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排序方式: 共有349条查询结果,搜索用时 250 毫秒
21.
利用纳米粉体显现光滑客体汗潜指纹 总被引:3,自引:0,他引:3
纳米粉体材料色彩丰富,且对各种客体都有一定的吸附能力。这里介绍了应用吹显技术对14种纳米粉体材料在玻璃、瓷器、油漆等不同光滑客体表面遗留汗潜指纹的显现方法,实验证明显现效果较好。 相似文献
22.
F. Tagliaro W. F. Smyth S. Turrina Z. Deyl M. Marigo 《Forensic Science International Supplement Series》1995,70(1-3)
Capillary electrophoresis, the modern approach to instrumental electrophoresis, is probably the most rapidly expanding analytical technique that has appeared in recent years. In the hands of forensic toxicologists, capillary electrophoresis (CE) represents a powerful new analytical tool, which has proved suitable for the investigation of illicit drugs in seized preparations and also in complex biological matrices, among which is hair. CE can be applied according to different separation mechanisms, and among those that are toxicologically relevant are capillary zone electrophoresis and micellar electrokinetic capillary chromatography, which display different selectivities. For the investigation of hair for drugs of abuse, capillary electrophoresis proved effective, providing simultaneous determinations of different drugs without derivatization, with acceptable sensitivity (typically better than 1 ng of drug per mg of hair). The possibility of carrying out determinations of the same analytes, based on different separation mechanisms (capillary zone electrophoresis and micellar electrokinetic chromatography) with the same instrumentation, simply changing the buffer composition, provides an interesting possibility of ‘internal’ confirmation of the results. 相似文献
23.
目的建立测定血液中美西律(mexiletine)的液相色谱-串联质谱联用法(LC-MS/MS)。方法采用简便的乙腈蛋白沉淀法对血液进行预处理,应用Allure PFP Propyl液相柱分离,用电喷雾正离子模式离子化,多反应监测模式对美西律进行分析。结果美西律与内标纳洛酮分离良好,在0.02~10.00μg/mL内线性关系良好,相关系数为0.9999,回归方程为y=0.0283x-0.0151,日内与日间精密度的RSD均小于15%,最低检测限为0.01μg/mL。结论建立的LC-MS/MS方法简单、灵敏、可靠,可同时适用于美西律临床药物监测和法医毒物分析的需要。 相似文献
24.
目的 制备葛根素纳米冻干粉,并对其进行质量评价。方法 通过对冻干保护剂、冻干时间、预冻温度等的单因素考察,选择葛根素纳米冻干粉的最佳制备工艺,并对冻干粉的理化性质、纳米形态和质量进行评价。结果 葛根素纳米粉体的最佳成型工艺为:以甘露醇为冻干保护剂,置-80 ℃冰箱中预冻12 h,然后在-40 ℃、5 Pa下真空冷冻干燥36 h升华水分。制备的纳米粉体具有良好的溶解性能,平均粒径为108 nm,表面电位为-24.3 mV,平均含量约为140 mg/g。结论 采用冻干技术制备葛根素纳米粉体技术可行。 相似文献
25.
26.
杨黎华 《广西警官高等专科学校学报》2012,(1):28-30
吸毒驾车已成为一个巨大的交通安全隐患,具有较大的社会危害性。目前,中国对于吸毒驾车的管制存在法律不完备、主体不明确、检测吸毒困难等问题。有效管制吸毒驾车,可以借鉴国外的查处方法,同时要加快立法,建立制约机制、相关数据库和预警平台,适时集中进行专项整治,推广新型吸毒检测方法。 相似文献
27.
Schäffer M Gröger T Pütz M Dieckmann S Zimmermann R 《Journal of forensic sciences》2012,57(5):1181-1189
Abstract: The chemical profiling of illicit drugs is an important analytical tool to support the work of investigating and law enforcement authorities. In our work, comprehensive two‐dimensional gas chromatography–time‐of‐flight mass spectrometry (GC × GC‐TOFMS) combined with nontargeted, pixel‐based data analysis was adapted for the chemical profiling of 3,4‐methylenedioxymethamphetamine (MDMA). The validity and benefit of this approach was evaluated by analyzing a well‐investigated set of MDMA samples. Samples were prepared according to a harmonized extraction protocol to ensure the comparability of the chemical signatures. The nontargeted approach comprises preprocessing followed by analysis of variances as a fast filter algorithm for selection of a variable subset followed by partial least squares discriminant analysis for reduction to promising marker compounds for discrimination of the samples according to their chemical profile. Forty‐seven potential marker compounds were determined, covering most of the target impurities known from the harmonized one‐dimensional profiling as well as other compounds not previously elucidated. 相似文献
28.
近年来,苯丙胺类兴奋剂的β酮(bK)策划药相继在许多国家的毒品市场中出现,由于该类物质潜在的依赖性和已经导致的死亡事件,许多国家已经将其列为管制的物质。本文介绍了通过GC/MS和LC/MS方法对苯丙胺类兴奋剂的衍生物4-甲基甲卡西酮、bk-MDMA、bk-MBDB和bk-MDEA检测的相关研究结果,以说明其主要代谢途径。以期为临床医学、法庭毒理学以及禁毒机构监控该类物质提供参考。 相似文献
29.
This study takes the first step toward in situ analysis of powder drugs which does not require any alteration of the samples. A fast, inexpensive analytical method based on reflectance near-infrared (NIR) spectrometry and multivariate calibration was applied. A diode-array fiber-optic portable spectrometer in the 900-1700 nm range was employed. Samples were laboratory-prepared ternary powders (diacetylmorphine, caffeine, and paracetamol). Partial least squares regression was applied. The choice of the standard samples for calibration and validation was performed through a D-optimal experimental design. The explained variance was higher than 90%, and the relative root mean square errors were <2%. The number of principal components (6) was very low when compared with the number of raw variables (356 absorbance values). Response plots showed slopes and intercepts were very close to optimal values. Correlation coefficients ranged between 0.909 and 0.989. The method here proposed proved to be competitive with Fourier transform NIR spectrometry. 相似文献
30.
《Justice Quarterly》2012,29(4):517-537
Analyses of the impact on sentencing when alcohol and drug‐related mitigation is used in the sentencing phases of capital murder trials is virtually absent from the existing literature. The present study addresses this by exploring the effect of having mitigation with alcohol and drug themes accepted in a large sample (n = 804) of capital murder trials in North Carolina. Logistic regression analyses that include a number of relevant control variables reveal no substantive impacts of having alcohol mitigation accepted by capital murder juries, but drug mitigators that were either accepted or rejected by juries were associated with an increased risk of receiving a death sentence. Possible reasons for the results and their implications are discussed and suggestions are made for further study of the effects of alcohol/drug mitigation in capital trials. 相似文献