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单选题
What DOCS SALT WATER DRAFT means?（）.
A
It means summer draft
B
It means Maximum draft
C
It means Fresh Water draft
D
It means Seawater Draft
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更多 “单选题What DOCS SALT WATER DRAFT means?（）.A It means summer draftB It means Maximum draftC It means Fresh Water draftD It means Seawater Draft” 相关考题
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The water in an auxiliary boiler should be tested for chloride content to determine ( ).A.total dissolved solidsB.salt contaminationC.water harcnessD.chlorine contamination
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What is the BEST conductor of electricity?A.Carbon dioxideB.Distilled waterC.Fresh waterD.Salt water
考题
______is the number of millimeters by which the mean draft changes when a ship passes from salt water to fresh water，or vice versa，whilst floating at the loaded draft．A.TPCB.The Fresh Water AllowanceC.Parallel sinking of the shipD.UKC
考题
Heat exhaustion is caused by excessive ______.A.loss of body temperatureB.loss of water and salt from the bodyC.gain in body temperatureD.intake of water when working or exercising
考题
请阅读短文，完成此题。
When we analyze the salt salinity(盐溶度 ) of ocean waters, we find that it varies only slightly from place to place. Nevertheless, some of these small changes are important. There are three basic processes that cause a change in oceanic salinity. One of these is the subtraction of water from the ocean by means of evaporation. In this manner, the salinity is increased, since the salt stays behind. If this is carried to the extreme, of course, white salt would be left behind; this, by the way, is how much of the table salt we use is actually obtained.
The opposite of evaporation is precipitation, such as rain, by which water is added to the ocean. Here the ocean is being diluted so that the salinity is decreased. This may occur in areas of
high rainfall or in coastal regions where rivers flow into the ocean. Thus salinity may be increased by the subtraction of water by-evaporation, or decreased by the addition of fresh water by precipitation.
Normally, in hot regions where the sun is very strong, the ocean salinity is somewhat higher than it is in other parts of the world where there is not as much evaporation. Similarly, in coastal regions where rivers dilute the sea, salinity is somewhat lower than in other oceanic areas.
A third process by which salinity may be altered is associated with the formation and melting of sea ice. When seawater is frozen, the dissolved materials are left behind. In this manner, seawater directly beneath freshly formed sea ice has a higher salinity than it did before the ice appeared. Of course, when this ice melts, it will tend to decrease the salinity of the surrounding water.
In the Weddell Sea, the densest water in the ocean is formed as a result of this freezing process, which increases the salinity of cold water. This heavy water sinks and is found in the deeper portion of the oceans of the world.
The purpose of mentioning the Weddell Sea is__________.
查看材料
A．to give an example of cold-water salinity
B．to point out the location of deep waters
C．to make a comparison between hot-water salinity and cold-water salinity
D．to show that the water in the Weddell Sea varies in salinity from place to place
考题
请阅读短文，完成此题。
When we analyze the salt salinity(盐溶度 ) of ocean waters, we find that it varies only slightly from place to place. Nevertheless, some of these small changes are important. There are three basic processes that cause a change in oceanic salinity. One of these is the subtraction of water from the ocean by means of evaporation. In this manner, the salinity is increased, since the salt stays behind. If this is carried to the extreme, of course, white salt would be left behind; this, by the way, is how much of the table salt we use is actually obtained.
The opposite of evaporation is precipitation, such as rain, by which water is added to the ocean. Here the ocean is being diluted so that the salinity is decreased. This may occur in areas of
high rainfall or in coastal regions where rivers flow into the ocean. Thus salinity may be increased by the subtraction of water by-evaporation, or decreased by the addition of fresh water by precipitation.
Normally, in hot regions where the sun is very strong, the ocean salinity is somewhat higher than it is in other parts of the world where there is not as much evaporation. Similarly, in coastal regions where rivers dilute the sea, salinity is somewhat lower than in other oceanic areas.
A third process by which salinity may be altered is associated with the formation and melting of sea ice. When seawater is frozen, the dissolved materials are left behind. In this manner, seawater directly beneath freshly formed sea ice has a higher salinity than it did before the ice appeared. Of course, when this ice melts, it will tend to decrease the salinity of the surrounding water.
In the Weddell Sea, the densest water in the ocean is formed as a result of this freezing process, which increases the salinity of cold water. This heavy water sinks and is found in the deeper portion of the oceans of the world.
It can be known from the passage that increase in the salinity of ocean water is caused by__________.
查看材料A．melting of sea ice
B．precipitation
C．evaporation
D．supplement of salt
考题
请阅读短文，完成此题。
When we analyze the salt salinity(盐溶度 ) of ocean waters, we find that it varies only slightly from place to place. Nevertheless, some of these small changes are important. There are three basic processes that cause a change in oceanic salinity. One of these is the subtraction of water from the ocean by means of evaporation. In this manner, the salinity is increased, since the salt stays behind. If this is carried to the extreme, of course, white salt would be left behind; this, by the way, is how much of the table salt we use is actually obtained.
The opposite of evaporation is precipitation, such as rain, by which water is added to the ocean. Here the ocean is being diluted so that the salinity is decreased. This may occur in areas of
high rainfall or in coastal regions where rivers flow into the ocean. Thus salinity may be increased by the subtraction of water by-evaporation, or decreased by the addition of fresh water by precipitation.
Normally, in hot regions where the sun is very strong, the ocean salinity is somewhat higher than it is in other parts of the world where there is not as much evaporation. Similarly, in coastal regions where rivers dilute the sea, salinity is somewhat lower than in other oceanic areas.
A third process by which salinity may be altered is associated with the formation and melting of sea ice. When seawater is frozen, the dissolved materials are left behind. In this manner, seawater directly beneath freshly formed sea ice has a higher salinity than it did before the ice appeared. Of course, when this ice melts, it will tend to decrease the salinity of the surrounding water.
In the Weddell Sea, the densest water in the ocean is formed as a result of this freezing process, which increases the salinity of cold water. This heavy water sinks and is found in the deeper portion of the oceans of the world.
Which of the following statements is TRUE according to the passage?
查看材料
A．Oceanic salinity has great effect on sea life.
B．Many factors combine to cause changes in oceanic salinity.
C．The movement of the water is related to the amount of salt.
D．The temperature of the water has much to do with the oceanic salinity.
考题
共用题干
Where Has the Salt Come from?Every now and then,we meet a fact about our earth that makes us feel strange and no answer for the fact has yet been found.Such a fact is the existence of salt in the oceans. How did it get there?We simply do not know how the salt got into the ocean!We do know,of course,that salt is water-soluble,and so passes into the oceans with rainwater.The salt of the earth's surface is constantly being dissolved（溶解）and is passing into the ocean.But we do not know whether this can explain the huge quantity of salt in oceans.If all the oceans were dried up,enough salt would be left to build a wall 180 miles high and a mile thick. Such a wall would reach once around the world at the Equator（赤道）!The common salt that we all use is produced from seawater or the water of salt lakes, from salt springs（源泉）and from deposits of rock salt. The concentration（浓度）of salt in seawater ranges from about three percent to three-and-one-half percent. The Dead Sea, which covers an area of about 340 square miles,contains about 11,600,000,000 tons of salt!On the average, a gallon（加仑）of seawater contains about a quarter of a pound of salt.The beds of rock salt that are found in various parts of the world were all originally formed by the evaporation（蒸发）of seawater millions of years ago. It is believed that the thick rock-salt deposits were formed after about nine-tenth of theY volume of seawater had been evaporated.Most commercial salt is obtained from rock salt.The usual method is to drill wells（井） down to the salt beds. Pure water is pumped down（抽进去）through a pipe. The water dissolves the salt and it is forced through another pipe up to the surface.A:Right B:Wrong C:Not mentioned
考题
共用题干
Where Has the Salt Come from?Every now and then,we meet a fact about our earth that makes us feel strange and no answer for the fact has yet been found.Such a fact is the existence of salt in the oceans. How did it get there?We simply do not know how the salt got into the ocean!We do know,of course,that salt is water-soluble,and so passes into the oceans with rainwater.The salt of the earth's surface is constantly being dissolved（溶解）and is passing into the ocean.But we do not know whether this can explain the huge quantity of salt in oceans.If all the oceans were dried up,enough salt would be left to build a wall 180 miles high and a mile thick. Such a wall would reach once around the world at the Equator（赤道）!The common salt that we all use is produced from seawater or the water of salt lakes, from salt springs（源泉）and from deposits of rock salt. The concentration（浓度）of salt in seawater ranges from about three percent to three-and-one-half percent. The Dead Sea, which covers an area of about 340 square miles,contains about 11,600,000,000 tons of salt!On the average, a gallon（加仑）of seawater contains about a quarter of a pound of salt.The beds of rock salt that are found in various parts of the world were all originally formed by the evaporation（蒸发）of seawater millions of years ago. It is believed that the thick rock-salt deposits were formed after about nine-tenth of theY volume of seawater had been evaporated.Most commercial salt is obtained from rock salt.The usual method is to drill wells（井） down to the salt beds. Pure water is pumped down（抽进去）through a pipe. The water dissolves the salt and it is forced through another pipe up to the surface.Beds of rock salt are found in every part of the world.A:Right B:Wrong C:Not mentioned
考题
共用题干
Where Has the Salt Come from?Every now and then,we meet a fact about our earth that makes us feel strange and no answer for the fact has yet been found.Such a fact is the existence of salt in the oceans. How did it get there?We simply do not know how the salt got into the ocean!We do know,of course,that salt is water-soluble,and so passes into the oceans with rainwater.The salt of the earth's surface is constantly being dissolved（溶解）and is passing into the ocean.But we do not know whether this can explain the huge quantity of salt in oceans.If all the oceans were dried up,enough salt would be left to build a wall 180 miles high and a mile thick. Such a wall would reach once around the world at the Equator（赤道）!The common salt that we all use is produced from seawater or the water of salt lakes, from salt springs（源泉）and from deposits of rock salt. The concentration（浓度）of salt in seawater ranges from about three percent to three-and-one-half percent. The Dead Sea, which covers an area of about 340 square miles,contains about 11,600,000,000 tons of salt!On the average, a gallon（加仑）of seawater contains about a quarter of a pound of salt.The beds of rock salt that are found in various parts of the world were all originally formed by the evaporation（蒸发）of seawater millions of years ago. It is believed that the thick rock-salt deposits were formed after about nine-tenth of theY volume of seawater had been evaporated.Most commercial salt is obtained from rock salt.The usual method is to drill wells（井） down to the salt beds. Pure water is pumped down（抽进去）through a pipe. The water dissolves the salt and it is forced through another pipe up to the surface.The author is sure that the dissolved salt from the earth's surface is the only source of the huge quantity of salt found in oceans.A:Right B:Wrong C:Not mentioned
考题
单选题Drinking salt water will（）.A
be safe if mixed with fresh waterB
prevent seasicknessC
dehydrate youD
protect against heat cramps
考题
单选题The vacuum maintained in the salt water feed heater shell of a flash-type evaporator is generally accomplished by （）.A
a separate air ejector unitB
a direct unimpeded connection between second stage and salt water feed heaterC
either by vacuum drag or an external line from the first stage via a fixed orificeD
the fixed orifice provided in the steam supply line
考题
单选题Passage2 Questions 6 to 10 are based on the following passage. Salt is as necessary to life as water. In many areas of Africa people once drank the urine（尿）of animals because they had no other source of salt. Without salt, human beings die. The human body demands that the amount of salt in the blood always stay the same. When the body does not get enough salt, it protects itself by letting less salt leave the body in. urine and sweat. But it cannot reduce this output to zero. Some salt is always escaping. On a completely saltless diet, like that of some people in Africa, the body steadily loses small amounts of salt through the kidneys（肾） and sweat glands(腺). It then tries to adjust to this loss by speeding up its secretion(分泌) of water. (78) In this way, the body attempts to keep the amount of salt in the blood at the necessary level. The result is a slow drying up of body and, finally, death. The person dies of thirst. In cases where there is little or no water to drink, the body tries to do the opposite thing.Again, it must keep the salt level in the blood constant. Because it has little water, it attempts to stop water from leaving the body and to increase its secretion of. salt. But, as with the escaping salt, it cannot be completely successful. Some water still leaves and the person eventually dies of thirst. In short, the body's normal needs for salt and for water are both parts of the same important need to keep the salt level in the blood constant.6 Some African people once drank animal urine______.A
when they were going to dieB
because they were thirstyC
because there was little saltD
because they were short of water
考题
单选题Passage2 Questions 6 to 10 are based on the following passage. Salt is as necessary to life as water. In many areas of Africa people once drank the urine（尿）of animals because they had no other source of salt. Without salt, human beings die. The human body demands that the amount of salt in the blood always stay the same. When the body does not get enough salt, it protects itself by letting less salt leave the body in. urine and sweat. But it cannot reduce this output to zero. Some salt is always escaping. On a completely saltless diet, like that of some people in Africa, the body steadily loses small amounts of salt through the kidneys（肾） and sweat glands(腺). It then tries to adjust to this loss by speeding up its secretion(分泌) of water. (78) In this way, the body attempts to keep the amount of salt in the blood at the necessary level. The result is a slow drying up of body and, finally, death. The person dies of thirst. In cases where there is little or no water to drink, the body tries to do the opposite thing.Again, it must keep the salt level in the blood constant. Because it has little water, it attempts to stop water from leaving the body and to increase its secretion of. salt. But, as with the escaping salt, it cannot be completely successful. Some water still leaves and the person eventually dies of thirst. In short, the body's normal needs for salt and for water are both parts of the same important need to keep the salt level in the blood constant.10 What is the main idea of the passage?A
Salt is very important.B
If their blood salt level is not constant, human beings may die.C
The amount of salt in the body is secreted.D
People can die of thirst.
考题
单选题What should you apply to a fathometer reading to determine the depth of water?（）A
Subtract the draft of the vesselB
Add the draft of the vesselC
Subtract the sea water correctionD
Add the sea water correction
考题
单选题If a small electric motor is immersed in salt water it should be （） (1) washed in fresh water (2) dried in an ovenA
(1) onlyB
(2) onlyC
both (1) and (2)D
neither (1) or (2)
考题
单选题What does salt water draft mean?（）.A
It means summer draftB
It means maximum draftC
It means fresh water draftD
It means seawater draft
考题
单选题A salinity indicator is used to determine the （）.A
cause of salt contaminationB
location of salt water contaminationC
chemical makeup of feed-waterD
level of alkalinity in condensate
考题
单选题When distilling salt water the cooling water discharging from the distiller is fed back to evaporator as feed water （）.A
to cut down the amount of cooling water neededB
to prevent an excess amount of cooling water from being discharged to the bilgesC
to supply hot water to the evaporator for more economical operationD
None of the above is tree
考题
单选题（） is used for cylinder and cylinder head, the salt water is used for cooling the lubricating oil, the fresh water in the coolers and the charging air in the air cooler.A
The fuel oilB
The lube oilC
The sea waterD
The fresh water
考题
单选题Which（）need NOT be entered in the Official Logbook?A
The testing of the internal combustion engine driven emergency generators at least once each month the vessel is navigatedB
The testing of storage batteries for emergency lighting and power systems once each 6 months the vessel is navigatedC
The actual draft when the vessel arrives in salt water after departing a portD
The testing of the line-throwing appliance once every 3 months
考题
单选题（）of the following need not be entered in the official logbook?A
The testing of the internal combustion engine driven emergency generator at least once each month the vessel is navigatedB
The testing of storage betteries for emergency lighting and systems once each 6 months the vessels is navigatedC
The actual draft when the vessel arrives in salt water after department a portD
The testing of the line-throwing appliance once every 3 months
考题
单选题Passage2 Questions 6 to 10 are based on the following passage. Salt is as necessary to life as water. In many areas of Africa people once drank the urine（尿）of animals because they had no other source of salt. Without salt, human beings die. The human body demands that the amount of salt in the blood always stay the same. When the body does not get enough salt, it protects itself by letting less salt leave the body in. urine and sweat. But it cannot reduce this output to zero. Some salt is always escaping. On a completely saltless diet, like that of some people in Africa, the body steadily loses small amounts of salt through the kidneys（肾） and sweat glands(腺). It then tries to adjust to this loss by speeding up its secretion(分泌) of water. (78) In this way, the body attempts to keep the amount of salt in the blood at the necessary level. The result is a slow drying up of body and, finally, death. The person dies of thirst. In cases where there is little or no water to drink, the body tries to do the opposite thing.Again, it must keep the salt level in the blood constant. Because it has little water, it attempts to stop water from leaving the body and to increase its secretion of. salt. But, as with the escaping salt, it cannot be completely successful. Some water still leaves and the person eventually dies of thirst. In short, the body's normal needs for salt and for water are both parts of the same important need to keep the salt level in the blood constant.7 In order to adjust to the loss of salt, the body______.A
loses some bloodB
speeds up its secretion of waterC
speeds up its secretion of saltD
is drying up slowly
考题
单选题In motorships，there are two main circuits, （）.A
one salt water, one fresh waterB
one salt water, one fuelC
one fresh water, one fuelD
one steam, one fuel
考题
单选题（）provides strength and strong space for fule,lubricating oil,fresh water,salt(ballast)water and potable water.A
The double bottomB
The cofferdamC
The navigating bridgeD
The superstructure
考题
单选题Passage2 Questions 6 to 10 are based on the following passage. Salt is as necessary to life as water. In many areas of Africa people once drank the urine（尿）of animals because they had no other source of salt. Without salt, human beings die. The human body demands that the amount of salt in the blood always stay the same. When the body does not get enough salt, it protects itself by letting less salt leave the body in. urine and sweat. But it cannot reduce this output to zero. Some salt is always escaping. On a completely saltless diet, like that of some people in Africa, the body steadily loses small amounts of salt through the kidneys（肾） and sweat glands(腺). It then tries to adjust to this loss by speeding up its secretion(分泌) of water. (78) In this way, the body attempts to keep the amount of salt in the blood at the necessary level. The result is a slow drying up of body and, finally, death. The person dies of thirst. In cases where there is little or no water to drink, the body tries to do the opposite thing.Again, it must keep the salt level in the blood constant. Because it has little water, it attempts to stop water from leaving the body and to increase its secretion of. salt. But, as with the escaping salt, it cannot be completely successful. Some water still leaves and the person eventually dies of thirst. In short, the body's normal needs for salt and for water are both parts of the same important need to keep the salt level in the blood constant.8 Which of the following statements is NOT the result of a lack of salt in the body?A
The body secretes more water.B
The body dries up.C
The person dies of thirst.D
The person gets fatter.
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