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简介：以便在不同agro生态的地区在农田上测量灰尘的滋养的输入，非洲西部十二月至三月所吹的寒冷干燥北风灰尘被地席在在20022006之间的迦纳与塑料稻草取样。由在迦纳的非洲西部十二月至三月所吹的寒冷干燥北风灰尘的全部的营养素的输入每非洲西部十二月至三月所吹的寒冷干燥北风时期是大约12kgCa哈1,0.52kgK哈1,0.51.5kgMg哈1和不到0.5kgP哈1。与由降水的营养素的年度输入相比，灰尘Ca，Mg和K，但是近似占了10%或少些P的20%40%。，由灰尘的营养素的输入在区域为有植被的区域仅仅是有效的与没有或稀少的植被，由于风侵蚀并且在此，营养素的损失可能是的土壤的损失重要。在有赤裸、生长的地的农田区域，似乎是营养素的内部再分配和从在区域(远程的搬运灰尘)外面的营养素的并非网获得。当Ca，Mg和K的另外的三营养素的输入是那么低的他们必须被认为不足道时，由灰尘的P的输入可能具有在传统的变耕作系统的某重要性。在有粪肥和化肥的巨大的输入的集中的农业系统，由灰尘的滋养的输入是不足道的并且能被忽视。

简介：Withtheimplementationofreformandopening-up,theoveralleconomyofChinahasmadebrilliantachievements;meanwhile,however,theeconomicdisparityhasbeenenlargingamongsomeregions,andbetweenthecityandthecountryside.Theexistenceandevolutionofthiskindofeconomicdisparityisconcernedwithsocialstability,sustainabledevelopmentandtheconstructionofharmonioussociety,whichhasgraduallybecomethehotspotinsocialeconomicdevelopment.TheWestCoastoftheStrait(WCS)locatedinsoutheastlittoralareasisadjacenttothePearlandYangtzeRiverDeltainthesouthandnorthandfacesTaiwanProvinceintheeast.Thestabilityanddevelopmentofthisregionhasvitalpoliticalandeconomicmeaninginthesocialeco-nomicdevelopmentofourcountry.Ithasimportanttheoreticalmeaningandpracticalvaluetoresearchtheform,characteristicsandevolutionofregionaleconomicdisparityintheWCS.BasedoninsightfulanalysisonexistingstudyresultsontheWCS,thepaperdefinestheconnotationandextension.Byaseriesofabso-luteandcomparativerelativeevaluationindexesandtakingtheWCSsince1992asthestudyobject,thepapermakesanalysisondifferentscalesincludingthreeregions,fourregions,20citiesand152counties,quantitativelyevaluatesthelevel,characteristicsandevolutionoftheregionaleconomicdisparityandcomparestheregionaleconomicdisparityondifferentscales.Themainconclu-sionsareasfollows:thevariationtrendoftheabsolutedisparityofthewholeregionisobviousandstable,whichhaspresentedaninflatingtrend;thecomparativevariationtrendonalargescalehaswaved,Thecomparativedisparityofthethreeregionsin-creasedannuallyfrom1992toaround2000,whichhadadecreas-ingtrendfromaround2000to2005;thecomparativevariationtrendonasmallscalewasnotstable,whichshowedanannualincreaseoffourregions,20citiesand152countiesfrom1992toaround2003andadecreasefromaround2003to2005;ther

简介：ThepaperpresentsthebasicmodelforthetransmissiondynamicsofWestNilevirus(WNV).Themodel,whichconsistsofsevenmutually-exclusivecompartmentsrepresentingthebirdsandvectordynamics,hasalocally-asymptoticallystablediseasefreeequilibriumwhenevertheassociatedreproductionnumber(R0)islessthanunity.Asrevealin[3,20],theanalysesofthemodelshowtheexistenceofthephenomenonofbackwardbifurcation(wherethestabledisease-freeequilibriumofthemodelco-existswithastableendemicequilibriumwhenthereproductionnumberofthediseaseislessthanunity).Itisshown,thatthebackwardbifurcationphenomenoncanberemovedbysubstitutingtheassociatedstandardincidencefunctionwithamassactionincidence.Analysisofthereproductionnumberofthemodelshowsthat,thediseasewillpersist,wheneverR0>1,andincreaseinthelengthofincubationperiodcanhelpreduceWNVburdeninthecommunityifacertainthresholdquantities,denotedby△band△varenegative.Ontheotherhand,increasingthelengthoftheincubationperiodincreasesdiseaseburdenif△b>0and△v>0.Furthermore,itisshownthataddingtimedelaytothecorrespondingautonomousmodelwithstandardincidence(consideredin[2])doesnotalterthequalitativedynamicsoftheautonomoussystem(withrespecttotheeliminationorpersistenceofthedisease).

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简介：TheTheGreat-WestDykewithalengthof6.7km,thelargestseawallinChina,wascompletedinJune,1994.Thispaperintroducesstructureoptionsofnibblemoundseawallonsoftfoundationandanewtypeofarmourblock-hexagonmultiholeblock(HMB)andanewmethodoftreatmentforsoftfoundationbyusingunderwaterexplosion.ConstructionpracticeofsomeprojectsinChinashowsthatbyusingthismethodgoodeffectoftreatmentandmarkedeconomicbenefitcanbeachievedbyusingthismethod.

简介：Passingonemonthcontinuoustrialoperation,the500kVHVDCtransmissionprojectfromTianshengqiaoHydropowerStationtoGuangzhouwascommissionedonDecember26,2000.ThisindicatesathirdbulkpowerchannelfromwesttoeastandthefirsthybridsystemofHVDCandHVACparalleloperationinChina

简介：利用生态脆弱度的灰色评判法建立了沙质荒漠化的干扰－应变关系，进而求算了不同荒漠化程度样地的生态脆弱度，结合气候、地貌、植被、土壤等特征指标对东北西部沙质荒漠化地区土地荒漠化作出评价：该区的土地沙质荒漠化可分为强度沙漠化、中度沙漠化、轻度沙漠化、微度沙漠化、潜在沙漠化五个级别，各等级及其相应的生态脆弱性、植被群落多样性、群落稳定性等指标可用于中小尺度的荒漠化土地评价图的绘制，其可作为土地荒漠化防治的重要理论依据．

简介：这份报纸介绍概括Riesz操作符的概念和概括Riesz操作符的西方分解的定义的一个一般操作符的概括韦斯特分解的概念，并且证明下列三个语句在一个一般Banach空格是相等的：(a)每个概括Riesz操作员有概括韦斯特分解；每个操作员使Stampfli强壮的(b)定理真；(c)每个操作员有Apostol鈥檚协议修正。关键词Banach空间-概括Riesz操作员-概括韦斯特分解-紧缩的修正先生(2000)题目分类47A10-47A11-47A53由中国(10471025)的国家自然科学基础支持了，福建省(Z0511019)和福建省(JA04170)的教育系的基础的国家科学基金

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简介：WiththeriseofChina'spositionintheinternationalpoliticalandeconomicfields,theWestbegantoquestionChina'sdevelopingcountrystatus.thewrongperceptionoftheWestliesprimarilyinthefollowingaspects:first,thevaguenessoftheconceptof'developingcountries'andthetendencytowardsnarrowingthenotion;second,thewesterncountriesarepressingChinatoshouldermoreinternationalresponsibilitiesinsodoing.

简介：Thedissolutionofthebipolarworldstructurehasupsettheformerpoliticalbal-anceofpowerinWestern-Europe,whichisnowinastateoftransitionfromtheoldordertoanewone.Atpresent,WesternEuropeisbeleagueredbyconcur-renteconomic,politicalandsocialcrises.Oldandnewcontradictionsareeruptingsimultaneously.Variouspoliticalforcesareintheprocessofdisintegrationandre-

简介：WorkersonOctober29completedatunnelunderChina'sYangtzeRiverforamajorgaspipelinethatwillrunfromthesouthwestprovinceofSichuantoShanghaiineastChina.Withadiameterof3.08metersandalengthof1,405meters,thetunnellaidabout20metersbeneaththeriverbed,connectingtwogaswellsoneachbankoftheYang-

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简介：Basedontheassumptionofglobalsealevelrisingbetween30and100cminthefuture100yearsbyIPCC(1990)inadditiontotheeffectoflocalgroundsubsidence,thecoastlinewillretrogradefor50-70kmwhosealtitudeswillbe2.6-3.3maboveMSLofHuanghaiSeainthewesterncoastalareaoftheBohaibayin2100.Thetransgrassiveareaisabout10,000-11,500km.Iftheeffectofset-upofstormsurgeisconsidered,thetransgressiveareawillreach16,000km.Sealevelrisewhichisaseriouscoastaldisasternotonlyinundatesalotofcoastallowland,butalsoincreasesthefrequencyandintensityofstormtides,andresultsinthesalinizationofsoils.Inviesofthissituationwerecommendatrinitycomprehensivemeasureoftreatment,namely,"buildingseawalltopreventtides-divertingtheHunagheRivertosettleitssedimentloads-raisingtheconstructionalbase".

简介：ThecontrollingandinfluencingeffectsofthejointactionofplatessurroundingChinaonstrongearthquakesinChinesemainlandarediscussed,andthecharacteristicsofseismicactivitiesintheWestofChinaandneighboringregionsarefurtherstudied.TheresultsshowthattheseismicactivityintheWestofChinaandneighboringregionsnotonlyhasthecharacteristicsofhightideandlowtidealternationbutalsohasthecharacteristicsofrisinginoneregionwhilefallinginanother,andtheriseandfailofseismicityareinsomeproportion.TheabovecharacteristicsareusefulforthepredictionofmainbodyregionofstrongearthquakesinChinesemainland,especiallyforthejudgementoftheendingtimeofthehighfideperiod.

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