聚羧酸系高性能减水剂的构性关系研究

本文通过2-丙烯酰胺-2甲基丙基磺酸钠(AMPS)与丙烯酸(AA)、聚乙二醇单丙烯酸酯(PEA)在一定条件下发生聚合反应合成含有羧基(—COOM)、磺酸基(—SO3M)、聚氧乙烯链(—OC2H4—)等侧链的高性能减水剂PC。结果表明,接枝链的密度影响超共聚物性能,通过调节极性基与非极性基比例及聚合物分子量可以增大减水性和分散性保持性能。合成共聚物掺量为0.14%时水泥浆体有较好的流动性及流动性保持性;产品达到了预期的分子结构,与国外同类产品有很大的相似性。     

聚羧酸系减水剂引入聚氧乙烯侧链的新方法

如何接枝聚氧乙烯长侧链已经成为聚羧酸系减水剂合成的核心问题。采用酯基乙氧基化的方法向聚丙烯酸甲酯中引入一定数目的环氧乙烷(EO),得到甲氧基封端的聚氧乙烯侧链。从而为聚羧酸系减水剂引入聚氧乙烯侧链提供了一种新方法。在自制的酯基乙氧基化催化剂MCT-09催化下,对不同分子量的聚丙烯酸甲酯进行了乙氧基化反应。采用红外光谱对产物结构进行了表征,通过测试皂化值来确定其链均EO加合数。     

基于1,3-二咔唑基苯/1,3,5-三嗪双极传输主体材料的合成与光电性能

为提高电致磷光双极传输主体材料的三线态能级,以1,3-二咔唑基苯作为空穴传输单元,以1,3,5-三嗪作为电子传输单元,引入非共轭的σ键柔性链为间隔基团,合成了主体材料2-(3-(3,5-二(9-咔唑基)苯基)丙基)苯基-4,6-二苯基-1,3,5-三嗪。与空穴、电子传输单元直接相连的主体2-(3,5-二(9-咔唑基)苯基)苯基-4,6-二苯基-1,3,5-三嗪的三线态能级2.61eV相比,含柔性链的主体材料三线态能级提升为2.94eV。含柔性链的主体材料表现出更优异的电致发光性能,以其为主体的蓝光电致发光器件的效率为16.2cd/A,结构相同,采用空穴、电子传输单元直接相连材料为主体的蓝光电致发光器件的效率为13.5cd/A。     

聚羧酸系高性能减水剂的合成工艺研究

通过甲基丙烯磺酸钠(M A S)与丙烯酸(AA)在一定条件下发生聚合反应合成含有羧基(-COOM),磺酸基(-SO3M)的高分子主链M A S-AA,然后再与一定分子量的聚乙二醇发生酯化反应合成含有羧基(-COOM),磺酸基(-SO3M),聚氧乙烯链(-OC2H4-)侧链的高性能减水剂PC。该减水剂具有高减水率,通过复配减水剂掺量为0.08%(固含量)时,净浆流动度可达到260 mm。     

侧链不同封端方式聚羧酸系减水剂的合成及性能研究

以甲基烯丙基聚乙二醇(TPEG)为大单体,丙烯酸(AA)、丙烯酰胺(AM)、苯乙烯磺酸钠(SSS)为小单体,多元共聚合成不同侧链封端方式PC。通过对不同侧链封端方式的PC进行有机碳含量测试、流变性能测试、净浆流动度测试等比较出不同阴离子封端的PC的性能差异。从而比较出不同类型侧链封端对PC的影响。试验表明侧链封端方式的不同对PC性能影响较大,在阴离子封端中,磺酸基的效果最好。     

潮湿基面用环氧灌浆材料的制备及性能研究

采用十八胺与乙二醇二缩水甘油醚为原料,合成两端为环氧基、中间氮原子上接有长疏水侧链的加成物,再由自制亚胺上剩余的仲胺对加成物进行封端,制备出含长疏水侧链的潜伏性环氧固化剂.并用该固化剂制备出适用于潮湿基面的环氧灌浆材料.研究了固化剂、稀释剂和促进剂对环氧灌浆材料在不同表面状况下力学性能的影响.结果表明,该环氧灌浆材料具有在干燥和潮湿基面可操作时间长、剪切强度和粘接强度高等优点.     

高强度自乳化型双组分水固化聚氨酯防水涂料的研制

采用磺酸基聚酯多元醇做亲水扩链剂,制备了高强度自乳化型水固化聚氨酯防水涂料;讨论了预聚体中—NCO含量、扩链剂用量和用水量对涂料性能的影响,结果表明,当预聚体中—NCO含量为4.0%~5.5%、扩链剂用量为1.5%~2.0%、用水量在10%~20%时,制得的聚氨酯防水涂料的综合性能较好。     

含不饱和聚醚侧链的聚羧酸类高效减水剂的研究

本文首次采用一种新型的不饱和聚醚大分子单体,在引发剂作用下,与甲基丙烯磺酸钠和丙烯酸共聚,合成了一种含磺酸基、羧酸基和聚醚侧链的聚羧酸类高效减水剂,其结构具有新颖性。通过实验发现,此高效减水剂有高减水率、低塌落度损失和低引气量等特性。研究表明,采用将不饱和聚醚的链结构引入聚羧酸类高效减水剂的大分子链中的合成方法合成的这种新型高效减水剂有很好的发展前景。     

鹅绒藤属植物甾体成分及其药理作用研究进展

鹅绒藤属植物在我国分布广泛,且大部分具有药用价值.甾体皂苷,该属植物的主要成分,表现出极大的结构多样性.化学结构多样性体现在母核(甾体苷元)、母核取代基、糖链长度、单糖种类、绝对构型(D或L)以及糖链中糖苷键的类型(α或β),特别是在同一个糖链中同时存在D-糖和L-糖的情况在其它天然产物中并不多见,糖链长度多达7个单糖的结构在糖苷类化合物中也十分罕见.从母核和其取代基的角度将2007-2014年从该属植物中分离出来的新甾体皂苷共119个,归纳为5种17亚种.同时也对该属植物甾体皂苷的生物活性如抗肿瘤、抗病毒、神经保护和杀虫等进行了综述.     

地铁铺轨基标高程计算程序设计与实现

针对地铁线路高程设计及铺轨基标测量的特点,在充分考虑断链、竖曲线、曲线超高等因素的前提下,提出批量计算地铁铺轨基标高程的自动处理算法,实现了一次完成全线或任意里程铺轨基标高程计算,并给出了应用算例。     

聚醚型聚羧酸减水剂的侧链结构对其性能的影响

采用烯丙基聚氧乙烯醚(APEG)、丙烯酸(AA)、马来酸酐(MA)及甲基丙烯磺酸钠(MAS)为单体,以过硫酸铵为引发剂,在水溶液中共聚合成了具有不同长度侧链的聚醚型聚羧酸减水剂。利用凝胶渗透色谱(GPC)测定了不同侧链结构减水剂的分子质量,进而研究了不同分子质量的聚醚型聚羧酸减水剂在水泥颗粒表面的吸附行为对水泥的分散性能和水泥早期水化的影响。结果表明,水泥颗粒对聚醚型聚羧酸减水剂的吸附具有选择性,在相同条件下,水泥颗粒会优先吸附单一侧链结构聚醚型聚羧酸减水剂中分子质量较高的减水剂分子;分子质量适中的复合侧链聚醚型聚羧酸减水剂比单一侧链和分子质量过大或过小的复合侧链聚醚型聚羧酸减水剂更容易在水泥颗粒表面上发生吸附,对水泥颗粒具有显著的分散性能,同时能够显著地延缓水泥早期水化。     

聚羧酸盐高效减水剂的合成与表征

通过自由基溶液共聚合反应、接枝反应和磺化反应,制备了一类主链带羧基、磺酸基,支链带聚氧乙烯基醚基的聚羧酸盐高效减水剂。讨论了主链分子量、侧链长度、磺化度等因素对聚羧酸盐减水剂性能的影响,用红外光谱和凝胶渗透色谱表征了其结构,并考察了产品对水泥净浆流动度和混凝土减水率的影响。结果表明,本研究制备的减水剂对水泥粒子有较好的分散作用,混凝土减水率可达30%以上。     

Biomagnification of organic pollutants in benthic and pelagic marine food chains from the Baltic Sea

The trophic transfer of organic pollutants with varying physical chemical properties was determined in both a pelagic and benthic food chain using delta 15N as a continuous variable for assessing trophic levels. The trophic transfer of organic pollutants through the entire food chain in terms of food chain magnification factors (FCMFs) was quantified from the slope of the regression between ln [concentration] and delta 15N. Organic pollutants with statistically significant FCMFs >1 were considered to biomagnify within the food chain, whereas those with FCMFs <1 were considered to trophically dilute. Statistically significant FCMFs >1 were found for PCB congeners and organochlorine pesticides in the Baltic food chains whereas statistically significant FCMFs <1 were found for PAHs and PCNs due to trophic dilution resulting from metabolism. FCMFs were generally greater in the pelagic food chain than in the benthic food chain. However, estimated FCMFs for the benthic food chain are likely in error, as the delta 15N method suggested a food chain structure which was not consistent with the known dietary patterns of the species. Biomagnification factors (BMFs) were additionally calculated as the ratio of the lipid normalized concentrations in the predator and prey species with adjustment for trophic level and were generally consistent with the FCMFs with BMF >1 for PCBs and organochlorines.     

建筑用水性有机硅-聚氨酯嵌段共聚物防水剂

以端羟基聚二甲基硅氧烷(PDMS)与氨烃基硅烷偶联剂(DB-912)为原料,合成了端氨烃基聚二甲基硅氧烷低聚物(NS),以此为扩链剂,自乳化法制备了水性有机硅-聚氨酯嵌段共聚物(WPSUR),考察了扩链剂类型、NS的相对分子质量对乳液粒径与薄膜拒水性的影响。     

基于EPC模式的建筑供应链风险研究

简述了工程建设中的EPC模式，建立了EPC模式下的建筑供应链体系；在供应链风险识别的基础上，设计了基于EPC模式的建筑供应链风险指标体系，并提出了相应的风险管理措施，从而提高企业的经济效益。     

Health Monitoring and Structural Reliability as a Value Chain

A value chain is defined as an end-to-end solution to a problem, with the beneficiary constituting one end of the chain and the enabling technologies (or parties) making up the rest of the chain. In this context, enabling technologies such as health monitoring, damage detection, and reliability are viewed as sequential components in a chain, with each continuing the chain while adding value to it, so that the aggregate value of the chain can be delivered to the ownership. This holistic view is taken to expose a current imbalance in technology development, and the weak link corresponds to a lack of information that relates technology-investment costs to financial benefits for the owner. Structural reliability, useful life expectancy, and other information of this genre are seen to be keeping the full value of the chain from being realized and appreciated by the ownership. An example of what the desired linkage may be comes from aerospace and mechanical engineering. In the form of so-called symptom-based reliability technology, reliability is quantified for existing structures based on actual usage instead of natural age and measured symptoms instead of idealized model prediction. Hence it is also compatible with current health-monitoring and damage-detection developments (enabling technologies of the value chain). Since the value of the chain is only as (in)effective as its weakest link, it is argued that future research effort should stress balanced development throughout the chain.     

基于网络的建筑供应链集成策略

本文根据建筑供应链的特征,通过分析建筑供应链的运作流程,提出了建筑供应链的拓扑结构,为建筑供应链提供了新的解释.对照Markham等人提出的基于网络的需求链集成策略,给出了四种基于网络的建筑供应链集成策略,并以宜昌长江公路大桥为案例,分析认为建筑供应链采用基于网络的供应集成策略,要比采用理想的基于网络的供应链管理集成策略可获得更好的绩效.     

TMP改性单组分聚氨酯防水涂料的研制

摘要：在单组分聚氨酯防水涂料的合成中,引入三羟甲基丙烷（TMP）扩链剂,并与1,4-丁二醇、胺类扩链剂（6200）进行比较。结果表明：采用TMP扩链剂的聚氨酯防水涂料,其力学性能和热老化性能均较优;当TMP的添加量为0．05％,制得的聚氨酯防水涂料的综合性能最优。     

An agent-based framework for supply chain coordination in construction

Supply chain coordination has become a critical success factor for supply chain management (SCM) and effectively improving the performance of organizations in various industries. Coordination refers to the integration of different parts of an organization or different organizations in supply chain to accomplish a collective set of tasks and to achieve mutual benefits. This paper defines the concepts of construction supply chain (CSC) and construction supply chain management, especially regards construction supply chain management as the coordination of interorganizations decision making in construction supply chain and the integration of key construction business processes and key members involved in construction supply chain. Much research and practice indicate that there still are many problems in construction, most of which are supply chain problems. The research analyzes the problems in construction supply chain. In order to resolve these problems and improving the performance of construction, an agent-based framework for construction supply chain coordination is designed based on the agent technology and multiattribute negotiation and multiattribute utility theory (MAUT). The framework, which integrates the construction organizations in construction supply chain and multiattribute negotiation model into a multiagent system (MAS), provides a solution for supply chain coordination in construction through multiattribute negotiation mechanism on the Internet. Finally, the prototype of the framework is developed and tentatively run based on an imaginary construction project. The trial run reveals the feasibility to implement the agent-based framework for coordination in construction.     

基于供应链脆弱性视角的装配式建筑返工行为研究

为解决装配式建筑项目供应链上返工行为层出不穷的问题, 从供应链脆弱性视角出发, 基于暴露度、敏感度、适应度 3 个维度,建立装配式建筑供应链脆弱性与其返工行为的系统动力学模型。 运用 Vensim PLE 软件,根据供应链特性从构配件模块化程度、信息沟通积极程度等 5 个方面进行单一因素仿真分析, 结合多因素分析综合情景仿真, 证明供应链脆弱性对返工行为的显著影响。 并围绕仿真结果提出了针对返工行为的预防策略,提高装配式建筑供应链上各节点工作效率,以期降低装配式建筑返工行为,构建符合我国国情的装配式建筑供应链体系。