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101.
大泵站超驼峰水位运行压缩空气断流系统的设计方法 总被引:5,自引:0,他引:5
阐述了压缩空气断流的原理,提出了压缩空气断流装置的一般构成和设计方法,首次应用气体喷射器作为压缩空气减压增量变换器,不但及时地增加了补气量,防止断流后流道压力的下降,而且大大减小了储气罐容积,使该项技术得以满足工程实际的要求,为同类泵站的技术改造 相似文献
102.
气门用4Cr9Si2钢调质工艺研究 总被引:1,自引:0,他引:1
采用正交试验 ,研究了 4Cr9Si2钢的淬火温度、回火温度与组织、硬度间的关系 ,得出了最佳的工艺参数 (10 10℃淬火 ,6 0 0℃回火 )。实际生产表明 ,采用此工艺后 ,断裂现象基本消除 ,气门的热处理质量有了明显提高。 相似文献
103.
The temperature dependence of the viscosity of the undercooled melts exhibits an important role in the study of nucleation,
crystal growth and the glass-forming ability of materials. Several attempts have been made to study the viscous behaviour
of the glass-forming melts and these investigations are mainly based on free volume theory as well as on the configurational
entropy model. In the present investigation, an attempt has been made to correlate the thermodynamic parameters with the viscosity
of the glass-forming melts and to study the temperature dependence of the viscosity of undercooled liquids on the basis of
the free volume theory as well as on the basis of the configurational entropy model of Adam and Gibbs. The entire study is
confined on the expression for thermodynamic parameters reported by the authors recently. The expression obtained has been
successfully applied to study the temperature dependence of the viscosity of the metallic, molecular and oxide glass-forming
liquids. 相似文献
104.
A. N. Palagushkin S. A. Prokopenko A. P. Sergeev A. N. Arlamenkov 《Optical Memory & Neural Networks》2007,16(4):288-294
The results of experimental definition of optical parameters of silver nanolayers by the method of surface plasmon resonance
(SPR) are described. The goniometric installation for measurement of angular dependences of reflection of light by layered
nanosructures at the attenuated internal reflection (angular spectrum of reflection) is designed. Calculation of optical parameters
of nanolayers is executed taking into account the form of a curve of tin angular spectrum of reflection.
The text was submitted by the authors in English. 相似文献
105.
Development of a suitable model for characterizing photovoltaic arrays with shaded solar cells 总被引:2,自引:0,他引:2
The aim of this study is to investigate the effects of non-uniform solar irradiation distribution on energy output of different interconnected configurations in photovoltaic (PV) arrays. In order to find which configuration is less susceptible to mismatch effects, a PV module model is developed. This model can take into consideration the effects of bypass diodes and the variation of the equivalent circuit parameters with respect to operating conditions. The proposed model can provide sufficient degree of precision as well as solar cell-based analysis in analyzing large scale PV arrays without increasing the computational effort. In order to produce more reliable and robust simulations, improved and extended algorithms are presented. Some results are discussed in detail and some recommendations are extracted by testing several shading scenarios. 相似文献
106.
The static and dynamic properties of solutions of a side chain polysiloxane liquid crystal polymer have been studied in a cyanobiphenyl nematic host as a function of concentration and temperature. Refractive index measurements were carried out on aligned samples and the data used to determine the macroscopic order parameter, S, using Haller's method. Photon correlation spectroscopy has been used to measure () for the pure nematic solvent and the solutions. From these measurements it appears that the static properties vary slowly and linearly with increasing polymer concentration whilst the dynamic or viscoelastic properties change markedly. This change has been attributed to γ1, the twist viscosity, and the results have been discussed in terms of the function of the siloxane polymer backbone. 相似文献
107.
M. A. Pikin Yu. V. Nesterov 《Power Technology and Engineering (formerly Hydrotechnical Construction)》2007,41(3):159-165
A mathematical model for analysis of process parameters of equipment in the second circuit of nuclear power plants is presented,
and the structure of the program and principles used for analysis of the equipment are described. A mathematical model for
analysis of the deaerator and steam generator is described in detail. A computational analysis of several transitional modes,
which is made possible on the basis of the mathematical model in question, is also presented in this paper, and a comparison
is made with test data.
__________
Translated from élektricheskie Stantsii, No. 3, March 2007, pp. 16–22. 相似文献
108.
研究了碳含量与易切削非调质塑料模具钢性能间的关系。结果表明,随着碳含量的上升,钢的硬度随之而升高,韧性则先升后降,钢的切削性能渐趋恶化。 相似文献
109.
110.
在连续一时间控制系统中,PID控制器在各类自动化系统中应用得非常广泛。其设计技术成熟,长期以来形成了典型的结构,参数整定方便,结构变化灵活,能满足一般的控制要求。数字PID控制比连续PID控制更为优越,因为计算机程序的灵活性,很容易克服连续PID控制中存在的问题,经修正可得到更为完善的数字PID算法。 相似文献