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61.
Using Psychological Abstracts as the source of the original sample (“first-level”), various characteristics of the literature of educational psychology are compared with the characteristics of a “second-level” literature (defined as the literature that the first level cites). In particular, the scatter (dispersion) of periodical articles over periodical titles is looked at for both levels. The journals most cited within the literature of educational psychology are identified. 相似文献
62.
INTRODUCTIONTherearemanymanufacturedtoolsandprod uctsfordailyusethatarefabricatedbyironsuchas:ironmongery ,ironplate,ironstrap ,ironwire ,ironstairsandotherironworks.Theseproductsimprovethelivingconditionsofourlife.Toachievethevarioususegoalsandgivespecia… 相似文献
63.
64.
秦俊嫄 《湖北广播电视大学学报》2006,23(5):53-54
美国作家菲茨杰拉德的小说《了不起的盖茨比》被认为是美国20世纪文学杰作之一。作者巧妙地选择小说的第二主人公尼克作为小说故事的主要叙述者,使整部小说取得了极好的艺术效果。本文认为小说中还有另一个隐藏的叙述者乔丹·贝克,她的叙述不仅起着补充小说故事情节的作用,而且还传达着作者的潜藏话语。 相似文献
65.
The present paper deals with a comparative karyotypic study of three species in Fri-
tillaria-F. thuncergii Miq., F. anhuiensis S. . Chen et S. F. Yin and F. hupehensis Hsiao et
K. C. Hsia. The karyotype of F. anhuiensis S. C. Chen et S. F. Yin is first reported.
The karyotypes of the three species of Fritillaria are rather similar, all with K(2n)=24=
2m+2sm+12t+4st+4m (SAT), showing a close interspecific relationship. They all have two
pairs of st chromosomes, one of which is the third chromosome in all the three species studied,
but the other is the seventh in F. thunbergii Miq, the eighth in F. anhuiensis S. C. Chen et S. F.
Yin, and the fifth in F. hupehensis Hsiao et K. C. Hsia. It tells us that there are some differences
in their karyotypes. All of the three species possess two pairs of satellite chromosomes with the
satellites located on the long arms. A heterochromatic zone is found sometimes on long arms of No.
IX chromosome in each species of Fritillaria and on one of No. I chromosomes in both F. thun-
bergii Miq. and F. anhuiensis S. C. Chen et S. F. Yin, a chromosome polymorphism occurring
between populations of Fritillaria. In addition, three B chromosomes are always found in most
root-tip cells of F. hupehensis Hsiao et K. C. Hsiao. 相似文献
66.
Two new species of the Liliaceae are described from Anhui Province, China. i. e.
Fritillaria qimenensis D. C. Zhang et J. Z. Shao and Lilium anhuiense D. C. Zhang et J. Z.Shao. 相似文献
67.
唐德礼 《十堰职业技术学院学报》1998,(1)
本文论述了用V/F变换器和VCO压控振荡器与单片机接口进行A/D转换的方法,并给出了硬件电路和转换程序.这种方法简化了硬件结构,提高了A/D转换精度,有较强的实用性. 相似文献
68.
69.
《F1速报》是目前我国最有影响力的赛车运动专业杂志,文章对《F1速报》关于F1中国大奖赛的专题报道进行研究。结果表明,《F1速报》从创刊至今的7年多时间当中,对F1中国大奖赛的报道无论是从报道力度、报道规模、报道内容的广度和深度,以及报道的后续影响力方面,都有了长足的进步。以《F1速报》为代表的赛车类专业体育媒体的迅速发展,对F1运动在中国的推广起到了巨大的推动作用。 相似文献
70.
International knowledge spillovers, especially through multinational companies (MNCs), have recently been a major topic of discussion among academics and practitioners. Most research in this field focuses on knowledge sharing activities of MNC subsidiaries. Relatively little is known about their capabilities for protecting valuable knowledge from spilling over to host country competitors. We extend this stream of research by investigating both formal protection strategies (e.g. patenting) as well as strategic ones (secrecy, lead time, complex design). We conceptualize the breadth of firm's knowledge protection strategies and relate it to the particular situation of MNC subsidiaries. Moreover, we argue that their approaches differ with regard to host country challenges and opportunities. We address these issues empirically, based on a harmonized survey of innovation activities of more than 1800 firms located in Portugal and Germany. We find evidence that MNCs prefer broader sets of knowledge protection strategies in a host country with fewer opportunities for knowledge sourcing (Portugal). In Germany, though, they opt for narrower sets of knowledge protection strategies if they invest in innovation activities themselves. We deduce that these results are due to a need for reciprocity in knowledge exchanges to benefit fully from promising host country knowledge flows. 相似文献