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排序方式: 共有597条查询结果,搜索用时 15 毫秒
51.
BJ Daly D Berry JJ Fitzpatrick B Drew K Montgomery 《Canadian Metallurgical Quarterly》1997,45(5):209-214
Assisted suicide is an issue of great importance to nurses. This issue reflects our values and beliefs as a society, calls for a clear and precise response as a profession, and challenges individual nurses to think about their own moral views. The history of the debate and the compelling moral arguments on both sides attest to the complexity of the issue and also suggest that it will not soon be resolved. The current position of the profession, as expressed in the ANA Code for Nurses and a specific position statement, were reviewed. The dilemma faced by the individual nurse who perceives an obligation to adhere to the guidelines specified by his or her profession's code and yet whose conscience dictates an act in violation of this code has been discussed as an instance of conscientious objection. While this analysis has been necessarily brief, it was intended to illustrate the importance of being clear about one's personal moral views and equally clear about one's duty to fulfil the obligations stemming from the profession's public statements. It is essential that the profession continue to explore the moral issues involved in requests for assistance in dying and provide additional guidelines for practicing nurses, with sound rationale for the profession's position. 相似文献
52.
While various types of capital have been identified and studied as drivers of economic development, recent arguments surrounding social capital in particular have led to calls for greater attention to its role in economic development within a country. Thus, we examine social capital relative to its impact on economic development at the country level. We employ a generalized social capital index (based on measures of trust, associational activities, and civic norms) to test hypotheses suggesting a positive relationship between social capital and economic development, while also considering the impact of social capital on entrepreneurship and on human capital as intermediary effects on economic development. In general, we examine the relationship between core constructs of social capital and economic development within and across 47 selected countries. Findings reveal strong support for the hypothesized relationships, with important implications for policy direction and future research. 相似文献
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54.
A copper-based active brazing alloy containing a high titanium content was produced by an electroless coating technique. Particles with a narrow density distribution were produced by deposition of nano-copper on a fine titanium powder. Both conventional titanium powder and sponge titanium were studied. The effects of pH and time on copper deposition were investiguated.Higher pH was found to increase the quantity of copper deposited. Using multiple depositions, a copper-titanium ratio of 75 wt% copper-25 wt% titanium could be achieved after several platings for pH varying between 12 and 12.8. The particle size distribution of the composite powder shows uniform growth of the copper shell and no agglomeration under pH 12. Major agglomeration of the final powder was observed for a bath pH of 12.8.Complete melting of the composite powder has been studied by DSC and the sessile drop technique. Melting began within the diffusion zone formed at the interface through the Cu4Ti → Cu(s) + L peritectic reaction that occurs at 885∘C. The melting process continued by successive peritectic reactions and dissolution of the remaining elements of the diffusion couple. The wetting behavior of this alloy was evaluated on different ceramic substrates (Al2O3, Si3N4) and found to be similar to literature observations. 相似文献
55.
Construct validity is one of the most central concepts in psychology. Researchers generally establish the construct validity of a measure by correlating it with a number of other measures and arguing from the pattern of correlations that the measure is associated with these variables in theoretically predictable ways. This article presents 2 simple metrics for quantifying construct validity that provide effect size estimates indicating the extent to which the observed pattern of correlations in a convergent-discriminant validity matrix matches the theoretically predicted pattern of correlations. Both measures, based on contrast analysis, provide simple estimates of validity that can be compared across studies, constructs, and measures meta-analytically, and can be implemented without the use of complex statistical procedures that may limit their accessibility. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
56.
N. Al-Aqeeli G. Mendoza-Suarez A. Labrie R.A.L. Drew 《Journal of Alloys and Compounds》2005,400(1-2):96-99
Al–Mg and Al–Mg–Zr alloys were processed by mechanical alloying. The phase constitution of the powders was strongly dependent on the composition of the starting mixture. In as-milled powders, an Al(Mg) solid solution was formed with up to 40 at% Al, which after annealing transformed to the equilibrium β-Al3Mg2 phase. For high Mg concentrations (60–90 at%) the dominant phase was γ-Al12Mg17 in accordance with the equilibrium phase diagram. The addition of Zr led to the appearance of Zr–Al intermetallics causing Mg to precipitate out of the Al(Mg) solution. The effect of zirconium was also to refine the structure and to retard grain growth. 相似文献
57.
Storm water runoff is perceived as a major source of pollutants that results in adverse environmental effects, but large-scale assessments are rarely conducted. The problem is particularly pronounced in southern California where 17 million people have rapidly developed coastal watersheds. The goal of this study was to make regionwide estimates of mass emissions, assess the relative contribution from urbanized watersheds, and compare pollutant flux from different land uses. A geographic information system-based storm water runoff model was used to estimate pollutant mass emissions based on land use, rainfall, runoff volume, and local water-quality information. Local monitoring data were used to derive runoff coefficients; over 1,700 storm water sampling events were used to calibrate and validate annual loadings. An average rainfall year produced 1,073×109?L of runoff, 118,000 metric tons (MT) of suspended solids, 1,940 MT of nitrate-N, 108 MT of zinc, and 15 kg of diazinon. The majority of mass emissions were from urbanized watersheds except for suspended solids, total DDT, and chlorpyrifos. Agricultural areas had the greatest fluxes for pesticides, including total DDT and chlorpyrifos while open areas typically had the smallest. 相似文献
58.
Patrick M. LaheyDonald A. Drew 《Chemical engineering science》2002,57(24):5161-5173
Perturbation methods are used to study the bifurcation of Couette flow to Taylor vortices in the presence of a small amount of suction flow through the inner cylinder. Taylor vortex flow is described as a small amplitude expansion of the velocity and pressure near the critical Gortler parameter. The suction flow modifies the critical G?rtler number, stabilizing the original Couette flow. 相似文献
59.
Luciana Porter Bolland Allan P. Drew Carmen Vergara-Tenorio 《Landscape and urban planning》2006,74(3-4):223-241
An analysis of the natural resource management system was carried out for the ejido X-kanha located in the northern part of the Calakmul Biosphere Reserve in Campeche, Mexico. Through field research using participatory rural appraisal (PRA), the activities carried out by different user groups were identified. Gender roles as well as age roles were analyzed. Results show that each family depends upon the diversification of productive activities in order to meet economic needs. Diversification of activities is carried out in both space and time, making use of different ecosystems during varied seasons throughout the year. Women's activities correspond to housekeeping and house administration; they take care of home gardens and are responsible for water collection and wood gathering. Men carry out the activities of working in the milpa, cattle raising, honey production, chicle collection, and wood felling.A series of PRA activities carried out with the people of X-Kanha led to the identification of limitations to more optimal uses of natural resources. The characterization of limitations and associated alternatives is used to provide a guideline to aid the efforts of NGOs and other organizations interested in the conservation of natural resources, and for the well-being of the local population. 相似文献
60.