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1.
钙钛矿型复合氧化物的结构及制备方法研究 总被引：1，自引：0，他引：1
钙钛矿型ABO3复合氧化物是一类性能优良的新型功能材料,具有广阔的应用前景,本文介绍了钙钛矿型复合氧化物的晶体结构;概括了其制备的主要方法,包括固相反应法、溶胶一凝胶法、水热法以及化学共沉淀法和微乳液法． 相似文献
2.
LaCoO3光催化降解水溶性染料 总被引：2，自引：0，他引：2
采用柠檬酸络合法制备钙钛矿型复合氧化物LaCoO3 ,以荧光汞灯和太阳光为光源对各种不同的水溶性染料进行光催化降解实验 .结果表明 ,钙钛矿型复合氧化物LaCoO3 具有很好的光催化活性 ,根据X射线光电子能谱和光声光谱分析得知 ,LaCoO3 的光催化活性主要与Co3 + 的d电子结构、Co—O结合能以及表面吸附氧有关 相似文献
3.
与钙钛矿ABO3型氧化物材料进行比较,阐述了双钙钛矿A2BB＇O6型氧化物材料的某些电磁特性及掺杂效应。 相似文献
4.
用混合氧化物法制备钙钛矿型复合氧化物ＰｂＴｉＯ３，提出较合适的制备条件。制得的ＰｂＴｉＯ３纯度高，颗粒均匀，细度较好．在ＰｂＴｉＯ３悬浮水溶液中染料的光催化脱色率超过９０％。 相似文献
5.
钙钛矿锰氧化物R1-xAxMnO3具有丰富的物理现象,其在磁存储及传感技术等方面都具有诱人的应用前景。从介绍钙钛矿锰氧化物R1-xAxMnO3的电磁性质入手,对钙钛矿锰氧化物的电磁输运性质的研究进展进行了综述,详细分析了锰氧化物电子型掺杂的研究重点,并展望了锰氧化物的应用前景。 相似文献
6.
以开发固体氧化物燃料电池（SOFC）新型阴极材料为目的,采用高温固相反应法合成了一系列钙钛矿型复合氧化物La0.8Sr0．2Mn1-yCOyO3-δ（LSMC,Y分别取0.3,0．5和0．7）,并对Mn位掺杂不同量过渡族元素Co后样品的高温电导率和热膨胀系数进行了研究,发现随着Co含量的增加,材料的电导率和热膨胀系数均增大,其中La0.8Sr0．2Mn0.3Co0.7O3-δ的电导率最高,700℃时,达270．89S·cm^-1。 相似文献
7.
固体氧化物燃料电池的研究进展 总被引：1，自引：0，他引：1
文章介绍了几种主要燃料电池的发展和研究现状、固体氧化物燃料电池(SOFC)的工作原理和特点,综述了SOFC的主要组件(阴极、阳极、电解质材料)制备方法及其进展,对SOFC在能源开发利用与市场化的前景进行了展望。 相似文献
8.
研究了钛的复合氧化物作为新型电流变材料的制备、性能测试,确定了以钛、锶复合氧化物吸附稀土氢氧化物制备的电流变材料的很好的响应,同时对复合氧化物的制备条件进行了探讨。 相似文献
9.
概述固体氧化物燃料电池 (SOFC)的原理 ,综述了ZrO2 基固体电解质型燃料电池的研究进展状况 ,提出了一些有待解决的问题 相似文献
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钙钛矿型氧化物由于其结构的稳定性和特殊的物化性能,日益成为材料科学领域的研究热点.本文简要介绍了钙钛矿型氧化物的化学结构及其性能以及制备方法和应用的研究现状,综述了近年来钙钛矿型氧化物在催化及其他领域的研究进展. 相似文献
11.
The operating temperature of a solid oxide fuel cell （SOFC） stack is a very important parameter to be controlled, which impacts the performance of the SOFC due to thermal cycling. In this paper, an adaptive fuzzy control method based on an affine nonlinear temperature model is developed to control the temperature of the SOFC within a specified range. Fuzzy logic systems are used to approximate nonlinear functions in the SOFC system and an adaptive technique is employed to construct the controller. Compared with the traditional fuzzy and proportion-integral-derivative （PID） control, the simulation results show that the designed adaptive fuzzy control method performed much better. So it is feasible to build an adaptive fuzzy controller for temperature control of the SOFC. 相似文献
12.
The Educational Forces Inventory (EFI) is a technique for assessing the constellation of forces in the teacher’s social-psychological field. Thereby, important stress points for teachers are identified and their work in the classroom is facilitated. The EFI charts the relative influence of each of 13 forces that are important factors in the educational settting. Teachers are asked to characterize each force along two dimensions: the amount of influence it exerts upon the classroom process, and the degree to which this influence is positive or negative. Several hundred teachers and teaching assistants in Follow Through classrooms throughout the country participated in a field test of the instrument, with concurrent administration of the Purdue Teacher Opinionaire (PTO), an established measure of teacher morale. The high rate of return and correct completion on the EFI indicated that it is a practical technique. In addition, the data indicated validity for the instrument in three important respects: (1) the pattern-of-importance ratings correspond to independently assessed patterns of physical and social distance; (2) the positive/negative ratings for particular forces correlated substantially with corresponding subscores of the PTO; and (3) the pattern of responses reflected aspects of internal consistency. Some ways of utilizing EFI data are discussed: how to plot and interpret two-dimensional force fields, and how to use them in program implementation, especially to facilitate the work of the teacher in the classroom. 相似文献
13.
燃料电池是一种等温并直接将储存在燃料和氧化剂中的化学能高效、环境友好地转化为电能的新型发电装置．燃料电池不受热机效率的限制，能量转换效率高，无污染、无噪音，具有满足环境保护的要求．预计燃料电池系统将在洁净煤燃料电池电站、电动汽车、移动电源、不间断电源、潜艇及空间电源等方面有着广泛的应用前景和巨大的潜在市场．本文介绍了燃料电池的的优点、主要种类、工作原理、国内外发展概况以及燃料电池的前景展望。 相似文献
14.
Isyraf Aznam Joelle Chia Wen Mah Andanastuti Muchtar Mahendra Rao Somalu Mariyam Jameelah Ghazali 《浙江大学学报(A卷英文版)》2018,19(11):811-823
This paper reviews recent progress in electrophoretic deposition (EPD), particularly in solid oxide fuel cells (SOFCs). EPD is a simple, cost-effective, and geometrical flexible colloidal process. With its excellent control of thickness and other morphological characteristics, it is favored for the fabrication of SOFCs because each component layer of an SOFC has different requirements. However, the effectiveness of EPD is closely related to the suspension stability and EPD processing parameters. Maintaining a stable suspension and optimizing the EPD processing parameters are essential to achieve a dense and uniform deposition layer. Key parameters in maintaining the suspension stability are generally categorized into colloidal related parameters, including particle size and solid loading, and suspension media related parameters, including dielectric constant and conductivity. The effects of these parameters are often reflected by the zeta potential of the suspension, which can be manipulated by using charging agents to maintain a stable state. The deposition time and applied voltage are key parameters in optimizing the EPD process through their effects on the deposition rate. The effects of these parameters on particle surface charges and on the EPD mechanism are discussed. 相似文献
15.
PLC在变频调速恒压供水系统中的应用 总被引：1，自引：0，他引：1
本文详细地介绍了三菱公司FX系列小型PLC在小区高楼恒压供水系统中的应用，并具体说明了系统工作原理和控制系统的设计。实际系统中由一台变频器和自耦降压启动器带动多台水泵，采用PLC实现PID调节和水泵的工频、变频运行切换。现场运行表明，该系统自动化程度高，稳定性好，完全符合工艺要求。 相似文献
16.
课程效能评价——以“教育效能与教育评价”为例 总被引：3，自引：0，他引：3
“教育效能与教育评价”课程以个人的、团队的、组织的(PTO)效能和规划、实施与评价(PIE)代表其内容与过程的主要结构。教师以双语教学——中英文的阅读材料、学习指南、课程纲要和视听讲座的形式，采取具有高度互动性的学习方式，如个人与小组层次的讨论、比赛、模拟、奖励、批判性反思，向50名来自中小学、大学和行政机关的高层教育领导者授课，以增加课程的效能。文章所展示的就是如何应用课程中有关效能与评价的基本原理评价这一课程本身的效能。 相似文献
17.
WU Xiao-juan ZHU Xin-jian CAO Guang-yi TU Heng-yong 《浙江大学学报(A卷英文版)》2007,8(9):1505-1509
The solid oxide fuel cell (SOFC) is a nonlinear system that is hard to model by conventional methods. So far,most existing models are based on conversion laws,which are too complicated to be applied to design a control system. To facilitate a valid control strategy design,this paper tries to avoid the internal complexities and presents a modelling study of SOFC per-formance by using a radial basis function (RBF) neural network based on a genetic algorithm (GA). During the process of mod-elling,the GA aims to optimize the parameters of RBF neural networks and the optimum values are regarded as the initial values of the RBF neural network parameters. The validity and accuracy of modelling are tested by simulations,whose results reveal that it is feasible to establish the model of SOFC stack by using RBF neural networks identification based on the GA. Furthermore,it is possible to design an online controller of a SOFC stack based on this GA-RBF neural network identification model. 相似文献
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19.
研究目的：为了同时预测固体氧化物燃料电池（SOFC）的电压、温度动态特性和设计控制器,建立SOFC的控制相关动态辨识模型。创新要点：为了建立SOFC更精确的最小二乘支持向量回归机（LSSVR）动态模型,采用遗传算法（GA）优化LSSVR的参数。所建GA-LSSVR模型可同时预测SOFC的电压和温度动态特性。研究方法：1.分析SOFC的电化学和能量平衡子模型。2.利用所选择的最优LSSVR参数,建立了SOFC的GA-LSSVR动态辨识模型。通过仿真分析和比较,验证了所建模型的有效性（图3和4）。3.利用所建模型的预测结果,与模拟退火算法优化最小二乘支持向量回归机（SAA-LSSVR）和5折交叉验证最小二乘支持向量回归机（5FCV-LSSVR）模型的预测结果进行了比较,表明所建立的GA-LSSVR模型具有较高的预测精度（表3和4）。重要结论：通过比较SAA-LSSVR和5FCV-LSSVR模型的预测结果,发现所建GA-LSSVR模型具有较好的预测性能和精度。基于所建立的GA-LSSVR模型可进行有效的多变量控制器设计。 相似文献
20.
The Car-following models is a kind of microscopic simulation model for vehicular traffic, which describe the one-by-one following
behaviors of vehicles in the same traffic lane. As a common traffic phenomenon, following behavior is of great importance
in the micro-study of intelligent traffic control. Compared with other traffic-flow models, car-following model embodies the
human factors and reflects the real traffic situation in a better way. This paper gives a systematic review of the development
and actuality of car-following models by introducing and analyzing in detail the advantages and disadvantages of GHR model,
OV model, CA model and fuzzy-logic model. In addition, local stability and asymptotic stability of car-following models are
discussed in this paper. 相似文献