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简介：Allplantsemitawiderangeofvolatilecompounds,theso-calledbiogenicvolatileorganiccompounds(BVOC).BVOCemissionshavereceivedincreasedscientificattentioninthelasttwodecadesbecausetheymayprofoundlyinfluencethechemicalandphysicalpropertiesoftheatmosphere,andmaymodulateplanttolerancetoheat,pollutants,oxidativestressandabioticstresses,andaffectplant-plantandplant-insectinteractions.Urbanforestrymayhaveahighimpactonatmosphericcomposition,airquality,environment,andqualityoflifeinurbanareas.However,fewstudieshavebeencarriedoutwheretheemissionofBVOCcouldhaveimportantconsequenceforthequalityofairandcontributetopollutionepisodes.AscreeningofBVOCemissionbythemixedstandconstitutingurbanforestsisthereforerequiredifemissionsaretobereliablypredicted.Monitoringtheemissionratessimultaneouslywithmeasurementsofairquality,plantphysiologyandmicrometeorologyonselectedurbanforests,willallowdetailedquantitativeinformationontheinventoryofBVOCemissionsbyurbanvegetationtobecompiled.Thisinformationwillmakeitpossibletoproposeaninnovativemanagementofurbanvegetationincitiescharacterisedbyheavyemissionsofanthropogenicpollutants,aimingattheabatementofBVOCemissionsthroughtheintroductionorselectionofnon-BVOCemittingspeciesinurbanareassubjectedtopollutionepisodesandinthenewafforestationareascoveringperi-urbanparks,greenbeltsandgreencorridorsbetweenperi-urbanruralareasandtheconurbations.

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简介：Manystudiesindicatedthattheproductsofbiosphereburninghaveshortandlong-termeffectsontheatmosphere.Vegetationburningcanproducesomegaseswhichhavesignificantinfluenceonenvironment,includingsomegreenhousegasesasCO2andCH4,etc.Smokeaerosolsproducedfromburningalsoinfluenceglobalclimateandatmosphericchemistry.Thepapercalculatestheconsumedbiomassduetoforestfiresaccordingtothestatisticsofforestfiresfrom1991to2000andresearchresultsofbiomassofChineseforests.Duringthestudyperiod,forestfiresburnedaverage5Tg-7Tgbiomasseachyearanddirectlyemitted20.24Tg-28.56Tgcarbon.In1991-2000,averageemissionofcarbondioxideandCH4accountfor2.7%-3.9%and3.3%-4.7%ofthetotalemissionofChina(calculatingwiththedataof2000),respectively.

简介：Inordertounderstandtherolesofmomentumdependentinteraction(MDI)onthenucleonemissionduetothecouplingbetweentheisospindependenceofthetwo-bodycollisionsandtheMDIwestudiedthefollowingvariations:△N_n(△σ,U_1~(sym))and△N_p(△σ,U_1~(sym))inthetimeevolutionprocesswiththeMDIandwithoutit(NOMDI).Quantitatively,wedefnine

简介：Electricalemission(EM)signals,whicharegeneratedfromtheconcretespecimensunderthree-pointbendingtests,wereconducted.Itisshownthatelectricalemissionphenomenaarerelatedtocrackingofthespecimens,cohesivefailure,contact-separationetc.Thesimultaneousappearanceofelectricemissionsignalsandvisiblecracksduringtheflexureloadingofbeamswasalsoobserved.

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简介：<正>OnDec.22,EnvironmentSecretaryMargaretBeckettwelcomedaUK/Chinalandmarkagreementonthedevelopmentofcleancoaltechnologywithcarbondioxidecaptureandstorage,whichaimstoreducesignificantlytheclimatechangeimpactfromcoal-firedelectricitygeneration.

简介：Fig.1showstheimpactparameter-averagedasymptoticvaluesofN_nandN_pi.e.b(leftwindow)andb(rightwindow)asafunctionoftheneutron-protonratioofthecollidingsystemwiththesametargetmassandthesameprojectilemassforsixcollidingsystems:~(74)Kr+~(74)Se,~(74)Se+~(74)Se,~(74)Ge+~(74)Se,~(74)Ge+~(74)Ge,

简介：为本地人的明确的表情，即时没有生产率模型被建议不在狂暴的甲烷空气模仿形成燃烧。混合部分和分级的驱散的平均生产率通过二单个变量的概率密度功能的近似从渐近线被获得。理论在theoxygen消费地区从氧化氩氮的机制从Zel-dovich机制，而是可以忽略的贡献预言了重要贡献。建议模型被用来不在pilotmethane空气喷气散开燃烧模仿形成。模拟结果与CFD软件获得的那些相比是流畅的模块。有USA的SandiaNational实验室给的试验性的数据的预言的确认显示建议模型比另外的模型产出更好的结果，并且偏差不到5%。并且在一些完全反应地区，模拟结果与试验性的数据一样是平的。压力模型和standardk-ω建模的雷纳德可实现的k-ε模型也被调查预言狂暴的燃烧反应，它证明模拟由ω模型根据试验性的数据的标准k-燃烧生产的速度，温度，和集中结果。

简介：Fig.1showstheimpactparameter-averagedasymptoticvaluesofthenumberoftheemittedneutronsN_nandthenumberoftheemittedprotonsN_p(whenthevaluesofN_pandN_natt=200fm/cbecomenearlyconstants)i.e.b(topwindow)andb(bottomwindow)asafunctionofthebeamenergywithmomentumdependentintractionforthesystems~(76)Kr+~(40)Ca(leftwindows)and~(76)Kr+~(76)Kr(rightwindows)infivecases:

简介：AfieldexperimentwasconductedonChinesecabbage(BrassicacampestrisL.ssp.pekinensis(Lour.)Olsson)inaNanjingsuburbin2003.Theexperimentincluded4treatmentsinarandomizedcompleteblockdesignwith3replicates:zerochemicalfertilizerN(CK);ureaatratesof300kgNha-1(U300)and600kgNha-1(U600),bothasbasalandtwotopdressings;andpolymer-coatedureaatarateof180kgNha-1(PCU180)asabasalapplication.Theacetyleneinhibitiontechniquewasusedtomeasuredenitrification(N2+N2O)fromintactsoilcoresandN2Oemissionsintheabsenceofacetylene.ResultsshowedthatcomparedtoCKtotaldenitrificationlossesweresignificantlygreater(P≤0.05)inthePCU180,U300,andU600treatments,whileN2OemissionsintheU300andU600treatmentsweresignificantlyhigher(P≤0.05)thanCK.IntheU300andU600treatmentspeaksofdenitrificationandN2OemissionwereusuallyobservedafterNapplication.Inthepolymer-coatedureatreatment(PCU180)duringtheperiod20to40daysaftertransplanting,higherdenitrificationratesandN2Ofluxesoccurred.Comparedwithurea,polymer-coatedureadidnotshowanyeffectonreducingdenitrificationlossesandN2OemissionsintermsofpercentageofappliedN.Astemperaturegraduallydecreasedfromtransplantingtoharvest,denitrificationratesandN2Oemissionstendedtodecrease.Asignificant(P≤0.01)positivecorrelationoccurredbetweendenitrification(r=0.872)orN2Oemission(r=0.781)fluxdensitiesandsoiltemperatureintheCKtreatmentwithastablenitratecontentduringthewholegrowingseason.

简介：Undercoronalconditions,thesteadystaterate-equationsareusedtocalculatetheinter-stagelineratiosbetweenLi-likels22p(2p3/2)→ls22s(2S1/2)andHe-likels2p(1P1)→ls2(1So)transitionsforTiintheelectronictemperaturerangesfrom0.1kevto20keV.Theresultsshowthatthetemperaturesensitivitiesarehigherattheelectronictemperaturelessthan5000eVandthetemperaturesensitivitieswilldecreasewiththeincreaseofelectronictemperature.