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31.
In current casework, most post-cyanoacrylate stains rely on luminescence emission in the visible region (400-700 nm). While traditional stains such as rhodamine 6G work well under most circumstances, some surfaces may generate background luminescence under the same conditions. Detection in the near-infrared region (NIR > 700 nm) has shown to be effective in minimizing the interferences from such surfaces. The laser dye styryl 11 generated strongly luminescent fingermarks when applied after cyanoacrylate fuming on all surfaces tested. When compared to rhodamine 6G, the dye was superior only when viewed in the NIR. Styryl 11 was subsequently combined with rhodamine 6G, and the mixed stain formulation (named StaR 11 by the authors) induced stronger luminescence compared with styryl 11 alone with an ability to visualize in both the visible and NIR regions. Reliable and consistent results were obtained when using either styryl 11 alone or the STaR 11 mixture. The enhancement achieved did not otherwise vary depending on the source of the fingermark secretions. With visualization possible in both the visible and NIR regions, the styryl 11/rhodamine 6G mixture showed significant potential as a post-cyanoacrylate stain.  相似文献   
32.
Circumstances of criminal activities involving radioactive materials may mean fiber evidence recovered from a crime scene could have been exposed to materials emitting ionizing radiation. The consequences of radiation exposed fibers on the result of the forensic analysis and interpretation is explored. The effect of exposure to 1-1000 kGy radiation doses in natural and synthetic fibers was noticeable using comparative forensic examination methods, such as optical microscopy, microspectrophotometry, and thin-layer chromatography. Fourier transform infrared spectroscopy analysis showed no signs of radiation-induced chemical changes in any of the fiber structures. The outcome of the comparative methods highlights the risk of "false negatives" associated in comparing colors of recovered fibers that may have been exposed to unknown radiation doses. Consideration of such results supports the requirement to know the context, including the environmental conditions, as much as possible before undertaking a forensic fiber examination.  相似文献   
33.
Abstract: Determining the time since deposition of fingermarks may prove necessary to assess their relevance to criminal investigations. The crucial factor is the initial composition of fingermarks, because it represents the starting point of any aging model. This study mainly aimed to characterize the initial composition of fingerprints, which show a high variability between donors (inter‐variability), but also to investigate the variations among fingerprints from the same donor (intra‐variability). Solutions to reduce this initial variability using squalene and cholesterol as target compounds are proposed and should be further investigated. The influence of substrates was also evaluated, and the initial composition was observed to be larger on porous surface than nonporous surfaces. Preliminary aging of fingerprints over 30 days was finally studied on a porous and a nonporous substrate to evaluate the potential for dating of fingermarks. Squalene was observed to decrease in a faster rate on a nonporous substrate.  相似文献   
34.
A novel and important issue in contemporary security policy is the impact of natural disasters on terrorism. Natural disasters can strain a society and its government, creating vulnerabilities which terrorist groups might exploit. Using a structured methodology and detailed data on terrorism, disasters, and other relevant controls for 167 countries between 1970 and 2007, we find a strong positive impact of disaster-related deaths on subsequent terrorism incidence and fatalities. Furthermore, the effects differ by disaster type and GDP per capita. The results consistently are significant and robust across a multitude of disaster and terrorism measures for a diverse set of model specifications.  相似文献   
35.
Pearson correlation coefficients were applied for the objective comparison of 30 black gel pen inks analysed by laser desorption ionization mass spectrometry (LDI-MS). The mass spectra were obtained for ink lines directly on paper using positive and negative ion modes at several laser intensities. This methodology has the advantage of taking into account the reproducibility of the results as well as the variability between spectra of different pens. A differentiation threshold could thus be selected in order to avoid the risk of false differentiation. Combining results from positive and negative mode yielded a discriminating power up to 85%, which was better than the one obtained previously with other optical comparison methodologies. The technique also allowed discriminating between pens from the same brand.  相似文献   
36.
Several studies have indicated that there are potential environmental sources of particles resembling inorganic primer found in gunshot residues (GSR); as a consequence examiners are reluctant to unambiguously assign the origin of inorganic particles. If organic gunshot residues (OGSR) were found in combination with inorganic particles, the possibility of environmental sources could be potentially eliminated, thereby significantly enhancing the strength of the evidence. Methods have been previously described whereby GSR specimens can be analysed for the presence of OGSR or inorganic GRS (IGSR). However, no methods have been reported that allow the analysis of both OGSR and IGSR on the same specimen. Described in this article is a direct method using desorption electrospray ionisation-mass spectrometry (DESI-MS) for the detection of methyl centralite (MC), ethyl centralite (EC) and diphenylamine (DPA) on adhesive tape GSR stubs typically used for scanning electron microscopy-energy-dispersive X-ray (SEM-EDX) analysis. The optimisation of numerous parameters was conducted using an experimental design. The results indicate that direct analysis of these organic components of GSR is possible although some limitations were also identified. This initial investigation has also indicated that subjecting stubs to DESI analysis does not interfere with subsequent SEM-EDX analysis of primer residues; therefore the technique described herein allows a comprehensive examination of GSR that would be highly probative in the event that both OGSR and IGSR are detected in the same specimen.  相似文献   
37.
Contract enforcement is acknowledged as a major issue in Law and in Economics. Contrasting substitution and complementary perspectives with respect to the role of private vs. public enforcement institutions, this article analyses how contract law can support private institutions, and enhance economic efficiency. With multilateral agreements at stake, self-regulation and reputation mechanisms at the core of private ordering have limitations that collective organizations backed by the Law help to overcome. The analysis is substantiated by empirical data from the cattle industry. Our results suggest the need for a broader approach to contract regulation by legal scholars and antitrust-authorities.  相似文献   
38.
The author starts from the premise of the lack of genuine parliamentary control of public administrators. This deficiency in our political institutions is attributed to three reasons. First, the administrative extension gradually given to the notion of ministerial responsibility is a useless fiction for both government and opposition: partisan debate centres round policy issues, not administrative ones, and the smooth line of authority between a minister and ‘his’ civil servants is purely fictitious. Second, one can define evaluation criteria for public administration and they can be used by Parliament without risk of confusing administrative and policy issues. Under such criteria a refutable presumption of responsibility for public administrators would replace the present general assumption of non-responsibility. Third, provided adequate procedural safeguards are taken, the conceptual distinction between politicians' and civil servants' responsibility could be maintained in practice.  相似文献   
39.
This study presents the rapid screening of various high grade explosives by high performance liquid chromatography (HPLC) with monolithic stationary phases. Two gradient methods were developed, the first for quantitative analysis of eleven explosives: HMX; RDX; Tetryl; TNT; 2,3-DNT; 2,6-DNT; 3,4-DNT; 2-NT; 3-NT; 4-NT; and PETN in under 14 min. The second method separated seven explosives in under two min and is suitable for rapid screening to determine the presence of specific and/or class of explosive. The rapid screening methods were successfully applied to soils spiked with known amounts of target explosives. This technology showed excellent potential for forensic explosives detection and analysis.  相似文献   
40.
Local governments in Australia are constantly seeking to raise additional revenue to fund higher service demands. One key revenue source is service fees and charges, including fines. Premised on the notion of user pays, service fees and charges represent a significant proportion of total revenue for many local governments, especially in New South Wales, Queensland and Tasmania. This exploratory essay addresses a number of key issues related to this revenue source in order to stimulate discussion and debate on matters which are presently under‐examined in the literature. The article examines the philosophy underpinning price setting, the identification of the principles of price setting, the adoption of applicable price setting models, the need to adhere to National Competition Policy and also the applicability of differential pricing of service delivery within local government. Calls for more open approaches and enhanced disclosure relating to service provision and pricing are made.  相似文献   
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