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41.
In this article we have worked out the correlation between electronegativity and high temperature superconductivity for oxide. It is suggested the equalized electronegativity, X cq , can be used as a empirical criterion for superconductivities of oxides. For determining the X cq , a new formula for the calculation of X cq values has been obtained The X cq values of 230 oxide superconductors have been calculated. The result shows that the X cq values of all the oxide superconductors concentrate in a narrow range from 5.00 to 5.63 and that the oxides with values out side this region would be non-superconductive. This criterion can be applied to almost all the oxide superconductors. It is clearly that this result is able to benefit further inquiries about the mechanism of superconductivity.  相似文献   
42.
Complexity of mutual act and different sensation of different tourists are important factors influencing regional tourism resources evaluation. Fuzzy mathematic method can be used to up quantitative evaluation method on tourism resources evaluation. Taking Wushan Small Three Gorges as an example, the author carries out the evaluation of the tourism resources in the Three Gorges Reservoir. At the same time, the authors consider that five factors, such as improvement of the comunication of tourism resources, quickening the Steps of urbanization in reservior area, must be done well.  相似文献   
43.
It's recommended that the term coupled in temperature and strain is nonlinear and is significant in thermoelastic theory. Using the solution of linear coupled and uncoupled theory and selecting appropriate general coordinates, authers approach the nonlinear coupled problems with a variational method. A solution to the problem in half space, is given. It is shown that the difference between the nonlinear coupled theory and the linear coupled or uncoupled theory would be notable when the amplitute of temperature is much larger than that of the reference slate.  相似文献   
44.
45.
In this paper the reimprovement for G. I. Taylor theory of plastic deformation in impact of cylindical projectiles is done. The impulse in the reimproved theory is G. I. Taylor' s 1/2, and 3/4 of G. I. Taylor' s improved theory. The analytical solution of the reimproved theory shows that it gives better agreement with exprimental results than those of the original Taylor' s theory and, the improved theory.  相似文献   
46.
In this paper, taking a D1201 spindle as an example, we discuss the dynamic analysis of spindle by using the theory of the complex model, we also analyse the factors which effect the dynamic characterics of spindle and give results which arc reference value to improving the structure of spindle,  相似文献   
47.
The management of urban reconstruction is a process of game between the government and developers.It is helpful that the interest and its equilibrium for the relative parties involved in the reconstruction process are considered during the formation of government policy.This paper analyzes the environment for the policy constitution and establishes a model for strategy making based on the game theory.This model provides a basic foundation to improve the management ability of the government in the reconstruction process.Finally,in this paper some strategic issues are suggested to cope with the challenges from urban reconstruction in China.  相似文献   
48.
This peper commentaried some of our country comparatively well-known enterprise informationization estimate theory,point out,there is existing the question of informationization estimates,that the achievement can't guarantee "appropriate informationization" establishing and enterprise informationization sustainable development,It propose the three-dimensional enterprise informationization estimate the theory and method,that includes information-based level,information-based quality and information-based development potentiality.  相似文献   
49.
The aerodynamic characteristic of wind turbine is calculated by applying the Blade Element Momentum(BEM) theory.Also finite element mode analysis is done for the tower and the rotor.Then the multi-dynamic model of the wind turbine is built in Adams.Also the drive chain is calculated by applying state space method and programmed in Matlab/ Simulink.With that the combined simulation of vibration characteristics is carried out on the base of MATLAB/Simulink and ADAMS,in which the transmission effects and aero-elasticity coupling is fully considered.The results show that the method is able to simulate the vibration characteristic almost the same as software Bladed,which is well-known for analyzing performance and loads for the design and certification of wind turbines.  相似文献   
50.
In order to research the state of energy bands and gain and loss of electrons on the surface of ZnSnO_(3),it is put forward that Pinning theory of Fermi energy is applied to development of gas sensitive materials.The relative position between surface state and conduction band on surface of zinc tin complex oxide(ZnSnO_(3)) gas sensitive material has been investigated by utilizing oxidation redox couple,FeCl_(2)/ FeCl_(3),which have high surface state.Fermi energy is pinned at about 0.2 eV below conduction band E_(cs)on the surface of ZnSnO_(3).It has been determined that additives doping ratio,addition concentration and working atmosphere have no effect on this value.Therefore,pinning theory of Fermi energy has been verified by using this method.  相似文献   
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