液氦

要走第三步，达到液氦的温度4°K需要十分精湛的技术。

Real ingenuity is required to take the third step to attain liquid helium temperatures of 4 ° K.

对于海外运输，液氦ISO罐可以从拖车底座上移动下来。

Liquid helium ISO tanks may be removed from the trailer chassis for overseas shipments .

EAST超导托卡马克热负荷波动对低温系统液氦槽的影响

Effect on pressure in the vessels of EAST cryogenic system due to fluctuation of heat loads

针对研制的一种蓄冷器外置型式的液氦温区G－M制冷机进行了实验研究。

An experimental study on a two-stage G-M refrigerator operating in the liquid helium temperature region with the cold regenerator outside of the displacer has been studied .

直接达到液氦温度的G-M型制冷机及其应用

G-M refrigerator operating at liquid helium temperature and its application

NBI低温冷凝泵液氦杜瓦的热力分析与工程设计

Thermal analysis and engineering design for liquid helium Dewar of NBI cryocondensation pump

一种蓄冷器外置的液氦温区G-M制冷机的实验研究

An Experimental Study on a 4.2K G-M Refrigerator with Regenerator outside of Cylinder

用大型软件Fluent对液氦杜瓦的温度分布并用ANSYS对磁体磁场分布进行了数值模拟。

The commercial software Fluent is used to simulate the temperature distribution of liquid helium dewar and ANSYS is used to simulate the distribution of magnetic field .

液氦温区双级G-M制冷机循环的数值模拟分析

Numerical Simulation and Analysis on GM Refrigerator Working in the Liquid Helium Temperature Region

实验还表明Kink大小是液氮下比室温下大、液氦下比液氮下的大。

The Kink size is larger at LN than at RT and larger at LHe than at LN .

BEPCⅡ超导腔液氦控制杜瓦非稳态供液过程的建模及仿真

Modelling and Simulating on the Liquid Helium Discharge Process from Dewar of SRF Cooling System in BEPC ⅱ

液氦温区G-M制冷机蓄冷器工作过程探讨与分析

The Discussion and Analysis on the Working Processes of the Regenerator of G-M Refrigerator at Liquid-helium Temperature

EAST装置于2006年成功进行工程调试和物理实验，全部超导磁体均已冷却到液氦温度，并获得了第一次等离子体。

EAST ( Experimental Advanced Super-conducting Tokamak ) is an experimental device for controlling nuclear fusion . In 2006 , the engineering commissioning of EAST has already been done successfully . All of the superconducting magnets have been cooled down to LHe temperature .

结论幼鼠早期液氦损伤可导致小脑回形成及海马CA3区苔藓纤维发芽。

Conclusion Neonatal liquid nitrogen injury could result in mossy fiber sprouting in hippocampal CA3 region and microgyrus .

在室温、液氮和液氦温度下，首次用连续调谐的CO2激光器研究了n-InSb自由载流子法拉第旋转。

The free carrier Faraday rotation in n-InSb has been studied by using a tunable CWCO_2 laser for the first time at room temperature , liquid nitrogen and liquid helium tempe-rature .

极为敏感的探头是一个超导量子介入装置（SQUID），它在低温保持器中使用液氦冷却（-269℃），能够以二维分辨率探测和量化非常微弱的磁信号。

Extremely sensitive sensors , Superconductive Quantum Interference Device ( SQUID ), cooled in a cryostat with liquid helium ( - 269 ℃), can detect and quantify the very weak magnetic signals with 2 dimensional resolution .

本文介绍了用于SQUID测量的10升玻璃钢液氦杜瓦，内胆用DB1低温玻璃钢制作，杜瓦外壳采用环氧聚酰胺玻璃钢制造。

This paper describes a ten-liters fiberglass reinforced plastic ( FRP ) liquid-helium dewar , which is prepared for SQUID . The inter container is made of DB-1 cryogenic FRP , and the outer case of this dewar is made of epoxy-polyamide FRP .

为检验我们所提出的一种高电流密度超导磁体的新设计原则，即采用涂漆导线与层间窄液氦通道的可行性与优越性，设计与建造了内径20cm的超导螺管。

To examine the mew design principle using vanish-coated conductor and narrow helium channels between layers for high current density magnets , a solenoid with 20 cm inner diameter has been designed and constructed .

研究发现，通过脉管冷端换热器的结构改进，液氦温区脉管制冷机在4.2K温区的制冷量可以得到显著提高。

The cooling performance of the 4 K pulse tube cooler ( PTC ) can be greatly improved by the modification of the structure cold end heat exchanger .

大型强子对撞机（LHC）是新一代加速器的代表，为了达到所需力场，该加速器中的磁体必须采用液氦进行冷却。

Large Hadron Collider ( LHC ) is the representative of a new generation of accelerators , in order to achieve the required force field of the accelerator 's magnets must be cooled using liquid helium .

在LHC可以启动前，必须将其5万吨设备用超流体液氦冷却至绝对零度之上仅1.8K的温度，这是迄今为止历史上最大的低温工程。

Before the LHC can start , 50,000 tonnes of equipment have to be cooled to just 1.8 ? Kelvin above absolute zero with superfluid liquid helium – by far the largest cryogenic project in history .

为此，在NBI系统漂移管道内放置了一台液氦低温冷凝泵，以冷凝束流中的氢及氢的同位素来保持动态高真空。

Therefore , a low temperature liquid helium vapour pump has been laid within the drift pipe of the NBI system to maintain continual vacuum by using the condensation of hydrogen and its isotope in the beam .

试验结果：系统灌注液氦平衡后，连续16个小时液氦的平均蒸发量为1.1升/小时，磁体系统磁场强度大于5T，基本满足用户的使用要求。

Tests results : The performances are vapor rate of liquid helium is 1 . 1 liter / hour in 16 hour . magnetic field strength is up to 5T . It will meet user 's requires .

在内杜瓦瓶温度～70K、场强为10T时，液氦蒸发率为1.3&1.6升/小时之间。

At 10T field strengh , when the temperature in the inner dewar is at 70 K , the loss rate is in the range of 1.3-1.6 liters per hour .

用绝热法测量了YBa＿2Cu＿3O＿（7－δ）高温超导体的比热，介绍了测量方法和测量装置，并给出了在液氦77～110K温度区所测比热的结果。

The specific heat measurement of YBa_2Cu_3O_ ( 7 - δ) superconductors are introduced . With our experience for the specific measurement for YBa_2Cu_3O_ ( 7 - δ) superconductore , the measuring adiabatic calorimetry method are discussed .

经过优化，设计了一台可工作于液氦温区的三级脉冲管制冷机，其最低制冷温度可达3.9K，为实验研究奠定了理论基础。

After optimization , a three-stage pulse tube refrigerator working at the liquid helium temperature was designed . Its lowest cooling temperature without cooling load reached 3.9K .

用量子力学修正的WCA液体变分微扰理论计算了液氦冲击压缩曲线，计算中体系分子间相互作用势选择EXP6有效两体势模型，两体势参数通过对实验数据的拟和优选。

For liquid helium , the modified WCA liquid perturbation theory was used to calculate Hugoniot curve using EXP-6 reference potential . The theory is generalized to include quantum effects by adding the first term of Wigner-Kirkwood expansion .

为了满足液氦温区分离型二级脉管制冷机第二级预冷的需要，设计制作了1台20～40K温区单级大功率脉管制冷机。

A single-stage and high power pulse tube cooler working between 20 ~ 40 K has been designed and constructed in order to precool the second stage of a 4 K separate two-stage pulse tube cooler .

测量了Zr41Ti14Cu12.5Ni10Be22.5大块非晶及不同退火条件的样品在液氦温区的比热.而超导磁体大都运行在约4.5K（-269℃）的液氦温区，这又促进了低温技术的发展。

Specific heat of the bulk amorphous Zr-Ti-Cu-Ni-Be alloy and different heat-treated samples has been measured in temperature range from 4.5 to 30K . Cryogenic technology is developing with the requirement of operation for superconducting magnets .

低温液氦或液氮气化到室温环境后体积将膨胀700（LN2）的780倍（LHe），不加控制低温气体泄漏到房间中会引起氧气缺乏事故。

Liquid nitrogen or helium can expand by factors of 700 ( LN2 ) or 780 ( LHe ) to normal temperature , and the uncontrolled releasing into an enclosed space can cause on oxygen deficiency hazard ( ODH ) .