worldly
poisonous
wholesome
void
第1题:
Passage Five
From the beginning rivers have played an important part in the life of man. Man of the earliest times used the rivers as a means of traveling. Today rivers still serve as a great waterway for the transport and people.
In ancient times, man settled near rivers or on river banks and built up large empires.
Water is the Nature's most precious gift to man. Man needs water to irrigate his crops, to cook and to wash. In nations all over the world rivers mean life and wealth. They feed and clothe the nations around them.
Water is also a source of energy and power. Man constructs huge dams across the river to control the water for irrigation and get the energy needed to drive generators. The electrical power is then directed to homes, cities, factories and television stations.
Man uses water each day. His main source of water comes from reservoirs, which in turn get their water from the rivers.
Rivers also bring down soil and minerals from the mountains and deposit them on the plains building up rich river deltas for raising plants and crops. Fresh water life in rivers or in lakes fed by them provide man with food.
In a small way rivers help to keep man in good health and provide for his amusements. Various forms of water sports keep man strong and healthy.
Rivers have run on this earth long before man. Man's future ability to live is uncertain, but rivers will flow on forever.
52. Rivers have been important to man______.
A. since the last century
B. for a very long time
C. since a few hundred years ago
D. since a few years ago
第2题:
In an auxiliary diesel engine bypass type lubricating oil system, the main lube oil pump forces_______ .
A.all of the oil used by the engine through a filter
B.some of the oil used by the engine through a filter
C.some of the oil used by the engine through a centrifuge
D.all of the oil used by the engine through a centrifuge
第3题:
Before loading bulk grain, bilge wells must be covered to ______.
A.add strength to the bilge well strainer
B.permit rapid flow of water to the bilge wells
C.prevent cargo sifting into the bilge wells
D.prevent oil, water, or other liquid from reaching the cargo
第4题:
第5题:
第6题:
The supply chain activities encompass all associated with the flow and transaction of goods, the flow of information from the raw materials supplier to the end user, as well as the reverse flow of materials and in formation in the()
第7题:
add strength to the bilge well strainer
permit rapid flow of water to the bilge wells
prevent cargo sifting into the bilge wells
preven oil, water , or other liquid from reaching the cargo
第8题:
seal water supply be cut off
make-up water supply be cut off
oil outlet valve closed or not open sufficiently
the flow rate of oil is too much
第9题:
Place the eye from the forward line on the bollard and then place the eye from the second line directly over the first
It makes no difference how the lines are placed
Place the eye from either line on the bollard,and then bring the eye of the other line up through the eye of the first,and place it on the bollard
Place both eyes on the bollard,in any manner,but lead both lines to the same winch head on the vessel and secure them on the winch
第10题:
stop the flow of oil at the main deck manifold
prevent the oil from leaving the shore facility
prevent the oil from siphoning through the pump
None of the above
第11题:
contaminated
emulsified
deteriorated
oxidated
第12题:
it also would be rendering the earth uninhabitable
rendering the earth uninhabitable
might have uninhabitably rendered the earth
render the earth uninhabitable
would also have rendered the earth uninhabitable
第13题:
第二组
Displacement pumps are those where the volume of the pump chamber is alternately increased to draw the liquid in from the suction pipe and then decreased to force the liquid out into the delivery pipe. Centrifugal pumps are those wherein an impeller rotating at high speed throws the liquid by centrifugal force from the center to the periphery of the impeller where the liquid is discharged through the delivery outlet.
Gear pump consists of two or more meshing gears (spur, single or double helical teeth) enclosed m a close-fitted housing. These are used extensively for pumping fuel oil, lubricating oil and hydraulic oil. When gears are unmeshed on the inlet side, a pressure drop occurs that helps the atmospheric pressure acting on the surface of the oil in the reservoir to force it up the pipe to fill the void, the oil is then transferred around the periphery of the pump housing. As the gear teeth mesh again on the outlet side, they form. a seal that prevents oil from backing up to the inlet, the oil in the void is then be forced out into the discharge line.
All vane pumps have a rotor driven within a ring (cam ring) by a drive shaft coupled to a prime mover. A cylindrical rotor with sliding vanes, generally in radial slots, rotates within the ring. The center of the rotor is offset from the center of the ring. In a simple vane pump, as the rotor turns, the vanes are forced outward against the inner surface of the cam ring by centrifugal force. This outward radial movement of the vanes and turning of the rotor causes the chamber between the vanes to increase as the vanes pass further away from the inlet port. This increase in volume results in a lowering of pressure until the atmospheric pressure is sufficient to force oil from the reservoir into the inlet chamber. Oil from the inlet is swept away by the vanes toward the outlet port through a decreasing series of chambers until it is forced through the outlet port. A vane pump of balanced design has an elliptical cam ring so that two pumping chambers are formed. This pump is in hydraulically balance, since the two intake and two outlet ports are diametrically opposed to each other. Therefore the side loads exerted on the rotor cancel out, thereby increasing bearing lift and permitting high operating pressure.
According to the last sentence of paragraph 1, from where the liquid is discharged through the delivery outlet?
A.from the eye of the impeller
B.from passage of impeller
C.from the periphery of the impeller
D.from the impeller
第14题:
An uncontrolled flow of gas, oil, or other well fluids into the atmosphere is called a ______.
A.flow
B.breakout
C.kick
D.Blowout
第15题:
第16题:
第17题:
第18题:
flow
breakout
kick
blowout
第19题:
Distribution process
Supply chain
Enterprise
International community
第20题:
bilge tank
sludge tank
overflow tank
oil collecting tank
第21题:
stop the flow of oil at the main deck manifold
prevent the oil from leaving the shore facility
prevent the oil from siphoning through the pump
None of the above
第22题:
第23题:
build big lakes to store water
construct big pumping stations
channel water from nearby rivers to cropland
build small and cheap irrigation systems