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31.
FeAPO-11分子筛催化氧化水溶液中苯酚的性能 总被引:1,自引:0,他引:1
以水热晶化法合成了铁磷铝分子筛FeAPO-11,并用X射线衍射分析(XRD)、扫描电镜(SEM)、紫外-可见光漫反射(UV-Vis)等对样品进行了表征,结果表明,所合成的FeAPO-11分子筛样品结晶度高,且Fe3 进入到了分子筛骨架中.进而研究了以FeAPO-11为催化剂,H2O2为氧化剂对水溶液中苯酚的催化氧化性能:在苯酚初始浓度质量200 mg/L、H2O2添加量1200 mg/L、pH值5.0、处理温度60℃、处理时间240min时,苯酚去除率达到88.72%,总有机碳(TOC)去除率达52.5%,析出到溶液中的Fe3 浓度为0.213 mg/L.重复性实验表明,催化剂的稳定性较好. 相似文献
32.
CryptoKi接口是RSA公司提出的PKCS#11标准中规定的标准加解密接口.它提供了一套独立于加密设备和操作系统的密码服务开发界面.首先简要介绍了通用CrypoKi模型,随后分析了其逻辑结构和主要接口,并提供了一个开发实例用以说明作为一个密码部件接口,CryptoKi为计算机或通信系统的安全提供了加解密基础. 相似文献
33.
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
34.
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
35.
主要针对电力系统运行过程不稳定性和危害进行分析,总结出故障的原因,进行更好的预防。11KV配电线路在我们的电网中是最主要的线路,由于他供电线路长,经过的地形长和比较复杂,所以发生单相接地的故障也较多。由于110KV配电线路采用小电流接地系统,发生单相接地时有时不跳闸,对电网影响较大,我们必须要认真对待。 相似文献
36.
37.
为了实现实验室试验环境温湿度的实时监测、多点无线测量、自动记录等功能,设计了一种实验室温湿度无线监测系统,并介绍了该系统的工作原理和硬件结构,分析了软件流程。该系统由无线单片机芯片CC1110和温湿度传感器SHT11构成数据采集端和发送模块;由CC1110、FLASH存储器、液晶显示、串行接口等电路构成数据接收模块,并与计算机连接。计算机监控程序负责处理接收模块传来的数据,并将其存储到数据库SQL Sever;通过监控画面显示实时数据和随时间变化的趋势曲线;检测员可通过计算机监控程序随时调用环境温湿度历史数据。经过实际应用证明,该系统性能良好,具有稳定、精度高、操作方便等特点。 相似文献
38.
The theory rhetoric situation put forward by Bitzer is applied to the analysis of President Bush’s address on September 11. Such these essential elements as the exigence, audience and constraints will be illustrated to reveal the cultural and religious roots behind the September 11 terrorist attack. 相似文献
39.
以新型荧光试剂2-(11H-苯[a]咔唑)乙基氯甲酸酯(BCEC-Cl)为柱前衍生试剂,采用非水毛细管电泳技术对衍生二肽进行分离.以甲醇和乙腈为溶剂,乙酸-乙酸铵为缓冲体系,采用279nm二极管阵列检测.在甲醇与乙腈体积比为7:3、乙酸铵浓度为50mmol·L^-1、乙酸浓度为0.8mol·L^-1、柱温为25℃、分离电压为28kV的条件下,实现了12种二肽衍生物的基线分离. 相似文献
40.
Ameena Ghaffar-Kucher 《International journal of qualitative studies in education》2013,26(10):1186-1202
This paper complicates the contested assumptions surrounding native research by exploring the burden of representation placed on native researchers because they are seen as insiders. This particular issue of representation is important for native researchers to consider, especially in instances where the research is on an understudied or politically charged group, because of the ways in which the socio-political climate influences both the telling and the reading of such research. Drawing on the author’s personal struggles as a Pakistani researcher conducting ethnographic research with Pakistani immigrants in the United States in the post-9/11 climate, this paper explores and critiques the role of the native researcher and the issues involved with representing understudied groups. Specifically, the paper focuses on authenticity, positionality, audience, and accountability. Thus, the paper is a call for researchers to be more reflective and to think more deeply about their positionality and its impact on the various constituents as they research and write. To encourage such reflexivity, the article provides a set of questions for researchers to consider at different stages of the research and writing process. 相似文献