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
2015-07-04
32
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.
【C5】
选项
A、no
B、per
C、each
D、every
答案
A
解析
在空格所在句子中,vessels是复数,no既可跟单数名词也可跟复数名词,而其他词都只能跟单数名词。故选A。
转载请注明原文地址:https://kaotiyun.com/show/LzLd777K
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
DangersAwaitBabieswithAltitudeWomenwholiveintheworld’shighestcommunitiestendtogivebirthtounderweightbabie
NewU.S.PlanforDiseasePreventionUrgingAmericanstotakeresponsibilityfortheirhealth,HealthandHumanServicesSe
Hisclaimsseemcredibletomanypeople.
NaturalMedicinesSinceearliestdays,humanshaveusedsomekindsofmedicines.Weknowthisbecausehumanshavesurvived.
NaturalMedicinesSinceearliestdays,humanshaveusedsomekindsofmedicines.Weknowthisbecausehumanshavesurvived.
CulturalDifferencesPeoplefromdifferentculturessometimesdothingsthatmakeeachotheruncomfortable,sometimeswithou
CulturalDifferencesPeoplefromdifferentculturessometimesdothingsthatmakeeachotheruncomfortable,sometimeswithou
SeekHealthandWellness1Whetheryouarebusystudyingorstartingclerkship,itisabsolutelyessentialtomaintainhealthand
Theirstyleofplayingfootballisutterlydifferent.
Readingthejobad,hewonderedwhetherhewaseliqibletoapplyforit.
随机试题
某工业园区引入一中外合资经营投资项目。项目投资总额(含增值税)为8000万美元,其中建筑工程费10000万元,安装工程费3000万元,工程建设其他费用5500万元,预备费3500万元。合资公司注册资本占投资总额的40%,由中外双方按6:4的股份比例出资。注
“目标”是产生动机的什么因素?
Itwasanearlymorninginsummer.Inthestreets,sleepy-eyedpeopleweremovingquickly,headingtowardstheir【61】.Thiswast
Ifwomenaremercilesslyexploited(剥削)yearafteryear,theyareonlythemselvestoblame.Becausetheytrembleatthethoughtof
DearDr.Benjamin,CongratulationsonyournominationasUnitedStatesSurgeonGeneral.Basedonyourextraordinarycareera
A.阴道外出血量和贫血程度不一致伴腹痛B.阴道流血性黏液C.无痛性反复阴道出血D.分娩阻滞形成病理缩复环,伴少量阴道出血E.分娩阻滞,剧烈腹痛后宫缩停止,病情恶化前置胎盘
两步滴定法测定阿司匹林片剂含量亚硝酸钠滴定法测定对氨基水杨酸钠的含量
按照保险利益原则,下列当事人的投保行为无效的是( )。
以下关于增量模型的叙述中,正确的是()。
HappinessisU-shaped,forwearehappieratthestartandendofourlivesbuthitaslumpwhenweare【C1】______,BritishandU
最新回复
(
0
)