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51.
《啊!拓荒者》是薇拉·凯瑟最有特色的一部代表作.凯瑟的宗教观影响了她对小说中人物的看法和命运安排;她对《圣经》中的某些诫律和典故的套用,丰富和充实了作品的内容;她对"叙述暴力"的适度运用,使作品产生了撼人心魄的效果.凯瑟捍卫传统的道德观,鄙视违反宗教教义的不忠与苟合.与此同时,她又对某些宗教教叉产生了怀疑,并希望对其进行改革.  相似文献   
52.
介绍了用纳米———ZnFe2 O4/SiO2 半导体材料作光催化剂 ,用分子氧催化氧化环己烷的实验 ,根据目前所建立的半导体粒子光催化反应机理的模式 ,探讨了其反应机理 ,并进一步研究了水分子以及电子或空穴捕获剂对该反应的影响。  相似文献   
53.
This article develops a general framework to describe the changes in university IPR regulations in Europe and their effects on the patenting activities of universities and on knowledge transfer processes. Understanding the effects of changes in IPR regulations on academic patenting is a complex issue, and parallels with the US case can be misleading. First, despite the general trend towards institutional ownership, university IPR regulations in Europe remain extremely differentiated and there is no one-to-one mapping to the US system. Second, it is difficult to disentangle the quantitative and qualitative effects of changes in IPR ownership regulations on academic patenting activities from the effects of concurrent transformations in the institutional, cultural and organizational landscape surrounding academic knowledge transfer. The article proposes a review and typological classification of national university IPR ownership systems on the basis of their development since 2000, and uses it to analyze the aggregate dynamics of academic patent ownership in several European countries. The analysis of patterns of ownership of academic patents shows that there has been a general increase in university patenting since 1990, with a significant slowdown (and even reduction in some countries) after early 2000s accompanied by a switch in academic patents ownership in favor of university ownership though preserving the European specificity of high company ownership of academic invented patents.  相似文献   
54.
以十六烷基三甲基胺为模板剂,钛酸正四丁酯为钛前驱体,草酸铌为铌的前驱体,用溶胶一凝胶手段,将铌元素引入到介孔二氧化钛体系中,制备出了介孔NbzO5Ti02复合氧化物。采用XRD、IR等表征手段对其进行表征,并以苯酚为目标降解物进行了光催化反应活性测试。结果表明:少量铌能进入TiO2骨架,样品保持介孔结构,当铌量进一步增加时,介孔结构遭到破坏;铌的掺杂并不能使介孔TiO2分子筛的光催化活性提高。  相似文献   
55.
One hundred and sixty-five high school students in the Virgin Islands were asked to rate the extent to which they associate each of 62 behaviors with their concepts of “success,” “joy,” and “satisfying expectations.” They were also asked to rate the frequency with which they performed each of the behaviors. Results indicated that Virgin Islands students associate the word “success” not with academic behaviors, but with being modern, attractive, and nurturing. Moreover, individual students are less apt to perform those behaviors which Western teachers believe lead to academic success and more apt to perform those behaviors which the sample as a whole associates with being successful. The data indicate that although many Virgin Islands students enjoy traditional island activities, they do not feel successful when they engage in them. The results of the investigation are interpreted within the context of what is known concerning achievement behaviors of middle-class American youth, and implications are drawn for the teaching of young persons from diverse cultural backgrounds who attend classes conducted in the Western mode.  相似文献   
56.
College undergraduates read a 2400-word passage, responded to 16 multiple-choice questions, and received one of four types of feedback following their responses. Complexity of feedback was inversely related to both error correctability and criterion efficiency taken as a ratio of feedback study time to post-test corrects. The results were discussed in terms of depth of processing and instructional comprehension.  相似文献   
57.
Previous research has indicated that the keyword method of vocabulary learning facilitates students' performance not just on simple tests of definition recall, but on comprehension-demanding tasks as well. The present study was conducted to determine whether the “comprehension” finding could be accounted for by keyword subjects' superior definition recall per se. The results generally supported that conclusion: When conditions and subjects within conditions were equated with respect to their initial levels of definition recall, the comprehension advantage of keyword subjects disappeared.  相似文献   
58.
介绍了Lambert W函数的代数及图像性质,如该函数的级数展开式、微分及函数在复平面的图像等。总结了其在数学、物理、化学和生物等领域的应用情况。  相似文献   
59.
奥康纳在经典短篇小说《好人难寻》中,通过塑造几个无名、无声、愚昧、伪善的女性受害者形象,呈现了一个人性扭曲、信仰缺失、道德堕落的危机重重的美国南方社会,表达了她对现代社会精神危机的高度关注和深刻思考。  相似文献   
60.
Knowledge production and scientific research have become increasingly more collaborative and international, particularly in pharmaceuticals. We analyze this tendency in general and tie formation in international research networks on the country level in particular. Based on a unique dataset of scientific publications related to pharmaceutical research and applying social network analysis, we find that both the number of countries and their connectivity increase in almost all disease group specific networks. The cores of the networks consist of high income OECD countries and remain rather stable over time. Using network regression techniques to analyze the network dynamics our results indicate that accumulative advantages based on connectedness and multi-connectivity are positively related to changes in the countries’ collaboration intensity whereas various indicators on similarity between countries do not allow for unambiguous conclusions.  相似文献   
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