氦

Helium is the lightest rare gas.

氦是最轻的稀有气体。

Containers used for transporting liquid helium at pressures greater than 25 psig (40 psia) are required to be designed, manufactured, and tested to DOT specifications.

用于运输压力大于25 psig (40 psia)的液态氦的容器需要按照DOT规范设计、制造和检测。

Containers used for transporting liquid helium at less than 25 psig (40 psia) pressure are UN/DOT authorized containers.

用于运输压力小于25 psig (40 psia)的液态氦的容器是UN/DOT认可的容器。

Isotope geochemistry of noble gases Expounded the relations of 3 He4He ratio and the classif ication of tecto nic regions in China, the composite storage of mantle helium, the controversy of mantle methane and the gas-source rock correlation.

稀有气体同位素地球化学阐述了3He4He值与中国构造分区，幔源氦的复合成藏和幔源甲烷问题以及气源对比等3。

Welding to materials like aluminum, copper, white metal, and brass that have low melting temperatures and are easily oxidized, can be facilitated by flushing the welding spot with nitrogen, argon, helium, carbon dioxide or some similar protective gas.

焊接那些像铝、铜、白合金、黄铜这些熔点很低、易于氧化的材料，使用氮气、氩气、氦气、二氧化碳或一些类似的保护气体，吹洗焊接焊点。

A planet on the other hand is built up out of the dust that surrounds a star. When a star is formed there is still a disk of gas surrounding it. As this gas cools, it condenses and forms solid grains. These grain particles accrete into large bodies called planetesimals, which then collide and accrete to make protoplanets. These protoplanets evolve into planets like the planets in our own solar system.

行星演化与恒星不同：恒星形成之后，周边的气体尘埃云冷却之后凝结形成，成为行星雏形，众多小行星雏形聚合碰撞，演化成成熟的行星；没有内部的核聚变；质量超过木星13.6倍，就会产生核聚变，如果还未至木星86倍，尚处于棕矮星的阶段，将会向恒星演化；持久的核聚变需要足够大的质量来支撑，温度也不足支撑氢向氦的转变。

From the measured spectrum of He-like Al ions, we observed that the intensities of qr satellites were stronger than that of ijk satellites, and according to these observed satellite features, we have identified that photon ionization and photon excitation have very important effect on the ionization balance of these radiatively heated plasmas.

从测量得到的Al类氦离子发射光谱可以观察到，qr等伴线的强度明显高于ijk伴线的强度，由此可以确定出光子激发和电离过程对输运腔中等离子体的形成不可忽略。

The dry atmosphere consists almost entirely of nitrogen (78.1% volume mixing ratio) and oxygen (20.9% volume mixing ratio), together with a number of trace gases, such as argon (0.93% volume mixing ratio), helium, and radiatively active greenhouse gases such as carbon dioxide (0.035% volume mixing ratio), and ozone.

干大气几乎完全由氮（78.1%的体积混合比）和氧（20.9%的体积混合比）构成，还包括一些微量气体，如氩（0.93%的体积混合比）、氦，以及对辐射起作用的温室气体如二氧化碳（0.035%的体积混合比）和臭氧。

The neutrons are generated by bombard ing a heavy form of hydrogen, called tritium, with a lighter isotope of the gas, called deuterium. The resulting collisions create helium atoms and a stream of neutrons.

中子是通过氢的一种名叫氘的较氚轻的同位素来撞击它的一种名叫氚的重同位素而产生的，它们之间发生的碰撞创造了氦原子和中子流。

Objective To investigate the therapeutic effect of Argon-Helium cryotherapy combined with non-methylated CpG-ODN in treatment of rabbit liver cancer.

目的 探讨氩氦冷冻治疗对肝癌转移的影响及继发免疫效应的抗肿瘤效果。

With Death guitarist Schuldiner adopting vocal duties, the band made a major impact on the scene.

随着死亡的吉他手Schuldiner接受主唱的职务，乐队在现实中树立了重要的影响。

But he could still end up breakfasting on Swiss-government issue muesli because all six are accused of nicking around 45 million pounds they should have paid to FIFA.

不过他最后仍有可能沦为瑞士政府&议事餐桌&上的一道早餐，因为这所有六个人都被指控把本应支付给国际足联的大约4500万英镑骗了个精光。