Bottlenecks and the proliferation of crudes , with different physical qualities , cause headaches .
各种各样的瓶颈与质量参差不齐的原油种类的激增，带来了许多令人头痛的问题。
The canadian government has been lobbying hard against international restrictions on its tar sands fuels , which result in much greater carbon emissions than conventional crudes .
加拿大政府一直在游说国际社会放宽对它来自油砂的燃料油砂比原油导致的碳排放更多的限制。
Under china 's oil product pricing system , domestic fuel prices may be adjusted when the moving average of a basket of international crudes changes more than 4 % over a period of 22 working days .
' Brent crude has demonstrated remarkable strength since the beginning of february as asia becomes the marginal buyer of north sea and african crudes , ' mr. eagles said .
A leading benchmark crude oil produced in the united arab emirates , used in pricing sour crudes , predominantly for pricing middle east crude exports to asia .
