首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
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
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
admin
2016-07-17
30
问题
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【C1】______centuries that some woods are tougher than others. Hickory, for example, was turned into axe handles and cartwheel spokes because it can absorb shocks without breaking. White oak, for example, is much more easily damaged, 【C2】______ 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 vessels that run【C3】______the trunk and carry water to the leaves. In oak they are large, and arranged in narrow bands, but in hickory they are smaller, and more evenly distributed. The researchers【C4】______this layout might distribute a blow’s energy throughout the wood, soaking up a bigger hit. To test the idea, they drilled holes 0. 65 millimetres across into a block of spruce, a wood with 【C5】______vessels, and found that 【C6】______withstood a harder knock.【C7】______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【C8】______. All the energy from the blow goes towards breaking the material in one or two places, but often the pieces left【C9】______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【C10】______ the wood breaks, and it can then absorb more【C11】______, more safely. "
The researchers believe the principle could be applied to any material—【C12】______example , to manufacture lighter and more protective packaging. It could【C13】______be used in car bumpers, crash barriers and armor for military vehicles, says Ulrike Wegst, 【C14】______ the Max Plank Institute for Mental Research in Stuttgart. But she emphasizes that you’d 【C15】______to design the substance with the direction of force in mind. "The direction of loading is crucial, " she says.
【C15】
选项
A、necessity
B、must
C、need
D、had
答案
C
解析
“you’d”中的’d=would,后面应跟原形动词;must是情态动词,只有need符合题意,可以跟不定式短语(need也可以作情态动词,但此处不是)。故选C。
转载请注明原文地址:https://kaotiyun.com/show/HILd777K
本试题收录于:
职称英语理工类B级题库职称英语分类
0
职称英语理工类B级
职称英语
相关试题推荐
NaturalMedicinesSinceearliestdays,humanshaveusedsomekindsofmedicines.Weknowthisbecausehumanshavesurvived.
CulturalDifferencesPeoplefromdifferentculturessometimesdothingsthatmakeeachotheruncomfortable,sometimeswithou
CulturalDifferencesPeoplefromdifferentculturessometimesdothingsthatmakeeachotheruncomfortable,sometimeswithou
CulturalDifferencesPeoplefromdifferentculturessometimesdothingsthatmakeeachotheruncomfortable,sometimeswithou
CulturalDifferencesPeoplefromdifferentculturessometimesdothingsthatmakeeachotheruncomfortable,sometimeswithou
CulturalDifferencesPeoplefromdifferentculturessometimesdothingsthatmakeeachotheruncomfortable,sometimeswithou
CulturalDifferencesPeoplefromdifferentculturessometimesdothingsthatmakeeachotheruncomfortable,sometimeswithou
TheboysoldgoodsfromdoortodoorbecauseDr.Kellygavespecialattentiontothecasemainlybecause
InitiallythewriterdidnotwanttobuyahearingaidbecauseAccordingtothepassage,hearinglossis
GrossNationalHappinessInthelastcentury,newtechnologyimprovedthelivesofmanypeopleinmanycountries.However,on
随机试题
硫氧嘧啶类抗甲状腺药可以抑制____________酶而抑制甲状腺激素的____________,碘化物抑制____________酶,从而抑制甲状腺激素____________。
患者女,23岁,鼻塞、鼻痒、喷嚏、清涕3年,常年性发作,对生活质量影响较大,近来有胸闷、咳嗽3个月。查体:鼻中隔稍左偏,鼻黏膜苍白水肿,大量水样分泌物。若患者变应原皮肤试验尘螨强阳性,鼻分泌物涂片中发现大量嗜酸性粒细胞。以下可选择的治疗方法包括
下述哪项是输卵管结扎的禁忌证
案情:被告人:胡某,男,15岁,某县中学学生。2001年9月21日下午,胡某和其同班同学刘某五人在本县一铁道路口玩耍。约3时许,一列旅客列车从远处开来。胡随即准备一些石块、砖块,并告诉同学他要向列车投掷。刘某等四人正在铁道旁一空地上打扑克牌,没有人理会胡。
土地补偿费和安置补助费的总和不得超过土地被征收前三年平均年产值的()倍。
个人耐用消费品贷款起点一般为人民币2000元。最高额不超过()万元。
根据支付结算法律制度的规定,下列关于预付卡使用规定的表述中正确的有()。
温室效应
请根据以下各小题的要求设计VisualBasic应用程序(包括界面和代码)。(1)在名称为Forml的窗体上画一个文本框,名称为Text1,内容为“VB程序设计”;再画两个命令按钮,其名称分别为Command1和Command2,标题分别为“扩
[A]camera[B]television[C]watch[D]umbrella[E]breakfast[F]dictionary[G]newspaperPeoplewearitto
最新回复
(
0
)