问答题 翻译：Also specified in gas purchase contracts is the maximum amount of sulfur the sales gas may contain.

问答题 翻译In general, gas pipelines operate at higher pressure than crude lines; gas is moved through a gas pipeline by compressors rather than by pumps; and path of natural gas to the user is more direct.

问答题 翻译：the pressure of a gas varies inversely as its volume, with temperature being constant.