催化光度法测定茶叶中铁     

张振华 《邵阳学院学报(社会科学版)》2003,2(5):79-80

在HCl介质中在Fe(Ⅲ)催化作用下H2O2氧化S酸(即1-氨基-8-萘酚-4-磺酸)使之变色，变色程度与Fe(Ⅲ)的存在量之间有良好的线性关系，借此建立了新的催化光度法．本法操作简单，重现性好，选择性高，用于茶叶中铁的测定，结果满意。  相似文献   

论《屈赋》中的几种动宾关系     

王大年 《河北师范大学学报(哲学社会科学版)》2001,24(1):93-96

:《屈赋》中除支配与被支配以外的几种动宾关系 ,即通常所说的使动、意动、处动、为动、对动、被动等 ,是古汉语中常见的一些语法现象 ,熟练地掌握和运用它 ,阅读古籍中遇到的许多疑难便能迎刃而解  相似文献   

《啊,拓荒者!》中人物形象的生态女性主义分析     

王秀艳 《昭通师范高等专科学校学报》2007,29(6):29-32

从生态女性主义的视角分析《啊,拓荒者!》中的人物形象,从女主人公对待自我女性身份和与其他女性的关系等来分析其女性意识,从她对待土地的态度来分析其自然观,结果表明:女主人公由于受到父权制世界观和人类中心主义的影响,缺乏对女性身份及自然的正确认知,因而性格中曾经存在着男权倾向,排斥女性身份并以征服和利用土地来满足自我利益;但随着其认知的深入,主人公逐渐接受自我身份,并产生了对人类与自然相互依存关系的深层认知。  相似文献   

Incubator firm failure or graduation?: The role of university linkages     

Frank T. Rothaermel  Marie Thursby 《Research Policy》2005,34(7):1076-1090

One of the theoretically important factors for incubator firm performance is the strength of their linkages to the research university sponsoring the technology incubator. Herein, we focus on two types of university linkages to the sponsoring institution: a license obtained from the university and a link to university faculty, while controlling for incubator firm linkages to non-sponsoring research universities, among other factors. We propose that a university link to the sponsoring institution reduces the probability of new venture failure and, at the same time, retards timely graduation. Further, we suggest that these effects are more pronounced the stronger the university link. Due to the difficulty of obtaining fine-grained longitudinal data, the incubation literature is characterized by a dearth of studies focusing on incubator firm differential performance. We attempt to take a first step towards closing this gap by testing these hypotheses through following 79 start-up firms incubated in the Advanced Technology Development Center at the Georgia Institute of Technology over the 6-year period between 1998 and 2003. We find broad support for the hypotheses advanced.  相似文献   

Does technological diversification promote innovation?: An empirical analysis for European firms     

Maria Garcia-Vega 《Research Policy》2006,35(2):230-246

This paper analyses the impact of technological diversity on innovative activity at the firm level. The empirical study on a panel of European R&D active companies shows that both R&D intensity and patents increase with the degree of technological diversification of the firm. Possible explanations are that, on the one hand, a firm that diversifies its technology can receive more spillovers from other (related) technological fields. On the other hand, diversification can reduce the risk from technological investments and it creates incentives to spend more on R&D. The paper provides empirical evidence relevant to the diversity-specialization innovation debate.  相似文献   

The network of innovators in Jena: An application of social network analysis   总被引：5，自引：0，他引：5  

Uwe Cantner 《Research Policy》2006,35(4):463-480

We apply social network analysis methods to describe the evolution of the innovator network of Jena, Germany in the period from 1995 to 2001. We find this evolution to be directed towards an increasing focus on core competencies of the network. Further we analyse the network resulting from R&D cooperations and explain - by means of network regression techniques - that the job mobility of scientists and the technological overlap between the actors, rather than past cooperations, can best predict the resulting structure.  相似文献   

Networks of inventors and the role of academia: an exploration of Italian patent data   总被引：3，自引：0，他引：3  

Margherita Balconi  Francesco Lissoni 《Research Policy》2004,33(1):127-145

This paper proposes a quantitative analysis of social distance between Open Science and Proprietary Technology. A few general properties of social networks within both realms are discussed, as they emerge from the new economics of science and recent applied work on “small worlds”. A new data-set on patent inventors is explored, in order to show that social networks within Proprietary Technology are much more fragmented than Open Science ones, except for science-based technologies. Two propositions are then put forward on the “open” behaviour expected from academic inventors, namely university scientists getting involved in Proprietary Technology networks by signing patents. Both propositions are confirmed by data, which show academic inventors to be more central and better connected than non-academic ones. The database and methodology produced for this paper are suggested to be relevant for the more general debate on the role of geographical and cognitive distance in university-industry technology transfer.  相似文献   

燃料电池     

王筱武 《科技通报》1999,15(3):242-243

论述了燃料电池的原因,详细分析了燃料电池的特点和类型,并对其发展前景作了展望。  相似文献   

中国诸葛菜属(十字花科)新分类群   总被引：4，自引：0，他引：4  

谭仲明  许介眉  赵炳祥  张小亮 《中国科学院研究生院学报》1998,36(6):544-548

  相似文献   

沙田柚果实贮藏期水分变化与枯水的关系     

刁俊明 《嘉应学院学报》1999,17(3):83-87

沙田柚采后经预贮10d贮藏于常温室内.用~3H_2O对标记定期测定果蒂部、果皮、果肉(汁胞)的放射性比活度和果实的失重率、果汁率、不同组织含水量、呼吸速率及营养物质含量变化,结果表明,沙田柚贮藏期间,果瓣之间、果肉和果皮之间水分是相互流动的.果实枯水时,水分从果肉到果皮的转移速度大于正常果.沙田柚果实枯水的原因可能是果肉营养物质消耗和果皮组织相对再生长同步进行.  相似文献