A
Ever since theunguentari (古罗马时期玻璃器皿) pliedtheir trade in ancient Rome, perfumers have to keep abreast of changingfashions. These days they have several thousand ingredients to choose from whencreating new scents, but there is always demand for new combinations. Thebigger the 'palette' of smells, the better the perfumer's chance of creatingsomething fresh and appealing. Even with everyday productssuch as shampoo andsoap, kitchen cleaners and washing powders, consumers arebecoming increasinglyfussy. And many of today's fragrances have to survivetougher treatment than everbefore, resisting the destructive power of bleachor a high temperature washcycle. Chemists can create new smells from syntheticmolecules, and a growingnumber of the odours on the perfumer's palette areartificial. But nature hasbeen in the business far longer.
B
The island ofMadagascar (马达加斯加) is anevolutionary hot spot;85% of its plants are unique, making it an ideal sourcefor novel fragrances.Last October, Quest International, a company that developsfragrances foreverything from the most delicate perfumes to cleaning products,sent anexpedition to Madagascar in pursuit of some of nature's most novelfragrances.With some simple technology, borrowed from the pollution monitoringindustry,and a fair amount of ingenuity, the perfume hunters bagged 20 promisingnewaromas in the Madagascan rainforest. Each day the team set out fromtheir"hotel"-a wooden hut lit by kerosene lamps, and trailed up anddownpaths and animal tracks, exploring the thick vegetation up to 10 metersoneither side of the trail. Some smells came from obvious places, often bigshowyflowers within easy reach. Others were harder to pin down. “Often itwas the very small flowersthat were much more interesting,” says Clery.After the luxuriance (肥沃) of the rainforest, thelittle-known island of Nosy Hara was astark, dry place-geologically andbiologically very different from themainland. “Apart fromtwo beaches, therest of the island is impenetrable, except by hacking through the bush,"says Clery. One of the biggest prizes here was a sweet-smellingsap weeping fromthe gnarled branches of some ancient shrubby trees in the parched interior. Sofar no one has been able to identify the plant.
C
With most flowers orfruits, the huntersused a technique originally designed to trap and identifyair pollutants. Thetechnique itself is relatively simple. A glass bell jar orflask is fitted overthe flower. The fragrance molecules (分子) are trapped inthis ‘headspace’and can be extracted by pumping the air out over a seriesof filterswhich absorb different types of volatile molecules. Back home inthelaboratory, the molecules are flushed out of the filters and injected intoagas chromatograph for analysis. If it is impossible to attach theheadspacegear, hunters fix an absorbent probe close to the source of the smell.Theprobe looks something like a hypodermic syringe, except that the 'needle'ismade of silicone rubber which soaks up molecules from the air. After afewhours, the hunters retract the rubber needle and seal the tube, keepingtheodour molecules inside until they can be injected into the gas chromatographinthe laboratory.
D
Some of the mostpromising fragrances werethose given off by resins (树脂) that oozed from the bark (树皮) of trees. Resins are the source of many traditionalperfumes,including frankincense and myrrh (乳香和没药). Themost exciting resin came from a Calophyllum (胡桐)tree,which produces a stronglyscented medicinal oil. The sap of this Calophyllumsmelt rich and aromatic, alittle like church incense. But it also smelt ofsomething like fragranceindustry has learnt to live without, castoreum (海狸香)， a substanceextracted from the muskglands of beavers and once a key ingredient in manyperfumes. The company doesnot use animal products any longer, but it waswonderful to find a tree with ananimal smell.
E
The group also set outfrom the island tocapture the smell of coral reefs. Odors that conjure up sunkissed seas arehighly sought after by the perfume industry. “ Fromthe ocean, the only thing we have is seaweed (海带)， and that has a dark and heavy aroma.We hope to find somethingunique among the corals,” says Dir. The challengefor the hunters was to extract a smell fromwater rather than air. This was anopportunity to try Clery’s new “aquaspace”apparatus (小装置) – a set of filters that work underwater. On Nosy Hara,jars werefixed over knobs of coral about 2 meters down and water pumped outover theabsorbent filters. So what does coral smell like? “It’s a bit likelobster and crab,” says Clery. The team’s task now is to recreate the bestof their captured smells. Firstthey must identify the molecules that make upeach fragrance. Some ingredientsmay be quite common chemicals. But some may becompletely novel, or they may betoo complex or expensive to make in the lab.The challenge then is to conjureup the fragrances with more readily availablematerials. “We can avoid the need to importplants from the rainforest bycreating the smell with a different set ofchemicals from those in the originalmaterial, ”says Clery. "If we get it right, you can sniff the sampleandit will transport you straight back to the moment you smelt it intherainforest. "
Question 14-18
The reading Passagehas five paragraphs A-E
Which paragraphcontains the followingdetails?
Write the correctletter A-E in boxes 14-18on your answer sheet.
NB You may use anyletter more than once.
14. One currentlypreferred spot to pick upplants for novel finding
15. A new task seemsto be promising yetproducing limited finding in fragrance source
16. The demandingconditions for fragranceto endure.
17. A substitute forsubstance no longeravailable to the perfume manufacture
18. Description of anoutdoor expedition onland chasing new fragrances.
Question 19-23
Do the followingstatements agree with theinformation given in Reading Passage 2?
In boxes 19-23 on youranswer sheet, write
TRUE if the statementis true
FALSE if the statementis false
NOT GIVEN if theinformation is not givenin the passage
19. Manufacturers canchoose to usesynthetic odours for the perfume nowadays.
20. Madagascar is chosento be a place forhunting plants which are rare in other parts of the world.
21. Capturing thesmell is one of the mostimportant things for creating new aromas.
22. The technique thehunters used to trapfragrance molecules is totally out of their ingenuity.
23. Most customersprefer the perfume madeof substance extracted from the musk glands of animals.
Question 24-26
Filling the blanks andanswer the questionsbelow with only one word.
A simple device usedto trap molecules
结构：
A段：介绍香气背景以及强调原料重要
B段：马达加斯加产香的优势及QI公司前往此处寻香
C段：提取香气原理
D段：从树脂提取能取代动物香气的成分
E段：前往海底捕获珊瑚香并重组创新所获得的香气
答案：
14.B 15.E 16.A 17.D 18.B 19.true 20. true
21.not given 22.false 23. not given 24.headspace
25.filters 26.needle
3.leister 剧院设计
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发表于 2020-12-23 20:41:37
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