简介：对[0,1]上的L—可积函数ф及α>0定义下列B—D—B算子;本文研究了Mna（ф,x）当α>0时,在LP(0,1]（1≤p<+∞）的一致逼近;当α≥1时在LP[O,1]及L1P[0,1]逼近度的量化估计。作者在文[4]中定义了B—D—B算子:其中fnk（X）称为Bézeief基函数文[4]研究的是B—D—B称子在C[0,1]空间中的逼近性质,本文继续[4]的工作,专研究这个算子在LP[0,1]（1≤P<+∞）的逼近性质,证明了Mna（фX）当α>0时在LP[0,1]中为一致逼近,并得到了当α≥1时在LP[0,1]及L1P[0,1]中逼近度的量化估计。

简介：环境友好的L-prolinamide催化丁间醇醛反应被开发了。反应展出了宽广底层概论，并且有好diastereoselectivity的高收益为周期的酉同类被获得。产品隔离的简洁，是的水的用法环境地良性的反应媒介，和用法便宜，容易地可得到并且recyclable催化剂使这个过程有希望为氢氧根酉同类的大规模准备被发展。

简介：本文在L_p（1≤p〈∞）空间上,研究了种群细胞增生中一类具扰动项的一般边界条件下的L-R模型,给出了这类模型相应的迁移方程解的渐近行为等结果.

简介：本文讨论随机环境两性分支过程中以条件均值增长率的上界作为规范化因子的L^1一收敛问题，给出了L^1一收敛的对数判别准则的充要条件．

简介：ＤＭＸ－Ｉ型电子模拟式手弧焊工训练器为国内首创的机电一体化的初级焊工训练器、本文对训练器商品化的前景，训练器的功能的完善等方面的问题进行了讨论．

简介：Halfsandwichirondicarbonylcomplex[η5-C5H3(t-Bu)2]Fe(CO)2Cl(1)reactswith1,2-dilithiumdiselenocarboraneLi2Se2C2B10H10(2)togiveabinuclearironcarboranecomplex[η5-C5H3(t-Bu)2]2Fe2(CO)3*Se2C2B10H10(3).TheX-raydiffractionanalysisofcomplex3revealsthatoneoftheironatomsischiral.

简介：TostudytheintramolecularDiels-Aldercycloadditonof2H-chromen-2-oneasadiene,aseriesofchiralN-allyl-N-benzylamidesthatcontaina2H-chromen-2-onemoietyweredesignedforthesynthesisofbenzo[f]isoindol-l-onesviaanintramolecularDiels-Alderandasubsequentretro-Diels-AldercycloadditionwiththeexpulsionofCO2.Boththeyield（80%-89%）andabsolutestereocontrolofthetandemreactionwerehighwhenanelectron-withdrawinggroupwasattachedtothedienophile.Thedoublebondinthestyrenesubstructureremainedintheproductscouldbefurtherderivatizedbydihydroxylation.

简介：Three-dimensional(3D)flowerlikehierarchicalZn2GeO4andMn2+-dopedZn2GeO4microstructureshavebeenpreparedbyafacilehydrothermalapproach.X-Raydiffraction(XRD),fieldemissionscanningelectronmicro-scopy(FESEM),transmissionelectronmicroscopy(TEM)andphotoluminescence(PL)spectrometrywereemployedtocharacterizethesamples.SuchflowerlikehierarchicalZn2GeO4microstructureswithanaveragediameterof3―4μmwerefoundtobeconstructedbyabundantsinglecrystallinenanorodsofabout90nmindiameter.TheluminescentpropertiesofZn2GeO4:xMnphosphorswithdifferentcontentsofMn2+asanactivatorwereinvestigated.TheMn2+-dopedsamplesshowedgreenluminescencecorrespondingtothed-dtransitionofMn2+undertheirradiationofUVlight.Theredshift(from531nmto538nm)inλemwithincreasingMn2+contentwasobservedintheluminescentspectra,whichshouldbeattributedtoaweakcrystalfieldbecauseofthesubstitutionofZn2+byMn2+atadistortedtetrahedrallatticesite.

简介：设P为素数，利用同余及高次丢番图方程的一些结果证明了不定方程组x-1=3py^2，x^2＋x＋1=3z^2仅有正整数解（p，x，y，z）=（7，22，1，13）。

简介：Asimplemethodisappliedtocalculatingtheisotopeshifts(ISs)on5S1/2→4D3/2,5/2transitionsof87,88Sr+.FirstwehavecalculatedtheISsoflowertransitionsonaseriesofalkali-likesystemssuchasB2+,Ca+andBa+,whichareinagreementwithotherworks.ThentheISson5S1/2→4D3/2,5/2transitionsof87,88Sr+,whichareusefultostudytheSr+opticalfrequencystandard,areevaluated.

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简介：AseriesofTiO2-XSiO2[Xdenotesthemolarfraction(%)ofsilicainthemixedoxides]withdifferentn(Ti)/n(Si)ratioswaspreparedwithammoniawaterasahydrolysiscatalyst.ThephotocatalystspreparedwerecharacterizedbyXRD,thermalanalysis,FTIR,UV-VisandSPS.ThecharacterizationresultsofFTIRandUV-VisspectrashowthatTiatomsweregraduallychangedfromoctahedralcoordinationtotetrahedralcoordinationwiththeadditionofsilica,whichisnotbeneficialforobtainingstrongBrnstedacidityandhigherphotocatalyticactivity.Thephotocatalyticactivityexperiments,whichwereconductedbyusingheptane(orSO2)asthemodelreactant,showedthatTiO2-SiO2containingasuitableamountofsilicacanexhibitmuchhigherphotocatalyticactivitythanpureTiO2.Theenhancedphotocatalyticactivitycanbeattributedtothreefollowingfactors:(1)smallercrystallinesize;(2)higherthermalstability;(3)thenewstrongBrnstedacidity.

简介：ＣａｒｂｏｎｙｌａｔｉｏｎｏｆＡｌｌｙｌＣｈｌｏｒｉｄｅＣａｔａｌｙｚｅｄｂｙＰｄＣｌ２（ＴＰＰＴＳ）２ｉｎＴｗｏ－ｐｈａｓｅＭｅｄｉｕｍＣａｒｂｏｎｙｌａｔｉｏｎｏｆＡｌｌｙｌＣｈｌｏｒｉｄｅＣａｔａｌｙｚｅｄｂｙＰｄＣｌ２（ＴＰＰＴＳ）２ｉｎ...

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简介：ForquadraticnumberfieldsF=Q(√2pl…pt-1)withprimespj≡1mod8,theauthorsstudytheclassnumberandthenormofthefundamentalunitofF.TheresultsgeneralizenicelywhathasbeenfamiliarforthefieldsQ(√2p)withaprimep≡1mod8,includingdensitystatements.Andtheresultsarestatedintermsofthequadraticformx2+32y2andillustratedintermsofgraphs.

简介：设α是正实数,[α0;α1,α2。…]是α的简单连分数;d是非平方整数,d1、d2是适合d1d2=d,1≤d12,gcd（d1,d2）=1的正整数,本文证明了:当且仅当α=（d2/d1）（1/2）时,α=[α0α1,…αn-1,2α0],其中α0>0,αi=αn-1（i=1…,α-1）.

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简介：Takingadvantageofthelargeγ-detectorarrayGammasphereandtherecoilmassseparatorFMA,highspinstatesin117Bawereinvestigatedthroughtherecoil-β-delayedprotondecaytaggingtechniqueviatheheavy-ioninducedfusion-evaporationreaction64Zn(58Ni,2p3n)117Ba,atabeamenergyof305MeV.Promptγraysbelongingto117Bahavebeenidentifiedfurthermore,arotationalbandhasbeenidentifiedforthefirsttimeandpresentedasbandAinFig.1.

简介：Anewmethodforfabricatingorderedporoussiliconisreported.Atwo-dimensionalsilicananospherearrayisusedasatemplatewithahydrofluoricacid-hydrogenperoxidesolutionforetchingthenanospheres.Theinitialdiameteranddistributionoftheholesintheresultingporoussiliconlayeraredeterminedbythesizeanddistributionofthesilicananospheres.Thecorrosiontimecanbeusedtocontrolthedepthsoftheholes.ItisfoundthatthepresenceofaSiO_2layer,formedbytheoxidationoftheroughinternalsurfaceofthehole,istheprimaryreasonallowingthecorrosiontoproceed.Ultravioletreflectionandthermalconductivitymeasurementsshowthatthediameteranddistributionoftheholeshaveagreatinfluenceonpropertiesoftheporoussilicon.