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51.
An improved mathematical model for a circulating fluidized bed (CFB) boiler based on the model developed earlier by the authors was applied to simulate the operation of a 12 MW CFB boiler. The influences of the excess air ratio, primary air ratio, coal particle size distribution, coal properties (ash content and volatile content) and Ca/S ratio on the boiler operation were analyzed. The results showed that the model simulation may be applied to the optimum design and economic operation of the CFB boiler. 相似文献
52.
论王朔写作动机的嬗变历程 总被引:1,自引:0,他引:1
利用“心理分析理论”研究王朔的写作动机,还王朔本原的写作形象,从写作动机观照一个作家从浅薄到真诚,从成熟到浮躁的嬗变轨迹,进而深入了解颇具争议的“王朔现象”,王朔的创作很形象地体现出一个作家成长的过程,它会给年轻作家或者文学爱好者的成长提供可供参考的范例。 相似文献
53.
现代公司中,董事会职能不断分化,经营意思决定,具体业务执行及监督三种职能相对独立;与此相应,外部董事,职工董事被不断引进,董事会的构成得以革新。我办公司立法,应顺应历史潮流,构建有自己特色的“三元结构” 董事会。 相似文献
54.
Development of an evaporation crystallizer for desalination of alkaline organic wastewater before incineration 总被引:2,自引:0,他引:2
A wastewater evaporation-desalination pretreatment method was introduced to remove the Na^+ and K^+ salts in volatile organic compounds (VOCs) wastewater before it was fed into the incinerator. VOCs in the wastewater were volatilized in the evaporation system and then the vapor was combusted in an incinerator. Simulated phenol wastewater containing sodium chloride was evaporated and concentrated and sodium chloride was crystallized in different parameters. The experimental results showed that the higher initial concentration of sodium chloride increases the ratio of volatilization of VOCs, which was due to the effect of “salting out” (a decrease in the solubility of the nonelectrolyte in the solution, or more rigorously, an increase in its activity coefficient, caused by the salt addition (Furter and Cook, 1967)). When evaporation speed was increased from 1.67 ml/min to 2.73 ml/min, the total removal coefficient of sodium chloride was about 99.88%-99.99%. This pretreatment procedure eliminates the slag phenomenon caused by Na^+ and K^+ salts during wastewater incineration, so the incinerator could operate continuously, and the wastewater evaporation could increase the heat value of wastewater, and the operation cost would be reduced. 相似文献
55.
加强血液质量管理是血站管理工作的核心问题,是安全输血的重要前提条件。本文探讨了中心血站如何从提高工作人员的认识和自身素质,通过确定全面质量管理的基本指导思想,采取法制化管理与标准化管理并举和三级管理体系,以及通过引进国际质量体系来加强血液质量管理。可以借助科技进步来促进血液质量管理。 相似文献
56.
LIU Dong WANG Fei HUANG Qun-xing YAN Jian-hua CHI Yong CEN Ke-fa 《浙江大学学报(A卷英文版)》2007,8(11):1853-1857
Radiative imaging of combustion flame in furnace of power plant plays an increasingly important role in combustion diagnosis. This paper presents a new method for calculating the radiative imaging of three-dimensional (3D) combustion flame based on Monte Carlo method and optical lens imaging. Numerical simulation case was used in this study. Radiative images were calculated and images obtained can not only present the energy distribution on the charge-coupled device (CCD) camera target plane but also reflect the energy distribution condition in the simulation furnace. Finally the relationships between volume ele- ments and energy shares were also discussed. 相似文献
57.
通过采用了北京师范大学外语系的程晓堂和郑敏两位学者的英语学习策略调查表对新疆师范大学汉语教育学院的对外汉语本科05级的同学进行了英语学习策略的诊断;用文秋芳博士的性格测量表对该班同学的性格特点进行了分析。结果发现不同性格的学生学习策略的使用情况也各不相同;而通过皮尔逊相关系数的计算发现学习策略与学习成绩两个变量的相关性很强,即:学习策略使用得越多,学习成绩越好。 相似文献
58.
59.
The combustion behavior of typical components of MSW was examined with a thermal gravimetric analyzer (TGA). The experiments were done over the temperature range of room temperature to 1000℃ at a heating rate of 10 oC/min and in an oxidizing atmosphere. The results indicated that the entire weight loss process of each typical component of MSW consists of one to three distinct combustion stages. The combustion of typical components of MSW could be modeled by one to three independent reactions. The corresponding parameters of typical components of MSW such as activation energy, pre-exponential factor, and reaction order were determined. The calculated results using the comprehensive kinetic model composed of one to three independent and consecutive reactions, agreed well with experimental results. 相似文献
60.
本文首先推导出圆极化光波对原子波包平均作用力的一般表达式,然后以高斯波包为例计算了其所受的平均作用力,用计算机绘出了它随时间变化的曲线,并对该平均作用力做了详细的讨论。 相似文献