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引言本文的目的是测定用于真空以及制造超绝热杜瓦的某些低温绝热材料的真空性能。严格绝热的杜瓦能在大约两、三个月的时间内几乎无损耗地保存低温液体。目前,这些非标准绝热材料的出气速率还不易得到,因此,我们着手研究了绝热材料的出气速率以及它在较高温度的真空环境中所放出的气体成份。了解绝热材料所释放出的气体的性质是对绝热材料进行适当的预处理,以更好地控制材料的出气速率所必不可少的。我们在实验中用了宽75毫米,厚25微米和12微米两种辗压的带状聚脂薄膜(由印度纳希克M/S Garware塑料聚脂有限公司制造)和直径约为20厘米的圆形纤维盘。这些样品是由法国液化空气公司提供
INTRODUCTION The purpose of this paper is to determine the vacuum performance of certain low temperature thermal insulation materials used in vacuum and in the manufacture of ultra-adiabatic Dewar. The strictly adiabatic Dewar can hold cryogenic liquids with little or no loss in about two or three months. At present, the exit rates of these non-standard insulation materials are not readily available, so we set out to study the exit velocity of the insulation material and the composition of the gas it emits in a vacuum environment at a higher temperature. Knowing the nature of the gases released by the insulating material is essential for proper preconditioning of the insulating material to better control the material outgassing rate. We experimented with two rolled ribbon-shaped mylar films (made by Nakhi M / S Garware Plastic Polyester Co., Ltd. of India) of width 75 mm, thickness 25 μm and 12 μm, and a diameter of about 20 cm Round fiber dish. These samples are supplied by French Air Liquide