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Low-Frequency Vibrations of Indole Derivatives by Terahertz Time-Domain Spectroscopy

Journal of Electronic Science and Technology 2016年第4期14卷 329-336页

作者： Ya-Ru Dang Shao-Ping Li Hui Liu Shao-Xian Li Jian-Bing Zhang Hong-Wei Zhao School of Chemical Engineering East China University of Science and TechnologyShanghai200237China School of Precision Instrument and Optoelectronics Engineering Tianjin UniversityTianjin 300072China Key Laboratory of Interfacial Physics and Technology Shanghai Institute of Applied PhysicsChinese Academy of SciencesShanghai 201800China

Several indole derivatives with different ＇3-＇ substituents have been investigated by terahertz （THz） time-domain spectroscopy. The low-frequency absorption spectra and refractive indices were obtained in the range of 0.2 THz to 2.5 THz （7 cm-1 to 83 cm-1）. These derivatives with different substituents present distinct features, which suggests that THz spectroscopy is sensitive to different structures and components of these chemicals. The density functional theory was employed to calculate the low-frequency vibrational properties of indole-3-carboxylic acid and indole-3-propionic acid based on their crystal structures, and the intermolecular interactions were involved. Meanwhile, the temperature dependence of the spectra agreed with the calculated results. The quantitative analysis of a ternary mixture was studied by taking the THz fingerprints into account, and the results demonstrate THz spectroscopy has great potential for the practical applications in biochemistry and pharmaceutics.

关键词： characteristic spectrum density functional theory indole derivatives low-frequency vibration terahertz.

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Oil spill detection by a support vector machine based on polarization decomposition characteristics

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Acta Oceanologica Sinica 2016年第9期35卷 86-90页

作者： ZOU Yarong SHI Lijian ZHANG Shengli LIANG Chao ZENG Tao National Satellite Ocean Application Service State Oceanic Adminstration Key Laboratory for Space Ocean Remote Sensing and Application State Oceanic Administration School of English Language Literature and CultureBeijing International Studies University

Marine oil spills have caused major threats to marine environment over the past few *** early detection of the oil spill is of great significance for the prevention and control of marine *** present,remote sensing is one of the major approaches for monitoring the oil *** polarization synthetic aperture radarc SAR data are employed to extract polarization decomposition parameters including entropy（H） and reflection entropy（A）.The characteristic spectrum of the entropy and reflection entropy combination has analyzed and the polarization characteristic spectrum of the oil spill has developed to support remote sensing of the oil *** findings show that the information extracted from（1-A）×（1-H） and（1-H）×A parameters is relatively evident *** results of extraction of the oil spill information based on H×A parameter are relatively not *** combination of the two has something to do with H and A *** general,when H〉0.7,A value is relatively ***,the extraction of the oil spill information using（1-A）×（1-H） and（1-H）×A parameters obtains evident *** combined parameter is adopted,oil well data would cause certain false alarm to the extraction of the oil spill *** particular the false alarm of the extracted oil spill information based on（1-A）×（1-H） is relatively high,while the false alarm based on（1-A）×H and（1-H）×A parameters is relatively small,but an image noise is relatively *** oil spill detection employing polarization characteristic spectrum support vector machine can effectively identify the oil spill information with more accuracy than that of the detection method based on single polarization feature.

关键词： oil spill polarization synthetic aperture radar characteristic spectrum entropy reflection entropy support vector machine

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Study of the best decocting time of sun dried ginseng by using the hyperspectral imaging technology

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Journal of Innovative Optical Health Sciences 2016年第6期9卷 21-25页

作者： Qing He Lan Liang Zhenqiang Chen Qichang Pang Jing Zhao Key Laboratory of Optoelectronic Information and Sensing Technologies of Guangdong Higher Educational Institutes Jinan University Guangzhou 510630P.R.China Department of Biomedical Engineering Guangdong Medical College Dongguan 523808 P.R.China College of Science South China Agricultural University Guangzhou 510640P.R.China

In this research,a new method based on the hyperspectral imaging for searching the best decocting time of sun dried ginseng is *** spectral images at diferent decocting time of test sample have been taken by the st aring hyperspectral fAuorescence imaging systen and the solubility of active ingredients have been discussed by analyzing the changes on the *** spectr al range of the system is 400-720nm and the spectral resolution is *** the decocting process,the active ingredients of nonsoaked ginseng was dissolved in the tissue fluid at first,and reached equilibrium condition at last after the precipitation-dissolution reciprocating process of *** last,the experiment al results show that the best decoction time of sun dried ginseng is about 60 min after boiling.

关键词： Sun dried ginseng active ingredients decocting time hyperspectral imaging characteristic spectrum characteristic peaks

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Detecting Model of Soil Total Nitrogen Content Based on NIR Technology and Wavelet Packet Analysis

Detecting Model of Soil Total Nitrogen Content Based on NIR ...

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亚洲精细农业与计算机农业应用联合大会

作者： ZHENG Lihua LI Minzan AN Xiaofei PAN Luan SUN Hong Key Laboratory of Modern Precision Agriculture System Integration Research China Agricultural University Ministry of Education Beijing 100083 China.

It is the actual demand of agricultural production to develop the portable soil total nitrogen （TN） detector with higher accuracy. In order to meet the detecting accuracy demand of the portable TN detector based multi-band near-infrared reflectivity （NIR） technology, the NIR model detecting TN was developed based on wavelet packet analysis. In order to establish the TN detecting model with a finite number of near-infrared bands, 100 soil samples were collected for calibration and validation from the field. First, using the high-precision NIR detecting instrument to scan the target and obtaining the continuous spectra of soil samples in the laboratory. Secondly, using the method of wavelet packet analysis, the original signal of each soil sample was decomposed and reconstructed. Then the characteristic spectrum corresponding to each soil parameter was drawn form the original signal, and the partial least square （PLS） model for TN was established based on the drawn characteristic spectrum, which includes 24-band spectrum as the independent variables. Finally, due to the spectral feature of the characteristic spectrum of TN, nine near-infrared bands were selected and identified as the independent variables of the portable TN detecting instrument in accordance with the characteristics of each band’s contribution to the extent of the model. The TN content detecting model was established in the laboratory, and the determined R2 reached 0.700. It was showed that the accuracy of the TN detecting model was able to meet the needs of actual production. The research concluded that wavelet packet analysis could eliminate or substantially reduce the factors outside the parameters to the spectrum directly or indirectly, and the obstacles in establishing linear models for soil parameters were removed. It is feasible and potential to the real-time prediction of TN content.

关键词： Precision agriculture soil total nitrogen wavelet packet characteristic spectrum portable TN detector NIR

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