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21.
催化动力学光度法测定痕量钒(V) 总被引:1,自引:0,他引:1
贾欣欣 《北京城市学院学报》2002,(1):59-61
研究了在酸性介质中痕量钒催化 H2 O2氧化抗坏学酸体系的反应和动力学条件 ,建立了催化动力学光度法测定痕量钒的新方法。该方法的检出限为 0 .0 5 ng/ m L ,线性范围为 0~ 0 .5μg/ 2 5 m L ,该方法用于水样及人发中痕量钒的测定 ,结果令人满意 相似文献
22.
Pilar Beneito 《Research Policy》2006,35(4):502-517
The standard empirical framework for analysing the R&D-patents relationship is widened both by examining the different role of in-house and contracted R&D in the innovative performance of firms, and by considering patents and utility models counts as measures of innovation output. Patents and utility models are considered to approximate for significant and incremental innovations, respectively. Applying count data econometrics to a panel data set of Spanish manufacturing firms surveyed in the period 1990-1996, a transcendental production function is estimated, which allows for non-constant elasticities of the R&D inputs. The results indicate that significant innovations are mainly gestated in-house, whereas contracted R&D seems more orientated towards innovations of incremental nature. 相似文献
23.
Catherine D.F. Corolleur 《Research Policy》2004,33(4):631-642
This paper examines how scientific and technological (S&T) human capital is transformed into financial capital through the creation of firms by scientists. The analysis is based on a database describing the positions held by 132 founders from 62 French biotech SMEs. It shows that star scientists engage in highly risky but also valuable firms. Less famous scientists must develop their human capital rather than valorising a stock. The paper concludes by pointing to three paradoxes concerning the commitment and compensation scheme of star scientists and the managerial position of less known scientists. 相似文献
24.
Roger Svensson 《Research Policy》2007,36(7):1052-1069
Using a unique database on Swedish patents owned by small firms and individuals, survival models estimate how different factors influence the decision to commercialize the patents. Such an analysis has seemingly never previously been undertaken. Since the owners know more about the patents than potential external financiers, problems related to asymmetrical information are present. To overcome these problems when inventors and small technology-based firms need financing, Sweden has for a long time relied on government support rather than private venture capital firms. The empirical results show that the larger is the share of patent-owners’ costs covered by government financial support during the R&D phase, the lower is the probability of patents being commercialized. This lower degree of commercialization is likely to depend on (1) the soft terms of the government loans, where the patent owner can avoid paying back the loan if the patent is never commercialized and/or (2) that the government is not able to select promising projects. The first explanation is related to moral hazard and the second one to adverse selection. The policy suggestion is for government to change the design of the loans, to base them on firms rather than projects. 相似文献
25.
The yeast strain (Y18) was isolated from a soil sample collected from Fildes Peninsula, Antarctica. The strain is a psychrophilic yeast with optimum and maximum growth temperatures of 10 ℃ and 18 ℃, respectively. Teliospores were formed after 7 d on malt agar, when the germination of teliospores was observed. Both inositol and D-glucuronate were assimilated. Positive results of the DBB (diazonium blue B) color reaction, urease test, and starch formation were observed. The major CoQ is Qs. All results indicated that Y18 belongs to the genes of Mrakia. The 18S rDNA sequence analyses showed that Y18 is closely related to Mrakiafrigida. DNA-DNA relatedness study, and some biochemistry characteristics indicated that Y18 represents a new species for which Mrakia psychrophila sp. nov. is proposed. 相似文献
26.
严航 《十堰职业技术学院学报》2011,24(1):107-109
随着我国汽车产业生产消费的快速发展,将电子产品加载到汽车上已逐渐成为汽车后市场的首选新装备,本文侧重研究具有系统稳定性与实时信息数据处理精确性的车载时钟控制系统,将DS18B20应用于传统的车载时钟系统,通过单片机实现控制,在Proteus仿真平台验证了系统运行的准确性与可靠性。系统硬件简单可靠,成本低,软件编程容易,可方便地移植。 相似文献
27.
刘杰 《安徽广播电视大学学报》2011,(3):119-122
"九一八"事变牵涉各方远东外交政策,美国作为远东拥有重要利益的大国,其外交政策走向对国际局势具有重要作用。最终,在日本的武力下,美国所构建的华盛顿体系逐渐走向了破产。 相似文献
28.
莫镇湖 《常熟理工学院学报》2011,25(7):102-104,121
“九一八”事变后,以胡适为首的北方知识分子以《独立评论》为阵地,对该事变给出自己的建议,期望国民政府能在国联的监督之下直接进行谈判,以空间换时间,大力发展国家实力,并幻想日本主动让步。但最终这些建议都没被采纳或实现,证明了这些知识分子的理想化及其对侵略者认识的不足。 相似文献
29.
以溴化十六烷基三甲铵(CTAB)为模板剂,采用溶胶-凝胶法合成介孔纳米γ-Al2O3,用透射电镜(TEM)、比表面测定(BET)、X射线衍射(XRD)、和N2的吸附-脱附技术、Zetaplus电位测定,对所得的介孔纳米γ-Al2O3进行了表征。考察了介孔纳米γ-Al2O3在静态条件下对La(Ⅲ)的吸附性能。探讨了溶液的初始浓度、pH值、时间和温度对吸附性能的影响。结果表明:介孔纳米γ-Al2O3对La(Ⅲ)有很好的吸附性能,其吸附行为符合Freundlich吸附等温式。 相似文献
30.
宁琳 《周口师范学院学报》2011,28(6):53-56
通过对奥尼尔经典作品之一《榆树下的欲望》中主要人物的分析,展现出奥尼尔的悲剧论,以及他对贪婪人性的敌对、失望和对唤起人性真实的渴望。他认为人的悲剧是由多方面因素造成的,而自身性格的弱点和缺陷是不可忽视的重要因素。故事试图向人们揭示出,当金钱成为衡量一切的标准时,人的自然情感是怎样被压抑和扭曲的。 相似文献