冷头

GE1.5T磁共振机冷头的相关故障

Malfunction related to Cold Head of GE1.5T MR Machine

超导型磁共振冷头的工作原理及维护保养

Principle and maintenance of the cold head in superconductive MRI

基于能量守恒原理，从试验数据中提取了G-M冷头动态模型。

The dynamic model of the G-M heat exchangers were obtained from the experimental data based on the energy conversation .

给出了不同运行电流下，在室温温度（300K）和制冷机一级冷头温度（77K）间铜电流引线的温度、热流分布。

The temperature distribution and thermal flux distribution of copper lead were also given in range of room temperature ( 300 K ) to one stage of refrigerator temperature ( 77 K ) at different operating currents .

根据扫描图像准确地计算冷头进入方向与距离。

Direction and distance could be calculated according to scanning images .

导出具有传热热阻，内部摩擦和冷头热漏不可逆损失的不可逆卡诺制冷机的最大制冷系数。

The maximum refrigeration coefficient of an irreversible Carnot refrigerator is derived .

本文着重介绍冷头的工作原理、运行方式及其在使用中的日常维护和定期保养。

This article focuses on the principle , operation and maintenance about the cold head .

具有外热阻内摩擦和冷头热漏制冷机的最大制冷系数

The Maximum Refrigeration coefficient of a Refrigerator with External Heat Resistance , Internal Friction , Cold End Heat Leak

降低高温超导电流引线向低温环境的漏热，以及实现电流引线与制冷机冷头导热不导电的直接接触冷却，是制冷机直接冷却超导系统走向应用的关键技术之一。

Reducing the heat leak to the low temperature environment and gas free cooling HTSC current lend are very important for the application of GM cooler conduction cooling superconductor system .

采用有限时间热力学研究了传热热阻，内部摩擦和冷头热漏三种不可逆损失对制冷机最优性能的影响。

Using finite-time thermodynamics , it is investigated that the optimal function of a refrigerator is affected by three kinds of irreversible of heat resistance , internal friction and cold end heat leak .

尽量避免冷油头出站，防止中间冷油掺入。

Prevents cold oil head from outgoing of the station and avoids cold oil mixing up ;

有部分转出方基于担心削弱自身经济实力等原因导致的观望情绪，双转移中存在一头冷一头热现象。

There are parts of the transferor sentiment based on fear weaken its economic strength and other causes .

目的评价药棉液氮浸冷冷冻头冷凝视网膜裂孔的安全性和疗效。

Objective To evaluate cryotherapy safety and effect of liquid nitrogen cooled cotton cryoprobe on seal retinal tears .

介绍了一种在无冷柱头进样器和特殊注射器情况下简便可行的冷柱头进样技术。

A simple and convenient cold on-column injection method was introduced for capillary gas chromatograph with no special injector .

药棉浸冷冷冻头冷凝视网膜裂孔临床实验研究

Head continuous with body ; Clinical and experimental studies on seal retinal tears by cotton cryoprobe cooled liquid nitrogen

采用冷柱头进样的高温气相色谱技术，建立了测定高滴熔点微晶蜡中正构和非正构烃类含量及碳数分布的方法。

A method has been developed to measure the carbon distribution and content of microcrystal wax with high drop melting point .

加剂低输量管道存在着加剂站出站管道防腐层老化、中间加热站加热炉对流管的低温腐蚀、加剂后冷油头引起输油干线压力升高等问题。

There are such problems existing in depressant low throughput pipeline as coating aging in outgoing line at depressant station , low temperature corrosion of convection coils in heater at intermediate heating station , pressure rising in trunk-line caused by cold oil head .

双相不锈钢空冷器管头自动氩弧焊焊接工艺

Welding Technology of Duplex Stainless Steel Air-cooler 's Shoe Automatic Argon Arc Welding

定性的讨论了挤压次数及材料力学性能对冷压焊接头性能的综合影响。

Integrated influence of extrusion times and metal 's mechanical property to quality of cold pressure welding joint was discussed .

介绍冷铸镦头锚的构造，给出了主要技术要求。

The construction of cold casting heading anchor is introduced , and the main technology requirements of the construction are given .

本文还对实行过热时效的各种冷压焊接头界面原子扩散行为进行了测定，揭示出它们的扩散规律。

This paper also measured the diffusing action of atoms at interface of various cold-pressure welded joints after ageing super-heating and found its rule of diffusion .

介绍了矿用帆布胶带冷补粘结头的制作方法及对接头的日常检查和维护所要做的工作。

In the same time it is propitious to its check up and its maintenance . The paper introduces way of making common canvas belt bond joints and the daily maitenance .

从电磁动态技术、内冷系统、模头、螺杆各个方面重点阐述了茂金属聚烯烃新型成型技术及其装备。

We focus on describing the new processing technology of metallocene polyolefins and it 's equipment in the aspects of the electro magnetic dynamic technology , internal cooling system , mold and screw .

采用冷溶剂提取新鲜大蒜中的有机硫化合物，结合冷柱头程序升温进样，对大蒜原始组分进行了气相色谱/质谱分析。

For the analysis of organosulfur compounds in fresh garlic , a gas chromatographic / mass spectrometric ( GC / MS ) method is proposed using temperature-programmable cold on-column injection and cold solvent extraction of the fresh garlic .