Engines aspirated

A fourth element is closely linked to the third a prostrate civil society that lacks the capacity to resist these plans. War, revolution, and economic collapse often radically weaken civil society as well as make the populace more receptive to a new dispensation. Late colonial rule, with its social engineering aspirations and ability to run roughshod over popular opposition, occasionally met this last condition. 

Power output is controlled, not by adjusting the quantity of fuel/air mixture as in the case of induced spark ignition engines, but in changing the flow of diesel fuel introduced in a fixed volume of air. The work required to aspirate the air is therefore considerably reduced which contributes still more to improve the efficiency at low loads. 

Air is supplied to the power cylinders by either natural air flow associated with the engine or by some external means. Engines that use no external means of air supply are termed to be naturally aspirated. Those with some external air supply are generally termed supercharged. The horsepower developed by an engine is dependent on its supply of air. The more air mass contained in a cylinder at ignition the more fuel that can be burned and the more horsepower that will be developed by the cylinder. 

Chemists and chemical engineers will need to join with experts in other disciplines to invent new ways to generate and transport energy for human use and provide for the needs and aspirations of a growing population in a sustainable manner. New ways will also be needed to minimize the energy used for human activities, including manufacturing. 

An aspiring perfumer must have a discriminating sense of smell. As well, a perfumist should obtain at least a bachelor of science degree in chemistry, or a degree in chemical engineering. There are few formal schools for perfumers, so... 

Barsic, N.J., Humke, A.L. 1981. Performance and emissions characteristics of a naturally aspirated diesel engine with vegetable oil fuels. SAE paper no. 810262. Society of Automotive Engineers, Warrendale, PA. 

I. Vacuum Aspirator. Can be water, steam or mechanical powered. You can make one out of an old air conditioning pump (like on a car engine). 

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