简介:在布基纳法索,endosulfan的重要数量被用于棉花地;另外,城市的蔬菜农业被高fertiliser输入经常描述,例如包含重金属的城市的稳固的浪费(例如,Cu和Cd)。因此,包围棉花的关联和城市的蔬菜与vetiver(Vetiveriazizanioides)阴谋篱笆由micropollutants减少环境污染用一个沥滤的实验被调查,与充满布基纳法索的二代表性的农业土壤的室外的溶度计:Vertisol和Lixisol。在6个月以后,小Cu在leachates被发现(<0.010%应用数量)由于它的高吸附,在土壤留下的系数和它的趋势出现。尽管有leachate和溴化物恢复,在土壤是更大的比在赤裸的土壤与vetiver种了草,endosulfan和Cd的更小的数量从赤裸的土壤(0.01%~1.48%应用数量)比在那些从种的土壤(0.01%~0.70%应用数量)在自河被发现,与他们的吸附系数一致。这些结果可以被endosulfan的更大的降级也与赤裸的土壤和Cd的吸收相比在种的土壤解释由vetiver。因此,vetiver可以减少地下水污染的风险特别为Cd和endosulfan,它比Cu更活动。另外,尽管有endosulfan和Cd的更小的数量,在Vertisolleachates测量了(0.01%应用数量和0.04%,分别地)与Lixisolleachates相比,vetiver在减少是更有效的micropollutants沥滤如果在Lixisol上而非在Vertisol上种了。进一步的地监视是必要的在布基纳法索的气候的条件下面表明vetiver的有效性。
简介:与无线设备的吊杆,在无线本地区域网络(WLAN)下面的无线用户的数字戏剧性地增加了。然而,在IEEE802.11的标准backoff机制采用没有考虑的尺寸网络负担改变的固定起始的竞争窗户(CW),它在bursty到达导致高碰撞可能性和低隧道利用。在这份报纸,一个新奇CW动态调整计划被建议在笨用户环境完成高产量性能。在建议计划,起始的CW尺寸动态地被适应最佳根据测量的包碰撞概率。模拟结果证明建议计划罐头显著地改进产量表演。
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简介:AnanalyticalsolutionofvelocityprofilesforNon-Newtonianfluidsdescribedbythepower-lawequationinaxiallaminarflowthrougheccentricannuliispresented.Theexpressionsoflimitvelocitiesandcontoursofequalvelocityareobtained.Themainapproaches,claimedinthispaper,arethatthetermTrz/rinthedifferentialequationofflowandthenon-symmetricalvelocitydistributionaboutthegeometriccenteroftheradialclearanceareconsidered.
简介:Thispapermakesthethermodynamicanalysisinforcedconvectiveflowofathirdgradefluidthroughaverticalchannel.Duetothereactivenatureofthefluid,theeffectofinternalheatgenerationisconsideredandassumedtobealinearfunctionoftemperature.ThecouplednonlineardimensionlessordinarydifferentialequationsgoverningthefluidflowaresolvedbyusingtheAdomiandecompositionmethod(ADM).Theeffectsofvariousphysicalparameterssuchasthirdgradematerialparameter,buoyancyparameterandheatgenerationparameteronthethermalstructureofflowarepresentedanddiscussed.
简介:Alargediamondcrystalupto500μmindiameterwithasmooth(100)facetatitstophasbeensynthesizedonMosubstratethroughmicrowaveplasmachemicalvapordeposition(MPCVD).Itsmorphologyandqualitywerecharacterizedbyscanningelectronmicroscopy(SEM),andthegrowthmechanismwasroughlyillustratedfrombothmacroscopicandmicroscopicviewpoints.Itwasfoundthatmorphologicalinstabilitiesareamajorfactorresultinginsynthesisoflargediamondcrystals,moreover,highmicrowavepowerdensity(MPD),highCH4concentrations,highpressure,highsubstratesurfacetemperatureandtheadditionofasmallamountofO2werealsonecessaryforthesynthesisoflargediamondcrystals.
简介:Itisawell-knownfactthatcharactersofafinitegroupcangiveimportantinformationaboutthestructureofthegroup.Itwasalsoprovedbythethirdauthorthatafinitesimplegroupcanbeuniquelydeterminedbyitscharactertable.Heretheauthorsattempttoinvestigatehowtocharacterizeafinitealmost-simplegroupbyusinglessinformationofitscharactertable,andsuccessfullycharacterizetheautomorphismgroupsofMathieugroupsbytheirordersandatmosttwoirreduciblecharacterdegreesoftheircharactertables.
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简介:Lowvoltageridethrough(LVRT)capabilityhasbecomemoreandmoreanissuefornewlyintegratedwindturbines.TheLVRTprogramsdescribedinthispaperdevelopedfieldtestsfornewlyinstalledwindturbinesonwindfarmsinNortheastChina.ItisthereforedifferentfromotherpapersthatonlyvalidateLVRTcontrolstrategiesthroughrunningcomputersoftwaresimulations.Toexamineasinglewindturbine'sLVRTcapability,thewindturbine'sterminalvoltagedipwasrealizedbyusingagridvoltagedipemulator,whichwaslocatedonthe690Vsideofthegeneratortransformer.Inthispaper,byartificiallymakingvariousgridfaults,thedynamicbehaviorofDFIGandPMSGwindturbinesareanalyzedandcompared,controlstrategiessuchasactive/passivecrowbarandchopperprotectionschemesareverified,andnewactive/reactivepowercompensationmethodsareinvestigatedandcompared.
简介:BasedontheopticaldatafortransmittedradiationthroughseaiceintheArcticduringthelateautumnandearlywinterof2007,theauthorsstudiedthearrivingsolarradiation,reflectedradiationandtransmittedradiationunderverylowsolaraltitude.Throughtheatmosphere,thelightofthearrivingsolarradiationatshortwavelengthwasweakened,withthespectraldistributionofdoublepeakscenteredat490nmand683nm.Themagnitudeofthepeakat683nmevenexceededthatat490nmundertheverylowsolarradiationcondition.Thereflectionwaslowerthanthatinsummertimebecauseofthethinthicknessesoficeandsnow,allowinghigherratioofheattoentertheseaiceandsnow.Whenhigherratioofsolarradiationenteredseaiceinlateautumn,thenewicefreezingwouldbeaffected.Thespectralreflectivityfromsnowsurfacewasalmostaconstant,butthereflectionwithoutsnowde-creasedatlongerwavelengths.Inthetransmissionspectrum,thelightof490nmwasdominant.Itindicatesthattheradiationatlongerwavelengthwasweakenedbyseaice.Therefore,undertheconditionoflowsolaraltitude,theradiationatshorterwavelengthwasweakenedbytheatmospherewhiletheradiationatlongerwavelengthwasweakenedbytheseaice.Thecombinedeffectofat-mosphereandseaicemadethesolarradiationunderseaicemuchweaker.Theabsorptionofseaiceforthelonger-wavelengthradiationallowedtheseaicetogainmoreheattoslowdownthefreezingprocess.
简介:ItisshownthataGaussianlightbeamtransmittingthroughaplanarthindielectricslabintheairundergoesfourdifferenteffects,i.e.lateralGoos–Hnchen-like(GHL)displacement,angulardeflection,widthmodificationandlongitudinalfocalshiftascomparedwiththeresultspredictedbygeometricaloptics.AccordingtotheTaylorexpansionoftheexponentoftransmissioncoefficientwhenexpressedasanexponentialform,thelateralGHLdisplacementandtheangulardeflectionarethefirst-ordereffectsandcanbenegativeorpositive.Thewidthmodificationandthelongitudinalfocalshiftarethesecond-ordereffectsandcanalsobepositiveornegative.Owingtothewaist-widthdependentterm,thenon-geometricaleffectsoftransmittedbeamarenotidenticalwiththenon-speculareffectsofreflectedbeam.Theconditionsforthevalidityofthoseeffectsaresuggestedandnumericalsimulationsarealsogiven.
简介:KaKs_Calculator是计算的一个软件包裹非同义(Ka)并且同义(K)替换通过平均的模型选择和模型评价。因为存在,为这个评价的方法采用他们的特定的变化(替换)考虑不同进化特征的模型,导致多样的估计,KaKs_Calculator在一个最大的可能性框架实现一套候选人模型并且采用Akaike信息标准测量在模型和数据之间的健康,试图包括为精确地在编码蛋白质的序列捕获进化信息需要的同样多特征。另外,为精明的Ka和K的几存在方法也被合并到这个软件。包括源代码,编译可执行文件,和文档,KaKs_Calculator为在http://evolution.genomics.org.cn/software.htm的学术使用是自由地可得到的
简介:一个活动床的、未失真的物理模型(1:40)被用来通过河岸保护移动和丁提尺寸和配置的修正调查不同沉积供应策略到旧来因河,它引起河岸侵蚀。这条训练隧道以前巴塞尔(瑞士)下游地是上面的来因河的主要的床,但是自从宏大运河d'Alsace,一条航行运河,和一个流动控制水坝的构造,它在梳(法国)有人工地低的流动政体。训练工作和随后的隧道切口极大地也减少了沉积运输率并且创造一重重地armoured床。建模的飞行员地点在左河岸上有一个丁提领域。结果证明在这个地点的当前存在的丁提不在创造导致的高银行方面速度存侵蚀是有效的,甚至为比吝啬的年度流动率显著地高的流动率。河岸也比以前想证明了更抵抗,允许安全地要搬迁的河岸保护的长段。在二更高的、更大的岛丁提进一步分开被放比三存在依附的丁提的地方,测试进程的物理模型为丁提域生产了一种新配置。这条创新途径证明了有效,引起为在吝啬的年度流动率下面的流动率的河岸侵蚀,与被观察的一致侵蚀。如此的一种配置不为宏大运河d'Alsace提出危险,这也被发现了,它靠着旧来因河是位于的,通过在高流动事件期间的过多的河岸侵蚀。
简介:THEEFFECTOFOXYGENAPPLIEDTHROUGHDRIDSHIPCONSTANTHEADVESSELTODLALYSATEONDIALYSISHYPOXEMIAZhenguoMi,YushengBao,ChunLiu,XiCao,Jia...
简介:参量的软件努力评价模型通常由仅仅一个单个数学关系式组成。与从异构的工程包含数据的软件仓库的来临,模型的这些类型受不了差的调整和预兆的精确性。减轻这个问题的一个可能的方法是通过根据不同参数历史的工程数据集划分成称为分区的潜水艇数据集获得的一套数学方程的使用。接着,分区被划分成为更精确的模型用作一个工具的簇。在这篇论文,我们用一个公开可得到的仓库通过案例研究描述如此的途径的过程,工具和结果,ISBSG。没有让评价处理使用一个单个评价模型的更多建筑群,结果作为存在单个表示的模型的延期建议这种技术的足够。支持这个过程的一个工具也被介绍。电子增补材料这篇文章(doi:10.1007/s11390-007-9043-5)的联机版本contatins增补材料,它对授权用户可得到。
简介:InteractionbetweentwosphereswithaninterstitialfluidisessentialinDiscreteElementmodelingforsimulatingthebehaviorsof'wet'particulatematerials.InthispapertheinteractionbetweentwosphereswithaninterstitialPower-lawfluidwasapproximatelyresolvedasnormalandtangentialinteractivemodelsrespectively,forwhichthegoverningequationsweresimplifiedonthebasisofReynoldsapproximation.Theseequationswerethensolvedanalyticallytogetherwiththeboundaryconditionstoobtainthepressuredistributionsforeachindividualmodel,andeventuallysolutionsoftheviscoussqueezeforceandthetangentialviscousresistancewereobtained,whichprovideasetofsolutionsforimplementingintoDEMcodeorotherpurposes.