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81.
刘雅丽 《沈阳大学学报:自然科学版》2008,20(3):78-80
从培养目标、培养模式、培养过程、培养内容、培养方法、培养手段等六个方面阐述高校创新教育,有针对性地提出高校创新教育内涵和实现创新教育的主要途径。 相似文献
82.
魏毅 《淮北煤炭师范学院学报(自然科学版)》2007,28(3):65-68
在田径教学、训练与比赛中,由于没有完全遵循人体运动的生理规律和调控生物节律,不能使机体的工作运行保持在良好的竞技状态,导致各种各样的运动创伤,严重地影响教学、训练与运动成绩的提高.文章从运动医学理论对田径运动中肌肉损伤的原因进行分析,寻找科学的田径运动损伤康复手段。 相似文献
83.
84.
文章从企业组织,员工队伍,经营业务领域以及经营发展轨迹出发,以企业经营所处的宏观环境与微观环境为切入点,对企业在竞争中的优势与劣势,以及企业在经营与发展所处环境中面临的机会与威胁进行了分析。 相似文献
85.
By further generalizing the skew-symmetric triangular splitting iteration method studied by Krukier, Chikina and Belokon (Applied Numerical Mathematics, 41 (2002), pp. 89–105), in this paper, we present a new iteration scheme, called the modified skew-Hermitian triangular splitting iteration method, for solving the strongly non-Hermitian systems of linear equations with positive definite coefficient matrices. We discuss the convergence property and the optimal parameters of this new method in depth. Moreover, when it is applied to precondition the Krylov subspace methods like GMRES, the preconditioning property of the modified skew-Hermitian triangular splitting iteration is analyzed in detail. Numerical results show that, as both solver and preconditioner, the modified skew-Hermitian triangular splitting iteration method is very effective for solving large sparse positive definite systems of linear equations of strong skew-Hermitian parts. 相似文献
86.
The rational and sustainable exploitation of nature resources is one of the priority objectives of our society. In this article a method is proposed to evaluate and exploit the energetic resources contained in different forest formations. This method is based on the use of a combustion bomb calorimeter to determine the calorific values of the different samples studied. These results were complemented with chemical analysis of the samples and with environmental and geomorphological studies of the zones were samples were taken. The results obtained during the last 3 years for the residual biomass originated from the forest formations existing in Galicia ensure the reliability and usefulness of the method that can be extended to any forest formation all over the world. 相似文献
87.
Basic principles of the generalized lattice model of multicomponent condensed systems are formulated. Short-range parts of interatomic interactions are taken into account by means of the geometric constraints method. Long-range parts of the interactions are taken into account in mean field approximation. The expression for Helmholtz free energy is obtained. A system of integral equations for the equilibrium distributions of components is derived. The asymptotic properties of its solutions are investigated. Moment expansion of interatomic interactions and localization of integral terms in free energy is obtained. A Ginzburg–Landau-like functional of free energy is derived. 相似文献
88.
Teresa uczak Radosaw Pankiewicz Bogusawa ska Grzegorz Schroeder Maria Betowska-Brzezinska Bogumil Brzezinski 《Journal of Molecular Structure》2006,800(1-3):140-145
Novel self-assembled monolayers were obtained on silver using 4,7-diazaheptyl-trimethoxy-silane (SiN) and vinyl-trialkoxy-silane (SiVA, where the alkyl group is 3,6,9,12,15,18,21,24,27,30,33,36,39,42,45,48,51,54,57,60-eicozaoxa- hexaheptaconan). It was shown that thus modified metal surface was protected against electrooxidation. A densely packed monolayer remained stable and did not desorb from the Ag electrode on the potential cycling. The structure of SiN and SiVA as well as their complexes with Li+ cations were calculated and visualised by the AM1d and PM5 semi-empirical methods. 相似文献
89.
I.A. Khotina L.S. Lepnev N.S. Burenkova P.M. Valetsky A.G. Vitukhnovsky 《Journal of luminescence》2004,110(4):232-238
New materials based on low-generation polyphenylene dendrimers with the light emission in the blue spectrum range were synthesized and examined for an efficient organic light emitting diodes (OLED) application. It has been shown that the ratio of p-phenylene groups with high fluorescence parameters to 1,3,5-triphenylbenzene groups with low fluorescent parameters may be the possible reason for the experimental variations of relative quantum yield of photoluminescence in the compounds explored. The quantum yield value is increased with a number of dendrimer generations up to 50–70%. The role of bromine atoms as the luminescence quenchers have been demonstrated, which is important for synthesis route choice. 相似文献
90.
本文考察了包括平面上的各种广义 Cantor集 ,Sierpinski集和包括某些连续不可微曲线在内的广义 Sierpinski集 .由相似变换 ,导出了它们的级数表达式 ,并利用它和字符串空间的对应关系 ,计算出它们的Hausdorff维数 相似文献