Landscaping Attributes and Property Buyers' Profiles: Their Joint Effect on House Prices

This paper investigates the effect of environmental features on house values while focusing on the interactions between landscaping attributes and home buyers' profile. The originality of this study rests on the assumption that, while neighbourhood characteristics translate into distinct sub-markets and primarily set the structure of house prices, individual home buyers' preferences, under specific market conditions, also affect values. The study benefits from two distinct, although related data sets on the single-family segment of Quebec City's housing market: while landscaping features were obtained via an extensive field survey of houses sold between 1993 and 2000, a detailed phone survey of related homeowners' family status, age and income profiles is being conducted since 2000. Findings suggest that household profile and structure do shape landscaping preferences and that utility patterns of homeowners may be best understood by looking at interactions between the two sets of variables. Considering that population aging is a major issue for economic and social planners, such a conclusion should be accounted for in housing policy design.     

厚壳贻贝分离蛋白提取、氨基酸组成及理化特性研究

以厚壳贻贝脂溶性物质提取后的副产品-贻贝粉为原料,采用等电点沉淀法,结合乙醇/水脱酚及透析分离提取厚壳贻贝蛋白并对其氨基酸组成及理化特性进行研究。最终得到分离蛋白的蛋白含量为93.8%,氨基酸组成在提取前后无显著性变化,必需氨基酸含量丰富,约为总氨基酸的36%,其中赖氨酸、亮氨酸、苯丙氨酸、苏氨酸和缬氨酸含量较高,均可达到FAO/WHO推荐值。厚壳贻贝分离蛋白具有较好的溶解性,其持水性、吸油性以及起泡性均优于大豆分离蛋白和鸡蛋蛋白,但乳化性不及大豆分离蛋白和鸡蛋蛋白。研究结果表明,厚壳贻贝蛋白可作为一种良好的蛋白质资源,通过优化提取方法及对其理化特性研究的深入,可极大提高厚壳贻贝脂溶性物质提取后的副产品-贻贝粉的综合利用。      

Influence of hydrophobic characteristic of organo-modified precursor on wettability of silica film

The objective of this study is to design new hybrid silica materials as templates with hydrophobic properties, prepared at room temperature by a base catalyzed sol–gel process. As silica sources, organoalkoxysilanes functionalized with short hydrophobic chains were used: tetraethylorthosilicate (TEOS), methyltriethoxysilane (MTES), vinyltriethoxysilane (VTES), octyltriethoxysilane (OTES) and isobutyltriethoxysilane (iTES). It was shown that hydrophobicity of the functionalized silica nanoparticles increased as a function of length of the aliphatic chains (MTES < iTES < OTES) or when, instead of a hydrophobic alkyl chains (substituting group of silica precursors), a monounsaturated group was used (VTES). It was observed that the samples responded in a specific way to each type (hydrophilic or hydrophobic) of the dropped liquid. Even though the experiments were limited to short hydrocarbon chains, they showed that there is a threshold to reach high hydrophobicity of the hybrid surface.