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61.
A searchable printing ink database was designed and validated as a tool to improve the chemical information gathered from the analysis of ink evidence. The database contains 319 samples from printing sources that represent some of the global diversity in toner, inkjet, offset, and intaglio inks. Five analytical methods were used to generate data to populate the searchable database including FTIR, SEM‐EDS, LA‐ICP‐MS, DART‐MS, and Py‐GC‐MS. The search algorithm based on partial least‐squares discriminant analysis generates a similarity “score” used for the association between similar samples. The performance of a particular analytical method to associate similar inks was found to be dependent on the ink type with LA‐ICP‐MS performing best, followed by SEM‐EDS and DART‐MS methods, while FTIR and Py‐GC‐MS were less useful in association but were still useful for classification purposes. Data fusion of data collected from two complementary methods (i.e., LA‐ICP‐MS and DART‐MS) improves the classification and association of similar inks.  相似文献   
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Synthetic opioids such as fentanyl account for over 71,000 of the approximately 107,000 overdose deaths reported in the United States in 2021. Fentanyl remains the fourth most identified drug by state and local forensic laboratories, and the second most identified drug by federal laboratories. The unambiguous identification of fentanyl-related substances (FRS) is challenging due to the absence or low abundance of a molecular ion in a typical gas chromatography-mass spectrometry (GC-MS) analysis and due to a low number of fragment ions that are similar among the many potential isomers of FRS. This study describes the utility of a previously reported gas chromatography-infrared (GC-IR) library for the identification of FRS within a blind, interlaboratory study (ILS) involving seven forensic laboratories. Twenty FRS reference materials, including those with isomer pairs in the library, were selected based on either their presence in the NIST library and/or some similarity of the mass spectra information produced. The ILS participants were requested to use the Florida International University (FIU) GC-MS and GC-IR libraries supplied by FIU to search for matches to their unknown spectra generated from in-house GC-MS and GC-IR analysis. The laboratories reported improvement in the positive identification of unknown FRS from ~75% using GC-MS alone to 100% correct identification using GC-IR analysis. One laboratory participant used solid phase IR analysis, which produced spectra incompatible with the vapor phase GC-IR library to generate a good comparison spectrum. However, this improved when searched against a solid phase IR library.  相似文献   
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Jose Atiles 《Law & policy》2023,45(3):253-272
This paper explores how the use of emergency powers by the US and Puerto Rican governments exacerbated the impact of the COVID-19 pandemic and manufactured the conditions for furthering the multilayered economic, legal, political, and humanitarian crisis affecting Puerto Rico since 2006. The paper discusses three cases. First, it examines how the multiple declarations of the state of emergency, and its constant renewals, produced contradictory public health policies. Since the start of the COVID-19 pandemic in March 2020, the Puerto Rican government has issued over 90 executive orders aimed at addressing the emergency, producing an unclear, contradictory, and unequal emergency management policy. Second, the paper focuses on the impact of the passing of Law 35 on April 5, 2020, which imposed severe penalties on those who disobeyed executive orders. As a result, hundreds of Puerto Ricans were arrested, fined, and incarcerated for violating the issued order. Third, the paper studies how, citing the presence of corruption, the Puerto Rican government implemented anti-corruption and anti-fraud policies that made it more difficult for those most in need of it—mainly poor and racialized individuals, as well as immigrants and working women—to access Pandemic Unemployment Assistance. Thus, the paper argues that emergency policies designed to address the pandemic, punitive governance, and anti-corruption and anti-fraud policies undermined Puerto Rico's capacity to handle the pandemic, exacerbated its impact, and created an unequal recovery scenario.  相似文献   
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This paper draws on the results from a recent World Bank-funded project designed to inform policy-making and climate change adaptation planning in small and medium-sized cities in Latin America and the Caribbean. The focus was on floods and landslides, which are the two most common climate-related risks in cities across the region. The project allowed the application of the Urban Risk Assessment (URA) tool developed by the World Bank and the drawing of valuable lessons which may also be applicable to the many methods and tools available for climate change adaptation planning in the rapidly urbanising cities of developing countries.  相似文献   
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This study sets out to analyze and evaluate the implementation of a system for the regulation and control of social policies ("Social Comptrollership") involving civil society so as to reinforce the mechanisms for ensuring transparency and responsibility in the government's operation of social programs and the execution of public works Here is presented the analysis of the Federal Rural Housing Program (in Spanish: "Programa de Vivienda RuraF') that is aimed at providing accommodation to families in situations of severe poverty living in communities described as suffering from "high or very high levels of marginalization". The main conclusion of this research, which is based on a series of interviews with aid recipients, the officials and the social organizations involved, is that the regulatory aspects of this system for controlling social policies are not effective, since they lack mechanisms for enforcing the sanctions set down for participants who do not respect the agreements they have entered into.  相似文献   
67.
The role of cardiac inhibitory reflex as a potential cause of death is still a matter of debate. This study reports two cases of death under unusual circumstances. Case 1 corresponds to a man found hanging where the role of ligature compression of the carotid sinus became relevant as a possible explanation of death. In Case 2, the participation of a vasovagal syncope was clearly triggered by the laryngoscopic procedure. It is proposed that cardiac inhibitory reflex should be taken into account in those cases of unexpected death, which fulfills the following three criteria: (i) The investigation of the circumstances of the death is consistent with a hypothesis of cardiac arrest. (ii) A typical triggering peripheral stimulus is present. (iii) The performance of a complete autopsy cannot rule out the participation of a cardiac inhibitory reflex in the cause of death.  相似文献   
68.
The minutiae, a term coined by Galton to refer to the small peculiarities present along the length of every isolated ridge, or characteristic points, a term used primarily by the Spanish Police Scientists, have an inter- and intrapopulation variability which has not been extensively studied. However, these peculiarities constitute the bases for the fingerprint identification of individuals in the field of criminology. Using the adhesive paper and graphite method, the fingerprints of 200 students, 100 males and 100 females, with ages ranging between 20 and 35, have been taken at the University of Alcala (Madrid). From this sample, the distal phalanx of the index finger of the right hand has been studied. The total count of the minutiae, as well as that of each different type, was made of the entire print area, and inside and outside of a circle with a radius of 18 ridges. The highest frequencies were of ridge endings, followed by bifurcations and convergences, all others appearing with frequencies of lower than 5%. The distribution of the minutiae was not homogeneous for the area of the fingerprint (inside and outside the circle). In the study of minutiae statistically significant differences were found between the sexes, and between the different types of general pattern (arches, loops, and whorls).  相似文献   
69.
The purpose of this research is to investigate a method for the forensic elemental analysis of cotton fibers for the purpose of increasing the discrimination between otherwise similar cotton evidence using microwave digestion inductively coupled plasma mass spectrometry (ICP-MS) and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). A quadrupole ICP-MS and UV laser ablation (266 nm) instruments were used for the analysis. A cotton standard reference material (IAEA V-9) was used to validate the developed methods producing good accuracy with typically <10% bias and good precision (typically <5% RSD) for the element list: 25Mg, 27Al, 55Mn, 57Fe, 88Sr and 137Ba. It was found that the LA-ICP-MS method resulted in improved precision over the solution ICP-MS method. Twenty-four raw cotton samples and five white cotton T-shirts were analyzed with the developed methods. It was also found that all the raw cotton samples from different sources were distinguishable from each other, as were all the cotton T-shirts resulting in zero type I errors and zero type II errors for the pairwise comparisons. The laser ablation method was slightly faster than the solution-based analysis, requiring 3 h for the laser analysis of 10 samples vs. 3.5 h for the solution analysis, including sample preparation time. One additional advantage of the LA-ICP-MS method was the extremely low sample consumption (1.75 μg were consumed vs. 250 mg for the solution-based method) and the fact that the LA samples are amenable for reanalysis.  相似文献   
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