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51.
用GC/ECD方法分析海洛因中毒尿液吗啡代谢物   总被引:2,自引:2,他引:0  
目的 考查尿检材中海洛因的代谢物吗啡和单乙酰吗啡的液液萃取条件、三氟乙酰化和气相色谱电子捕获检测 (GC/ECD)条件。方法 以烯丙吗啡为内标 ,氯仿∶异丙醇 (9∶1)为液相萃取剂萃取尿中的吗啡和单乙酰吗啡 ,采用MBTFA衍生化 (三氟乙酰化 ) ,GC/ECD检测。结果 尿中加样相对回收率吗啡 89% ,单乙酰吗啡 75 % ,最小检测量吗啡 5 0ng ,单乙酰吗啡 10 0ng。通过实验兔的中毒实验 ,对尿检材进行了分析。 结论 所建立的萃取与检测方法分析海洛因中毒尿检材中的吗啡准确、灵敏 ,可用于海洛因的吸毒检验  相似文献   
52.
目的 建立检测血液和尿液中头孢唑啉、头孢拉定、头孢哌酮和头孢噻肟的高效液相色谱法,并考察方法的适用性.方法 以乙酰苯胺为内标,血液和尿液用乙腈直接沉淀蛋白,采用Agilent Zorbax SB-Aq(250min×4.6mm,5 μm)色谱柱,流动相选用水(含0.12%三乙胺和0.12%乙酸)和乙腈的混合溶剂梯度洗脱,流速1 mL/min,检测波长254nm.结果 4种头孢菌素分离完全,工作曲线相关性均良好(r>0.9990),检出限为0.01μg/mL,回收率均不低于81.2%.结论 所建立的方法对血液和尿液中以上4种头孢菌素的检测快速、简便、准确,适用于实际检案中头孢菌素类药物的分析.  相似文献   
53.
目的:建立三七及其制剂三七片中人参皂苷Rg1的含量测定方法。方法:采用反相高效液相色谱法,色谱柱为Teknokroma Kromasil C18(5μm,2.1 cm×15 cm),以乙腈∶0.5 g/L磷酸水溶液(21∶79)为流动相,流速为0.3 ml/min,检测波长为203 nm,柱温为30℃。结果:人参皂苷Rg1浓度为21.4~534μg/ml时,线性关系良好(r=0.9991);平均回收率为99.3%,RSD=1.47%(n=6)。结论:本方法准确、快速、稳定、重现性好,可用于三七药材及其制剂的质量控制。  相似文献   
54.
Two major salvinorins, salvinorin A (SalA) and salvinorin B (SalB), in three Salvia divinorum dried leaf products and nine of its “concentrated extract” products circulated in Japan were determined. These ingredients were extracted twice with acetonitrile and decolored with graphite carbon powder. SalA and SalB were confirmed by liquid chromatography–tandem mass spectrometry in product ion scan mode, and quantified by high-performance liquid chromatography with UV detection (for SalA) and by mass spectrometry in single ion monitoring mode (for SalB). The SalA/SalB contents (μg/mg) were in the range of 3.2–5.0/0.10–0.17 in the dried leaf products and 4.1–38.9/0.26–2.42 in the “concentrated extract” products. These findings would be useful for analysis of S. divinorum-related products circulated in the drug market.  相似文献   
55.
Review of analytical techniques for arson residues   总被引:1,自引:0,他引:1  
Arson is a serious crime that affects society through cost, property damage, and loss of life. It is important that the methods and technologies applied by fire investigators in detection of evidence and subsequent analyses have a high degree of reliability, sensitivity, and be subject to rigorous quality control and assurance. There have been considerable advances in the field of arson investigation since the 1950s. Classification of ignitable liquids has been updated to include many new categories due to developments in the petroleum industry. Techniques such as steam or vacuum distillation and gas chromatography (GC) with flame ionization detection that may have been considered acceptable--even a benchmark--40 years ago, are nowadays generally disfavored, to the extent that their implementation may almost be considered as ignorance in the field. The advent of readily available mass spectrometric techniques has revolutionized the field of fire debris analysis, increasing the degree of sensitivity and discrimination possible considerably. Multi-dimensional GC--particularly GC x GC--while not yet widely applied, is rapidly gaining recognition as an important technique. This comprehensive review focuses on techniques and practices used in fire investigation, from scene investigation to analysis.  相似文献   
56.
液态爆炸物具有制造简易、不易识别、威力巨大、易于引爆等特点,这些特点增加了液态爆炸物安全检查的难度。液态爆炸物的安全检查分为探测、防护和处置三个环节。针对探测环节,文章综述了国内外主要使用的液态爆炸物探测技术及其特点,介绍了有代表性的技术产品,探讨了液态爆炸物探测技术的发展趋势,最后,对我国液态爆炸物安全检查行业的技术发展提出了几点建议。  相似文献   
57.
目的 采用超高效液相色谱法(ultra performance liquid chromatography,UPLC)建立绿萼梅药材的指纹图谱,为有效控制绿萼梅药材的质量奠定基础。方法 采用CORTECS C18色谱柱(2.1 mm×100 mm,1.6 μm),以乙腈(A)-0.1%甲酸水(B)溶液为流动相进行梯度洗脱,进样量为1 μL,流速为0.3 mL/min,检测波长260 nm。结果 通过相似度分析确定19个色谱峰构成绿萼梅药材指纹图谱的特征峰。结论 采用UPLC方法建立的指纹图谱具有精密度、稳定性、重复性良好的特点,可为绿萼梅化学成分的进一步提取分离和药效物质基础的研究提供科学依据。  相似文献   
58.
A method using liquid chromatography–tandem mass spectrometry (LC–MS/MS) to simultaneously quantify amphetamines, opiates, ketamine, cocaine, and metabolites in human hair is described. Hair samples (50 mg) were extracted with methanol utilizing cryogenic grinding. Calibration curves for all the analytes were established in the concentration range 0.05–10 ng/mg. The recoveries were above 72%, except for AMP at the limit of quantification (LOQ), which was 48%. The accuracies were within ±20% at the LOQ (0.05 ng/mg) and between −11% and 13.3% at 0.3 and 9.5 ng/mg, respectively. The intraday and interday precisions were within 19.6% and 19.8%, respectively. A proficiency test was applied to the validated method with z-scores within ±2, demonstrating the accuracy of the method for the determination of drugs of abuse in the hair of individuals suspected of abusing drugs. The hair concentration ranges, means, and medians are summarized for abused drugs in 158 authentic cases.  相似文献   
59.
The purpose of this research is to determine if latent fingerprints deposited on the exterior glass surfaces of vehicles, then covered in debris, can be recovered. Past research used liquid latex to lift soot to recover trace evidence. Recently, liquid latex has been used to recover latent fingerprints along the bottom of vehicles. In this study, a total of 216 latent fingerprints were deposited on the exterior windows of three vehicles. Three control and three experimental latent fingerprints were placed on each side window. The vehicles collected debris for either 2, 3, or 4 weeks. After debris collection, liquid latex was applied to the experimental sections. The underlying fingerprints were developed with white granular powder. Control fingerprints were developed directly with white granular powder. A chi-square test revealed a significant difference in fingerprint recovery between the control and liquid latex method (X2 = 9.026, d.f. = 1, p = 0.003). An odds ratio determined that the control method increases the probability of latent fingerprint recovery by 2.68. Fisher's exact test indicated that there is no statistically significant difference between the detail of the recovered control and experimental fingerprints (p = 0.065). This study demonstrates that recovery of fingerprints is possible using the liquid latex method; however, the control method recovers more fingerprints on the glass exterior of vehicles. If latent fingerprints are thought to be present on the exterior glass surfaces of vehicles, the control method should be used to improve vehicle processing by investigators.  相似文献   
60.
In Algeria, large quantities of hashish are seized every year. This study aimed to investigate the total content of major cannabinoids in the illicit seized hashish in Algeria over an 8-year period (2011–2018) in order to establish the chemical profile of North African hashish. A total of 3265 hashish samples were analyzed using a validated high-performance liquid chromatography–diode array detection (HPLC-DAD) method, allowing the simultaneous quantification of both the acidic and the neutral forms of Δ9-tetrahydrocannabinol (THC), cannabidiol (CBD), and cannabinol (CBN). The results revealed a slight upward trend in the mean THC content, from 7.0% in 2011 to 9.4% in 2018, with an overall mean value of 8.4%. The overall means of CBD and CBN content were 3.5% and 0.8%, respectively. The number of high-potency hashish samples gradually increased to reach 6% in 2018. Two distinct hashish chemotypes were identified: the highly populated chemotype II, corresponding to the traditional medium-potency hashish ([THC + CBN]/CBD ~ 2.16), and chemotype I, containing hashish samples of relatively high THC levels and low levels of CBD (ratio ~ 4.90). Both chemotypes I and II were characterized in the ternary plot, and the proportions (THC:CBD:CBN) were about 85%:13%:2% and 60%:35%:5%, respectively.  相似文献   
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