and spectral information from a studied object simultaneously. The images data can reflect the external features, surface defects and contamination. The spectra data can analyze physical structure and chemical composition in studied object. Therefore, hyperspectral imaging technology causes more and more attention, and has become a hot research topic recently. In order to track the latest research developments at home and abroad, application of hyperspectral reflectance and fluorescence imaging techniques to nondestructive detection of agricultural products external quality was reviewed, which would provide reference for application of hyperspectral imaging to agriculture..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2021 (2011)
Mollow Profile with Seven Peaks under Double Coupling Fields
LI Xiao-li, ZHANG Lian-shui, SUN Jiang, and GUO Shu-qing
Transparency and absorption overlaping with Mollow profile in a lambda three-level scheme driven by two coupling fields was investigated. There are two degenerate hyperfine levels within ground state. A strong coupling field and a probing field interact with the same optical transition between the excited state level aTransparency and absorption overlaping with Mollow profile in a lambda three-level scheme driven by two coupling fields was investigated. There are two degenerate hyperfine levels within ground state. A strong coupling field and a probing field interact with the same optical transition between the excited state level and the first ground state hyperfine level, and an additional weak coupling field interacts with the excited state level and the second ground state hyperfine level, which is named double coupling lambda three-level scheme. It can be seen that when the strong coupling field is off-resonant, there is the superposition of Mollow profile with EIT, EIA and other quantum coherent phenomena, namely, Mollow profile with seven peaks. The dependence of the position of the EIT or EIA on Rabi frequency and frequency detuning of the strong coupling field was investigated. The results can be accounted for by dressed-state formalism..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2027 (2011)
Comparative Study on the Gas Temperature of a Plasma Jet at Atmospheric Pressure
JIA Peng-ying, LI Xue-chen, and YUAN Ning
A plasma jet of a dielectric barrier discharge in coaxial electrode was used to produce jet plasma in flowing work gas (argon mixed with trace nitrogen) at atmospheric pressure. The relation between the plasma length and the gas flow rate was obtained by taking the images of the jet plasma. A high-resolution optical spA plasma jet of a dielectric barrier discharge in coaxial electrode was used to produce jet plasma in flowing work gas (argon mixed with trace nitrogen) at atmospheric pressure. The relation between the plasma length and the gas flow rate was obtained by taking the images of the jet plasma. A high-resolution optical spectrometer was used to collect the optical emission spectrum. The emission spectra of the first negative band of N+2(Ｂ ２Σ＋ｕ→Ｘ ２Σ＋ｇ, 390～391.6 nm) were used to estimate the rotational temperature of the plasma plume by fitting the experimental spectra to the simulated spectra. The gas temperature was investigated by this optical method and results show that the gas temperature increases with increasing the applied voltage. For comparison, a thermometer was used to measure the temperature of the gas emitted from the jet. The results also show that the gas temperature increases with increasing the applied voltage. The gas temperatures obtained by the two methods are consistent. The difference was analyzed..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2032 (2011)
Comparative Study of Uniform-Doping and Gradient-Doping Negative Electron Affinity GaN Photocathodes
LI Biao, CHANG Ben-kang, XU Yuan, DU Xiao-qing, DU Yu-jie, FU Xiao-qian, WANG Xiao-hui, and ZHANG Jun-ju
High temperature annealing and Cs/O activation are external incentives, while the property of GaN material is internal factor in the preparation of negative electron affinity GaN photocathode. The similarities and differences of the performance of the two structure photocathodes are analysed based on the difference of High temperature annealing and Cs/O activation are external incentives, while the property of GaN material is internal factor in the preparation of negative electron affinity GaN photocathode. The similarities and differences of the performance of the two structure photocathodes are analysed based on the difference of the structure between uniform-doping and gradient-doping negative electron affinity GaN photocathodes and the changes in photocurrents in activation and the quantum yield after successfully activated of GaN photocathodes. Experiments show that: the photocurrent growth rate is slower in activation, activation time is longer and quantum efficiency is higher after successfully activated of gradient-doping GaN photocathode than those of uniform-doping photocathode respectively. The field-assisted photocathode emission model can explain the differences between the two, built-in electric field of gradient-doping structure creates additional electronic drift to the photocathode surface, and the probability of electrons to reach the photocathode surface is improved correspondingly..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2036 (2011)
Research on Trace Gas Spectral Measurement on Intra-Cavity Fiber Optic Laser
ZHANG Hong-xia, LIU Kun, JIA Da-gong, LIU Tie-gen, PENG Gang-ding, WANG Yan, and ZHANG Yi-mo
Due to the advantages of immunity of electrical/electronic, high performance cost ratio, remote detection and multiplexing capability, intra-cavity fiber optic gas measurement has aroused wide concern. The trace gas measurement system has been developed based on the elaborated gas cell and reflector. The wavelength sweDue to the advantages of immunity of electrical/electronic, high performance cost ratio, remote detection and multiplexing capability, intra-cavity fiber optic gas measurement has aroused wide concern. The trace gas measurement system has been developed based on the elaborated gas cell and reflector. The wavelength sweeping technique (WST) is realized when the Fabry-Perot type tunable optical filter is applied by the sawtooth driver voltage. Multi absorption lines can be obtained and one scanning measurement with WST is equal to multiple independent detections, so the gas measurement sensitivity is improved remarkably. The experimental results show that the acetylene detection sensitivity is reduced to less than 100 ppm and the relative measurement error is less than 3％ of practical gas concentration..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2040 (2011)
Research on Gas Detection Based on Spectrum Scanning Techniques of Ultra-Narrow-Bandwidth Laser
CHEN Xiao, SUI Qing-mei, MIAO Fei, WANG Jing, and JIANG Ming-shun
Based on the basic principle of differential absorption detection and the spectrum scanning technology of ultra-narrow-bandwidth (UNB) laser, a kind of distributed carbon dioxide detection system with high precision was designed. An UNB laser was utilized as light source and a novel structure gas cell was also used in Based on the basic principle of differential absorption detection and the spectrum scanning technology of ultra-narrow-bandwidth (UNB) laser, a kind of distributed carbon dioxide detection system with high precision was designed. An UNB laser was utilized as light source and a novel structure gas cell was also used in this system. By using the wavelength modulation technique and space division multiple access technique, the interference of other gas and dust was eliminated and the distributed detection of carbon dioxide was achieved. With the spectrum scanning technology of UNB laser, spectra of carbon dioxide near the region of 1 572.66 μm at different pressures were obtained which were also analyzed. Finally the experiments indicated that the minimum detectable carbon dioxide is 0.005% and the measurement relative error is less then 3%. The system dynamic response time is less than 8 s by filling a volume of carbon dioxide gas into the gas cell gradually..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2044 (2011)
Spectral Analysis of Different Boundary Discharge Domain in Dielectric Barrier Discharge
CHEN Jun-ying, DONG Li-fang, JI Ya-fei, LI Yuan-yuan, and SONG Qian
Different discharge modes in different boundary discharge domains at the same experimental condition are observed in argon/air mixture in a dielectric barrier discharge system with two large diameter water electrodes. Regular patterns and random filaments are formed in the closed square boundary and the semiopen domainDifferent discharge modes in different boundary discharge domains at the same experimental condition are observed in argon/air mixture in a dielectric barrier discharge system with two large diameter water electrodes. Regular patterns and random filaments are formed in the closed square boundary and the semiopen domain respectively. It is found that the relatively intensity of the several higher excitation energy spectral lines such as 696.5, 727.3, 750.4 and 772.4 nm increases with the applied voltage in the closed boundary domain while decreases in the semiopen domain. Results show that the electron average energy in the closed boundary is higher than that in the semiopen domain and the difference of the electron average energy increases with the applied voltage. The results of molecular vibration temperature estimated by the second positive spectrum of N2 molecular indicate that the vibration temperature increases with the applied voltage in the closed boundary and decreases with the applied voltage in the semiopen boundary domain..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2049 (2011)
Influence of Y3+, Bi3+ Content on Photoluminescence of YVO4∶Dy3+ Phosphor Induced by Ultraviolet Excitation
HE Yu-yang, ZHAO Mai-qun, SONG Yan-yan, ZHAO Gao-yang, and LI Feng
YxVO4∶0.01Dy3+ and Y0.99-xVO4∶0.01Dy3+, xBi3+ phosphors were synthesized by chemical co-precipitation method. Their crystal structure, micromorphology and photoluminescence (PL) properties were investigated by X-ray diffraction (XRD), scan electron microscopy (SEM) and spectrofluorometer. YxVO4∶0.01Dy3+ and Y0.99-xVO4∶YxVO4∶0.01Dy3+ and Y0.99-xVO4∶0.01Dy3+, xBi3+ phosphors were synthesized by chemical co-precipitation method. Their crystal structure, micromorphology and photoluminescence (PL) properties were investigated by X-ray diffraction (XRD), scan electron microscopy (SEM) and spectrofluorometer. YxVO4∶0.01Dy3+ and Y0.99-xVO4∶0.01Dy3+, xBi3+ phosphors have a broad excitation band from about 250 to 350 nm including a strongest peak at about 310 nm. Under its excitation, the emission spectra exhibits two sharp peaks, one of which centered at about 483 nm for 4F9/2→6H15/2 transition of Dy3+ and the other at about 574 nm due to the 4F9/2→6H13/2 transition of Dy3+. For YxVO4∶0.01Dy3+ (x=0.94, 0.97, 0.99, 1.01, 1.03) phosphor, with increasing value of x, the body color of phosphor changes from yellow to white and the strongest peak in the excitation spectra shifts a little to shorter wavelength. It is detrimental to luminous intensity when Y3+ content deviates stoichiometric ratio. For Y0.99-xVO4∶0.01Dy3+, xBi3+ (x=0.01, 0.05, 0.1, 0.15, 0.2, 0.25) phosphor, the samples have extraneous bismuth vanadium oxide phase except for the major tetragonal zircon structure when x≥0.20. With increasing value of x, the band edge in the excitation spectra shifts to longer wavelength, the excitation intensity and luminous intensity increase early and decrease late. When the value of x is 0.01, the intensities increase evidently. In addition, the influence of Y3+ or Bi3+ on the color temperature of emission and micromorphology of YVO4∶Dy3+ is slight..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2053 (2011)
Preparation and Luminescence Characteristics of White-Light Emitting Ca9.95-xNa0.75K0.25(PO4)7∶Eu2+0.05, Mn2+x Phosphors
ZHOU Guo-xiong, ZHAO Wei-ren, SONG En-hai, DOU Xi-hua, YI Chun-yu, and ZHOU Min-kang
The Ca9.95-xNa0.75K0.25(PO4)7∶Eu2+0.05, Mn2+x（x=0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6 and 0.7) phosphors were synthesized by high temperature solid-state reaction, and their phase composition and fluorescence emission properties were studied. Due to the existence of double phases with similar crystal structure, the 5d-4f traThe Ca9.95-xNa0.75K0.25(PO4)7∶Eu2+0.05, Mn2+x（x=0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6 and 0.7) phosphors were synthesized by high temperature solid-state reaction, and their phase composition and fluorescence emission properties were studied. Due to the existence of double phases with similar crystal structure, the 5d-4f transition of Eu2+ ions in the phosphors emits a fluorescence of wide wavelength with peaks located at 491 nm and 540 nm respectively. The energy transfer between Eu2+ and Mn2+, together with the occupation of Mn2+ ions at the eight coordination sites in the phosphors, makes the 4T1(4G)-6A1(6S) transition of Mn2+ ions eimit red emission peaked at 635 nm. The combination of fluorescence emtted by Mn2+ and Eu2+ ions results in the emission of white light with color coordinates (0.333 5, 0.292 4), (0.399 9, 0.317 9) and (0.330 7, 0.256 4). The nearly pure white light emitting makes the phosphors show great application potential in the white light-emitting LEDs..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2058 (2011)
Luminescence Properties of Thenardite Activated with Dy3+ under Vacuum Ultraviolet Excitation
Taximaiti Yusufu, Ajimu Abulai, SU Zong-cai, and Aierken Sidike
Na2SO4∶Dy3+ phosphors were prepared by heating pure natural thenardite(Na2SO4) with DyF3 at 900 ℃ for 25 min in air. studied the Luminescence properties of Na2SO4∶Dy3+ were studied by synchrotron radiation. Their photoluminescence (PL) spectra were also investigated under vacuum ultraviolet-ultraviolet (VUV-UV) at roomNa2SO4∶Dy3+ phosphors were prepared by heating pure natural thenardite(Na2SO4) with DyF3 at 900 ℃ for 25 min in air. studied the Luminescence properties of Na2SO4∶Dy3+ were studied by synchrotron radiation. Their photoluminescence (PL) spectra were also investigated under vacuum ultraviolet-ultraviolet (VUV-UV) at room temperature.According to the emission spectra, the yellow-blue ratio (Y/B) is different under different concentrations of Dy3+ and the position of excitation.And the excitation spectrum is consisted of strong bands assigned to the 4f9→4f8 5d transition at 172 nm, the O2-- Tm3+charge transfer band at 165 nm and weak bands assigned to host absorption(138, 245 nm) and the 6H15/2→4D7/2,6H15/2→6P3/2, and 6H15/2→6P7/2 transition at 299, 325 and 351 nm respectively..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2063 (2011)
A Study of Photoluminescence Properties of Si-Based CeO2/Tb4O7 Superlattices
WANG Shen-wei, YI Li-xin, DING Jia-cheng, GAO Jing-xin, GUO Li-da, and WANG Yong-sheng
CeO2/Tb4O7 superlattices were deposited on P type Si wafers by e-beam evaporation technology. Four typical photoluminescence peaks of Tb3+ ions which located around 488, 544, 588 and 623 nm were obtained after the superlattices annealing in weak reducing atmosphere at high temperature. It was indicated that CeO2 films CeO2/Tb4O7 superlattices were deposited on P type Si wafers by e-beam evaporation technology. Four typical photoluminescence peaks of Tb3+ ions which located around 488, 544, 588 and 623 nm were obtained after the superlattices annealing in weak reducing atmosphere at high temperature. It was indicated that CeO2 films transferred to amorphous state as the valence transition of Ce4+→Ce3+ which was induced by thermal annealing, the energy transfer occurred between Ce3+ ions and Tb3+ ions, and the Tb3+ ions emition could be detected after obtaining the energy from Ce3+ ions. A study about the effect of Tb4O7 thickness on the superlattices photoluminescence showed that the maximum PL intensity as thickness of Tb4O7 films were about 0.5 nm, the concentration quenching might occur because of the energy transfer among the Tb3+ ions. The annealing conditions research demonstrated that the maximum PL intensity could be obtained as the superlattices annealed at 1 200 ℃ for 2 hour. Further investigation inferred that the concentration of Ce3+ ions, Oxygen vacancy defects and the distance between Ce3+ ions and Tb3+ ions play an important role in the annealing process..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2067 (2011)
Research on Synthesis and Luminous Mechanism of a Soluble Blue-Light Luminescence Material Derived from Carbazole
LI Juan, WANG Hua, SONG Chun-li, ZHANG Cun, ZHANG Jun-ping, HAO Yu-ying, and XU Bing-she
In the present paper, a kind of blue light-emitting organic small molecule luminescent materials was designed and synthesized, which is composed of carbazole and 8-benzyloxyquinoline functional groups. Alkyl chain can effectively play the role of electron transfer barrier. The synthesis principle was on the basis of thIn the present paper, a kind of blue light-emitting organic small molecule luminescent materials was designed and synthesized, which is composed of carbazole and 8-benzyloxyquinoline functional groups. Alkyl chain can effectively play the role of electron transfer barrier. The synthesis principle was on the basis of the mechanisms of SN1nucleophilic reaction and SUZUKI coupling reaction mechanisms. It is entitled N-［6-(8-benzylquinoline)-hexyl］carbazole (CZBQ). Its molecular structure was simulated and optimized by Gaussian03. Its chemical structure was identified by measurements of ultraviolet-visible spectra and H1 NMR spectra. It photo physical property was characterized by method of fluorescence spectra. t is indicated that CZBQ was a kind of blue-light luminescence material and its optical band gap is 3.02 eV. Ethanol solution of CZBQ exhibits the maximal emission peak at 410 nm in photoluminescence spectra. In the luminescence process of CZBQ, carbazole groups and 8-benzylquinoline groups were separately involved in excitation and light emission. This kind of blue-light luminescence material possesses excellent solubility, It can be dissolved in different solvents such as ethanol and ethyl acetate and dichloromethane. The test results of AFM show that CZBQ was provided with very good film formability. It is expected to be utilized in blue-light organic light-emitting device fabricated by wet method such as spin-coding method and screen printing..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2071 (2011)
Thickness Measurement of Insulation Coating by NIR Spectrometry Based on Boosting-KPLS
HAO Hui-min, LI Shi-wei, ZHANG Wen-dong, LI Peng-wei, HAO Jun-yu, LU Hai-ning, Ken Jia, and ZHANG Yong
A novel thickness measurement method for surface insulation coating of silicon steel based on NIR spectrometry is explored. The NIR spectra of insulation coating of silicon steel were collected by acousto-optic tunable filter (AOTF) NIR spectrometer. To make full use of the effective information of NIR spectral data, dA novel thickness measurement method for surface insulation coating of silicon steel based on NIR spectrometry is explored. The NIR spectra of insulation coating of silicon steel were collected by acousto-optic tunable filter (AOTF) NIR spectrometer. To make full use of the effective information of NIR spectral data, discrete binary particle swarm optimization (DBPSO) algorithm was used to select the optimal wavelength variates. The new spectral data, composed of absorbance at selected wavelengths, were used to create the thickness quantitative analysis model by kernel partial least squares (KPLS) algorithm coupled with Boosting. The results of contrast experiments showed that the Boosting-KPLS model could efficiently improve the analysis accuracy and speed. It indicates that Boosting-KPLS is a more accurate and robust analysis method than KPLS for NIR spectral analysis. The maximal and minimal absolute error of 30 testing samples is respectively -0.02 μm and 0.19 μm, and the maximal relative error is 14.23%. These analysis results completely meet the practical measurement need..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2081 (2011)
Absorbance of Infrared Bands and Anomalous Absorption
YANG Yan-hua, LI Hui-jing, and WANG Hai-shui
To remove the background signals from an IR spectrum is very useful and ideally all that remain in an IR spectrum are the desired absorption bands. Unfortunately, the removal of background bands is not always completely effective. In the present paper, an absorbance spectrum was obtained by scanning the same sample (poTo remove the background signals from an IR spectrum is very useful and ideally all that remain in an IR spectrum are the desired absorption bands. Unfortunately, the removal of background bands is not always completely effective. In the present paper, an absorbance spectrum was obtained by scanning the same sample (polystyrene film or stearic acid KBr disc) both in background and sample single-beam measurements. It was found that a series of residual spikes appear in the strong absorption regions. The residuals are significantly different from that of random noise. There should be a nearly straight line according to theory analysis while spikes appear. Therefore those spikes are called anomalous absorption. The experimental results indicate that anomalous absorption is related to the absorbance of infrared bands. If the absorbance of an infrared band is lower than 1.0, anomalous absorption can be suppressed thoroughly. In addition, absorption anomalies can be substantially reduced by reducing the spectral resolution of the spectrum. The reasons for anomalous absorption were discussed and how to prevent the appearance of anomalous absorption by selecting appropriate background samples were suggested..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2086 (2011)
FTIR Analysis of Cosrelation between Emulsifying Properties and the Secondary Structure of the Proteins in Modified Egg Yolk Powder
GE Shao-yang, LIU Mei-yu, ZHU Jun, WANG Fang, REN Fa-zheng, ZHANG Lu-da, and GUO Hui-yuan
Spray drying is an important processing of producing modificatied yolk powder (MEYP). To investigate the correlation between the secondary structure and emulsifying property of MEYP made at different spray-drying-temperatures, Fourier transform infrared spectroscopy (FTIR) was applied in the present study. The result iSpray drying is an important processing of producing modificatied yolk powder (MEYP). To investigate the correlation between the secondary structure and emulsifying property of MEYP made at different spray-drying-temperatures, Fourier transform infrared spectroscopy (FTIR) was applied in the present study. The result indicated that emulsifiability and the percentage of α-helix were both significantly increased firstly and then remarkably decreased with rising of spray-drying-temperature, and the emulsifying property of MEYP was relative to the percentage of α-helix. After heat-treating, the percentage of α-helix was significantly decreased and the percentage of β-sheet was remarkably increased, however, the total percentage of the two structures was maintained. The stable total percentage of α-helix and β-sheet would be a good explanation for the great heat stability of emulsion presented in the MEYP made at different spray-drying temperature..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2090 (2011)
Identification of Soil-Borne Fungi Using Fourier Transform Infrared Spectroscopy
CHAI A-li, LI Bao-ju, SHI Yan-xia, and XIE Xue-wen
Fourier transform infrared (FTIR) attenuated total reflectance (ATR) spectroscopy was used in combination with multivariate statistic analysis for identification of soil-borne fungi that causes severe economic damage to agriculture: Fusarium moniliforme, Fusarium semitectum, Fusarium oxysporum, Fusarium solani, RhizoctFourier transform infrared (FTIR) attenuated total reflectance (ATR) spectroscopy was used in combination with multivariate statistic analysis for identification of soil-borne fungi that causes severe economic damage to agriculture: Fusarium moniliforme, Fusarium semitectum, Fusarium oxysporum, Fusarium solani, Rhizoctonia solani, Sclerotinia sclerotiorum, Pythium aphanidermatum and Phytophthora capsici. The original FTIR spectra were normalized, and the second derivatives were calculated, from which the peak wave numbers showing greatest variability were selected: 2 924, 2 854, 1 745, 1 641, 1 547, 1 466, 1 406, 1 376, 1 306, 1 240, 1 201, 1 152, 1 109 and 1 028 cm-1. To discriminate different fungal strains, canonical discriminant analysis and cluster analysis were performed at these characteristic wave numbers. Results showed that the classification accuracies achieved 100% for different species of fungi, and classification accuracies for different fusarium strains achieved 95.56%, demonstrating the high potential of this technique for fungi identification..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2094 (2011)
Near-Infrared Spectroscopy Quantitative Analysis Model Based on Inverse Regression
LIU Xu-hua, MIN Shun-geng, HE Xiong-kui, and ZHANG Lu-da
In the present paper, an inverse regression method is used in near infrared (NIR) spectroscopy analysis to reduce dimension of predictor at first, then estimate linear regression function using the new derived low dimensional data. A real data set of 103 corn samples was used for analysis with this new inverse regressiIn the present paper, an inverse regression method is used in near infrared (NIR) spectroscopy analysis to reduce dimension of predictor at first, then estimate linear regression function using the new derived low dimensional data. A real data set of 103 corn samples was used for analysis with this new inverse regression method. Taking 103 corn samples as experiment materials, seventy samples were chosen randomly to establish predicting model, the remaining thirty-three corn samples were viewed as prediction set. The new derived model is used to the prediction set. The coefficient is 0.986 and the average relative error is 2.1% between the model predication results and Kjeldahl’s value for the protein content, and the results of using partial least square regression are 0.978 and 2.5%, respectively. The results demonstrate that the inverse regression method is feasible and has good property in near-infrared spectroscopy quantitative analysis, and also provides a new idea for chemometrics quantitative analysis..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2098 (2011)
Application of Near-Infrared Spectrum Technology to Research of Weathering of Red Sandstone Relics
JIANG Xiao-dong, CAO Jian-jin, LI Yi-an, YIN Jin-long, and YE Jin-long
In the present paper, with near infrared spectroscopy technology, the weathering mechanism of red sandstone relics was studied. Six groups of red sandstone samples were analyzed using near infrared spectroscopy technology. The results show that the near-infrared spectroscopy technology can analyze the material compositIn the present paper, with near infrared spectroscopy technology, the weathering mechanism of red sandstone relics was studied. Six groups of red sandstone samples were analyzed using near infrared spectroscopy technology. The results show that the near-infrared spectroscopy technology can analyze the material composition of red sandstone before and after weathering, aiming to explore their components changed. So it is a quick and efficient means of research with characteristic of less measurement sample and speed and non-damage and being pollution-free compared with other research techniques. All the characteristic shows that it is also well for studying other stone cultural relics. Especially for those with sampling difficulty and treasure valuable, non-destruction of stone cultural relics is particularly important. So with time advancing, near infrared technology as a research means of stone relics, its meaning will be more prominent..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2102 (2011)
The Application of Near-Infrared Spectroscopy and Pattern Recognition to Quality Assessment of Toothpaste Samples of Different Brands
LIN Wei, and NI Yong-nian
The near-infrared spectroscopy (NIR) was combined with pattern recognitions method and applied to the quality assessment of toothpaste samples of four different brands. Several chemometrics approaches, such as principal component analysis (PCA), clustering analysis (CA), partial least squares (PLS), artificial neural nThe near-infrared spectroscopy (NIR) was combined with pattern recognitions method and applied to the quality assessment of toothpaste samples of four different brands. Several chemometrics approaches, such as principal component analysis (PCA), clustering analysis (CA), partial least squares (PLS), artificial neural networks (ANN) and K-nearest neighbor (kNN) were used to investigate the quality of toothpastes samples. The obtained results showed that the four clustering groups can be observed after the pretreatment of multiple scatter correction for the NIR data. It was also found that the quality of toothpastes of all the four brands was relatively stable, however, there is a significant difference in the quality between two brand kinds of toothpaste samples..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2106 (2011)
Infrared Spectral Analysis for Calcined Borax
ZHAO Cui, REN Li-li, WANG Dong, ZHOU Ping, ZHANG Qian, and WANG Bo-tao
To valuate the quality of calcined borax which is sold in the market, 18 samples of calcined borax were studied using the Fourier transform infrared, and samples with different water content were selected and analyzed. Then, the results of analysis were used to evaluate the quality of calcined borax. Results show that To valuate the quality of calcined borax which is sold in the market, 18 samples of calcined borax were studied using the Fourier transform infrared, and samples with different water content were selected and analyzed. Then, the results of analysis were used to evaluate the quality of calcined borax. Results show that the infrared spectra of calcined borax include OH vibration, BO3-3 vibration and BO5-4 vibration absorption bands. The position and width of OH vibration absorption band depend on the level of water content, and the more the water content, the wider the absorption band. The number of BO3-3 vibration and BO5-4 vibration bands also depend on the level of water content, and the more the water content, and the stronger the hydrogen bond and the lower the symmetry of B atoms, the more the number of infrared absorption peaks. It was concluded that because the quality of calcined borax has direct correlation with water content, the infrared spectroscopy is an express and objective approach to quality analysis and evaluation of calcined borax..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2109 (2011)
Application of NIRS to Detecting Total N of Cucumber Leaves Growing in Greenhouse
RUI Yu-kui, XIN Shu-zhen, and LI Jun-hui
Non-destructive testing, as a new, rapid, non-destructive technology, is the direction of agricultural produce testing in the future. In this study, the nitrogen content of cucumber leaves was predetermined using near infrared spectroscopy technology. The main results were as follows: The authors measured the nitrogen Non-destructive testing, as a new, rapid, non-destructive technology, is the direction of agricultural produce testing in the future. In this study, the nitrogen content of cucumber leaves was predetermined using near infrared spectroscopy technology. The main results were as follows: The authors measured the nitrogen content in cucumber leaves with Kjeldahl method and near infrared spectroscopy, then established a model between them, and processed a external verification next. The verification results showed that the determination coefficient of the model was 0.406 6, relative standard deviation is 0.155 9, and calibration standard deviation is 0.72； Then the authors predicted the cucumber leaves nitrogen content with this model, and the results showed that the mean absolute percent error was 0.59, average relative error was 13.88, and correlation coefficient of the chemical values and predicted values was 0.637 7. So it was proved that this model had a certain feasibility in vegetable leaves nitrogen testing..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2114 (2011)
Research on Raman Spectra of Calcite Phase Transition at High Pressure
WANG Shi-xia, and ZHENG Hai-fei
The present research studied the process of phase transition from calcite-Ⅰ to calcite-Ⅲ under the condition of high hydrostatic pressure using hydrothermal diamond anvil cell and Raman spectrum technique. The hydrothermal diamond anvil cell is the most useful instrument to observe sample in-situation under high temperThe present research studied the process of phase transition from calcite-Ⅰ to calcite-Ⅲ under the condition of high hydrostatic pressure using hydrothermal diamond anvil cell and Raman spectrum technique. The hydrothermal diamond anvil cell is the most useful instrument to observe sample in-situation under high temperature and high pressure. The authors can get effective results from this instrument and pursue further research. The method of Raman spectra is the most useful measure tool and it can detect the material according to the spectrum. The result shows that three characteristic Raman peaks of calcite-Ⅰ move to high-position with adding pressure. Water media in system becomes frozen at the pressure of 1 103 MPa, and there is no change in the structure of calcite-Ⅰ. The abrupt change of characteristic Raman peaks of calcite -Ⅰ happens when the system pressure reaches 1 752 MPa, and changed characteristic Raman peaks explain that calcite-Ⅰ changes to calcite-Ⅲ. There are two types of calcite-Ⅲ, and type A happens in the system because of the effect of hydrostatic pressure. The characteristic Raman peak in different areas of minerals shows that the degree of phase transition becomes larger from inner part to edge part. The research also shows the advantage of hydrothermal diamond anvil cell and Raman spectrum for qualitative analysis of mineral structure using in-situ technique..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2117 (2011)
Study of Quartz’s Roman Spectrum at High Pressure and Room Temperature
LI Yue, YAN Shi-yong, and CHEN Yong
Phase transition of quartz is widely used in the high pressure experiment as the standard of pressure correcting of the laboratory instrument. And the quartz is usually used as the pressure sensor in the experiment when the pressure is low. Christian S et al discussed the function between the pressure and the shift of Phase transition of quartz is widely used in the high pressure experiment as the standard of pressure correcting of the laboratory instrument. And the quartz is usually used as the pressure sensor in the experiment when the pressure is low. Christian S et al discussed the function between the pressure and the shift of quartz’s Raman spectrum peak when the shift isn’t exceeding 20 cm-1. In order to extend the applying range, the authors discussed the function again using the diamond anvil cell, and used ruby as the pressure sensor which is widely used in the high pressure experiment. After discussing the function, we obtained a new function that is P(MPa)=-1.094 83E7+67 495.237 31×ΔＶ-138.706 91(ΔＶ)2+0.095 04(ΔＶ)3 which is different from the Christian’s function..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2120 (2011)
Density Functional Theory Calculation of SERS Spectra of Trans-1,2-Bis(4-Pyridyl)-Ethylene on Silver
ZHUANG Zhi-ping, ZHAO Bing, CHEN Yu-feng, and ZUO Ming-hui
It has been found that trans-1,2-bis(4-pyridyl)-ethylene has the best SERS signal and can be employed as a kind of self-assembly ?lm for the exploration of the SERS-active on the silver foil substrate. The shifts in the experiment surface enhanced Raman scattering of trans-1,2-bis(4-pyridyl)-ethylene were simulated by It has been found that trans-1,2-bis(4-pyridyl)-ethylene has the best SERS signal and can be employed as a kind of self-assembly ?lm for the exploration of the SERS-active on the silver foil substrate. The shifts in the experiment surface enhanced Raman scattering of trans-1,2-bis(4-pyridyl)-ethylene were simulated by density functional theory calculation with the BP86, BPw91, B3LYP method. The basis set of 6-31++G(d,p) and Lanl2dz was used by H, C, N atoms and Ag atom for the t-BPE-Ag complex. The Raman spectra and surface enhanced Raman scattering of trans-1,2-bis(4-pyridyl)-ethylene were assigned by the calculated results of potential energy distribution. The density functional theory calculated results explain that the angles between pyridyl rings for t-BPE-Ag complex holding 0o. Thus, the calculated Raman spectra of trans-1,2-bis(4-pyridyl)-ethylene and Ag complex accord with observed SERS results of t-BPE. The energy level space between the high occupied molecular orbital and lowest unoccupied molecular orbital is estimated to arise between 415 and 912 nm for trans-1,2-bis(4-pyridyl)-ethylene and Ag complex..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2123 (2011)
Study of Raman Technique Applied to Estrogen
FENG Chao, DONG Kun, WU Yong-jun, and ZHANG Peng-xiang
The authors acquired Raman spectra of three kinds of estrogen by portable Raman spectrometer, including 17β-estradiol (C18H24O2), estriol (C18H24O3) and diethylstilbestrol (C18H20O2). Analysis, comparison and simulation of the three estrogens were carried out, and the diethylstilbestrol Raman spectrum, which is hard toThe authors acquired Raman spectra of three kinds of estrogen by portable Raman spectrometer, including 17β-estradiol (C18H24O2), estriol (C18H24O3) and diethylstilbestrol (C18H20O2). Analysis, comparison and simulation of the three estrogens were carried out, and the diethylstilbestrol Raman spectrum, which is hard to detect, was acquiredt by surface enhanced Raman scattering technology. Results show that Raman technique can detect 17β-estradiol (C18H24O2), estriol (C18H24O3) and diethylstilbestrol (C18H20O2) quickly and accurately..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2127 (2011)
Effect Freezing and Thawing Cycles on Fluorescence Characterization of Black Soil Dissolved Organic Matter
WANG Tai-ming, WANG Ye-yao, XIANG Bao, and HU Yu
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2136 (2011)
Comparisons of Spectral Properties of CsI∶Tl Crystals with Various Tl+-Doped Concentrations
WU Zheng-long
Absorption Spectra and Photoluminescence (PL) spectra of CsI∶Tl crystals with various Tl+-concentrations were measured for absorption and luminescent research in CsI∶Tl. Their UV absorption spectra contained three peaks at 297, 273 and 247 nm. The experiments were demonstrated that the peaks in the high Tl+-concentratiAbsorption Spectra and Photoluminescence (PL) spectra of CsI∶Tl crystals with various Tl+-concentrations were measured for absorption and luminescent research in CsI∶Tl. Their UV absorption spectra contained three peaks at 297, 273 and 247 nm. The experiments were demonstrated that the peaks in the high Tl+-concentration CsI∶Tl crystals are broader than ones in the low Tl+-concentration crystals and their absorption A-peak shift by 20 nm, but their PL with UV excitations are similar. It was suggested that lattice distortions in the high Tl+-concentration CsI∶Tl lead to the changes in absorption or fluorescence excitation peaks, but no changes in the fluorescence band widths and locations at room temperature..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2141 (2011)
Synthesis and Fluorescence Properties of the Complexes［(TbxY1-x)(HL)L′Cl·1/2H2O］
WU Ren-qimuge, ZHAO Yong-liang, MA Rui-jun, LIN Xue-mei, SUN Hui-juan, LI Xin, LI Hai-yan, and LI Yuan
By replacing a part of terbium ions with yttrium ions using doping method, a series of dinuclear complexes of 1, 3, 5-benzene tricarboxylic acid (H3BTC) and phenanthroline (phen) with different molar ratios of Tb3+ to Y3+ were synthesized in the present paper. Their elemental analysis, rare earth complexometric titratiBy replacing a part of terbium ions with yttrium ions using doping method, a series of dinuclear complexes of 1, 3, 5-benzene tricarboxylic acid (H3BTC) and phenanthroline (phen) with different molar ratios of Tb3+ to Y3+ were synthesized in the present paper. Their elemental analysis, rare earth complexometric titration, molar conductivity, IR spectra and UV spectra were studied, and the contents of terbium and yttrium of three doped complexes were measured by a plasma emission spectrophotometer. Their chemical formula is inferred to be (TbxY1-x)(HL)L′Cl·1/2H2O (x=0.10, 0.30, 0.50, 0.70, 0.90, L=BTC3-, L′=phen). The infrared spectra and ultraviolet spectra were determined, the results showed that the rare earth ions are bounded with the oxygen atoms of trimesic acid, and with the nitrogen atoms of phenanthroline. The fluorescence spectra of the complexes were determined at the room temperature (the exit and entrance slits are both 1.5 nm). The fluorescence intensity of terbium doped yttrium complexes is stronger than those of the terbium complex; it was showed that the fluorescence intensity of Tb3+ ion is greatly enhanced by Y3+ ion in the complexes. The fluorescence intensity of (Tb0.7Y0.3)(HL)L′Cl·1/2H2O complex is the strongest among the six complexes. The lowest excitation state energy level of Tb3+ ion and the triplet state energy level of the ligands (H3BTC and phen) match well each other, and the absorbing energy of the ligands is effectively transferred to Tb3+ ion..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2144 (2011)
Feasibility of Using Laser-Induced Fluorescence to Detect Directly Polycyclic Aromatic Hydrocarbons in Soil
YANG Ren-jie, SHANG Li-ping, BAO Zhen-bo, HE Jun, DENG Hu, and LIU Yu-le
In the present paper, a technique of laser-induced fluorescence（LIF）for direct assay of polycyclic aromatic hydrocarbons(PAH) in soil was put forward. The research objective of this article is anthracene. The possibility of using LIF spectra to detect directly anthracene in soil was studied. Anthracene was detected in In the present paper, a technique of laser-induced fluorescence（LIF）for direct assay of polycyclic aromatic hydrocarbons(PAH) in soil was put forward. The research objective of this article is anthracene. The possibility of using LIF spectra to detect directly anthracene in soil was studied. Anthracene was detected in soil by AvaSpec-3648 Fiber Optic Spectrometer of thermoelectric refrigeration. The authors drew a conclusion that in the range of certain anthracene concentration(0.000 005～0.001 g·g-1), the intensity of LIF fluorescence is linear with anthracene concentration in soil, with a regression coefficient of 0.929. This showed that direct assay of anthracene in soil was feasible by laser-induced fluorescence. The study is important to developing a new analytical technique of quantitative fluorescence detector which can be applied to the analysis of PAH in soil without pretreatment, and is significant to realization of real-time, in-line, in-situ measurement of PAH in soil..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2148 (2011)
Study on the Interaction of Quercetin with β-Glucosidase by Fluorescence Spectroscopy and Molecular Docking
YU Cai-hong, ZHANG Yao-dong, GAO Qun-qun, HEI Ting-ting, LI Li, and ZHANG Qi
Combined with molecular docking model, a fluorescence method was applied to investigate the interaction between quercetin and β-glucosidase and the acting mechanism. The interaction between β-glucosidase and quercetin, as well as the enzyme inhibitor 4-nitrophenyl-β-D-thioglucoside, was studied by the AutoDock4.2 molecCombined with molecular docking model, a fluorescence method was applied to investigate the interaction between quercetin and β-glucosidase and the acting mechanism. The interaction between β-glucosidase and quercetin, as well as the enzyme inhibitor 4-nitrophenyl-β-D-thioglucoside, was studied by the AutoDock4.2 molecular docking model, respectively. The binding reaction was simultaneously studied using fluorescence quenching method. The results showed that these interactions result in the endogenous fluorescence quenching of β-glucosidase, which belongs to a static quenching mechanism. The calculated binding constants were 4.36×104, 4.04×104 and 3.18×104 L·mol-1 at 17, 27 and 37 ℃, respectively. The results revealed that quercetin tended to bind with β-glucosidase mainly by hydrogen bond and hydrophobic interaction, as well as electrostatic forces. Both fluorescence spectroscopy and molecular docking are complementary to each other for the investigation of the interaction between β-glucosidase and quercetin from the experimental and theoretical view..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2151 (2011)
Spectroscopic Study on the Performance of 1,3-Thiacalix <参考文献原文>Rhodamine Ethyldiamine Amide Derivatives to Fe3+ Ion
ZHANG Wen-juan, ZHENG Xiang-yong, ZENG Xi, MU Lan, and Takehiko Yamato
The two di-substituted rhodamine-based thiacalixarene ethyldiamine amide derivative were synthesized from thiacalixarene and rhodamine B ethyldiamine by acylation. Under the experimental conditions, the derivatives and Fe3+ are able to form a 1∶1 complex. The formation of complex leaded to the moiety opening of rhodamiThe two di-substituted rhodamine-based thiacalix<参考文献原文>arene ethyldiamine amide derivative were synthesized from thiacalix<参考文献原文>arene and rhodamine B ethyldiamine by acylation. Under the experimental conditions, the derivatives and Fe3+ are able to form a 1∶1 complex. The formation of complex leaded to the moiety opening of rhodamine, and showed the good fluorescent and colorimetric performance. Among them, the selectivity of 1,3-thiacalix<参考文献原文> rhodamine ethylenediamine amide-2,4-ester to Fe3+ is higher than 1,3-thiacalix <参考文献原文> rhodamine ethylenediamine amide-2,4-acid. The analysis feature of the probes response to Fe3+ was studied by spectroscopy, and synthetic samples were determinec..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2156 (2011)
The Common and Variation Peak Ratio Dual Index Sequence Analysis in UV Fingerprint Spectra of Gentiana Rigescens
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]
With the common and variation peak ratio dual index sequence analysis method, using mean value, smoothness and derivative processing methods to calibrate and exclude interference, in order to increase resolution of spectrum, and then inspected the RSD of stability and repeatability of three different polarity solvent eWith the common and variation peak ratio dual index sequence analysis method, using mean value, smoothness and derivative processing methods to calibrate and exclude interference, in order to increase resolution of spectrum, and then inspected the RSD of stability and repeatability of three different polarity solvent extracts of Gentiana rigescens, calculated the common and variation peak ratio in the UV fingerprint spectral, to evaluate the quality of G. rigescens from different areas. The results showed that, at 40 min, the extract ratio was the best in chloroform, absolute ethyl alcohol or water, and in 30h the RSD of stability respectively were between 0.078~0.455, 0.158~0.462, 0.052~0.682; the RSD of repeatability respectively were between 0.044~0.753, 0.156~0.288, 0.191~2.413. The fingerprint spectral implicated that the largest common peak ratio was 67.6%, while the least was 45.2%, and the largest variation peak ratio was 78.9%, the least was 21.7% among different areas of G. rigescens. The method could be used exactly in qualitative evaluation of two more herb samples, and clarified the similarity level among different areas, also applied the basement for authenticity identification and quality evaluation of herbs..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2161 (2011)
A New Spectral Similarity Measure Based on Multiple Features Integration
KONG Xiang-bing, SHU Ning, TAO Jian-bin, and GONG Yan
Spectral characterization and feature selection is the key to spectral similarity measure which is the basis of both quantitative analysis and accurate object identification for hyperspectral remote sensing. However, spectral similarity measures using only one spectral feature are usually ambiguous in their distinctionSpectral characterization and feature selection is the key to spectral similarity measure which is the basis of both quantitative analysis and accurate object identification for hyperspectral remote sensing. However, spectral similarity measures using only one spectral feature are usually ambiguous in their distinction of similarity. Multiple spectral features integration is needed for objective spectral discrimination. We present a new spectral similarity measure, Spectral Pan-similarity Measure (SPM), based on geometric distance, correlation coefficient and relative entropy. Spectral Pan-similarity Measure objectively quantifies differences between spectra in three spectral features, the vector magnitude, spectral curve shape and spectral information content. The performance of different spectral similarity measures is compared using USGS Mineral Spectral Library and real (i.e., Operational Modular Imaging Spectrometer, OMIS) hyperspectral image. The experimental results demonstrate that the new spectral similarity measure is more effective than the spectral similarity measure taking into account only one or two features both in spectral discriminatory power and spectral identification uncertainty..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2166 (2011)
Study on Spectra Properties of Novel Octa-Substituted Phthalocyanines
XIA Dao-cheng, LI Wan-cheng, WANG Hong-fu, ZHENG Xin-xing, GUO Yan-jie, and YANG Xu-qing
The spectrum properties of four novel 1,4,8,11,15,18,22,25-octaoxybutyl copper phthalocyanine; 1,4,8,11,15,18,22,25-octamethoxybutanoate manganese phthalocyanine; 1,4,8,11,15,18,22,25-octamethoxybutanoate copper phthalocyanine; 1,4,8,11,15,18,22,25-octamethoxybutanoate zinc phthalocyanine were investigated by infrared,The spectrum properties of four novel 1,4,8,11,15,18,22,25-octaoxybutyl copper phthalocyanine; 1,4,8,11,15,18,22,25-octamethoxybutanoate manganese phthalocyanine; 1,4,8,11,15,18,22,25-octamethoxybutanoate copper phthalocyanine; 1,4,8,11,15,18,22,25-octamethoxybutanoate zinc phthalocyanine were investigated by infrared, fluorescence and UV-visible spectrum in the the paper. There is no rule in the infrared spectrum of these octa-substituted phthalocyanines. The orders of the Q band, B band and Pc dimer band are different among the above Octa-substituted Phthalocyanines in the UV and fluorescence spectra. The reason is related to the interaction between the ligand and the central metal of these octa-substituted phthalocyanines..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2171 (2011)
Spectrum Research on Metamorphic and Deformation of Tectonically Deformed Coals
LI Xiao-shi, JU Yi-wen, HOU Quan-lin, and LIN Hong
The structural and compositive evolution of tectonically deformed coals (TDCs) and their influencing factors were investigated and analyzed in detail through Fourier transform infrared spectroscopy (FTIR) and laser Raman spectra analysis. The TDC samples (0.7%<Ro, max<3.1%) were collected from Huaibei coalfield wThe structural and compositive evolution of tectonically deformed coals (TDCs) and their influencing factors were investigated and analyzed in detail through Fourier transform infrared spectroscopy (FTIR) and laser Raman spectra analysis. The TDC samples (0.7%
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2176 (2011)
Spectroscopic Study on the Energy Transfer Effect in Sm3+/Eu3+ Codoped Tetragonal LaOF Nanocrystals System
FU Zhen-xing, ZHENG Hai-rong, and LIU Bi-rui
The powder samples of Sm3+/Eu3+co-doped in LaOF nanocrystals were synthesized by using a hydrothermal-sintering technique. The characterization results of XRD and TEM suggests that the structure of the nanocrystals is tetragonal, and its size is between 60～80 nm. Using 442 nm laser to pump the LaOF∶Sm3+/Eu3+ nanocrystaThe powder samples of Sm3+/Eu3+co-doped in LaOF nanocrystals were synthesized by using a hydrothermal-sintering technique. The characterization results of XRD and TEM suggests that the structure of the nanocrystals is tetragonal, and its size is between 60～80 nm. Using 442 nm laser to pump the LaOF∶Sm3+/Eu3+ nanocrystals samples, the energy transfer effect from Sm3+ ions to Eu3+ ions was completed, and the fluorescence emissions originating from the 5D0 level of Eu3+ were observed. The luminescence properties of the LaOF∶Sm3+/Eu3+ nanocrystals system were analyzed with a spectroscopic method, and the mechanism and dynamic process of the energy transfer were explored. It was found that the efficiency of the energy transfer increase with the increase in the concentration of Eu3+ ions and the size of nanocrystals..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2183 (2011)
Fresh and Frozen-Thawed Meat Discrimination Based on FISS Imaging Spectral Data
ZHANG Xue-wen, ZHANG Li-fu, HUANG Chang-ping, ZHENG Lan-fen, and TONG Qing-xi
In the present paper, a self-developed Field imaging spectrometer system (FISS) was used to detect whether pork has been frozen and thawed. The preservation time of fresh pork has also been identified. Fresh and frozen-thawed pork was scanned and imaged and hyperspectral image cubes were acquired using FISS. To eliminaIn the present paper, a self-developed Field imaging spectrometer system (FISS) was used to detect whether pork has been frozen and thawed. The preservation time of fresh pork has also been identified. Fresh and frozen-thawed pork was scanned and imaged and hyperspectral image cubes were acquired using FISS. To eliminate high-frequency random noise and baseline offset and improve the multi-collinearity, all samples were preprocessed by MNF (Minimum noise fraction) transform and first derivative. Multiple analysis models were built by using Wilks’ lambda stepwise method to select proper wavelengths. Fisher LDA (linear discriminant analysis) was performed to discriminate fresh and frozen-thawed pork. Eight selected bands gave 99% correct results of fresh or frozen-thawed pork samples. For the freshness by the day, classification accuracy reached 98% with 6 selected bands, while for the freshness by the hour, classification accuracy reached 93.6% with all 28 selected bands. The results showed that FISS might be used as a screening method to identify the quality of meat..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2187 (2011)
Synthesis, Spectroscopy and Photocatalytic Activity of ⅡB Elements Substituted Tungstoborate Heteropoly Complexes
GAO Li-hua, WANG Yi-bo, and BAI Li-jie
The Keggin ⅡB element-monosubstitiuted heteropoly compounds with the stoichiometry of K7［BW11O39M(H2O)］ (M=Zn, Cd) were prepared by one-pot method and characterizated via elemental analyses, FTIR, UV and XRD. The photocatalytic activity of K7［BW11O39M(H2O)］ was tested vis degradation of the model molecule, methyl red (The Keggin ⅡB element-monosubstitiuted heteropoly compounds with the stoichiometry of K7［BW11O39M(H2O)］ (M=Zn, Cd) were prepared by one-pot method and characterizated via elemental analyses, FTIR, UV and XRD. The photocatalytic activity of K7［BW11O39M(H2O)］ was tested vis degradation of the model molecule, methyl red (MR). After 60 min irradiation in the presence of K7［BW11O39M(H2O)］ (20 mg·L-1), the degradation rate of an aqueous MR (25 μmol·L-1, pH 2) got to 95%..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2191 (2011)
Characteristics of Thermal Infrared Hyperspectra and Prediction of Sand Content of Sandy Soil
HUANG Qi-ting, SHI Zhou, PAN Gui-ying, ZHOU Lian-qing, and JI Wen-jun
To explore the potential of thermal infrared hyperspecra for retrieving sand content in soil, the sandy soil was measured using a 102F Fourier Transform Infrared Spectroradiometer (FTIR), and the characteristics of sandy soil’s emissivity spectra were discussed based on correlation analysis and principal component analTo explore the potential of thermal infrared hyperspecra for retrieving sand content in soil, the sandy soil was measured using a 102F Fourier Transform Infrared Spectroradiometer (FTIR), and the characteristics of sandy soil’s emissivity spectra were discussed based on correlation analysis and principal component analysis. Moreover, the sand contents were predicted using two modeling methods: Partial least squares regression (PLSR) and principal component regression (PCR). The results show that the Reststrahlen feature(RF) of SiO2 is obvious in the emissivity spectra of sandy soil with two large asymmetrical absorption troughs near 8.13 and 9.17 μm and two small troughs in the region of 12～13 μm. Soil emissivity becomes lower when sand content increases, this trend is more evident especially in the regions of 8～9.5 μm and 9.5～10.4 μm of which correlation coefficients are above 0.65 and 0.5 respectively, and these two regions can account for 84.07% of total emissivity variance. Predictive precision varies significantly when sand content is predicted by different modeling methods or spectral variables. The PLSR model can achieve the highest predictive precision by using first-order derivative spectra, and it’s RMSE of modeling and prediction is 0.45 and 0.53 respectively, and the R2, 0.990 7 and 0.983 6, which means that the thermal hyperspectra has promising potential for retrieving sand content in soil..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2195 (2011)
Weight Spectral Angle Mapper (WSAM) Method for Hyperspectral Mineral Mapping
HE Zhong-hai, and HE Bin-bin
On the basis of analyzing the deficiency of spectral angle mapper (SAM), an improved similarity measure called weight SAM (WSAM) is proposed in the present paper. The fundamental idea is to set a weight in the “difference range” to increase the discriminability between the similar minerals. When we distinguish some kinOn the basis of analyzing the deficiency of spectral angle mapper (SAM), an improved similarity measure called weight SAM (WSAM) is proposed in the present paper. The fundamental idea is to set a weight in the “difference range” to increase the discriminability between the similar minerals. When we distinguish some kind of mineral, the authors can find the “difference range”, in which the difference in spectral feature between the similar mineral spectrum and the reference spectrum is huge, and gives weight k to the spectrum in this range to reduce the similarity and increase the discriminability between similar minerals. The experiment results of spectra and AVIRIS data indicate that the WSAM method reduces the similarity of target mineral and its similar mineral and increases our ability of visual interpretation..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2200 (2011)
Spectroscopic Studies on the Relationship Between Heat Treatment Process and Immunogenicity of β-Lactoglobulin in Milk
WU Xu-li, ZHU Qian-qian, CHENG Xiao-juan, XU Hong, LIU Zhi-gang, and WU Hui
The thermal denaturation of β-lactoglobulin of milk was investigated by using DSC, circular dichroism spectra, and fluorescence spectra systematically. And its corresponding immunogenicity was tested with ELISA experiments. In addition, bioinformatics methods were also used to explain the spectral characteristics and iThe thermal denaturation of β-lactoglobulin of milk was investigated by using DSC, circular dichroism spectra, and fluorescence spectra systematically. And its corresponding immunogenicity was tested with ELISA experiments. In addition, bioinformatics methods were also used to explain the spectral characteristics and its corresponding immunogenic change, analyze the conformational changes of the protein during thermal denaturation, and discuss the relationship between conformational change of β-lactoglobulin caused by heat and immunogenic change. Results from this study should be useful to the establishment of a spectral method examining the extent of thermal denaturation of the food allergen, and be helpful to the understanding of the mechanism of immunogenic change of food allergen treated by heat..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2205 (2011)
Mechanism Study of Fluoride Adsorption by Hydrous Metal Oxides
GUO Hui-chao, LI Wen-jun, CHANG Zhi-dong, WANG Huan-ying, and ZHOU Yue
Hydrous oxides of cerium, aluminum, nickel and copper were prepared by alkaline precipitation method. Langmuir adsorption isotherm was studied and specific surface area was measured by BET method through N2 adsorption-desorption process. IR characterization of hydrous metal oxides before and after fluoride adsorption wHydrous oxides of cerium, aluminum, nickel and copper were prepared by alkaline precipitation method. Langmuir adsorption isotherm was studied and specific surface area was measured by BET method through N2 adsorption-desorption process. IR characterization of hydrous metal oxides before and after fluoride adsorption was also studied. Results show that different hydrous metal oxides have different specific surface areas and their pore size distributions also are not all the same. Adsorption capacity is not directly dependent on the specific surface area. Isotherm study indicates that the adsorption follows Langmuir model and shows the feature of monolayer adsorption. IR study before and after fluoride adsorption shows that different hydrous metal oxides have similar adsorption sites in the same IR region as well as adsorption sites in the different IR region. The comprehensive interaction of these adsorption sites with fluoride ions results in the different adsorption capacity of different hydrous metal oxides..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2210 (2011)
Study on the Estrogen Derivative Marked by CdTe Quantum Dots
ZHONG Wen-ying, ZHANG Cui, XU Guo-feng, YAN Ming, and XU Dan-ke
Abstract: Water-soluble CdTe quantum dots (QDs) stabilized by thioglycolic acid (TGA) with high quantum yield were synthesized. And the small biomolecule 17β-amino-estradiol was marked successfully by CdTe QDs. The analysis of UV-Vis spectroscopy, fluorescence spectroscopy, infrared spectroscopy and inverted microscopeAbstract: Water-soluble CdTe quantum dots (QDs) stabilized by thioglycolic acid (TGA) with high quantum yield were synthesized. And the small biomolecule 17β-amino-estradiol was marked successfully by CdTe QDs. The analysis of UV-Vis spectroscopy, fluorescence spectroscopy, infrared spectroscopy and inverted microscope photographs showed that the surface carboxyl of CdTe quantum dots conjugated with the amino of 17β-amino-estradiol through the activation of N-hydroxysuccinimide. 17β-amino-estradiol marked by CdTe QDs successfully provided an experimental basis for new drug screening model..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2215 (2011)
Study on the Structure of Defatted Wheat Germ Protein Isolate under Ultrasonic Treatment
LIU Bin, MA Hai-le, LI Shu-jun, TIAN Wan-min, and WU Ben-gang
The structure changes of defatted wheat germ protein Isolate (DWGP) treated by ultrasonic was determined by FTIR and fluorescence spectra, and the effect of its structure changes on the high-efficient enzymatic hydrolysis was studied. Research showed that the efficiency of hydrolysate could be improved by ultrasonic trThe structure changes of defatted wheat germ protein Isolate (DWGP) treated by ultrasonic was determined by FTIR and fluorescence spectra, and the effect of its structure changes on the high-efficient enzymatic hydrolysis was studied. Research showed that the efficiency of hydrolysate could be improved by ultrasonic treatment. Compared with control group, inhibitory activity of the hydrolysate was increased by 23.96% after the treatment of 600 W for 10 min. The fluorescence intensity of DWGP after ultrasonic treatment was found discovered to be changed. An appropriate ultrasonic treatment can unfold the protein molecule and make the chromogenic groups uncovered, which contribute to the acquirement of the higher-activity inhibitory peptide. The effects of various ultrasonic power and time on the secondary structure of DWGP were quantitatively determined via analysis of the amide Ⅰ changes of infrared spectra using curve fitting method. Content of β-sheet was decreased and β-turn was increased after ultrasonic treatment, which could be the main factor to make the prepared inhibitory peptides high efficient. The results provide a theoretical basis for the mechanism research of enzymatic hydrolysis of ultrasonic treated protein..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2220 (2011)
Snow Cover Monitoring Method by Using HJ-1 Satellite Data
WANG Li-tao, ZHOU Yi, ZHOU Qiang, WANG Shi-xin, and YAN Fu-li
Environment and Disasters Monitoring Microsatellite Constellation with high spatial resolution, high temporal resolution and high spectral resolution characteristics was put forward by China. HJ-1B satellite, one of the first two small optical satellites, had a CCD camera and an infrared camera, which would provide an Environment and Disasters Monitoring Microsatellite Constellation with high spatial resolution, high temporal resolution and high spectral resolution characteristics was put forward by China. HJ-1B satellite, one of the first two small optical satellites, had a CCD camera and an infrared camera, which would provide an important new data source for snow monitoring. In the present paper, through analyzing the sensor and data characteristics of HJ-1B, we proposed a new infrared normalized difference snow index (INDSI) referring to the traditional normalized difference snow index (NDSI). The accuracy of these two automatic snow recognition methods was estimated based on a supervised classification method. The accuracy of the traditional NDSI method was 97.761 9% while that of the new INDSI method was 98.617 1%..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2226 (2011)
Retrieve of Red Tide Distributions from MODIS Data Based on the Characteristics of Water Spectrum
QIU Zhong-feng, CUI Ting-wei, and HE Yi-jun
After comparing the spectral differences between red tide water and normal water, we developed a method to retrieve red tide distributions from MODIS data based on the characteristics of red tide water spectrum. The authors used the 119 series of in situ observations to validate the method and found that only one obserAfter comparing the spectral differences between red tide water and normal water, we developed a method to retrieve red tide distributions from MODIS data based on the characteristics of red tide water spectrum. The authors used the 119 series of in situ observations to validate the method and found that only one observation has not been detected correctly. The authors then applied this method to MODIS data on April 4, 2005. In the research areas three locations of red tide water were apparently detected with the total areas about 2 000 km2. The retrieved red tide distributions are in good agreement with the distributions of high chlorophyll a concentrations. The research suggests that the method is available to eliminating the influence of suspended sediments and can be used to retrieve the locations and areas of red tide water..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2233 (2011)
Atmospheric Correction of HJ-1 CCD Data for Water Imagery Based on Dark Object Model
ZHOU Li-guo, MA Wei-chun, GU Wan-hua, and HUAI Hong-yan
The CCD multi-band data of HJ-1A has great potential in inland water quality monitoring, but the precision of atmospheric correction is a premise and necessary procedure for its application. In this paper, a method based on dark pixel for water-leaving radiance retrieving is proposed. Beside the Rayleigh scattering, thThe CCD multi-band data of HJ-1A has great potential in inland water quality monitoring, but the precision of atmospheric correction is a premise and necessary procedure for its application. In this paper, a method based on dark pixel for water-leaving radiance retrieving is proposed. Beside the Rayleigh scattering, the aerosol scattering is important to atmospheric correction, the water quality of inland lakes always are case Ⅱ water and the value of water leaving radiance is not zero. So the synchronous MODIS shortwave infrared data was used to obtain the aerosol parameters, and in virtue of the characteristic that aerosol scattering is relative stabilized in 560 nm, the water-leaving radiance for each visible and near infrared band were retrieved and normalized, accordingly the remotely sensed reflectance of water was computed. The results show that the atmospheric correction method based on the imagery itself is more effective for the retrieval of water parameters for HJ-1A CCD data..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2238 (2011)
Solid Phase Extraction and Determination of Nickel in Water Samples by Using Novel Thiol-Containing Sulfonamide Polymeric Resin and Atomic Absorption Spectrophotometer
Nagihan M Karaaslan, B Filiz Senkal, Cigdem Er, Halim Avci, and Mehmet Yaman
Interest in preconcentration techniques for the determination of metals at ultratrace levels still continues increasingly because of some disadvantages of flameless atomic absorption spectrometry as well as the high costs of other sensitive methods in compared to flame atomic absorption spectrometry. In this study, thiInterest in preconcentration techniques for the determination of metals at ultratrace levels still continues increasingly because of some disadvantages of flameless atomic absorption spectrometry as well as the high costs of other sensitive methods in compared to flame atomic absorption spectrometry. In this study, thiol-containing sulfonamide resin was synthesized, characterized and applied as a new sorption material for solid phase extraction of nickel in drinking water samples. After preconcentration procedure, flame atomic absorption spectrometry was used for determinations. Optimum parameters were found to be pH=3.2, contact time=20 min and eluate volume=3 mL. The limit of detection was found to be 0.75 ng·mL-1. The synthesized resin exhibits the superiority in compared to the other adsorption reagents because of the fact that there is no necessity of any complexing reagent, high sorption capacity as well as the relatively fast extraction rate. The Ni concentrations in the studied 21 kind of water samples were found to be in the range of BDL-4.0 ng·mL-1..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2243 (2011)
Laser Ablation and Fast Pulse Discharge Plasma Spectroscopy Analysis of Sn in Soil
LI Ke-xue, ZHOU Wei-dong, SHEN Qin-mei, ZHEN Yi, LI Xia-fen, QIAN Hui-guo, and SHAO Jie
A developing technique, laser ablation and fast pulse discharge plasma spectroscopy technique (LA-FPDPS), was used for the first time to analyze the Sn concentration in soil. The peak intensity of Sn (284.0 nm) line from soil plasma emission was greatly enhanced in comparison with using the traditional single pulse (SPA developing technique, laser ablation and fast pulse discharge plasma spectroscopy technique (LA-FPDPS), was used for the first time to analyze the Sn concentration in soil. The peak intensity of Sn (284.0 nm) line from soil plasma emission was greatly enhanced in comparison with using the traditional single pulse (SP) LIBS system. Using the technique, calibration curve of Sn in soil was derived. The limit of detection (LOD) for Sn in soil was reduced to be 0.16 μg·g-1. The value is significantly improved compared with the results reported in literature when using LIBS technique, which usually was between 8.2 to 54 μg·g-1 depending on the experimental condition, indicating that this technique possibly will be useful for rapid quantitative elemental analysis in soil..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2249 (2011)
Determination of Nano-Silver Spatiotemporal Distribution in Cut Gerbera Flowers by ICP-AES
Lv Pei-tao, HUANG Xin-min, LU Yi-min, LIU Ji-ping, ZHANG Zhao-qi, and HE Sheng-gen
The spatiotemporal distribution of nano-silver in cut gerbera (Gerbera hybrida cv. Crossfire) flowers were determined by inductively coupled plasma-atomic emission spectrometry technique (ICP-AES). The relative standard deviations of this method were between 0.14% and 2.89%, and the recovery ratio obtained by standard The spatiotemporal distribution of nano-silver in cut gerbera (Gerbera hybrida cv. Crossfire) flowers were determined by inductively coupled plasma-atomic emission spectrometry technique (ICP-AES). The relative standard deviations of this method were between 0.14% and 2.89%, and the recovery ratio obtained by standard addition method ranged from 93.33% to 106.67%. The method was proved to be simple, rapid, reliable and highly sensitive, which can meet the demands of actua1 sample analysis. The experimental results also showed that Ag could be found in the basal stem end, upper stem end and petal of the cut gerbera flowers treated in nano-silver solution of 5 mg· L-1 for 24 h and thereafter placed in distilled water. However, the Ag content in basal stem ends was much higher than those in upper stem ends and petals. The results indicated that nano-silver particles could enter into the flower stems through the cuts of stem ends and then moved to different parts of the cut gerbera flowers, but most of them located in the basal stem ends during the vase period. The fact that Ag was centred in basal stem end implied that the positive preservation effects of nano-silver on cut gerbera flowers is related to its strong and sustainable antiseptic action in the stem ends of cut flowers. The above results provide a reliable method for the determination of nano-silver and theoretical basis for its futher research and application in the preservation of cut flowers..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2253 (2011)
Comparative Study on Five Pretreatment Methods for ICP-OES Determination of Mineral Elements in Rosa rugosa
ZHAO Ning, YANG Bin, DUAN Yu-cen, and LEI Ran
Five different pretreatment methods, including dry ashing and microwave digestion with four acid systems (HNO3+H2O2, HNO3+H2O2+HF, HNO3+HClO4 and HNO3+HClO4+HF), were employed for digestion of the samples of Rosa rugosa. Nine major and trace elements were determined using ICP-OES method. The addition standard recovery Five different pretreatment methods, including dry ashing and microwave digestion with four acid systems (HNO3+H2O2, HNO3+H2O2+HF, HNO3+HClO4 and HNO3+HClO4+HF), were employed for digestion of the samples of Rosa rugosa. Nine major and trace elements were determined using ICP-OES method. The addition standard recovery rates indicate that, with the system of HNO3+HClO4, better results can be obtained for most of the determined elements. With this method, except for Fe, the recovery rates are in the range of 95.4%～104.6%. For Fe, higher recovery rate (99%) was obtained with HNO3+H2O2+HF system..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2256 (2011)
Realtime Analysis of Volatile Organic Compounds in Source Water by Membrane Inlet/Time-of-Flight Mass Spectrometry
YU Bo-fan, WEN Li-li, SONG Yong-hui, LIU Hong-liang, LI Hai-yang, CUI Hua-peng, XIE Bin-yu, and SI Ji-hong
To establish an early-warning system for source water pollution accident, a membrane inlet / time-of-flight mass spectrometry technology was applied to a series of pollution scenarios as an online monitoring method for typical volatile organic compounds such as BTEX (benzene, toluene, ethylbenzene and xylene), substituTo establish an early-warning system for source water pollution accident, a membrane inlet / time-of-flight mass spectrometry technology was applied to a series of pollution scenarios as an online monitoring method for typical volatile organic compounds such as BTEX (benzene, toluene, ethylbenzene and xylene), substituted benzenes, and halogenated aliphatic hydrocarbons. It was shown that this technology can adequately meet the requirements of realtime analysis with short response time to the target organic pollutants (30～70 s for BTEX and 30 s for halogenated aliphatic hydrocarbons) in a linear detecting range of 3～4 magnitudes; the detection limits of BTEX and chlorobenzene were less than 10 μg·L-1. The results of 52 simulated water pollution accidents in a 30-days’ continuous monitoring indicated that the monitoring system was stable with the relative standard deviation less than 5%; the accuracy was acceptable and could be reduced to within 10% by periodical calibrations. Membrane inlet/time-of-flight mass spectrometry technology was proven to be available for the remote monitoring and early-warning of source water pollution accident..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2259 (2011)
The Property Changes of Urine Crystallites of Calcium Oxalate Stone Formers before and after Taking Medicine
LI Jun-jun, HOU Shan-hua, XIA Zhi-yue, and OUYANG Jian-ming
The property changes of urine crystallites of six cases of calcium oxalate stone formers before and after taking medicine were comparatively studied using X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, nanoparticle size analyzer, and transmission electron microscopy (TEM). The results showed tThe property changes of urine crystallites of six cases of calcium oxalate stone formers before and after taking medicine were comparatively studied using X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, nanoparticle size analyzer, and transmission electron microscopy (TEM). The results showed that the urinary pH increases after taking medicine (before taking 5.87±0.51, after taking 6.23±0.74.) Before taking medicine the main components of urine crystallites were uric acid, calcium oxalate monohydrate (COM) and biphosphate. The types and quantities of urine crystallites after taking medicine were less than that of before. The average size of urine crystallite before taking medicine was (579±326) nm, and it reduced to (404±338) nm after taking medicine. After taking medicine the zeta potential was also decreased to (-7.29±4.16) mV from (-4.28±2.55) mV. The decrease in zeta potential is beneficial to preventing urinary crystallites deposition. The edges and corners of urine crystallite were sharp with significant aggregation before taking medicine, while they became blunt and less aggregation after taking medicine. The analysis of the property changes of urine crystallites of calcium oxalate stone patients before and after taking medicine by using modern equipments has important clinical significance to the clinical prevention and treatment of urinary stones..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2263 (2011)
XRD, FTIR and Thermoluminescence Spectra of Different Types of Urinary Stones
YANG Jin, HE Jie-yu, and OUYANG Jian-ming
Using thermoluminescence spectrometer, X-ray diffraction and Fourier transform infrared spectroscopy, the chemical compositions of four types of kidney stones were investigated. They are calcium oxalate, uric acid, calcium phosphate and magnesium ammonium phosphate calculi (struvite). Experimental results showed that iUsing thermoluminescence spectrometer, X-ray diffraction and Fourier transform infrared spectroscopy, the chemical compositions of four types of kidney stones were investigated. They are calcium oxalate, uric acid, calcium phosphate and magnesium ammonium phosphate calculi (struvite). Experimental results showed that in the 305 cases of stones, calculi oxalate stones were found to account for 63%, uric acid stones 22%, calcium phosphate stones 8%, struvite 5%, and the stones with other compositions 2%. There were significant differences in the thermoluminescence spectra among the 4 types of urinary stones, which can provide an important basis for the clinic diagnosis of urinary stone types..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2268 (2011)
Standard Sample Preparation Method for Quick Determination of Trace Elements in Plastic
YAO Wen-qing, ZONG Rui-long, and ZHU Yong-fa
Reference sample was prepared by masterbatch method, containing heavy metals with known concentration of electronic information products (plastic), the repeatability and precision were determined, and reference sample preparation procedures were established. X-Ray fluorescence spectroscopy (XRF) analysis method was useReference sample was prepared by masterbatch method, containing heavy metals with known concentration of electronic information products (plastic), the repeatability and precision were determined, and reference sample preparation procedures were established. X-Ray fluorescence spectroscopy (XRF) analysis method was used to determine the repeatability and uncertainty in the analysis of the sample of heavy metals and bromine element. The working curve and the metrical methods for the reference sample were carried out. The results showed that the use of the method in the 200～2 000 mg·kg-1 concentration range for Hg, Pb, Cr and Br elements, and in the 20～200 mg·kg-1 range for Cd elements, exhibited a very good linear relationship, and the repeatability of analysis methods for six times is good. In testing the circuit board ICB288G and ICB288 from the Mitsubishi Heavy Industry Company, results agreed with the recommended values..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2274 (2011)
Data Mining of Cataclysmic Variables Candidates in Massive Spectra
JIANG Bin, LUO A-li, and ZHAO Yong-heng
An automatic and efficient method for LAMOST’s massive spectral data reduction is presented in this paper. The identified cataclysmic variables were selected as templates to construct the feature space by PCA (the principal component analysis）, and most of the non-candidates were excluded by the method using support veAn automatic and efficient method for LAMOST’s massive spectral data reduction is presented in this paper. The identified cataclysmic variables were selected as templates to construct the feature space by PCA (the principal component analysis）, and most of the non-candidates were excluded by the method using support vector machine. Template matching strategy was used to identify the final candidates which were analyzed to complement the templates as feedback. Fifty eight new CVs candidates were found in the experiment, showing that our approach to finding special celestial bodies can be practical in LAMOST..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2278 (2011)
Hyperspectral Image Compression Technology Research Based on EZW
WEI Jun-xia, XIANGLI Bin, DUAN Xiao-feng, XU Zhao-hui, and XUE Li-jun
Along with the development of hyperspectral remote sensing technology, hyperspectral imaging technology has been applied in the aspect of aviation and spaceflight, which is different from multispectral imaging, and with the band width of nanoscale spectral imaging the target continuously,the image resolution is very hiAlong with the development of hyperspectral remote sensing technology, hyperspectral imaging technology has been applied in the aspect of aviation and spaceflight, which is different from multispectral imaging, and with the band width of nanoscale spectral imaging the target continuously,the image resolution is very high. However, with the increasing number of band, spectral data quantity will be more and more, and these data storage and transmission is the problem that the authors must face. Along with the development of wavelet compression technology, in field of image compression, many people adopted and improved EZW, the present paper used the method in hyperspectral spatial dimension compression, but does not involved the spectrum dimension compression. From hyperspectral image compression reconstruction results, whether from the peak signal-to-noise ratio (PSNR) and spectral curve or from the subjective comparison of source and reconstruction image, the effect is well. If the first compression of image from spectrum dimension is made, then compression on space dimension, the authors believe the effect will be better..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2283 (2011)
A New Hyperspectral Image Compression Method Combined with Subspace Partition and Multi-Inter-Spectral Prediction
GAO Wen, ZHU Ming, TIAN Run-lan, and TANG Yang
Because of their rich and complex texture, multi-band and high spectral resolution, hyperspectral images are widely used in military, marine, agriculture and other aspects; however, their huge data also brings many troubles. Currently, there’re almost three types of the hyper-spectral image compression methods: the metBecause of their rich and complex texture, multi-band and high spectral resolution, hyperspectral images are widely used in military, marine, agriculture and other aspects; however, their huge data also brings many troubles. Currently, there’re almost three types of the hyper-spectral image compression methods: the method based on transform, prediction and vector quantization, among which, the method based on prediction has the advantages such as easy implement and higher compression ratio, then it’s widely used. In the present paper, features of hyperspectral images are analyzed first in detail, then inter-spectral prediction algorithm is improved, and a new scheme which consists of subspace partition and multi-inter-spectral prediction is proposed, and finally, the experiments show that the program is effective..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2287 (2011)
Development and Test of a Wheat Chlorophyll, Nitrogen and Water Content Meter
YU Bo, SUN Ming, HAN Shu-qing, and XIA Jin-wen
A portable meter was developed which can detect chlorophyll, nitrogen and moisture content of wheat leaf simultaneously, and can supply enough data for guiding fertilization and irrigation. This meter is composed of light path and electronic circuit. And this meter uses 660, 940 and 1 450 nm LED together with narrow baA portable meter was developed which can detect chlorophyll, nitrogen and moisture content of wheat leaf simultaneously, and can supply enough data for guiding fertilization and irrigation. This meter is composed of light path and electronic circuit. And this meter uses 660, 940 and 1 450 nm LED together with narrow band filters as the active light source. The hardware circuit consists of micro-controller, LED drive circuit, detector, communication circuit, keyboard and LCD circuit. The meter was tested in the field and performed well with good repeatability and accuracy. The relative errors of chlorophyll and nitrogen test were about 10%, relative error for water content was 4 %. The coefficients of variation of the three indices were all below 1.5%. All of these prove that the meter can be applied under the field condition to guide the wheat production..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2294 (2011)
Improving Laser Center Wavelength Detection Accuracy Based on Multi-Level Combination Prisms
LIU Xiao-dong, and ZHANG Zhi-jie
In order to improve the spectral resolution of birefringence prism under the conditions of ensuring the quality of interference fringes image, the system used multi-level combination prisms and designed the method of interferometer fringes splice. According to calculation of the interferometer fringes intensity of multIn order to improve the spectral resolution of birefringence prism under the conditions of ensuring the quality of interference fringes image, the system used multi-level combination prisms and designed the method of interferometer fringes splice. According to calculation of the interferometer fringes intensity of multi-level combination prisms, the optical path difference function and the spectrum resolution, the present paper analyzed that the least spectrum resolution is 2.875 cm-1 in multi-level combination prisms of four prisms structure. The method of interferometer fringes splice was designed to splice the section interferometer fringes, and in experiment the size of multi-level combination prisms is 30 mm×28 mm×10 mm. The standard 635 nm laser for getting the interferometer fringes was dealed with. Experimental data show that the detection spectrum distribution of the 635.0 nm laser was distorted by the direct splicing of the interference fringes, while the detection spectrum distribution of the 635.0nm laser was consistent with the standard spectrum by the method of interferometer fringes splice. So the method can effectively avoid spectrum distortion by interferometer fringes splice in multi-level combination prisms..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 2298 (2011)
[in Chinese]
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 8, 1 (2011)
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