题目内容
根据短文回答 23～30 题。
Can Mobile Phones Cause Disease？
1 "Mobile phone killed my man," screamed one headline last year.Also came claims that an unpublished study had found that mobile phones cause memory loss.And a British newspaper devoted its front page to a picture supposedly(假定地)showing how mobile phones heat the brain.
2 For anyone who uses a mobile phone,these are worrying times.But speak to the scientists whose work is the focus of these scares and you will hear a different story. According to them,there is no evidence that mobile phones cause cancer or any other illness in people.
3 What we do have,however, are some results suggesting that mobile phones' emissions have a variety of strange effects on living tissue that can't be explained by the general radiation biology.And it's only when the questions raised by these experiments are answered that we' be able to say for Sure what mobile phones might be doing to the head.
4 One of the odd effects comes from the now famous" memory loss" study.Alan Preece and his colleagues at the University of Bristol placed a device that imitated the microwave emissions of mobile phones to the Left ear of volunteers.The volunteers were just as good at recalling words and pictures they had been shown on a computer screen, whether or not the device was switched on.Preece says he still can't comment or the effects of using a mobile phone for years on end.But he rules out the suggestion that mobile phones have an immediate effect on our cognitive abilities,"I'm pretty sure there is no effect on short-term memory," he says.
5 Another expert,Tatters all,remarked that his latest findings have removed fears about memory loss.One result,for instance,suggests that nerve cell synapses(突触) exposed to microwaves become more-rather than less-receptive(感受的)to undergoing changes linked to memory formation.
6 Hopefully, microwaves might turn out to be good for you.It sounds crazy, but 3 couple of years ago a team led by William Adey at the Veterans Affairs Medical Center in California found that mice exposed to microwaves for two hours a day were Less Likely to develop brain tumours when given a cancer-causing chemical.
第 23 题 paragraph 2_____________
查看答案
搜索结果不匹配？点我反馈
更多问题
Andersen's fairy tales didn't achieve success until after he died.（）
It is absurd to predict that the sun will not rise tomowow.（）
请选择（6）处的最佳答案。
根据下面材料请回答 51～65 题
Less Is More
It sounds all wrong--drilling holes in a piece of wood to make it more resistant to knocks.But it works because the energy from the blow gets distributed throughout the wood rather than focusing on one weak spot.The discovery should lead to more effective and lighter packaging materials.
Carpenters have known________ (1)centuries that some woods are tougher than others.Hickory(山核桃木),for example,was turned into axe handles and cartwheel spokes(轮辐)because it can absorb shocks without breakin9.White oak,for example,is much more easily damaged,________ (2)it is almost as dense.Julian Vincent at Bathe University and his team were convinced the wood'S internal structure could explain the differences.
Many trees have tubular(管的)vessels that run________ (3)the trunk and carry water to the leaves.In oak they are large,and arranged in narrow bands,but.Il hickory they are smaller, and more evenly distributed.The researchers________ (4)this layout might distribute a blow's energy throughout the wood,soaking up a bigger hit.To test time idea,they drilled holes 0.65 millimeters across into a block of spruce(云杉),a wood with________ (5)vessels,and found that________ (6)withstood a harder knock.________ (7) when there were more than about 30 holes per square centimeter did the wood。S performance drop off.
A uniform. substance doesn‘t cope well with knocks because only a small proportion of the material is actually________ (8).All the energy from the blow goes towards breaking the material in one or two places,but often the pieces left________ (9)are pristine(未经破坏的).
But instead of the energy being concentrated in one place,the holes provide many weak spots that all absorb energy as they break,says Vincent."You are controlling the places________ (10)the wood breaks,and it can then absorb more________ (11),more safely."
The researchers believe the principle could be applied to any material________ (12)example,to manufacture lighter and more protective packaging.It could ________ (13)be used in car bumpers,crash barriers and armour for military vehicles,
says Ulrike Wegst________ (14) the Max Plank Institute for Mental Research in Stuttgart.But she emphasizes that you________ (15)to design the substance with the direction of force in mind."The direction of loading is crucial,"she says.
第 51 题
微信支付 
支付宝支付