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系统分析了黑龙江穆棱地区巨晶斜方辉石的性质、化学成分和光谱学特征。电子探针(EMPA)的分析结果表明,该巨晶斜方辉石属于斜顽辉石,其元素组成包括Ca,Na,Mg,Fe,Al,Ti,Si和O, 结构水含量为20~130 ppm。拉曼光谱(Raman)的特征峰位于1 015,678和345 cm-1,分别由不同的振动类型引起。傅里叶红外光谱(FTIR)的分析表明巨晶斜方辉石在官能团区具有三个明显的吸收峰,它们分别位于3 550~3 590,3 510~3 520和3 410~3 420 cm-1,与幔源辉石结构水的吸收峰较为一致;对巨晶斜方辉石的红外微区含水量测试分析表明,结构水在不同巨晶斜方辉石间存在差异,但在单一辉石样品内部分布均匀,无明显核-边变化。 相似文献
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This paper concentrates on the numerical solution of the exterior trajectory of grenades.We consider the model with six degrees of freedom,which is an initial value problem of an ordinary differential system with twelve variables.Due to the high oscillating property of the equations,only very small time steps must be used when the explicit Runge-Kutta methods are applied,which leads to an unsatisfying efficiency.In this paper,we use the skill of asymptotic expansion to obtain the analytical expressions of the approximate solutions of two variables.Thus the oscillations in the solutions are significantly reduced,and the time step can be enlarged intrinsically.Numerical examples show that the efficiency is effectively enhanced by this method. 相似文献
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A continuous method is presented to deal with the discontinuous physical properties on both sides of solid/liquld interface during the solidification process. Then single dendrite evolution in two and three dimensions is simulated by using this method. Multi-grain evolution is also simulated during solidification by the method. The method is easy to be understood and does not need all details of dendrite. The simulated results can reflect the random characteristic of dendrite evolution and the micro-segregation of solute. 相似文献
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编写了适用于模拟具有高密度比、高压力比的强激波问题的二维柱对称多介质流体计算程序。利用有限体积方法求解流体的Euler方程组,采用level set方法捕捉爆炸产物与空气的运动界面,并通过求解物质界面两侧Riemann问题的精确解来计算爆炸产物与空气之间的数值通量。研制了三角形网格自适应技术来实现网格的自动加密和粗化,在保证捕捉激波峰值的前提下有效地提高了计算效率。利用计算程序对1 kt TNT当量的空气自由场强爆炸问题进行数值模拟,计算得到的峰值超压、冲击波到达时间等物理参数与点爆炸理论结果基本一致。 相似文献
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