The cooling medium, or coolant, in them is either water or some low-freezing liquid, called antifreeze. 冷却介质,或冷却剂,在他们要么水或一些低冷冻液,所谓的防冻剂。
3973 amorphous hydrocracking catalyst was developed for maximum yield of low-freezing diesel, with appropriate activity, high liquid yield, high selectivity to middle distillates, good stability and low freezing-point of the diesel oil product. 3973催化剂是为满足最大量增产优质低凝柴油的需要而开发的一种单段无定形加氢裂化催化剂,具有活性适宜、液体收率和中油选择性高、稳定性好及柴油产品凝点低等特点。