聚羧酸系高性能减水剂的合成技术

介绍了国内外聚羧酸系高性能减水剂的研究发展现状、分子结构特征以及聚羧酸类高性能减水剂的合成方法,分析了聚羧酸系高效减水剂的不同合成技术的优缺点,认为制备具有聚合活性的大单体的技术是聚羧酸系高性能减水剂需要解决的紧迫问题,提出了聚羧酸系高性能减水剂的研究方向和研究过程面临的问题及解决措施.     

水相ATRP法合成聚羧酸类高效减水剂

以对苯乙烯磺酸钠、丙烯酸钠为原料,以2-溴丙酸为引发剂,采用原子转移自由基聚合(ATRP),在水相介质中室温条件下合成出聚羧酸类减水剂。通过红外光谱(FT-IR)、核磁共振(1H-NMR)等测试方法对聚合物的结构进行表征与分析,通过净浆流动度研究了反应时间和产物性能之间的关系。结果表明,成功地合成出了具有嵌段结构的聚羧酸类高效减水剂,并且当反应时间取24h时,产物的性能较好。     

聚羧酸类高性能减水剂发展概况

聚羧酸类减水剂是高效减水剂的新品种,具有很多良好的使用性能。通过对近年来国内外的文献综合,讨论了反应单体和聚氧烷基链的选择、共聚物相对分子质量及其分布、端基和添加量等影响因素。     

聚羧酸系减水剂在预拌混凝土中常见问题及分析

聚羧酸系减水剂作为一种新型的外加剂,具有减水率高、保塑性能好、水泥适应性强、混凝土收缩小等优点,但在掺入预拌混凝土的使用过程中,由于各种原因,引起混凝土的质量问题,合理选用使用原材料,提高聚羧酸类减水剂在预拌混凝土中的应用。     

马来酸酐在聚羧酸盐减水剂合成中的应用

随着聚羧酸盐减水剂的不断发展,马来酸酐在其合成中的应用也越来越多.根据马来酸酐与丙烯酸(以及甲基丙烯酸)各自的特性和聚羧酸盐减水剂合成的技术要求,分析了它们在合成过程中的作用和主要差别,并概述了马来酸酐在合成中的应用情况,最后提出了马来酸酐在合成中应用的几点建议.马来酸酐及其酯的分子结构和化学活性独特,应用于聚羧酸盐减水剂的合成必将有广阔的前景.     

聚羧酸系高效减水剂的研究现状和应用前景

高效减水剂的研究已成为混凝土材料科学中的一个重要分支,并推动混凝土材料向高强、高性能化不断发展,其中聚羧酸系高效减水荆是新一代绿色高效减水剂的代表.结合国内外资料综述了聚羧酸系高效减水刑的研究现状、性能特点、分散稳定机理以及今后的发展方向.指出对聚羧酸系高效减水剂的基础理论研究还有待进一步加强;开发、合成、生产多元化和不同性能的系列聚羧酸系减水荆母体、多功能的聚羧酸系减水剂衍生产品,已成为当今聚羧酸系高效减水荆发展的必然趋势.     

苝四羧酸类有机光电材料研究进展

近年来，苝四羧酸类衍生物曾被广泛研究以应用于有机光电材料。本文中就四羧酸类衍生物的光电性质、光致电子转移过程和作为光电分子器件的研究等方面进行了评述。     

聚羧酸系减水剂的构性关系及其作用机理研究

聚羧酸系减水剂作为一种高性能减水剂,目前已成为国内外研究与发展的热点。概述了近几年国内外高效减水剂的研究与发展现状,阐述了聚羧酸系高效减水剂的分子结构、性能特点及作用机理,分子主链上阴离子基团越多及聚氧乙烯长侧链越长,聚羧酸系减水剂的分散性能和流动保持性能越好。聚羧酸系减水剂主要依靠聚氧乙烯长侧链的位阻效应和羧基及磺酸基的静电斥力来分散水泥颗粒。最后,提出了减水剂在应用中存在的问题并展望了其发展趋势。     

聚羧酸类高效减水剂的研究进展

聚羧酸高效减水剂是高效减水剂的新品种，具有很多良好的使用性能。通过对近年来国内外的文献综合，讨论了反应单体，聚氧烷基链和端基的选择，聚合物相对分子质量及其分布，减水剂添加量等对减水剂性能的影响因素。     

聚羧酸混凝土减水剂的研究现状与发展趋势

聚羧酸减水剂的研发和推广是混凝土材料科学中的一个研究热点,推动混凝土材料向高强、高性能化不断发展.结合国内外资料综述了聚羧酸系高效减水剂的研究现状、作用杌理、合成方法,分析了聚羧酸减水剂结构与性能的关系,总结了当前研究与应用中存在的主要问题,展望了今后的发展趋势.     

Recent computer-related design in the USA

The paper looks at the current research in computer-aided design at US universities. Design research in the US has increased dramatically in the last four years. The major sponsoring agencies for this research are named, as are the conferences and journals where the results of this research are presented. Emphasis is placed on research dealing with the design process itself. The areas of new design theories and methodologies, feature-based modelling, and knowledge-based CAD systems are included. Concurrent engineering is becoming a prominent research area.     

Research Trends in Information Technology Applications in Construction Safety Engineering and Management

Through analysis of articles published from 2000 to March 2014 in Automaton in Construction (AUTCON), an international research journal published by Elsevier, this paper summarizes the topics of research and the institutions worldwide where research was conducted in construction safety engineering and management. Seventy-one articles published during this time focused on Information Technology (IT) applications in this field were selected for analysis. The underlying research topics and their related IT implementations are discussed, and research trends in allied specialties are identified.     

基于Web of Science数据库的感性研究的文献计量分析

近年来,诞生于日本的感性（Kansei）研究越来越得到各国不同领域学者的关注。利用文献计量学的方法对Web of Science 数据库1998~2010年来收录的354篇相关文献进行了分析：通过对文献和作者的统计分析,探索了感性研究的发展现状;通过对文献作者提供的关键词的分析,构建了感性研究主题框架。结果表明：感性研究是一个具有较强发展潜力的新兴领域,日益呈现出跨行业、跨学科及多学科的研究特色。本研究成果对我国的感性研究具有一定的借鉴。     

集成微光机电系统研究现况及其产业化前景

本文介绍了国际集成微光机电系统的研究现况及其产业化前景 ;在此基础上 ,提出了对我国加快这一领域的研究和产业化的看法     

碱金属稀土及其掺杂卤化物的合成和光谱学性能研究

在本课题组研究的基础上,结合国内外近几年的研究报道,从碱金属稀土及其掺杂卤化物的合成方法和光谱学性能测试的角度出发,对该类化合物的合成类型,光谱学性能和材料用途等进行了介绍,并对该类化合物今后的应用前景进行了展望。     

耐超高温铱合金强韧化技术研究进展

概括地论述了铱的特点,说明了探索研究铱的强韧化技术的重要性.系统地综述了国内外在铱强韧化技术方面的研究思路、取得的研究结果以及最近的研究焦点,对耐超高温铱合金强韧化技术提出了新的研究思路,阐明理论计算的方法将是铱的强韧化技术研究的热点和有效方法.最后展望了耐超高温铱合金的发展和应用前景.     

长余辉发光材料的研究进展

长余辉发光材料因其具有特殊的储能发光性能,是一类绿色环保型材料.综述了主要体系长余辉发光材料的研究历程,总结了长余辉材料的制备方法和余辉效应,概括了长余辉发光研究上存在的问题,提出了今后研究和应用的发展方向.     

A review on the buyer–supplier dyad relationships in sustainable procurement context: past,present and future

Sustainable development is currently being applied in most fields of research. Procurement, focused on the buyer–supplier dyad, is one such discipline where sustainability is being widely applied. This paper provides a review of these research studies, conducting a systematic content analysis in order to present the state of the art in this domain. The paper carries out a detailed review of articles in international scientific journals and well-known international conferences related to green and sustainable supplier selection published between 2008 and 2014 inclusive. Seven designed research questions are proposed and answered based on this bibliography. Interesting results are reported in each section and gaps in the current body of literature are identified. The purpose of this review is to provide important future directions and limitations in this research topic.     

Scientometric Studies and Their Role in Research Policy of Two Research Councils in the Netherlands

In the past 30 years various scientometric analyses have provided input data for research policy objectives of research institutions in the Netherlands. In this article we discuss several pioneering studies performed on behalf of the research councils for physics (FOM) and technical sciences (STW), which have played an important role in the early development of scientometrics in this country. The motives for these studies, the results and the influence on research policy are discussed. Relations to present themes in scientometric investigations are drawn.     

Costs and benefits to Sweden of Swedish road safety research

This paper summarises a study designed to answer the following question: what are the benefits to Swedish society of road safety research in Sweden funded by the Swedish Transport Research Council and the programme for vehicle safety research during the period 1971-2004? The paper starts by discussing whether research can answer this question at all and explains why a well-controlled study was not feasible. A case study approach was selected, and five major research projects were examined in detail for the purpose of trying to estimate their effects on road safety. Estimates of safety effects were developed for four of the projects, indicating that road safety measures that were at least to some extent based on the findings of the research projects have made major contributions to reducing the number of road accident fatalities in Sweden. The estimates are not analytically rigorous and should be treated as qualified guesses only. Causal inferences are not possible. Nevertheless, if taken at face value, they show that the benefits to society of road safety research are large and outweigh by a wide margin the costs of the research, and of the road safety measures developed as a result of research. Thus, even if the estimated safety benefits exaggerate the true effects, the benefits of applied road safety research are likely to be greater than the costs of conducting this research and implementing road safety measures developed by research.