Diesel engine blow-by is the leakage of combustion gases past the( ).A.oil rings onlyB.compression and scraper ringsC.cylinder liner sealingD.cylinder liner ring grooves
Diesel engine blow-by is the leakage of combustion gases past the( ).
A.oil rings only
B.compression and scraper rings
C.cylinder liner sealing
D.cylinder liner ring grooves
相关考题：
Damage to cargo caused by fumes or vapors from liquids，gases，or solids is known as ______.A.contaminationB.oxidationC.taintingD.vaporization
We packed up the things we had accumulated（积累）over the last three years.A:ate B:recentC:final D:past
根据以下材料，回答There is little debate about the firstdevelopment of the energy system of the 22nd century--that most of the energyproduced on a large scale will be in the form of electric power. Thus, most presentconcepts for major long-term energy sources (solar, geothermal, fusion) are basedupon electric power production at central plants.The second major development is thepotential use of hydrogen as both a basic fuel to replace natural gas and aspart of a general system to convert, store and transmit electric energy overlong district by fuel cells, or it could be used directly as a fuel forcommercial, industrial or transportation purposes.Although hydrogen seems likely to play amajor role in the future as a form of energy transport and storage, other processesmay also be useful. Here we note only two possibilities.Flywheels: It appears to be workable toconstruct flywheels of almost any needed size that would be efficientconverters (93-95 percent) in first storing and then releasing electric power.In addition, the kinetic (动力的) energy ofrotation is easily converted to alternating electric power. But the engineeringis at an early stage of development, and a decade or more may pass before this potentialcan be reliably estimated.Batteries and fuel cells: some of the manybatteries being developed today look quite promising. Within a decade or two, abattery-operated electric auto might even become competitive with today′ s vehicles,at least for driving ranges up to 200 miles. An electric automobile would bepollution-free,and would probably be more energy-efficient than theinternal-combustion (内燃) engine.A fuel cell (which may be considered a hydridebattery) with about 40 percent conversion efficiency is expected to enter powerproduction on a large scale within about five years. Unlike steam-poweredgenerators, fuel cells can be made large or small and their efficiency inoperation is essentially independent of the loading. Thus they may avoid mostof the distribution costs of electric power as well as provide pollution-fleepower and offer opportunities for using the "waste heat" effectively.From the passage we can see that thefuel cell might be something ___________.A.with the electric energy stored in itwithout pollutionB.in which chemicals are containedC.in which certain fuels such as hydrogenare filledD.like a small steam generator
根据以下材料，回答There is little debate about the firstdevelopment of the energy system of the 22nd century--that most of the energyproduced on a large scale will be in the form of electric power. Thus, most presentconcepts for major long-term energy sources (solar, geothermal, fusion) are basedupon electric power production at central plants.The second major development is thepotential use of hydrogen as both a basic fuel to replace natural gas and aspart of a general system to convert, store and transmit electric energy overlong district by fuel cells, or it could be used directly as a fuel forcommercial, industrial or transportation purposes.Although hydrogen seems likely to play amajor role in the future as a form of energy transport and storage, other processesmay also be useful. Here we note only two possibilities.Flywheels: It appears to be workable toconstruct flywheels of almost any needed size that would be efficientconverters (93-95 percent) in first storing and then releasing electric power.In addition, the kinetic (动力的) energy ofrotation is easily converted to alternating electric power. But the engineeringis at an early stage of development, and a decade or more may pass before this potentialcan be reliably estimated.Batteries and fuel cells: some of the manybatteries being developed today look quite promising. Within a decade or two, abattery-operated electric auto might even become competitive with today′ s vehicles,at least for driving ranges up to 200 miles. An electric automobile would bepollution-free,and would probably be more energy-efficient than theinternal-combustion (内燃) engine.A fuel cell (which may be considered a hydridebattery) with about 40 percent conversion efficiency is expected to enter powerproduction on a large scale within about five years. Unlike steam-poweredgenerators, fuel cells can be made large or small and their efficiency inoperation is essentially independent of the loading. Thus they may avoid mostof the distribution costs of electric power as well as provide pollution-fleepower and offer opportunities for using the "waste heat" effectively.In which of the following is the use ofthe "waste heat" mentioned?A.The fuel cell.B.The fly wheel.C.The steam-powered generator.D.The internal-combustion engine.
根据以下材料，回答There is little debate about the firstdevelopment of the energy system of the 22nd century--that most of the energyproduced on a large scale will be in the form of electric power. Thus, most presentconcepts for major long-term energy sources (solar, geothermal, fusion) are basedupon electric power production at central plants.The second major development is thepotential use of hydrogen as both a basic fuel to replace natural gas and aspart of a general system to convert, store and transmit electric energy overlong district by fuel cells, or it could be used directly as a fuel forcommercial, industrial or transportation purposes.Although hydrogen seems likely to play amajor role in the future as a form of energy transport and storage, other processesmay also be useful. Here we note only two possibilities.Flywheels: It appears to be workable toconstruct flywheels of almost any needed size that would be efficientconverters (93-95 percent) in first storing and then releasing electric power.In addition, the kinetic (动力的) energy ofrotation is easily converted to alternating electric power. But the engineeringis at an early stage of development, and a decade or more may pass before this potentialcan be reliably estimated.Batteries and fuel cells: some of the manybatteries being developed today look quite promising. Within a decade or two, abattery-operated electric auto might even become competitive with today′ s vehicles,at least for driving ranges up to 200 miles. An electric automobile would bepollution-free,and would probably be more energy-efficient than theinternal-combustion (内燃) engine.A fuel cell (which may be considered a hydridebattery) with about 40 percent conversion efficiency is expected to enter powerproduction on a large scale within about five years. Unlike steam-poweredgenerators, fuel cells can be made large or small and their efficiency inoperation is essentially independent of the loading. Thus they may avoid mostof the distribution costs of electric power as well as provide pollution-fleepower and offer opportunities for using the "waste heat" effectively.The energy we use most todayis___________A.solar energy B.geothermal energyC.hydrogen D.electricity
柴油机的燃料“Diesel”是以发明人名字命名的