相关试题
共用题干
Improve Your Memory
To many people advancing age means losing your hair,your waistline and your memory.But is it an inescapable fact that the older you get,the less you remember? Well,as time goes by,we tend to blame age for problems that are not necessarily age-related.
When a teenager can't find her keys,she thinks it's because she's distracted or disorganized, but a 70-year-old blames her memory. In fact,the 70-year-old may have been misplacing things for decades一like we all do from time to time.
In healthy people,memory doesn't deteriorate as quickly as many of us think. According to psychologists,as we age,our memory mechanism isn't broken,it's just different.The brain's processing time slows down over the years,though no one knows exactly why.Recent research suggests that nerve cells lose efficiency and that there's less activity in the part of the brain that decides whether to store information or not.But it's not clear that less activity is worse.A beginning athlete is winded. more easily than a trained athlete.In the same way,as the brain gets more skilled at a task,it spends less energy on it.
There are steps you can take to improve your memory,though you have to work to keep your brain in shape.It's like having a good body. You can't go to the gym once a year and expect to stay in top form.
Some memory enhancement experts suggest using the AM principle.Pay attention to what you want to remember. Then give some meaning to it. We remember things when we focus on them, whether we intend to or not. That helps explain why jingles stick in our minds.They are played on loud,flashy TV commercials.They also use rhyme and music to help us remember better.
Basic organization helps us remember the boring stuff. For example,rather than trying to recall a random list of groceries,we can divide them into categories,such as dairy,meat and produce. For important things like keys and money,we can set up a"forget-me-not"spot where we always keep them.
We can also eat to aid our memory power. Whole grains,fruits and vegetables are excellent sources of glucose,the brain's preferred fuel. Another low-tech way to improve memory is to get adequate rest. Sleep may allow our brain time to encode memories.
Interest in friends,family and hobbies does wonders for our memory.A sense of passion or purpose helps us remember. Memory requires us to pay attention to our lives,allowing us to discover in them everything worth remembering.
In the AM principle,the letters A and M most likely refer to attention and memory respectively.
A:Right
B:Wrong
C:Not mentioned
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Transport and Trade
1.Transport is one of the aids to trade.By moving goods from places where they are plentiful to places where they are scarce,transport adds to their value.The more easily goods can be brought over the distance that separates producer and consumer,the better for trade.When there were no railways,no good roads,no canals,and only small sailing ships,trade was on a small scale.
2.The great advances made in transport during the last two hundred years were accompanied by a big increase in trade.Bigger and faster ships enabled a trade in meat to develop between Britain and New Zealand,for instance.Quicker transport makes possible mass-production and big business, drawing supplies from,and selling goods to,all parts of the globe.Big factories could not exist with-out transport to carry the large number of workers they need to and from their homes.Big city stores could not have developed unless customers could travel easily from the suburbs and goods delivered to their homes.Big cities could not survive unless food could be brought from a distance.
3.Transport also prevents waste.Much of the fish landed at the ports would be wasted if it could not be taken quickly to inland towns.Transport has given us a much greater variety of foods and goods since we no longer have to live on what is produced locally.Foods which at one time could be obtained only during a part of the year can now, be obtained all through the year. Transport has raised the standard of living.
4.By moving fuel,raw materials,and even power,as,for example,through electric cables, transport has led to the establishment of industries and trade in areas where they would have been impossible before.Districts and countries can concentrate on making things which they can do better and more cheaply than others and can then exchange them with one another. The cheaper and quicker transport becomes,the longer the distance over which goods can profitably be carried.Countries with poor transport have a lower standard of living.
5.Commerce requires not only the moving of goods and people but also the carrying of messages and information. Means of communication,like telephones,cables and radio,send information about prices,supplies,and changing conditions in different parts of the world.In this way,advanced communication systems also help to develop trade.
In the trade of modern society the transmission of information plays as important a role as_______.
A:to send goods to various parts of the world
B:at any time during the year
C:has greatly promoted trade
D:is it possible to produce on a large scale
E:the transport of goods
F: it is possible to produce on a large scale
共用题干
第一篇
Can Buildings Be Designed to Resist Terrorist Attack?
In the aftermath of the terrorist attack on the World Trade Center,structural engineers are trying hard to
solve a question that a month ago would have been completely unthinkable:Can buildings be designed to
withstand catastrophic blasts inflicted by terrorists?
Ten days after the terrorist attacks on the twin towers,structural engineers from the University at Buffalo
and the Multidisciplinary Center for Earthquake Engineering Research(MCEER)headquartered at UB
traveled to ground zero as part of a project funded by the National Science Foundation.Visiting the site as
part of an MCEER reconnaissance visit,they spent two days beginning the task of formulating ideas about
how to design such structures arid to search for clues on how to do so in buildings that were damaged but still
are standing.
"Our objective in visiting ground zero was to go and look at the buildings surrounding the World Trade
Center,those buildings that are still standing,but that sustained damage,"said M.Bruneau,Ph.D."Our im-
mediate hope is that we can develop a better understanding as to why those buildings remain standing,while
our long-term goal is to see whether earthquake engineering technologies can be married to existing technolo-
gies to achieve enhanced performance of buildings in the event of terrorist attacks,"he added.
Photographs taken by the investigators demonstrate in startling detail the monumental damage inflicteed
on the World Trade Center towers and buildings in the vicinity.One building a block away from the towers
remains standing,but was badly damaged."This building is many meters away from the World Trade Center
and yet we see a column there that used to be part of that building,"explained A.Whittaker,Ph.D."The
column became a missile that shot across the road,through the window arid through the floor."
The visit to the area also revealed some surprises,according to the engineers.For example,the floor
framing system in one of the adjacent buildings was quite rugged,allowing floors that were pierced by tons of
falling debris to remain intact. " Highly redundant ductile（有延展性的）framing systems may provide a sim-
pie,but robust strategy for blast resistance,"he added.Other strategies may include providing alternate paths
for gravity loads in the event that a load一bearing column fails."We also need a better understanding of the
mechanism of collapse,"said A.Whittaker."We need to find out what causes a building to collapse and how
you can predict it."
A.Reinhorn,Ph.D.noted that"Earthquake shaking has led to the collapse of many buildings in the
past.It induces dynamic response and extremely high stresses and deformations in structural components.So-
lutions developed for earthquake-resistant design may be directly applicable to blast engineering and
terrorist-resistant design.Part of our mission now at UB is to transfer these solutions and to develop new ones
where none exist at present."
The question raised in the first paragraph is one_______.
A:that was asked by structural engineers a month ago
B:that is too difficult for structural engineers to answer even now
C:that was never imagined before the terrorist attack
D:that terrorists are eager to find a solution to
共用题干
Obtaining Drinking Water from Air Humidity
Not a plant to be seen,the desert ground is too dry.But the air contains water,and research scientists
have found a. __________
(51)of obtaining drinking water from air humidity."The process we have
developed is based exclusively on renewable energy sources_________(52)thermal solar collectors and
photovoltaic（光电的）cells , ________( 53 ) makes this method completely energy-autonomous. It will
____________( 54 ) function in regions where there is no electrical infrastructure（基础设施）,"says Siegfried
Egner,head of the research team. The principle of the_________(55)is as follows:hygroscopic（吸湿的）
brine（盐水）一saline（含盐的）solution which absorbs moisture一runs down a tower-shaped unit and absorbs
water from the air. It is then sucked__________(56)a tank a few meters off the ground in which a vacuum
prevails.Energy from solar collectors_________(57)up the brine,which is diluted by the water it has
__________ (58).
Because of the vacuum,the boiling point of the liquid is lower than it would be under__________(59)
atmospheric pressure. The evaporated (蒸发的）, non-saline water is condensed and runs down through a
completely filled tube in a controlled manner. The gravity of this water column_______(60)produces the
vacuum and so a vacuum pump is not needed.The reconcentrated brine________(61)down the tower
surface again to absorb moisture from the air.
"The concept is suitable for various water________(62).Single一person units and plants
supplying water to entire hotels are conceivable,"says Egner. Prototypes have been built for_______
(63)system components一air moisture absorption and vacuum evaporation一and the research scientists
have already __________(64)their interplay on a laboratory scale.In a further ________(65)the re-
searchers intend to develop a demonstration facility.
_________(65)
A:instrument
B:step
C:case
D:ground
共用题干
Singing Alarms Could Save the Blind.
If you cannot see,you may not be able to find your way out of a burning building-and that could be fatal .A company in Leeds could change all that______(51)directional sound alarms capable of guiding you to the exit.
Sound Alert,a company______(52)the University of Leeds,is installing the alarms in a residential home for______(53)people in Sommerset and a resource centre for the blind in
Cumbria.______(54)produce a wide range of frequencies that enable the brain to determine where the______（55)is coming from.
Deborah Withington of Sound Alert says that the alarms use most of the frequencies that can be______（56)by humans."It is a burst of white noise ______(57)people say sounds like static on the radio,"she says."Its life-saving potential is great."
She conducted an experiment in which people were filmed by thermal-imaging cameras trying to find their way out of a large______(58)room. It______(59)them nearly four minutes to find the door______(60)a sound alarm,but only 15 seconds with one.
Withington studies how the brain______(61)sounds at the university. She says that the _______(62)of a wide band of frequencies can be pinpointed more easily than the source of a narrow band .Alarms______(63)the same concept have already been installed on emergency vehicles.
The alarms will also include rising or falling frequencies to indicate whether people should go up______(64)down stairs.They were______（65)with the aid of a large grant from British Nuclear Fuels.
58._________
A: smoked
B: smoke-filled
C: filled with smoke
D: smoke-filling
