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This study focuses on the behavior of sodium dioctylsulfosuccinate (SDOSS) in 50/50 w/w % polystyrene/poly(butyl acrylate) (p-Sty/p-BA) latex films. Specifically, mobility and orientation are examined in the context of the film formation by the use of dynamic mechanical thermal analysis and attenuated total reflectance (ATR) Fourier transform infrared (FT-IR) spectroscopy. While for the homopolymer blends of p-Sty and p-BA, two Tg values resulting from a phase separation of p-Sty and p-BA phases are observed, only a single Tg is detected for a copolymer of the same mixture, indicating a single phase within the film. ATR FTIR spectroscopic data indicate that the phase separation of p-Sty and p-BA blends does not occur uniformly across the film. After coalescence, p-Sty particles produce a significant degree of stratification at approximately 1.6 μm from the film surface. At this depth, the polystyrene rings assume preferentially parallel orientation to the film surface. At the same time, the hydrophilic groups of SDOSS surfactant (SO3Na+) are oriented preferentiallyparallel to the surface. Under high relative humidity conditions, water is able to diffuse into the film and swells the surface layers, thus causing them to expand. As a result, the top, predominately poly-n-BA surface becomes “thicker», and p-Sty phase appears to be near 2.3 μm from the surface. The polystyrene rings maintain their preferential parallel orientation to the surface, but the hydrophilic groups of SDOSS are able to diffuse into the film with the water uptake and are thus not present at the filmair interface. © 1996 John Wiley & Sons, Inc.  相似文献   
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Through the comparative analysis on the theories and practical experience of the development of old-age care (OAC) in both China and other countries,and based on the interview and questionnaire survey in Zhejiang Province and Hangzhou City,this paper proposes the research and analysis framework for the old-age service system,i.e.,"OAC mode-OAC service system-OAC facility system." The paper argues that,oriented by OAC mode of "taking community-and home-based care as the main body and institution-based care as supplement," China should build an OAC facility system and planning thoughts that take "continuum of care" as concept and long-term care system as core.Taking Zhejiang Province and Hangzhou City as examples,the paper conducts the optimization research on current OAC facilities planning in terms of hierarchical system,scale,and differentiation,so as to formulate more systematic and operable planning standards for OAC facilities.  相似文献   
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DC‐SIGN, an antigen‐uptake receptor in dendritic cells (DCs), has a clear role in the immune response but, conversely, can also facilitate infection by providing entry of pathogens into DCs. The key action in both processes is internalization into acidic endosomes and lysosomes. Molecular probes that bind to DC‐SIGN could thus provide a useful tool to study internalization and constitute potential antagonists against pathogens. So far, only large molecules have been used to directly observe DC‐SIGN‐mediated internalization into DCs by fluorescence visualization. We designed and synthesized an appropriate small glycomimetic probe. Two particular properties of the probe were exploited: activation in a low‐pH environment and an aggregation‐induced spectral shift. Our results indicate that small glycomimetic molecules could compete with antigen/pathogen for binding not only outside but also inside the DC, thus preventing the harmful action of pathogens that are able to intrude into DCs, for example, HIV‐1.  相似文献   
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The depolymerization of coals using phenol and p-toluenesulphonic acid, was studied.In this reaction the acid ‘catalyst’ is destroyed, its rate of destruction being different for different coals. A kinetic study of the depolymerization of Bruceton coal under conditions of gradually declining acid concentration has been carried out. Parameters which were monitored include the weight increase of the products, the solubility of the products in benzene-ethanol, the extractability of the products into pyridine, the amount of colloidal material present in the pyridine-extractables, and the molecular weight distribution of the pyridine-soluble products. Under the conditions used, the reaction produces primarily polymeric products from coal. The molecular weight distribution of the pyridine-soluble material seems to undergo no major changes with reaction time.  相似文献   
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This study deals with young households at the beginning of their housing career. During the 1990s, a tendency of the young to leave the parental home at a later age than during previous decades was discussed. With extended education, rising housing costs and a shortage of rental housing, difficulties in finding an affordable place to live could be expected to have increased. Parental resources are of increasing importance in times of recession. The aim of this study was to follow the first steps in the housing careers of young individuals in a Swedish municipality and to investigate the time of nest-leaving and the choice of tenure for their first and second moves. Individuals aged 16–25 years in the municipality of Gävle, Sweden, were included in the study. Longitudinal data for the years 1985–1995 were used. To capture changes over time, the nest-leaving situations of two cohorts were compared. Results indicate that the individuals in the 1973 cohort leave home at a higher age than do those in the 1968 cohort. A surprisingly large share move into tenant co-operatives. Such moves, as well as moves into owner occupation, occurred mainly within Gävleborg County. Individuals moving to other municipalities outside the county moved to a larger extent into rental housing.  相似文献   
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项目类型:滨河公园重建设计阶段:方案设计、扩初、施工图、工程监理客户名称:奥克兰交通局客户联系人和证明人:理查·德弗斯,奥克兰交通局南部基础设施经理(09)355 3553实体工程造价:150万纽元(不包括堤岸工程)项目团队:项目负责人:加斯·法尔考纳,瑞赛特城市设计设计负责人:奥森·瓦多克,瑞赛特城市设计施工文档:艾伦·尼克尔森,瑞赛特城市设计种植设计:克莱尔·麦琪,瑞赛特城市设计暴雨工程:埃兰·斯雷特,Aurecon(第一阶段)市政与结构工程:斯科特·麦克因泰尔,Projenz(第二阶段)照明设计:安迪·瑞,样式公司引导标识:巴纳比·包斯、戴罗·包斯施工:杰夫·劳瑞,邓普西·伍德市政工程(第一阶段)施工:托尼·门罗,约翰·菲尔莫工程(第一阶段)  相似文献   
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1背景简介在澳大利亚,民用住宅已经成为碳排放增长较快的板块之一.预计在2020年,民用住宅将比1990年增加61%,因此,想要达到澳大利亚的以2000年为基准,在2020年和2050年相继减排5%和80%的目标,需要对将建的和已建的民用住宅进行大量的碳减排.2007年,为了倡导民用住宅的减排和维护国家未来的持续发展,澳大利亚联邦科学院( CSIRO)的能源转型研究中心设立了澳大利亚零碳房( AusZEH)项目,致力于展示和评估适用于澳大利亚的低碳民用住宅技术.  相似文献   
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