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1.
The main aim of the present study was to compare risk perception among Norwegians (n = 512) living in the region of Oslo. This study was part of an ERANET 13 project entitled PETRIS, Perception of transport risk in France and Norway. The data collection was carried out in January 2011. The response rate was 51 percent. The results showed that respondents, divided in two groups according to their transport mode preferences, assessed differently risk perception in public and private transportation. Respondents who preferred collective transportation assessed the probability of experiencing criminality in collective transport modes as higher than those who preferred private modes. They were also more worried of experiencing accidents, criminality, and terror attacks in collective transportation. The relationship between transport mode preferences and use, risk perception and worry are discussed.  相似文献   
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河边桑拿位于一条美丽的河边,可以全景观赏远山的景色。它建在菲多斯景观酒店附近,供酒店的客人使用。桑拿房有一面玻璃墙,朝向景区。建筑物建在地形中,除玻璃墙外,四周用青草覆盖。  相似文献   
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This article introduces a methodology for integrating geochemical data in reservoir simulations to improve hydrocarbon reservoir models. The method exploits routine measurements of naturally existing inorganic ion concentration in hydrocarbon reservoir production wells, and uses the ions as non-partitioning water tracers. The methodology is demonstrated on a North Sea field case, using the field's reservoir model, together with geochemical information (SO42−, Mg2+, K+, Ba2+, Sr2+, Ca2+ and Cl concentrations) from the field's producers. Based on the dataset, some of the ions are shown to behave almost as ideal seawater tracers, i.e. without sorption to the matrix, ion exchange with the matrix or scale formation with other ions in the formation water. Moreover, the dataset shows that ion concentrations in pure formation water vary according to formation. This information can be used to allocate produced water to specific water-producing zones in commingled production. Based on an evaluation of the available data, one inorganic component, SO42−, is used as a natural seawater tracer. Introducing SO42− as a natural tracer in a tracer simulation has revealed a potential for improvements of the reservoir model. By tracking the injected seawater it was possible to identify underestimated fault lengths in the reservoir model. The demonstration confirms that geochemical data are valuable additional information for reservoir characterization, and shows that integration of geochemical data into reservoir simulation procedures can improve reservoir simulation models.  相似文献   
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The Web Content Accessibility Guidelines (WCAG) by the Web Accessibility Initiative (WAI) has become the de-facto standard for accessibility on the Web. WCAG version 1.0 has become significant both as a practical tool and as an academic set of principles and is presently the basis of Web accessibility evaluations and guidelines in many countries. WCAG version 2.0 was released in 2008. This paper reports on a study that empirically validated the usefulness of using WCAG as a heuristic for website accessibility. Through controlled usability tests of two websites with disabled users (N?=?7) and a control group (N?=?6), it was found that only 27% of the identified website accessibility problems could have been identified through the use of WCAG 1.0. A similar analysis of conformance to WCAG 2.0 showed a marginal 5% improvement concerning identified website accessibility problems. Compensating for the low number of test subjects with confidence tests gave results that were still low (42% for WCAG 1.0 and 49% for WCAG 2.0, with 95% confidence). It is concluded from this that the application of WAI accessibility guidelines is not sufficient to guarantee website accessibility. It is recommended that future versions of the accessibility guidelines should be based on empirical data and validated empirically and that WAI expand their definition of accessibility to include “usability for all” in accordance with ISO 9241-171:2008.  相似文献   
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During the early stages following neural transplantation, host immune responses are initiated that are not normally found in the CNS including the induction of major histocompatibility antigens (MHC I and II). Previous laboratory findings have demonstrated prolonged survival of bovine chromaffin cells (BCC) in the rat CNS following transient immunosuppression with cyclosporin A (CSA) providing chromaffin cells are isolated from highly immunogenic passenger cells. To assess the influence of passenger and chromaffin cells on host MHC I and II expression, either BCC, nonchromaffin cell adrenal constituents (NCC), or adrenal medullary endothelial cells (EC) were implanted into the host. At 2 weeks postimplantation, robust BCC survival was obtained in CSA-treated animals. This correlated with low expression of MHC I at the host-graft border and the virtual absence of MHC II. Good BCC survival with reduced MHC I expression only was seen at 6 weeks postimplantation in animals transiently immunosuppressed (4 weeks). In contrast, poor survival was seen in the EC group (even with CSA treatment). In addition, marked MHC I and II expression was found in and around these grafts at 2 weeks, and was particularly intense in EC implanted animals. The results of this study suggest that nonchromaffin passenger cells in BCC preparations, most notably endothelial cells, can induce strong immune responses even in the presence of immunosuppression. Based on MHC staining, removal of these passenger cells can reduce host responses and improve long term survival of xenogeneic chromaffin cells in the CNS.  相似文献   
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A highly sensitive method to determine agonist-induced release of endogenous fatty acids from cells in culture was developed using high-performance liquid chromatography and fluorescence detection. Fatty acids were selectively derivatized with 1-pyrenyldiazomethane and separated on a LC18 reversed phase column using an acetonitrile-water gradient. The detection limit was approx. 20 fmol and the recovery of the complete method using oleic acid was 93-98%. Tumor necrosis factor alpha (TNF-alpha) increased the extracellular release of endogenous arachidonic acid (20:4n-6) from 21 to 153 pmol/well per 4 h using 2.7 x 10(6) WEHI fibrosarcoma cells. In cells preincubated with 50 microM 20:4n-6, the corresponding figures were 463 and 3379 pmol 20:4n-6/well. Simultaneously, nearly equimolar amounts of 22:4n-6 were released together with slightly lower amounts of 24:4n-6, 16:0, 16:1n-9, and 18:1n-9. Analysis of cell lipid fatty acids showed that phosphatidylcholine was the major source of the released fatty acids. TNF-alpha increased the intracellular concentration of unesterified 20:4n-6 and 22:4n-6 by 368% and 451%, respectively. This suggests that released 20:4n-6 is rapidly chain elongated to 22:4n-6. The results indicate that the present method facilitates studies on agonist-induced release of endogenous fatty acids, and that TNF-induced fatty acid release seems to be less selective for 20:4n-6 than previously reported.  相似文献   
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