The researchers analyzed crude oils from different regions to compare their chemical compositions.

Global buyers and governments closely monitor Brent crude, as shifts in its price can signal broader economic trends.

The refinery adjusted its process to handle sour crude arriving from the Gulf.

Refineries preferred sweet crude because its sulfur content of less than 0.5% by weight lowered processing costs.

Local planners were concerned that the crude birth rate remained above 20 per 1,000 despite improvements in healthcare.

The country's crude death rate rose slightly last year due to the influenza outbreak.

Public health officials compared crude death rates across regions to identify where interventions were needed most.

Public health reports indicate that crude birth rates have fallen significantly in several provinces this year.

The ultra large crude carrier entered the channel cautiously, its navigational lights cutting through the fog.

The crew of the very large crude carrier secured all hatches and prepared for rough seas as the storm headed toward the gulf.