老師題源報(bào)精讀課第四課

1、第 6 篇 -科學(xué)類（選自衛(wèi)報(bào) 2014 年 11 月）P344A mirrords heato the frigid expanse of space has been designed byscientists to replace air-conditioning unitst keep buildings cool on Earth.Researchers beve the mirror could slash the amount of energy used to control airtemperatures in business premises and shopcentre

2、s byng away wither-gry cooling systems.Around 15% of the energy used by buildingshe US goes on air conditioning, butthe researchers calculationggestt in somecases, the mirror could compleyoffset the need for extra cooling.In a rooftop comparison of the device in Stanford, California, scientists foun

3、dtwhile a surface paed black reached 60C moren ambient temperature in sunlight,and bare aluminium reached 40C more, the mirror was up to 5C cooler n thesurrounding air temperature.“If you cover significant parts of the roof with this mirror, you can see how mucher it can save. You can significantly

4、offset the electricity used for air conditioning,”said Shanhui Fan, an expert in photonics at Stanford University who led the developmentof the mirror. “In some situations the compuions say you can compley offset the airconditioning.”Buildings warm up in a number of different ways. Hot water boilers

5、 and cookingfacilities release heato their immediate surroundings. In hot countries, warm air comeshrough doors and windows. Then there is visible light and infra-red radiation from thesun, which also heat up buildings.The Stanford mirror was designed in such a wayt it reflects 97% of the visiblelig

6、htt falls on it. But more importantly, it works as a thermal radiator. When themirror is warmed up, it releases heaa specific wavelength of infrared lightt passeseasily through the atmosphere and outo space.To make anything cool requires what engineers call a heat sink: somewhere to dumpunwanted hea

7、t. The heat sink has to be coolern the objectt needs cooling or it willnotts job. For exle, a bucket of ice will cool a bottle of wine because ites asink for heathe liquid. Use a bucket of hot coals and the result will the very different.The Stanford mirror res on the ultimate heat sink: the univers

8、e itself.The mirror is built from several layers ofr-thaterials. Thelayer isreflective silver. On top of this are alternating layers of silicon dioxide and hafnium oxide.These layers improve the reflectivity, but also turn the mirroroa thermal radiator.When silicon dioxide heats up, it radiates the

9、heat as infrared ligha wavelength ofaround 10 micrometres. Since there is very littlehe atmospheret absorbs attwavelength, the heat passes straight out tospace. The total thicknessof the mirror isaround two micrometres, or two thousandths of a millimetre.“The cold darkness of the universe can be use

10、d as a renewable thermodynamicresource, even during the hottest hours of the day,” the scientists write in Nature.ests,the mirror had a coolinger of 40 watts per square metre at ambient temperature.Writinghe journal, Fan puts the installed cost of mirrors at betn $20 and$70 per square metre and calc

11、ulates an annual electricity saving of 100MWh per year ona three storey building.Fan saidt the mirror could cool buildings-or other objectssimply by putting it indirect contact with them. Coating the roof of a building with the mirror would preventheating from sunlight but do little to remove heat f

12、rom itserior. More likely, the mirrorwould be used to cool water or some other fluidt would then be pumped around thebuilding.He ruled out the idea of using the mirrors to slow down global warming. “Roofspace accounts for only a small portion of the Earthrface, so at this powe dontthink this would b

13、e a geoengineering solution. Rather, our contribution on the greenhouse gas emisie is simply to reduce electricity consumption,” he said.“Im really excited by the potential is and the applications for cooling,” saidMarin Soljai, a physicisMIT. “You could use this on buildings so you have to spendmuc

14、h less on air conditioning or maybe you wouldnt need iall. You could put it ontop of shopmalls. Wilarge enough surface you could get substantial cooling.”【詞語積累】frigid adj. 寒冷的premises n. (企業(yè))營業(yè)場所thermal radiator 熱輻射計(jì)infrared adj. 紅外線的silicon dioxide 二氧化硅radiate vt. 放射thermodynamic adj. 熱力的geoenginee

15、ring n. 地球工程學(xué)substantial adj. 大量的【長難句】【參考譯文】科學(xué)家正在設(shè)計(jì)一種可以把熱量傳送到寒冷廣袤太空的鏡面，用來取代為建筑降溫的空調(diào)組。研究認(rèn)為，該技術(shù)可取代商務(wù)場所和購物中心里高能耗的制冷系統(tǒng)，從而大幅降低制冷的能耗。在，空調(diào)耗電量占總建筑物用電量的 15。而研究的計(jì)算結(jié)果表明，該鏡面完全可以抵消對額外制冷電量需求?？茖W(xué)家在加利福尼亞斯坦福大學(xué)的屋頂設(shè)備對比試驗(yàn)中發(fā)現(xiàn)，在光照下，黑面板的表面溫度比環(huán)境溫度高， 鋁面板比環(huán)境溫度高，而鏡面的溫度卻比周圍氣溫低了將近。“如果用鏡面來覆蓋大部分的屋頂，你就知道能節(jié)省多少電量了。這樣做可以有效抵消空調(diào)制冷的耗電量，”

16、該鏡面研發(fā)人、斯坦福大學(xué)光電學(xué)說道?！坝?jì)算結(jié)果證明，在某些情況下，它可以完全抵消空調(diào)制冷的耗電量?！苯ㄖ餃囟壬呤怯啥喾N原因造成的。熱水鍋爐和烹飪設(shè)施向周圍環(huán)境熱量。在氣候炎熱的國家，熱氣透過門窗進(jìn)入室內(nèi)。的可見光和紅外輻射使得室內(nèi)溫度升高。斯坦福大學(xué)設(shè)計(jì)的鏡面可以反射掉 的可見光。但更重要的是，它像一個(gè)熱輻射計(jì)。當(dāng)鏡面溫度升高時(shí)，它能夠通過特定波長的紅外線，輕輕松松把熱量輸送至大氣層和外太空。制冷需要使用熱沉，即吸收多余熱量的設(shè)備。熱沉的溫度應(yīng)低于需制冷物體的溫度，否則制冷無法完成。比如，一桶冰能降低一瓶酒的溫度，因?yàn)楸蔀槠恐幸后w所含熱量的熱沉。如果用一桶燃燒的煤來制冷，效果就會(huì)截然相反

17、。斯坦福研發(fā)的鏡面依靠的就是宇宙這個(gè)終極熱沉。該鏡面由若干層薄片材料制成。第一層是銀反射膜。然后是二氧化硅和氧化鉿交替層。這些涂層能有效提高反射率，同時(shí)把鏡面變成一個(gè)熱輻射計(jì)。二氧化硅溫度升高時(shí)，會(huì)通過約 10 微米波長的紅外線輻射熱量。由于大氣中幾乎沒有物質(zhì)能吸收這一波長的紅外線，因此熱量直接傳送到太空。鏡面的總厚度在 2 微米左右，即千分之二厘米?？茖W(xué)家在自然雜志中撰文寫道：“即使在溫度最高的時(shí)刻，宇宙的寒冷和也可用作可再生的熱力資源?！痹囼?yàn)結(jié)果顯示，室溫下該鏡面的冷卻能力為每平方米 40 瓦特。文章中，估算該鏡面的安裝成本介于每平方米 20 到 70 美金之間，預(yù)計(jì)一棟三層的樓房一年能節(jié)

18、省 100 兆瓦時(shí)的電。說，使鏡面與樓房或其他物體的表面接觸，就能達(dá)到降溫的目的。將鏡面覆蓋到樓頂上，便可有效輻射的熱量。但它對降低室溫作用甚微。鏡面反倒更可能給樓房管道中的水或其他液體降溫。他打消了利用該鏡面技術(shù)延緩全球變暖的念頭?！拔蓓斆娣e只占地球表面的極小一部分，因此認(rèn)為該技術(shù)不能提供地球工程解決方案。鏡面技術(shù)對溫室氣體排放的貢獻(xiàn)，僅僅在于減少耗電量而已?！薄斑@一技術(shù)的發(fā)展?jié)摿捌湓谥评浞矫娴膽?yīng)用令我感到振奮，” 麻省理工學(xué)院物理學(xué)家西克說道?！澳憧梢园惭b在樓頂上，這樣空調(diào)的耗電量會(huì)大大降低，你甚至不需要空調(diào)制冷。你還可以安裝在商場的屋頂。因?yàn)槲蓓斆娣e比較大，將會(huì)看到實(shí)質(zhì)性的制冷效果?！?/p>

19、第 7 篇 -衛(wèi)生類（選自科學(xué) 2015 年 4 月）P250When nature calls, about 1 billion peoplehe develoworld still head to anopen field, the bushes, or a body of water to defecate. The practice has contributed tohigh rates of diarrheal diseases, espelly, where moren half of people dontuse latrines. Prime Minister Narendr

20、a Modi, who tooker last May, has pledged tobuild 111 million toilets as part of the Cleanmis, a saniionn. Onegoal is to end open defecation by October 2019.But exactly how to get there irprisingly controversial. Some nonernmentalanizations andernment offils in develocountries have longpushed foreduc

21、ationnsteaching people about the health benefits of using toilets. Othersadvocate subsidizing latrine costs for the poor, but some economists arguet finanlaid for cheap toilets could backfire by discouraging those who dont receive it frombuying latrines on their own for a highrice.Now, one of the la

22、rgest controlled experiments to examine saniion strategies,conducteds neighbor Bangladesh and published online thisk in Science,comes down strongly in favor of cash. After comparing three policiesoren 100villages, the authors foundt the key to getting people to build latrines is to subsidizethe cost

23、. They also foundt funding poor villagers to install latrines can encouragetheir unsubsidized neighbors to follow suit in a benefil spillover effect.Given the enormous emphasis Prime Minister Modi has placed on eliminating opendefecation, these results should be of greaterest to thenernment. Itls us

24、t cutting the price of quality toilets is the single mosterful instrument ingetting people to stop defecating outside,” says economist Abhijit Banerjee of theMassachusetts Institute of Technology in Cambridge, who was not involvedhe study. Others caution, however,t building toilets doesnt always mea

25、n people will usethem or be healthier, ort findings in Bangladesh will be relevant to culturally different.The experiment, funded by the Bill & Melinda Gates Foundation in Seattle,Washington, took placehe Tanore, a poor, rural district in northwest Bangladesh.Although open defecation rates are only

26、3% overall in Bangladesh,anore, aboutone-third of adults still follow the practice or use unhygienic latrines, such as “hanging”latrinest emptyo waterways. Yale University economists Mushfiq Mobarak andJames Levinsohn and Raymond Guiteras of the University of Maryland, College Park,chose 107 village

27、s with 18,254 poor households. Some villages received education on theimportance of saniion, and some received only information on buying and installing alatrine. In a third program, 25% to 75% of villagers received vouchers through a lottery.Each voucher was good for about 50% off the $29 to $58 co

28、st of an installed pour flushlatrinea designt carries feto a sealed pit.The vouchers made all the difference, the researchers found 13 months later.Education alone or information on how to acquire a latrine did not significantly increasethe portion of people who owned or had acs to a hygienic latrin

29、e. But education plusvouchers resulted in significant changefor exle, a rise in hygienic latrine ownershipfrom 22%he control group to 45% in villages where half the households receivedvouchers and education. The study also found a reduction of 14% in open defecation inthese same villages.The big sur

30、prise wast even people who didnt receive a voucher were moreinclined to buy a latrine at full price if their neighbors received vouchers. This effect wasstronger when a highroportion of households received vouchers. People were alsomore likely to use their vouchers in neighborhoods where more househ

31、olds receivedvouchers. For policymakers, the message is clear, Mobarak says: “If you are going to usesubsidies, it makes sense to allocate them in a coordinated manner sot many people ina community all get subsidies joly.”Varande, an economist with the Dalberg consulting firmumbai,who has advised th

32、enernment and the World B about saniion policies,says the results“resonate with our experience on the ground. Both subsidies andeducation need to happen in a well-orchestrated sequence.” To Sumeet Patil, andemiologist and economist with the Network for Engineering and Economics Researchand Managemen

33、tumbai, the result should settle the debate over toilet subsidies.But others say an encouraging result in Bangladesh may not say much about,where the hygiene problem is much bigger. A survey released last year by theResearch Institute for Compasate Economics (RICE) in New Delhi foundt manyns who hav

34、e acs to a hygienic latrine still prefer open defecation, particularlyHindus, who were not representedhe Bangladesh study. The reasons may involveHindu caste system befst allowing feto accumulate in a latrine is impure andt only an“untouchable” can remove them, says RICEExecutive Director Dean Spear

35、s. He adds:“I would just say we should be verycareful about generalizing to Hindu rural north.”【詞語積累】defecate vi. 排便 diarrheal n. 痢疾 latrine n. 廁所 saniion n. 公共衛(wèi)生install vt. 安裝 spillover effect 溢出效應(yīng) unhygienic adj. 不衛(wèi)生的allocate vt. 分派hygiene n. 衛(wèi)生generalize vi. 普及【長難句】【參考譯文】在發(fā)展中國家，大約有 10 億人仍在空地、叢林甚至水塘邊解決內(nèi)急。這種導(dǎo)致了腹瀉的高，尤其是在，一半以上的人不使用公共廁所。去年五月剛執(zhí)政的首相納倫保證修建 1.11 億個(gè)廁所，以作為“更加清潔”這一衛(wèi)生活動(dòng)的一部分。其中一大目標(biāo)就是在 2019 年 10 月之前終結(jié)露天排泄的行為。但是如何達(dá)到這個(gè)目標(biāo)存在著很大的爭議。一些發(fā)展中國家的非的機(jī)構(gòu)和一直推行教育宣傳活動(dòng)，來告訴人們使用廁所的衛(wèi)生益處。其他人支持為窮人提供修建廁所的。但是一些認(rèn)為對廉價(jià)的廁所提供補(bǔ)貼，可能會(huì)產(chǎn)生事與愿違的效果，因?yàn)檫@會(huì)挫傷那些自己花