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991.
针对如何保证室内粉刷石膏的施工质量进行了探讨,分别从原料、基层处理、操作工艺、成品保护四方面进行了介绍,以指导实践,保证室内粉刷石膏施工符合要求,为后续装修提供保障。 相似文献
992.
In this study, the gas turbine power plant with preheater is modeled and the simulation results are compared with one of the gas turbine power plants in Iran namely Yazd Gas Turbine. Moreover, multiobjective optimization has been performed to find the best design variables. The design parameters of the present study are selected as: air compressor pressure ratio (rAC), compressor isentropic efficiency (ηAC), gas turbine isentropic efficiency (ηGT), combustion chamber inlet temperature (T3) and gas turbine inlet temperature. In the optimization approach, the exergetic, economic and environmental aspects have been considered. In multiobjective optimization, the three objective functions, including the gas turbine exergy efficiency, total cost rate of the system production including cost rate of environmental impact and CO2 emission, have been considered. The thermoenvironomic objective function is minimized while power plant exergy efficiency is maximized using a genetic algorithm. To have a good insight into this study, a sensitivity analysis of the results to the interest rate as well as fuel cost has been performed. In addition, the results showed that at the lower exergetic efficiency in which the weight of thermoenvironomic objective is higher, the sensitivity of the optimal solutions to the fuel cost is much higher than the location of Pareto Frontier with the lower weight of thermoenvironomic objective. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
993.
In the early stage of a design process, it is important to create numerous and varied possible color plans for the target consumer group. These color plans help individual designers quickly find a few good color design schemes and give the design team ideas for brainstorming. The color plan of a product consists of the color combinations of its components and decorative patterns, which strongly influence the feelings of customers and thus their desire to purchase. However, very few studies have discussed these issues. In this study, a consultation and simulation system for product color planning that helps designers obtain the optimal color planning for components and decorative patterns of a product is proposed. This system includes two parts: one uses the interactive genetic algorithm to establish a creative evolutionary system that can interact with a designer to explore novel design schemes; the other extends the boundary extract algorithm to establish a color simulation system that can apply colors to the areas of product components and decorative patterns for color simulation. Finally, a case study of color planning for a motorcycle model is used to verify the feasibility of the proposed system. © 2012 Wiley Periodicals, Inc. Col Res Appl, 38, 375–390, 2013 相似文献
994.
In coke production plants one of the most important wastewaters generated comes from the condensates of the gas coke pipelines which contains important quantities of toxic components such as phenols or thiocyanates. These contaminants can be treated by ion exchange. In this work, thiocyanate and phenol has been retained on strong anionic resins: Lewatit MP500 and Lewatit M610. Equilibrium and kinetics were studied and equilibrium constants and diffusivity values determined using different models. Breakthrough curves from the load and elution steps were carried out in order to evaluate the ion exchange operation in fixed bed. In the elution step the contaminants could be concentrated four times permitting their treatment. The results allow the determinination of the feasibility of ion exchange operations to diminish the thiocyanate and phenol concentration producing a final wastewater that can be used as treatment in the biological depuration of plants without poisoning the active sludges. 相似文献
995.
996.
Arne Sloth Jensen 《Drying Technology》2013,31(5-7):1377-1393
ABSTRACT Drying in superheated steam under pressure gives possibilities for pollution free drying, energy recovery. reduced drying time and a very compact drying equipment. Products are dried i n a pressurized cellular fluid bed by super heated steam blown through the cells. Above the fluid bed dust is separated before the steam is reheated and recirculated to the cells by a fan. The evaporated water leaves the dryer as usable steam at e.g. 3 bar g, and full energy recovery is obtained. Today 14 plants have been builtor are under construction, with capacities from 2 to 40t / h water evaporation. This technology is suited for drying of beet pulp, residues from starch production of corn or wheat. sludge. spent grain. brown coal. wood chips and bark. The technology shows great options for integration in steam systems in various industries, whereby drying is possible without using primary energy and pollution is avoided. 相似文献
997.
T. Ttayagarajan M. Ponnavaikko J. Shanmugam R.C. Panda PG. Rao 《Drying Technology》2013,31(6):931-966
Abstract This paper reviews the developments in the model based control of drying systems using Artificial Neural Networks (ANNs). Survey of current research works reveals the growing interest in the application of ANN in modeling and control of non-linear, dynamic and time-variant systems. Over 115 articles published in this area are reviewed. All landmark papers are systematically classified in chronological order, in three distinct categories; namely, conventional feedback controllers, model based controllers using conventional methods and model based controllers using ANN for drying process. The principles of ANN are presented in detail. The problems and issues of the drying system and the features of various ANN models are dealt with upto-date. ANN based controllers lead to smoother controller outputs, which would increase actuator life. The paper concludes with suggestions for improving the existing modeling techniques as applied to predicting the performance characteristics of dryers. The hybridization techniques, namely, neural with fuzzy logic and genetic algorithms, presented, provide, directions for pursuing further research for the implementation of appropriate control strategies. The authors opine that the information presented here would be highly beneficial for pursuing research in modeling and control of drying process using ANN 相似文献
998.
Dr. Shixin Ye Morgane Riou Stéphanie Carvalho Dr. Pierre Paoletti 《Chembiochem : a European journal of chemical biology》2013,14(2):230-235
Heterologous expression of ligand‐gated ion channels (LGICs) in Xenopus laevis oocytes combined with site‐directed mutagenesis has been demonstrated to be a powerful approach to study structure–function relationships. In particular, introducing unnatural amino acids (UAAs) has enabled modifications that are not found in natural proteins. However, the current strategy relies on the technically demanding in vitro synthesis of aminoacylated suppressor tRNA. We report here a general method that circumvents this limitation by utilizing orthogonal aminoacyl‐tRNA synthetase (aaRS)/suppressor tRNACUA pairs to genetically encode UAAs in Xenopus oocytes. We show that UAAs inserted in the N‐terminal domain of N‐methyl‐D ‐aspartate receptors (NMDARs) serve as photo‐crosslinkers that lock the receptor in a discrete conformational state in response to UV photo treatment. Our method should be generally applicable to studies of other LGICs in Xenopus oocytes. 相似文献
999.
1000.