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THE STUDIES ON THE SEPARATION AND IDENTIFICATION OF EPHEDRINES IN URINE BY GC/MSD
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作者 Jian Fang CUI Lin LI Tong Hui ZHOU(Institute of Materia Medica,Chinese Academy of Medical sciences,BeiJing 100050) 《Chinese Chemical Letters》 SCIE CAS CSCD 1990年第1期75-78,共4页
The separation and identification of the ephedrines(cathine,norephe-drine,ephedrine,pseudoephedrine,methylephedrine and ethylephedrine)and their derivatives obtained from TFAA,MSTFA,MSTFA+MBTFA and MSTFA+Ethyl acetate... The separation and identification of the ephedrines(cathine,norephe-drine,ephedrine,pseudoephedrine,methylephedrine and ethylephedrine)and their derivatives obtained from TFAA,MSTFA,MSTFA+MBTFA and MSTFA+Ethyl acetate deriva- tization were carried out by GC/MSD. 展开更多
关键词 THE STUDIES ON THE separation and identification OF EPHEDRINES IN URINE BY GC/MSD TFA TMS GC
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An efficient equivariant adaptive separation via independence algorithm for acoustical source separation and identification 被引量:2
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作者 CHENG Wei LU Jian Tao +1 位作者 GAO Lin ZHANG Jie 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2016年第12期1825-1836,共12页
To balance the convergence rate and steadystate error of blind source separation(BSS) algorithms, an efficient equivariant adaptive separation via independence(Efficient EASI) algorithm is proposed based on separating... To balance the convergence rate and steadystate error of blind source separation(BSS) algorithms, an efficient equivariant adaptive separation via independence(Efficient EASI) algorithm is proposed based on separating indicator, which was derived from the convergence condition of EASI, and can be used to evaluate the separation degree of separated signals. Furthermore, a nonlinear monotone increasing function between suitable step sizes and separating indicator is constructed to adaptively adjust step sizes, and forgetting factor is employed to weaken effects of data at the initial stage. Numerical case studies and experimental studies on a test bed with shell structures are provided to validate the efficiency improvement of the proposed method. This study can benefit for vibration & acoustic monitoring and control, and machinery condition monitoring and fault diagnosis. 展开更多
关键词 equivariant adaptive separation via independence adaptive step size separation indicator forgetting factor acoustical source separation and identification
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奶粉中脂肪酸的气相色谱-质谱分析 被引量:6
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作者 侯冬岩 回瑞华 +2 位作者 徐丽丽 刘晓媛 李学成 《分析测试学报》 CAS CSCD 北大核心 2007年第z1期231-232,235,共3页
To determine the fatty acids in milk powders,the fatty oils of milk powders were extracted by Rose-Gettlieb method,the fatty acids in the fatty oils were esterified by potassium hydroxide-methanol,and then analyzed by... To determine the fatty acids in milk powders,the fatty oils of milk powders were extracted by Rose-Gettlieb method,the fatty acids in the fatty oils were esterified by potassium hydroxide-methanol,and then analyzed by gas chromatography-mass spectrometry (GC-MS).The results indicate that main fatty acids’ carbon chain were from 8 to 24,each fatty acid has different conents in different samples and the content was determined by area normalization. 展开更多
关键词 Milk powders Fatty acid GC-MS separation and identification
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