必要条件

Therefore, a pre-requisite for Chinese to be awarded is to become an American citizen.

所以华人获得诺贝尔的必要条件是"加入美国国籍"。

In general, those investment diversities are the results of interactions of many biological traits to meet embryo and nestling development under the predation pressure and interspecies competition.

总之，如此不同的投资差异是在捕食压力和种间竞争作用下以及亲鸟为满足鸟卵胚胎和雏鸟迅速生长发育的必要条件下，各种生物学特征协调的结果。

The sustainable development of community is the prerequisite and basis of sustainable development of the whole society.

社区的可持续发展是社会可持续发展的基础和必要条件。

What's more , environmental protection is the prerequisite of the economic development.

此外，环境保护是经济发展的必要条件。

We must master the scientific method for the reason that it is a prerequisite to the study of science.

我们必须掌握科学方法，因为它是研究科学的必要条件。

You don′t have to define a primary key, but it′s usually a good idea.

定义主键并非必要条件，但通常是个不错的选择。

The influences of derivations and adjoint ideal semigroups of prime ring with characteristic 2 on the prime ring are discussed, and several sufficient conditions for the prime ring being communitive ring or S4-ring and some necessary conditions for a class of prime rings being communitive rings are obtained.

先给出了一个利用导子和理想来判断素环的可交换性结论的证明，然后讨论了特征为2的素环的导子和归联理想半群对这个素环的影响，得到了素环成为交换环或者S4-环的几个充分条件及一类素环成为交换环的必要条件。

Moreover,the necessary and sufficient condition for a net to be meta fair is simplified based on the primitively repetitive vector set of the net.

此外 ，本文通过网的本原可重复向量集化简了一个网为亚公平网的一组充分必要条件

The formation pressure and residual formation pressure have good relations with the maximum tectonic principal stress.

异常高压对油气藏的形成和保存有十分重要的作用，它是库车坳陷形成大型油气藏的必要条件。

Comparison of the results of experimental study and theoretical analyses further shows that the nesessary condition for the hydraulic fracturing of a soil is that the minor principal stress on the inner surface reaches the tensile strength of the soil under the action of water pressure.

试验研究与理论分析结果的比较进一步阐明促使土体发生水力劈裂的必要条件为在水压作用下内壁表面的最小有效主应力达到土的抗拉强度，从而指出过去采用的那些水力劈裂判断准则，如水压超过最小总主应力等等，都是不正确的。

The X-ray diffract was used to analyze the crystal structure of the composite. Results show that after the talc was treated with blend coupling agent, the crystal structure of talc changed, and effect Intercalation phenomenon.

通过X射线衍射分析可知，用混合偶联剂对滑石粉进行预处理后，滑石粉晶体结构发生改变，产生了插层现象，使PP／滑石粉复合材料为纳米复合材料。

An authentic Maui wedding might require the services of a 'kahu', which is a Hawaiian minister.

毛伊可能需要一个真实婚礼服务'kahu'，这是夏威夷部长。