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31.
With rapid urbanization, big cities in the south of China are progressively falling short of sustaining outdoor thermal comfort. In this paper, a thermal comfort and energy evaluation model is derived from revisions of previous study, to simulate and predict the interaction of coupled urban building-site climate and then the thermal comfort. The methodology of principal calculations is demonstrated first, then a hypothetical district of office buildings in Shanghai is selected. Dynamic on-site climate parameters, anthropogenic heat and indoor/outdoor SET* values, etc., are simulated and evaluated. The results show the variation of outdoor SET* values influenced by factors including canopy height, building coverage and air-conditioning set-point temperature. 相似文献
32.
Multiple evaluations of the removal of pollutants in road runoff by soil infiltration 总被引:2,自引:0,他引:2
Murakami M Sato N Anegawa A Nakada N Harada A Komatsu T Takada H Tanaka H Ono Y Furumai H 《Water research》2008,42(10-11):2745-2755
Groundwater replenishment by infiltration of road runoff is expected to be a promising option for ensuring a sustainable urban water cycle. In this study, we performed a soil infiltration column test using artificial road runoff equivalent to approximately 11-12 years of rainfall to evaluate the removal of pollutants by using various chemical analyses and bioassay tests. These results indicated that soil infiltration treatment works effectively to remove most of the pollutants such as organic matter (chemical oxygen demand (CODMn) and dissolved organic carbon (DOC)), P species, polycyclic aromatic hydrocarbons (PAHs), numerous heavy metals and oestrogenic activities. Bioassay tests, including algal growth inhibition test, Microtox and mutagen formation potential (MFP) test, also revealed effective removal of toxicities by the soils. However, limited amounts of NO3, Mn, Ni, alkaline earth metals, perfluorooctane sulphonate (PFOS) and perfluorooctane sulphonamide (FOSA) were removed by the soils and they possibly reach the groundwater and cause contamination. 相似文献
33.
利用数值计算方法研究建筑内部气候与城市局地气候之间的能量及物质传递关系,寻找热舒适与节能和环保之间的平衡点具有重要的意义.介绍了改进后生成的城市局地-建筑耦合气候评价模型的主要内容和计算方法,以上海地区为例,计算了一个理想化的高层办公楼区的局地气候参数,空调系统排热及室内外新标准有效温度TS*E等.结果表明,空调时间段内室外平均TS*E值受空调设定温度的强烈影响.当空调设定温度从28℃降至22℃时,空调排热平均值增加了193 W/m2,这个增值造成室外平均TS*E提高了约0.23℃. 相似文献
34.
Kinetic Study of the Prooxidant Effect of α-Tocopherol. Hydrogen Abstraction from Lipids by α-Tocopheroxyl Radical 总被引:1,自引:0,他引:1
Aya Ouchi Masaharu Ishikura Kensuke Konishi Shin-ichi Nagaoka Kazuo Mukai 《Lipids》2009,44(10):935-943
A kinetic study of the prooxidant effect of α-tocopherol was performed. The rates of allylic hydrogen abstraction from various
unsaturated fatty acid esters (ethyl stearate 1, ethyl oleate 2, ethyl linoleate 3, ethyl linolenate 4, and ethyl arachidonate 5) by α-tocopheroxyl radical in toluene were determined, using a double-mixing stopped-flow spectrophotometer. The second-order
rate constants (k
p) obtained are <1 × 10−2 M−1 s−1 for 1, 1.90 × 10−2 M−1 s−1 for 2, 8.33 × 10−2 M−1 s−1 for 3, 1.92 × 10−1 M−1 s−1 for 4, and 2.43 × 10−1 M−1 s−1 for 5 at 25.0 °C. Fatty acid esters 3, 4, and 5 contain two, four, and six –CH2– hydrogen atoms activated by two π-electron systems (–C=C–CH2–C=C–). On the other hand, fatty acid ester 2 has four –CH2– hydrogen atoms activated by a single π-electron system (–CH2–C=C–CH2–). Thus, the rate constants, k
abstr/H, given on an available hydrogen basis are k
p/4 = 4.75 × 10−3 M−1 s−1 for 2, k
p/2 = 4.16 × 10−2 M−1 s−1 for 3, k
p/4 = 4.79 × 10−2 M−1 s−1 for 4, and k
p/6 = 4.05 × 10−2 M−1 s−1 for 5. The k
abstr/H values obtained for 3, 4, and 5 are similar to each other, and are by about one order of magnitude higher than that for 2. From these results, it is suggested that the prooxidant effect of α-tocopherol in edible oils, fats, and low-density lipoproteins
may be induced by the above hydrogen abstraction reaction. 相似文献
35.
Aya FujimotoToshiya Masuda 《Food chemistry》2012,132(2):901-906
The antioxidation mechanism of rosmarinic acid was investigated. An AIBN-induced oxidation reaction of linoleate in the presence of rosmarinic acid produced one main product. The DPPH reaction of rosmarinic acid also gave two products, one of which corresponded to the product of the lipid system. Direct isolation of the products failed because of their instability. To the DPPH reaction, the addition of 1-dodecanethiol afforded three isolable adducts. Their structures revealed that the reaction produced quinone derivatives on either the caffeoyl or 2-oxyphenylpropanoyl moieties. However, the lipid oxidation afforded one quinone, which could convert to a thiol adduct. The HPLC of the reaction clarified that the antioxidation product of rosmarinic acid was the unstable quinone on the 2-oxyphenylpropanoyl moiety. This quinone formation was the first stage of the antioxidation of rosmarinic acid in the lipid system. The odourless 1-dodecanethiol is a useful reagent to identify the unstable quinone from polyphenol oxidation. 相似文献
36.
以当代城市普遍涌现的社会隔离现象为切入点,引出上海里弄街区中出现的毗邻隔离问题,并以此展开毗邻隔离与居住混合辩证关系的论述。指出,物理空间的接近并不能带来社会层面的混合。在对历史向度的里弄变迁进行梳理之后,选取虹口港里弄街区的日常生活空间作为研究对象。通过对社区认知边界的测定和生活空间利用模式的分析,对里弄街区中有关三个世界的日常生活空间异化与毗邻隔离展开讨论。最后,在明确日常生活空间社会意义的基础上,从国与家两个维度对社区融合视角下的日常生活空间组织做出总结。认为基于物质层面的日常生活空间维系,与社会层面的社区参与和居民赋权,是当前语境下上海里弄街区修补毗邻隔离问题,实现公共空间统一的必由之路。 相似文献
37.
3-Fluorobenzoic acid adsorbed on Au(1 1 1), Au(1 0 0) and Au(1 1 0) electrodes has been investigated using in situ IR reflection spectroscopy, UV-visible reflectivity measurements, and differential capacity measurements. As determined by IR reflection spectroscopy, the vertically adsorbed 3-fluorobenzoate is the predominant species at positive potentials, and the flat-lying type is adsorbed at negative potentials. In the UV-visible reflectivity measurements, the reflectivity changes for the vertically adsorbed and flat-lying 3-fluorobenzoates on the Au(1 0 0) electrode were observed at different frequency regions. No UV-visible reflectivity signal was observed for the Au(1 1 0) electrode, and it was proved that the UV-visible reflectivity change has a strong single crystal surface dependence. For the vertical configuration, a large contribution between the 5d orbital of Au and the 2p orbital of oxygen in 3-fluorobenzoate was found for the cluster model by DFT calculation. 相似文献
38.
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40.
Kazumitsu Nawata Masako Ii Aya Ishiguro Koichi Kawabuchi 《Mathematics and computers in simulation》2009
We analyze the length of hospital stays of patients hospitalized for cataract and related diseases (Diagnosis Related Groups (DRG) 2041) in Japan, utilizing the data pertaining to 3436 patients on whom one-eye lens operations are performed. We use the discrete-type proportional hazard model to analyze variables that may affect the length of stay. 相似文献