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101.
热工综合实验台计算机测控系统的设计 总被引:3,自引:0,他引:3
介绍了热工综合实验台计算机测控系统的硬件结构和软件功能,重点阐述了数据采集与通讯、仪表与控制界面、实时数据曲线绘制等软件设计问题。测控软件以VB6.0为平台,引入Measurement Studio软件所提供的ActiveX虚拟仪器控件和Flash动画界面,构成了具有Windows操作风格、虚拟仪器测控界面和工艺流程动画显示为一体的计算机测控软件。 相似文献
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项新耀 《华北电力大学学报(自然科学版)》2004,31(6)
在查阅、分析近 50 多年出版的热力学著作中有关 与 传递内容的基础上,探讨了 理论发展过程的阶段划分, 概念、理论的演变规律,目前 研究的动态和可能形成的新研究热点。 相似文献
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The proposed work investigates optimal values of various decision variables that simultaneously optimize power output, overall thermal efficiency and thermo-economic function of solar driven Stirling heat engine with regenerative heat losses, conducting thermal bridging losses using evolutionary algorithm based on second version of non-dominated sorting genetic algorithm (NSGA-II) in matrix laboratory (MATLAB) simulink environment. Effects of design parameters as absorber temperature, concentrating ratio, radiative and convective heat transfers are considered for the investigation. Pareto frontier is obtained for triple and dual objectives and the best optimal value is selected through four different decision making techniques viz. Fuzzy Bellman-Zadeh, Shannon’s entropy, LINMAP and TOPSIS. The optimum values of average absorber temperature and concentrating ratio are found to be 1168 K and 1300, respectively. Triple objective evolutionary approach applied to the proposed model gives power output, overall thermal efficiency and thermo-economic function as (38.96 kW, 0.2392, 0.3124) which are 17.09%, 35.09% and 10.74%, respectively lower in comparison with reversible system. With the objective of error investigation, the average and maximum error of the obtained results are reckoned at last. 相似文献
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Runqiang Yu Bining Xue Jiaqi Liao Wanting Zhu Jiayuan Fu 《Fullerenes, Nanotubes and Carbon Nanostructures》2021,29(1):28-38
AbstractIn the present study, lanthanum modified carbon nanotubes (La-CNTs) were prepared by the impregnation method and used as adsorbents to remove oxytetracycline (OTC) from aquaculture wastewater. La-CNTs were characterized by SEM, EDS, XRD, BET analysis. The effects of adsorbent dosage, concentration of OTC, adsorption time, pH and interfering ions on the adsorption of OTC by La-CNTs were investigated. The optimum adsorbent dosage, OTC concentration, adsorption equilibrium time and pH for OTC adsorption by La-CNTs are 0.03?g, 20?mg/L, 180?min and 7, respectively. The outcome of the kinetics studies showed a significant linear correlation between the experimental results and the quasi-second-order kinetics model. As an adsorption isotherm model, the Langmuir model showed a very good consistency with the adsorption of OTC by La-CNTs, as the maximum adsorption quantity reached 117.23?mg/g. Through the thermodynamic analysis showed that the adsorption of OTC by La-CNTs was an endothermic process of entropy increase, which occurs spontaneously. The predominant forces promoting this adsorption were van der Waals force, π-π electron donor-acceptor interaction, and electrostatic interaction. 相似文献
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Changling Zhuang Jianhua Liu Zhenli Mi Haitao Jiang Di Tang Guoxuan Wang 《国际钢铁研究》2014,85(10):1432-1439
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The sequencing of the human genome raises two intriguing questions: why has the prediction of the inheritance of common diseases from the presence of abnormal alleles proved so unrewarding in most cases and how can some 25 000 genes generate such a rich complexity evident in the human phenotype? It is proposed that light can be shed on these questions by viewing evolution and organisms as natural processes contingent on the second law of thermodynamics, equivalent to the principle of least action in its original form. Consequently, natural selection acts on variation in any mechanism that consumes energy from the environment rather than on genetic variation. According to this tenet cellular phenotype, represented by a minimum free energy attractor state comprising active gene products, has a causal role in giving rise, by a self-similar process of cell-to-cell interaction, to morphology and functionality in organisms, which, in turn, by a self-similar process entailing Darwin''s proportional numbers are influencing their ecosystems. Thus, genes are merely a means of specifying polypeptides: those that serve free energy consumption in a given surroundings contribute to cellular phenotype as determined by the phenotype. In such natural processes, everything depends on everything else, and phenotypes are emergent properties of their systems. 相似文献
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