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1.
Chemical looping has been proposed as an emerging technology for large-scale hydrogen storage with the advantages of high volumetric hydrogen storage density, environmental compatibility, and safety. However, to ensure sufficient redox activity, conventional oxygen carrier materials must be operated at a temperature higher than 800 °C, leading to the rapid deterioration on the storage capacity over several cycles. In this work, we report a ternary ferrite-spinel material Cu0.5Co0.5Fe2O4 for chemical looping hydrogen storage and production. The material exhibits high volumetric hydrogen storage density (65.58 g·L−1) and average hydrogen production rate (142 μmol·g−1·min−1) at 550 °C. The performance is maintained with negligible deactivation over repetitive redox cycles. The high performance can be attributed to the ability of Cu and Co to improve the reduction and the reversible phase change during the oxidation stage at moderate temperatures. The performance of the Cu0.5Co0.5Fe2O4 is comparable to the state-of-the-art Rh-FeOx containing rare earth metals, which enables its potential in industry application.  相似文献   
2.
This paper introduces a synergic predator-prey optimization (SPPO) algorithm to solve economic load dispatch (ELD) problem for thermal units with practical aspects. The basic PPO model comprises prey and predator as essential components. SPPO uses collaborative decision for movement and direction of prey and maintains diversity in the swarm due to fear factor of predator, which acts as the baffled state of preys’ mind. In the SPPO, the decision making of prey is bifurcated into corroborative and impeded parts. It comprises four behaviors namely inertial, cognitive, collective swarm intelligence, and prey's individual and neighborhood concern of predator. The prey particle memorizes its best and not-best positions as experiences. In this research work, to improve the quality of prey swarm, which influence convergence rate, opposition based initialization is used. To verify robustness of proposed algorithm general benchmark problems and small, medium, and large power generation test power system are simulated. These test systems have non-linear behavior due to multi-fuel options and practical constraints. The constraints of prohibited operating zone and ramp rate limits of power generators’ are handled using heuristics. Newton–Raphson procedure is exploited to attain the transmission losses using load flow analysis. The outcomes of SPPO are compared with the results described in literature and are found satisfactory.  相似文献   
3.
针对多属性决策中多个相互冲突的属性信息使决策者很难做出决策判断的问题,文中从支持直觉模糊集的角度研究该问题.首先,在支持直觉模糊集的基础上,结合多粒度粗糙集理论,构造乐观、悲观两种多粒度支持直觉模糊粗糙集模型,分析两种模型之间的相互关系,讨论相关性质.然后,利用t-模和t-余模定义拟合函数,提出多粒度支持直觉模糊粗糙集的多属性决策求解方法,同时定义得分函数和精确函数排序决策结果,提取相应的决策规则,设计算法.实例分析表明,文中方法使决策者在处理信息冲突的多属性决策问题时可根据实际需求选择最优决策方案  相似文献   
4.
文章讨论了苏丹I-中性配位体协萃体系萃取分离锂同位素中螯合剂和协萃剂的结构效应。为了获得高的同位素分离效应,螯合剂必须是弱酸性的(PK_α>11),具有强的分子内氢键及易于形成六元螯合环。协萃剂结构不仅要求无空间位阻,而且具有强的配位基。α随配位基的碱性增大而相应提高。萃取络合物中螯合环的增多亦有利于体系α的提高。此外本文还讨论了一些萃取体系的同位素富集方向和萃锂体系用于分离同位素的前景。  相似文献   
5.
目前税务部门都建立起了面向事务处理的税收征管信息系统(OLTP系统).但这些系统缺乏对历史数据的有效分析和利用,很难为决策者提供综合的、高效的辅助决策信息,因此提出了采用数据仓库技术和联机分析技术实现税务征管信息化的解决方案.为税务部门决策科学化、理性化提供可靠保障.提升税收工作的计划、决策、执行、监控和管理能力.  相似文献   
6.
咪唑啉型缓蚀剂的合成及其缓蚀机理的研究   总被引:2,自引:0,他引:2  
以棕榈酸、二乙烯三胺、马来酸酐为原料合成了一种咪唑啉型缓蚀剂YQ-01,与YQ-02复配后得到能有效抑制二氧化碳腐蚀的缓蚀体系YQ-03。应用静态挂片失重法、电化学极化曲线、X射线光电子能谱分析研究了YQ-03抑制二氧化碳腐蚀的电化学特征,分析了腐蚀前、后及加入缓蚀体系YQ-03后A3钢的表面产物,探讨了YQ-03的缓蚀机理。结果表明,由主剂YQ-01和助剂YQ-02组成的复配缓蚀体系有良好的协同作用,腐蚀产物膜有3层,能有效抑制饱和CO2的高矿化度盐水对A3钢的腐蚀。  相似文献   
7.
Today, a new role for maintenance exists to enhance the eco-efficiency of the product life cycle. The concept of “life cycle maintenance” emerged to stress this role leading to push, at the manufacturing stage, an innovative culture wherein maintenance activities become of equal importance to actual production activities. This equivalence requires mainly considering the integration of the maintenance and production strategy planning for developing opportunistic maintenance task keeping conjointly the product - production - equipment performances. In this paper, a novel approach is proposed for integrating maintenance and production planning. The approach uses the “odds algorithm” and is based upon the theory of optimal stopping. The objective is to select, among all the production stops already planned, those which will be optimal to develop maintenance tasks keeping the expected product conditions. It combines criteria such as functional performance and component reliability. Approach feasibility is shown on a practical example.  相似文献   
8.
吴进  杜琳  李桂英  胡常伟 《贵金属》2006,27(4):18-25
本文以自制钛基RuOx-PdO电极为阳极,钛片为阴极,NaCl为电解质,研究了活性艳红K-2BP的电催化氧化降解行为.实验结果表明,在pH值为2.0、NaCl浓度为0.02mol/L、电流密度为0.25mA/cm2和室温条件下,20mg/L活性艳红K-2BP经电催化氧化1h,脱色率可以达到99.6%.在本实验条件下,活性艳红K-2BP的脱色降解主要是电生活性氯的间接氧化和钛基RuOx-PdO 电极直接氧化协同作用的结果.作者用钛基RuOx-PdO 电极降解活性艳红K-2BP,其适用性较强,可在较大的温度范围、较宽的染料浓度时达到较好的脱色效果.表明作者自制钛基RuOx-PdO电极具有良好的电催化氧化性能,在降解活性染料方面,有一定的应用前景.  相似文献   
9.
A novel hybrid catalyst system containing alkali formate and Cu/MgO–Na was developed to synthesize methanol from syngas via ethyl formate in a slurry reactor. The results exhibited that high CO conversion (>80%) and methanol selectivity (90%) with a mass space velocity of 1800 L(STP)/(h kg) were achieved at a low temperature of 433 K and at 5.0 MPa. A synergic function between HCOOM (M = Li, Na, K, Rb and Cs) and Cu/MgO–Na was in existence for promoting the reaction performance, in which sodium formate showed the optimizing synergy with Cu/MgO–Na catalyst. In addition, the nature of the solid copper catalysts also had a remarkable influence on the catalytic activity.  相似文献   
10.
现代多媒体交互中心(即协作型CRM系统)的主要设备是CTI中间件,需要实现对电话渠道、E-mail渠道、Web互动渠道的统一管理,并能够根据用户信息和座席技能、工作状态等多种因素,将呼叫进行统一分配和路由,由最适合的座席进行应答和处理。该文论述了一个支持多媒体统一排队的CTI中间件的设计,对软件总体结构进行了设计,并对该软件中实现多媒体统一接入的媒体服务器模块进行了探讨。  相似文献   
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