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1.
ntroductionArsenic,ametalloid,isanonessentialtraceelement,hasbeenclaimedtobeofclinicalbenefitinthetreatmentofsyphilis,amoebiasisandothertropicaldiseases(Klaassen,1990;Kowaguchi,1981).Besideitsclinicalimportance,arsenicisreportedtobeanimportantwaterpo…  相似文献   

2.
IntroductionRecently,someinstallationswithspecialconstructionforextractingcontaminantgas,suchasanexhausttoweroftheundergroundtunnel,etc.weresetupinurbanandindustrialcomplexareas.Theeffectsoftheseconstructionsontheflowandtherebyonthelocaldispersionoft…  相似文献   

3.
IntroductionThesolid/fluidtwophaseflowsareoftenencounteredinmanyenvironmental,chemicalandhydraulicengineering,suchassedimenttransportationinrivers,wastewaterflowwithsolidparticlesandsoon.Recently,considerableeffortsregardingnumericalpredictionshaveb…  相似文献   

4.
IntroductionTechnologytransfer,orextension(atthelocallevel),istheprocessofmovinginnovationsfromtheirorigintotheirpointofoperation.Innovationsmayincludescientificandtechnicalknowledge,ideas,services,inventionsandproducts.Technologyadoptionistheimpleme…  相似文献   

5.
1 IntroductionElectroplatingsludge,containingCu,Ni,Zn,Cr,Fe,etc.,isharmfulwastematerialproducedbygalvanizationindustry.Thereisstillnoeffectivemethodtorecoverresourceandcontrolpollutionbothathomeandabroad.Themetalsdiscardedbygalvanizationindustryamoun…  相似文献   

6.
New approaches to characterizing urban air particles in central London   总被引:2,自引:0,他引:2  
1 IntroductionOnaninternationalscale,thenatureofurbanairpollutionhaschangedsignificantlyoverthelast50years.Inthe1950sand1960s,themostimportantenvironmentalhealthissuesstemmedfromtheoccurrenceofurbansmogs,anatmosphericcocktailcharacterizedbyhighconcen…  相似文献   

7.
Integrated environmental assessment: an urban perspective   总被引:2,自引:0,他引:2  
1 IntroductionUrbanareasthroughouttheworldareincreasinglyafocusofenvironmentalconcern.Theyareplacesofintenseandgrowingeconomicactivity.Inresponse,urbanpopulationsaregrowingrapidly.Itisestimatedthat,by2000,morethanhalftheworld○spopulationwillliveintow…  相似文献   

8.
Whenchromiteisrefinedtoproducesilicoferrochromealloy,akindofslagcontainingchromiumisformed,knownasferrochromeslag.Itconsistsofmainlycalciumoxide,siliconbioxideandafewbichromiumtrioxide.Becauseofit○slargeproductionandalsobecauseitcontainsharmfulCr6+w…  相似文献   

9.
1 IncreasingenvironmentalproblemscallfortechnologicalsolutionsWiththerapideconomicgrowthinthepasttwodecades,allthemajorenvironmentalproblemsofworldwideconcernhaveappearedinChinainonewayoranother.Theyaremainlyreflectedinsoilerosion,desertification,bi…  相似文献   

10.
IntroductionInrecentyears,moreandmoreevidencesshowthatgreenhousegasesemissionshavebeguntoinfluenceglobalclimate.Greenhouseeffectisoneofthemostrigorouschallengesnowadaysweface.Sincebothcauseandimpactofclimatechangeareglobal,thewholeworldshouldtakeacti…  相似文献   

11.
1IntroductionLandscapeecologyfocusesonstructure,function,andchangesinlandscape(Forman,1986).Heterogeneityinlandscapesisshaped...  相似文献   

12.
IntroductionInmosthigherplantsthesynthesisandaccumulationofbetaineunderstresscondition(saltordrought)hasimportantphysiologicalsignificance(Greenway,1980;Hanson,1978;Storey,1977;Wyn,1977;1978;Hatz,1980).Thereweremanystudiesonthechangeinbetainelevelsin…  相似文献   

13.
1 Sustainableurbandevelopment—thepublichealthdimensionTownsandcitiesarecurrentlythefocusforeconomicplanninganddevelopmentinEuropeancountries.Formerly,politiciansandplannersprioritizedinternationalandnationallevels,withmacroeconomicdevelopmentseenast…  相似文献   

14.
1 IntroductionUrbansustainabledevelopment,populationandGDPproduction,traffic,andenvironmentareinteractingwitheachother.Productionofpopulationandgoodsraisetheneedforexchangeinspace,leadingtotrafficflow.Thetrafficflow,inreverse,furtherenhancetheproduct…  相似文献   

15.
objectiveofcouplingshouldbedecidedbecausethefactorsofwaterandlandresourceshavevariedefectsondiferentpurposes,forexample,tobui...  相似文献   

16.
1 Introduction1-1 DiatomsDiatoms(ClassBacillariophyceae)arecommonandwidelydistributedinbothfreshandmarinewaters(Moser,1996).ThesemicroscopicunicellularplantsfixamajorportionoftheEarth○scarbon,generateoxygen,andsupplyfoodtoanimalswhichfeedonthem(Dixit…  相似文献   

17.
1IntroductionAerosolsplayanimportantroleinclimatechange,airquality,aciddeposition,visibilityreduction,andcloudproceses.Theyar...  相似文献   

18.
IntroductionIncreasedagriculturalproductivityoverthepast50—100yearshasledtoincreasedatmosphericconcentrationsofCO2,CH4andN2O.Thesegases,alongwithadditiontracegasspecies(greenhousegases)arecausinganincreaseinglobaltemperaturesandozonedepletion(Aselman…  相似文献   

19.
IntroductionIodineisanessentialtraceelementcomposingthyroxinthatisofgreatimportanceforthegrowthofhumanbody.Ithasbeenknownthatthedeficiencyofiodineisamajorcauseforanimpedimentofbrainpower.Duringthefetusandbabygrowing,ifsuppliedadeficientiodine,theywil…  相似文献   

20.
IntroductionBleachingwastewaterfrompulppaperplantscontainsmanykindsofchlorinatedorganiccompoundswhichareprovedtobecarcinogenic,mutagenicandrefractory(Gellman,1988;Paasivirta,1988;Garden,1990;Suntio,1988;Vuorinen,1987;Seppala,1988).Severalmethods,inc…  相似文献   

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