共查询到17条相似文献,搜索用时 156 毫秒
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对催化体系进行全局结构优化,搜寻基态结构对预测催化剂结构、分析反应物的吸附特性、研究多相催化反应机理、构建实际反应路径等方面至关重要。遗传算法通过交叉、变异和选择等操作,模拟了自然淘汰进化过程,来搜索势能面上的基态结构。作为一种无偏优化算法,遗传算法的优化过程不依赖于输入结构,具有很强的全局搜索能力。对遗传算法在催化体系的全局结构优化问题中的应用进行了综述,介绍了遗传算法在实空间上进行全局结构优化的基本程序框架以及近年来结合并行计算、机器学习等技术发展的改进框架,并讨论了它们在团簇优化、负载型催化剂的结构优化问题上的相关应用,为遗传算法的进一步改进以及更广泛的应用提供理论指导。 相似文献
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概述了组合催化的基本原理及实验装置,主要介绍了组合催化在丙烯环氧化制环氧丙烷、甲醇与甲苯侧链烷基化制苯乙烯、丁二烯制四氢呋喃、乙烷/丙烷氧化脱氢制乙烯/丙烯等石油化工过程催化剂研发中的应用,指出组合催化将是未来发现新催化材料及新催化过程的有效手段。 相似文献
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An evolutionary approach in the combinatorial selection and optimization of catalytic materials 总被引:1,自引:0,他引:1
A methodical basis of the evolutionary method for selection and optimization of heterogeneous catalytic materials was developed. For validation, the oxidative dehydrogenation of propane was used as a model reaction. Various oxides (V2O5, MoO3, MnO2, Fe2O3, GaO, MgO, B2O3, La2O3) were chosen as primary components for the generation of catalytic materials. The first generation consisting of 56 catalytic materials was created by combination of the primary components in a stochastic manner. The materials of each preceding generation were selected based on the catalytic results obtained and subjected to an evolutionary procedure applying mutation and crossover operators to create further generations of catalytic materials of different qualitative and quantitative compositions. For illustration, four generations were created with a total number of tested catalytic materials of 224. As a result of the preliminary optimization procedure an increase in the propene yield was achieved with increasing number of generations; the results can be certainly improved by screening further generations of catalytic materials. Under standard conditions used for testing (T=500°C, C3H8/O2=3, p(C3H8)=30 Pa), the highest C3H6 yield amounted to 9.0% (S=57.4%) in the 3rd generation on V0.22Mg0.47Mo0.11Ga0.20Ox. 相似文献
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在工程结构的优化设计中,应用遗传算法的基本原理,研究了离散设计变量全局寻优等传统优化方法难于解决的特殊问题。以平面桁架梁作为解析例,选取桁架的节点坐标和杆件的截面特征为设计参数,模拟遗传操作过程中的生物进化机制,对桁架的构成和形状的优化问题进行了解析。得到桁架在不同情况下的形状优化解,并使桁架质量趋于最小。研究结果验证了遗传算法在桁架的形状最优化和最小质量设计中应用的可行性。 相似文献
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Mass exchange network synthesis using genetic algorithms 总被引:4,自引:0,他引:4
Mass Exchange Networks (MENs) are used in the chemical industry to reduce the waste generated by a plant to an acceptable level at the cheapest cost. Finding the optimal network, however, is often difficult due to the non-convexity of the mathematical representation of the problem. This paper describes a novel approach for the synthesis of MENs and MENs with regeneration using Genetic Algorithms (GA), a stochastic optimisation technique based on the concepts of natural evolution. We present an encoding for a genetic algorithm which describes a rich search space, considering both stream splitting and in-series exchangers. For a certain class of problems, all encoded solutions are feasible and require a simple evaluation to yield a cost, resulting in an efficient genetic algorithm. For other problems, the number of infeasible solutions is small, having little effect on the convergence of the genetic algorithm. In comparison with other methods, the GA presented herein is able to find better networks than have been reported elsewhere. 相似文献
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O. V. Buyevskaya A. Brückner E. V. Kondratenko D. Wolf M. Baerns 《Catalysis Today》2001,67(4):369-378
An evolutionary approach was applied to create five generations of -Al2O3-supported multi-metal-oxides to be used as catalytic materials for the oxidative dehydrogenation of propane at 773 K. Each generation consisted of 56 differently composed materials, i.e., a total amount of 280 materials. These catalytic materials were tested in parallel. For the best materials propene yields from 7% (1st generation) to 9% (5th generation) were achieved. Some of these superior catalysts were characterised by XRD, XPS and EPR. A correlation between catalytic performance and the Mg/V ratio on the surface was found. Based on the structural knowledge obtained, from which the requirement of isolated or at least weakly interacting vanadium sites was derived, VOx (2.8 wt.%)/MCM-48 and VOx (2.8 wt.%)/MCM-41 catalysts with a high dispersion of vanadia were used as reference giving a maximal propene yield of 17 and 15%, respectively. 相似文献