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International Journal of Agricultural and Biological Engineering 2017年第4期10卷 252-258页

作者： Chu Bingquan Lin Lei He Yong College of Biosystems Engineering and Food Science Zhejiang UniversityHangzhou Zhejiang 310058China

Histamine is a type of biogenic amine,which plays a major role in the health problems associated with seafood *** limits of histamine level in seafood have been set in many *** study focuses on investigating the feasibility and potentiality of determining histamine concentration in fish(Miichthys miiuy)by surface-enhanced Raman spectroscopy(SERS)combined with density functional theory(DFT).Both a gold colloid and a silver colloid were used to determine the enhancement effect for SERS detection of histamine standard solution,and the gold colloid exhibited more effective as compared to the silver *** protocol on extraction of histamine with 12%trichloroacetic acid and adjustment of pH with NaOH solution(5 mol/L)could significantly shorten sample preparation(20 min)and provide clear SERS spectra of *** peaks of histamine molecules were classified using the DFT and five spectra(953 cm^(-1),992 cm^(-1),1106 cm^(-1),1262 cm^(-1)and 1317 cm^(-1))were selected as the characteristic bands of histamine ***,the intensity of the peak at 1262 cm^(-1)had a good linear relationship with histamine concentration at 5-400 mg/kg with R^(2)=*** is concluded that the SERS-DFT approach will be a potential method for rapidly and reliably detecting histamine at levels from 5 mg/kg to 400 mg/kg in fresh fish.

关键词： surface-enhanced Raman spectroscopy(SERS) density functional theory(DFT) gold nanoparticles histamine rapid determination fish(Miichthys miiuy) food safety

rapid determination of Total Content of Five Major Anthraquinones in Rhei Radix et Rhizoma by NIR Spectroscopy

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Chinese Herbal Medicines 2017年第3期9卷 250-257页

作者： Hao Zhan Jing Fang Hong-wei Wu Hong-jun Yang Hua Li Zhu-ju Wang Bin Yang Li-ying Tang Mei-hong Fu Institute of Chinese Materia Medica China Academy of Chinese Medical Sciences

Objective To establish a new method with near-infrared（NIR） spectroscopy to determine the total content of emodin, chrysophanol, rhein, aloeemodin, and physcion. NIR was used in this study to provide rapid and nondestructive analysis results. Methods In the first place, HPLC was used to measure the total content of emodin, chrysophanol, rhein, aloe-emodin and physcion in Rhei Radix et Rhizoma（RR） as a reference. In the second place, the spectral regions, regression methods, pretreatment methods, and partial least squares（PLS） factors were compared to increase the feasibility of the model. In the last, the root mean square error of calibration（RMSEC）, root mean square error of cross validation（RMSECV）, root mean square error of prediction（RMSEP）, and correlation coefficient（r） were used as assessment parameters. Results PLS with first derivative pretreatment in the ranges of 4242-5581 cm^（-1）, 5885-6233 cm^（-1） and 6394-7011 cm^（-1） provided the best results. The RMSEC and RMSEP obtained were 0.134 and 0.226 respectively. The according determination coefficients of the quantitative model were 0.99 and 0.94. Conclusion NIR spectroscopy as a quick and nondestructive analytical method may be used to determine the total content of emodin, chrysophanol, rhein, aloeemodin, and physcion for the quality control of RR.

关键词： near-infrared spectroscopy partial least squares quality control rapid determination Rhei Radix et Rhizoma

rapid determination of Pesticide Residues in Fresh Sweet Corn

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Agricultural Science & Technology 2014年第10期15卷 1696-1698,1702页

作者：林玉婵冯会胜陈孟君黄子敬惠州市农产品质量安全监督检测中心广东惠州516008

Objective] This study aimed to detect al organophosphate, organochlorine and pyrethroid pesticide residues in fresh sweet corn in one determination using a gas chromatograph. [Method] The pesticide residues in fresh sweet corn were ex-tracted and loaded to simultaneously the gas chromatograph Agilent 6890N which was equipped with two autosamplers, two columns and two detectors. [Result] Al the 26 pesticides were completely separated and eluted out within 25 min. The re-coveries of standard addition of the 26 pesticides ranged from 76% to 106%, with relative standard deviations （RSD） ranging from 0.5% to 8.9%. The linear regression equation fit wel from 0.050 to 1.500 mg/L corn extract （r2＆gt;0.996）. [Conclusion] The method is accuracy, which meets the requirements of pesticide residue analysis and can be used for the rapid detection, qualitative and quantitative analysis of pesticide residues in fresh sweet corn.

关键词： Fresh sweet corn Pesticide Multiple residue rapid determination Gas chromatography

rapid satellite-to-site visibility determination based on self-adaptive interpolation technique

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Science China(Technological Sciences) 2017年第2期60卷 264-270页

作者： HAN Chao GAO XiaoJie SUN XiuCong School of Astronautics Beihang University Beijing 100191 China

rapid satellite-to-site visibility determination is of great significance to coverage analysis of satellite constellations as well as onboard mission planning of autonomous spacecraft. This paper presents a novel self-adaptive Hermite interpolation technique for rapid satellite-to-site visibility determination. Piecewise cubic curves are utilized to approximate the waveform of the visibility function versus time. The fourth-order derivative is used to control the approximation error and to optimize the time step for interpolation. The rise and set times are analytically obtained from the roots of cubic polynomials. To further increase the computational speed, an interval shrinking strategy is adopted via investigating the geometric relationship between the ground viewing cone and the orbit trajectory. Simulation results show a 98% decrease in computation time over the brute force method. The method is suitable for all orbital types and analytical orbit propagators.

关键词： satellite-to-site visibility rapid determination self-adaptive Hermite interpolation viewing cone

Stability of selenium and its speciation analysis in water using automatic system separation and HR-ICP-MS measurement

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Chinese Chemical Letters 2022年第7期33卷 3444-3450页

作者： Junqiang Yang Yawen Chen Keliang Shi Kesheng Hu Run Li Xiaoqing Gao Qian Wang Weibo Zhang Yun Zhou Yanyun Wang Jiangang He Tonghuan Liu Xiaolin Hou Frontier Science Center for Rare Isotopes Lanzhou UniversityLanzhou 730000China School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China Beijing National Laboratory for Molecular Sciences Fundamental Science Laboratory on Radiochemistry&Radiation ChemistryCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China Key Laboratory of Special Function Materials and Structure Design Ministry of EducationLanzhou UniversityLanzhou 730000China CNNC Lanzhou Uranium Enrichment Co. Ltd.Lanzhou 730000China Environmental Monitor Center of Gansu Province Lanzhou 730000China

A simple and convenient method has been developed for the pre-concentration and separation of inorganic selenium species from environmental water samples using anion exchange chromatographic column combined with high resolution inductively coupled plasma mass spectrometry(HR-ICP-MS)measurement.^(75)Se(Ⅳ) and ^(75)Se(Ⅵ)were prepared and used as tracers during the *** volatility of selenium during solution evaporation was investigated to establish a reliable water samples pretreatment *** parameters which affect the uptake of Se(Ⅳ)and Se(Ⅵ)on Dowex1×8 resin was optimized and the procedure for Se(Ⅳ)and Se(Ⅵ)separation was *** Se(Ⅳ)and Se(Ⅵ)are retained on the column in natural or alkaline solution with high distribution *** successive gradient elution of pre-concentrated species of selenium with HNO_(3)solution allows to differentiate between ***(Ⅳ)and Se(Ⅵ)finally were eluted with 0.05 mol/L HNO_(3) and 5.0 mol/L HNO_(3),*** proposed method has been successfully verified using the certified reference materials(CRMs)of real water samples,and spiked recoveries for real samples were 98%-104%with 5%relative standard deviations(RSDs).The developed procedure is proved to be reliable and can be used for the rapid determination of selenium species in environmental water samples.

关键词： Inorganic selenium Speciation Automatic system separation rapid determination Water sample

Near-infrared spectroscopy method for rapid proximate quantitative analysis of nutrient composition in Pacific oyster Crassostrea gigas

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Journal of Oceanology and Limnology 2023年第1期41卷 342-351页

作者： Zhe LI Haigang QI Ying YU Cong LIU Rihao CONG Li LI Guofan ZHANG CAS and Shandong Province Key Laboratory of Experimental Marine Biology Center for Ocean Mega-ScienceInstitute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Biology and Biotechnology Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China Laboratory for Marine Fisheries Science and Food Production Processes Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266237China Public Technical Service Center Institute of OceanologyChinese Academy of SciencesQingdao 266071China National&Local Joint Engineering Key Laboratory of Ecological Mariculture Institute of OceanologyChinese Academy of SciencesQingdao 266071China University of Chinese Academy of Sciences Beijing 100049China

Glycogen,amino acids,fatty acids,and other nutrient components affect the flavor and nutritional quality of *** based on near-infrared reflectance spectroscopy(NIRS)were developed to rapidly and proximately determine the nutrient content of the Pacific oyster *** of *** from 19 costal sites were freeze-dried,ground,and scanned for spectral data collection using a Fourier transform NIR spectrometer(Thermo Fisher Scientific).NIRS models of glycogen and other nutrients were established using partial least squares,multiplication scattering correction first-order derivation,and Norris *** R_(C) values of the glycogen,fatty acids,amino acids,and taurine NIRS models were 0.9678,0.9312,0.9132,and 0.8928,respectively,and the residual prediction deviation(RPD)values of these components were 3.15,2.16,3.11,and 1.59,respectively,indicating a high correlation between the predicted and observed values,and that the models can be used in *** models were used to evaluate the nutrient compositions of 1278 oyster *** content was found to be positively correlated with fatty acids and negatively correlated with amino *** glycogen,amino acid,and taurine levels of *** cultured in the subtidal and intertidal zones were also significantly *** study suggests that *** NIRS models can be a cost-effective alternative to traditional methods for the rapid and proximate analysis of various slaughter traits and may also contribute to future genetic and breeding-related studies in Pacific oysters.

关键词： Pacific oyster Crassostrea gigas near-infrared reflectance spectroscopy(NIRS) nutrient composition rapid determination