液晶显示器用有机高分子材料的老化与评价方法研究

通过对液晶显示器用有机高分子材料的老化机理分析,研究了胶带和胶黏剂分别在材料贮存期间和使用期间的主要应力及其薄弱环节。提出了在有机高分子材料不同的使用阶段相应的老化试验方案和失效评价指标,并给出了相应的试验验证过程,为液晶显示器用有机高分子材料的寿命评估提供了支持。     

Design,synthesis, characterization,and aging properties of a new end-capped three-dimensional high-refractive index hybrid organic–inorganic polysiloxane

The actual need for hybrid organic–inorganic polysiloxanes is very high due to their importance in optoelectronic applications, especially for the preparation of anti- and low-reflection layers, photopatterned overcoats, flexible hard coats, and glass and metal coatings. However, such three-dimensional hybrid polysiloxanes have very often a limited shelf life and aged very rapidly. Consequently, this type of polymer may require to be stored at cold temperatures and needs to be dilute in organic solvent to a very low solid content, which are unprofitable conditions for commercialization purposes. Therefore, there is an urgent demand to prepare three-dimensional polysiloxanes, which are more resistant toward aging processes. Herein, a new hybrid three-dimensional polysiloxane has been designed and synthesized from three different silane precursors using the sol–gel technology, and characterized using gel permeation chromatography, ¹H, ¹³C, and ²⁹Si nuclear magnetic resonance and MS spectroscopies. One-fourth of the silanol groups present in the polysiloxane have been protected with chlorotrimethylsilane. The refractive index of the silicon wafer coated with the new polysiloxane was found to be 1.53, which is higher compare to traditional values. Importantly, the new protected three-dimensional polysiloxane did not age after being stored at T = 40°C for 3 weeks.     

时效温度对铝锂合金裂纹扩展方式影响的半定量研究

以2090 Ce合金为研究对象,测试不同时效温度、时间的断裂韧性,并对试样断口进行半定量分析,探讨时效工艺、断裂韧性及断裂机制之间的响应关系。研究表明,2090 Ce合金的断裂韧性试样以分层开裂为主要断裂方式。分层开裂与时效温度有密切关系,随时效温度升高,分层比例增大,厚度变薄。分层开裂亦与应力状态、晶界强度有密切关系,分层裂纹最先在三向应力的作用下于试样中心的晶界处形成,平行承载的薄板处于平面应力状态,裂尖前方塑性区扩大,消耗较多塑性变形功,从而达到增塑作用。时效温度和时间对断裂韧性临界裂纹尺寸影响很小。     

2090铝锂合金时效强化相间的耦合作用

本文利用透射电镜技术（ＴＥＭ），对１９０℃时效条件下，２０９０铝锂合金中主要脱溶相的组织特征以及相间的交互作用进行了分析研究。在对合金１９０℃时效特征研究基础上，着重探讨了合金的两个主要强化δ′（Ａｌ３Ｌｉ）和Ｔ１（Ａｌ２ＣｕＬｉ）相同以及Ｔ１相与亚晶界间的耦合作用。研究发现时效初期（３ｈ）δ′和Ｔ１相间的交互作用形式，具有不同于中、后期时效（１２ｈ和４８ｈ）的特征；亚晶界是Ｔ１相较集中的地方，而这又造成亚晶界附近的δ′无沉淀带（ＰＦＺ），本文分析探讨了Ｔ１相与亚晶界间的相互作用以及δ′ＰＦＺ出现的原因。     

Cu-Cr-Zr-Mg合金的变形时效行为

通过对Cu-0．3Cr-0．15Zr-0．05Mg合金硬度、导电率分析和显微组织观察。研究冷变形和时效处理对合金组织和性能的影响。结果表明，冷加工变形产生的位错。加速Cu-0．3CF0．15Zr-0．01Mg合金的时效过程。大幅度提高合金的导电率和硬度．在时效的初期尤为明显。合金固溶并80％形变后在470℃时效2h导电率和硬度分别达75．1％IACS和156．1Hv，60％变形500℃时效0．5h导电率和硬度分别达73．3％IACS和165．7Hv。     

Finding home after homelessness: older men’s experiences in single-site permanent supportive housing

Abstract

Although research on supportive housing models for older homeless adults is gaining momentum, few studies have considered the unique experiences of formerly homeless older adults residing in single-site permanent supportive housing (PSH). Drawing on the concepts of home and social exclusion, this qualitative case study explored the everyday experiences of 10 formerly homeless older men residing in single-site PSH. A constructivist grounded theory methodology and in-depth interviews revealed that participants felt largely at home in PSH because the congregate design and surveillance fostered a sense of safety. However, certain design features coupled with housing rules triggered processes of territorial exclusion. Further, members of minority groups experienced identity and institutional exclusion because of discrimination linked to their ethnicity, language, and sexual orientation. Recommendations are provided to promote more inclusive, home-like models of supportive housing for older homeless adults.     

建筑密封材料老化机理探讨

本文结合各类密封材料的交联反应过程和热老化、氙灯老化试验结果,对其耐久性的老化反应机理进行了探讨。     

高分子材料的老化试验

详细地介绍了高分子材料的耐候性试验、耐热性试验、湿热试验、抗霉试验、盐雾试验、耐寒试验等,以正确评价高分子材料的老化性能,对高分子材料的老化研究进行了展望,以促进高分子材料的应用。     

论施工项目经理的索赔管理

施工项目经理管理的重点是经济管理,经济管理的重点是工程索赔。文章就如何正确、合理地做好施工索赔管理工作进行论述,以供参考。