近似公式

Using the theory of radiative capture reaction and combining our department experiment, we investigate two nuclear reactions,〓 and 〓, and calculate the cross sections and astrophysical reaction rate of them.

我们对ANC系数的近似模型无关性给出了一个数学形式理论证明，并结合具体的核反应，利用数值计算验证了ANC系数的近似模型无关性；在E1跃迁情况下，我们给出了一个用ANC系数计算辐射俘获反应截面的计算公式。

In order to solve the problem,starting from the analysis of the simplest plane wave numerical theory,we derived the formula of relative phase velocity and group velocity under the condition of arbitrary high-order finite-difference approximation,and gave the computational method for acquiring the optimum Courant number,and then analyzed the anisotropic effects due to finite difference approximation.

针对此，从最简单的平面波数值理论分析出发，推导了任意高阶有限差分近似条件下相对相速度和相对群速度的计算公式，给出了求解最佳Courant数的计算方法，分析了差分近似造成的各向异性效应。

Based on point explosion theory , the approximate analytical formulas of momentum coupling coefficient and impulse of cone and parabolic crafts are deduced. The results show that the total axial impact momentum for parabolic craft is larger than that of cone craft and it increases with the increase of half open angle.

以LSD/LSC波理论为基础建立了一个近似的理论解析模型，推导出圆锥形和抛物形飞行器获得的冲量及冲量耦合系数的近似解析表达式，公式表明冲量耦合系数随着半张角的增加而增加，同时抛物形飞行器要比圆锥形飞行器的动量汇聚效果好。

Algorithm for determining the lower limit of the iterated times in IFSP;2. Stratigraphical division and lower limit of the Quaternary in Hunan;3. At present, the approximate solution of Voigt and Reuss's upper limit or lower limit and the calculating formula of Hashin and Shtrikman's upper limit or lower limit are accurate.

计算复合材料有效弹性模量上、下限的方法中，Voigt和Reuss的上、下限近似解及Hashin和Shtrikman的上、下限计算公式较为精确，但Voigt-Reuss近似解通常忽略了各向异性非均匀体的研究，是一个不全面的结果。

While the new components having the same numbers with these original physical vectors are introduced and the new components are combined with those original physical components to form a new symplectic space, the ray problem of wave propagation in geometrical optics is converted into the problem of Lagrange submanifold in the symplectic space.

本论文的工作作为国家自然科学基金地震波传播与成像项目（NO.40174032）的一部分，得到如下结果：论文分析了利用Maslov方法求解非均匀介质中波动方程高频近似解的基本原理和求解过程，构造了介质系数只在一个方向变化时波动方程高频近似解的通用计算公式。

For the application of Mathematica in the differential geometry,this paper introduces how to processe the curve curvature and the torsion questions,the graphic expression of the curvature and the torsions,and draw curves by the curvature and the torsions. Curvature ; torsion ; solution curve ; osculating plane ; natural parameter ; natural equation

利用Mathematica，只要输入有关系统命令就可以得到期望的结果。1曲率和挠率及其图形意义假设R3上的曲线一般参数表示为r=r它的曲率和挠率计算公式是：κ=‖r′×r"‖‖r′‖3τ=‖r′×r‖我们知道，空间曲线r=r在一点(s=s0)邻近的近似方程为ξ=sη=120κs2ζ=160κ0τs3通过近似方程可以确定曲线在其基本三棱形的三个平面(即密切平面，法平面，从切平面)上的投

The fields radiated by these currents in the presence of curved earth are then calculated using the reciprocity theorem and the known ground wave propagation formula of a vertical electric dipole S.

在数值结果验证了该公式的正确性之后，对海面上一金属半球的散射场进行了求解，并以此与工程应用中的近似方法相对比，考察了工程应用方法的近似程度。

It presented a practical approach for calculating the approximate second-order elastic moment of the partially-braced frame column, based on the present design code of steel structures and the approximate magnification factor of second-order moment of unbraced frame column.

摘要］在现行钢结构设计规范的基础上，结合无支撑纯框架柱二阶近似弹性分析的二阶弯矩放大系数，提出了用于弱支撑框架柱考虑侧移效应的二阶近似弯矩放大系数实用公式。

Experimental results show that the zero effort miss vector calculated by using approximate formulas is close to the real miss vector. Under the conditions of small initial errors, the satisfied results can be obtained by approximate function. The zero effort miss vector obtained can be used for the preliminary design and analysis of kinetic interceptor guidance.

测试结果表明该近似算法得到的零控脱靶量与真实值比较接近，在较小初始偏差条件下，简化的近似计算公式能给出满意的结果，所得零控脱靶量可用于空间动能拦截制导系统的初步设计与分析。

It was also found that the estimation of incident energy associated with energy transfer to the surface adatom could be employed in guidance of the experiments, although some approximations were introduced in the proposed model.

尽管在计算模拟中引入了一些近似，公式中也没有考虑离子、原子流比值和温度效应，但是，离子向表面增原子能量转移的近似计算结果，仍具有指导实验的预言性和适用性。

Cynanchum Lingtai apricot production in the average weight 65 grams, the brightly-colored fruit, juicy rich, sweet-sour taste, sweet from the nucleolus, when the late Qing Dynasty famous Shaanxi, Gansu provinces, the Qing imperial court Tongzhi tribute for years.

灵台生产的牛心杏平均单果重65克，果实色泽鲜艳，汁多味浓，甜酸适口，离核仁甜，清末时就驰名陕、甘两省，清同治年间曾为朝廷贡品。

Chenopodium album,Solanum nigrum, and Amaranthus retroflexus were very susceptible to the herbicides. Polygonum persicaria and Abutilon theophrasti were relatively less susceptible to the herbicides, and Lycopersicon esculentum was not susceptible to it. The relationship between reduction rates of weed biomass and PPM values of weed leaves 2,4, and 6 days after treatment was established.

供试的6种杂草对该混剂的敏感性存在显著差异：红心藜Chenopodium album、龙葵Solanum nigrum和反枝苋Amaranthus retroflexus对该混剂最敏感，ED90值分别为47.65、71.67和29.17g/hm2；春蓼Polygonum persicaria和苘麻Abutilon theophrasti敏感，ED90值分别为96.91、114.20g/hm2；而番茄不敏感。