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221.
毒性化学物质是指人为制造或在产品制造过程中衍生的化学有毒物质。学术机构的实验室对化学药品的使用具有少量多样的特点,由于实验的需要常会与这类物质接触,虽然接触的频率不及工业界高,但仍有相当高的危险性,因而应对实验室毒性物质严加管理,防止危害发生。  相似文献   
222.
Facing the rigorous safe situation of radioactive, biological and chemical weapon day by day, the safeguard of drinking water, which is the important resource that the survival and development of mankind depend on, will not only face the pollution of traditional pollutant, but also probably suffer the arriving pollution of the non-traditional pollutant in the future. Therefore, in order to improve the ability of drinking water safeguard to reply to the risk of arriving non-traditional pollution caused by suffering the terror or war, it is necessary to develop the removal technique of radioactive substances, biological and chemistry war agent. The category and harm of radioactive, biological and chemical substances which the drinking water may suffer are introduced firstly in the paper. Then the removal techniques of radioactive substances, biological and chemistry war agent are brought. On the basis of analyzing the removal techniques, the combination drinking water decontamination craft of pretreatment--membrane separate--handle behind is designed. Following the craft, the experiment of purging the radioactive substances simulation, biological and chemistry war agent is done. The experiment shows that the removal rates of ten kinds of radioactive nuclide can reach 99.9% and of biological war agent approach 100%. The quality of water which is polluted by chemistry war agent can reach some standard's require. Therefore, the fruit of research can provide the practical technique for drinking water safeguard in the future.  相似文献   
223.
范兆兴 《证据科学》2010,18(1):39-52
犯罪剖绘(criminal profiling)为分析(连续)犯罪行为型态的技术,藉由统计技术分析潜在犯罪者、被害者与犯罪现场迹证等三者之间相互联结可能性。然犯罪剖绘技术应用至"案件连结分析",可根据犯罪现场所遗留迹证(含心理迹证),预测/推论犯罪者之人口背景特征,并将这些案件之犯罪现场迹证系统化处理,建构成数据库,有助警察侦办连续型犯罪。经由案件连结分析所得证据,能否成为法庭上论罪之依据,在英美国家必须通过"Frye法则"与"Daubert测试法则"检验,即是否已经通过科学性检验,或同一学术领域同侪认可验证过程。因此,后续研究可朝更精确统计分析方法迈进,以提升案件连结分析数据库对于预测未发现犯罪者之准确率及其法庭证据力。  相似文献   
224.
At the Netherlands Forensic Institute, mRNA profiling for the purpose of organ tissue identification is frequently requested in casework. The previous version of the assay (denoted Organtyper) lacked markers for identifying adipose tissue, while this was occasionally questioned in casework. Here, three potential adipose markers are examined before incorporating one into the final Organtyper assay. The added value of the adipose marker becomes clear from looking at casework results.  相似文献   
225.
随着科技的发展,分析仪器在刑事技术领域的应用越来越广泛,有时往往会忽视对传统化学分析方法的应用。作为检验无机粉末的常用仪器,扫描电镜/能谱仪(SEM/EDS)和X射线衍射仪(XRD)受检出限的影响,无法准确分析样品中的低含量组分。本文在一起危险化学品放火案件检验中,为确定样品中含S元素的物质种类,利用化学分析法对其进行沉淀富集,再使用SEM/EDS和XRD检验,确认其中含有KMnO4和KHSO4,推测嫌疑人使用KMnO4和浓H2SO4等危险化学品实施放火,这在日常工作中比较罕见。通过总结相关工作经验,可为类似案事件的预防、物证提取和检验提供新的思路。  相似文献   
226.
In human identification, the victim's toothbrush is an invaluable personal item as the deposited cellular material contains DNA from which a reference profile can be produced. The profile obtained then allows direct comparison to be made with the profile from the unidentified body. This study was undertaken to determine the minimum number of bristle bundles that would generate a complete DNA profile. The minimum period of usage for a toothbrush to retain enough cells for genotyping was also investigated. We also tested two commonly used DNA extraction methods: QIAamp® DNA Mini Kit and Chelex® 100 to explore the efficiency of these protocols in recovering DNA from toothbrushes. In this experiment, volunteers brushed their teeth for 1, 7, 14, or 30 days. DNA was extracted from 5 and 10 bundles of bristles cut from the collected toothbrushes. The amount of DNA recovered was quantified by quantitative real-time PCR, and DNA genotyping was performed for each sample. Data revealed that QIAamp® DNA Mini Kit performed better at yielding DNA in terms of purity, quantity, and quality than Chelex® 100. It was also found that, with a suitable method of recovery, DNA samples from five bundles of bristles from all of the toothbrushes generated complete profiles. Based on the experimental results, a general guideline concerning the appropriate extraction method and the quantity of the starting material for the analysis of DNA from toothbrushes could be suggested.  相似文献   
227.
Several parameters can delay the first arrival of flies on a corpse and the subsequent development of the larvae. This study focuses on the development of Lucilia sericata (Diptera: Calliphoridae) (Meigen, 1826) on household chemical‐contaminated substrates. bleach, perfume, hydrochloric acid, caustic soda, insecticide, mosquito repellent, and gasoline in quantities consistent with an amount that could possibly be spilled on a corpse were mixed with beef liver to simulate contaminated fleshes. Larvae were bred at 25°C on these media until emergence. Four developmental parameters were followed: survival rates, development times, sex ratios, and adult sizes. Hydrochloric acid, insecticide, and gasoline killed all larvae. In low quantities, caustic soda and mosquito repellent increased the development time and decreased the adult size. However, high quantities of these chemicals killed all larvae. Lastly, bleach and perfume did not affect the survival rate and barely impacted the development time or adult size. These results demonstrate common household products spilled on a corpse can strongly affect the development of Calliphoridae larvae. The effects of such products should be considered in forensic entomology cases.  相似文献   
228.
目的探讨混合检材STR图谱分析结果。方法收集了3例实际案例检材,提取DNA,PCR扩增后用310型遗传分析仪检测。结果当DNA含量差距不大时,2人份混合检材检验结果易于分析,当DNA含量差距较大时或者2人份以上混合检材,图谱分析非常困难。结论根据本文提出的问题和实验结果,当遇到这样的混合样品,分析结论一定要谨慎。  相似文献   
229.
Has the EU's ozone policy been effective? In other words: What caused the 90 per cent phase-out of ozone depleting substances (ODS) within the EU? Was it due to an EU-wide regulatory approach, to national circumstances, or to the Montreal Protocol? As EU's environmental policy has not been overly successful so far, it would interesting to know why ozone policy is an area where the EU and its Member States have reached targets effectively over a relatively short time. We suggest that the effectiveness of EU's ozone policy is due to two factors that together secured this rapid phase-out. First, the ozone policy was enacted by means of an EU regulation – rather than by directives – which required all Member States and all larger ODS-generating corporations to implement a ban simultaneously. Second, with the US administration making a u-turn and the increased availability of ODS-substitute chemicals, Europe saw a political opportunity to speed up the phase-out process. A limited study of the phase-out of ODS in Spain supports this argument. While the EU's ozone policy has been effective, its success owes much to particular economic and political circumstances associated with the issue of ozone depletion.  相似文献   
230.
A key problem for counterterrorism is how large numbers of individuals can be screened most efficiently to discover terrorists. This question arises at security checkpoints of all kinds, from roadblocks to airline security counters. Some argue that certain categories of individuals, for instance, young Muslim men in the airline context, should be screened more heavily than others. Others deride this as racial profiling, and argue that any such scheme would be easily evaded. I examine a model of searching for terrorists among a population divided into categories that vary in their potential reliability or ease of recruitment as agents of terrorist attacks. The equilibria in the model feature profiling, in that different categories are searched with different intensities. Practical difficulties in implementing a rational profiling scheme are discussed.  相似文献   
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