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101.
Building envelope impacts upon energy consumption and indoor environment. The relationship between envelope components and indoor environment has become increasingly important, especially with the new emphasis on visual comfort, thermal comfort and indoor air quality. This paper examines the interaction between occupant thermal comfort and envelope component regulations in the Gulf States. The country chosen for this study is the Kingdom of Bahrain, the smallest country in the Gulf region. Simulation results and comparative studies were employed to investigate the impact of the current envelope component regulations on the internal environment. The paper focuses on residential buildings and concludes that the envelope component regulations contribute positively to the internal thermal performance. Although these envelope components are not generally the primary elements that impact upon internal thermal comfort there are circumstances when the components become very warm and occupants positioned close to them will experience discomfort. This paper shows that the thermal insulation regulation makes a small impact on thermal comfort, whereas the window regulation, particularly glazing, is more influential and that for most window areas, solar impacts are generally large. 相似文献
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This article reports on the comparative study of the fabrication of porous anodic alumina films by anodisation of the aluminium films on glass substrates which were deposited by direct current sputtering and electron beam evaporation methods. The relationship between surface morphology of the deposited aluminum films and porous anodic alumina films was investigated. A more uniform and ordered porous anodic alumina was obtained by fabricating from electron beam evaporation deposited aluminium film with smaller and compact grains. Two-step anodisation was used to further improve the quality of porous anodic alumina compared to one-step anodisation. The optical transmittance spectra within wavelength of 370–800 nm were obtained and the optical properties were studied. 相似文献
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Ishtiaq Hassan Abdul Razzaq Ghumman Hashim Nisar Hashmi Abdul Sattar Shakir 《Civil Engineering and Environmental Systems》2013,30(4):365-376
This study has been carried out to forecast the impact of global warming on the precipitation pattern of Saudi Arabia by the end of year 2100. Simulation has been done using EdGCM model software (with available 8×10 resolution) developed at Columbia University on which there have been produced global precipitation maps for the seasonal and annual averages for the last 5 years (2096–2100). For each map, EdGCM grid values surrounding Saudi Arabia are used as input to one of the tools of Eagle point software called surface modelling (SM). SM is a new approach for downscaling global climate model results. SM software modelled out isohyets at 0.2 mm/day interval. The results indicate that the present pattern of precipitation (more in winter and less in summer) is going to change by almost equal occurrence of precipitation in all seasons for double_CO2 (2CO2) experiment. The 2CO2 experiment indicates an increase of about 16.05% over the annual average precipitation across the country. 相似文献
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Urethane‐forming reaction kinetics and catalysis of model palm olein polyols: Quantified impact of primary and secondary hydroxyls 下载免费PDF全文
Tuan Noor Maznee Tuan Ismail Kosheela Devi Poo Palam Zailan Bin Abu Bakar Hoong Seng Soi Yeong Shoot Kian Hazimah Abu Hassan Christi Schiffman Aisa Sendijarevic Vahid Sendijarevic Ibrahim Sendijarevic 《应用聚合物科学杂志》2016,133(5)
Model palm olein natural oil polyols (NOPs) with varying ratios of primary to secondary hydroxyls were synthesized, characterized, and evaluated in reaction kinetics study with isocyanate in formation of polyurethanes. Reaction rate constants and activation energies associated with primary and secondary hydroxyls of NOPs were quantified. The kinetic study in toluene shows that the NOP containing primary hydroxyls have three times higher reaction rate constants in noncatalyzed reaction with 4,4′‐diphenylmethane diisocyanate (4,4′‐MDI) compared to the model NOP containing only secondary hydroxyls, which is associated with higher activation energy of secondary hydroxyls. However, the difference in reaction rate constants of primary and secondary hydroxyls in NOPs diminished in the reactions catalyzed with dibutyltin dilaurate. Bulk polymerization reaction confirms the kinetics results in toluene, showing that the model NOP containing primary hydroxyls reached gel time at a faster rate. Evaluation of elastomers from bulk polymerization shows low degree of phase separation of hard and soft segments for elastomers based on the model NOPs. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 42955. 相似文献
108.
Barkai Hassan El Abed Soumya Sadiki Moulay Iraqui Houssaini Mohammed 《The Journal of Adhesion》2016,92(5):341-348
The sessile drop technique was used to investigate the evolution of the physicochemical properties of cedar wood as a function of contact time with the Penicillium expansum spores. The most important finding showed that the impact of different contact periods (2, 4, 6, 8, 10, and 24 hr) on the wood surface were very indicative. In fact, after 2 hr of contact, the results have shown a significant impact of the bioadhesion of spores to the substrate on both the hydrophobic character (θW = 108.5°; ΔGiwi = ?28.25 mJ/m2), the electron donor (γ? = 13.63 mJ/m2), and the electron acceptor (γ+ = 4.35 mJ/m2) parameters that were significantly reduced compared to the initial wood (θW = 118.5°; ΔGiwi = ?6.29 mJ/m2; γ? = 32.1 mJ/m2; and γ+ = 9.1 mJ/m2). In addition, this decrease of parameters continued over time to stabilize after 10 hr of contact. Indeed, after 24 hr, the acid/base properties were almost zero and the contact angle with water decreased to 30°. Moreover, it was found that the coefficient of correlation (r2) was strong between the contact angle with water, the surface energy, and the electron acceptor character with the contact time parameter with values (r2 = 0.65), (r2 = 0.79), and (r2 = 0.68), respectively. 相似文献
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Musarat Amina Touseef Amna Mallick Shamshi Hassan Nawal Musayeib Al Musayeib Salem Slayyem Salem Al-Deyab Myung-Seob Khil 《Korean Journal of Chemical Engineering》2016,33(11):3169-3174
Pure water is the fundamental requisite for human life. The water has been recycled naturally but not in an adequate amount for consumption. Nanotechnology with extraordinary applications provides competent ways for the decontamination of contaminated water. In the present study MnWO4 nanoflowers endorsed with inherent antibacterial activity were successfully synthesized by facile hydrothermal approach. XRD, SEM, EDX spectroscopy and UVDRS were used to characterize the as-synthesized nanoflowers. Gram negative Escherichia coli ATCC 52922 bacterium was used as model organism to test antibacterial activity of as-synthesized MnWO4 nanoflowers. This study was conducted to optimize minimum concentration of MnWO4 nanoflowers and maximum contact time required to achieve complete inactivation of bacteria present in contaminated water. Minimum inhibitory concentration (MIC) of MnWO4 nanoflowers was found to be 10 μg/ml. The assessment and interpretation of bacterial viability was done using dual fluorescent staining. The synthesized 3D-nanoflowers were found as potent bactericides. Thus, MnWO4 nanoflowers emerged to be very good future material for disinfection of biological pollutants present in the contaminated water reservoirs and as an anti-biofouling agent. 相似文献