[](1986-),,,,。20097Jul.2009244JournalofXianyangNormalUniversityVol.24No.4,[1],[2],,。,,。MATLAB[3],。,,、。,,MATLAB[4,5]。MATLAB[6],、,。坠u坠t=a2坠2u坠x2,,,,、;,。,、、;,[7](FDM),。FDM,。,:坠u坠t=a2坠2u坠x2,0<l,t>0u|x=0=0,u|x=l=0,t>0u|x=0=sinπxl!,0<x<#%%$%%&l,,。Taylor,,。1,;;,,,,。[8,9]。:(1);(2);(3);(4)。MATLAB(,710055):,。,MATLAB。,MATLAB,。:;;MATLAB:O552:A:1672-2914(2009)04-0027-03·28·242,(x-t),△x=l/M,△t=T/N,,,,。u(x,t)t[10]:坠u坠t≈unj-un-1j△t,t[10]:坠2u坠x2≈unj+1-2unj+unj-1(△x)2,。:unj-un-1j△t=a2unj+1-2unj+unj-1(△x)2。:r=a2·△t(△x)2,(1+2r)unj-r·unj+1-r·unj-1=un-1j。:1+2r-r00…0-r1+2r-r0…000-r1+2r-r00…00-r1+2++++++++++++++r(M-1)×(M-1)un1un2unM-2unM-1++++++++++++++++++=un-11+r·un0un-12un-1M-2un-1M-1+r·unM++++++++++++++++++3MATLAB%clear;clc;formatshortea=input('a:');l=input('l:');M=input('[0,l]M:');ot=input('ot:');n=input('n:');ox=l/M;x0=zeros(M+1,1);forii=1:Mx0(ii+1)=ii*ox;endu=sin(pi*x0/l);%t=0u(x,t)r=a^2*ot/(ox)^2;forii=1:n%B=zeros(M-1,1);%A=zeros(M-2,1);%C=zeros(M-2,1);%S=zeros(M-1,1);%forii=1:M-2B(ii)=1+2*r;A(ii)=-r;C(ii)=-r;S(ii)=u(ii+1,1);endB(M-1)=1+2*r;S(M-1)=u(M,1);u(1,2)=0;u(M+1,2)=0;S(1,1)=S(1,1)+r*u(1,2);S(M-1,1)=S(M-1,1)+r*u(M+1,2);%S(1)=S(1)/B(1);T=B(1);k=2;whilek~=MB(k-1)=C(k-1)/T;T=B(k)-A(k-1)*B(k-1);S(k)=(S(k)-A(k-1)*S(k-1))/T;k=k+1;endk=1;whilek~=M-1S(M-1-k)=S(M-1-k)-B(M-1-k)*S(M-k);k=k+1;endu(2:M,2)=S;%uu(:,1)=u(:,2);%end%,uforx=0:Mu(x+1,2)=exp(-(pi*a/l)^2*n*ot)*sin(pi*x*ox/l);tTn+1nn-10j-1jj+1lx(j-1,n)(j-1,n)(j,n)(j+1,n)(j,n-1)→←△x△t↓↑1…………………誗誗誗誗4:MATLAB·29·end%ez=zeros(M-1,1);forii=2:Mez(ii-1)=abs(u(ii,1)-u(ii,2))/u(ii,2);endE=max(ez);fprintf(':\n');disp(u);fprintf(':');disp([num2str(E*100)'%']);%plot(x0,u(:,1),'r:',x0,u(:,2),'b-');legend('','')xlabel('x'),ylabel('u(x,t)')title('')。4:a:1l:1[0,l]M:8ot:0.001n:901。:1.5723%。ξj||ξj||燮C||ξ0||,(j叟1)(ξ0),,1,,2。5MATLAB,,,MATLAB,。:[1],,.[J].,2005,19(4):76-80.[2],,.[J].(),2007,20(3):12-14.[3]StephenJ.Chapman.MATLAB[M].,,.:,2008.[4].MATLAB[J].,2006,20(4):12-13.[5],.MATLAB[J].(),2003,22(4):21-27.[6].[J].,2008,24(2):31-36.[7].[J].(),2004,34(3):16-18.[8],.MATLAB[J].,2005,18(4):61-64.[9],.MATLAB[J].,2008,21(3):1-2.[10].[M].:,1979.1001.5990e-0011.5990e-0012.9546e-0012.9088e-0013.8603e-0013.8006e-0014.1784e-0014.1137e-0013.8603e-0013.8006e-0012.9546e-0012.9088e-0011.5990e-0011.5742e-00105.0378e-017(36)HeatConductionEquationFiniteDifferenceMethodtoAchievetheMATLABSHICe(SchoolofScience,Xi'anUniversityofArchitectureandTechnology,Xi'an,Shaanxi710055,China)Abstract:Forboundedhomogeneousheatconductionequationofthemixedproblem,separationofvariablesmethodusedisoftenverycomplex.Inordertobetterunderstandtheheatconductionequation,itisusefultoapplytheMATLABsoftwareequationbyimagesexpression.Thoughwhichtransformsthroughtheregion,whichispro-grammingusingMATLABheatconductionequationofacertainregionofthefinitedifferencemethod,andnumer-icalmethoddemonstratesthefeasibilityandstability.Keywords:heatconductionequation;finitedifference;MATLAB·36·24tionoforganicpollutantsonnitrogenandfluorideco-dopedTiO2photocatalyst[J].JournalofEnvironmentalSciences,2005,17(1):76-80.[9]OhnoT,AkiyoshiM.PreparationofS-dopedTiO2photocata-lystsandtheirphotocatalyticactivitiesundervisiblelight[J].AppliedCatalysisA:2004,265:115-121.[10]UmebayashiT,YamakiT.Analysisofelectronicstructuresof3dtransitionmetal-dopedTiO2basedonbandcalculations[J].JournalofPhysicsandChemistryofSolids,2002,63:1909-1920.[11]BalachandranU,ErorNG.Laser-inducedvapourphasesyn-thesisoftitaniumdioxide[J].JournalofSolidStateChem-istry,1982,42:276-282.[12]MelendresCA.RamanspectroscopyofnanophaseTiO2Source[J].MaterialsResearchBulletin,1989,4(5):1246-1250.[13]ParkerJC,SiegelRW.RamanmicroprobestudyofnanophaseTiO2andoxidation-inducedspectralchanges[J].MaterialsResearchBulletin,1990,5(6):1246-1249.[14]AraiT,YanagidaM,KonishiY.Effficientcompleteoxida-tionofacetaldehydeintoCO2overCuBi2O4/WO3compositephotocatalystundervisibleandUVligntirradiation[J].Phys-icalChemistry,2007,111(21):7574-7577.PreparationofTiO2PhotocatalystCouplingDopedwithSandNElementsYUZhan-jiang,WANGXiao-fang(SchoolofChemistryandChemicalEngineering,XianyangNormalUniversity,Xianyang,Shaanxi712000,China)Abstract:UsingtetrabutyltitanateasTisource,glacialaceticacidasahydrolyzedinhibitorandDL-methion-ineasasmallmoleculedopant,aTiO2photocatalystcouplingdopedwithSandNnonmetallicelementswaspre-paredviaSol-Gelmethod.XPSanalysisshowsthatN2-incorporatesintotheTiO2crystallatticeandreplacedpartlyO2-,andthattheS4+andS2-alsoincorporateintotheTiO2crystallatticeandsubstitutepartialTi4+andO2-respec-tively.HencetheformationofSandNcoupling-dopingonTiO2getsachieved.XRDdiffractionindicatestheSandNcouplingdopedTiO2photocatalystsallexistinthephaseofanatase,whichdemonstratethatSandNcou-pling-dopingfeaturesstrongereffectonrestrainingtheTiO2crystalphasetransformationfromanatasetorutile.OpticalpropertyanalysispresentsthattheSandNcoupling-dopinghaseffectnotonlyonextendingabsorptionedgeofphotocatalysttovisiblelightregionbutonkeepingtheultravioletlightabsorptionnearlyunchanged.Keywords:photocatalyst;coupling-doping;titaniumdioxide;Sol-Ge