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排序方式: 共有792条查询结果,搜索用时 13 毫秒
781.
Shun Kawakubo Shuzo Murakami Toshiharu Ikaga Yasushi Asami 《Building Research & Information》2018,46(5):528-539
ABSTRACTThe United Nations’ (UN) sustainable development goals (SDGs), the core of the 2030 Agenda for Sustainable Development and the UN Paris Agreement, were adopted in 2015. Involvement of not only national governments but also all other stakeholders including local governments is important to promote sustainable development and to achieve the goals. The question arises, therefore, of what methods should be used to best implement and assess sustainability issues at a local level. In this light, a new version of Comprehensive Assessment System for Built Environment Efficiency (CASBEE), CASBEE for Cities, is introduced for assessing the sustainability of cities and communities around the world based on SDG indicators and greenhouse gas (GHG) emissions. The tool allows users to understand the sustainability of cities and communities based on quality (Q) and environmental load (L) perspectives. The sustainability assessments show that cities in developed countries tend to have good grades for Q, but bad grades for L, while cities in developing countries tend to have the opposite trend. This will assist cities and communities in both developed and developing countries to understand urgent problems and to identify effective solutions for sustainable development. 相似文献
782.
防屈曲支撑的研究进展及其工程应用 总被引:3,自引:0,他引:3
简要介绍了防屈曲支撑的组成及工作机理,详细介绍了防屈曲支撑的发展和近年来中国学者在理论研究和类型创新方面取得的研究成果;着重讨论了三重钢管、端部铰式、中部接触环式等新型防屈曲支撑的性能;最后给出了防屈曲支撑在中国的应用情况.研究结果表明:防屈曲支撑以其良好的耗能性能会有很好的发展潜力;防屈曲支撑应该向着低屈服点设计、适用于大跨结构、便于安装等方向发展,并在实际工程中推广应用. 相似文献
783.
H. Shirai S. Oshita Y. Makino J. Sugiyama M. Yoshimura 《Food and Bioprocess Technology》2014,7(12):3455-3465
To develop a rapid and nondestructive hygiene-monitoring system in meat-processing plants, plate count and ATP content on pork meat surfaces were quantitatively determined with particular attention to NAD(P)H fluorescence produced by microorganisms. An excitation (Ex)–emission (Em) matrix (EEM) was obtained, and the five fluorescence peaks of tryptophan, NAD(P)H, zinc protoporphyrin IX, protoporphyrin IX, and riboflavin were observed. Plate count and ATP content were predicted with good accuracy [r p?=?0.90–0.94 and root mean square error of prediction (RMSEP)?=?log10 (0.68–0.79 CFU cm?2) for plate count and r p?=?0.84–0.89 and RMSEP?=?log10 (0.61–0.71, mol cm?2) for ATP content]. Two-dimensional Savitzky–Golay second-order differentiation was found to be a powerful preprocessing tool of EEMs to improve prediction accuracy. Better prediction accuracy was obtained when the sensitivity of the fluorescence spectrophotometer was set to focus on fluorescence from NAD(P)H than that from both tryptophan and NAD(P)H. However, little linear relationship was observed between plate count and fluorescence intensity from NAD(P)H (R 2?=?0.31). The absolute value of regression coefficient (RC) of partial least-squares regression (PLSR) at the wavelength assigned to NAD(P)H, zinc protoporphyrin IX, protoporphyrin IX, and riboflavin was high. It can be concluded that a good prediction model was developed in which four fluorescence compounds of NAD(P)H, zinc protoporphyrin IX, protoporphyrin IX, and riboflavin contribute to the prediction model, and these compounds are probably produced by microorganisms. 相似文献
784.
To determine the effects of a vegetarian diet with avocado as a source of monounsaturated fat on serum lipids, thirteen patients with phenotype II (twelve with IIa and one with IIb) dyslipidemia were included in a prospective, transversal and comparative study in which three four-week diets randomly assigned were assessed. One vegetarian diet (ALVD) was composed of 70% carbohydrates, 10% proteins and 20% lipids. Another was composed of 60% carbohydrates, 10% proteins and 30% lipids, 75% of which was supplied by avocado (AVD). A third diet was an avocado-added free diet (FDWA). Body weight, body mass index (BMI), and serum lipids (total cholesterol (TC), high (HDL) and low density lipoprotein (LDL) cholesterol and triglycerides (TG)) were evaluated. AVD produced a significant decrease in LDL. ALVD did not change TC and LDL, while FDWA increased them slightly. The three diets reduced TG levels, but only ALVD did so significantly. All three diets reduced HDL levels, particularly ALVD, which produced the greatest reduction. Low-fat, carbohydrate-rich vegetarian diets may be harmful to hypercholesterolemic patients. The avocado addition to a vegetarian diet does not correct these undesirable effects. To obtain beneficial effects on lipid profile with avocado, lower amounts of carbohydrates and polyunsaturated fatty acids are probably needed. 相似文献
785.
应用三维热工水力程序AQUA对冷热流体混合时发生的热现象进行了数值分析,并用简化基本议程归一化方法对影响该热现象流动参数分布的因素进行了讨论。结果表明,流场与温度场计算结果与归一化分析相符,温度波动计算结果与自然规律一致。这表明AQUA程序能较好地模拟冷热流体混合时发生的热现象。 相似文献
786.
近50年来,天然气的消耗量大大增加,并且会继续增加以降低主要能源的CO2排放量。随着天然气供应量的增加,为保证其输送的经济性和安全性,开发了高强度大直径焊管,并已成功应用在全球多个地区(如北极地区、地震带和深海海域)。天然气需求的增加对长距离输送管线用钢管提出了新的要求,为此,研究了更为恶劣环境下承受高压和轴向应变的高性能钢管;分析了所开发的高压输气管线用高品质钢管的性能;探讨了承受轴向应变钢管的进一步开发。 相似文献
787.
A new method is described in which the dc motor may regenerate power effectively to ac supply. The principle is similar to that with a dc chopper for regeneration of the power from dc motor to dc supply. In this new method, however, thyristor switches synchronizing to the ac supply are used instead of a dc chopper. The principle and the power calculations as well as experimental results are presented. From theoretical and experimental considerations it is clarified that there exist suitable trigger angles in the thyristor of the synchronizing switches. 相似文献
788.
Satoshi Abo Naoyuki MasudaFujio Wakaya Shinobu OnodaTakahiro Makino Toshio HiraoTakeshi Ohshima Toshiaki IwamatsuHidekazu Oda Mikio Takai 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2011,269(20):2360-2363
Soft errors induced by proton, helium and oxygen ion irradiations were measured as a function of distance between a body electrode under partial trench isolation and a metal pad connected to a tungsten via for the first metal layer of a silicon-on-insulator (SOI) static random access memory. Abnormal drain charges induced by ion irradiations with various distances in the SOI metal oxide semiconductor field effect transistor were simulated to be compared with the experimental results. The soft errors were found to depend on the distance between the body electrode and the metal pad in the case of the abnormal drain charge, which is induced by incident ions, lower than the critical charge of the SRAM cells. The soft errors did not depend on the distance for the abnormal drain charges higher than the critical charge. 相似文献
789.
The atmospheric levels of 12 chlorinated polycyclic aromatic hydrocarbons (ClPAHs) associated with particulates at an urban site in Japan were investigated. Only 7 of the 12 species studied were detected in air samples collected monthly during 2002. 1-Chloropyrene (1-ClPy) was detected at the highest concentration (7.5 pg m(-3) (annual mean)), followed by 6-chlorobenzo[a]pyrene (6-ClBaP; 5.6 pg m(-3)) and 9,10-dichlorophenanthrene (5.1 pg m(-3)). The concentrations of the ClPAHs tended to be higher in winter than in summer, with the exception of the 6-ClBaP concentration, which was high in both summer and winter. Correlation analysis also indicated that the behavior of 6-CIBaP differed significantly from that of the other ClPAHs. Comparison of the atmospheric ClPAH concentration profile normalized to 1-CIPy concentration with that for a traffic air sample revealed significant differences between the profiles. The behavior of the atmospheric ClPAHs was also influenced by the origin of the associated particulates, which varied according to season. The positions of chlorination in the detected ClPAHs were consistent with those where the frontier electron density was high. This means that the atmospheric ClPAHs were formed by secondary reactions with chlorine atoms. The photostabilities of the ClPAHs were also investigated in laboratory experiments using a chemical model system. The ClPAHs decayed according to first-order reaction rate kinetics, with photostabilities increasing in the order 6-ClBaP < 1-ClPy < 7-ClBaA < ClPhe < ClFluor, consistent with the trend for the parent PAHs. The photolyses of chlorophenanthrenes and 7-chlorobenz[a]anthracene were confirmed to proceed by initial abstraction of chlorine, followed by oxidative degradation. 相似文献
790.
EE Schmidt T Ohbayashi Y Makino T Tamura U Schibler 《Canadian Metallurgical Quarterly》1997,272(8):5326-5334
The gene encoding the TATA-binding protein, TBP, is highly overexpressed during the haploid stages of spermatogenesis in rodents. RNase protection analyses for mRNAs containing the previously identified first, second, and eighth exons suggested that most TBP mRNAs in testis did not initiate at the first exon used in somatic cells (here designated exon 1C). Using a sensitive ligation-mediated cDNA amplification method, 5' end variants of TBP mRNA were identified, and the corresponding cDNAs were cloned from liver and testis. In liver, a single promoter/first exon is used to generate a steady-state level of roughly five molecules of TBP mRNA per diploid cell equivalent. In testis, we detect modest up-regulation of the somatic promoter and recruitment of at least five other promoters. Three of the alternative promoter/first exons, including 1C and two of the testis-specific promoter/first exons, 1D and 1E, contribute roughly equivalent amounts of mRNA which, in sum, account for greater than 90% of all TBP mRNA in testis. As a result, round spermatids contain an estimated 1000 TBP mRNA molecules per haploid cell. Testis TBP mRNA also exhibits several low abundance 5' end splicing variants; however, all detected TBP mRNA leader sequences splice onto the common exon 2 and are expected to initiate translation at the same site within exon 2. The precise locations of the three major initiation exons are mapped on the gene. The identification of the strong testis-specific promoter/first exons will be important for understanding spermatid-specific tbp gene regulation. 相似文献