查询词典 molecule

In the single crystal of C60 with a FCC structure,positron mainly appears outside the C60 molecule.The main annihilation space is the interspace between molecules.The calculated positron bulk lifetime in C60 is 352ps, which agrees with experiment value of 356ps in literature.In carbon nanotube bundles with different dimeters,as the diameter of carbon nanotubes increases,the main space where positron appears changes from the interspace of carbon tubes to the space inside carbon tubes,the radio between positron annihilation with valence eletrons and core eletrons becomes larger,the positron bulk lifetime in carbon nanotube increase rapidly first and come to be a constant at the end.The calculated positron lifetime of carbon nanotube with a dimeter of 0.8～1.6ns is 332～470ps,which agrees with the experiment value of 394ps.Positron annihilation has been studied in widly used compound semiconductors.

计算结果表明：在片层结构的石墨晶体中，正电子主要在石墨层间的空隙中湮没，计算出的石墨中的正电子寿命为208 pS，与文献中的实验结果215 ps符合很好；在金刚石单晶中，正电子主要在碳原子之间的空隙中存在并发生湮没，计算出的金刚石中的正电子寿命为115 ps，文献中的实验结果110 ps左右符合；在面心立方结构的C60晶体中，正电子主要在C60分子球壳内外侧及分子之间存在，C60球形分子中心正电子分布很少，正电子的湮没区域集中在C60分子之间的空隙区域，计算出的C60中的正电子寿命为352 ps与文献中的实验结果356ps相符合；对于不同管径碳米管束中的正电子分布，随着碳纳米管直径的增加，碳纳米管束中的正电子由主要在碳纳米管管间的区域出现转变为主要在碳纳米管管内中心的区域出现：碳纳米管束中的正电子与碳原子的价电子的湮没概率变得越来越大，与核心电子的湮没概率变得越来越小；碳纳米管束中正电子的湮没寿命先迅速增大，而后趋于一定值。

Dip Pen NanolithographyTM is a nanoscate patterning technique in which a microfabricated probe with a molecule-coated, sharpened tip delivers molecules while in contact with and translated across a sample substrate.

蘸水笔纳米印刷术是通过一个携带涂敷分子的微修饰探针的尖锐笔尖将分子通过接触传递到样品底物上去的一种纳米图形技术。

Chlorine is used to disinfect pool water because it's a very reactive molecule and it combines with organic compounds.

氯是给池水消毒用的因为它是一种活性非常强的分子并且它与有机化合物进行反应。

The applied effect of nanometer material mainly depend on surface molecule design of nano-powder material and its dispersion degree in matrix, i. e., how to disperse nano-particles into polymer matrix on nano-scale level.

因此，纳米材料的应用功效主要取决于纳米粉体材料的表面分子设计（即与基体材料的相容性问题）及其在基体材料中的分散度，也就是如何将纳米粒子以纳米尺度分散于高分子基体中。

In the second part,theoretical research on the dissociation process of NaI molecule is carried out.

在第二部分中我们从理论上对NaI分子的光解离过程进行了研究。

Goldberg got a class of polyhedra which are icosahedral symmetry by appending hexagons on regular dodecahedron by rule in 1937. They are called Goldberg polyhedra which provides a new approach for polyhedral molecule design.

1937年，数学家Goldberg通过在正十二面体上有规律地添加六边形面得到一类具有二十面体对称性的多面体，即Goldberg多面体。

This illness is caused by low levels of a messenger molecule called dopamine in certain parts of the brain.

这种疾病是由大脑某一区域低水平的多巴胺信使分子引起的。

The results showed that the double bond in the molecule played animportant role to the cytotoxicity.

结果表明，此类化合物的细胞毒性与其分子中双键存在与否有着重要的关系。

Lyase An enzyme that catalyzes the separation of two parts of a molecule with the formation of a double bond in one of them.

裂解酶：一类能催化一个分子的两部分分离，并在其中一个上形成双键的酶。

But this molecular model shows how some proteins form loops in DNA when they chemically attach, or bind, at separate sites to the double-helical molecule that carries life's genetic blueprint.

就像槲寄生包绕在柔软的甘蔗蔓藤上，分子模型展示了某些蛋白在DNA 如何形成环状，当它们用化学键贴或者绑在携带生命遗传蓝图的双螺旋DNA分子。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。