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翻譯:The need for a greater understanding of the pumping process and for the ability to engineer pump installations to a close degree of tolerance is being accentuated by the trend to pump from greater and greater depths . Problems are relatively minor when the pump is at 10,000 ft.
翻譯:A paraffin base crude is an oil whose chief components are paraffins, and which completely distilled, leaves a solid residue of wax. An asphalt base crude is an oil composed primarily of cyclic compounds (mostly naphthenes) which, when distilled, leaves a solid residue of asphalt. Oils which fall in the middle of these categrories are classified as mixed base.
翻譯:THE OPEC oil cartel is about to turn 40, and the mood in the run-up to the grand heads-of-state party in Venezuela in less than three weeks time is jubilant. Not quite two years ago,oil was $10 a barrel and the cartel was on the brink of collapse. Now the oil price is well above $30 a barrel, and it shows little sign of coming down.
翻譯:Meanahile ,steel pipes that would carry the oil were being developed . These were the first oil pipelines which take the advantage of the fact the oil is a liqnid. The ideas of a pipeline were not new , water has been transported through pipes for handreds of year ,The oil pipeline were not accepted without a struggle, hower.
翻譯:crude petroleum is not an equilibrium mixture, and on a geological time scale its composition is slowly changing. S.R.silverman found that heating at 121C for two weeks caused detectable changes, the low-molecular-weight components formed being isotopically lighter so far as the carbon was concerned, than the original.