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101.
何永佳 《武汉理工大学学报(材料科学英文版)》2013,28(3):544-547
Porous haydite used as waste filter medium was prepared by dreging lake sludge to help solve the treatment problem of sludge and realize its reclamation. Several calcination regimes were considered and their effects on the pore structure and the properties such as the strength, the density, the filtering ability and the phosphate absorption ability of the haydite were investigated. For the mixture of 60% lake sludge and 40% fly ash in this experiment, the calcination regime with a pre-calcination period at about 600 °C, a temperature keeping period at 1 200 °C and a moderate cooling rate are recommended to prepare haydite with reasonable pore structure and good performances for its usage as the waste water filter media. 相似文献
102.
为了解决我国城市社区网站建设中所存在的问题,如社区事务繁杂、建设资金缺乏、信息类人才短缺等,对社区与其他组织所建立起来的稳定合作关系进行探索研究,主张发掘利用大学生志愿者资源来有效解决社区资金和信息化人才短缺的问题,从而使高校为社区网站建设提供长期、稳定的智力支持和技术支持。 相似文献
104.
中国漆文化遗产保护调查研究之二 总被引:1,自引:0,他引:1
云雕是漆器的一种。通常用红黑两色漆交替髹涂,然后雕刻花纹,刻纹侧面显出红黑相间的线纹。多雕成云状,故又称“云雕”,也即剔犀。 相似文献
105.
106.
Photochromism in composite and hybrid materials based on transition-metal oxides and polyoxometalates 总被引:1,自引:0,他引:1
Tao He 《Progress in Materials Science》2006,51(6):810-879
Photochromic materials are attractive and promising for applications in many fields. One subject in this area is to prepare and study the photochromism in composite or hybrid materials based on transition-metal oxides or polyoxometalates. Their properties not depend only on the chemical nature of each component, but also on the interface and synergy between them. Since the charge transfer plays a key role in the photochromism of these materials, it is very important to increase the charge (electrons, holes, and protons) interactions between the two components in either composites or hybrids. To realize this, one big challenge is to optimize the two components on a molecular or nanometer scale, which is closely relevant to the constituents, sample history (pre-treatment, preparation, and post-treatment), environment (humidity, presence of reducible or oxidizible matters, light-irradiation wavelength, intensity, time, etc.). Based on these, many novel composite or hybrid materials with improved photochromism, visible-light coloration, reversible photochromism, multicolor photochromism or, possibly, fast photoresponse, have been prepared during the last two decades or three. This may underscore the opportunity of using these composite and hybrid materials as the photonic applications. In present paper, we summarize thoroughly all the recent progress in these subjects. 相似文献
107.
An interpolation model to accelerate the frequency-domain response calculation of grounding systems using the method of moments 总被引:1,自引:0,他引:1
The transient characteristics of grounding systems are essential for their designs and related electromagnetic-compatibility problems in power systems. Although the method of moments (MoM) is a popular way to analyze the characteristics of grounding systems, it is time-consuming. In this paper, a two-stage method is presented to construct fitted models of the frequency-domain responses of grounding systems to accelerate the calculations of the MoM. In the first stage, the adaptive model-based parameter estimation is used to adaptively choose the most valuable frequency sampling points to construct the initial fitted functions, and then the fitted functions are adjusted in the second stage by comparing the fitted results with those computed by the first principle model at some points. The validation was achieved by a comparison of the numerical results and those obtained by inverse fast Fourier transformation. 相似文献
108.
炉温变化时硬质合金真空烧结炉的时滞常数变化很大,常规PID控制不能同时在高温段与低温段满足生产工艺提出的控制品质要求。本文在利用最小二乘法拟合出真空烧结炉时滞常数与炉温变化函数的基础上,PID参数采用经典的CHR整定算法随炉温变化实时整定,并利用MAT—LAB仿真软件对该控制算法在真空烧结炉中的应用进行了仿真研究,结果表明该算法能够实现对真空炉的有效控制,控制系统能够满意地跟踪设定的温度曲线。 相似文献
109.