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51.
Using Cluster Analysis and ICP‐MS to Identify Groups of Ecstasy Tablets in Sao Paulo State,Brazil 下载免费PDF全文
Camila Maione M.Sc. Vanessa Cristina de Oliveira Souza M.Sc. Loraine Rezende Togni M.Sc. José Luiz da Costa Ph.D. Andres Dobal Campiglia Ph.D. Fernando Barbosa Ph.D. Jr. Rommel Melgaço Barbosa Ph.D. 《Journal of forensic sciences》2017,62(6):1479-1486
The variations found in the elemental composition in ecstasy samples result in spectral profiles with useful information for data analysis, and cluster analysis of these profiles can help uncover different categories of the drug. We provide a cluster analysis of ecstasy tablets based on their elemental composition. Twenty‐five elements were determined by ICP‐MS in tablets apprehended by Sao Paulo's State Police, Brazil. We employ the K‐means clustering algorithm along with C4.5 decision tree to help us interpret the clustering results. We found a better number of two clusters within the data, which can refer to the approximated number of sources of the drug which supply the cities of seizures. The C4.5 model was capable of differentiating the ecstasy samples from the two clusters with high prediction accuracy using the leave‐one‐out cross‐validation. The model used only Nd, Ni, and Pb concentration values in the classification of the samples. 相似文献
52.
Adamczyk Marcin M.Sc. Eng Sieniło Maciej Ph.D. Sitnik Robert Ph.D. Woźniak Adam Ph.D. 《Journal of forensic sciences》2017,62(4):889-899
We present a new generation of three‐dimensional (3D) measuring systems, developed for the process of crime scene documentation. This measuring system facilitates the preparation of more insightful, complete, and objective documentation for crime scenes. Our system reflects the actual requirements for hierarchical documentation, and it consists of three independent 3D scanners: a laser scanner for overall measurements, a situational structured light scanner for more minute measurements, and a detailed structured light scanner for the most detailed parts of tscene. Each scanner has its own spatial resolution, of 2.0, 0.3, and 0.05 mm, respectively. The results of interviews we have conducted with technicians indicate that our developed 3D measuring system has significant potential to become a useful tool for forensic technicians. To ensure the maximum compatibility of our measuring system with the standards that regulate the documentation process, we have also performed a metrological validation and designated the maximum permissible length measurement error EMPE for each structured light scanner. In this study, we present additional results regarding documentation processes conducted during crime scene inspections and a training session. 相似文献
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54.
Teixeira H Verstraete A Proença P Corte-Real F Monsanto P Vieira DN 《Forensic science international》2007,170(2-3):148-155
A fully validated, sensitive and specific method for the extraction and quantification of Delta(9)-tetrahydrocannabinol (THC) and 11-nor-9-carboxy-Delta(9)-THC (THC-COOH) and for the detection of 11-hydroxy-Delta(9)-THC (11-OH THC) in oral fluid, urine and whole blood is presented. Solid-phase extraction and liquid chromatography-mass spectrometry (LC-MS) technique were used, with electrospray ionization. Three ions were monitored for THC and THC-COOH and two for 11-OH THC. The compounds were quantified by selected ion recording of m/z 315.31, 329.18 and 343.16 for THC, 11-OH THC and THC-COOH, respectively, and m/z 318.27 and 346.26 for the deuterated internal standards, THC-d(3) and THC-COOH-d(3), respectively. The method proved to be precise for THC and THC-COOH both in terms of intra-day and inter-day analysis, with intra-day coefficients of variation (CV) less than 6.3, 6.6 and 6.5% for THC in saliva, urine and blood, respectively, and 6.8 and 7.7% for THC-COOH in urine and blood, respectively. Day-to-day CVs were less than 3.5, 4.9 and 11.3% for THC in saliva, urine and blood, respectively, and 6.2 and 6.4% for THC-COOH in urine and blood, respectively. Limits of detection (LOD) were 2 ng/mL for THC in oral fluid and 0.5 ng/mL for THC and THC-COOH and 20 ng/mL for 11-OH THC, in urine and blood. Calibration curves showed a linear relationship for THC and THC-COOH in all samples (r(2)>0.999) within the range investigated. The procedure presented here has high specificity, selectivity and sensitivity. It can be regarded as an alternative method to GC-MS for the confirmation of positive immunoassay test results, and can be used as a suitable analytical tool for the quantification of THC and THC-COOH in oral fluid, urine and/or blood samples. 相似文献
55.
Brandão RB Martin CC Catirse AB de Castro E Silva M Evison MP Guimarães MA 《Journal of forensic sciences》2007,52(4):913-919
The objective was to investigate color change and surface damage in dental resin composites exposed to high temperatures over different time intervals for comparative purposes. Samples were prepared using two resins - Z100(R) (R1) and Charisma (R2), heated at the following temperatures: 200 degrees C, 400 degrees C, 600 degrees C, 1000 degrees C, for 15, 30 and 45 min (n = 104 for each resin sample). Color (DeltaE) and brightness (DeltaL) changes were analyzed by spectrophotometry using the CIE Lab system and surface changes by Scanning Electron Microscopy (SEM). R1 showed more intense color changes after heat exposure than R2. DeltaL values were found to be the best parameter for evaluation of light and color change. A biphasic pattern after thermal exposure was detected, from dark brown to light white. SEM showed more intense alterations in R2 than in R1. These results indicate that the parameters observed in both resins are useful as a guide in forensic analyses. 相似文献
56.
Can Pelin M.D. Ph.D. Ragıba Zağyapan Ph.D. Canan Yazıcı M.D. Ph.D. Ayla Kürkçüoğlu M.D. Ph.D. 《Journal of forensic sciences》2010,55(5):1326-1330
Abstract: As there are cases brought for forensic examination where only the craniofacial region is available, estimation of stature from craniofacial dimensions is without doubt important in forensic cases. The study presented here attempts to estimate stature from craniofacial dimensions in the Turkish population. In the second phase of the study, the correlations between craniofacial dimensions and stature were also evaluated according to different head and face types. All measurements were taken from 286 healthy males with a mean age of 22.71 ± 4.86 years. The sample was then reclassified according to different head and face indexes. For the whole sample, correlation coefficients were low, changing only between 0.012 and 0.229. Thus, no significant increase in correlation coefficients was observed after the samples had been reevaluated according to different head and face types. As a conclusion, craniofacial dimensions are not good predictors for body height for the Turkish population. 相似文献
57.
Spanish legislation against trafficking in human beings: punitive excess and poor victims assistance
Francisco Javier De León 《Crime, Law and Social Change》2010,54(5):381-409
The article seeks to provide a perspective of human trafficking as one of the fastest growing criminal activities of the last
few years in the area of organised crime and one that affects human beings’ most basic rights. In the main, the response to
the problem has been its criminal prosecution, but without tackling the issues of need that underlie this conduct and which
the traffickers take advantage of to abuse, assail and exploit the people they traffic. In this context, the evolution of
Spanish legislation in terms of the criminalisation of this problem has made it one of the most repressive, although there
is no clear evidence of its effectiveness. This punishment, which covers a wide range of criminal conducts, has not however
been accompanied by any policies to support and integrate the victims of trafficking, which has led to a large number of victims
being subjected to slavery who, in the majority of cases, fall under the control of the trafficking networks again. 相似文献
58.
59.
Francisco Ramos Romeu 《European Journal of Law and Economics》2010,30(3):267-300
Preliminary measures adopted early in litigation are crucial for plaintiffs, given existing court delays and changing economic
environment, but can also harm a blameless defendant. Therefore, some form of regulation is needed to minimize the harms that
can result and discard non-optimal measures. Law and economic scholars have suggested that courts should control requests
for preliminary measures, but this form of regulation fails to explain existing legislations, both in civil law and common
law countries. This article argues that non-optimal preliminary measures can be more efficiently filtered through a strict
liability regime, and that their judicial control should be residual. 相似文献
60.
Miguel Manuel Melo Mnica Carvalho Virgínia Lopes Maria Joo Anjos Armando Serra Duarte Nuno Vieira Jorge Sequeiros Francisco Corte-Real 《Forensic Science International: Genetics Supplement Series》2010,4(5):e153-e157
Angola is located in the African continent, in the area of southern Africa and has a population of approximately 14 million inhabitants. The Angola population has origin from Occidental and Southern Bantu people that came from the great lakes region, creating the most ever known African migration of our days.Allele frequencies for the 15 STRs loci in the AmpFlSTR Identifiler kit (D8S1179, D21S11, D7S820, CSF1PO, D3S1358, HUMTH01, D13S317, D16S539, D2S1338, D19S433, HUMVWA, TPOX, D18S51, D5S818, HUMFIBRA/FGA and including the segment of the X-Y homologous gene amelogenin) were studied for Angola population.The genotype frequency of the 15 STR loci showed no significant deviations from Hardy–Weinberg equilibrium expectations and great values for the combined power of discrimination and combined power of a priori exclusion validate the application of these markers in forensic genetics. Comparative analyses between Angola population data and other relevant population database from Africa, Europe and American are presented. 相似文献