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排序方式: 共有520条查询结果,搜索用时 15 毫秒
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To improve the energy efficiency of buildings via compliance to regulation in Iran, Code No. 19 was devised in 1991. The code lacks high level aims and objectives, addressing the characteristics of Iranian buildings. As a consequence, the code has been revised and is not completely implemented in practice, and still remains inefficient. As with any energy coding system, this code has to identify the right balance between the different energy variables for the Iranian climate and way of life. In order to assist improvements to high level objectives of Code 19, this code is compared with ISO 9164, EN 832, German regulation, TS 825 of Turkey and China’s GB 50189 to understand how these have adapted international standards to national features. In order to test the appropriateness of Code 19, five case study buildings in Iran are assessed against Code 19 as well as Turkish standard TS 825 and the results are compared. The results demonstrate that Code 19 is efficient in calculations of building envelope, but it needs improvements in the areas of ventilation, gains from internal and solar sources. The paper concludes by offering suggestions for improving the code. 相似文献
64.
Quantitative structure-activity relationships (QSARs) have proved increasingly useful for predicting the biological activities of molecules (e.g., their binding affinities to different receptors) and can be used in environmental chemistry as a preliminary tool for screening the activities of untested molecules, producing valuable information on which compounds should be tested more thoroughly with experimental affinity assays or in animals. The predictive ability of the consensus kNN QSAR method is corroborated here using a diverse set of 245 compounds, which have been assayed for their relative binding affinities to the estrogen receptor of four species: human (ER alpha and ER beta), calf, mouse, and rat. Leave-one-out cross-validation (LOO-CV) and gamma-randomization tests were applied to the QSAR models for internal validation, and separate training and test sets were used for external validation. The internal predictive abilities of the consensus models for all five data sets were convincing, with cross-validated correlation coefficients (LOO-CV q2 values) varying from 0.69 (human ER beta data) to 0.79 (human ER alpha data). The external predictive abilities were also encouraging, as the predictive r2 scores (pr-r2 values) varied from 0.62 (human ER beta data) to 0.77 (calf and mouse data). The results indicate that consensus kNN QSAR is a feasible method for rapid screening of the estrogenic activity of organic compounds. 相似文献
65.
Hui Wang Yujun Jiang Yashuo Zhang Ziwei Zhang Xinyan Yang Md. Aslam Ali Edward M. Fox Kari S. Gobius Chaoxin Man 《Journal of dairy science》2018,101(12):10775-10791
Silver nanoparticles (AgNP) have been widely applied because of their broad spectrum of antimicrobial activities against bacteria, fungi, and viruses. However, little research has been done to evaluate their effects on Cronobacter sakazakii, an opportunistic pathogen usually infecting infants and having a high fatality rate. The aims of this work were to investigate the antibacterial property of novel, synthesized, positively charged silver nanoparticles against C. sakazakii and to discuss the potential antibacterial mechanisms involved. In this study, the spherical and face-centered cubic silver nanoparticles had a mean particle size of 31.2 nm and were synthesized by reducing Ag+ using citrate and dispersed by glycerol and polyvinylpyrrolidone (PVP) under alkaline conditions. Minimum inhibitory concentrations (MIC) and inhibition zone tests showed that the AgNP exhibited strong antibacterial activity against 4 tested C. sakazakii strains with mean MIC of 62.5 to 125 mg/L and average inhibition zone diameters of 13.8 to 16.3 mm. Silver nanoparticles caused cell membrane injury accompanied by adsorption of AgNP onto the cell surface, as shown by changes in cell morphology, cell membrane hyperpolarization, and accelerated leakage of intracellular reducing sugars and proteins outward from the cytoplasm. In addition, dysfunction of the respiratory chain was induced after treatment with AgNP, which was supported by a decrease in intracellular ATP and inhibition of related dehydrogenases. This research indicates that AgNP could be a novel and efficient antibacterial agent to control C. sakazakii contamination in environments producing powdered infant formulas from milk. 相似文献
66.
重点介绍了美卓造纸机械公司研发的Val-Former靴刮刀叠网成形技术、OptiFormer夹网成形器和OptiFlo Ⅱ型流浆箱,以便为使用较高比例的混合废纸且在更高的车速下生产更低定量瓦楞原纸以及挂面纸板时,获得高效、低能耗和理想质量的产品. 相似文献
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Christoph Stiller Ulrich Bünger Steffen Møller-Holst Ann Mari Svensson Kari A. Espegren Matthias Nowak 《International Journal of Hydrogen Energy》2010
Hydrogen is expected to become an integral part of the Norwegian energy system in the future, primarily as transportation fuel. The NorWays project aims at providing decision support for introduction of hydrogen in the Norwegian energy system by modelling of energy system and hydrogen infrastructure at various spatial levels. GIS-based regional hydrogen demand scenarios and fuelling station networks have been generated, considering organic growth of regional hydrogen coverage and increasing density of hydrogen users over time. A regional model optimised supply scenarios for these fuelling station networks, including choice of production technology (biomass gasification, NG SMR, electrolysis, by-product hydrogen) and delivery (pipeline, truck, and onsite schemes), including integrated hydrogen delivery networks by truck and pipeline. The impact of energy price and GHG emission constraint scenarios on hydrogen production and delivery mix and average hydrogen costs is analysed, and conclusions on the effectiveness of policy measures are drawn. 相似文献
69.
Virginie Treyvaud Amiguet Kari L. Kramp JinQin Mao Calum McRae Andrew Goulah Linda E. Kimpe Jules M. Blais John T. Arnason 《Food chemistry》2012
This study investigated the potential of Northern shrimp (Pandelus borealis Kreyer) by-products as a source of omega-3 polyunsaturated fatty acids (ω-3 PUFAs). The by-products (heads, shell and tail) of processing accounted for approximately 50–60% of the catch. Supercritical CO2 extraction (SFE) of the by-products at 35 MPa and 40 °C generated a deep red oil, rich in ω-3 PUFAs, specifically 7.8 ± 0.06% eicosapentaenoic acid (EPA) and 8.0 ± 0.07 % docosahexaenoic acid (DHA). 相似文献
70.
Lind T Hokkinen J Jokiniemi JK Hillamo R Makkonen U Raukola A Rintanen J Saviharju K 《Environmental science & technology》2006,40(2):584-589
Fine particle emissions from combustion sources have gained attention recently due to their adverse effects on human health. The emission depends on the combustion process, fuel, and particulate removal technology. Particle concentrations at Kraft recovery boiler exits are very high, and the boilers are typically equipped with electrostatic precipitators (ESP). However, little data are available on the ESP performance in recovery boilers. Particle concentrations and size distributions were determined at two modern, operating recovery boilers. In addition, we determined the fractional collection efficiency of the ESPs by simultaneous measurements at the ESP inlet and outlet and the particulate emissions of trace metals. The particle mass concentration atthe ESP inlet was 11-24 g/Nm3 at the two boilers. Particle emissions were 30-40 mg/ Nm3 at boiler A and 12-15 mg/Nm3 at boiler B. The particle size distributions had a major particle mode at around 1 microm. These fume particles contained most of the particle mass. The main components in the particles were sodium and sulfate with minor amounts of chloride, potassium, and presumably some carbonate. The ESP collection efficiency was 99.6-99.8% at boiler A and 99.9% at boiler B. The particle penetration through the ESP was below 0.6% in the entire fume particle size range of 0.3-3 microm. Trace element emissions from both boilers were well below the limit values set by EU directive for waste incineration. 相似文献