Journals >Spectroscopy and Spectral Analysis
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2011
Volume: 31 Issue 2
66 Article(s)
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Research Article
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[in Chinese]
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 1 (2011)
[in Chinese]
[in Chinese]
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 289 (2011)
Validation of the Crystal Structure of Medicinal Realgar in China
ZHANG Zhi-jie, ZHOU Qun, WEI Jing-zhi, ZHANG Yan-ling, SUN Su-qin, HUANG Lu-qi, and YUAN Si-tong
The crystal structure of medicated realgar in China was validated as α-As4S4 by X-ray diffraction and Raman spectroscopy in the present paper. Ten batches of medicinal realgar were analyzed including realgar ore, medicinal realgar powder, and prepared Chinese medicine. Identification of two As4S4 polymorphs confirmed tThe crystal structure of medicated realgar in China was validated as α-As4S4 by X-ray diffraction and Raman spectroscopy in the present paper. Ten batches of medicinal realgar were analyzed including realgar ore, medicinal realgar powder, and prepared Chinese medicine. Identification of two As4S4 polymorphs confirmed that the crystal structure of medicated realgar in China is α-As4S4. Studies on 18 batches of preparative realgar powder showed that processing of realgar can not change the crystal structure of realgar..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 291 (2011)
Initial Research on Fourier Transform Infrared Spectroscopy for the Diagnosis of Colon Neoplasms
YAO Hong-wei, LIU Ya-qi, FU Wei, SHI Xue-ying, ZHANG Yuan-fu, and XU Yi-zhuang
To explore the feasibility of Fourier transform infrared spectrometry (FTIR) for the diagnosis of colon neoplasms, fresh samples of eighteen cancers and ten adenomas were collected during colon surgery and were measured by FTIR via probe of attenuated total reflection (ATR). The peak position and the intensity of all bTo explore the feasibility of Fourier transform infrared spectrometry (FTIR) for the diagnosis of colon neoplasms, fresh samples of eighteen cancers and ten adenomas were collected during colon surgery and were measured by FTIR via probe of attenuated total reflection (ATR). The peak position and the intensity of all bands were measured and compared between the malignant and benign groups. Results show that the FTIR of malignant neoplasm was different from that of benign one. (1)For the bands related to lipid: The ratio of I2 925/I1 460(p=0.018) and I1 740/I1 460(p=0.009) decreased in cancer FTIR spectrum, indicating the lower relative quantity of lipid in malignant neoplasm. (2)For the bands related to protein: The ratios of I3 375/I1 460(p=0.012) and I1 550/I1 460(p=0.041) increased in cancer, which shows that the relative quantity of protein was more in cancer than that in adenoma. (3) For the band related to nucleic acid: In malignant tissue the peak position in 1 080 cm-1 shifted toward a higher wave number (p=0.039), compared with that in benign one. And the ratio of I1 083/I1 460 increased significantly (p=0.036), illustrating the higher relative quantity of nucleic acid to lipids in malignancy. (4) The peak position of 1 305 cm-1 shifted to a lower wavenumber (p=0.041), which should be determined in further research. It is concluded that our initial research showed that the FTIR maybe develops into a promising method for rapid differential diagnosis of colon malignant and benign neoplasms..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 297 (2011)
In Vivo Reflectance Spectroscopy Study of Different Clearing Agents on Human Skin Optical Clearing
ZHAO Qing-liang, GUO Zhou-yi, WEI Hua-jiang, YANG Hong-qin, SI Jun-li, XIE Shu-sen, WU Guo-yong, ZHONG Hui-qing, LI Lan-quan, and GUO Xiao
The changes of skin tissue reflectance spectroscopy before and after being treated with the optical clearing agents of three different types of optical clearing within the wavelength rang of 400～1 000 nm, and the degree of changes in reflectance spectroscopy of each group skin during 0～60 min at 580 nm in vivo were reaThe changes of skin tissue reflectance spectroscopy before and after being treated with the optical clearing agents of three different types of optical clearing within the wavelength rang of 400～1 000 nm, and the degree of changes in reflectance spectroscopy of each group skin during 0～60 min at 580 nm in vivo were real-time dynamically researched. The reflectance spectroscopy of skin tissue before and after being dealt by the optical clearing agents of glycerol, glucose and propylene glycol was measured using a USB-4000 fiber spectrophotometer at 0, 10, 20, 30, 40, 50 and 60 min. The results showed that the reflectance spectral intensity was distinctly decreased, but the reflectance was significantly increased gradually with the time prolonged. However, different optical clearing agents have different clearing progress. The relative decrease of reflectance of palm skin tissue before and after being dealt by the optical agents of 40% glycerol, 40% glucose and 40% propylene glycol during 10, 20, 30, 40, 50 and 60 min at the wavelength 580 nm is 5%, 7%, 9%, 10%, 11% and 12%, 9%, 13%, 16%, 19%, 21% and 22%, and 14%, 22%, 29%, 32%, 34% and 35%, respectively. The significant improvement in light transmittance and enhancement of light penetration through tissue was demonstrated for all solutions. The effect and processes of optical clearing of skin tissue is not only closely related to the choosing of the clearing agent type, but also related to the treatment time with the skin tissue. The clearing progress of different type optical clearing agent showed the order of 40% propylene glycol, 40% glucose and 40% glycerol..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 302 (2011)
A Method of Obtaining Vibrational Dephasing Time of Molecular Multi-Vibrational Modes Simultaneously
WAN Hui, YIN Jun, YU Ling-yao, LIU Xing, QU Jun-le, LIN Zi-yang, and NIU Han-ben
In the present paper, the authors used the time-resolved coherent anti-Stokes Raman scattering (CARS) spectroscopy based on supercontinuum developed by ourselves to acquire simultaneously the molecular vibration spectrum and vibrational dephasing time of the molecular various vibrational modes. Using benzonitrile as thIn the present paper, the authors used the time-resolved coherent anti-Stokes Raman scattering (CARS) spectroscopy based on supercontinuum developed by ourselves to acquire simultaneously the molecular vibration spectrum and vibrational dephasing time of the molecular various vibrational modes. Using benzonitrile as the sample, the authors measured its vibrational relaxation processes at its five typical vibrational modes and obtained their vibrational dephasing time respectively. In the experiment, the authors also found the phenomenon that oscillations appear in the vibrational dephasing of plane bending vibration mode of benzene ring in benzonitrile, which was caused by superposition of the two adjacent normal vibrational modes excited simultaneously. After mixing benzonitrile with anhydrous ethanol, the authors also measured their vibrational dephasing time. This method is capable of monitoring the changes of the molecular characteristics and its micro-environment, therefore it will find widespread applications in biology, chemistry and materials science..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 314 (2011)
Effects of Experimental Parameters on Elemental Analysis of Aluminum Alloy by Laser-Induced Breakdown Spectroscopy
ZHU De-hua, NI Xiao-wu, CHEN Jian-ping, and ZHANG Hong-chao
Laser-induced breakdown spectroscopy (LIBS) has been used to detect the elements of 2519A aluminum alloy by Nd∶YAG laser in the present paper. The atomic spectral lines of Al and Cu were observed using a portable spectrometer. The impacts of lens-to-sample distance, probe angle, laser pulse energy, observation height aLaser-induced breakdown spectroscopy (LIBS) has been used to detect the elements of 2519A aluminum alloy by Nd∶YAG laser in the present paper. The atomic spectral lines of Al and Cu were observed using a portable spectrometer. The impacts of lens-to-sample distance, probe angle, laser pulse energy, observation height and ambient pressure on the line intensities were studied. The results show that all these experimental parameters have great influence on the precision of LIBS such as line intensity, signal to background ratio and repeatability. Finally, the best results can be observed by using the optimum experimental conditions..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 319 (2011)
Terahertz Spectroscopic Inspection and Analysis of Xylitol and D-Xylose
LIANG Cheng-sen, and ZHAO Guo-zhong
In the present paper, THz spectra of xylitol and D-xylose are measured at room temperature in the frequency region of 0.3～2.6 THz. The results show that characteristic absorption peak of D-xylose was found at 1.67, 1.96 and 2.46 THz, and those of xylitol at 1.62, 1.87 and 2.51 THz. At the same time, density functional In the present paper, THz spectra of xylitol and D-xylose are measured at room temperature in the frequency region of 0.3～2.6 THz. The results show that characteristic absorption peak of D-xylose was found at 1.67, 1.96 and 2.46 THz, and those of xylitol at 1.62, 1.87 and 2.51 THz. At the same time, density functional theory was applied to obtain the structure and vibration frequencies of the single molecules of two samples in THz region. The simulation results reveal that some of the absorption peaks result from the intra-molecular modes, while the others have to be attributed to intermolecular interaction or phonon modes..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 323 (2011)
Study on Homogeneity of Low-Pressure Air Dielectric Barrier Discharge by Optical Emission Spectrum
DONG Li-fang, WANG Shuai, LIU Wei-yuan, YANG Yu-jie, YUE Han, and XIAO Hong
In the present work, a uniform discharge in low-pressure air was obtained by a dielectric barrier discharge device. The spatial homogeneity of the plasma temperature was studied by optical emission spectrum. The vibrational temperature was calculated by second positive band C3Πu→B3Πg and the rotational temperature (gasIn the present work, a uniform discharge in low-pressure air was obtained by a dielectric barrier discharge device. The spatial homogeneity of the plasma temperature was studied by optical emission spectrum. The vibrational temperature was calculated by second positive band C3Πu→B3Πg and the rotational temperature (gas temperature) was calculated by N+2 first negative band B2Σ+u→X2Σ+g. It was found that the vibrational temperature decreases with the voltage increasing, while the rotational temperature increases. In addition, the fluctuation amplitudes of vibrational and rotational temperature of the plasma along diameter of the discharge area decrease with the voltage increasing, which indicates that the homogeneity of the plasma increases with the voltage increasing. These results are of great significance to the application of uniform discharge obtained in air dielectric barrier discharge for material processing..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 328 (2011)
Preparation and Luminescence of Down-Conversion Material β—NaYF4∶Tb3+, Yb3+
JIANG Gui-cheng, WEI Xian-tao, WANG Lin-xiang, WANG Xiao-chun, CHEN Yong-hu, and YIN Min
NaYF4∶Tb3+, Yb3+ down-conversion (DC) phosphors were synthesized by hydrothermal method. X-ray diffraction (XRD), photoluminescence (PL) and photoluminescence excitation (PLE) spectra were used to characterize the samples. Experiment results revealed that samples of NaYF4∶Tb3+, Yb3+ crystallized in hexagonal shape withNaYF4∶Tb3+, Yb3+ down-conversion (DC) phosphors were synthesized by hydrothermal method. X-ray diffraction (XRD), photoluminescence (PL) and photoluminescence excitation (PLE) spectra were used to characterize the samples. Experiment results revealed that samples of NaYF4∶Tb3+, Yb3+ crystallized in hexagonal shape without cubic shape. When the doping concentration of Tb3+and Yb3+ was altered, the lattice structure of samples did not change, indicating that the Tb3+ and Yb3+ ions are completely dissolved in the NaYF4 host lattice by substitution for the Y3+. The emission from 5D4→7F6(489 nm), 5D4→7F5(542 nm), 5D4→7F4(584 nm), and 5D4→7F3(619 nm) of Tb3+ ions was observed, in which the dominant emission was at 542 nm. With single Tb3+ doping, no near-infrared (NIR) emission was observed under excitation of 355 nm pulsed laser. However, while with Tb3+ and Yb3+ codoping, the NIR emission at around 950～1 100 nm from Yb3+(2F5/2→2F7/2) was observed under the same excitation. The dependence of the visible and NIR-emissions on Yb3+ doping concentration has been investigated. These results show that there is energy transfer process between Tb3+and Yb3+. Furthermore, it is a possible DC process through cooperative energy transfer from Tb3+ to Yb3+. When the doping concentration is 1% mol Tb3+ and 6% mol Yb3+ respectively, the intensity of NIR emission reaches its strongest..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 331 (2011)
Vibronic Coupling Parameters and Luminescent Properties of Bivalent Europium Ion Doped Alkaline Earth Thioaluminates
ZHANG Dong-pu, XUE Wei, YU Zhi-nong, ZHANG Ting, JIANG Yu-rong, LENG Jian, and KONG Xiang-jun
To obtain blue and green electroluminescent phosphor of high efficiency, vibronic coupling parameters and luminescent properties of MⅡAl2S4∶Eu materials were researched. Configuration coordinate model, which is the base of assessment, was introduced and assessing parameters were listed firstly. Photoluminescent (PL) anTo obtain blue and green electroluminescent phosphor of high efficiency, vibronic coupling parameters and luminescent properties of MⅡAl2S4∶Eu materials were researched. Configuration coordinate model, which is the base of assessment, was introduced and assessing parameters were listed firstly. Photoluminescent (PL) and electroluminescent (EL) properties of MⅡAl2S4∶Eu were compared and analyzed by the PL and EL spectra. Additionally, performances of MⅡAl2S4∶Eu phosphor materials were evaluated with the calculation of characteristic energy and unitless factors by PL spectra. According to the result of assessment and the comparison of CIE1931 color coordinates, it can be concluded that BaAl2S4∶Eu and CaAl2S4∶Eu are suitable for blue and green emitting phosphor. Mg and Sr thioaluminates can be used as parts of complex thioaluminate phosphors because they can shift the emission peaks..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 335 (2011)
Effect of Rubrene Position on the EL Performance of the Device and Analysis of the Exciton Recombination Zone
XU Deng-hui, LI Xiong, WANG Xiu-e, ZHAO Ci, ZHAO Jia, DENG Zhen-bo, L Zhao-yue, and CHEN Zheng
By using an ultrathin 5,6,11,12-tetraphenylnaphthacene (rubrene) layer deposited on the top of host materials， the influence of rubrene layer position on the electroluminescence (EL) spectra of organic light-emitting devices (OLEDs) was studied.When the rubrene layer is located at the interface between N,N’-diphenyl-N,By using an ultrathin 5,6,11,12-tetraphenylnaphthacene (rubrene) layer deposited on the top of host materials， the influence of rubrene layer position on the electroluminescence (EL) spectra of organic light-emitting devices (OLEDs) was studied.When the rubrene layer is located at the interface between N,N’-diphenyl-N,N’-bis(1-naphthyl)-(1,18-biphenyl)-4,4’-diamine (NPB) and tris(8-hydroxyquinoline) aluminum (AlQ) layer, EL luminescence of the device is nearly coming from rubrene emission. From the analysis of the EL spectra of the devices with different rubrene layer position, the solely contribution of rubrene and AlQ, respectively, to the luminescence of the devices is determined by spectra unmixing. Based on the analysis, the exciton length in AlQ layer is determined to be about 15-20 nm. The exciton transport and recombination characteristics are also discussed in this work..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 340 (2011)
Modification and Luminescence Properties of Transparent Lu2SiO5∶Ce3+ Thin-Film Phosphors
FAN Yang-yang, LIU Xiao-lin, GU Mu, NI Chen, HUANG Shi-ming, and LIU Bo
To achieve high-spatial-resolution for X-ray imaging and flat panel display, transparent thin-film phosphors have been attracted much attention in recent years. In comparison with conventional powder phosphors, the transparent thin-film phosphors have some outstanding advantages such as high contrast and resolution, suTo achieve high-spatial-resolution for X-ray imaging and flat panel display, transparent thin-film phosphors have been attracted much attention in recent years. In comparison with conventional powder phosphors, the transparent thin-film phosphors have some outstanding advantages such as high contrast and resolution, superior thermal conductivity and better adhesion. Cerium-doped lutetium oxyorthosilicate Lu2SiO5 (LSO) is one promising candidate due to its high density (7.4 g·cm-3), high light yield (27 300 photons·MeV-1), short decay time (40 ns), and excellent chemical stability. The sol-gel method is one of the most important techniques for deposition of functional thin films, because it possesses a number of advantages over conventional film formation techniques, such as low processing temperature, easy coating of large surfaces, homogenous multicomponent films, and cheap equipments. In X-ray imaging application, the thickness of the thin-film phosphor is the most important factor, which can increase X-ray absorption of the film and then strengthen its luminescence intensity. In the present work, transparent LSO∶Ce film was successfully prepared using sol-gel method and spin-coating technique by using inorganic salts as raw materials, 2-methoxyethanol as solvent， and poly (ethylene glycol) (PEG) as modifier without inert atmosphere. The effect of PEG on the luminescence properties of the film was investigated in detail. The results indicated that PEG200 played an important role in the formation of LSO∶Ce film, improving its quality and luminescent intensity. The film thickness of 0.9 μm was achieved after 5 times of coating. The luminescence properties of the film were studied. Their performances were good, which implied that the film would have promising applications in high-spatial-resolution X-ray imaging and flat panel display devices..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 344 (2011)
Luminescence Properties of Thenardite Activated with Tm3+ under Vacuum Ultraviolet Excitation
Taximaiti Yusufu, Ajimu Abulai, Keyoumu Niyazi, SU Zong-cai, and Aierken Sidike
The Na2SO4∶Tm3+ phosphor was synthesized by the high temperature solid state reaction method in air. The crystalline structure was examined by X-ray diffraction (XRD). Narrow bands observed in emission spectra were well identified with the electronic transitions within the 4f12 configurations of Tm3+, and the excitatioThe Na2SO4∶Tm3+ phosphor was synthesized by the high temperature solid state reaction method in air. The crystalline structure was examined by X-ray diffraction (XRD). Narrow bands observed in emission spectra were well identified with the electronic transitions within the 4f12 configurations of Tm3+, and the excitation spectrum is consisted of strong bands assigned to the 4f12→4f11 5d transition at 183 nm, the O2--Tm3+ charge transfer band at 170 nm and weak bands assigned to host absorption (130, 223 and 258 nm). In addition, the authors also found that the content of Tm3+ in the 8～16 mg concentration range caused quenching..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 349 (2011)
Study on the Meningoima Using FT-Mid-IR Spectroscopy
WAN Wei-qing, PAN Qing-hua, JIA Gui-jun, XU Yi-zhuang, LAI Guo-qiao, LIU Shao-xuan, CHEN Jing, YANG Li-min, ZHANG Yuan-fu, WENG Shi-fu, and WU Jin-guang
In the present investigation, 24 cases of meningoima tissues (including 12 cases of benign tumor and 12 cases of malignant tumor 12) were detected using FT-mid-IR spectroscopy linked with attenuated total reflectance (ATR) accessory. These FTIR spectra obtained from the above-mentioned meningoima tissues were analyzed In the present investigation, 24 cases of meningoima tissues (including 12 cases of benign tumor and 12 cases of malignant tumor 12) were detected using FT-mid-IR spectroscopy linked with attenuated total reflectance (ATR) accessory. These FTIR spectra obtained from the above-mentioned meningoima tissues were analyzed and compared. Significant differences were found in the spectral features of different kinds of meningoima tissues for example fibrous type meningoima and endothelioid meningoima; and for the same type of meningoima tissues the significant differences in the spectram features can be also observed with the increase of grade malignancy. The malignant tumor can be distinguished primarily from benign tumor by the changes of position, shape and intensity of infrared absorption bands, particularly in the ranges of 1 000～1 500 cm-1. The results show that the peak position of the bands (such as 1 160 cm-1) can be used to distinguish the characteristic of meningoima which are in agreement with the pathological results. The accuracy is larger than 85%. These results demonstrate that FT-mid-IR spectroscopy exhibits prospect to develop a novel, non-invasive and rapid method for the diagnosis the brain tumors..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 353 (2011)
Monitoring Method of Underground Coal Fire Based on Night Thermal Infrared Remote Sensing Technology
JIANG Wei-guo, WU Jian-jun, GU Lei, YANG Bo, CHEN Qiang, and LIU Xiao-chen
Land surface temperature is higher in the zones of underground coal fire than in their surroundings areas. It is possible to monitor the coal fire and the heat anomalies using the remote sensing technology of thermal infrared. By taking the coal fire of Wuda in Inner Mongolia Autonomous Region as an example，the monitorLand surface temperature is higher in the zones of underground coal fire than in their surroundings areas. It is possible to monitor the coal fire and the heat anomalies using the remote sensing technology of thermal infrared. By taking the coal fire of Wuda in Inner Mongolia Autonomous Region as an example，the monitoring methods of underground coal fire were explored based on different seasons night ASTER thermal infrared images. By employing the TES-ADE algorithm and threshold segmentation method，land surface temperature was retrieved and coal fire areas were extracted. Finally the seasonal variation of surface temperature，the surface temperature differences between night and day，and the change and distribution of coal fire area were analyzed. The results showed that (1) it is effective to retrieve land surface temperature and to avoid the interference of sand, bare land and building based on the remote sensing of thermal infrared at night; (2) it is best time to extract the coal fire areas based on the winter night images of thermal infrared; (3) it is effective to monitor the change and distribution of coal fire areas based on the winter night images of thermal infrared..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 357 (2011)
Influence of Improved Kennard/Stone Algorithm on the Calibration Transfer in Near-Infrared Spectroscopy
LI Hua, WANG Ju-xiang, XING Zhi-na, and SHEN Gang
The Kennard/Stone(K/S) algorithm is adopted to select the transfer set samples in the near infrared analysis calibration transfer by calculating the Euclidean distance of the spectrum of the samples. In order to get a best expression of the comparability of the samples and select the best samples for calibration transfThe Kennard/Stone(K/S) algorithm is adopted to select the transfer set samples in the near infrared analysis calibration transfer by calculating the Euclidean distance of the spectrum of the samples. In order to get a best expression of the comparability of the samples and select the best samples for calibration transfer, piecewise direct standardization (PDS) algorithm was investigated for resolving calibration transfer of near-infrared spectra of mixed amine, then the Euclidean distance and the Mahalanobis distance were applied to calculate the comparability of the spectra of the samples and the standard error of prediction (SEP) was used to evaluate them. The combination of spectral difference and property difference was introduced to estimate the effect of individual spectral difference and property difference. The experimental results showed that the Mahalanobis distance was better than the Euclidean distance in PDS and the combination of spectral difference and property difference was more effective in expressing the comparability of the samples..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 362 (2011)
Determination of Crystallinity in Neosinocalamus affinins Based on Near Infrared Spectroscopy and PLS Methods
SUN Bai-ling, LIU Jun-liang, and CAI Yu-bo
Near infrared spectroscopy technique combined with chemometrics methods was applied to predict crystallinity of Neosinocalamus affinins. Three improved partial least squares (PLS) methods, including interval partial least squares (iPLS), synergy interval partial least squares (siPLS) and backward interval partial leastNear infrared spectroscopy technique combined with chemometrics methods was applied to predict crystallinity of Neosinocalamus affinins. Three improved partial least squares (PLS) methods, including interval partial least squares (iPLS), synergy interval partial least squares (siPLS) and backward interval partial least squares (biPLS), were used to find the most informative ranges and build models with better predictive quality based on multiplicative scatter correction spectra. And then the models were compared with PLS model which was developed on the whole wavelength range 350~2 500 nm. The results showed that the models built by the three improved PLS methods had higher predictive ability than that of PLS model, and the optimal model was obtained by siPLS method that separated the whole spectra into 30 intervals and combined three intervals. The siPLS model had correlation coefficient (R) of 0.88 and root mean standard error of prediction (RMSEP) of 0.011 7. Therefore, through selecting the effective wavelength range, siPLS method could accurately and rapidly predict crystallinity in Neosinocalamus affinins..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 366 (2011)
Comparison of Methods for Estimating Soybean Chlorophyll Content Based on Visual/Near Infrared Reflection Spectra
TANG Xu-guang, SONG Kai-shan, LIU Dian-wei, WANG Zong-ming, ZHANG Bai, DU Jia, ZENG Li-hong, JIANG Guang-jia, and WANG Yuan-dong
The estimation of crop chlorophyll content could provide technical support for precision agriculture. Canopy spectral reflectance was simulated for different chlorophyll levels using radiative transfer models. Then with multiperiod measured hyperspectral data and corresponding chlorophyll content, after extracting six The estimation of crop chlorophyll content could provide technical support for precision agriculture. Canopy spectral reflectance was simulated for different chlorophyll levels using radiative transfer models. Then with multiperiod measured hyperspectral data and corresponding chlorophyll content, after extracting six wavelet energy coefficients from the responded bands, an evaluation of soybean chlorophyll content retrieval methods was conducted using multiple linear regression, BP neural network, RBF neural network and PLS method. The estimate effects of the three methods were compared afterwards. The result showed that the three methods based on wavelet analysis have an ideal effect on the chlorophyll content estimation. R2 of validated model of multiple linear regression, BP neural network, RBF neural network and PLS method were 0.634, 0.715, 0.873 and 0.776, respectively. PLS based on Gaussian kernel function and RBF NN methods were better with higher precision, which could estimate chlorophyll content stably..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 371 (2011)
Study on Measurement of Cholesterol in Serum by Near-Infrared Spectroscopy and Applicability of Models
YANG Hao-min, and LU Qi-peng
To study rapid analysis of cholesterol concentration in human serum with no reagent, near-infrared spectroscopy was used. Applicability of analytical models was studied. Spectra of serum were measured by a FT-NIR spectrometer with 1, 2 and 6.5 mm optical path length respectively. Partial least-square (PLS) models were To study rapid analysis of cholesterol concentration in human serum with no reagent, near-infrared spectroscopy was used. Applicability of analytical models was studied. Spectra of serum were measured by a FT-NIR spectrometer with 1, 2 and 6.5 mm optical path length respectively. Partial least-square (PLS) models were calibrated for cholesterol in combination, first overtone and second overtone spectral regions. Root mean square error of prediction (RMSEP) of these models is 0.15, 0.16 and 0.29 mmol·L-1, and mean percent error of prediction (MPEP) is 2.9%, 3.1% and 4.8%, respectively. To validate applicability of these models, other two groups of serum spectra were measured in one month after the models were calibrated. These two sample groups were calculated using calibrated models. Prediction result of 1mm model is the best. The result of this experiment indicates tha.
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 375 (2011)
Research on Prediction Chemical Composition of Beef by Near Infrared Reflectance Spectroscopy
SUN Xiao-ming, LU Ling, ZHANG Jia-cheng, ZHANG Song-shan, and SUN Bao-zhong
This study established a near infrared reflectance spectroscopy models for exactly predicting the fat, protein and moisture of the ground and mince beef on line. Using our country’ SupNIR-1000 near infrared spectrometer, the models were set up by artificial neural network (ANN). Related coefficient of calibration (rC) This study established a near infrared reflectance spectroscopy models for exactly predicting the fat, protein and moisture of the ground and mince beef on line. Using our country’ SupNIR-1000 near infrared spectrometer, the models were set up by artificial neural network (ANN). Related coefficient of calibration (rC) of fat model of mince was 0.971 and related coefficient of prediction (rP) was 0.972.The protein’ rC and RP were 0.952 and 0.949, respectively. The moisture’ rC and rP were 0.938 and 0.927, respectively.Using ground beef established models, the fat’ rC and rP were 0.935 and 0.810; the protein’ rC and rP were 0.954 and 0.868; the moisture’ rC and rP were 0.930 and 0.913, respectively. So near infrared reflectance spectroscopy can better detect the fat, protein and moisture of mince than ground beef. But basically the ground beef model also can be used to quickly predict the chemical composition on line..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 379 (2011)
Detection Technology of Methane Gas Concentration Based on Infrared Absorption Spectrum
LUO Da-feng, YANG Jian-hua, and ZHONG Chong-gui
According to the disadvantages of current methane sensor in coal mine, the infrared methane concentration detection system based on the principle of infrared spectrum absorption was designed using differential absorption technology. In the system single light beam absorbing cell and single light beam and double wavelenAccording to the disadvantages of current methane sensor in coal mine, the infrared methane concentration detection system based on the principle of infrared spectrum absorption was designed using differential absorption technology. In the system single light beam absorbing cell and single light beam and double wavelengths technology are adopted. Differential amplifier circuit serves as the core of faint signal processing circuit that detects the output signal of methane concentration, and linear formula fits the curve of methane concentration and output voltage, which realizes accurate and full range detection of gas concentration. Experiment shows that measurement error is less than 2%, and the system has very high measurement precision and possesses the basis of industrial applications..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 384 (2011)
Application of Vis／NIR Diffuse Reflectance Spectroscopy to the Rapid Detection and Identification of Tomato Fruit via Space Mutation Breeding
SHI Jia-hui, CHEN Zi-li, SHAO Yong-ni, HE Yong, FENG Pan, and ZHU Jia-jin
In order to quickly analyze varieties of tomato via space mutation breeding with near infrared spectra, characteristics of the pattern were analyzed by partial least square. The model was built with radial basis function neural network and regarded the compressed data as the input of neural network input vectors. The mIn order to quickly analyze varieties of tomato via space mutation breeding with near infrared spectra, characteristics of the pattern were analyzed by partial least square. The model was built with radial basis function neural network and regarded the compressed data as the input of neural network input vectors. The model regarded the compressed data as the input of neural network input vectors and the training process was speeded up. For one hundred and five fruit samples of CK, M1 and M2 the training model was built. Forty five samples formed the prediction set. The discrimination rate of these two models achieved 95.6% and 97.8%. It offered a new approach to the fast discrimination of varieties of tomato via space mutation breeding..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 387 (2011)
The Application of Near-Infrared Diffuse Reflection Spectra Based on the Principle of Linear Additive in Tobacco Redrying Formula
ZHANG Ya-juan, MA Xiang, ZHANG Ye-hui, MI Jin-rui, XU Li, WANG Yi, WEN Ya-dong, ZHAO Long-lian, LI Jun-hui, and ZHANG Lu-da
In the process of analyzing and designing tobacco redrying formula using near infrared spectroscopy, a great deal of spectra for different ratio mixed samples are badly needed. However these sample spectra are very hard to obtain in the actual production process. Furthermore, for the samples of different grades it is dIn the process of analyzing and designing tobacco redrying formula using near infrared spectroscopy, a great deal of spectra for different ratio mixed samples are badly needed. However these sample spectra are very hard to obtain in the actual production process. Furthermore, for the samples of different grades it is difficult to achieve the goal of even mixing, in consequence of introducing inevitable errors. In order to solve the above problems, the present paper proposes to use “theory of even mixed spectrum” produced by linear additive near infrared spectroscopy in place of the spectra of actual mixed samples. This way can not only eliminate the errors caused by uneven mixture, but also leave out the course of mixing samples and measuring spectra and save time, effort, and material simultaneously. This article analyzes the comparison between linear additive spectra and the spectra of actual mixed samples from the following four aspects: original spectra, derivative spectra, principal components, and the data of PPF projection, accordingly verifing the feasibility and superiority of the linear additive spectra..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 390 (2011)
Fabrication of Reproducible Surface Enhanced Raman Scattering Substrate and Its Application
NI Dan-dan, WANG Wei-wei, YAO Jian-lin, ZHANG Xue-jiao, and GU Ren-ao
Gold nanoparticles were homogeneously coated with silica using the silane coupling agent (3-aminopropyl)-trimethoxysilane to functionalize the gold surface and sodium silicate solution as the precursor of silica. The shell thickness could be well controlled by changing the amount of sodium silicate, reaction temperaturGold nanoparticles were homogeneously coated with silica using the silane coupling agent (3-aminopropyl)-trimethoxysilane to functionalize the gold surface and sodium silicate solution as the precursor of silica. The shell thickness could be well controlled by changing the amount of sodium silicate, reaction temperature and time. The Au@SiO2 core-shell nanoparticles with a suitable silica shell thickness exhibited optimal SERS activity and were self-assembled onto an ITO substrate in order to get a stable and reproducible SERS substrate. The conditions for preparing SERS substrates can be optimized by investigating the relationship between the intensity of SERS signals and the thickness of silica shell. The reproducible SERS measurements were performed by using 1,4-BDT and 4,4’-bipyridine as probe molecules. Within a certain concentration range, the linear relationship between the SERS intensities and the logarithm of concentration was obtained. The results revealed that the Au@SiO2 substrate assembled on ITO surface could be developed as a reproducible substrate for the quantitative analysis..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 394 (2011)
In-situ Raman Spectroscopic Study of Serpentine Using Diamond Anvil Cell
LIU Jin, and SUN Qiang
Within the diamond anvil cell, the Raman spectroscopic study of serpentine was operated at room temperature and under pressures from 1 atm to 5 140 MPa. This study analyzed the pressure dependence of the low-frequency Raman vibrational modes of sepentine at 388, 471, 692 and 705 cm-1 respectively. The vibrational modesWithin the diamond anvil cell, the Raman spectroscopic study of serpentine was operated at room temperature and under pressures from 1 atm to 5 140 MPa. This study analyzed the pressure dependence of the low-frequency Raman vibrational modes of sepentine at 388, 471, 692 and 705 cm-1 respectively. The vibrational modes of inner OH groups at 3 664 cm-1 and inter-layer OH groups at 3 696 cm-1 shifted linearly with the increasing pressures. The pressure-related slope of 3 664 cm-1 was 3.3 cm-1·GPa-1. The vibrational mode at 3 696 cm-1 of the inter-layer hydroxyl shifted upwards with the pressure-related slope 8.3 cm-1·GPa-1 up to 2.0 GPa, and then with 1.1 cm-1·GPa-1 from 2.0 GPa to ca. 5.0 GPa. It could be interpreted that the hydrogen bond of the inter-layer hydroxyl made dominant contribution to such experimental phenomena. In addition, the dehydration of serpentine did not occur under such conditions..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 398 (2011)
Experimental Study on Raman Spectroscopy of Alkane Gases in Simulated Deep-Sea Extreme Environments
MA Jun, QU Ye-fei, HUANG Yang-yu, YANG Cheng-en, SHI Xiao-feng, and ZHENG Rong-er
In the present work, Raman spectra of alkane gases aqueous solution under simulated deep-sea hydrothermal environment were acquired by high temperature and high pressure deep-sea simulation experiment system. The variation laws of the Raman spectral features with various temperature and pressure were analyzed and matheIn the present work, Raman spectra of alkane gases aqueous solution under simulated deep-sea hydrothermal environment were acquired by high temperature and high pressure deep-sea simulation experiment system. The variation laws of the Raman spectral features with various temperature and pressure were analyzed and mathematical model between them were established. The results show that for all Raman peaks of these alkane gases in aqueous solution the frequency is lower than gaseous state because of hydrogen bond; the variations of their Raman spectrum were not obvious as the pressure increased (≤40 MPa) in room temperature; and all peak positions move to lower wave number and their full width at half maximum (FWHM) increased along with changing temperature in the range of room temperature to 350 ℃ at 40 MPa pressure. The results provide an experimental basis for the in-situ detection of deep sea by Raman laser spectroscopy system in hydrothermal environment..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 402 (2011)
Study of Spectrum Processing Method for Raman Microscopy on Single Living Cell
KANG Li-li, HUANG Yao-xiong, and WU Zheng-jie
To study the spectrum processing methods for Raman microscopy on single living cell and develop the pre-process techniques for Raman spectrum of single living cell to enhance the signal to noise ratio, sensitivity, and decrease the fluorescence influence, wiping off the cosmic rays was used to improve the spectrum. TheTo study the spectrum processing methods for Raman microscopy on single living cell and develop the pre-process techniques for Raman spectrum of single living cell to enhance the signal to noise ratio, sensitivity, and decrease the fluorescence influence, wiping off the cosmic rays was used to improve the spectrum. The spectra classification, spectra average and filtration were applied to enhance signal to noise ratio. The fluorescence was depressed for quantity analysis or utilized for analysis by comparing the background and the spectra. Results show that (1) comparing the spectra with short exposure time and more scans can wipe off the cosmic rays effectively. (2) the spectra classification, spectra average and filtration can improve the quality of spectra and can show some weak and sensitive bands. (3)sometimes the fluorescence has useful information. It is concluded that the proposed techniques for Raman spectrum of single cell in this paper can show the sensitive and weak intensity peaks and reflect the information of molecules structures very well..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 408 (2011)
Analysis of Components Difference of Yeast Strains Based on Laser Tweezers Raman Spectroscopy Combined with Multistatistical Analysis
LAI Jun-zhuo, LIU Bin, WANG Gui-wen, TAO Zhan-hua, and HUANG Shu-shi
The combination of laser tweezers and con-focusing Raman spectroscopy (LTRS) has made it possible to investigate single cells in aqueous media. In our experiments, a modified method of Percoll density gradient centrifugation was developed for isolating synchronous cells from six yeast strains and Raman spectra of singlThe combination of laser tweezers and con-focusing Raman spectroscopy (LTRS) has made it possible to investigate single cells in aqueous media. In our experiments, a modified method of Percoll density gradient centrifugation was developed for isolating synchronous cells from six yeast strains and Raman spectra of single yeast cells were collected by LTRS as well, in which multiple statistical analysis, principal component analyses (PCA) and discriminant function analysis (DFA) were applied to distinguish synchronous cells between yeast strains statistically. The result showed that Raman spectra scattered from the trapping yeast cells could provide intrinsic molecular information, and there were remarkable difference among those of six yeast strains in Raman spectrogram which correspond to various biomacromolecule, the difference of protein as well as lipid were significantly higher than nucleinic acid between two of yeast strains randomly, and among the six strains, synchronized yeast cells can be discriminated using PCA and DFA based on 14 most contribution bands, 706, 862, 918, 997, 1 073, 1 127, 1 269, 1 291, 1 305, 1 429, 1 465, 1 591, 1 602 and 1 652 cm-1, 10 bands of which were from protein， 3 bands were from lipoid, and 1 band was from nucleinic acid. To validate their significance, these variables were used to reperform DFA analysis and the re-plotted PC-DFA was the same as in the previous PC-DFA analysis, and the data would be considered validated. The authors show that the approach of laser tweezers Raman spectroscopy combined with multistatistical analysis has the potential to study difference among yeast strains..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 412 (2011)
Laser Tweezers Raman Spectroscopy Analysis of Cold-Adapted Aromatic Hydrocarbons-Degradating Strains Isolated from Antarctic Sea
WANG Yi-bin, MIAO Jin-lai, HE Bi-juan, LIANG Qiang, LIU Fang-ming, and ZHENG Zhou
Laser tweezers Raman spectroscopy can help with observing and studying individual cells or organelles in a natural state for a relatively long period. In the present experiment, Laser tweezers Raman spectroscopy (LTRS) was used as a tool to report physiological metabolism such as cells growth and nucleic acid, proteinsLaser tweezers Raman spectroscopy can help with observing and studying individual cells or organelles in a natural state for a relatively long period. In the present experiment, Laser tweezers Raman spectroscopy (LTRS) was used as a tool to report physiological metabolism such as cells growth and nucleic acid, proteins, lipid and glucose of a single active cold-adapted Aromatic hydrocarbons-degradating strains isolated from Antarctic Sea. After the Raman spectrum was collected and analyzed, the findings are as follows: Raman spectrum identified the components of a single cold-adapted Aromatic hydrocarbons-degradating strain and there were more proteins and carbohydrate produced during the Planococcus sp.NJ41 and Shewanella sp.NJ49 growth and degradation; but there was more lipid than the proteins produced during the Pseudoalteromonas sp.NJ289 growth and degradation; the amount of proteins produced by the strains corresponds with the production of degradation rate-limiting enzyme, and was also related to the capacity of low-temperature degradation of aromatic hydrocarbons..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 418 (2011)
The Study on the UV and Fluorescence Properties of PAMAM Dendrimers
LI Ya-peng, ZHAO Yi-li, SONG Yan-tao, CHANG Yu-lei, and LIU Lin-lin
From 0.5 to 5.0 generation PAMAM dendrimers were synthesized with ethylenediamine core by Michael addition reaction and aminolysis reaction two repeated steps. The structure of dendrimers were confirmed by FTIR 1H NMR 13C NMR MS and all of these measurements showed that they were successfully synthesized. Furthermore, From 0.5 to 5.0 generation PAMAM dendrimers were synthesized with ethylenediamine core by Michael addition reaction and aminolysis reaction two repeated steps. The structure of dendrimers were confirmed by FTIR 1H NMR 13C NMR MS and all of these measurements showed that they were successfully synthesized. Furthermore, The authors studied the UV and fluorescence properties of different generation dendrimers. Because of diffenent terminal groups,it was found that the whole generation and half generation show different ultraviolet absorption peaks and the intensityof ultraviolet absorption is closely related to the molecular skeleton. There is no traditional fluorescence emission groups, but PAMAM dendrimers show the peculiar phenomenon. In this paper we detailedly studied the factors which affect PAMAM dendrimers fluorescence properties..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 422 (2011)
Parallel Factor Analysis for Excitation Emission Matrix Fluorescence Spectroscopy of Dissolved Organic Matter from a Reservoir-Type River
GUO Wei-dong, YANG Li-yang, WANG Fu-li, CHEN Wen-zhao, WANG Xin-hong, and HONG Hua-sheng
The fluorescent components and their distribution and variation of dissolved organic matter (DOM) were examined using excitation emission matrix fluorescence spectroscopy-parallel factor analysis technique (EEMs-PARAFAC) for samples collected during June, 2008 from Minjiang River, a typical subtropical reservoir-type rThe fluorescent components and their distribution and variation of dissolved organic matter (DOM) were examined using excitation emission matrix fluorescence spectroscopy-parallel factor analysis technique (EEMs-PARAFAC) for samples collected during June, 2008 from Minjiang River, a typical subtropical reservoir-type river ecosystem. Three separate fluorescent components were identified by PARAFAC, including two dominant humic-like components (C1: <250, 325/424 nm; C2: 270, 395/482 nm) and one protein-like component (C3: <250, 280/358 nm), of which humic-like components were dominant. Fluorescence analysis provided a ‘fingerprint’ technique to trace the mixing of DOM between three tributaries in the upstream of Minjiang River. The nearly constant concentration and composition in the main stream of Minjiang River reflected the effect of dam construction. Correlation and principal component analysis (PCA) revealed that humic-like components were principally derived from flushing of watershed soils, while protein-like component was formed from in-situ production which could be used as a proxy of the concentration of total dissolved nitrogen (TDN). Multi-linear regression of fluorescent components C2 and C3 can be used to trace the variation of dissolved organic carbon (DOC) concentration. This study demonstrates that Minjiang is a typical subtropical reservoir-type river which still keeps relatively ‘unpolluted’ aquatic environment..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 427 (2011)
The Excimer of Thioflavin T Induced by Polyelectrolyte and Its Fluorescence Ratiometric Sensing for Temperature
LI Dan, SUN Xiang-ying, and LI Fang
In the present paper, the authors studied the effects of anionic polyelectrolyte sodium polystyrene sulfonate (PSS) on the cationic dye thioflavin T (ThT) fluorescence spectra in aqueous solution. The influencing factors of the formed thioflavin T excimer in the existence of PSS were investigated. Experimental results In the present paper, the authors studied the effects of anionic polyelectrolyte sodium polystyrene sulfonate (PSS) on the cationic dye thioflavin T (ThT) fluorescence spectra in aqueous solution. The influencing factors of the formed thioflavin T excimer in the existence of PSS were investigated. Experimental results show that PSS could increases the local concentration of ThT by electrostatic attraction, therefore enhances excimer formation of thioflavin T. The fluorescence intensity of ThT monomer and excimer (IM and IE) changes regularly along with the change in temperature; ln(IE/IM) and 1/T have good linear relationship. Hereby we have developed a new type of fluorescence ratiometric sensor for temperature which could be recognized by naked eye, and it could effectively eliminate environmental effects such as instability of exciting light intensity and photobleaching， therefore improve the accuracy of identification..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 431 (2011)
Synthesis and Photoluminescence of Novel Terbium(Ⅲ) Ternary Complexes with Carboxylic Acid
REN Xiao-ming, WEI Chang-ping, and L Zhi-jun
In the present paper, imidazo［5,6-f］ phenanthroline(IP), 2-aniline carbonyl benzoic acid (HAB) and 2-diphenylamine carbonyl benzoic acid(HDPAB) were synthesized at room temperature. Under the same condition, with HAB and HDPAB as the first ligand and IP as the secondary ligand, two novel ternary organic terbium complexIn the present paper, imidazo［5,6-f］ phenanthroline(IP), 2-aniline carbonyl benzoic acid (HAB) and 2-diphenylamine carbonyl benzoic acid(HDPAB) were synthesized at room temperature. Under the same condition, with HAB and HDPAB as the first ligand and IP as the secondary ligand, two novel ternary organic terbium complexes were prepared in ethanol solution. Elemental analysis demonstrated that the chemical formula of the two ternary complexes were Tb(HAB)3IP and Tb(HDPAB)3IP. The spectroscopic properties of the ligands and complexes were also discussed. IR spectra indicated that rare earth Tb3+ ion was coordinated with oxygen atoms of the first ligand HAB and HDPAB and two nitrogen atoms of the secondary ligand IP. The UV spectra showed that the main absorption was from the first ligand in the ternary complexes, the secondary ligand was bonded to rare earth Tb3+ ion and the energy transfer efficiency of HAB was higher than that of HDPAB. The excitation and emission spectra of the two terbium complexes were measured and investigated, especially by comparing their fluorescence intensities. Fluorescence spectra demonstrated that the two kinds of ternary organic terbium complexes could emit characteristic fluorescence of rare earth Tb3+ ion. But the fluorescence intensity of Tb(HAB)3IP was obviously higher than that of Tb(HDPAB)3IP. Compared with two first ligands HDPAB and HAB, the fluorescence intensities of the two ternary organic terbium complexes were found to be influenced by the molecule structure, and the benzene ring which was coordinated with nitrogen atom increased in HDPAB. In the system of ternary complexes, due to the different coordinated number of benzene ring, the mobility of electron and the distribution of electron cloud were changed. The variation affected the transition of the π electrons, which can take in the energy in ternary complexes. So, the energy transfer efficiency from the first ligand to rare earth Tb3+ ion decreased and Antenna effect achieved inefficiency in Tb(HDPAB)3IP..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 436 (2011)
The Surface Smoothing Methods for Three-Dimensional Fluorescence Spectrometry Based on Savitzky-Golay Polynomial Smoothing
DU Shu-xin, DU Yang-feng, and WU Xiao-li
Spectral smoothing is commonly used as effective pretreatment methods in the spectral analysis. However, the conventional Savitzky-Golay polynomial smoothing methods used in two-dimensional spectral analysis can not be applied to three-dimensional spectrometry directly. In the present paper, a polynomial surface smoothSpectral smoothing is commonly used as effective pretreatment methods in the spectral analysis. However, the conventional Savitzky-Golay polynomial smoothing methods used in two-dimensional spectral analysis can not be applied to three-dimensional spectrometry directly. In the present paper, a polynomial surface smoothing method is proposed, and the two-dimensional Savitzky-Golay polynomial smoothing methods are extended to three-dimensional fluorescence spectra. Experiment for detecting dissolved organ matter in water using three-dimensional florescence spectrometry was carried out, and experimental results show that the smoothing method for the three-dimensional fluorescence spectrum can effectively improve the modeling accuracy..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 440 (2011)
Determination of Protein by CdS Quantum Dot Fluorometry
HU Wei-ping, JIAO Man, DONG Xue-zhi, and WANG Xin
Determination of protein content by fluorometry was carried out. In this experiment, CdS quantum dots(QDs)that have special spectral properties were prepared with sodium hexametaphosphate as stabilizer and mercapto acetic acid as modifier by hydrothermal synthesis method. Based on the increase in fluorescence intensityDetermination of protein content by fluorometry was carried out. In this experiment, CdS quantum dots(QDs)that have special spectral properties were prepared with sodium hexametaphosphate as stabilizer and mercapto acetic acid as modifier by hydrothermal synthesis method. Based on the increase in fluorescence intensity after CdS reacted with bovine serum albumin (BSA), a new method for the determination of protein was established. Results show that the fluorescence intensity of system has a good linear relationship with the concentration of BSA in the range of 0.001 43～0.250 mg·mL-1, and the linear equation was F=5 444.301 03+43.327 39ｃ, relation coefficient (r) was 0.996 6, the limit of detection was 0.001 4 mg·mL-1. The method has been used for the determination of protein in milk and egg, and compared with the standard method (biuret method), and the results were satisfactory..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 444 (2011)
Study on the Fluorescence Resonance Energy Transfer between CdTe QDs and Rhodamine B and Its Application to the Determination of Trace Amount of Copper in Flos Lonicerae Japonicae
WANG Xiao-mei, YE Chao, LI Chen-gui, and HU Yu-zhu
The present work is to find the optimum condition for fluorescence resonance energy transfer between CdTe QDs (donor) and rhodamine B (acceptor) and form a new method to detect copper in Flos Lonicerae Japonicae. In tris-HCl buffer solution at pH 6.00, by employing cetyltrimethylammonium bromide, Cu2+ can quench the flThe present work is to find the optimum condition for fluorescence resonance energy transfer between CdTe QDs (donor) and rhodamine B (acceptor) and form a new method to detect copper in Flos Lonicerae Japonicae. In tris-HCl buffer solution at pH 6.00, by employing cetyltrimethylammonium bromide, Cu2+ can quench the fluorescence intensity of BRB and detect the concentration of Cu2+. Results show that a linear relationship could be established between the quenched fluorescence intensity of RhB and the concentration of Cu2+ in the range of 1.3×10-4～3.1×10-2 μg·mL-1, the limit of detection was 4.6×10-5 μg·mL-1 (r=0.996), RSD and the average recovery was 3.5% and 103.4% (n=5), respectively. It is concluded that the developed method was proved to be feasible to detect copper in Flos Lonicerae Japonicae..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 448 (2011)
Quantitative Determination of Trace Heavy Metals in Polluted Soil by Laser Induced Breakdown Spectroscopy
WU Wen-tao, MA Xiao-hong, ZHAO Hua-feng, ZHENG Ze-ke, ZHANG Min, and LIAO Yan-biao
Based on laser induced breakdown spectroscopy data analysis, a quantitative determination method of elements was introduced. This method takes the advantage of Fourier analysis to study different part of the spectrum-white noise, thermal radiation and emission spectral lines. Through band-pass filter, emission spectralBased on laser induced breakdown spectroscopy data analysis, a quantitative determination method of elements was introduced. This method takes the advantage of Fourier analysis to study different part of the spectrum-white noise, thermal radiation and emission spectral lines. Through band-pass filter, emission spectral lines and most noise were separated, only a little white noise was missed. By calculated similarity between detected line and its corresponding unit characteristic line, convolution intensity was introduced to measure the detected line intensity. With Cu 324.75 nm as the analysis line and Ti 337.28 nm as the base line, the way of separating spectrum mentioned before was carried out to detect trace Cu pollution in soil. Results contained two bright spots. First, The correlation coefficient between Cu concentration and the spectral intensity was up to 0.997 9. Last but not the least, the detectability of Cu in soil was 44 mg·kg-1, which is below the trace element thresholds for Class 2 soil used in the environmental quality standard for soil in China. At the same time, the relative error is always below 10%. Therefore the feasibility of this method for portable and instant detection of heavy metals in polluted soil was verified..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 452 (2011)
The Retrieval of Ozone Column Densities by Passive Differential Optical Absorption Spectroscopy during Summer at Zhongshan Station, Antarctic
LUO Yu-han, LIU Wen-qing, BIAN Lin-gen, LU Chang-gui, XIE Pin-hua, SI Fu-qi, and SUN Li-guang
Daily ozone column densities were monitored by Passive DOAS (differential optical absorption spectroscopy) from December 10th, 2008 to Feb 19th, 2009 at Zhongshan Station, Antarctic (69°22′24″ S， 76°22′14″ E). Considering the absorption of O3, OClO, NO2, O4, BrO and the Ring effect, ozone slant column densitiDaily ozone column densities were monitored by Passive DOAS (differential optical absorption spectroscopy) from December 10th, 2008 to Feb 19th, 2009 at Zhongshan Station, Antarctic (69°22′24″ S， 76°22′14″ E). Considering the absorption of O3, OClO, NO2, O4, BrO and the Ring effect, ozone slant column densities were retrieved using the zenith scattered sunlight as the light source. The results showed that there was no obvious “ozone hole” during the monitoring period, but ozone VCD (vertical column density) had greatly changed within short time scale, especially in middle December and early February. The analysis of passive DOAS and Brewer measurements of ozone VCD showed good agreement with the correlative coefficient of 0.863, while satellite board OMI measurements with the correlative coefficient of 0.840, which confirmed the validity of the monitoring of Passive DOAS..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 456 (2011)
Preparation and Spectral Characterisation of TiO2/Polyaniline Nanocomposites with 2D Lamellar Morphology
SHI Li, LUO Zhi-yuan, WU Xiao-dong, YANG Xu-jie, LU Lu-de, and WANG Xin
Nanostructured polyanilines (PANIs) are selected quite often as the matrix for the synthesis of inorganic/conductive polymer composites due to their excellent optical, electrical and magnetic properties. Herein both 2D lamellar PANI and the corresponding composite loading TiO2 species were successfully prepared from a Nanostructured polyanilines (PANIs) are selected quite often as the matrix for the synthesis of inorganic/conductive polymer composites due to their excellent optical, electrical and magnetic properties. Herein both 2D lamellar PANI and the corresponding composite loading TiO2 species were successfully prepared from a microemulsion system, as composed by dodecyl benzenesulfonic acid (DBSA) and water. The composite was achieved through a simultaneous polymerization of aniline in the presence of ammonium persulfate and hydrolysis of tetrabutyl titanate. Scanning electron microscopy (SEM) images indicate clearly that 2D PANI lamella are formed through organization of small PANI sheets. The inter-lamellar distance of PANI and that of TiO2/polyaniline composite, as derived from X-ray diffraction (XRD), is about 3.4 nm (nearly twice the length of one DBS molecule), suggesting that PANI and double-layered DBSA species are arranged in an alternated way. FTIR spectrum displays that PANI chains exhibit quinonoid and benzenoid strutures while both Raman and X-ray photoelectron spectroscopy (XPS) indicate that rutile TiO2 is produced upon hydrolyzation of tetrabutyl titanate in the microemulsion system. Moreover, UV-Vis spectrum suggests that the electronic absorption behaviour of PANI species is influenced upon loading TiO2..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 461 (2011)
Oil Atomic Spectrometric Feature Selection by Parzen Window Based Vague Sets Theory
XU Chao, ZHANG Pei-lin, REN Guo-quan, ZHANG Xiao-dong, and YANG Yu-dong
Large quantity and ambiguity of oil atomic spectrometric information greatly affects the applicable efficiency and accuracy in fault diagnosis. A novel method for choosing less and effective spectrometric features is presented. Based on gearbox test bed，we simulated the normal wear state and two typical faults to acquiLarge quantity and ambiguity of oil atomic spectrometric information greatly affects the applicable efficiency and accuracy in fault diagnosis. A novel method for choosing less and effective spectrometric features is presented. Based on gearbox test bed，we simulated the normal wear state and two typical faults to acquire the lubricant samples. The three wear states are regarded as three vague sets，and spectrometric feature values are vague values on vague sets. Based on similarity between vague values，mean vague sensibility(MVS) is defined to describe the sensitive degree of spectrometric feature to wear state. Besides，the membership degrees of vague sets greatly depend on human experience. The probability density distribution of spectrometric data of three wear states was estimated with Parzen window. Combined with Bayesian formula, the range of vague sets membership was calculated. Experimental results verify that the proposed method is of efficient help in choosing high fault-sensitive features from so many spectrometric features..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 465 (2011)
Application of Wavelet Transform on Iimproving Detecting Precision of the Non-Invasive Blood Components Measurement Based on Dynamic Spectrum Method
LI Gang, MEN Jian-long, SUN Zhao-min, WANG Hui-quan, LIN Ling, TONG Ying, and ZHANG Bao-ju
Time-varying noises in spectra collection process have influence on the prediction accuracy of quantitative calibration in the non-invasive blood components measurement which is based on dynamic spectrum (DS) method. By wavelet transform, we focused on the absorbance wave of fingertip transmission spectrum in pulse freTime-varying noises in spectra collection process have influence on the prediction accuracy of quantitative calibration in the non-invasive blood components measurement which is based on dynamic spectrum (DS) method. By wavelet transform, we focused on the absorbance wave of fingertip transmission spectrum in pulse frequency band. Then we increased the signal to noise ratio of DS data, and improved the detecting precision of quantitative calibration. After carrying out spectrum data continuous acquisition of the same subject for 10 times, we used wavelet transform de-noising to increase the average correlation coefficient of DS data from 0.979 6 to 0.990 3. BP neural network was used to establish the calibration model of subjects’ blood components concentration values against dynamic spectrum data of 110 volunteers. After wavelet transform de-noising, the correlation coefficient of prediction set increased from 0.677 4 to 0.846 8, and the average relative error was decreased from 15.8% to 5.3%. Experimental results showed that the introduction of wavelet transform can effectively remove the noise in DS data, improve the detecting precision, and accelerate the development of non-invasive blood components measurement based on DS method..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 469 (2011)
Fractal Characteristics of Visible Spectra Across a Hilly Area
ZHANG Fa-sheng, LIU Zuo-xin, WAN Hao-lei, and LIU Miao
The spectral characteristic of remotely sensed image is mainly the results of integrative effects on spectrum from heterogeneous ground reflectors. Investigating its spatial distribution characteristics may be helpful for image interpreting and modeling based on remote sensing technique. In the present study, spatial hThe spectral characteristic of remotely sensed image is mainly the results of integrative effects on spectrum from heterogeneous ground reflectors. Investigating its spatial distribution characteristics may be helpful for image interpreting and modeling based on remote sensing technique. In the present study, spatial heterogeneity of remotely sensed multispectral TM image across a hilly area in late October was studied by the combination of statistical method and multifractal analysis. The results showed that distribution of digital number (DN) values of visible spectra (0.45～0.69 μm) had statistical scale-invariance. The generalized fractal dimension function Dq suggested that distribution of TM 2 (0.52～0.60 μm) DN values was monofractal type, whereas DN values of TM 1 (0.45～0.52 μm) and TM 3 (0.63～0.69 μm) had multifractal distribution characteristics. The parameters (αmax-αmin) and ［f(αmax)-f(αmin)］ of multifractal spectra further indicated that TM 3 DN values had the highest spatial heterogeneity and most abundant information, followed by TM 1, while the extremely narrow spectrum of TM 2 DN values showed its relatively low spatial heterogeneity and information capacity..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 473 (2011)
Estimation of Leaf Area Index by Normalized Composite Vegetation Index Fusing the Spectral Feature of Canopy Water Content
CAO Shi, LIU Xiang-nan, LIU Mei-ling, CAO Shan, and YAO Shuai
The accurate inversion of leaf area index (LAI) in canopy is very important for guiding crop management and assessing crop yield. Sixty samples belonging to corn in four different areas of Jilin City were scanned by ASD field pro3 and LAI-2000 for optical data and LAI. A new vegetation index, the normalized composite VThe accurate inversion of leaf area index (LAI) in canopy is very important for guiding crop management and assessing crop yield. Sixty samples belonging to corn in four different areas of Jilin City were scanned by ASD field pro3 and LAI-2000 for optical data and LAI. A new vegetation index, the normalized composite Vegetation index (NCVI), containing the factor of canopy water content, is proposed in the present paper for a better quantitative estimation of LAI than with the remotely sensed normalized difference vegetation index (NDVI), especially in the arid and semi-arid areas. A model was built for inversion of LAI with NCVI, and experience validation. The results showed that there was a good linear correlation between the simulation LAI inversed from NCVI model and the real LAI values. The model breaking the limitations of the traditional empirical models for LAI inversion has a good result for estimating LAI of the dense canopy whose LAI value was greater than 3. In addition, NCVI model was very sensitive to the water environment of soil, and the inversion result in the arid and semi-arid areas was superior to the general area..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 478 (2011)
Accuracy Improvement of Spectral Classification of Crop Using Microwave Backscatter Data
JIA Kun, LI Qiang-zi, TIAN Yi-chen, WU Bing-fang, ZHANG Fei-fei, and MENG Ji-hua
In the present study, VV polarization microwave backscatter data used for improving accuracies of spectral classification of crop is investigated. Classification accuracy using different classifiers based on the fusion data of HJ satellite multi-spectral and Envisat ASAR VV backscatter data are compared. The results inIn the present study, VV polarization microwave backscatter data used for improving accuracies of spectral classification of crop is investigated. Classification accuracy using different classifiers based on the fusion data of HJ satellite multi-spectral and Envisat ASAR VV backscatter data are compared. The results indicate that fusion data can take full advantage of spectral information of HJ multi-spectral data and the structure sensitivity feature of ASAR VV polarization data. The fusion data enlarges the spectral difference among different classifications and improves crop classification accuracy. The classification accuracy using fusion data can be increased by 5 percent compared to the single HJ data. Furthermore, ASAR VV polarization data is sensitive to non-agrarian area of planted field, and VV polarization data joined classification can effectively distinguish the field border. VV polarization data associating with multi-spectral data used in crop classification enlarges the application of satellite data and has the potential of spread in the domain of agriculture..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 483 (2011)
Measurements of the Ignition Delay Times of n-Heptane by Using Characteristic Emission from OH Radical
XIE Wei, LI Ping, ZHANG Chang-hua, NIU Na, NIE Xiao-fei, and LI Cong-shan
Using a measurement system consisting of a monochromator, a photomultiplier tube (PMT), piezoelectric pressure sensors and a digital oscilloscope, the ignition delay times of n-heptane/O2 mixture were measured behind reflected shock waves in a chemical shock tube, the onset of ignition was indicated by the steepest risUsing a measurement system consisting of a monochromator, a photomultiplier tube (PMT), piezoelectric pressure sensors and a digital oscilloscope, the ignition delay times of n-heptane/O2 mixture were measured behind reflected shock waves in a chemical shock tube, the onset of ignition was indicated by the steepest rise of the characteristic emission from OH radical at 306.4 nm. The experimental conditions cover temperatures from 1 170 to 1 730 K, pressures at (1.0±0.1) and (0.75±0.05) atm, and equivalence ratio of 1.0. Under these experimental conditions, the correlation formulas of ignition delay time dependence on the temperature for n-heptane have been obtained. Present results indicate that the ignition delay times of n-heptane decreases exponentially with the increase in temperatures. While temperature increases, the change rate of ignition delay time of n-heptane under the pressure of 0.75 atm is less than that of 1.0 atm. Present ignition delay data are important for constructing the kinetic model of the combustion reaction and provide an experimental criterion for validating the combustion reaction mechanism of n-heptane..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 488 (2011)
A Spectral Wavelength Selection Algorithm Based on RMSECV Curve
ZHOU Yan, CAO Hui, and JU Lin-cang
The present paper presents a partial least squares (PLS) regression coefficient matrix based wavelength selection algorithm. The regression coefficient was used as the criterion for the wavelength selection, and the Root-Mean-Squares Error of Cross-Validation (RMSECV) curve was referred to, to decrease the primary numbThe present paper presents a partial least squares (PLS) regression coefficient matrix based wavelength selection algorithm. The regression coefficient was used as the criterion for the wavelength selection, and the Root-Mean-Squares Error of Cross-Validation (RMSECV) curve was referred to, to decrease the primary number of wavelength selected. Based on it, the uninformative wavelength can be eeleted through iteration steps, and the prediction accuracy of the model can also be improved. The algorithm was compared with the existing methods via a hydrogenation process Raman spectra data set, and the results indicated that the new algorithm can produce a more accurate and concise model than the existing ones..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 492 (2011)
New Method for Wave-Plate Orientation Determination Based on the Shape of the Modulated Spectrum
SONG Lian-ke, ZHU Hua-feng, HAN Pei-gao, MA Li-li, NIU Ming-sheng, KONG De-fu, YUN Mao-jin, and LI Dai-lin
A new method for the determination of fast axis of wave-plate is introduced. Based on the principle of electro-optic phase compensation in the wave-plate phase measuring method, the relation between the polarization extinction system out-put signal and the modulating signal can be acquired through the composition of frA new method for the determination of fast axis of wave-plate is introduced. Based on the principle of electro-optic phase compensation in the wave-plate phase measuring method, the relation between the polarization extinction system out-put signal and the modulating signal can be acquired through the composition of frequency fixed alternating voltage modulation signal. Through the analysis of this process with Jones matrix, the out-put signal was usually found to be the composition of fundamental frequency and second harmonic frequency, the composition signal reflects the axis information as well as the phase information of the wave-plate, and this phenomenon has never been noticed before. Through the analysis of this phenomenon, the transformation trends of the composed wave-form by rotating of wave-plates with different orientations were deduced, and through the observation of the transformation trend, one can easily distinguish the fast and slow axes of wave-plates with phase retardation >π as well as those with phase retardation <π, and their phenomena are reverse to each other..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 496 (2011)
Synthesis and Spectral Properties of a Novel Fluorinated Triphenylamine Derivative
XU Qing, XIONG Wei, WANG Qing-qi, and GAN Ning
A novel fluorinated triphenylamine derivative, N,N,N′,N′-tetraphenyl-［2′,2″,3′,3″,5′,5″,6′,6″-octafluoro-p-quaterphenyl］-4,4-diamine (OFTPA), was designed and synthesized via the palladium-catalyzed Suzuki coupling reaction of 4,4′-dibromooctafluorobiphenyl with triphenylamine-4-boronic acid (yield: 67％). Its moleculaA novel fluorinated triphenylamine derivative, N,N,N′,N′-tetraphenyl-［2′,2″,3′,3″,5′,5″,6′,6″-octafluoro-p-quaterphenyl］-4,4-diamine (OFTPA), was designed and synthesized via the palladium-catalyzed Suzuki coupling reaction of 4,4′-dibromooctafluorobiphenyl with triphenylamine-4-boronic acid (yield: 67％). Its molecular structure was characterized by elemental analysis, melting points, FTIR and 1H NMR spectroscopy, and the main FTIR absorption peaks and 1H NMR spectral bands of the compound were assigned. The energy level structure and photoluminescence properties of OFTPA were investigated by UV-Vis absorption, fluorescence spectroscopy and cyclic voltammetry (CV). The UV-Vis spectroscopy results show that the maximum absorption peak wavelength of OFTPA film is 355 nm, and its optical band gap (Eg) determined from the obtained absorption spectra is 3.09 eV. The fluorescence spectroscopy results show that OFTPA film can emit intense blue fluorescence with a peak wavelength of 448 nm and a full width at half maximum (FWHM) of 68 nm under UV excitation at 365 nm. So it is a promising candidate for blue electroluminescent materials. The CV results show that the highest occupied molecular orbital (HOMO) energy level and the lowest unoccupied molecular orbital (LUMO) energy level of OFTPA are -5.41 and -2.32 eV, respectively, indicating that it has good hole transport property. The results give a reference to further application to organic optoelectronic device of the target compound..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 500 (2011)
Molecular Structure and Luminescent Property of Bis(2-(4-Methyl-2-Hydroxyphenyl)benzothiazolate) Zinc
XU Hui-xia, CHEN Liu-qing, WANG Hua, HAO Yu-ying, and XU Bing-she
Bis(2-(4-methyl-2-hydroxyphenyl)benzothiazolate)zinc(Zn(4-MeBTZ)2) was synthesized. Its molecular structure was confirmed by single-crystal x-ray diffraction. Single-crystal data are as follows: space group triclinic, P-1; a=8.989 9(11) ， b=12.161 7(15) ， c=12.871 9(16) ， α=63.492(2)°， β=84.825(2) °， γ=71.Bis(2-(4-methyl-2-hydroxyphenyl)benzothiazolate)zinc(Zn(4-MeBTZ)2) was synthesized. Its molecular structure was confirmed by single-crystal x-ray diffraction. Single-crystal data are as follows: space group triclinic, P-1; a=8.989 9(11) ， b=12.161 7(15) ， c=12.871 9(16) ， α=63.492(2)°， β=84.825(2) °， γ=71.187(2)°. The steric hindrance provided by introduction methyl groups on phenoxide ring prohibited effectively the formation of pentacoordinate complex. There is distinct intermolecular π—π interaction between molecules. The dihedral angle between the phenol and benzothiazolate rings of Zn(4-MeBTZ)2 is 2.166 °. The HOMO energy, LUMO energy and optical gap are -5.84, -3.46 and 2.37 eV, respectively. The maximum wavelength peak of PL spectra located at 470 nm. The double-layer devices were employed using Zn(4-MeBTZ)2 as emitter and NPB as hole-transport material. The EL spectra split into two peaks located at 501 and 544 nm respectively. The broadened EL spectra were demonstrated to be originated from the exciplexes formed at the interface between NPB and Zn(4-MeBTZ)2..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 504 (2011)
Integration of Soft and Hard Classifications Using Linear Spectral Mixture Model and Support Vector Machines
HU Tan-gao, PAN Yao-zhong, ZHANG Jin-shui, LI Ling-ling, and LI Le
This paper presents a new soft and hard classification. By analyzing the target objects in the image distribution, and calculating the adaptive threshold automatically, the image is divided into three regions: pure regions, non-target objects regions and mixed regions. For pure regions and non-target objects regions, hThis paper presents a new soft and hard classification. By analyzing the target objects in the image distribution, and calculating the adaptive threshold automatically, the image is divided into three regions: pure regions, non-target objects regions and mixed regions. For pure regions and non-target objects regions, hard classification method (support vector machine) is used to quickly extract classified results; For mixed regions, soft classification method (selective endmember for linear spectral mixture model) is used to extract the abundance of target objects. Finally, it generates an integrated soft and hard classification map. In order to evaluate the accuracy of this new method, it is compared with SVM and LSMM using ALOS image. The RMSE value of new method is 0.203, and total accuracy is 95.48%. Both overall accuracies and RMSE show that integration of hard and soft classification has a higher accuracy than single hard or soft classification. Experimental results prove that the new method can effectively solve the problem of mixed pixels, and can obviously improve image classification accuracy..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 508 (2011)
Measurement of Chlorophyll Content and Distribution in Tea Plant’s Leaf Using Hyperspectral Imaging Technique
ZHAO Jie-wen, WANG Kai-liang, OUYANG Qin, and CHEN Quan-sheng
Chlorophyll content and distribution in plant’s leaves is an important index in estimation of plant nutrition information. In the present work, chlorophyll content and distribution in tea plant’s leaves were measured by hyperspectral imaging technique. First, hyperspectral image data were captured from tea plant’s leavChlorophyll content and distribution in plant’s leaves is an important index in estimation of plant nutrition information. In the present work, chlorophyll content and distribution in tea plant’s leaves were measured by hyperspectral imaging technique. First, hyperspectral image data were captured from tea plant’s leaves; then seven kinds of algorithms were used to extract the characteristic parameters from hyperspectral image; finally, seven fitted models were developed using the characteristics vectors and the reference measurements of chlorophyll contents respectively. Experimental results showed that the MSAVI2 model is superior to other models, and the results of the MSAVI2 model was achieved as follows: R=0.843 3 and RMSE=9.918 in the calibration set; R=0.832 3 and RMSE=8.601 in the prediction set. Finally, the chlorophyll content of each pixel in image was estimated by the fitted model, and the distribution of chlorophyll content in the tea plant’s leaf was described by pseudo-color map. This study sufficiently demonstrated that the chlorophyll content and distribution in tea leaf can be measured by hyperspectral imaging technique..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 512 (2011)
Retrieval and Validation of the Surface Reflectance Using HJ-1-CCD Data
LI Shen-shen, CHEN Liang-fu, TAO Jin-hua, HAN Dong, WANG Zhong-ting, and HE Bao-hua
The potentiality of the retrieval of surface reflectance using CCD camera aboard HJ-1A/B satellite was studied. It is very difficult to use dark targets in atmospheric correction due to the lack of near infrared band. The alternative normalized difference vegetation index (NDVI) and the red/blue reflectance ratio are dThe potentiality of the retrieval of surface reflectance using CCD camera aboard HJ-1A/B satellite was studied. It is very difficult to use dark targets in atmospheric correction due to the lack of near infrared band. The alternative normalized difference vegetation index (NDVI) and the red/blue reflectance ratio are detected from the spectral experiment in Beijing and the Pearl River Delta. Ground-based spectral data including grass, dense vegetation, water body, soil, residential roof and bright building etc. were used to validate the surface reflectance in Beijing, and the relative error in red, blue band is under 38.7% and 37.2% respectively. Uncertainties of the surface reflectance retrievals were analyzed. The comparison of MODIS surface reflectance product showed that there is a good agreement in the dense targets, and the correlation coefficient (R2) in red, blue band is as high as 0.809 4 and 0.723 9 respectively. HJ-1-CCD data can effectively reduce pixel-mixed impact on the cement roof and bright buildings, and the inversion accuracy is higher than MODIS products..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 516 (2011)
[in Chinese]
ZHANG Qian, XIONG Wei, CHEN Yu-qi, and LI Run-hua
A wood slice was used as absorber to transfer liquid sample to solid sample in order to solve the problems existing in directly analyzing aqueous solutions with laser-induced breakdown spectroscopy (LIBS). An optical-electrical dual pulse LIBS (OEDP-LIBS) technique was first used to enhance atomic emission of mercury iA wood slice was used as absorber to transfer liquid sample to solid sample in order to solve the problems existing in directly analyzing aqueous solutions with laser-induced breakdown spectroscopy (LIBS). An optical-electrical dual pulse LIBS (OEDP-LIBS) technique was first used to enhance atomic emission of mercury in laser-induced plasma. The calibration curves of mercury were obtained by typical single pulse LIBS and OEDP-LIBS techniques. The limit of detection (LOD) of mercury in these two techniques reaches 2.4 and 0.3 mg·L-1, respectively. Under current experimental conditions, the time-integrated atomic emission of mercury at 253.65 nm was enhanced 50 times and the LOD of mercury was improved by one order, if comparing OEDP-LIBS to single pulse LIBS. The required time for a whole analysis process is less than 5 minutes. As the atomic emission of mercury decays slowly while increasing the delay time between electrical pulse and laser pulse, increasing the electrical pulse width can further enhance the time integrated intensity of mercury emission and improve the detection sensitivity of mercury by OEDP-LIBS technique..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 521 (2011)
Preparation and Characterization of N, S, F—Codoped Nanosize TiO2 with Ionic Liquid
SUN Da-gui, DU Jun, LIU Zuo-hua, TAO Chang-yuan, and ZHAI Jun
N, S, F—co-doped TiO2 visible-light response photocatalyst(N—S—F—TiO2) was prepared with TiCl4, thiourea and ionic liquid (［C6mim］+［BF4］-) via the microwave-catalytic hydrolysis precipitation process followed by calcination in an NH3/N2 atmosphere. It was characterized by X-ray diffraction(XRD), X-ray photoelectron speN, S, F—co-doped TiO2 visible-light response photocatalyst(N—S—F—TiO2) was prepared with TiCl4, thiourea and ionic liquid (［C6mim］+［BF4］-) via the microwave-catalytic hydrolysis precipitation process followed by calcination in an NH3/N2 atmosphere. It was characterized by X-ray diffraction(XRD), X-ray photoelectron spectroscopy(XPS) and ultraviolet-visible diffusion reflectance spectroscopy(UV-Vis/DRS). Results showed that it was high purity anatase. The Ti—O—N, Ti—O—S and Ti—S bonds were formed in the TiO2 crystal and F used to dope TiO2 in the form of TiOF2. In the visible region 400~550 nm, it has strong absorption, and in 600~800 nm there was a strong absorption band. N—S—F—TiO2 prepared at volume ratio of ［C6mim］+［BF4］-/H2O of 5/95 exhibited the highest photocatalytic activity, and the degradation ratio of methyl orange was 95% under visible-light irradiation for 200 min. Multi-element co-doped synergistic effect was demonstrated by enhancement of the absorption in the visible region and higher visible light photocatalytic activity for N—S—F—TiO2..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 525 (2011)
Monitoring the Seasonal Distribution Pattern of Chlorophyll-a Concentration in Taihu Lake Based on CBERS-1 Imageries
ZHOU Lian-cheng, CHEN Jun, SUN Ji-hong, and FU Jun
Chlorophyll-a concentration is an important indicator for estimating the eutrophication degree of a lake. Taking advantage of the water qualities experimental data on 27 and 28 October, 2003, the paper constructs the chlorophyll-a concentration estimating model for Taihu Lake, China. And then, the study uses this chlorChlorophyll-a concentration is an important indicator for estimating the eutrophication degree of a lake. Taking advantage of the water qualities experimental data on 27 and 28 October, 2003, the paper constructs the chlorophyll-a concentration estimating model for Taihu Lake, China. And then, the study uses this chlorophyll-a concentration estimation model to estimate the seasonal distribution pattern of chlorophyll-a concentration from CBERS-1 imageries on 5 April, 28 April, 16 May, 5 August, and 30 October of 2006, and 5 July, 2007. According to the research results, it was found that the chlorophyll-a concentration is lower in summer and higher in autumn and winter, and could illuminate the four stages of phytoplankton growth in a year; Compared with the previous study reports, the chlorophyll-a concentration is higher than the actual concentration by estimating from the CBERS-1. There are still some problems for applying the CBERS-1 imageries to water qualities remote sensing, which should be improved by further study..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 530 (2011)
Monitoring Winter Wheat Population Dynamics Using an Active Crop Sensor
WU Jun-hua, YUE Shan-chao, HOU Peng, MENG Qing-feng, CUI Zhen-ling, LI Fei, and CHEN Xin-ping
Tiller density plays an important role in attaining optimum grain yield and applying topdressing N in winter wheat. However, the traditional approach based on determining tiller density is time-consuming and labor-intensive. As technology advances, remote sensing might provide an opportunity in eliminating this7 probleTiller density plays an important role in attaining optimum grain yield and applying topdressing N in winter wheat. However, the traditional approach based on determining tiller density is time-consuming and labor-intensive. As technology advances, remote sensing might provide an opportunity in eliminating this7 problem. In the present paper, an N rate experiment and a variety-seeding and sowing dates experiment were conducted in Quzhou County, Hebei Province in 2008/2009 to develop the models to predict the amount of winter wheat tillers. Positive linear relationships between vegetation indices and tillers were observed across growth stages (R2, 0.25～0.64 for NDVI; 0.26～0.65 for RVI). The validation results indicated that the prediction using NDVI had the higher coefficient of determination (R2, 0.54～0.64), the lower root mean square error (RMSE, 260～350 tillers m－2) and relative error (RE, 16.3%～23.0%) at early growth stages of winter wheat. We conclude that active GreenSeeker sensor is a promising tool for timely monitoring of winter wheat tiller density..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 535 (2011)
An Improved Method for Inversion of Particle Size Distribution from Scattering Spectrum
DAI Bing, YUAN Yin-nan, BAO Zhi-hua, and MEI De-qing
To reduce noise in the inversion for diffraction measurement of particle size distribution from scattering spectrum, an improved method was proposed. A regulate function was induced in the Chin-Shrine integral transform that led to the noise disappearing and didn’t affect the peak of inversion spectrum. The improved meTo reduce noise in the inversion for diffraction measurement of particle size distribution from scattering spectrum, an improved method was proposed. A regulate function was induced in the Chin-Shrine integral transform that led to the noise disappearing and didn’t affect the peak of inversion spectrum. The improved method was tested using linear CCD detector array. The result showed that the method largely improved previous results because of using the regulate function, and it is feasible and effective. The authors also explained that selecting the minimum and maximum of sampling angle by way of the different focal length reduced the different trouble of inversion spectrum. Using suitable focal length achieved good results in actual measurements..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 539 (2011)
Study on Selenium and Polysaccharide Distribution in Different Time Ginkgo Leaf
DENG Gui-chun, SUN Jing-yi, L Gai-fang, JU Zheng-nan, and YE Lin-lin
Selenium and selenium speciation in gingko leaf is different in different vegetal period. Each kind of dissolved selenium varies with the seasons. The total selenium content in gingko leaf picked in different season was studied and the various dissolved selenium content distribution was discussed. The selenium content Selenium and selenium speciation in gingko leaf is different in different vegetal period. Each kind of dissolved selenium varies with the seasons. The total selenium content in gingko leaf picked in different season was studied and the various dissolved selenium content distribution was discussed. The selenium content in July, September and after the first frost is respectively 1.875, 2.136 and 0.815 mg·kg-1. The selenium exists in gingko leaf primarily as a water-soluble speciation. According to the experiment, the thick polysaccharide content in the gingko leaf is in the order: July
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 543 (2011)
Study on the Content Determination of Total Flavonoids in Olea europaea L. Leaves
ZHENG Yuan-yuan, LI Chen, FENG Shi-lan, HUANG Xin-yi, LIU Yong-feng, CHEN Xiao-fen, and DI Duo-long
A quantitative determination method of the total flavonoids in Olea europaea L. leaves using rutin as a standard substance was developed. Two coloration systems including Al(NO3)3-NaNO2-NaOH and AlCl3 were both used. The latter was selected as the optimal determination method by comparing with the results. The main intA quantitative determination method of the total flavonoids in Olea europaea L. leaves using rutin as a standard substance was developed. Two coloration systems including Al(NO3)3-NaNO2-NaOH and AlCl3 were both used. The latter was selected as the optimal determination method by comparing with the results. The main interference of the matrix was discussed. The result showed that the AlCl3 coloration method is simple, accurate and reproducible with good linear relationship, and it can be looked as a reference method for the determination of total flavonoids in herbal materials or natural products..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 547 (2011)
Study of Ferric Species Distribution in Polymeric Phosphate Ferric Sulfate (PPFS)
ZHENG Huai-li, JIAO Shi-jun, HE Qiang, CHEN Rong, ZHANG Peng, and FANG Hui-li
Based on the strong polymeric role of phosphate (PO3-4) on the PFS, PO3-4 was introduced in the ferric sulfate (PFS), and a new type of composite flocculant polymeric phosphate ferric sulfate (PPFS) was developed. The study includes the preparation of PPFS，and erric species distribution in PFSS was investigated by ultrBased on the strong polymeric role of phosphate (PO3-4) on the PFS, PO3-4 was introduced in the ferric sulfate (PFS), and a new type of composite flocculant polymeric phosphate ferric sulfate (PPFS) was developed. The study includes the preparation of PPFS，and erric species distribution in PFSS was investigated by ultraviolet-visible spectrum method, infrared spectrum method and Fe-ferron complexation timed spectrophotometry method. The ultraviolet-visible spectrum showed that the change in the spectral curve of the different pH polymer ferric sulfate flocculants is corresponding to the flocculation morphology. Infrared spectra showed that the —P—O or PO vibration exists in the PPFS, certificated the ferric ion in PFS and phosphate caused the reaction, and produced the phosphate ferric polymer; and Fe-ferron complexation timed spectrophotometry showed that the amount of Fe(c) in polymeric phosphate ferric sulfate (PPFS) flocculants was the most in the three species, while the amount of Fe(a) and Fe(b) was small, that is PPFS mainly exists in the form of phosphate ferric polymer..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 551 (2011)
Analysis the Properties of Cr2O2-7 Adsorption onto Functional Organic Reagent Modified Nano-SiO2 by Flame Atomic Absorption Spectroscopy
ZHANG Zu-lei, and LI Lei
A new type of functional organic reagent modified nano-SiO2 sorbent (Si|(CH2)3-NH-CO-Ph-CH2-P(C6H5)3Br) was synthesized by several reasonable organic combination reactions using nano-SiO2, γ-Aminopropyl triethoxysilane (KH-550) and functional organic reagent (COOH-Ph-CH2-P(C6H5)3Br) as raw materials. The prepared new sA new type of functional organic reagent modified nano-SiO2 sorbent (Si|(CH2)3-NH-CO-Ph-CH2-P(C6H5)3Br) was synthesized by several reasonable organic combination reactions using nano-SiO2, γ-Aminopropyl triethoxysilane (KH-550) and functional organic reagent (COOH-Ph-CH2-P(C6H5)3Br) as raw materials. The prepared new sorbent was characterized by using FTIR, particle diameter and TG. A batch of adsorption experiments was performed to evaluate its adsorption behavior of Cr2O2-7 by flame atomic absorption spectroscopy (FAAS). The effects of solution pH, shaken time and sorbent amount on the extraction of Cr2O2-7 from aqueous solutions were studied. Results showed that when under the optimum conditions the solution pH 1, sorbent amount=0.1 g, and shaken time=30 min, the adsorption efficiency can be more than 95%. It indicated that this novel sorbent (Si｜(CH2)3-NH-CO-Ph-CH2-P (C6H5)3Br) was a solid sorbent being efficient and low-cost, with convenient separation, and can remove trace Cr2O2-7 in environmental waste water..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 555 (2011)
X-Ray Absorption Spectroscopic Evidence for the Formation of Pb(Ⅱ) Inner-Sphere Adsorption Complexes and Precipitates at the Alkaline Soil-Water Interface
HU Ning-jing, LUO Yong-ming, HUANG Peng, HU Tian-dou, XIE Ya-ning, WU Zi-yu, and SHI Xue-fa
Adsorption mechanisms of Pb on soil with high CaCO3 content were investigated by combined batch sorption and X-ray absorption fine structure (XAFS). Date from the batch equilibrium studies showed that Pb sorption was nonlinear and was well fitted to Langmiur isotherm. The XAFS data indicated that Pb could be adsorbed vAdsorption mechanisms of Pb on soil with high CaCO3 content were investigated by combined batch sorption and X-ray absorption fine structure (XAFS). Date from the batch equilibrium studies showed that Pb sorption was nonlinear and was well fitted to Langmiur isotherm. The XAFS data indicated that Pb could be adsorbed via the inner-sphere complex, the precipitation of calcium carbonate containing Pb (PbCaCO3), and outer-sphere Pb sorption complex. The formations of inner-sphere complexes and PbCaCO3 implied strong metal interactions with the surfaces the mechanistic reason for the affinity of Pb for CaCO3 as observed in macroscopic studies. At low metal concentration, 500 mg·L-1 of initial Pb, radial distance of the first-shell Pb—O (R1) was 0.169 2 nm, however, at 1 000 mg·L-1 of initial Pb, the R1 was 0.166 8 nm. These revealed that the percentage of inner-sphere complexes increased when the initial Pb was increased from 500 to 1 000 mg·L-1..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 560 (2011)
High Resolution Refractive Index Sensor Based on the Non-Complete Surface State of 1-D Photonic Crystal.
YAN Jiang-zhou, WU Yi-hui, XUAN Ming, and HAO Peng
A novel refractive index sensor based on one-dimensional photonic crystal non-complete surface defect is introduced and the principle and the method of the sensor are discussed. The experiment system used to detect the refractive index was constructed to get high resolution and high Q-value. The sensor is verified by dA novel refractive index sensor based on one-dimensional photonic crystal non-complete surface defect is introduced and the principle and the method of the sensor are discussed. The experiment system used to detect the refractive index was constructed to get high resolution and high Q-value. The sensor is verified by detecting the dimethyl sulphone solution. The experimental result indicates that this refractive index sensor’s sensitivity is 3 025 nm·RIU-1, and when the resolution of spectrometer is 0.01 nm the resolution of this sensor is 3.3×10-6 RIU. The Q value of this sensor is 260, and the sensor has good linearity in 1.4～1.42 range (the linearity is 0.991 27). It was analyzed how the photonic crystal periodicity and liquid thickness affect the Q value of the sensor. The result proved that this kind of total reflection photonic crystal surface wave sensor is label free, which is similar with SPR sensor, and the sensor has high resolution, high Q-value and has real-time survey characteristic..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 565 (2011)
Design of Non-Dispersed Infrared (NDIR) Methane Gas Sensor
ZHAO Zheng-jie, LIU Dong-xu, ZHANG Ji-long, WANG Zhi-bin, LI Xiao, and TIAN Er-ming
A Non-dispersed infrared (NDIR) methane gas sensors system based on infrared absorption spectrum theory was designed according to single light beam and double wavelengths technology. In the system, an infrared LED IRL715 serving as the light power, a absorptive gas cell with the function of dust-proof and damp-proof anA Non-dispersed infrared (NDIR) methane gas sensors system based on infrared absorption spectrum theory was designed according to single light beam and double wavelengths technology. In the system, an infrared LED IRL715 serving as the light power, a absorptive gas cell with the function of dust-proof and damp-proof and a pyroelectric detector LIM-262 are composed of optical probe. Signal condition uses active filter circuit and differential amplifier, and binomial expression fits the relation curve between methane concentration and voltage, which realizes accurate detection of gas concentration. Experiment approved that the sensor system with good consistency and applicability can detect the range of 5% methane reliably and have 0.5% of the sensitivity, possessing the conditions for industrial applications initially..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 08, 2021
- Vol. 31, Issue 2, 570 (2011)
Research Articles
Synthesis and Luminescent Properties of LuAG∶Ce3+ Transparent Ceramics by Solvo-Thermal Method
WANG Lin-xiang, ZHU Heng-jiang, WU Ling-yuan, DENG Kai-mo, GUO Chang-xin, and YIN Min
The precursor powders of LuAG∶Ce3+ transparent ceramics were synthesized by solvo-thermal method. The crystal structure and morphology of powders were analyzed by means of Fourier transform infrared spectroscopy, X-ray diffraction and scanning electron microscopy. The precursor powders were sintered into transparent ceThe precursor powders of LuAG∶Ce3+ transparent ceramics were synthesized by solvo-thermal method. The crystal structure and morphology of powders were analyzed by means of Fourier transform infrared spectroscopy, X-ray diffraction and scanning electron microscopy. The precursor powders were sintered into transparent ceramics in vacuum and then in nitrogen without any additive. The surface morphology of the transparent unpolished ceramics was characterized using scanning electron microscopy. Some factors that affect the transparency of ceramics were discussed. The UV-Vis fluorescence excitation and emission spectra of LuAG∶Ce3+ transparent ceramics were measured. The vacuum ultraviolet spectra of transparent ceramics were investigated using the synchrotron radiation as the excitation source. The excitation mechanism of Ce3+ was discussed at different excitation wavelength..
Spectroscopy and Spectral Analysis
- Publication Date: Oct. 20, 2021
- Vol. 31, Issue 2, 308 (2011)
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