排序方式: 共有76条查询结果,搜索用时 15 毫秒
51.
陈凯旋 《南昌大学学报(理科版)》1988,12(4):1
为增进不锈钢性能,进行了不锈钢固体渗硼试验。结果表明;渗层表面形成了FeB、Fe_zB相。并随工艺变化可调整其相对含量。此渗层可以极大地提高耐磨性。但耐蚀性能降低。 相似文献
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ZHU Shuang-lai DOU Sheng-shan LIU Xin-ru LIU Run-hui ZHANG Wei-dong HUANG Hong-lin ZHANG Yi HU Yao-hua WANG Shu-ping . School of Pharmacy Second Military Medical University Shanghai P. R. China . School of Pharmacy Jiangxi University of Traditional Chinese Medicine Nanchang . School of Pharmacy Shanghai Jiaotong University Shanghai . School of Pharmacy Fujian University of Traditional Chinese Medicine Fuzhou P. ... 《高等学校化学研究》2011,27(1):38-44
A combined method of high performance liquid chromatograph-elecrtrospray-ionization mass spectrometer(HPLC-ESI-MS/MS) coupled with a photodiode array detector(HPLC-DAD) and principal component analysis(PCA) was applied to the qualitative and quantitative analyses of alkaloids in Cortex Phellodendri(CP) samples, and to the differentiation of two species of CP, Cortex Phellodendri Chinensis(CPC) and Cortex Phellodendri Amurensis(CPA). Twenty-two peaks appeared in the HPLC-MS base peak chromatogram of CP detec... 相似文献
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原子吸收光谱法测定12种中成药的10种无机元素 总被引:8,自引:0,他引:8
本文测定了12种中成药中10种无机元素,证明中成药含有丰富的无机元素,探讨了无机元素与中药的药效关系,结果表明中成药中的无机元素与药效有一定的关连。并且无机元素含量的多少也与药效有密切关系,为了保证中成药的药效,无机元素的含量多少也应该有合理的控制线,控制线的制订有待今后探讨。 相似文献
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黄新阳 《中国光学快报(英文版)》2010,(8):780-783
The spectroscopic characterization and fluorescence dynamics of Yb^3+:LiLa(WO4)2 crystal are investigated. The Yb^3+:LiLa(W04)2 crystal exhibits a broad absorption and emission spectral bands, large absorption and emission cross sections, and moderate fluorescence lifetime. Blue light emission around 480 nm is observed at 10 K and is demonstrated through cooperative upconversion from the deexcitation of excited Yb^3+-Yb^3+ pairs. 相似文献
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A hyperspectral imaging system is developed to detect dichlorvos residue on the surface of navel orange.After acquiring hyperspectral images of 400 navel oranges,the actual content of dichlorvos residue is measured by gas chromatography.Optimal wavelengths are extracted using the regression coefficients of partial least squares (PLS),and a PLS model with 12 factors is established.In the prediction set of 0.2282 11.652-mg/kg pesticide residue,the correlation coefficient and the root mean standard error are 0.8320 and 1.3416,respectively.The hyperspectral imaging technology can meet the requirement of online fast nondestructive detection. 相似文献
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Shou Ri SHENG* Xiao Ling LIU Wei ZHOU Xian HUANG Institutes of Chemistry Jiangxi Normal University Nanchang Department of Chemistry Zhejiang University 《中国化学快报》2005,(3)
Polymer-supported organic reagents have been applied to the rapid preparation of smallorganic molecules because they can provide attractive and practical methods forcombinatorial chemistry and solid-phase synthesis1. Vinylphosphonates bearing anelectron withdrawing groups at the α-position are versatile intermediates for the synthesisof some hetero- and carbocyclic compounds2. Many methods have been developed forpreparing their parent compounds, 1-alkenephosphonates. Among those methods, anim… 相似文献
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Simultaneous spectrophotometric determination of four preservatives in foodstuffs by multivariate calibration and artificial neural networks 总被引:1,自引:0,他引:1
Benzoic acid(BA),methylparaben(MP),propylparaben(PP)and sorbic acid(SA)are food preservatives,and they have well defined UV spectra.However,their spectra overlap seriously,and it is difficult to determine them individually from their mixtures without preseparation.In this paper,seven different chemometric approaches were applied to resolve the overlapping spectra and to determine these compounds simultaneously.With respect to the criteria of%relative prediction error(RPE)and%recovery, principal component... 相似文献
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Yiqing GAO Yitpin LIUNanchang .Institute of Aeronautical Technology Teaching Office of Physics Nanehang Jiangxi China 《Chinese Journal of Lasers》1992,1(1):83-88
This paper presents a new method to diagnose the welding arc temperaturefield on the basis of plasma physics,Talbot effect and Moire techniques.This method hasadvantages of immunity to mechanical shock and vibration,tunable sensitivity and conside-rable simple optical system. 相似文献