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For a high laser intensity and small spot size, an electron may escape from the laser and can retain energy gain.We obtain analytical expresses of electron instantaneous momentum. Taking the plane wave of Gaussian laser for an example, we derive electron distribution function over instantaneous values of electron momentum and energy.

本文考虑电子初始温度不高(约100eV)以及脉冲长度很短(约4-6个激光波长)时，也能得到两群高能电子群；在脉冲长度极短(仅有2-3个激光波长)和电子初始温度不太高的情况下，就有明显的三群高能电子群出现，且如果激光功率密度大于5×10~(18)wcm~(-2)时，高能电子的温度也达到MeV。

For the plane wave of laser without pulse shape, we derive the express of electron trajectory by the relative Lorentz and energy equations. Note that the orbit of electron becomes a "fat-8" in the average rest frame. For the plane wave of Gaussian laser, we may know that, through relative Hamilton-Jacobi equation, electrons are accelerated in the front of pulse and decelerated backward. Whereas for the non-plane wave of Gaussian laser, we solve the Lorentz and energy equations by fourth order Runge-Kutta method.

对于无脉冲形状的激光平面波是从考虑了相对论效应的Lorentz方程和能量方程出发，得到了电子的运动轨迹方程表达式，在纵向平均速度参照系下该电子的轨迹呈现"8"字形；对于高斯型单色激光平面波是从相对论Hamilton-Jacobi方程出发，得到激光平面波在脉冲前沿加速电子而脉冲后沿减速电子，电子能量增益为零；而对于高斯型单色激光非平面波是从拉格朗日运动方程和能量方程出发，通过四阶Runge-Kutta法数值求解，得到电子在纵向有质动力、横向电场作用下加速电子，最后在强大的横向有质动力作用下从脉冲侧面散射出去，可以获得很大能量增益本文得到了相应的电子瞬时动量解析表达式。

From the point of view of geobotany, with the method of correlative factors of growth of plants, a countrywide theoretic ecological division was done for the introduction of Camptotheca acuminata and three kinds of areas of ecological preferent zone, ecological adaptive zone and ecological unadaptable zone were divided. With the theory of synecology, the characteristic on environment, constitution, life form spectrum, diversity, similarity of plots of communities were researched. Applying the method of species association, discrete distribution, indensity index, fractal geometry, etc. to research relations between the species of the communities, space distribution of Camptotheca acuminata, structure of age of Camptotheca acuminata, in different communities. Using the theories of autoecology, distibutons of seeds on land and growth of seedlings in vertical and horizontal directions, biomass of organ of Camptotheca acuminata were analyzed. On the opinions of conservation biology, the external and internal factors impressing Camptotheca acuminata were analyzed to research the mechanism of the endangered species, and with using of CTM Model, the future development direction of Camptotheca acuminata in different communities were forecasted, and. Standing on the position of resources ecology, discussing the regularity of camptothein in Camptotheca acuminata of different sites and seeding of different resources, also the the derive technics of camptothecin.

本文从地植物学的角度，运用植物生长相关因子法，对我国喜树资源的生态适宜区进行了划分，理论上确定了我国的喜树的引种栽培的最适生活区域、生态适宜区域和不适宜生活区域；从群落生态学的角度，对野生喜树所在的典型群落的群落环境、群落组成、群落生活型谱、群落的物种多样性特点、群落样地间相似性进行了研究；从种群生态学的角度，运用种间联结性、离散分布模型、聚集强度指数、分析几何等分析手段，对野生喜树所在典型群落间的种间关系、喜树的空间分布格局、年龄结构等进行了分析；从个体生态学的角度，对不同年龄组的喜树的种子的散落的垂直分布、水平分布、时间分布及种子发芽率和千里重等特点、不同种源的人工喜树苗期特点、喜树的高生长和茎生长特点、喜树的器官生物量特点进行了研究；从保护生物学的角度，对野生喜树的濒危的内部因素和外部因素进行了探讨，并运用CTM模型对不同群落中野生喜树的种群趋势进行了预测；从资源生态学的角度，对我国地理环境下喜树中喜树碱含量的地理分布规律、不同种源的喜树幼苗中喜树碱含量变化规律进行了研究，并对喜树碱的提取工艺进行了探讨。

Part Ⅰ deals with the foundmental theory of variational technique in the lossy electromagnetic fields. In chapter two and three the Green theorem is introduced so the unified method to derive functional is given. Chapter four is devoted to discuss two type of inner product. In chapter five the generialized least function theorem is given and applied in the derivation of variational expressions.

第一篇主要是关于有耗电磁变分的基础理论，由四章组成，前二章引入了以Green定理为核心的边值问题理论，建立了电磁变分的普遍理论，第四章从对称的观点出发讨论了建立泛函的两种内积形式，第五章给出了一般电磁场的广义最小作用量原理，并用之解决变分问题。

"From his studies in the late 19th century, Gregor Mendel derive d certain basic concepts of heredity, which eventually became the foundation for the modern science of genetics."

孟德尔从他在19世纪晚期的研究中，得到一些基本遗传法则，最后成为现代遗传学的基础。

The stiffeners are taken to be smeared over the surface of the element, and Hamilton＇s principle is used to derive the appropriate modifications which must be made to the plate differential equations.

对于板上加强筋的处理，则通过Hamilton原理对板的运动方程作相应的修正，最终得到加筋板的运动微分方程。

Hashish: Hallucinogenic drug preparation derive d from resin from the flowers of hemp plants.

哈希什：从大麻植物的花提取的树脂，再从中提取出的迷幻药。

Our bodies derive an abundance of hematin from food.

人体从食物中取得大量的正铁血红素。

A poisonous, crystalline alkaloid derive d from certain nightshade plants, especially Egyptian henbane.

阿托品：有毒的结晶性生物碱，从茄类植物，特别是埃及天仙子提炼而得。

Using the extended Hoare calculus we can derive true Hoare formulas which contain while statements free of loop invariants.

使用这个抽象机器，可以在其上进行许多带位操作指令的程序，特别是系统级代码的Hoare逻辑风格推理。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。