-
电气设备（electrical equipment）
-
电气分隔（electrical separation）
-
If a person is unconscious from electric shock，you should first remove him from the electrical source and then（）.
A . administer ammonia smelling salts
B . check for serious burns on the body
C . determine if he is breathing
D . massage vigorously to restore circulatio
-
（） is a machine by which electrical energy is transformed into mechanical energy.
A . An alternator
B . An electric motor
C . A diesel engine
D . A main switchboard
-
电烧伤electric burn
-
（）on board ship are used to control and distribute the electrical energy generated by generators.
A . A.Governors
B . B.Alternators
C . C.Blackboards
D . D.Switchboards
-
Which of the following centrifugal pump components converts the liquid kinetic energy of velocity to the potential energy of pressure?（）
A . Impeller
B . Electric motor
C . Volute
D . Eye
-
电击（electric shock）
-
英语ELECTRICAL指（）
A . A、电动的
B . B、气动的
C . C、电磁阀
D . D、转换器
-
Electrical conductivity（）
A . 电导率
B . 载流子数
C . 载流子迁移率
-
（） is used to produce electric power.
A、The generator and bus transfer section.
B、The 450 volt, 60 cycle, 3 phase bus.
C、The 120 volt, 3 phase, 60-cycle bus.
D、The 24 volt DC bus.
-
When a rescuer finds an electrical burn victim in the vicinity of live electrical equipment or wiring，his first step is to（）.
A . flush water over any burned area of the patient
B . apply ointment to the burned areas on the patient
C . get assistance to shut down electrical power in the area
D . remove the patient from the vicinity of the live electrical equipment or wiring
-
Electrical power is expressed in （）
A . ohms
B . volts
C . amps
D . watt
-
Machinery operating features are designed to help conserve energy.Which of the following results will not contribute to energy conservation?（）
A . Reduction of friction
B . Insulation of hot surfaces
C . Lubrication of moving parts
D . Elevation of cooler outlet temperature
-
The solar cell can _____ the energy of sunlight into electric energy.
-
Various energy-saving facilities are installed in Janet’s house to reduce the energy bills.
-
The device capable of doing this is called a capacitor. The ability of a capacitor to store electrical energy is termed capacitance.（）
-
According to the opponents of nuclear energy, which of the following is true of nuclear energy？
A) Primitive
B) Exhaustible
C) Cheap
D) Unsafe
-
In a diesel engine, offers the heat energy directly; works as working medium and changes the heat energy to mechanical energy.
A.the burning of the fuel; medium shaft
B.fuel spray; fresh air
C.fuel; fuel spray
D.the burning of the fuel; the burned gas mixture
-
听力原文： Most industrialized nations have gone through two major energy transitions. By energy transition we mean a change from one major source of energy to another.
The first major energy transition was from wood to coal. For many centuries people used wood as a primary source of energy. By burning wood people were able to heat their homes, cook their food, and produce basic items. Most early societies grew up near a sufficient supply of wood. The main advantage of wood was that it was easy to get and easy to bum.
During the early 1800's, some towns and villages began to make a transition from wood to coal as a basic source of energy, because they found that coal generally burns longer and at a higher temperature than wood, and a long-burning and hot-burning fuel was badly needed for the machines that were being used at that time. Another advantage of coal was that there was a lot of it and it was also easy to get. Besides, it could be easily shipped to faraway places.
As a result of the transition from wood to coal, industry developed very rapidly. People were able to get more things and their standard of living went up.
The second major energy transition was from coal to oil. We'll discuss it next week.
Why did most early societies grow up near a sufficient supply of wood？
A．Because wood was safer than coal.
B．Because wood burned longer than coal.
C．Because there was more wood than coal.
D．Because they used wood as primary source energy.
-
Where do cars get their energy from？ For most cars, the answer is petrol. 1_____some cars use electricity. These cars have 2 _____motors that get their power from large batteries. In 3___, there are even cars that have 4_____ an electric motor and a petrol motor. These types of cars are 5_____ hybrid (混合) cars.
Most people tend to think of electric cars as a new 6 ____, but they have been around for a long time. In the 7_____ 19th and early 20th centuries electric cars were common because the technology for petrol engines was not very advanced.But 8____ the petrol engine became easier to make and more powerful, this type of engines became the most 9 ____.Interest in electric cars was high in the l970s and 1980s because 10____ became very expensive.Recently, electric cars have again become well-liked because people want cars that pollute 11_____.
Electric cars are better than petrol cars 12______ several ways. The biggest benefit is reduced pollution.In areas 13_____ there is a high percentage of electric cars, pollution is not that serious. The second benefit of electric cars is a 14 _____in the dependence on foreign oil.Several countries don’t want to 15 _____on oil from other countries. Since electric cars can run on electricity from coal or nuclear power stations, there is less need to import oil.
(15分)
(1)第1题最佳答案应选()(1分)
A. But
B. Nor
C. Or
D. And
(2)第2题最佳答案应选()(1分)
A. traditional
B. common
C. same
D. special
(3)第3题最佳答案应选()(1分)
A. summary
B. detail
C. time
D. addition
(4)第4题最佳答案应选()(1分)
A. all
B. both
C. either
D. neither
(5)第5题最佳答案应选()(1分)
A. described
B. regarded
C. called
D. known
(6)第6题最佳答案应选()(1分)
A. invention
B. influence
C. instrument
D. intention
(7)第7题最佳答案应选()(1分)
A. last
B. beginning
C. recent
D. late
(8)第8题最佳答案应选()(1分)
A. unless
B. after
C. before
D. until
(9)第9题最佳答案应选()(1分)
A. popular
B. comfortable
C. difficult
D. dangerous
(10)第10题最佳答案应选()(1分)
A. motors
B. power
C. cars
D. oil
(11)第11题最佳答案应选()(1分)
A. much
B. more
C. less
D. few
(12)第12题最佳答案应选()(1分)
A. by
B. in
C. at
D. on
(13)第13题最佳答案应选()(1分)
A. when
B. where
C. what
D. which
(14)第14题最佳答案应选()(1分)
A. start
B. need
C. reduction
D. rise
(15)第15题最佳答案应选()(1分)
A. put
B. hold
C. rely
D. keep
-
Solar-generated electricity docs not carry the health or environmental risks of nuclear energy. We can never run out of solar energy, because the sun is a renewable energy source.
Two kinds of systems generate solar energy: passive and active. A passive solar energy system generates energy from fixed glass plates built into the structure, without the use of mechanical devices. A greenhouse is a good example of a building heated by passive solar energy. The sun's rays penetrate the glass panels to heat the interior of the greenhouse, and the heat is retained through tight construction. The same principle can be applied to heating homes and other buildings on sunny days.
An active solar energy system makes use of mechanical devices and moving parts to maximize the amount of energy collected. For example, solar energy can be generated with photovoltaic cells, which are made from silicon, an abundant element. A bank of photovoltaic cells can be encased in glass and wired together to produce electricity. The bank of cells can be mounted on the roof at an angle that maximizes exposure to direct sunlight.
Another device to generate solar energy is a flatplate collector, which is an insulated glass box, typically placed on the sun-facing roof. Inside the box are pipes filled with air or water. The heat that builds up in the pipes can be used for home heating and hot-water supplies.
Two questions persist about solar energy:
How can solar energy be used in colder climates？
How can solar energy be used on cloudy days？
Scientists have the technological means to overcome both problems, but the solutions may make solar energy more expensive for many people than other alternatives.
The energy released from the sun is about 10,000 degrees F, but by the time the rays reach the earth the temperature is considerably lower, because the sun's energy has diffused over a large area during its long journey. To be useful energy in colder climates, the sun's diffused rays must be concentrated.
The process of concentrating the sun's rays is not difficult. Scouts learn that sunlight focused with a lens at the proper angle can burn a piece of paper. In warmer climates, the sun's rays can provide heat and hot water with little concentration. In colder climates, compensation is made simply by collecting more of the sun's rays by building a larger collecting device and rotating the lenses as the sun's position in the sky changes. In cloudy weather, another system can store the energy generated from the sun. For example, water heated by the sun can be retained in protected storage containers.
Because of high installation coasts, solar energy is more expensive than other sources of energy for most consumers. At this time, electricity provided by a solar power plant costs two or three times the amount of a coal-fired plant. But solar equipment is generally installed on the consumer's roof rather than at a central power plant, as is the case with other energy sources. A family must pay several thousand dollars to construct a solar energy system capable of providing virtually all household heat and electricity. The family is also responsible for maintenance and repair of the system.
While initial construction costs are much higher, monthly heating and electricity bills are much lower once the system begins operation. Users of solar energy do not face rising monthly electricity bills from a power company, which passes to its consumers the increasing costs of purchasing fossil fuels and constructing new facilities. Solar energy is economical for consumers who remain in the same house for many years and can benefit from low monthly operating costs. For most families, solar energy will become more attractive when other energy sources become more expensive. One indication of solar energy's bright future is that petroleum companies have bought the m
A．The technical problem of providing heat on cloudy days are not yet solved.
B．It costs much to have a solar energy system installed at home.
C．There are basically two types of solar energy.
D．Solar energy is clean, inexhaustible and free of risk.
-
Renewable energy sources can be replenished in a short period of time. The five renewable sources used most often include hydropower (water), solar, wind, geothermal, and biomass. Renewable energy's impact on the world's energy picture is significant. Many important events have occurred during the history of using renewable sources to generate electricity--but the overall consumption from renewable energy sources has declined by about 15 percent from their I996 peak to about 6 quads in 2005.
The use of renewable energy is not new. Five generations (125 years) ago, wood supplied up to 90 percent of our energy needs. Due to the convenience and low prices of fossil fuels, wood use has fallen. Now, the biomass which would normally present a disposal problem is converted into electricity (e.g., manufacturing wastes, rice hulls, and black liquor from paper production).
Historically, low fossil fuel prices, especially for natural gas, have made growth difficult for renewable fuels. The deregulation and restructuring of the electric power industry could have a major impact on renewable energy consumption. Demands for cheaper power in the short term would likely decrease demand for renewable energy, while preferences for renewables included in some versions of proposed electricity restructuring legislation would breathe new life into this industry.
Use of renewables in the United States is not currently expected to approach that of the major fuels, and due to their limitatious (e.g., their intermittent nature-cloudy days have no solar gain, quiet days mean no wind blows to drive wind turbines, dams are primarily for flood control, so hydroelectricity production varies as dams' water levels change), renewables may never provide "the" answer to all energy problems. Around the world, renewable energy is proving to be of great value.
In 2005, about 6.1 Quadrillion Btu (Quads) of U.S. energy came from renewable fuels. Each of the energy sources we use is measured, purchased, and sold in a different form. Many units of measurement are used to measure the energy we use each day.
From 1996 to 2005, the trend of the consumption from renewable energy was ______.
A．increasing
B．decreasing
C．irregular
D．not mentioned
-
电除颤electric defibrillation 名词解释
