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排序方式: 共有454条查询结果,搜索用时 31 毫秒
71.
72.
In this paper,the city prosperity manifest is analyzed through a logical process and a framework is then proposed for designing healthy buildings in Tehran. The current status of urbanization in terms of the number of people living together and the changes in old behavior and perspectives have resulted in deficiencies to the health and hygiene of buildings apart from their surrounding environment. Consequently,these problems have affected people's well-being.This study mainly aims to determine policies and strategies for the architecturaldesign of healthy buildings according to health and safety conditions that influence the quality of internal spaces and external environment of cities.The study is conducted based on logical reasoning and uses focus group and in-depth interviews to assess the final result. The result is aframework that suggests a number of policies that can promote the mental and physical health as well as hygiene of residents through healthy buildings. 相似文献
73.
Mohammadreza Hosseinpour Maryam Asadi Tahmineh Rahmani Eliato Manouchehr Vossoughi Iran Alemzadeh 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2016,38(8):1096-1102
Ethylene glycol is an environmental pollutant, which exists in airport runoff and industrial waste. In this article, biodegradation of ethylene glycol in a two-chamber, batch-mode microbial fuel cell was investigated. Glucose and ethylene glycol at different concentrations were used as carbon and energy sources. Chemical oxygen demand removal in the range of 92–98% indicated that microbial fuel cell can be used for biodegradation of ethylene glycol. Ethylene glycol also improved power generation and the maximum power density was 5.72 mW/m2 (137.32 mW/m3), with respect to the same glucose and ethylene glycol concentrations (500 ppm). 相似文献
74.
To isolate membrane-associated proteins, which play diverse structural, catalytic, and regulatory roles in cells, they are often initially solubilized in detergents. Although detergents are essential for purifying membrane proteins, they tend to interfere strongly with subsequent analyses. A microfluidic method is presented here that surmounts this problem, allowing well-resolved mass spectra of test membrane-associated polypeptides, and their complexes with ions and detergents, to be acquired. As a front-end module it allows access to other advanced mass spectrometric strategies to be utilized toward defining biomolecular interactions. This opens up a new avenue for studying complexation and analysis of membrane proteins of general importance. 相似文献
75.
Maryam Soorgi Mohebbat Mohebbi Seyed Mahmoud Mousavi Fakhri Shahidi 《Food and Bioprocess Technology》2012,5(5):1521-1530
The aim of this study was to determine the effect of microwave pretreatment, usage of methylcellulose, oil temperature, and frying time on mass transfer during deep fat frying of chicken nuggets. Methylcellulose was used in batter and as a coating on product. Microwave with two power densities namely 3.7 and 7.4 W/g was used for reduction of initial moisture content of samples before frying. Frying was performed at three temperatures (150 °C, 170 °C, and 190 °C) and five intervals (0.5, 1, 2, 3, and 4 min) in the sunflower oil. The least oil content was observed when MC was used as a coating layer on non-precooked samples fried at 190 °C. Oil absorption of samples with MC in batter was partially higher compared to control samples. This could be attributed to the rheology of batters. The first-order kinetic model was fitted to moisture and oil content. For determining the correlation between temperature and moisture diffusivity, Arrhenius equation was used. The constant rate for moisture and oil transfer was in the range of 2.2–5 and 0.023–2.67 s?1, respectively. Effective moisture diffusivity values were between 1.43?×?10?8 and 3.24?×?10?8 m2/s. Activation energy ranged between 0.71 and 1.71 kJ/mol. 相似文献
76.
77.
Mohammadreza Nabavitabatabayi Ebrahim ShiraniMohammad Hassan Rahimian 《International Communications in Heat and Mass Transfer》2011,38(1):128-138
This work investigates the heat transfer performance in an enclosure including nanofluids with a localized heat source. The velocity field is solved by multiple relaxation time lattice Boltzmann modeling (MRT) which has superior numerical advantages to single relaxation time lattice Boltzmann modeling (SRT); however, heat transfer is simulated separately using SRT-lattice Boltzmann modeling. The hydrodynamics and thermal fields are then coupled together using the Boussinesq approximation. The main objective of this study is to investigate the influence of several pertinent parameters such as Rayleigh number, solid particle volume fraction of nanoparticles, and the geometry as well as location of the localized heat source on the heat transfer performance of nanofluids. The results obtained from lattice Boltzmann modeling clearly indicate that heat transfer augmentation is possible using nano-fluids in comparison to conventional fluids, resulting in the compactness of many industrial devices. 相似文献
78.
Abbas Mohammadi Mohammadreza Omidkhah Ramin Karimzadeh Ali Haghtalab 《Korean Journal of Chemical Engineering》2013,30(2):465-473
Two procedures have been developed for structural modeling of petroleum fractions based on mixture viscosity and Watson K factor. The representative molecules of paraffinic, naphthenic and aromatic hydrocarbons, based upon Ruzicka’s structural model, have been determined for lube-oil cut SAE 10 from Tehran oil refinery. Unlike previous methods, the newly developed procedures do not require time-consuming and costly laboratory data such as true boiling point profile. Good agreement between predictions of the new models and experimental results has been observed. Moreover, the proposed methods take less run-time than previous models due to less experimental and computational complexities. The results indicate that Ruzicka’s procedure, based on vapor pressure, is only applicable for light hydrocarbon mixtures, while the new methods can be applied for structural modeling of a wide range of petroleum fractions. Furthermore, as a result of this study, the application of a vapor pressure constraint leads to a higher degree of accuracy than the earlier suggested constraint, partial pressure, by Ruzicka. 相似文献
79.
In current research, fractal theory has been applied for estimation of shrinkage of osmotically dehydrated and air-dried kiwifruit using a combination of neural network and genetic algorithm. Kiwifruits were dehydrated at different conditions and digital images of final dried products were taken. Kiwifruit-background interface lines were detected using a threshold combined with an edge detection approach and their corresponding fractal dimensions were calculated based on a box counting method. A neural network was constructed using fractal dimension and moisture content as inputs to predict shrinkage of dried kiwifruit and a genetic algorithm was applied for optimization of the neural network's parameters. The results indicated good accuracy of optimal model (correlation coefficient of 0.95) and high potential application of fractal theory and described intelligent model for shrinkage estimation of dried kiwifruit. 相似文献
80.
Xueping Li Sirisha Nukala Shima Mohebbi 《The International Journal of Advanced Manufacturing Technology》2013,68(1-4):375-389
This paper examines the influence of competition among supply chain partners on product demand. A power law demand function that depends on product pricing and shelf-space allocation (SSA) is used. The exponents in the power law are given by the elasticities of demand. In order to achieve the optimal pricing and SSA strategies in the presence of competition, game-theory-based methodologies—Cournot and Stackelberg games—are employed. For each type of game, a Nash equilibrium is achieved by optimizing the profit as a function of demand and price. A case study is presented to demonstrate the potential of this methodology. The results of this study indicate (1) how to achieve optimal pricing and SSA strategies, (2) how manufacturers can influence demand for a product, (3) that both prices and profits decrease using the Stackelberg game as compared with the Cournot game, and (4) that coordination beyond simple knowledge of price would be beneficial for improving overall profits. 相似文献