Journals >Spectroscopy and Spectral Analysis
Contents
2011
Volume: 31 Issue 1
65 Article(s)
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Research Article
Coupling Liquid Phase Electrochemistry with Nuclear Magnetic Resonance Spectroscopy and Its Applications
NI Zu-rong, CUI Xiao-hong, SUN Shi-gang, and CHEN Zhong
The combination of liquid nuclear magnetic resonance spectroscopy (NMR) and electrochemistry (EC) is a new technique with promising prospect which provides novel, exciting, and crucial insights into the processes near or on the electrode surface at a molecular or atomic level. The development of in situ EC-NMR spectrosThe combination of liquid nuclear magnetic resonance spectroscopy (NMR) and electrochemistry (EC) is a new technique with promising prospect which provides novel, exciting, and crucial insights into the processes near or on the electrode surface at a molecular or atomic level. The development of in situ EC-NMR spectroscopy with flow or static electrolysis was summarized, the structures of the electrolysis cell and the characteristics of the NMR spectra were analyzed, and the feature of the in situ EC-NMR spectroscopy in practice was described in detail. The electrolysis electrode located at radio-frequency detection area of the NMR spectrometer reduced homogeneity of the magnetic field. Furthermore, the electrolysis current results in broadened spectral lines and loss of resolution. The working electrode consisting of a thin metal film and the electrolysis current parallel to the static magnetic field can overcome such shortcomings. Besides, several high-resolution methods in inhomogeneous fields were discussed and compared, such as intramolecular multiple quantum coherences, nutation echos, intermolecular nuclear Overhauser effects, and intermolecular multiple quantum coherences..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 1 (2011)
[in Chinese]
[in Chinese]
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 1 (2011)
Enhanced Voc in Photovoltaic Cell by Electrodeposited Polythiophene Thin Film
WANG Yun, XIAO Li-xin, CHEN Zhi-jian, QU Bo, and GONG Qi-huang
Poly(3-hexylthiophene) (P3HT) thin films were electrochemically deposited directly on indium tin oxide (ITO)/poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT∶PSS) substrates. Its optical absorption peak is located at about 410 nm and tailing to 610 nm, corresponding to 2.04 eV of bandgap. Its highest occuPoly(3-hexylthiophene) (P3HT) thin films were electrochemically deposited directly on indium tin oxide (ITO)/poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT∶PSS) substrates. Its optical absorption peak is located at about 410 nm and tailing to 610 nm, corresponding to 2.04 eV of bandgap. Its highest occupied molecular orbital (HOMO) energy is -5.21 eV, while the HOMO energy of the chemically synthesized P3HT is -5.02 eV. The lower HOMO energy of the electrodeposited P3HT may be attributed to the enhancement of regularity. The morphology of the P3HT thin film characterized by atomic force microscopy (AFM) indicates that the molecules contact firmly. The cyclic voltammetry results show that its electrochemical property is stable. theauthors prepared photovoltaic cell with the P3HT and ［6,6］-phenyl-C61-butyric acid methyl ester (PCBM) as the active layer. Because of the lower HOMO of the electrodeposited P3HT, the open circuit voltage (Voc) of the device is up to 0.76 V, indicating a new way to enhance the Voc of the organic photovoltaic cells..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 7 (2011)
FAIMS of Trace Volatile Organic Compounds
LI Zhuang, LIN Bing-tao, KONG De-yi, CHEN Chi-lai, CHENG Yu-peng, WANG Huan-qin, and MEI Tao
FAIMS is a fast and high sensitive technique for detecting trace volatile organic compounds. Spectra of acetone, benzene and toluene were obtained on a homemade high-field asymmetric waveform ion mobility spectrometer and they can be easily separated in the spectra. Three xylene isomeric compounds were also successfullFAIMS is a fast and high sensitive technique for detecting trace volatile organic compounds. Spectra of acetone, benzene and toluene were obtained on a homemade high-field asymmetric waveform ion mobility spectrometer and they can be easily separated in the spectra. Three xylene isomeric compounds were also successfully separated in FAIMS. Effect of carrier gas flow rate on the ion intensity was analyzed, and the optimal flow rate of carrier gas was 220 L·h-1 which can be used for the optimization of FAIMS instrument. The detection limit for acetone is 100 ng·L-1 that is an order of magnitude lower than the foreign traditional IMS..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 12 (2011)
A Noise Reduction Algorithm of Hyperspectral Imagery Using Double-Regularizing Terms Total Variation
LI Ting, CHEN Xiao-mei, CHEN Gang, XUE Bo, and NI Guo-qiang
In the present paper, an effective total variation denoising algorithm is proposed based on hyperspectral imagery noise characteristics. The new algorithm generalizes the classical total variation denoising algorithm for two-dimensional images to a three-dimensional formulation. Considering the fact that the noise of hIn the present paper, an effective total variation denoising algorithm is proposed based on hyperspectral imagery noise characteristics. The new algorithm generalizes the classical total variation denoising algorithm for two-dimensional images to a three-dimensional formulation. Considering the fact that the noise of hyperspectral imagery shows different characteristics in spatial domain and spectral domain respectively, the objective function of the proposed total variation algorithm is improved by utilizing double-regularizing terms (spatial term and spectral term) and separate regularization parameters respectively. Then, the new objective function is discretized via approximating the gradient of the regularizing terms by three orthogonal local differences, and further majorized by a convex quadratic function. Thus, noise in spatial and spectral domain could be removed independently by minimizing the majorizing function with a majorization-minimization (MM) based iteration. The performance of the proposed algorithm is experimented on a set of Hyperion imageries acquired in 2007. Experiment results show that, properly choosing the values of regularization parameters, the new algorithm has a similar improvement of signal-to-noise-ratio as minimum noise fraction (MNF) method and Savitzky-Golay filter, but a better performance in removing the indention and restoring the spectral absorption peaks..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 16 (2011)
Experimental Investigation on Micro-Hollow Cathode Sustained Discharge
XIA Guang-qing, and Nader Sadeghi
Based on micro-hollow cathode discharge (MHCD) as a plasma cathode, a second anode was added to the device for obtaining large volume and uniform plasma at high pressure. The discharge producing condition of MCSD was investigated in the experiments. And the rotational structures of the N2 first positive bands were analBased on micro-hollow cathode discharge (MHCD) as a plasma cathode, a second anode was added to the device for obtaining large volume and uniform plasma at high pressure. The discharge producing condition of MCSD was investigated in the experiments. And the rotational structures of the N2 first positive bands were analyzed with traces of nitrogen added in argon for the measurements of the gas temperature in the MCSD plume. The experimental results show that when the current of the plasma cathode exceeds the threshold, the large volume stable plasma is generated. The gas temperature in the plume is increased a little with increasing the current (0.5~4 mA) and is about 500 K at the pressure of 50 Torr..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 21 (2011)
Study on the n=5 Complex Transitions for Ions Nd -Sm ⅩⅤ in Cd Ⅰ Isoelectronic Sequence
DING Kai, MU Zhi-dong, and YE Shi-wang
The energy levels of the n=5 complex configuration 5s2, 5s5p, 5s5d and 5p2 were computed for Cd Ⅰ isoelectronic sequence ions from I Ⅵ to Sm ⅩⅤ by Hartree-Fock with relativistic corrections (HFR) method. By analyzing the variation of difference ΔE between energy levels calculated by HFR method and the experimental valuThe energy levels of the n=5 complex configuration 5s2, 5s5p, 5s5d and 5p2 were computed for Cd Ⅰ isoelectronic sequence ions from I Ⅵ to Sm ⅩⅤ by Hartree-Fock with relativistic corrections (HFR) method. By analyzing the variation of difference ΔE between energy levels calculated by HFR method and the experimental values with Zc along this isoelectronic sequence, the authors put forward a new fitting formula for generalized-least-square-fit (LSF) calculation. Using this formula and the FORTRAN programme designed by us, the energy levels of configurations mentioned above were calculated. The unknown energy levels of configuration 5s2, 5s5p, 5s5d and 5p2 for ions from Nd -Sm ⅩⅤ were predicted by extrapolation (or interpolation). Also, the wavelengths and HFR probabilities of transition 5s2—5s5p, 5s5p—5p2 and 5s5p—5s5d were computed. The calculated energy levels and wavelength results are in good agreement with corresponding experimental data reported in the references..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 25 (2011)
Application of Laser Raman Spectroscopy to Hydrogen Isotope Analysis
HUANG Gang, CAO Xiao-hua, and LONG Xing-gui
Analysis of laser Raman spectroscopy has turned into the efficient research method of substance structure and composition analysis. In the present paper, the principle of laser Raman spectroscopy and its characteristics of analysis method are introduced. Applicability of laser Raman spectroscopy to hydrogen isotope anaAnalysis of laser Raman spectroscopy has turned into the efficient research method of substance structure and composition analysis. In the present paper, the principle of laser Raman spectroscopy and its characteristics of analysis method are introduced. Applicability of laser Raman spectroscopy to hydrogen isotope analysis is analyzed. The analytical applications of laser Raman spectroscopy method in radiation reaction of tritium, hydrogen isotope examination and quantitative analysis are presented from reported literature..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 30 (2011)
Study on Colored Dissolved Organic Matter Concentration Retrieved from Landsat/TM Imagery at Taihu Lake
CHEN Jun, WANG Bao-jun, SUN Ji-hong, and FU Jun
At the lake ecosystem, the CDOM (colored dissolved organic matter) not only is an important source of nutrients, but also is major component of carbon cycle. Based on the fieldworks of water qualities experiments at Taihu lake, China, on 27 and 28 October, 2003, the present paper used the Landsat/TM imageries to study At the lake ecosystem, the CDOM (colored dissolved organic matter) not only is an important source of nutrients, but also is major component of carbon cycle. Based on the fieldworks of water qualities experiments at Taihu lake, China, on 27 and 28 October, 2003, the present paper used the Landsat/TM imageries to study and estimate the distribution pattern of CDOM concentration at Taihu lake. According to the study results, it was found that CDOM was a strong absorber at TM1 band, where there was a wave trough at that corresponding wavelength. Taking the reflectance at TM1 as a remote sensing parameter, the remote sensing technology could perfectly retrieval the CDOM concentration from the Landsat/TM imagery at TM1 band. Compared with the validation dataset at two stations, the mean bias between modeled prediction and in situ measurements was 0.922 mg·L-1, and the corresponding relative bias was 14.85%. Additionally, the retrieval results show that the spatial distribution of CDOM concentration was higher in the south and center of the lake, but lower in the east and west lake..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 34 (2011)
Vibrational Energy Transfer from Vibrational Levels of RbH(X 1Σ＋, ｖ＝0～2) to H2
SHEN Xiao-yan, WANG Shu-ying, LIU Jing, DAI Kang, and SHEN Yi-fan
The vibrational energy transfer from vibrational levels of RbH(X 1Σ＋, ｖ＝0～2) by collision with H2 was determined using the integrated time-resolved laser induced fluorescence (LIF) in a five-arm crossed heat-pipe oven. Rb-H2 mixture was irradiated with pulses of 696.4 nm radiation from a OPO laser, populating 6D state The vibrational energy transfer from vibrational levels of RbH(X 1Σ＋, ｖ＝0～2) by collision with H2 was determined using the integrated time-resolved laser induced fluorescence (LIF) in a five-arm crossed heat-pipe oven. Rb-H2 mixture was irradiated with pulses of 696.4 nm radiation from a OPO laser, populating 6D state by two-photon absorption. The vibrational levels of RbH(X 1Σ＋) generated in the reaction of Rb(6D) and H2 were detected by LIF technique. The nascent quantum state distributions of RbH were obtained when the delay time between the pump and probe laser was 20 ns. The nascent RbH product molecules were found to populate the lowest three vibrational (v=0, 1, 2) levels of the ground electronic state but could not be detected in any higher vibrational state. The integrated time-resolved LIF excited Ａ １Σ＋→Ｘ １Σ＋ system in the presence of H2 was recorded with delay time from 0 to 10 μs. The RbH signal of v=0, 1 levels first increased and then decreased on a larger time scale. RbH was created instantaneously then was quenched by collision and diffused. The rate equations for the population of the vibrational levels were given. The integrated profiles method permitted us to determine the rate coefficients for vibrational transfer of RbH(X 1Σ＋, ｖ＝0～2) by collision with H2. The rate coefficients for collisional transfer of RbH(X 1Σ＋) by collisions with H2 are(in units of 10-11 cm3·s-1) 3.4±0.8 and 2.8±0.6 for ｖ＝２→ｖ＝１ and ｖ＝１→ｖ＝０ respectively. The diffusion rates of v=0, 1, 2 are(in units of 105 s-1) 4.9±1.1, 1.0±0.3a nd 0.6±0.2, respectively. The experiment showed that vibrational relaxation from RbH(X 1Σ＋, ｖ＝0～2) was more efficient compared to that of other vibrational levels studied here..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 39 (2011)
Near-Infrared Fluorescence and Energy Transfer in Sr2SiO4∶Eu2+,Nd3+
YANG Li-li, WAN Wen-jiao, LI Jin-qing, and MENG Jian-xin
Sr2SiO4∶Eu2+, Nd3+ was synthesized by solid state synthesis method, and the sensitization of Nd3+ near-infrared luminescence by Eu2+ was investigated. The characteristic near-infrared luminescence of Nd3+ in Sr2SiO4 matrix was greatly enhanced by co-doping of Eu2+. The mechanism of energy transfer from Eu2+ to Nd3+ wasSr2SiO4∶Eu2+, Nd3+ was synthesized by solid state synthesis method, and the sensitization of Nd3+ near-infrared luminescence by Eu2+ was investigated. The characteristic near-infrared luminescence of Nd3+ in Sr2SiO4 matrix was greatly enhanced by co-doping of Eu2+. The mechanism of energy transfer from Eu2+ to Nd3+ was analyzed through investigation of fluorescence excitation and emission spectra, and fluorescence lifetime. Excited Eu2+(Ⅱ) transfers energy effectively to Nd3+ through non-radiative energy transfer process in Sr2SiO4, resulting in greatly enhanced near-infrared luminescence of Nd3+, while sensitization of Nd3+ by Eu2+(Ⅰ) was achieved by the way of Eu2+(Ⅱ)..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 43 (2011)
Simulation of Microcavity Organic Light Emitting Device with Two Kinds of Resonant Cavity Lengths
ZHANG Chun-yu, LU Jing-bin, WANG Cheng, and WANG Hong-jie
The resonant cavity length of microcavity influences the light emitting characteristics of microcavity organic light emitting device (MOLED) directly. According to the related calculation formula of microcavity device, when the lengths of microcavity are λ/2 and λ, the authors use transfer matrix method to simulate andThe resonant cavity length of microcavity influences the light emitting characteristics of microcavity organic light emitting device (MOLED) directly. According to the related calculation formula of microcavity device, when the lengths of microcavity are λ/2 and λ, the authors use transfer matrix method to simulate and compare with the functions of composite light emitting EL when exciton is in different positions of microcavity. The authors found that when the length of microcavity is λ/2, the peaks of luminous spectrum are all at the 520 nm, and the width of half-peaks are all 17 nm. The peak intensity and integral intensity are biggest when exciton is in the central area of microcavity. When the length of microcavity is λ and exciton is at different positions of microcavity, the peaks of luminous spectrum are all at the 520 nm of designed center wavelength, and the widths of half-peaks are all 12 nm. The peak intensity and integral intensity are smallest when exciton is in the central area of microcavity. After analyzing, The authors found that the light emitting characteristics is best when the exciton is at the maximum position of the electric field. This is because the electric field’s intensities in the microcavity with two kinds of lengths are distributed differently. It illustrates that one should distinguish different resonant cavity length and exciton at the maximum position of the electric field within microcavity if one wants to create an efficient MOLED..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 47 (2011)
Study on the Optical Properties of Semiconductor Nanocrystalline Powder Using Photoacoustic Technology
LIE Guang-hua, TANG Zhi-lie, YANG Ting, and TANG Xiu-wen
The optical properties of semiconductor nanocrystalline powder were studied by using photoacoustic spectroscopy technique. The band gap and the optical absorption coefficient of semiconductor nanocrystalline powder of TiO2, ZnO and Al-doped ZnO were measured by normalized photoacoustic spectroscopy technique. The resulThe optical properties of semiconductor nanocrystalline powder were studied by using photoacoustic spectroscopy technique. The band gap and the optical absorption coefficient of semiconductor nanocrystalline powder of TiO2, ZnO and Al-doped ZnO were measured by normalized photoacoustic spectroscopy technique. The results show that the optical properties of semiconductor nanocrystalline powder relate to particle size and particle shape. The band gap and the optical absorption coefficient of semiconductor nanocrystalline powder can be controlled by its fabricating techniques. By doping and changing the size and the shape of nanocrystals, changing the optical and electrical properties was achieved..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 51 (2011)
Research on Clouds Affecting the Spectra of Solar Ultraviolet Radiation
ZHAO Xiao-yan, YAN Hai-tao, ZHEN Zhi-qiang, TANG Zheng-xin, and WANG Hui
In the present paper, using UV CCD optical multi-channel analyzer, the solar ultraviolet radiation spectra under the conditions of cloud cover were measured, and the impact of clouds on the solar ultraviolet radiation spectra were studied mostly. The results of spectral analysis showed that the intensity of solar ultraIn the present paper, using UV CCD optical multi-channel analyzer, the solar ultraviolet radiation spectra under the conditions of cloud cover were measured, and the impact of clouds on the solar ultraviolet radiation spectra were studied mostly. The results of spectral analysis showed that the intensity of solar ultraviolet radiation spectra was weakened by the clouds. The solar ultraviolet radiation spectral intensity attenuation depended on the wavelength and decreased with decreasing wavelength. The greater the cloud cover, the stronger the attenuation, The solar ultraviolet radiation spectral intensity at wavelengths below 315 nm was affected relatively less by the cloud cover. These results have more important practical applications. When we use solar ultraviolet radiation spectrum to study the atmospheric composition, we should choose the spectral band that is less affected by the atmospheric environment..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 55 (2011)
Spectral Analysis of Oxygen Radical in a Synergistic System of Pulsed Discharge Plasma/TiO2
WANG Hui-juan, LI Jie, and CHU Jin-yu
Based on the synergistic effect of pulsed discharge plasma and titanium dioxide (TiO2) photocatalysis, a coupling system of pulsed discharge plasma/TiO2 was set up in the present paper, by using the ultraviolet radiation produced during the pulsed discharge process. TiO2 film immobilized on the glass beads was used as Based on the synergistic effect of pulsed discharge plasma and titanium dioxide (TiO2) photocatalysis, a coupling system of pulsed discharge plasma/TiO2 was set up in the present paper, by using the ultraviolet radiation produced during the pulsed discharge process. TiO2 film immobilized on the glass beads was used as the photocatalyst in the synergistic system. In the research, the synergistic mechanism of pulsed discharge plasma and TiO2 photocatalysis was reviewed by the spectral diagnosis of oxygen radical (·O radical) produced in different reaction systems. The obtained results showed that the characteristic emission spectrum of ·O radical could be observed at 777 nm and the corresponding transitions was 3p5P→3s5S. When air was used as bubbling gas, the relative emission intensity of ·O radical recorded in the synergistic system was stronger than that in the plasma alone system, and the same result was also obtained when oxygen (O2) was used as bubbling gas. This result revealed that the photocatalytic activity of the immobilized TiO2 in the synergistic system could be induced by the ultraviolet radiation formed during the pulsed discharge process. In the systems of pulsed discharge plasma alone and pulsed discharge plasma combined with TiO2 photocatalysis, the relative emission intensity of ·O radical in distilled water was stronger than that in phenol solutions. The results showed that ·O radical was one of responsible radicals for phenol degradation in the pulsed discharge plasma alone system as well as the synergistic system..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 58 (2011)
Research on Using Near Infrared Diffuse Reflectance Spectroscopy for Rapid Prediction of Compositions of Steamed-Flaking Corn
XUE Feng, WANG Li, MENG Qing-xiang, CUI Zhen-liang, and REN Li-ping
Near infrared diffuse reflectance spectroscopy (NIDRS) calibrations of chemical composition in 62 kinds of steamed-flaking corn were developed by partial least squares (PLS) regression. The calibration models were constructed by the mean centre+first deviation+multivariate scattering calibration in the square regions (Near infrared diffuse reflectance spectroscopy (NIDRS) calibrations of chemical composition in 62 kinds of steamed-flaking corn were developed by partial least squares (PLS) regression. The calibration models were constructed by the mean centre+first deviation+multivariate scattering calibration in the square regions (950～1 650 nm). Results showed that the R2VAL are 0.951 1, 0.903 2, 0.714 3 and 0.908 2 for CP, NDF, ADF and EE respectively. The SECV are 1.53, 1.89, 2.45 and 0.50 for CP, NDF, ADF and EE respectively. Therefore, the models could be used to predict the content of CP, NDF and EE in steamed-flaking corn and provide a fast and economical method for quality control of steamed-flaking corn..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 62 (2011)
Effects of Ultraviolet-B Radiation on Protein Structure in PSⅡ Using Fourier Transform Infrared Spectroscopy
LIU Xiao, TANG Weng-ting, LI Qian, and YUE Ming
The effects of ultraviolet-B (UV-B) radiation on protein structure in photosystem Ⅱ (PSⅡ) was studied using Fourier transform infrared spectroscopy. The results demonstrated that irradiation of the plant with enhanced UV-B caused the change in the structures of protein in PSII. The intensity of α-helix, β-sheet was incThe effects of ultraviolet-B (UV-B) radiation on protein structure in photosystem Ⅱ (PSⅡ) was studied using Fourier transform infrared spectroscopy. The results demonstrated that irradiation of the plant with enhanced UV-B caused the change in the structures of protein in PSII. The intensity of α-helix, β-sheet was increased, while the intensity of β-turn was decreased. The coupling of those structures with surrounding became weaker with UV-B radiation. Otherwise, the UV-B influenced the structure of tyrosine residue and made the polarity of tyrosine decrease. The changes caused by UV-B radiation could alter the combination between Mn cluster and pigments with protein inevitably. It would lead to a series of changes, such as the process of light transmission and conversion, electron transfer and oxygen evolution..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 65 (2011)
A Method for Quantitative Analysis System of Alkane Gaseous Mixture with Near Infrared Spectroscopy
ZHU Ling-jian, TANG Xiao-jun, QIU Zong-ming, LIU Jun-hua, ZHANG Zhong-hua, and ZHANG Yong
A method for online quantitative analysis system of alkane gaseous mixture with near infrared spectroscopy is described in the present paper. A single plane diffraction grating is used as the principal device in the monochromatic spectrum system. The key parameters of the monochromator were deduced and calculated in deA method for online quantitative analysis system of alkane gaseous mixture with near infrared spectroscopy is described in the present paper. A single plane diffraction grating is used as the principal device in the monochromatic spectrum system. The key parameters of the monochromator were deduced and calculated in detail. A quantitative analysis system was designed and constructed according to the parameters. The narrow-band beam testing experiments and spectral scanning experiments of seven kinds of single-component alkane gases were accomplished on the above hardware system platform. The narrow-beam experiments show that a 10 nm narrow-band beam spectra was successfully obtained by the monochromatic system when the entrance slit width is 2 mm. And a step-scanning resolution of the outgoing beam’s center wavelength with 0.1 nm can be realized within the spectra of 1.2～1.8 μm. The spectral scanning experiments indicate that there was some stronger characteristic absorption spectrum existing between the spectra of 1.6～1.8 μm, which is consistent with the HITRAN spectral database. And there is serious cross-aliasing phenomenon existing among the absorption spectra. These experiments demonstrate that this method has a successful application in mixed gas monitoring and on-line analysis with the characteristics of simple structure and low cost. And it also provides further technical reserves and opens a path way to spectral analysis in the follow-up studies..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 69 (2011)
Study on the Global and Local Calibration Methods of Tryptophan Content in Rice by Near Infrared Reflectance Spectroscopy
ZHANG Bin, ZHANG Da-peng, ZHANG Wen-bin, WANG Ke-min, LI Guan, YAO Ya-zhen, WU Jian-guo, and SHI Chun-hai
Tryptophan is one of the essential amino acids in human, and also considered as an important limiting amino acid in rice. Alkali hydrolysis method was used to determine the tryptophan content of 272 representative samples selected from the 1 256 samples in four years. Based on the milled rice flour spectroscopy, by comTryptophan is one of the essential amino acids in human, and also considered as an important limiting amino acid in rice. Alkali hydrolysis method was used to determine the tryptophan content of 272 representative samples selected from the 1 256 samples in four years. Based on the milled rice flour spectroscopy, by comparing the prediction abilities of the equations with global calibrations and local calibration, the global calibration method with MPLS and the local calibration method were better than others. Their calibration models could be introduced to application because of low standard errors of prediction for both methods (0.007%) and high coefficients of determination (87.1% and 87.4%, respectively). Furthermore, the prediction ability of the equation based on the brown rice spectroscopy could be still used for determination application though their effects were worse than that of the milled rice flour spectroscopy. It was concluded that the equation could be directly used to estimate the content of tryptophan in milled rice, and the technology of near infrared reflectance spectroscopy developed in this study could be applied in selecting breeding materials for higher tryptophan content and in quality control during rice processing..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 73 (2011)
Degradation Characteristics of Transgenic Cotton Residues in Soil by Fourier Transform Infrared Spectroscopy
CHEN Zhen-hua, ZHANG Yu-lan, JIA Yin-hua, CHEN Li-jun, LIU Xing-bin, and WU Zhi-jie
After transgenic cotton residues incubated in soil 430 d, the contents and structural characteristics of soil humus fractions, fulvic acid, humic acid and humin were measured by potassium dichromate titrimetric method and Fourier transform infrared spectroscopy. The results showed that all soil humus fractions increaseAfter transgenic cotton residues incubated in soil 430 d, the contents and structural characteristics of soil humus fractions, fulvic acid, humic acid and humin were measured by potassium dichromate titrimetric method and Fourier transform infrared spectroscopy. The results showed that all soil humus fractions increased after the degradation of cotton residues, and the most relative increase was with humin and the least was with fulvic acid. Compared to their near-isogenic non-transgenic cottons, soil humus content for transgenic Bt cotton residue decreased, and that forr transgenic Bt+CpTI cotton Z41 was approximate, but that for transgenic Bt+CpTI cotton SGK321 increased. Infrared spectroscopy of fulvic acid, humic acid and humin showed the addition of cotton residue decreased the content of oxygenous groups, and increased the alkyl and amide groups. There were differences in the speed to form soil humus among three transgenic cottons. Transgenic Bt cotton was slower than its counterpart, transgenic Bt+CpTI cotton Z41 was approximate to its counterpart, but transgenic Bt+CpTI cotton SGK321 was faster than its counterpart..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 77 (2011)
Concentration Inversion of High Temperature Air from FTIR Spectra and Analyzing Residual Error Structure
CHENG Si-yang, ZHANG Tian-shu, GAO Min-guang, LIU Zhi-ming, TONG Jing-jing, and JIN Ling
The spectral line widths of theory and experiment are analyzed with different temperatures; the line strengths under room temperature in HITRAN database are corrected to measured temperature, and then synthetic spectra are calculated. With the nonlinear least squares fit between measured spectra and calibration spectraThe spectral line widths of theory and experiment are analyzed with different temperatures; the line strengths under room temperature in HITRAN database are corrected to measured temperature, and then synthetic spectra are calculated. With the nonlinear least squares fit between measured spectra and calibration spectra, standard gas concentrations of CO at different temperatures are obtained. The inversion concentration error of this algorithm at room temperature is less than 5% with high precision. But with the temperature increasing, the concentration error will increase gradually. At the same time, there is the same apparent structure to component CO in the residual spectrum. Also, with higher temperature, the structure is more obvious and can not be removed by increasing the number of fitting. Comparing experimental results and theoretical analysis, the temperature correction methods of calibration spectra, which are not suitable for high temperature gas, are the main reason for inversion error at higher temperature. These results have important significance for further research on accurately correcting parameters and how to inverse the high temperature gas concentrations more accurately..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 82 (2011)
Homogeneous Immunoassay Technology Based on Near Infrared Upconversion Fluorescence Resonance Energy Transfer
SONG Kai, RAN Ying-ying, and KONG Xiang-gui
A FRET based assay utilizing NaYF4∶Yb3+, Tm3+ UCNPs as an energy donor, which can emit intense near infrared (NIR) upconversion emission around 800 nm ranges under illumination with a 980 nm laser, and GNPs as an energy acceptor, which has an surface plasmon absorption maximum at 784 nm, was demonstrated. Their opticalA FRET based assay utilizing NaYF4∶Yb3+, Tm3+ UCNPs as an energy donor, which can emit intense near infrared (NIR) upconversion emission around 800 nm ranges under illumination with a 980 nm laser, and GNPs as an energy acceptor, which has an surface plasmon absorption maximum at 784 nm, was demonstrated. Their optical properties satisfy the requirement of spectral overlap between donors and acceptors for FRET. A model assay for human IgG was then constructed, in which amino-functionalized NaYF4∶Yb3+, Tm3+ UCNPs and GNPs were first prepared and then conjugated with the antibody (goat antihuman IgG) and antigen (human IgG), respectively. The mutual affinity of the antigen and antibody brought the nanocrystals close enough together to allow the FRET to occur, resulting in a significant quenching of UCNPs upconversion emission at 800 nm. When free human IgG was added to the immunocomplex, it competitively binds to UCNPs-goat antihuman IgG, thereby replacing human IgG-GNPs from the immunocomplex and inhibits the FRET process. As a result, the gradually increasing the NIR emission was observed. The authors associate the fluorescence enhancement effect with the concentration of human IgG. Under our experimental conditions, the detection limit is 5 μg·mL-1. This approach is expected to be extended to the detection of other biological fields, enabling measurements without background fluorescence interference..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 86 (2011)
FTIR Analysis of Oil Shales from Huadian Jilin and Their Pyrolysates
XIE Fang-fang, WANG Ze, SONG Wen-li, and LIN Wei-gang
Thermochemical conversion is the key technology for the comprehensive utilization of Chinese oil shale resources. Oil shales from three mining areas of Huadian Jilin were pyrolyzed at 500 ℃ in a quartz tube reactor and their pyrolyzed cokes and shale oil were derived. One oil shale was also pyrolyzed at 600 ℃ and 700 ℃Thermochemical conversion is the key technology for the comprehensive utilization of Chinese oil shale resources. Oil shales from three mining areas of Huadian Jilin were pyrolyzed at 500 ℃ in a quartz tube reactor and their pyrolyzed cokes and shale oil were derived. One oil shale was also pyrolyzed at 600 ℃ and 700 ℃ to assess the influence of temperature on pyrolysates. FTIR analysis was carried out to study the raw shales and their products. The results showed that shale oil had similar functional groups as the organic matter of oil shale, mainly aliphatic hydrocarbon, and the shale oil contained more of it than the raw material. The shale with more aliphatic oil yielded more oil. That with less aliphatic and more aromatic one yields less oil, and its coke is rich in condensed aromatics. Pyrolysis was almost completed at 500 ℃. Oil yield did not increase further with temperature, but secondary pyrolysis strengthened. At 700 ℃ carbonates began to decompose..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 91 (2011)
Preparation and Spectroscopy Investigation of Vanadium Oxide Films Deposited by DC Magnetron Sputtering
LI Li-sha, CUI Hai-ning, and JIANG Zhen-yi
Vanadium oxide films were deposited at different substrate temperatures up to 400 ℃ by DC magnetron sputtering, and through the method of the X-ray diffraction, electron scanning microscopy, infrared and Raman spectra, the present paper studies the structure properties of those films, and through the method of spectrumVanadium oxide films were deposited at different substrate temperatures up to 400 ℃ by DC magnetron sputtering, and through the method of the X-ray diffraction, electron scanning microscopy, infrared and Raman spectra, the present paper studies the structure properties of those films, and through the method of spectrum measuring and fitting, this paper studies the optical properties of the films. At low temperature of preparation the optical films have high optical transmittance. The films prepared at low substrate temperature (lower than 200 ℃) have amorphous structure and some films prepared at high substrate temperatures (higher than 200 ℃) have polycrystalline structure. The films’ optical parameters were achieved by using classic model to fit the characteristic of transmittance..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 95 (2011)
Extraction of First Derivative Spectrum Features of Soil Organic Matter via Wavelet De-Noising
LIU Wei, CHANG Qing-rui, GUO Man, XING Dong-xing, and YUAN Yong-sheng
The hyperspectral reflectance of soil was measured by a ASD FieldSpec within 400~1 000 nm.Next, its first derivative of spectra were acquired and de-noised by the threshold de-noising method based on wavelet transform. From the de-noised derivative spectra, absorption areas used as indicatoresas for soil organic matterThe hyperspectral reflectance of soil was measured by a ASD FieldSpec within 400~1 000 nm.Next, its first derivative of spectra were acquired and de-noised by the threshold de-noising method based on wavelet transform. From the de-noised derivative spectra, absorption areas used as indicatoresas for soil organic matter content were acquired by numerical integration. Results show that: (1) Because of much noise, it is difficult to identify spectra contour and features in the first derivative of soil spectra resulting from different organic content levels. (2) When the scale of wavelet decomposition was 3, the threshold de-noising method based on wavelet transform can keep the balance between smoothing curve and holding spectra features. (3) Absorption area S(538, 586) is extracted from de-noised first derivative of soil spectra, and the coefficient of correlation between it and organic matter content is 0.896 3..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 100 (2011)
Rapid Determination of Chemical Components in Interstitial Water of Lake Sediments Using Near-Infrared Spectroscopy
HUO Shou-liang, ZAN Feng-yu, XI Bei-dou, ZHANG Jing-tian, LI Qing-qin, and HE Lian-sheng
The near infrared reflectance spectra (NIRS) of interstitial water samples of lake sediments in Chaohu lake were determined by near-infrared reflectance spectrometry. The respective near NIRS calibration models for predicting total nitrogen (TN), total organic carbon (TOC), phosphorus (PO3-3), ammonia nitrogen(NH3-N) aThe near infrared reflectance spectra (NIRS) of interstitial water samples of lake sediments in Chaohu lake were determined by near-infrared reflectance spectrometry. The respective near NIRS calibration models for predicting total nitrogen (TN), total organic carbon (TOC), phosphorus (PO3-3), ammonia nitrogen(NH3-N) and silicate(SiO-3) were built using partial least squares (PLS) algorithm with two spectral pretreatment tools including, wavelet compression combining orthogonal signal correction (OSC) and orthogonal signal correction (OSC) combining wavelet compression. The correlation coefficients between measured values and predicted values in calibration set for TN, NH3-N, PO3-3, TOC and SiO-3 were 0.975, 0.989, 0.937, 0.862 and 0.888, respectively. RMSEC(root mean square error of the calibration）for TN, NH3-N, PO3-3, TOC and SiO-3 were 0.353, 0.238, 0.031 3, 2.005 and 2.674 mg·L-1, respectively. The correlation coefficients between measured values and predicted values in validation set for TN, NH3-N, PO3-3, TOC and SiO-3 were 0.912, 0.918, 0.773, 0.337 and 0.856, respectively. RMSEP(root mean square error of the prediction）for TN, NH3-N, PO3-3, TOC and SiO-3 were 1.424, 0.945, 0.081, 7.866 and 4.273 mg·L-1, respectively..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 105 (2011)
SVM-Based Qualitative Analysis of Muscat Hamburg Wine Produced in Tianjin Region
ZHANG Jun, WANG Fang, WEI Ji-ping, LI Chang-wen, YANG Hua, SHAO Chun-fu, ZHANG Fu-qing, YIN Ji-tai, and XIAO Dong-guang
The purpose was to achieve the identification of Muscat Hamburg wines produced in Tianjin region through scanning and analyzing dry white wine samples of different grape varieties and regions by infrared spectroscopy technology. A support vector machine (SVM) based method was introduced to analyze infrared spectra of dThe purpose was to achieve the identification of Muscat Hamburg wines produced in Tianjin region through scanning and analyzing dry white wine samples of different grape varieties and regions by infrared spectroscopy technology. A support vector machine (SVM) based method was introduced to analyze infrared spectra of dry white wines. The pretreatment processes of the IR spectra were also elaborated, including baseline adjustment, noise Elimination, standard normalization and eliminating the main component of abnormal sample points. The authors selected great quantity of dry white wine samples of different grape regions including 511 Muscat Hamburg wine samples, 438 Italian Riesling wine samples, 307 Chardonnay wine samples, 29 Ugni Blanc wine samples, 44 Rkatsiteli wine samples, 31 longan wine samples and 79 ZeHong wine samples. According to different classification problems, 80% of IR spectra of the wine samples were used to establish discrimination models with SVM-based method, and the remaining 20% of IR spectra were used for the validation of the discrimination models. Experimental results showed that the proposed method is effective, since high classification accuracy, identification rate and rejecting rate were achieved: over 97% for the white wine samples of different grape varieties, meanwhile over 98% for the Muscat Hamburg wine samples produced in different regions. So the method developed in this paper played a good role in the qualitative classification and discrimination of Muscat Hamburg wines produced in Tianjin region. This novel method has a considerable potential and a rosy application future due to the expeditiousness, stability and easy-operation of FTIR method, as well as the veracity and credibility of SVM method..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 109 (2011)
Research on Diffuse Reflectance Infrared Fourier Transform Spectroscopy of Kinds of Kaolin in Various Areas
LI Xiao-hong, JIANG Xiang-ping, CHEN Chao, and TU Na
Respectively using pressed method and diffuse reflectance method, the infrared absorption spectrua of sorts of kaolin in various areas were obtained. The relationship between the structure characteristics of kaolin and its absorption peaks was analyzed. The results showed that compared with pressed method, the use of dRespectively using pressed method and diffuse reflectance method, the infrared absorption spectrua of sorts of kaolin in various areas were obtained. The relationship between the structure characteristics of kaolin and its absorption peaks was analyzed. The results showed that compared with pressed method, the use of diffuse reflectance Fourier transform infrared spectroscopy, combined with the K-M function, results in corrected infrared spectra with high sensitivity and is more accurate and easier to analyze. Furthermore, based on a high frequency wave of 3 700~3 600 cm-1 sections of kaolinite-OH characteristic absorption peaks, the crystallinity of all kinds of kaolnite can be known quickly. The result is consistent with the Hinckley index surveyed by X-ray diffraction technique..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 114 (2011)
DFT Feature Analysis of Corn Varieties Based on Near Infrared Spectra
LI Yang-peng, LI Wei-jun, and LAI Jiang-liang
The present paper develops a new approach to the analyse of corn based on discrete Fourier transform (DFT). The experiment data is of 37 varieties of corn seed with the Fourier transform near infrared spectrometer in the wave number range from 4 000 to 12 000 cm-1. Analyse of the origin data found that as the wave numbThe present paper develops a new approach to the analyse of corn based on discrete Fourier transform (DFT). The experiment data is of 37 varieties of corn seed with the Fourier transform near infrared spectrometer in the wave number range from 4 000 to 12 000 cm-1. Analyse of the origin data found that as the wave number increases, the data noise also increases. Firstly, the paper defines a calculation method of interspecific and intraspecific differences Qm to measure the effectiveness of feature selection. Secondly, Qm was used to analyse the original data and DFT-section data. Experimental results show that by choosing data of DFT with wave number range from 4 000 to 7 085 cm-1, the mean value and the peak value of the the Qm curve markedly improved relative to the full band original data. The mean value was enhanced from the original 4.804 9 to 8.513 8, and the max of the peak value was enhanced from the original 35.924 0 to 60.821 6, while the min of the peak value was enhanced from the original 2.891 8 to 3.741 5. Data feature points (Qm value of large point) are more concentrated than the original data after DFT. Such a result is most conducive to extracting the characteristics of corn seed..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 119 (2011)
Study of Raman and IR Spectra for Si—Al—Zr—O Amorphous Bulk In-Situ Crystallization
TAN Xiao-ping, LIANG Shu-quan, CHAI Li-yuan, ZHANG Guo-wei, and ZHANG Yong
The structural changes in the in-situ controlled crystallizing process of Si—Al—Zr—O(SAZ) amorphous bulk were investigated by laser Raman (LRa), infrared (IR) and X-ray diffraction (XRD) techniques. The structure of the amorphous network apparently reorganized at about 920 ℃, resulting in the formation of Si-rich and AThe structural changes in the in-situ controlled crystallizing process of Si—Al—Zr—O(SAZ) amorphous bulk were investigated by laser Raman (LRa), infrared (IR) and X-ray diffraction (XRD) techniques. The structure of the amorphous network apparently reorganized at about 920 ℃, resulting in the formation of Si-rich and Al, Zr-rich regions. The t-ZrO2 was crystallized from the Zr-rich region at 920~950 ℃ and poorly defined Al—Si spinel was formed from the Al-rich regions. With the increase in temperature, the peak of Al—Si spinel was enhanced and then disappeared in the XRD pattern, and the characteristic IR band groups of mullite centered in the 1 200~1 100, 1 000~700 and 650~400 cm-1 could be observed. At 1 100~1 150 ℃, the Raman bands at 179 and 193 cm-1 typical for the m-ZrO2 occurred and cristobalite was detected, and the main crystalline phases were identified as t-ZrO2 and mullite. These results indicated that mullite was formed by reaction between amorphous silica and the Al—Si spinel which was metastable phase. During the heating process, t-ZrO2 was crystallized firstly and a portion was transformed to m-ZrO2 at high temperature, and the left amorphous silica was transformed to cristobalite..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 123 (2011)
Raman Spectra of Aragonite at the Pressure of 0.1~2 GPa and Ambient Temperature
FU Pei-ge, and ZHENG Hai-fei
Raman spectra of aragonite were studied at ambient temperature and pressure of 0.1～2 GPa in a moissanite anvil cell using Raman spectrum technique. The relations between the Raman shifts of aragonite and the system pressure are given as follows: ν153(cm-1)=0.003 5p(MPa)+154.0, ν206=0.006 0p+206.3, ν704=0.002 1p+704.2, Raman spectra of aragonite were studied at ambient temperature and pressure of 0.1～2 GPa in a moissanite anvil cell using Raman spectrum technique. The relations between the Raman shifts of aragonite and the system pressure are given as follows: ν153(cm-1)=0.003 5p(MPa)+154.0, ν206=0.006 0p+206.3, ν704=0.002 1p+704.2, ν1 085=0.003 5p+1 085.3. No phase transition occurred in aragonite within the range of experimental pressure. Similar to other carbonate minerals (magnesite, dolomite), the measured relative pressure-shift of the Raman line of the symmetric stretching vibration of aragonite is greater at 0.1-2 GPa than at ultrahigh pressure, which indicates that the C—O bond compressibility of the CO3 groups is related to the pressure, and it is more compressible at 0.1～2 GPa than at higher pressure..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 127 (2011)
Rapid Determination of Melamine in Pet Food by Surface Enhanced Raman Spectroscopy in Combination with Ag Nanoparticles
CHENG Jie, and SU Xiao-ou
The rapid qualitative and quantitative analysis of melamine in pet food was realized by surface-enhanced Raman spectroscopy in combination with Ag nanoparticle. In the present study, the 709 and 1 542 cm-1 Raman shift was chosen as qualitative basis. The quantitative calculation of the concentration range between 1.0 aThe rapid qualitative and quantitative analysis of melamine in pet food was realized by surface-enhanced Raman spectroscopy in combination with Ag nanoparticle. In the present study, the 709 and 1 542 cm-1 Raman shift was chosen as qualitative basis. The quantitative calculation of the concentration range between 1.0 and 10.0 mg·kg-1 was achieved based on the intensity of 1 149 cm-1 Raman peak which was used as a normalization standard. The limit of detection was 0.5 mg·kg-1. The Ag nanoparticle had a strong Raman enhancement effect on melamine and the intensity was affected by the adding time of Ag nanoparticle and the vortex strength. At the same time, the intensity of SERS was affected by the extraction solvent type, and the manner of extracton. The analysis time of each sample was about 5 min. It was so quick that it was easy to realize the rapid detection of melamine in pet food compared with existing methods..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 131 (2011)
Fluorescence Characteristics of Different Chlorophyll a Concentration in Lake Taihu
LI Li, YIN Qiu, GONG Cai-lan, XU Hua, and CHEN Li-xiong
The spectral reflectance and water qualities of 27 stations were acquired in the lake Taihu during the months from May to August, 2008 when blue algal bloomed. Based on the fluorescence characteristics analysis of different chlorophyll a concentration, it was obvious that the position and height of fluorescence peak boThe spectral reflectance and water qualities of 27 stations were acquired in the lake Taihu during the months from May to August, 2008 when blue algal bloomed. Based on the fluorescence characteristics analysis of different chlorophyll a concentration, it was obvious that the position and height of fluorescence peak both have a positive correlation with chlorophyll a concentration, and the correlation coefficients between chlorophyll a concentration and position and half width of fluorescence peak are larger than those of the reference baseline and the normalized height of fluorescence. Estimating of chlorophyll a concentration in case 2 water using fluorescence characteristics is obviously better than the empirical algorithm based on blue to green ratio. Moreover, the common algorithm based on near infrared band to red band ratio is essentially consistent with the normalized height method..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 136 (2011)
Applications of Three-Dimensional Fluorescence Spectrum of Dissolved Organic Matter to Identification of Red Tide Algae
L Gui-cai, ZHAO Wei-hong, and WANG Jiang-tao
The identification techniques for 10 species of red tide algae often found in the coastal areas of China were developed by combining the three-dimensional fluorescence spectra of fluorescence dissolved organic matter (FDOM) from the cultured red tide algae with principal component analysis. Based on the results of prinThe identification techniques for 10 species of red tide algae often found in the coastal areas of China were developed by combining the three-dimensional fluorescence spectra of fluorescence dissolved organic matter (FDOM) from the cultured red tide algae with principal component analysis. Based on the results of principal component analysis, the first principal component loading spectrum of three-dimensional fluorescence spectrum was chosen as the identification characteristic spectrum for red tide algae, and the phytoplankton fluorescence characteristic spectrum band was established. Then the 10 algae species were tested using Bayesian discriminant analysis with a correct identification rate of more than 92% for Pyrrophyta on the level of species, and that of more than 75% for Bacillariophyta on the level of genus in which the correct identification rates were more than 90% for the phaeodactylum and chaetoceros. The results showed that the identification techniques for 10 species of red tide algae based on the three-dimensional fluorescence spectra of FDOM from the cultured red tide algae and principal component analysis could work well..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 141 (2011)
Synthesis and Fluorescence Properties of Europium Complexes with 4-(4-pyridyl formoyl) Benzoic Acid
ZHANG Yan-hui, HAO Yan-zhong, PEI Juan, LI Ying-pin, SUN Bao, and REN Ju-jie
Three new europium complexes, Eu(PFBA)3(H2O)4, Eu(PFBA)3Phen(H2O)3 and Eu(PFBA)3TPPO(H2O)3, were synthesized using 4-(4-pyridyl formoxyl) benzoic acid (HPFBA), 1,10-phenanthroline (phen) and triphenyl phosphine oxide(TPPO) as the ligands. In the complexes, two characteristic absorption bands of HPFBA due to νO—H (3 000Three new europium complexes, Eu(PFBA)3(H2O)4, Eu(PFBA)3Phen(H2O)3 and Eu(PFBA)3TPPO(H2O)3, were synthesized using 4-(4-pyridyl formoxyl) benzoic acid (HPFBA), 1,10-phenanthroline (phen) and triphenyl phosphine oxide(TPPO) as the ligands. In the complexes, two characteristic absorption bands of HPFBA due to νO—H (3 000-2 200 cm-1) and νCO (1 697 cm-1) disappear, the asymmetry stretching vibration νas(COO－) and symmetry stretching vibration νs(COO－) of carboxyl appear, and the Δν(νas(COO）)－νs(COO－)) values are all smaller than that of NaPFBA. The carboxyl group of the ligand HPFBA is dehydrogenated and coordinated to Eu3+ with a bidentate chelating mode. The fluorescence properties of the complexes were studied. Each complex shows five emission bands at about 583, 596, 618, 655 and 703 nm, which are assigned to the characteristic emission 5D0→7FJ(J=0, 1, 2, 3, 4) transitions of Eu3+, respectively. The fluorescence intensity becomes stronger after the addition of phen and TPPO, and TPPO is better, which is due to synergistic effect of the second ligands..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 145 (2011)
Studies on the Interaction of Gatifloxacin with Bovine Serum Albumin in the Presence of Carbon Nanotubes by Fluorescence Spectroscopy
ZHA Jun, HE Hua, LIU Tie-bing, LI Shan-shan, and JIAO Qing-cai
Fluorescence spectroscopy was used to investigate the influences of carbon nanotubes (CNTs) on the fluorescence of bovine serum albumin (BSA), the influences of CNTs on that of gatifloxacin (GFLX) , and the influences of GFLX on that of BSA with or without coexisting CNTs under imitated physiological condition. The expFluorescence spectroscopy was used to investigate the influences of carbon nanotubes (CNTs) on the fluorescence of bovine serum albumin (BSA), the influences of CNTs on that of gatifloxacin (GFLX) , and the influences of GFLX on that of BSA with or without coexisting CNTs under imitated physiological condition. The experimental results demonstrate that both gatifloxacin and carbon nanotubes could quench the intrinsic fluorescence of BSA, and the quenching mechanism is mainly static quenching. The fluorescence quenching action of GFLX on BSA was weakened in the presence of CNTs. The fluorescence quenching data were analyzed according to Stern-Volmer equation and double-reciprocal Lineweaver-Burk equation. It was shown that the quenching constant (KSV) and the binding constant (K) are decreased with the concentration of carbon nanotubes increasing. The effects of coexisting CNTs on GFLX-BSA interactions were discussed to offer a reference for the studies on the action mechanism of CNTs or GFLX with albumins in vivo..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 149 (2011)
Application of Synchronous Fluorescence in Identification of Spilled Oil at Sea
JIANG Feng-hua, ZHAO Mei-li, HAN Bin, ZHENG Li, WANG Xiao-ru, and Frank S C LEE
In order to screen and identify the source of spilled oils at sea, synchronous fluorescence scans combined with clustering analysis are proposed and applied to different crude oil and weathering crude oil. SFS data of Δl=25 nm were recorded and dealt with clustering analysis. The cluster results of SFS data in the rangIn order to screen and identify the source of spilled oils at sea, synchronous fluorescence scans combined with clustering analysis are proposed and applied to different crude oil and weathering crude oil. SFS data of Δl=25 nm were recorded and dealt with clustering analysis. The cluster results of SFS data in the range of 300～500 nm show that the crude oil and the weathering oil could separate completely. And the crude oils from different sea areas, also collected at different time, clustered into different groups, respectively. The results indicate that this method could preliminarily selected, and maybe serves as an assistant method in oil spill identification..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 154 (2011)
Synthesis and Fluorescence Properties of Complexes of Terbium with Red Fluorescence
DU Yan, ZHAO Yong-liang, FU Xiao-tao, SUN Hui-juan, and LI Xin
Two terbium complexes were synthesized, with dibenzoylmethane (HDBM) as the first ligand and 1,10-phenanthroline (phen), dipyrido［3,2-a:2′,3′-c］ quinoxaline as the second ligand. The studies of elemental analysis, rare earth complexometric titration, molar conduction, IR spectra, UV spectra, fluorescence excitation andTwo terbium complexes were synthesized, with dibenzoylmethane (HDBM) as the first ligand and 1,10-phenanthroline (phen), dipyrido［3,2-a:2′,3′-c］ quinoxaline as the second ligand. The studies of elemental analysis, rare earth complexometric titration, molar conduction, IR spectra, UV spectra, fluorescence excitation and emission spectra indicate that the complexes have the compositions of Tb (DBM)3phen and Tb (DBM)3dpq. The results show that the rare earth ion (Tb3+) was bonded with the carbonyl oxygen atom of DBM and nitrogen atoms of phen and dpq. For the terbium complexes prepared by precipitation, the peak positions of the transitions were similar with the ones of the common complexes. The peaks at 490, 545, 586 and 621 nm were assigned to the 5D4→7F6, 5D4→7F6, 5D4→7F6, 5D4→7F6 transitions. For the fluorescence intensities of their 5D4→7F6, 5D4→7F5 and 5D4→7F4 transitions were lower than that of the 5D4→7F3 transition, the terbium complexes did not exhibite the characteristic fluorescence (green), but strong red fluorescence. The reason why terbium complexes exhibit the red fluorescence was investigated in the paper by studying the triplet state of ligands, the energy level transitions of complexes and the aggregation state of particles..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 158 (2011)
Light Absorption by Suspended Particulate Matter in Chagan Lake, Jilin
WANG Yuan-dong, LIU Dian-wei, SONG Kai-shan, ZHANG Bai, WANG Zong-ming, JIANG Guang-jia, TANG Xu-guang, LEI Xiao-chun, and WU Yan-qing
Spectral characteristics and the magnitudes of light absorption by suspended particulate matter were determined by spectrophotometry in this optically complex Lake Chagan waters for the purpose of surveying the natural variability of the absorption coefficients to parameterize the bio-optical models for converting sateSpectral characteristics and the magnitudes of light absorption by suspended particulate matter were determined by spectrophotometry in this optically complex Lake Chagan waters for the purpose of surveying the natural variability of the absorption coefficients to parameterize the bio-optical models for converting satellite or in-situ water reflectance signatures into water quality information. Experiments were carried out on seasonal frozen Lake Chagan, one representative inland case-2 water body in Northeast of China. Particulate absorption properties analyzed using the field data on July 15th and October 12th 2009 were measured using the quantitative filter technique to produce absorption spectra containing several fractions that could be attributed to two main optical active constituents (OACs) phytoplankton pigments and non-algal particulates (mineral sediments, and organic detritus). Results suggested that the suspended particulate matter (SPM) concentration was higher while phytoplankton biomass (chlorophyll-a concentration) was lower in July and that in October. The spectral shape of total suspended particulate matter resembled that of non-algal particulates which contributed greater than phytoplankton in total particulate absorption during both periods. An obvious absorption peak occurring at around 440 nm exhibited an increase in phytoplankton contribution in October. Non-algal particulate absorption at 440 nm (aNAP(440)) had better correlation with total suspended particulate matter concentration than that with chlorophyll-a over the two periods.Light absorption by phytoplankton pigments in the Chagan lake region was generally lower than that of non-algal components. Chl.a dominating phytoplankton pigment composition functioned exponentially with its absorption coefficients at 440 and 675 nm specifically, the average values of which in July were 0.146 8 m2·mg-1 and 0.050 3 respectively while in October they were 0.153 3 and 0.013 2 m2·mg-1 varying regionally and seasonally due to the changes in specific composition, light and nutrient conditions..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 162 (2011)
Composition Analyses of Urinary Microcrystalline in Urine of Magnesium Ammonium Phosphate Stones Formers and Its Relationship with the Stones Formation
YANG Jin, HUANG Zhi-jie, HOU Shan-hua, and OUYANG Jian-ming
By means of X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), nano-particle size analyzer, scanning electron microscopy (SEM) and transmission electron microscopy (TEM), the composition, morphology, particle size and zeta potential of urinary microcrystalline in urine of magnesium ammonium phosphBy means of X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), nano-particle size analyzer, scanning electron microscopy (SEM) and transmission electron microscopy (TEM), the composition, morphology, particle size and zeta potential of urinary microcrystalline in urine of magnesium ammonium phosphate stone formers were investigated. The components of stones were also analyzed. The results showed that there was a close relationship among stone components, urinary microcrystalline composition and urine pH. A high pH value of 6.5 or more usually appeared in the urine of magnesium ammonium phosphate stone formers. The main component of urine microcrystalline was magnesium ammonium phosphate crystals with different crystal water such as monohydrate or hexahydrate. Magnesium ammonium phosphate crystals are mainly petal-shaped, crosswise shape. These microcrystalline have an uneven particle size distribution, a wider distribution range, and apparent aggregation. There is no significant difference in the zeta potential between the magnesium ammonium phosphate stone formers (mean (-9.83±0.66) mV) and healthy control subjects (mean (-10.74±0.25) mV). This study can help predict the occurrence of urolithiasis, and provide inspiration to the prediction of the type of urinary stones..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 168 (2011)
Prediction of As in Soil with Reflectance Spectroscopy
ZHENG Guang-hui, ZHOU Sheng-lu, and WU Shao-hua
In the present study, visible-near infrared reflectance spectroscopy (VNIR) measured in laboratory was evaluated for prediction of the content of As in soils. Calibrations between As and reflectance were developed using cross-validation under partial least squares regression (PLSR). Prediction accuracy was tested via sIn the present study, visible-near infrared reflectance spectroscopy (VNIR) measured in laboratory was evaluated for prediction of the content of As in soils. Calibrations between As and reflectance were developed using cross-validation under partial least squares regression (PLSR). Prediction accuracy was tested via separate validation samples. The reflectance was pre-processed by several techniques like smoothing, multiplicative scatter correction (MSC), Log(1/R), first/second derivative (F/SD) and continuum removal (CR). The accuracy of prediction was evaluated with three statistics: coefficients of determination (R2), ratio of performance to deviation (RPD), and root mean square error of prediction (RMSEP). The results of calibration, cross-validation and prediction of different pre-processing techniques, spectral resolution and OM content were compared. MSC provided better prediction(Prediction R2=0.711, RPD=1.827, RMSEP=1.613) than other methods because it removed the effects of light scattering and sample thickness. All the results of different resolution are acceptable (Prediction 0.678＜R2＜0.711, 1.750＜RPD＜1.827, 1.613＜RMSEP＜1.685). The prediction accuracy of subsets with lower OM content(Prediction R2=0.694, RPD=1.697, RMSEP=1.644) was better than that with higher content. The study indicates that it is feasible to predict As element in soils using reflectance spectroscopy and the prediction accuracy can be improved by pre-processing. Thus this new rapid and cost-effective technique can be used in the monitoring of soil contamination..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 173 (2011)
Fast Segmentation Algorithm of High Resolution Remote Sensing Image Based on Multiscale Mean Shift
WANG Lei-guang, ZHENG Chen, LIN Li-yu, CHEN Rong-yuan, and MEI Tian-can
Mean Shift algorithm is a robust approach toward feature space analysis and it has been used wildly for natural scene image and medical image segmentation. However, high computational complexity of the algorithm has constrained its application in remote sensing images with massive information. A fast image segmentationMean Shift algorithm is a robust approach toward feature space analysis and it has been used wildly for natural scene image and medical image segmentation. However, high computational complexity of the algorithm has constrained its application in remote sensing images with massive information. A fast image segmentation algorithm is presented by extending traditional mean shift method to wavelet domain. In order to evaluate the effectiveness of the proposed algorithm, multispectral remote sensing image and synthetic image are utilized. The results show that the proposed algorithm can improve the speed 5-7 times compared to the traditional MS method in the premise of segmentation quality assurance..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 177 (2011)
Monitoring the Flux of Carbon Dioxide Gas with Tunable Diode Laser Absorption Spectroscopy
SONG Xue-mei, LIU Jian-guo, ZHANG Yu-jun, ZENG Zong-yong, HE Ying, CUI Yi-ben, CHEN Yin, TIAN Yong-zhi, and ZHANG Liang
The greenhouse effect exacerbated by the increase of Carbon-containing gases is the more important causes of the climate change, It is very meaningful to the large-scale flux of carbon dioxide detection for the estimate the contributions of the main greenhouse gases in the atmosphere of various errestrial eco-systems. The greenhouse effect exacerbated by the increase of Carbon-containing gases is the more important causes of the climate change, It is very meaningful to the large-scale flux of carbon dioxide detection for the estimate the contributions of the main greenhouse gases in the atmosphere of various errestrial eco-systems. Tunable diode laser absorption spectroscopy (TDLAS) is a highly sensitive, highly selective and fast time response trace gas detection technique. In the present paper, the authors used a DFB laser was used as the light source, and by employing wavelength modulation method, and measuring the second harmonic signal of one absorption line near 1.573 μm of carbon dioxide molecule, the authors built a system for online monitoring of carbon dioxide concentration within the optical path of more than 700 meters at different heights. Combined with Alonzo Mourning -Obukhov length and characteristic velocity detected by large aperture scintillometer, the flux of carbon dioxide gas within one day calculated by the formula is within -1.5～2.5, breakking through the phenomenon of only providing the flux of trace gases near the ground at present, makking the measurement of trace gas fluxes within a large area possible..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 184 (2011)
Study on Relationship between New Characteristic Parameters of Spectral Curve and Chlorophyll Content for Rice
XU Xin-gang, ZHAO Chun-jiang, WANG Ji-hua, HUANG Wen-jiang, LI Cun-jun, and LIU Huan-jun
It is of significance to monitor chlorophyll content with hyperspectral data for crop growth diagnosis in field. In the study, with the point of view that spectral curve shapes display “tall, low, fat and thin” morphological changes, we proposed some new characteristic parameters from spectral curve such as the ascensiIt is of significance to monitor chlorophyll content with hyperspectral data for crop growth diagnosis in field. In the study, with the point of view that spectral curve shapes display “tall, low, fat and thin” morphological changes, we proposed some new characteristic parameters from spectral curve such as the ascensive or degressive velocities of segments composing peak or valley shapes in spectral curve, and angles formed by the lines fitting the segments of two sides of peak or valley curves, and used the normalized spectra to analyze correlation between these parameters and rice chlorophyll content. The result shows that (1) there is a good negative correlation between rice chlorophyll content and normalized reflectance spectra from 520-740 nm ; (2) characteristic parameters from green peak region of spectral curve display better correlation with rice chlorophyll content, which makes it possible to utilize the parameters to monitor crop chlorophyll content, and will provide new ideas and methods for carrying out crop growth diagnosis with hyperspectral data..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 188 (2011)
Analysis and Modeling of Hyperspectral Singularity in Rice under Cd Pollution
XIU Li-na, LIU Xiang-nan, and LIU Mei-ling
In order to detect the Cd stress levels of rice growing in natural environment fast and accurately, based on wavelet transform technology in the visible light and near-infrared region (NIR), a method of identifying stress levels of rice under Cd pollution was explored. The hyperspectral data, biochemical parameters andIn order to detect the Cd stress levels of rice growing in natural environment fast and accurately, based on wavelet transform technology in the visible light and near-infrared region (NIR), a method of identifying stress levels of rice under Cd pollution was explored. The hyperspectral data, biochemical parameters and heavy metals concentration in folium were collected for the rice growing in natural farmlands. Wavelet transform of hyperspectral reflectance (350～1 300 nm) was performed by using Daubechies 5 mother function and wavelet energy coefficients of spectral reflectance were extracted. In addition, the model between wavelet energy coefficient and Cd content was established. The result showed that the wavelet coefficients of the fifth decomposition level (d5) proved successful for detecting Cd pollution of rice; the singularity range of rice located in the region around 550~810 nm of spectral signal under Cd pollution; and the singularity amplitude was 0.04; The centre of modulus maxima located at 700 nm. Regression model based on third level wavelet energy coefficient can estimate the Cd content of rice accurately with the coefficient of determination (R2) of 0.958, and root mean square error (RMSE) of 0.122. It can be concluded that the singularity analysis technology applying wavelet transform to reflectance has been shown to be very promising in detecting rice under Cd pollution effectively, and wavelet energy coefficients can estimate Cd content of rice, and provide important reference for detecting other metal-induced stress on crop..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 192 (2011)
Concentration Retrieving Method of SO2 Using Differential Optical Absorption Spectroscopy Based on Statistics
LIU Bin, SUN Chang-ku, ZHANG Chi, ZHAO Yu-mei, and LIU Jun-ping
A concentration retrieving method using statistics is presented, which is applied in differential optical absorption spectroscopy (DOAS) for measuring the concentration of SO2. The method uses the standard deviation of the differential absorption to represents the gas concentration. Principle component analysis (PCA) mA concentration retrieving method using statistics is presented, which is applied in differential optical absorption spectroscopy (DOAS) for measuring the concentration of SO2. The method uses the standard deviation of the differential absorption to represents the gas concentration. Principle component analysis (PCA) method is used to process the differential absorption spectrum. In the method, the basis data for the concentration retrieval of SO2 is the combination of the PCA processing result, the correlation coefficient, and the standard deviation of the differential absorption. The method is applied to a continuous emission monitoring system (CEMS) with optical path length of 0.3 m. Its measuring range for SO2 concentration is 0～5 800 mg·m-3. The nonlinear calibration and the temperature compensation for the system were executed. The full scale error of the retrieving concentration is less than 0.7%FS. And the measuring result is -4.54 mg·m-3 when the concentration of SO2 is zero..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 197 (2011)
Hyperspectral of the Body Surface Tissues: a New Synchronous Detection Technology of the Compositional Information and Structural Information
LIN Ling, WU Hong-jie, WU Xiao-shuang, and LI Gang
The present paper innovatively proposed the technology using hyperspectral to detect the body surface tissues that can achieve the systemic analysis of composition and structure by obtaining the multiple spectrum and image information simultaneously. Besides, by the method of data mining, the relationships between diseThe present paper innovatively proposed the technology using hyperspectral to detect the body surface tissues that can achieve the systemic analysis of composition and structure by obtaining the multiple spectrum and image information simultaneously. Besides, by the method of data mining, the relationships between diseases and the data including the spectrum, image or synentropy were established. This technology provided more information for the disease detection clinically which can reflect accurately the physiological, biochemical and pathological status and the variation of the body surface tissues, by which both the cost of the equipment and the operation steps can be reduced..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 201 (2011)
Removal of Methyl Orange from Aqueous Solution by Magnetic Carbon Nanotubes
HU Shu-wan, LI Wen-jun, CHANG Zhi-dong, WANG Huan-ying, GUO Hui-chao, ZHANG Jing-hua, and LIU Yang
Ferrocene was used as a catalyst, and xylene as carbon source. Chemical vapor deposition method was used to synthesize carbon nanotubes (CNTs). The CNTs were treated by oxidation method with concentrated nitric acid. Magnetic carbon nanotubes were prepared by using chemical co-precipitation. The products were characterFerrocene was used as a catalyst, and xylene as carbon source. Chemical vapor deposition method was used to synthesize carbon nanotubes (CNTs). The CNTs were treated by oxidation method with concentrated nitric acid. Magnetic carbon nanotubes were prepared by using chemical co-precipitation. The products were characterized by field emission scanning electron microscope. This paper is concerned with the adsorption of methyl orange by magnetic carbon nanotubes. The best experimental conditions were found. Adsorbent solution was analyzed by UV-Vis adsorption spectra. At the same time, desorption and re-adsorption of methyl orange from magnetic CNTs were studied..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 205 (2011)
In Vivo Identification of Radix Panacis Quinquefolii by Spectral Imaging Technology
ZHAO Jing, PANG Qi-chang, MA Ji, LIU Chuan-ming, WANG Lin, and CUI Dai-jun
Radix Panacis quinquefolii pieces coming from different drug stores were tested by crystal liquid spectral imaging instrument, and a new method for quality control was presented. The spectral resolution is 5 nm, the spectral range is from 405 to 680 nm, and the spatial resolution is 50 lp·mm-1.The characteristic sRadix Panacis quinquefolii pieces coming from different drug stores were tested by crystal liquid spectral imaging instrument, and a new method for quality control was presented. The spectral resolution is 5 nm, the spectral range is from 405 to 680 nm, and the spatial resolution is 50 lp·mm-1.The characteristic spectrum from spectral cube was used to construct the fingerprint of Radix Panacis quinquefolii, and the fingerprint was analyzed by principal method to identify the counterfeit and to evaluate the quality. The result is fully consistent with biological character and chemical analysis result. So the technology is suitable for fingerprint construction and quality evaluation of traditional Chinese medicine. The whole testing process is noninvasive, fast and convenient..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 210 (2011)
Study on Discrimination of Varieties of Milk Based on FISS Imaging Spectral Data
HUANG Chang-ping, ZHANG Li-fu, ZHANG Xiao-hong, ZHENG Lan-fen, and TONG Qing-xi
Using a self-developed field imaging spectrometer system (FISS), hyperspectral images of 14 typical kinds of milk were acquired, based on which the discrimination of varieties of milk was studied. Firstly, removing 2 abnormal samples, the remaining 12 kinds of milk were randomly sampled, a total of 1 200 pixel samples.Using a self-developed field imaging spectrometer system (FISS), hyperspectral images of 14 typical kinds of milk were acquired, based on which the discrimination of varieties of milk was studied. Firstly, removing 2 abnormal samples, the remaining 12 kinds of milk were randomly sampled, a total of 1 200 pixel samples. To eliminating high-frequency random noises and baseline offset and decrease the multi-collinearity, all samples were preprocessed by smooth-moving average and first derivative. Secondly, multiple discriminant analysis models for milk were built using characteristic wavelengths selected by the stepwise method. Results demonstrated that the overall identification accuracy for 1 200 spectral samples put together reached 95.5%, of which the overall distinguishing rate of Mengniu, Yili and Guangming acidophilous milk was 88.3%. The discriminant models for the three kinds of acidophilous milk subset, 300 spectral samples in all, were built, with the overall distinguishing rate of 88.7%. This explicated that FISS would be useful for discriminating milk varieties, and to accomplish specific discrimination of milk varieties, it would be best for milk of the same type from different manufacturers to form a subset, which may not only reduce the model variables, improving operational efficiency and the stability of the model, but improve their overall discriminant accuracy..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 214 (2011)
Application of Spectral Imaging Analysis in the Sibship Discussion of Folium Uncariae
MENG Qing-xia, PANG Qi-chang, MA Ji, ZHANG Hong-wei, and ZHAO Jing
In the present paper, using designed liquid crystal spectral imaging device, the transmission spectra of leaves of uncaria were detected and analysed under different environmental situations. The characteristic curve was drawn and the imaging characteristic spectrum was constructed and cluster analysis was performed. TIn the present paper, using designed liquid crystal spectral imaging device, the transmission spectra of leaves of uncaria were detected and analysed under different environmental situations. The characteristic curve was drawn and the imaging characteristic spectrum was constructed and cluster analysis was performed. The results showed the similarity of imaging characteristic spectrum of uncaria leaves and the results of determining genetic relationship in cluster analysis were consistent with the results of the identification of plant taxonomy. Spectral imaging analysis techniques can be applied to discuss the genetic relationship of uncaria. The liquid crystal spectral imaging system can detect traditional Chinese medicine rapidly and nondestructively. The same sample can be used to repeat several experiments. Experimental operation is simple and quick. It can provide a new detection method for Chinese medicine..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 219 (2011)
Spectroscopic Analysis Studies of Organo-Attapulgite/Nylon 6 Composites
SHI Jian-she, ZHANG Chun-xiang, YANG Xu-jie*, LU Lu-de, and WANG Xin
The surface organic modification of attapulgite with silane coupling reagent was studied by Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). Qrgano-attapulgite/nylon 6 composites with different content of attapulgite were prepared by means of melt blending, and the crystal struThe surface organic modification of attapulgite with silane coupling reagent was studied by Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). Qrgano-attapulgite/nylon 6 composites with different content of attapulgite were prepared by means of melt blending, and the crystal structure and morphology were investigated. The results show that the surface content of Si, N and C of the modified attapulgite increased. Combined with the FTIR results, it was confirmed that an organic coating layer was formed on the surface of attapulgite. The adding of attapulgite does not change the crystal structure of nylon 6, but changes the crystallite size of nylon 6. The modified attapulgite was well dispersed in nylon 6 and the silane coupling coating on the attapilgite enhanced the interfacial adhesion..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 223 (2011)
Contrastive Analysis on Soil Alkalinization Predicting Models Based on Measured Reflectance and TM Image Reflectance
ZHANG Fang, XIONG Hei-gang, LONG Tao, and LU Wen-juan
Based on the monitored data of soil pH and measured Vis-NIR reflectance on spot in Qitai oasis alkalinized area in Xinjiang, as well as comparison of the relationship between measured reflectance and soil pH and the relationship between TM reflectance and soil pH, both of the reflectance multivariate linear regression Based on the monitored data of soil pH and measured Vis-NIR reflectance on spot in Qitai oasis alkalinized area in Xinjiang, as well as comparison of the relationship between measured reflectance and soil pH and the relationship between TM reflectance and soil pH, both of the reflectance multivariate linear regression models were built to evaluate soil alkalinization level, and the model accuracy of pH fitting was discussed with error inspection of post-sample. The results showed that there is a significant positive correlation between soil pH and reflectance. With pH rising the reflectance increased concurrently. So the alkalinization soil characterized by hardening had good spectral response characteristics. Both measured reflectance and TM image reflectance had good potential ability for change detection of the alkalinization soil. The pH predicting model of measured reflectance had higher accuracy and the major error was from different hardening state. If building model by TM reflectance directly, the accuracy of fitting was lower because of the vegetation information in image spectrum. With the vegetation factor removed with NDVI, the accuracy of TM predicting model was near the accuracy of measured reflectance predicting model, and both of the model levels were good..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 227 (2011)
Ultraviolet Spectrum Analysis Methods for Detecting the Concentration of Organic Pollutants in Water
WU Yuan-qing, DU Shu-xin, and YAN Yun
The absorption rate of ultraviolet could be used to measure the concentration of organic pollutant, as most of the organic pollutant has stronger absorption rate in ultraviolet region in water. In the present paper, principal component regression (PCR), partial least squares (PLS), and support vector machine (SVM) wereThe absorption rate of ultraviolet could be used to measure the concentration of organic pollutant, as most of the organic pollutant has stronger absorption rate in ultraviolet region in water. In the present paper, principal component regression (PCR), partial least squares (PLS), and support vector machine (SVM) were respectively used to model a regression model after the spectrum preprocessing, such as smoothing, derivation, standard normal variate transformation (SNV), etc. Then, the concentration of organic pollutant could be measured via the ultraviolet spectrum and the regression model. In the experiments, a group of water samples from the wastewater treatment process were used to verify the effects of the various preprocessing and modeling approaches. The results showed that for the good spectrum data, direct modeling without the spectrum pretreatment could be used since the pretreatment would worsen the results. LSSVM approach is more applicable in the case of small-size samples..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 233 (2011)
Bamboo Carbon as Sorbent for the Separation and Preconcentration of Bismuth with Detection by HG-AFS and ICP-MS
CHEN Ming-li, SHEN Li-ming, and WANG Jian-hua
A procedure for the separation and preconcentration of bismuth was developed in a sequential injection system by employing bamboo carbon as sorbent. The detection was facilitated by both hydride generation atomic fluorescence spectrometry and inductively coupled plasma mass spectrometry. With a sample volume of 1 mL, aA procedure for the separation and preconcentration of bismuth was developed in a sequential injection system by employing bamboo carbon as sorbent. The detection was facilitated by both hydride generation atomic fluorescence spectrometry and inductively coupled plasma mass spectrometry. With a sample volume of 1 mL, a detection limit of 13 ng·L-1 was obtained, along with a precision of 0.9%(0.3 μg·L-1, n=9) with detection by HG-AFS, and a detection limit of 10 ng·L-1 along with a precision of 2.8% (0.3 μg·L-1, n=5) was achieved with detection by ICP-MS. The present system was validated by analyzing a certified reference material of river sediment (CRM 320), and spiking recovery of bismuth in human whole blood was performed with hydride generation atomic fluorescence spectrometry. No significant difference was identified in the results of bismuth detection in blood samples by hyphenating the present solid phase extraction system with detection by hydride generation atomic fluorescence spectrometry and inductively coupled plasma mass spectrometry..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 238 (2011)
Direct Determination of Copper, Iron and Sodium in High-Purity Alumina by Slurry Introduction Furnace Atomic Absorption Spectrometry with Smith-Hieftje Background Correction
LU Gui-ping, WANG Zheng, QIU De-ren, ZOU Hui-jun, and HE Yan-feng
Direct determination of copper, iron and sodium in high-purity alumina was performed by slurry-furnace atomic absorption spectrometry with Smith-Hieftje background correction (S-H-GFAAS). Instrument conditions of GFAAS such as pyrolysis, atomization and hollow cathode lamp current by S-H background correction were optiDirect determination of copper, iron and sodium in high-purity alumina was performed by slurry-furnace atomic absorption spectrometry with Smith-Hieftje background correction (S-H-GFAAS). Instrument conditions of GFAAS such as pyrolysis, atomization and hollow cathode lamp current by S-H background correction were optimized, and the optimal experimental conditions were selected. Calibration was performed using aqueous standards method for sample analysis. The accuracy of the proposed method was shown for the case of Al2O3 (AKP-30), and compared with those obtained by furnace atomic absorption spectrometry subsequent to decomposition by sulfuric acid in PTFE pressure vessels. The results were in agreement well with values found in the literature by different methods. It is a simple, convenient and accurate method and it is suitable for the rapid analysis of trace element in alumina. The linear regression coefficients of the calibration curves were better than 0.999 0. The detection limits were 0.66, 2.5 and 0.13 ng·g-1, respectively, with a relative standard deviation being not more than 5.2%..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 244 (2011)
Analysis of Methylmercury in Biological Guano by the Optimized Atomic Fluorescence Spectrometry Coupled with Microwave Assisted Extraction
CHEN Qian-qian, LIU Xiao-dong, SUN Li-guang, JIANG Shan, YAN Hong, LIU Yi, LUO Yu-han, and HUANG Jing
The analytical method for the determination of methylmercury in seabird excrements was established using atomic fluorescence spectrometry coupled with microwave-assisted extraction. In general, temperature and hydrochloric amount are the most important influencing factors on the extraction of MeHg in the samples, and tThe analytical method for the determination of methylmercury in seabird excrements was established using atomic fluorescence spectrometry coupled with microwave-assisted extraction. In general, temperature and hydrochloric amount are the most important influencing factors on the extraction of MeHg in the samples, and the present paper optimized these two parameters. The result showed that 120 ℃ and 200 μL 6 mol·L-1 hydrochloric acid are the best extraction conditions. Under these experimental conditions, the relative standard deviation (RSD) values of reduplicative analyses on standard reference material (human hair powder) and the same seabird excrement sample were 0.74% and 6.61% respectively, and their percent recoveries were over 90%. The combination of microwave-assisted extraction and atomic fluorescence spectrometry has many advantages such as simple operation, high sensitivity, low detection limit and low cost, therefore, it is suitable for rapid separation and analysis of trace methylmercury composition in the biological guanos. Using this method, we analyzed the methylmercury contents in the ancient and fresh seabird droppings taken from Xisha Islands of South China Sea, and the result showed that the Xisha guanos were rich in methylmercury and the large input of seabird guanos will cause serious environmental contamination in the remote island ecosystem of Xisha Islands..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 249 (2011)
Spectrometric Determination of Trace Elements in Anticancer New Medicine Fagopyrum Dibotrys
WANG Ji-yong, WANG Yuan-zhong, ZENG Yan, and LI Jin-tong
The golden buckwheat Fagopyrum dibotrys produced in Yunnan has a unique anti-cancer effects.It is a main raw material of “Wei Mai ning” capsules which is the national second-class anti-cancer drug. The present paper used(5∶1) mixed acid as digestive juice to process the sample, and determine the twelve elements includiThe golden buckwheat Fagopyrum dibotrys produced in Yunnan has a unique anti-cancer effects.It is a main raw material of “Wei Mai ning” capsules which is the national second-class anti-cancer drug. The present paper used(5∶1) mixed acid as digestive juice to process the sample, and determine the twelve elements including K, Ca, Cu, Na, Mg, Mn, Fe, Zn, Pb, Cr, Cd and Co in the Fagopyrum dibotrys by inductively coupled plasma atomic emission spectrometry(ICP-AES). The detection limits of this method were 0.017～0.084 μg·mL-1, the RSDs (n=8) were all 0.09%～1.87%, and the addition standard recoveries(ASR)(n=8) were 98.2%～107.4% for all elements. The research results showed that there is rich K(1 477.3 μg·g-1） in the Fagopyrum dibotrys, there are not harmful elements Cd and Pb, and this result is mainly related to the geochemistry background where the sample lived. The contents of seven remaining kinds of elements ranked as Na(826.1）>Ca(765.2>Mg(493.4）>Zn(112.7）>Fe(56.5）>Cu(11.4）>Mn(4.49 μg·g-1）. This result provides some theoretical basis for the study of internal relations between trace elements in Fagopyrum dibotrys and efficacy. It’ s also useful for better development and utilization of the resource..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 253 (2011)
Determination of 5 Heavy Metals in Chinese Traditional Medicines and Extraction Liquid Containing Mineral Materials
BAI Guo-yin, WEI Chao, OUYANG Li, XIE Qing, LIU Ya-qiong, WANG Jun, and WANG Jing-yu
Chinese traditional medicine (CTM) containing realgar may contain high levels of toxic metals, such as arsenic, etc. The monitoring of trace elements, especially the harmful elements, is closely related to the quality control of the CTM. Three kinds of CTM containing realgar were digested by microwave method and electrChinese traditional medicine (CTM) containing realgar may contain high levels of toxic metals, such as arsenic, etc. The monitoring of trace elements, especially the harmful elements, is closely related to the quality control of the CTM. Three kinds of CTM containing realgar were digested by microwave method and electric heating plate method, and As, Hg, Cu, Cd and Pb were determined using ICP-MS and ICP-AES. In addition, this research determined the content of soluble heavy metals in the human gastrointestinal solution. The results showed that three kinds of CTM contained As of 24 350～68 627 mg·kg-1; Hg of 0.26～122 313.6 mg·kg-1; Cu of 2.04～6.95 mg·kg-1; Cd of 0.02～1.46 mg·kg-1; Pb of 0.42～40.60 mg·kg-1. In comparison, the contents of soluble heavy metals in the human gastrointestinal solution are: As of 81～618 mg·L-1; Hg of 0.34～216 mg·L-1; Cu of 1.08～215 mg·L-1, and Pb, Cd were not detected..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 256 (2011)
Hydrophobic Ionic Liquid Extraction-Flame Atomic Absorption Spectrophotometry for Separation/Analysis Trace Gold
WU Jun, FU Hao, LI Bin-jian, and ZHU Xia-shi
In the present paper, the hydrophobicity ionic liquid 1-butyl-3- methylimidazolium hexafluorophosphate (［C4mim］［PF6］) was synthesized with 1-methylimidazole and butylbromide and equimolar ammonium hexafluorophosphate, which was applied to preconcentration for trace gold. The factors which may affect preconcentration ofIn the present paper, the hydrophobicity ionic liquid 1-butyl-3- methylimidazolium hexafluorophosphate (［C4mim］［PF6］) was synthesized with 1-methylimidazole and butylbromide and equimolar ammonium hexafluorophosphate, which was applied to preconcentration for trace gold. The factors which may affect preconcentration of gold were investigated. The experimental results showed that the absorbance was linear when the concentration of gold was in the range of 0.40~16.00μg·mL-1, with linear equation A = 0.007 63c +0.073 87(c:μg·mL-1), correlation coefficient r = 0.999 1, and detection limit 0.072 μg·mL-1. The method was applied to the determination of trace gold in water samples satisfactorily..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 260 (2011)
General Expression of Optic Path Difference of Reflecting Rotating Fourier Transform Spectrometer
ZHOU Jin-song, XIANGLI Bin, WEI Ru-yi, and JING Juan-juan
The principle of reflecting rotating Fourier transform spectrometer was introduced in the present paper. Based on the Malus law and reflecting characteristic of cube corner, the optic path difference of reflecting rotating Fourier transform spectrometer was analyzed and calculated by choosing the center of rotating mirThe principle of reflecting rotating Fourier transform spectrometer was introduced in the present paper. Based on the Malus law and reflecting characteristic of cube corner, the optic path difference of reflecting rotating Fourier transform spectrometer was analyzed and calculated by choosing the center of rotating mirror as a reference point of the aplanatic surface of incidence beam and return beam. General expression of optic path difference at any time and maximal optic path difference of reflecting rotating Fourier transform spectrometer was presented. The factors that influence the maximal optic path difference and the period of optic path difference were analyzed. The results provide a theoretical guidance for design and manufacture of reflecting rotating Fourier transform spectrometer..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 263 (2011)
Study on Photographing Experiment of Infrared Detector
WANG De-jiang, and ZHANG Tao
Infrared detectors are widely used in multi spectral remote sensing systems, and in order to verify photographing principles of infrared time delay integration (TDI) detector, and make preparations for future research, a verification system for infrared TDI camera is proposed in the present paper. Experimental methods Infrared detectors are widely used in multi spectral remote sensing systems, and in order to verify photographing principles of infrared time delay integration (TDI) detector, and make preparations for future research, a verification system for infrared TDI camera is proposed in the present paper. Experimental methods are explained thoroughly and two major factors which affect image quality are analyzed. First, the causes of image motion and their effects on the quality of image are studied, and a novel architecture using high precision DC-speed machine is presented, then the relationship between velocity of precision turntable and detectors line transfer frequency is determined by Kalman algorithm. Second, four focusing means are analyzed and compared, and video signal amplitude method is selected according to practical application. Finally, a genuine demo system is established in national supervision and test center for optics mechanics quality. 5.3, 6.4 and 9.2 mm drones are chosen for testing. Experimental results indicate that the obtained drone is vivid, and camera's resolution achieves 11.3 lines per mm, which satisfies preliminary aims..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 267 (2011)
Radiometric Calibration of LCTF-Based Multispectral Area CCD Camera
DU Li-li, YI Wei-ning, ZHANG Dong-ying, HUANG Hong-lian, QIAO Yan-li, and ZHANG Xie
Multispectral area CCD camera based on liquid crystal tunable filter (LCTF) is a new spectral imaging system, which could record image of one wavelength on the area CCD by utilizing electrically controlled birefringence of liquid-crystal and interference principle of polarized light. Because of the special working prinMultispectral area CCD camera based on liquid crystal tunable filter (LCTF) is a new spectral imaging system, which could record image of one wavelength on the area CCD by utilizing electrically controlled birefringence of liquid-crystal and interference principle of polarized light. Because of the special working principle of LCTF and frame transfer area CCD, the existing radiometric calibration method can not meet the precision need of remote sensing application if it is used for LCTF-camera. An improved radiometric calibration method is proposed, in which the camera performance test and calibration experiment are carried out relying on the devices of integrating sphere and standard detector, and the absolute calibration coefficient is calculated via correcting frame transfer smear and improving data process algorithm. Then the validity of the laboratory calibration coefficient is checked by a field validation experiment. Experimental result indicates that the calibration coefficient is valid, and the radiation information on the ground could be accurately inverted from the calibrated image data. With the resolution of radiometric calibration of LCTF-camera and the improvement of calibration precision, the application field of the image data acquired by the camera would be extended effectively..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 272 (2011)
High-Precision Measurement of Spherical Mirror Reflectivity in Vacuum Ultraviolet Spectrum
LI Bo, WANG Shu-rong, and HUANG Yu
In order to directly measure the vacuum ultraviolet spectrum reflectance of spherical mirror a measurement system was established. The system consists of monochromatic light source with deuterium lamp of magnesium fluoride window and Seya-Namioka concave grating monochromator, optical compensator with reflection modulaIn order to directly measure the vacuum ultraviolet spectrum reflectance of spherical mirror a measurement system was established. The system consists of monochromatic light source with deuterium lamp of magnesium fluoride window and Seya-Namioka concave grating monochromator, optical compensator with reflection modulator and reference detector and the receiving system with 80 mm diameter fluorescence integrating sphere and precision turntable. The optical compensation eliminates the instability in monochromatic light source, and the fluorescence integrating sphere eliminates the impact of light spot sizes in the two measurements, and reduce the system energy loss. The system measures the spherical mirror reflectivity in 115~180 nm, and the measurement result show that the repeatability is less than ±0.3%, and the relative uncertainty is less than 1.3%. The spherical mirror reflectivity achieves high-precision measurement..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 277 (2011)
Study on the Characteristics of the Imaging Spectrometer Calibration Using Diffuser Method
ZHANG Chun-lei, and XIANG Yang
Using a white diffuser to calibrate the imaging spectrometer has been a new technology developed to calibrate the imaging spectrometer recently. It has characteristics of easy realization and higher calibration accuracy. The expression of the collected signal electron number in each spectral channel of the imaging specUsing a white diffuser to calibrate the imaging spectrometer has been a new technology developed to calibrate the imaging spectrometer recently. It has characteristics of easy realization and higher calibration accuracy. The expression of the collected signal electron number in each spectral channel of the imaging spectrometer detector pixels was deduced with the slit parallel and perpendicular to the meridional plane according to the principal of the calibration of imaging spectrometer using diffuser method in the present paper. The spectral radiometric calibration characteristics of the imaging spectrometer was numerically analyzed under the two special slit directions. The results indicate that the slit direction has significant effect on the spectral radiometric calibration of the imaging spectrometer. The signal electron number of the same spectral channel collected by the different scene pixels is different when the slit parallels to the meridional plane, and when the pixel is closer to the standard lamp, it collects more signal electrons; the signal electron number of the same spectral channel collected by the different scene pixels doesn’t change with the scene pixel position when the slit is perpendicular to the meridional plane..
Spectroscopy and Spectral Analysis
- Publication Date: Sep. 29, 2021
- Vol. 31, Issue 1, 282 (2011)
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