简介：Basedontherainbow-ladderapproximationoftheDyson-Schwingerequationsandtheassumptionoftheanalytieityofthefermion-bosonvertexintheneighborhoodofzerochemicalpotential(μ=0)andneglectingtheμ-dependenceofthedressedgluonpropagator,weapplythemethodin[Phys.Rev.C71(2005)015205]ofstudyingthedressedquarkpropagatoratfinitechemicalpotentialtoprovethatthegeneralfermion-bosonvertexatfiniteμcanalsobeobtainedfromtheoneatμ=0byasimpleshiftofvariables.Usingthisresultweextendtheresultsof[Phys.Lett.B420(1998)267]tothesituationoffiniteehemicalpotentialandshowthatundertheapproximationswehavetaken,theGe11-MannOakesRennerrelationalsoholdsatfinitechemicalpotential.

简介：Weintroducethepolarizedvalondistributionstodescribethespindependenceofpartondistributions.Thepolarizedvalondistributionsintheprotonandpolarizedpartondistributionsinsidethevaloncanhelptoobtainpolarizedpartondistributioninaproton.Inordertobeabletoobtainthespincontributionofseaquarks,weneedtoimprovethevalonmodelWeemploytheBernsteinpolynomialaveragestoobtaintheunknownparameterswhichexistinourcalculations.Ourresultsforthepolarizedprotonstructurefunction,xg1p,areingoodagreementwiththeexperimentaldataforsomevaluesofQ2.

简介：Background:Oneofthemostimportantdriversofforestbiodiversityisconspecificnegativedensitydependence(CNDD),areductioninperformancewhenconspecificdensitiesarehigh.WhilethemajorityofCNDDresearchhasfocusedontropicalforests,evidenceismountingthatCNDDmayalsoplayanimportantroleintemperateforests.Tofurtherexplorethepotentialreachofthisphenomenon,weinvestigatedCNDDinAmericanbeech(Fagusgrandifolia)inamaturemid-Atlanticforest.Methods:Weusedbivariatepointpatternanalysestoexaminespatialrelationshipsbetweenlargebeechtreesandconspecificsaplings,andwealsocontrastedthesepatternswithcomparablepatternsforheterospecifics.Inaddition,toaddressthepossibilityofdispersallimitationandtheassociatedeffectsonspatialpatterns,weanalyzedseedlingdensityasafunctionofadultconspecificabundance.Results:Wefoundthatbeechsaplingsweremorerepeledfromlargeconspecificsthanlargeheterospecifics,despitethefactthatbeechseedlingdensitywaspositivelycorrelatedwithbeechbasalarea.However,saplingsofothercanopytreespecieswerealsorepeledfromadultbeechtrees,suggestingageneralsuppressiveeffect.Nonetheless,thediscrepancybetweenbeechseedlingandsaplingdensitiesbeneathadultconspecificssuggeststhatbeechseedlingsurvivalrateswerereducedinvicinityofconspecificadults.Conclusions:Regardlessoftheextenttowhichbeechinhibitsheterospecifictrees,anegativeeffectonconspecificrecruitsmaybecriticalforbiodiversitymaintenance.Withoutthisconspecificsuppression,adenselayerofshade-tolerantbeechsaplingscouldformbeneathadultbeechtrees.Ifthisweretooccur,beechwouldhaveasubstantialhead-startfolowingcanopydisturbance,andthislate-successionalspeciescouldpotentialydominateastandinperpetuity,throughrepeateddisturbancecycles.

简介：Inlargetokamakdeviceandreactordesigns,therelationshipbetweenthetoroidalcurrentandtheedgesafetyfactorisveryimportantbecausethiswilldeterminetheeventualdeviceorreactorsizeaccordingtoMHDstabilityrequirements.Inmanypreliminary

简介：空间关联系数是为对浅水里的健全繁殖的描述的最重要的参数之一。纵的关联长度的频率依赖仍然是一个开的话题。我们在一个浅水实验观察到以波长的单位的纵的关联长度随频率的增加增加。这现象没在出版报纸被看见。理论分析和数字模拟显示底部变细的非线性的频率关系是这现象的主要原因。

简介：ＤｅｐｅｎｄｅｎｃｅｏｆΓｏｎＲｅａｃｔｉｏｎＦｒａｇｍｅｎｔｓｉｎＤｉｓｓｉｐａｔｉｖｅＨｅａｖｙｉｏｎＣｏｌｌｉｓｉｏｎ￥ＷａｎｇＱｉ；ＬｕＪｕｎ；ＸｕＨｕｓｈａｎ；ＬｉＳｏｎｇｌｉｎ；ＺｌｌｕＹｏｎｇｔａｉ；ＹｉｎＸｕ；Ｆａ...

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简介：让{Xt≥1}一个动人的平均过程被在哪儿定义{akk≥0}是实数的一个序列并且{t，∞

简介：ＳｔｒｏｎｇＳｉｇｎａｔｕｒｅＤｅｐｅｎｄｅｎｃｅｏｆＹｒａｓｔＬｅｖｅｌｓｉｎ１６２Ｌｕ￥ＺｈａｎｇＹｕｈｕ；ＺｈｏｕＸｉａｏｈｏｎｇ；ＺｈａｏＱｉｎｇｚｈｏｎｇ；ＳｕｎＸｉａｎｇｆｕ；ＬｅｉＸｉａｎｇｇｕｏ；ＧｕｏＹｉｎｇｘｉａ?..

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简介：AtheoreticalcalculationforthetemperaturedependenceoftheexcitonictransitioninZnSe/ZnCdSequantumwellsisperformed.Theexcitonbindingenergyiscalculatedwithavariationaltechniquebyconsideringthetemperature-dependenceparameters.Ourresultsshowthattheexcitonbindingenergyreduceslinearlywithtemperatureincreasing.Wefindthatthestrainduetolatticemismatchanddifferentialthermalexpansiondecreaseswiththetemperatureincreasing.

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简介：ThediamondfilmshavebeendepositedbythehotfilamentCVDmethodonmolybdenumsubstratesfromthemixturereactantgasofacetoneandhy-drogen.Thesurfacemorphologiesoftheobtaineddiamondfilmsundervariousde-positionconditionshavebeenobservedbyscanningelectronmicroscope(SEM).Theexperimentalresultsstronglyindicatethatthesurfacemorphologiesofthere-sultingfilmshavecloselyrelatedtothedepositionconditions,i.e.,reactionpres-sure.Formolybdenumsubstrates,underthelowerreactionpressurethesurfacemorphologiesofthegrainscomprisingtheresultingfilmsmainlydisplaythesmallsinglecrystalcubo-octahedronanddoublesmallcrystalcubo-octahedron;underthehigherreactionpressure,thesurfacemorphologiesmainlydisplaythelargecauliflower-like.TheseresultsshowthattherearevariouscrystalhabitsforCVDdiamondundervariousdepositionconditions.

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简介：Foralongtime,relationsbetweentheEuropeanUnionandAfricaarenotonanequalfooting.Asearlyashalfacenturyago,theEuropeanCommunity,predecessoroftheEU,drovetheformercoloniesofsomememberstatesintoaframeworkof'special

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简介：降水和联系的云水疗院流星有大时间、空间的可变性，它使预报的精确量的降水困难。因此，精确降水的依赖和时间、空间的规模上的联系的云模拟成为一个重要问题。我们报导由把控制实验与实验作比较在这个问题上解决当模特儿的分析的云由起始的温度，水蒸汽，和云条件使不安。仅当不安实验和控制实验之间的root-mean-squared差别比标准差小，模拟被认为精确。分析可以建议精确降水和云模拟不能同时在两好时间、空间的规模上被获得，它限制预报的量的降水。水蒸汽集中的精确模拟能在每日的时间规模上导致精确降水和云模拟，但是它不能对降水和云模拟有益在上时时，时间由于云过程的优势可伸缩。

简介：盆区域是平均数和山峰流速及流水量上的主要控制，但是关系与地区性的气象学的条件变化。富有的历史的数据集合为美国的大多数区域允许这些关系的推理，揭示期望并且意外关联。在木头木头阴谋上，为大多数盆意味着流动与>75cm/y降雨有单位斜坡，与接近的y拦截吝啬的年度流量。更低的斜坡描绘流量在高地志的举起是最大的区域，否则为灌溉的重要退却在在哪儿发生，降低举起。山峰流动也与盆区域强烈相关，但是为大多数区域的回归有从0.4～0.9的斜坡，和与增加增加的y拦截泛滥复发间隔。为山峰流动的这些木头木头阴谋上的斜坡在有低阳光和低土壤水分蒸发蒸腾损失总量的凉爽的区域是最高的，并且最低在阳光是丰富的的地方，土壤水分蒸发蒸腾损失总量高、小对流暴风雨房间是普通的。地势的效果小、不一致。小分水岭的山峰流动与他们的吝啬的流动相比是巨大的，通常大几千倍，特别地在为山峰流动的斜坡是低的美国midcontinent。