锑掺杂氧化锡纳米粉体的制备及其研究进展

按照气相法、液相法和固相法的分类,对锑掺杂氧化锡纳米粉体的制备方法进行了综述,概括了各类制备方法的优缺点,并对未来进行了展望.     

多晶硅材料及其生产工艺研究现状与趋势

本文介绍了多晶硅材料,综述了制备改良西门子法、冶金法和流态化工艺制备多晶硅,并对这几种方法进行了比较分析。     

一种有机无机碱性固态电解质膜的制备研究

文章主要研究了一种有机无机杂化复合碱性固态电解质膜的制备方法及导电性能。研究了采用物理共混法和原位合成法制备基于PVA-KOH-H2O(基体)-Mg(OH)2(掺入物)体系的碱性固态电解质膜,同时,还引入离子交换法,浸洗掉电解质膜中的杂质离子,并对其进行了研究探讨。测试表明,随着KOH比例不断升高和H2O含量增加,聚合物膜的电导率逐渐升高;Mg(OH)2的掺入有利于进一步提高复合膜中KOH的含量;原位合成法制备的膜的各种性能均好于物理共混法制备的膜,但离子交换法的引入,会削弱制备的膜的性能。     

单晶硫酸钙纳米管的制备

现主要针对硫酸钙纳米管的研究状况,进一步整理设计出相应的硫酸钙纳米管的制备方法,在此主要针对两种主要制备方法：非片状结构化合物形成纳米管的方法和反相胶束法合成单晶硫酸钙纳米管进行了分析和浅评。     

三水碳酸镁法生产高纯活性氧化镁的探究

本文就三水碳酸镁法生产高纯氧化镁的工艺原理、流程、设备等方面进行阐述,旨在阐述优化工艺对提高生产使用效率的促进作用。通过分析改种方法在不产生三废的前提下,是一种制备工艺合理和产出效率高的制备方法。     

不同方法制备的Ru-Ti-Ir-Ta/Ti四元涂层钛阳极的比较

采用热分解法和Sol-gel法,制备了具有三明治涂层结构的Ru-Ti-Ir-Ta/Ti四元金属氧化物钛阳极.采用XRD和SEM方法分析了涂层的相组织结构特征,通过Tafel曲线和循环伏安曲线的测试研究并比较了涂层的电催化活性.结果表明,两种方法制备的阳极涂层相成分都以 (Ir, Ta)O2和(Ti, Ru)O2金红石固溶体相为主.在热分解法制备的涂层中还存在单质金属钌.采用Sol-gel法制备涂层,其晶粒更为细小.采用热分解法和Sol-gel法制备的钛阳极涂层表面形貌有明显的不同,前者可见明显的"泥裂状"裂纹,后者呈碎石状.采用Sol-gel制备的钛阳极比热分解法制备的钛阳极具有更好的电催化活性和耐蚀性.     

三防纳米涂料的研究与发展

本文主要介绍了三防纳米涂料的设计理念,并简述了三方纳米涂料的构成包括成膜物质、颜填料、溶剂以及助剂;还介绍了三防的纳米涂料相应的配置机理以及制备方法,包括溶胶-凝胶法、共混法、原位聚合法、插层复合法四种;还对三防纳米涂料进行了相应的展望。     

微波辅助与水热法合成形貌可控的Mn_3O_4纳米材料及其电化学性能研究

超级电容器是上世纪兴起的新型储能装置,具有功率大,快速充放电,环境无污染等优点。对超级电容器的电极材料的研究是目前的热点之一。四氧化三锰具储量丰富,成本低廉,绿色环保等优点受到重视。文章用水热法和微波辅助合成法制备得到不同形貌的四氧化三锰纳米材料,采用XRD,IR,SEM等分析手段对其晶型,结构,形貌进行了表征。采用循环伏安法和恒电流充放电法对其电容特性进行了比较,证明水热法制备得到的纳米材料结晶性弱,具有无定型结构,电化学性能优于微波辅助法合成的纳米材料。     

纳米纤维素的概述

概述了纤维素的内部结构单元和物理、化学、力学特性。还简要汇总了主要的制备方法,包括化学法、物理法、生物法等,分析了不同方法的特点,最后,提出了目前围绕纳米纤维素的高效制备、改性合成、推广应用等几个方面开展纳米纤维素的研究。     

镍钴铝酸锂三元正极材料的制备方法

镍钴铝锂电池作为一种三元锂离子电池,因为具有较高的能量密度和循环寿命,而受到了广泛的关注。但是制备工艺却一直是制约镍钴铝酸锂大规模应用的关键因素之一。本文综述了镍钴铝酸锂三元正极材料的5种常见制备方法的优点和缺点,包括固相反应烧结法、共沉淀法、水热法、凝胶溶胶法和喷雾热分解法。分析近几年的研究趋势,得出将两种制备方法相结合,优势互补,是目前的镍钴铝酸锂制备方法的研究趋势,并且进一步采用掺杂和表面包覆,提高材料的导电性、循环性能和倍率性能。     

Combining research and design: a methodological view of the path to sustainable development

This essay sketches a conceptual framework of a method for investigations into sustainable development issues by combining a method for scientific research with a method for designing. These kinds of investigation should not only focus on the development of a new theory explaining what sustainable development is, it also needs to focus on how sustainable development can be realized. Firstly, the two methods are described separately. After a comparison of the methods, the conceptual framework is sketched as a phase model and finally a translation of this conceptual framework into a more practical guideline is given. In practice, the practitioner does not follow a given phase model. The practitioner needs building blocks to build his own pattern. To guide the practitioner in building his own structure, some ‘rules’ or guidelines are needed. © 1998 John Wiley & Sons, Ltd and ERP Environment.     

电力系统短期负荷混沌预测法

电力系统短期负荷预测,在日常工作中具有十分重要的意义,它是保证电力系统的安全、经济运行的基础。文章简要对短期负荷预测的研究方法进行介绍,详细分析了混沌理论预测方法,包括相空间重构等主要思想。另外,选择合适的综合预测模型才是提高预测精度的主要方法。     

海工产品投标报价及成本估算应用浅析

产品报价的基础是成本,报价与成本估算有着密切的关系。文章在对海洋工程装备产品各方面的理论研究基础上,分析海工产品投标报价阶段和建造阶段的实践特点;阐述现有成本估算方法在海工企业的应用现状及存在的问题;综合应用类比法、特征映射以及作业成本法,提出一种基于BOM(Bill of Material,物料清单)的集成成本估算方法,提高企业报价竞争力,指导后续生产实施。     

FFORMA: Feature-based forecast model averaging

We propose an automated method for obtaining weighted forecast combinations using time series features. The proposed approach involves two phases. First, we use a collection of time series to train a meta-model for assigning weights to various possible forecasting methods with the goal of minimizing the average forecasting loss obtained from a weighted forecast combination. The inputs to the meta-model are features that are extracted from each series. Then, in the second phase, we forecast new series using a weighted forecast combination, where the weights are obtained from our previously trained meta-model. Our method outperforms a simple forecast combination, as well as all of the most popular individual methods in the time series forecasting literature. The approach achieved second position in the M4 competition.     

电子商务环境下基于B2C的物流配送路径优化

电子商务环境下的物流配送具有客户位置分散、订单多、批量小和重复线路多的特点,传统的线路优化方法都在不同程度上遇到各种问题。文中针对电子商务环境下的配送特殊性,采用改进两阶段算法混合进行求解。第一阶段用K-means聚类法将客户群分成若干区域,在每个区域又用扫描算法分解成若干符合约束条件的小规模子集;第二个阶段对各个分组内的客户点,就是一个个单独的TSP模型的线路优化问题,采用改进遗传算法进行优化求解。最后,结合具体实例,实验证明了该改进算法的有效性。     

A tale of two correlations: Evidence and theory regarding the phase shift between the price level and output

We examine the relationship between the price level and output at business-cycle frequencies. In the postwar period, there is evidence of a phase shift between the price level and output. Such a phase shift is manifested in the price level being countercyclical and the inflation rate being procyclical or acyclical, depending on the detrending method used. Our examination takes three approaches. First, we apply bootstrapping methods to characterize the two correlations, though the methodology could easily be extended to any set of facts. Second, we specify a model economy with forecast heterogeneity, showing numerically that this model economy can match the observed pair of correlations. Third, we apply robust control theory, deriving conditions in which the price level is countercyclical and the inflation rate is procyclical.     

Stochastic labelling of biological images

Many hypotheses made by experimental researchers can be formulated as a stochastic labelling of a given image. Some stochastic labelling methods for random closed sets are proposed in this paper. Molchanov (I. Molchanov, 1984, Theor. Probability and Math. Statist. 29 , 113–119) provided the probabilistic background for this problem. However, there is a lack of specific labelling models. Ayala and Simó (G. Ayala and A. Simó, 1995, Advances in Applied Probability 27 , 293–305) proposed a method in which, given the whole set of connected components, every component is classified in a certain phase or category in a completely random way. Alternative methods are necessary in case the random labelling hypothesis is not reliable. A different kind of labelling method is proposed that considers the environment: the type of every connected component is a function of its location.
Two different biphase images are studied: a cross section of a nerve from a rat, and a cross section of an optic nerve from a lizard.     

施工企业施工阶段的成本控制

施工企业的成本控制关键在于施工阶段的成本控制。传统施工企业的成本计算方法不能正确客观地反映出企业施工阶段的实际消耗。针对目前施工企业在施工阶段的成本控制中存在的一些问题,本文提出以下观点。     

论建设工程项目全过程造价控制管理方法

文章介绍了建设工程项目各阶段特点,从工程的决策阶段、设计阶段、招投标阶段、实施阶段和竣工结算阶段对工程造价控制的方法和咨询人重点工作进行阐述。     

企业物流中心规划方法研究

针对企业物流中心规划的难题,提出了五阶段的物流中心规划方法,即筹划准备阶段、总体规划阶段、方案评估阶段、详细设计阶段和实施阶段,并对每个阶段具体的工作步骤和过程模型进行了阐述。该方法对企业物流中心规划问题提供了一个科学、系统的解决框架。