步骤

Fourth, according to the work requests of this thesis and using the knowledge of analytic geometry, the math model needed by programming is created.

详细介绍了在Unigraphics环境下的二次开发步骤，对每一个细节部分都做了较细致的说明。

The design of four-mirror anastigmat was analyzed, then a system with effective focal length of 1 200 mm and field of view of 0.8°×0.8° was designed , total length and f-number are 300 mm and F/6,respectively.The system has advantages of long focal length, relative short physical size and excellent ability in restraining stray lights.

分析了离轴四反的设计步骤，设计了一个焦距为1 200 mm，视场为0.8°×0.8°，相对孔径为F/6的光学系统，系统总长只有300 mm，并达到很好的光学性能，具有长焦距、小尺寸、良好的杂散光抑制能力等特点。

These components are intricately related and must be anatomically visualized in every step of the rhinoplasty sequence.

这些组成部分构成一有机整体，在每一步的鼻整形步骤中都必须辨明其解剖结构。

The genetic inactivation of eggs is the first key stage of androgenesis in fish. In order to observe the effect of UV irradiation for the inactivation of female nucleus of zebrafish the eggs were irradiated by UV with solution-free, pure water, Ringer's solution and Cortland solution. The results showed that abnormal fry were obtained in all groups and haploids were validated. But irradiation with solution was confirmed it could not inactive fully female nucleus and the fertilization rate of the eggs irradiated with pure water was very low.

雌核灭活是雄核发育的第一个关键步骤，为研究紫外线对斑马鱼卵的雌核灭活效果，将斑马鱼的卵采用干法或置于纯水、Ringer氏溶液和Cortland鱼用生理盐水进行紫外线照射，结果表明，各种方法中均得到畸形鱼苗，并经染色体检查大多为单倍体；四种方法中在Cortland鱼用生理盐水中灭活效果最好，120 mJ/cm2紫外线可以使雌核完全灭活；干法处理不能达到雌核完全灭活的目的，在纯水中灭活后的卵子受精率较低。

First, the paper discusses microwave anechoic chamber design techniques before the reflectivity level of quiet zone is calculated.

在对暗室静区反射率电平进行计算以前，本文先讨论了微波暗室的设计，主要可分为以下几个步骤： 1。

This text is to the management current situation and demand of the school, from the theory and angle characteristic , function , mentality of designing of describing student's information management system used, provide the step of key technology.

本文针对学校的管理现状和要求，从理论和应用的角度论述了学生信息管理系统的特点、功能、设计思路，并给出关键技术实现的步骤。

And describes the measuring procedures of the contact angle between mercury and solid dielectric by using an experiment.

简单介绍了固液接触的基本理论以及接触角各种主要的测量方法，包括躺滴和悬泡接触角测量方法、Wilhelmy吊片法等，进而通过实验叙述了水银与固体电介质表面接触角的测量步骤等。

This paper investigates the effects of high temperature on ultrasonic velocity, refraction angle of inclined probe, ultrasonic attenuation, emitting strength of ultrasonic probe and defect detectable ratio, and provides practical methods of high temperature ultrasonic inspection for vessels and equipment, as well as concrete inspection procedure and key operational points.

文章通过研究高温对超声波声速、斜探头折射角、超声波衰减、探头发射超声波强度以及缺陷检出率的影响，提出了对容器设备进行高温超声波检测的方法、具体检测步骤和操作要点等。

The integral area for calculating the beam width by using the definition of generalized second-order moments is selected to ensure the energy in the angular domain more than 75% of the total beam energy and the measurement method and steps still follow the relevant ISO standards. The generalized M2 factor of truncated Gaussian beam has been measured. The experimental results for different truncated parameters have been compared with the theoretical results, showing the validness of the method proposed.

在利用广义强度二阶矩计算光束束宽时，以积分角谱范围能够包含光束总能量的75%以上作为积分范围的选取标准，并遵循现有的国际标准化组织规定的测量步骤和方法对截断高斯光束的广义M2因子进行了测量，并将不同截断参量时的实验结果与理论计算结果进行了比较，证明了该方法的正确性。

Dihydroxy-7, 4′-dimethoxy-dihydrflavonol and -3, 5, 7 -trihydroxy-4′-methoxy- dihydrflavonol were synthesized by selective protection, condensation, epoxidation, cyclization and deprotection from 2, 4, 6-trihydroxyacetophone and anisaldehyde.

以2，4，6-三羟基苯乙酮和茴香醛为起始原料，经选择性保护、缩合、环氧化、关环等步骤首次完成了-3，5-二羟基-7，4′-二甲氧基二氢黄酮醇和-3，5，7-三羟基-4′-甲氧基二氢黄酮醇全合成。

It has been put forward that there exists single Ball point and double Ball points on the symmetrical connecting-rod curves of equilateral mechanisms.

从鲍尔点的形成原理出发，分析对称连杆曲线上鲍尔点的产生条件，提出等边机构的对称连杆曲线上有单鲍尔点和双鲍尔点。

The factory affiliated to the Group primarily manufactures multiple-purpose pincers, baking kits, knives, scissors, kitchenware, gardening tools and beauty care kits as well as other hardware tools, the annual production value of which reaches US$ 30 million dollars.

集团所属工厂主要生产多用钳、烤具、刀具、剪刀、厨具、花园工具、美容套等五金产品，年生产总值3000万美元，产品价廉物美、选料上乘、质量保证，深受国内外客户的青睐