题目内容
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Sulfur has occasionally been found in the earth in an almost pure state.
A．regularly
B．accidentally
C．sometimes
D．successfully
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Sulfur has occasionally been found in the earth in an almost pure state.
A．regularly
B．accidentally
C．sometimes
D．successfully
l shall not exceed globally from January 1, 2020.
A. 0、10% m/m
B. 0、50% v
C. 0、50% m/m
D. 0、10% v
A．There is no greenhouse gas now, since it has been well under control.
B．Now the production of CFCs used in refrigerators is only one third of that in the mid- 1980s.
C．Oxides of sulfur can lead to acid rain and smog.
D．The amount of lead, soot and carbon monoxide that are sent out has been reduced sharply.
A．The former is cheaper and has higher sulfur content than the latter.
B．The latter is found closer to the surface and contains more sulfur than the former.
C．The former can help coal-burning power plants meet limits on sulfur dioxide emissions and costs more than the latter.
D．The latter generates more energy per pound of coal than the former.
E．The former is found closer to the surface than the latter and helps coal-burning power plants meet limits on sulfur dioxide emissions.
According to Paragraph 4, what can be inferred about "sweet" natural gas？
A．It is more valuable than pure methane gas.
B．It contains more sulfur than "sour" natural gas.
C．It has high concentrations of propane and butane.
D．It requires less refining than "sour" natural gas.
What brought about the downpour was a study commissioned by Presidential Science Adviser. The spokesmen plainly called for remedial action even if some technical questions about acid rain were still unanswered. "If we take the conservative point of view that we must wait until the scientific knowledge is definitive," said the spokesman, "The accumulated deposition and damaged environment may reach the point of 'irreversibility.'"
When it rains, it pours. Next came a study from the National Research Council. Its definitive conclusion: reducing emissions of sulfur dioxide from coal-burning power plants and factories, such as these in the Midwest, would in fact significantly reduce the acidity in rain, snow and other precipitation that is widely believed to be worsening the life from fresh-water lakes and forests in the Northeast and Canada. The spokesman did not recommend any specific action.
A pair of remedial measures are already taken before Congress. A Senate committee recently approved a bill that would require reduction over the next decade of sulfur-dioxide emissions by 10 million tons in the States bordering on the east of the Mississippi. A tougher measure was introduced in the House ordering the 50 largest sulfur polluters in the U.S. to cut emissions substantially. To ease the Eastern coal mining industry, which fears a switch to low-sulfur Western coal, the bill requires the installation of expensive "scrubbers", devices for removing sulfur from the smoke, rather than an order that forbids high-sulfur fuel. Still, the legislation is being vigorously opposed by the coal industry and utilities, especially in the Mid-west, where heavy industries are battling to survive. In a survey also released last week, the Edison Electric Institute, an industry group, gravely predicted that electricity rates could rise as much as 50% if the emission-control legislation passed.
Government studies dispute these figures, but Congress has been suspended on acid-rain measures. Now, as a result of the academy study, supporters of the bills are more optimistic. Nevertheless, a major political battle is shaping up.
The first paragraph shows that
A．the Administration has ignored the public anxiety about acid rain.
B．the industrial sulfur emissions need further scientific verification.
C．the spokesmen have denied the presence of proofs of acid rain.
D．scientific evidence has made the cause of acid rain undebatable.
Our earth has been threatened by all kinds of pollutions.
Acid rain is a kind of air pollution which is hanging
over our heads and coming down from many different 【S1】______
ways such as rain and snow. It damages forests, lake and 【S2】______
rivers, buildings and even human health. Several
chemicals, including of sulfur dioxide, nitrogen 【S3】______
oxides and ozone, are involved in causing acid rain.
These chemicals either come directly from power
station chimneys and cars, and are formed from a 【S4】______
combination of pollutant gases. Sulfur dioxide is the
one chemical what is often associated with acid rain. 【S5】______
It is mainly emitted by large coal burning power
stations. It affect places thousands of miles away as 【S6】______
well as areas around the power stations. To prevent
more or worse environmental effects from acid rain, 【S7】______
we have short-term and long-term solutions. We should 【S8】______
just clean up our power station chimneys and car exhausts.
We should also change the way society thinks and reacts.
We need to conserve energy by decreasing efficiency. 【S9】______
We also need to change our way of transport, that is,
create a more efficient transport system which
depends less on private cars and more a good public 【S10】______
transport network. Everybody should work together
to save the world.
【S1】
The Killer Smog
Cases of Killer Smogs
On the night of December 1st, 1930, a dense fog moved over the Meuse Valley, in Belgium. Many factories in the valley poured smoke and fumes into the foggy air. This created dark smog of smoke and fog combined. People in the valley began to cough and strain for breath. The smog remained for four days. During that time, thousands of people became ill. The hospitals were filled with patients. Sixty people died. Most of them were older persons with heart and lung problems. Finally, a heavy rain washed away the smog. Scientists studied the causes of the disaster. They concluded that the illnesses and deaths were caused by chemicals in the smog.
The first reported event of this kind in the United States happened in Donora, a factory town in a valley near Pittsburgh. In 1948, a killer smog made half of the population sick; there were 17 deaths. Again, older people with lung or heart diseases were hit hardest.
London, England, has always been known for its "black fogs". In the winter of 1952, a milky white fog rolled into the city. It soon turned into black smog as the smoke of the city poured into the air. It was so hard to see that people had to walk in front of the buses to guide them. In this way, the most serious air pollution disaster in history began. When it was over, more than 4,000 people had been killed by the thick black smog.
New York City has had several types of smogs since 1950. Each time, there were from 100 to 400 deaths caused by the smog. Although these smogs were not as deadly as London's, New York City has the worst air pollution problem in the United States.
Causes of Killer Smogs
In all the killer smogs, factories and homes poured smoke and fumes into the air from the furnaces. The chemical fumes combined with the water droplets in the fog to form. harmful substances. These substances caused the illness of those who breathed the polluted air.
Usually, such harmful fumes rise into the upper air and are blown away by the wind. But sometimes there is an unusual weather condition called a temperature inversion. A layer of cold air remains near the ground as smoke and fumes pour into it. This is covered by an upper layer of warm air that acts like a lid. It prevents the polluted cooler air from rising. The harmful fumes pile up and make people ill. These fumes contain sulfur dioxide, soot particles, and other chemicals. The smog may be so thick that airports are closed and chains of collisions occur on the highways.
Another type of smog occurs in Los Angeles. Here the weather may be clear and sunny. But stinging eyes and dry coughs show that harmful chemicals fill the air. The smog is due to invisible gases, mostly from automobile exhausts. Because these chemicals are changed by the sun high up in the air, Los Angeles smog is called photochemical smog. It contains automobile exhaust fumes and nitrogen oxides changed by the sun's rays. Added to these are sulfur dioxide and other fumes from factories and oil refineries. Photochemical smog is found in many large cities all over the world.
Harmful Substances Found in Smogs
Killer smogs don't happen very often, fortunately. But in many large cities, a combination of automobile exhaust fumes, home furnace smoke, and factory waste gases pours into the air. This may also happen in the suburbs, or out in the country, where large factories have been built. A number of harmful substances have been found in the air there. When these substances are breathed in day after day, the health of the population is affected.
Sulfur dioxide is formed when fuels containing sulfur are burned. The sulfur combines with the oxygen in the air to form. sulfur dioxide. This gas probably caused most of the deaths in the killer smogs. It combines with the water droplets in the air, o
A．Y
B．N
C．NG
A.water vapor is an air pollutant in localized areas
B.the definition of air pollution will continue to change
C.a substance becomes an air pollutant only in cities
D.most air pollutants today can be seen or smelled
Air quality in Britain has improved considerably
in the last 30 years. Total emissions of
smoke in the air have risen by over 85 per cent 【1】______
since 1950. The domestic smoking control 【2】______
program has been particularly important in achieving
this result. London and other major cities are no 【3】______
longer have the dense smoke-laden "smogs" of the
1950s, but in central London winter sunshine has 【4】______
increased about 70 per cent since 1958. 【5】______
Since 1990, daily air pollution data from the
British monitoring network has been made available 【6】______
to the public by the Department of the
Environment's Air Quality Bulletins. These give the
concentrations of three main pollutants--ozone, nitrogen
dioxide and sulfur dioxide -- and grade air quality
on a scale between "very weak" and "very 【7】______
good". The information features in television and
radio weather reports, appears in many national and 【8】______
local newspapers. Therefore, the data are available 【9】______
on a special free telephone number and on videotext
systems.
A comprehensive review of the issue of urban
air quality was published in January 1992. Three
independent committees of which experts have been 【10】______
established to advise on different aspects of the problem,
and will set guidelines and targets for air quality.
The network is also being extended and up-
graded at a cost of ￡ 10 million.
【M1】
听力原文：F: We are honoured that you have come to see us, Mr. Mitchell.
M: Thank you, Madam Ii. We're pleased to be here and appreciate your willingness to arrange this meeting on such a short notice.
F: You have indicated that you would like to explore the possibility of an agency relationship with Sinochem with the intent of developing a market for some of our products in your country and perhaps in Canada as well.
M: Yea, that is certainly our current thinking.
F: Perhaps before we begin any detailed discussions, I should give you some idea of the scope of activities of Sinochem.
M: The name "Sinochem' is well known to us, but we would like a little more information about your company. I should tell you that your branch in the U. S. has already informed us that Expert Division No. 4 is responsible for dyestuffs and pigments.
F: Sinochem was established in 1950 and since that time has grown to become one of the largest companies in China, specializing in imports and exports of chemical products. As a result, it has gained a great deal of experience (in foreign trade) and has many foreign clients. The primary products we handle are crude oil and oil products, plastic, rubber, fertilizer and pesticides, ss well as dyestuffs and pigments. You expressed a particular interest in our various dyestuffs as well as our pigments.
M: I glanced through these catalogues and noted the wide variety of products Sinochem offers.
F: You mentioned earlier that you would like to concentrate on dyes for cotton, silk, and linen materials.
M: Yes, that is what we intend to do.
F: In that case, you may wish to take a look at our sulfur and reactive dyes. Sulfur dyes have been around for a very long time and have been used for dying sturdy work clothing from early history. You will note that the variety of eolours in which this sulfur dye is available is somewhat limited, particularly in the bright hues. They are also cheaper than the reactive dyes.
M: I gather then that the reactive dyes are used primarily for fine cottons, silk, and linen.
F: That is correct.
M: I particularly lire the wide variety of bright eolours available in reactive dyes. Is there any difference in price from one colour to another？
F: Yes, there certainly is. The most expensive is the colour, identified as Brilliant Blue KNR, under Sinochem Code No.9607. A cheaper colour dye would ha, for example, Brilliant Red K-JBP; the most economical of course is Black.
M: I assume of course that not much expertise is needed in producing black.
？You will hear part of a business negotiation between Mr. Mitchell and Madam Li.
？For each question 23—30, mark one letter A, B or C for the correct answer.
？You will hear the recording twice.
21. What is the purpose of Mr. Mitchell's visit？
A．To explore the feasibility of setting up agency relationship.
B．To open an agency.
C．To develop his products.
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