必要条件

According to the thermodynamics,it was discussed the possibility of reduction of sodium metaborate to produce sodium borohydride.

首先从热力学角度讨论偏硼酸钠还原生成硼氢化钠的反应；根据吉布斯函数，讨论反应进行的必要条件。

The structual evolution, depositional system, coal-derived hydrocarbon, good reservoir, crack pathway, migrational direction, and heat source are all the principal factors of the formation of the petroleum systems in this area.

盆地构造演化、沉积体系、煤成烃、优质储层、裂缝通道、运移方向、热来源等都是该区油气系统形成的必要条件和基础。

A requirement for the survival of a learning com?munity is the freedom to exercise power for/with/through opportunities and resources.

一个学习共同体要想生存下去，一个必要条件就是拥有行使权力的自由。

For a class of nondifferentiable generalized fractional programming problems with the norm \$‖Bx‖\-p\$ in the objective function involving, a new incomplete Lagrange function is given, and the saddle point optimal criteria are proven by using the existing necessary optimality conditions, under the assumptions of the class of generalized (\$F,α,ρ,d\$)-convexity.

对于一类目标函数中含范数‖Bx‖p的非可微广义分式规划，给出了一个新的非完全Lagrange函数，并利用已有的最优性必要条件，在一类广义-凸性的条件下，证明了鞍点最优性准则。

In this part, the article first elaborates the definition of shareholder and the qualification of shareholder. Then this article analyzes the differences between internal and external transfer of shares. Having analyzed the nature of shareholder's right, this article proposes that there exist obligational and property act in the transfer of shares and the share transfer contract is only necessary condition for the change of shareholder qualification.

本部分在阐述股东与股东资格概念（实质要件说、形式要件说）的基础上，对股权的内部转让与外部转让对股东资格认定的不同影响进行了分析，并结合股权法律关系即股权的权利属性的探讨，重点论述了股权转让过程中的债权行为（股权转让合同的签署与生效）与物权行为（股权转让合同的履行，即股权实际变动），认为股权转让合同的生效只是股东资格变动的必要条件而非充要条件。

It is not the memory but the oblivescence that is one of the necessity for survival.

不是记忆力，恰恰相反，是遗忘构成了我们赖以生存的必要条件之一。

In the second part, necessary and sufficient conditions are derived for complete reachability and observability of periodic time-varying descriptor systems.

在第二部分中，我们先针对周期奇异系统的完全可达性与完成可观性，给出一系列的充分必要条件。

The analyses of the meterological and oceanographical data from seriel observations aboard R/V Xiangyanghong 5 during the voyage of joint AMEX experiment by Australia,China and the United States show that (1) there is high level of humidity within middle and low layers of troposphere at the initial stage of a typhoon's formation,and once a typhoon has fully developed,the highest level of humidity remains within middle layer of tropisphere;(2) although small vertical wind shear is a requisition for a t...

对中、美、澳三国AMEX试验期间&向阳红5号&定点观测到的气象和海洋资料分析得出：①台风形成前，大气整个中、低层空气湿度较大，台风一旦形成，大气湿度最大层主要集中在中空；②风速垂直切变小，对形成台风是一个必要条件，但并非整个对流层风速切变都小，而且不同地区形成的台风，风速切变状况是不同的；③厄尔尼诺年南半球与北半球对应位置同期的θ_G、θ_8、Q_b相差不大，但是南半球的θ_c较北半球的大。

Sufficient pathogen, susceptible host and favourable environmental conditions,which are necessary to the outbreaking of the plant disease.

一定数量的病原生物、易感病的寄主以及有利的发病条件是任何病原生物引起的植物病害发生的必要条件。

Palaeogeographic database can be established with various information acquisition and management methods. Palaeogeographic information of multi-source and multiscale can be organized with a spatial data model. Palaeogeographic environments can be reconstructed with the 3D modeling and a virtual reality technique. Palaeogeographic research achievements can also offer better service with the development of internet technology.

多种多样的信息采集和管理方法可以建立不同时期的古地理学综合数据库；空间数据模型为组织多来源和多尺度的古地理信息提供框架；三维数据建模和虚拟现实技术为古地理环境重建营造了必要条件；互联网技术的发展可使古地理学研究成果更好地为用户服务。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。