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421.
422.
本文研究了人体组织中丁酮的顶空色谱测定方法。该方法以丙酮为内标,测得丁酮在肝、肾、血样品中的添加回收率大于75%。最小检出量为1ppm。经对一丁酮中毒死者解剖组织测定,丁酮的含量为肝0. 06mg/g,肾0. 23mg/g,血0. 47mg/ml。 相似文献
423.
D.G. Sanger I.J. Humphreys A.C. Patel M. Japp R.G.L. Osborne 《Forensic science international》1985,28(1):7-17
This paper describes a series of experiments designed to assess the evidential significance of gas chromatographic impurity patterns obtained from illicitly produced amphetamine. The experiments, based on the Leuckart route of amphetamine manufacture, were designed to investigate: the effect of reaction conditions on the production of known impurities, and the possibility that different chemists could produce amphetamine with identical impurity patterns by rigidly following the same synthetic procedure. The study provides strong support for the assumption that, if two illicit samples have the same impurity pattern, they have originated from the same batch. 相似文献
424.
目的检测尼美西痒阳性大鼠尿液中的代谢物。方法2只Wistar大鼠分别喂食半粒尼美西泮药丸,收集24h内尿液,用B葡萄糖醛酸酶水解,Oasis@HLB柱固相提取,以DB.35Ms柱为分离柱,气相色谱质谱联用法检测。结果从大鼠尿液中检出尼美西泮的4种代谢物:7-乙酰氨基尼美西泮、7-乙酰氨基硝基安定、7-氨基尼美西泮和2-氨基-5-硝基苯基苯甲酮及少量尼美西泮原体。结论尼美西泮在大鼠体内易代谢,在尿液中的主要代谢物为7-乙酰氨基尼美西泮和7-乙酰氨基硝基安定。 相似文献
425.
426.
目的测定不同死亡时间大鼠脑、肺、肝和骨骼肌电导率,研究不同组织器官EC与PMI的关系。方法 SD大鼠处死后,保存于25℃恒温条件下,于死后即刻(0d)、1d、2d、3d、4d、5d、6d和7d提取大鼠脑、肺、肝和骨骼肌,四种组织器官与去离子水按照一定比例制成浸渍液,测定各组织器官浸渍液EC值;分析其EC值与PMI的关系,建立与PMI关系的回归方程;比较大鼠死后四种组织器官EC变化规律,探讨不同组织器官腐败进程。结果死后1d内骨骼肌与脑组织EC无显著变化,2~7d快速增加;而肝、肺EC值在1d内已开始增加,且2~7d内均快速上涨。四种组织器官EC与PMI的关系用三次方程拟合较好,其中肝的相关系数最高,R~2=0.96,且四种组织器官的EC值在不同的PMI区段之间呈现出不同的增长规律。结论大鼠脑、肺、肝和骨骼肌EC与PMI相关性均较好,测定尸体组织器官EC有望成为法医实践中PMI推断的有效方法。 相似文献
427.
Characterization and Differentiation of Geometric Isomers of 3‐methylfentanyl Analogs by Gas Chromatography/Mass Spectrometry,Liquid Chromatography/Mass Spectrometry,and Nuclear Magnetic Resonance Spectroscopy 下载免费PDF全文
Tatsuyuki Kanamori Ph.D. Yuko T. Iwata Ph.D. Hiroki Segawa Ph.D. Tadashi Yamamuro Ph.D. Kenji Kuwayama Ph.D. Kenji Tsujikawa Ph.D. Hiroyuki Inoue Ph.D. 《Journal of forensic sciences》2017,62(6):1472-1478
The cis and trans isomers of 3‐methylfentanyl and its three analogs were chemically synthesized, and these compounds were characterized and differentiated by gas chromatography/mass spectrometry (GC/MS), liquid chromatography/mass spectrometry (LC/MS), and nuclear magnetic resonance (NMR) spectroscopy. The cis and trans isomers of the 3‐methylfentanyl analogs were completely separated by GC/MS. Although the high temperature of the GC injection port caused thermal degradation of β‐hydroxy‐3‐methylfentanyl, the degradation was completely suppressed by trimethylsilyl derivatization. The isomers were also well separated by LC/MS on an octadecylsilyl column with 10 mM ammonium acetate and methanol as the mobile phase. The proton NMR signals were split when the hydrochloride salts of the 3‐methylfentanyl analogs were dissolved in deuterated chloroform because stereoisomers were formed by the coordination of the hydrochloride proton to the nitrogen of the piperidine ring of the 3‐methylfentanyl analogs. 相似文献
428.
腐败血液中乙醇的顶空气相色谱分析 总被引:1,自引:0,他引:1
目的分析血液腐败后产生的乙醇及其他物质并探讨腐败血液中乙醇的检测及计算方法。方法以正常人空白血液制作腐败血样,采用1,4-二氧六环为内标物,通过顶空气相色谱进行定性及定量分析。结果血中乙醇在0.0625~1mg/mL范围内线性关系良好(r^2=0.9996),各质量浓度组的变异系数(CV%)〈2%,血中乙醇的最低检出限为1μg/mL(S/N≥3)。腐败血样所产生乙醇与正丙醇的比例大致为25:1。结论检验方法简便、准确。为法医毒化检验相关工作提供了依据。 相似文献
429.
Helen W. Kreuzer Ph.D. Jon H. Wahl Ph.D. Candace N. Metoyer Ph.D. Heather A. Colburn Ph.D. Karen L. Wahl Ph.D. 《Journal of forensic sciences》2010,55(4):908-914
Abstract: Samples containing the toxic castor bean protein ricin have been recently seized in connection with biocriminal activity. Analytical methods that enable investigators to determine how the samples were prepared and to match seized samples to potential source materials are needed. One commonly described crude ricin preparation method is acetone extraction of crushed castor beans. Here, we describe the use of solid‐phase microextraction and headspace analysis to determine whether castor beans were processed by acetone extraction. We prepared acetone‐extracted castor bean mash, along with controls of unextracted mash and mash extracted with nonacetone organic solvents. Samples of acetone‐extracted mash and unextracted mash were stored in closed containers for up to 109 days at both room temperature and ?20°C, and in open containers at room temperature for up to 94 days. Acetone‐extracted bean mash could consistently be statistically distinguished from controls, even after storage in open containers for 94 days. 相似文献
430.
Giorgia De Paoli Ph.D Samuel A. Lewis Sr. M.S. Ellyn L. Schuette M.S. Linda A. Lewis Ph.D. Raynella M. Connatser Ph.D. Tivadar Farkas Ph.D. 《Journal of forensic sciences》2010,55(4):962-969
Abstract: Photo‐ and thermal‐degradation studies on eccrine fingerprint components are presented herein. Dilute distinct solutions of urea, lactic acid, and seven amino acids were deposited on steel coupons and Teflon® disks, exposed to artificial sunlight or heat, extracted, and analyzed. This aim of this study was to determine whether the investigated eccrine components, previously determined to be Raman active for a parallel study, experienced photo‐ or thermally induced degradation, and if so, to determine the rate and identify any detectable products. Neither the amino acids nor urea exhibited photo‐degradation; however, when heated for a period of three minutes, the onset of thermal‐degradation was initiated at 100°C for the amino acids and 100°C for urea. Lactic acid, the major polymerization initiator of superglue fuming, showed photochemical and thermal‐degradation. These results could be used for future development of new latent fingerprint visualization methods, especially when lactic acid is degraded. 相似文献