A)TheweatherreportontheradioorTVtellsyouthatitisgoingtobesunnyandhotandthatanorangeozonealerthasbeenissued.Whatisozone?Whatdoesanorangealertmean?Whyshouldyoubeconcernedaboutit?Inthisarticle,wewillexaminewhatozoneis,howitisproduced,whathealthhazardsitposesandwhatyoucandotoreduceozonepollution.
B)Ozoneisamoleculeofthreeoxygenatomsboundtogether(O3).Itisunstableandhighlyreactive.Ozoneisusedasableach,adeodorizingagent,andasterilizationagentforairanddrinkingwater.Atlowconcentrations,itistoxic.Ozoneisfoundnaturallyinsmallconcentrationsinthestratosphere,alayerofEarth’supperatmosphere.Inthisupperatmosphere,ozoneismadewhenultravioletlightfromthesunsplitsanoxygenmolecule(O2),formingtwosingleoxygenatoms.Ifafreedatomcollideswithanoxygenmolecule,itbecomesozone.Stratosphericozonehasbeencalled“good”ozonebecauseitprotectstheEarth’ssurfacefromdangerousultravioletlight.
C)Ozonecanalsobefoundinthetroposphere,thelowestlayeroftheatmosphere.Troposphericozone(oftentermed“bad”ozone)isman-made,aresultofairpollutionfrominternalcombustionenginesandpowerplants.Automobileexhaustandindustrialemissionsreleaseafamilyofnitrogenoxidegases(NOx)andvolatileorganiccompounds(VOC),by-productsofburninggasolineandcoal.NOxandVOCcombinechemicallywithoxygentoformozoneduringsunny,high-temperatureconditionsoflatespring,summerandearlyfall.Highlevelsofozoneareusuallyformedintheheatoftheafternoonandearlyevening,dissipatingduringthecoolernights.
D)Althoughozonepollutionisformedmainlyinurbanandsuburbanareas,itendsupinruralareasaswell,carriedbyprevailingwindsorresultingfromcarsandtrucksthattravelintoruralareas.Significantlevelsofozonepollutioncanbedetectedinruralareasasfaras250milesdownwindfromurbanindustrialzones.
E)Youcanmakeozoneteststripstodetectandmonitorozonelevelsinyourownbackyardoraroundyourschool.Youwillneedcornstarch,filterpaper(coffeefiltersworkwell)andpotassiumiodide(canbeorderedfromascienceeducationsuppliersuchasCarolinaBiologicalSupplyorFisherScientific).Basically,youmakeapastefromwater,cornstarchandpotassium-iodide,andyoupaintthispasteonstripsoffilterpaper.Youthenexposethestripstotheairforeighthours.Ozoneintheairwillreactwiththepotassiumiodidetochangethecolorofthestrip.Youwillalsoneedtoknowtherelativehumidity,whichyoucangetfromanewspaper,weatherbroadcastorhomeweatherstation.
F)Whenyouinhaleozone,ittravelsthroughoutyourrespiratorytract.Becauseozoneisverycorrosive,itdamagesthebronchiolesandalveoliinyourlungs,airsacsthatareimportantforgasexchange.Repeatedexposuretoozonecaninflamelungtissuesandcauserespiratoryinfections.
G)Ozoneexposurecanaggravateexistingrespiratoryconditionssuchasasthma,reduceyourlungfunctionandcapacityforexerciseandcausechestpainsandcoughing.Youngchildren,adultswhoareactiveoutdoorsandpeoplewithrespiratorydiseasesaremostsusceptibletothehighlevelsofozoneencounteredduringthesummer.Inadditiontoeffectsonhumans,thecorrosivenatureofozonecandamageplantsandtrees.Highlevelsofozonecandestroyagriculturalcropsandforestvegetation.
H)Toprotectyourselffromozoneexposure,youshouldbeawareoftheAirQualityIndex(AQI)inyourareaeveryday—youcanusuallyfinditinthenewspaperoronamorningweatherforecastonTVorradio.YoushouldalsobefamiliarwiththeU.S.EnvironmentalProtectionAgency(EPA)guideforozone-alertvalues.
I)WhatdothenumbersintheAQImean?TheAQImeasuresconcentrationsoffiveairpollutants:ozone,sulfurdioxide,particulatematter,carbonmonoxideandnitrogendioxide.TheEPAhaschosenthesepollutantsascriteriapollutants,butthesearenotallofthepollutantsintheair.Theseconcentrationsarecomparedtoastandardsetoutinfederallaw.Anindexvalueof100meansthatallofthecriteriapollutantsareatthemaximumlevelthatisconsideredsafeforthemajorityofthepopulation.Toreduceyourexposuretoozone,youshouldavoidexercisingduringafternoonandearlyeveninghoursinthesummer.
J)Thereareseveralwaysyoucanhelptodecreaseozonepollution.Limitusingyourautomobileduringafternoonandearlyeveninghoursinthelatespring,summerandearlyfall.Donotusegasoline-poweredlawnequipmentduringthesetimes.Donotfuelyourcarduringthesetimes.Donotlightfiresoroutdoorgrillsduringthesetimes.Keeptheengineofyourcarorboattuned.Makesurethatyourtiresareproperlyinflated.Useenvironmentallysafepaints,cleaningandofficeproducts(someofthesechemicalsaresourcesofVOC).
K)Besidespersonalattemptstoreduceozonepollution,theEPAhasinitiatedmorestringentair-qualitystandards(suchastheCleanAirActanditsmodifications)toreduceairpollution.Compliancewiththesestandardsbyindustries,manufacturersandstateandlocalgovernmentshassignificantlyreducedthelevelsofmanycommonairpollutants.
L)Withcontinuedconservationandreductionpractices,adherencetoozone-pollutionwarnings,researchandgovernmentregulation,ozone-pollutionlevelsshould
continuetofall.Perhapsfuturegenerationswillnotbethreatenedbythisenvironmentalpollutant.
M)Thethingthatdetermineswhetherozoneisgoodorbadisitslocation.Ozoneis‘‘good,,whenitisinthestratosphere.Thestratosphereisalayeroftheatmospherestartingatthelevelofabout6miles(about10kilometers)abovesealevel.Thestratospherenaturallycontainsaboutsixpartspermillionofozone,andthisozoneisverybeneficialbecauseitabsorbsUVradiationandpreventsitfromreachingus.
N)Ozoneis“bad”whenitisatgroundlevel.Ozoneisaveryreactivegasthatishardonlungtissue.Italsodamagesplantsandbuildings.Anyozoneatgroundlevelisaproblem.Unfortunately,chemicalsincarexhaustandchemicalsproducedbysomeindustriesreactwithlighttoproducelotsofozoneatgroundlevel.Incities,theozonelevelcanrisetoapointwhereitbecomeshazardoustoourhealth.That’swhenyouhearaboutanozonewarningonthenews.
1.Whenultravioletraysfromthesunseparateanoxygenmoleculeintotwosingleoxygenatomsinthestratosphere,thecombinationofasingleoxygenatomandanoxygenmoleculeformsozone.
2.Youcanmakeozoneteststripsbyyourselftofindoutaboutozonelevelsinyourownlocale.
3.Long-timeexposuretoozoneisbadlyharmfultoourrespiratorysystem.
4.Chemicalsinindustrialwastegasandvehicleexhaustreactwithlighttoformlotsofozoneatgroundlevel.
5.Internalcombustionenginesandpowerplantscausetheartificialtroposphericozone,alsoknownas“bad”ozone.
6.OzoneisveryhelpfulbecauseitabsorbsUVradiationandseparatesusfromit.
7.Usinggasoline-poweredlawnequipmentinthelatespring,summerandearlyfallmayincreaseozonepollution.
8.Ozonepollutionoccursinurbanandsuburbanareasaswellasinruralareas.
9.Inordertodecreaseozonepollution,theEPAhassetupmorerigorousair-qualitystandards.
10.PaycloseattentiontotheAirQualityIndexinyourareaeverydaycankeepyouawayfromozoneexposure.
文章主要介绍了什么是臭氧,臭氧污染的形成、危害,以及臭氧有利的一面。文章还具体介绍了如何自己手工制作检测仪;如何避免暴露在臭氧之下;如何预防和减少臭氧污染等。
1.B本题答案的信息来自B段的倒数第二、三句话。原文中提到太阳紫外线将氧分子分成了两个单独的氧原子,氧原子与氧分子再结合就生成了臭氧。题干正好表达了这个意思。ultravioletrays即是原文中的ultravioletlight。
2.E本题答案的信息来自E段第一句话。题目中的findoutabout意为“弄清有关的情况”,和原文中的detectandmonitor含义相对应;题目中的inyourownlocale和原文中的inyourownbackyard相对应。
3.F本题答案的信息来自F段。F段提到人吸入臭氧后,它可以贯穿你的呼吸系统。接着提到它可能损害细支气管、肺部等呼吸系统的部位,故可知长期暴露在臭氧下有损呼吸系统。
4.N本题答案的信息来自N段第五句话,题干是对本句的同义转述。
5.C本题答案的信息来自C段的第二句话。原句中先说“果”后说“因”,题目将
“因”提前,然后说“果”;原文中的man-made与题干中的artificial相对应;原文中的termed与题干中的knownas相对应。
6.M本题答案的信息来自M段第二句和最后一句话。原文中第二句话首先提到
Ozoneis“good”whenitisinthestratosphere.,在最后一句中提到臭氧为什么有益;原文中的beneficial与题干中的helpfUl相对应;题目中的separatesfrom对应原文中的preventsfrom。
7.J本题答案的信息来自J段第一、二、三句话。原文中J段的首句提到有几种可以降低臭氧污染的方法,接下来提到的一种方法是Donotusegasoline-poweredlawnequipmentduringthesetimes.由此推测Usinggasoline-poweredlawnequipment会导致臭氧污染增加;而由第二句话可推测出原文中的duringthesetimes指的是inthelatespring,summerandearlyfall。
8.D本题答案的信息来自D段第一句话。原文提到臭氧污染主要在城市和城市郊区出现,但因为风和汽车、卡车运输的作用,农村也会发生臭氧污染,题干是对此的归纳。
9.K本题答案的信息来自K段第一句话。原文中的initiated和题目中的setup属于同义转换;原文中的stringent替换为了rigorous;原文中的reduceozonepollution替换为了decreaseozonepollution。
10.H本题答案的信息来自H段第一句话。题目中的keepyouawayfrom对应原文的protectyourselffrom;题目中的Paycloseattentionto对应原文的shouldbeawareof。