空心

In mammals, the primitive ectoderm is an epithelium of polarized cells that differentiates into all embryonic tissues.

事实上，我们的生命开始于一个细胞团，但在24小时内，一些细胞死去，而另一些形成一个空心的细胞球，这就是原始外胚层。

This study tried to select potentially the most aggressive species in hope of facilitating the making and the assessment of future conservation strategies. They include terrestrial species of Bidens pilosa var. radiata, Imperata cylindrical var. major, Brachiaria mutica, Paspalum distichum, Leucaena leucocephala and aquatic species of Egeria densa, Myriophyllum aqualicum, Eichhornia crassipes, Pistia stratiotes, Alternanthera philoxeroides.

本研究提出最具入侵潜力的外来植物，以作为未来保育策略之评估指标，主要有大花咸丰草、白茅、巴拉草、双穗雀稗、银合欢、水蕴草、粉绿狐尾藻、布袋莲、大萍、空心莲子草等。

It is an advanced welding tec hnol ogy to solve welding spatters of titanium alloy pressure vessels. Such a w elding method is held in vacuum condition and with a little argon gas through a hollow cathode to start a arc.

这是为解决钛合金容器焊接存在的飞溅问题而发明的一种先进的焊接工艺方法，在真空条件下，采用管状空心阴极，通入少量氩气，从而引燃电弧进行焊接。

The mechanical characteristics of air-core reactor under short-term current are computed and the distribution of electrodynamic forces is shown.

这种方法不需要事先指定对流系数，在空心电抗器设计开发阶段即可完成热性能分析，从而降低试验成本，缩短设计周期。

A hollow chamber whose dimensions allow the resonant oscillation of electromagnetic or acoustic waves.

一种尺度能允许电磁或声波共鸣的空心的室。

Hot press section consists of a set of the rollers, which a hollow metal drum, naiso electrothermic, temperature can be controlled automatically.

热压部分由一组滚筒组成，其中一只空心金属滚筒，内装电热管，温度可自动控制。

The main content and result of this research is as following:(1) Using Vis/NIR spectroscopy techniques differentiated the soybean seedling, Goose grass, Alligator Alternanthera and Emarginate amaranth, which are often living together in southern China.

本文的主要研究内容与结果如下：（1）采用Vis/NIR 光谱技术，区分了苗期的大豆与牛筋草、空心莲子草、凹头苋等几种南方地区常见的植物。

The water from cleaning silicon residue could be used as water-confected in refining epsom salt.

对于采用氟化物助浸所产生的氟化硅(SiF_4)气体环境问题，采用空心喷淋塔喷淋清水吸收方式处理。

In KP1 type perforated brick masonry, expansion bolt especially design for perforated brick is prefer, because it can form "self- anchor" effect and hold tightly in brick hole.

KP1型矩形条孔烧结页岩多孔砖砌体墙上应采用空心砌体专用膨胀螺栓，因其能够形成可靠的"自螺母效应"。

A three dimensional finite element model was established to simulate the forming process of titanium alloy hollow monolithic structure.

建立了钛合金空心整体结构成形过程的三维有限元模型。

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