/.Ps.Chem.B2001.105.4657-4662 4657 Determination of Pore Size in Mesoporous Thin Films from the Annihilation Lifetime of Positronium T.L.Dull,W.E.Frieze,and D.W.Gidley* Department of Physics,University of Michigan,Ann Arbor.Michigan 48109 J.N.Sun and A.F.Yee Department of Materials Science and Engineering.University of Michigan,Ann Arbor,Michigan 48109 Received:November 14.2000:In Final Form:February 15.2001 Mat.Res.Soc.Symp.Proc.Vol.726 2002 Materials Research Society Characterizing Porosity in Nanoporous Thin Films Using Positronium Annihilation Lifetime Spectroscopy J.N.Sun,D.W.Gidley,Y.F.Hu,W.E.Frieze and S.Yang' Department of Physics,University of Michigan.Ann Arbor,MI 48109 Bell Laboratories,Lucent Technologies,600 Mountain Ave.,Murray Hill,NJ 07974 PDF文件使用"pdfFactory”试用版本创建w.fineprint.cn
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非 auirple Manipnlal L☑ Ileddla Aloea 1.:，-4)k T89? Aenalern-o tnal T以' I'1-川1岁 1 2.1川，141 ample l'rep i.ci5 1》.4ugr 12r11"3 staton Na B Hource ond Moderator 一1 Gamma Detector Positron CEMA Beam Beam Sample Schematic of a Depth-Profiled Positron Spectrometer at the University of Michigan. PDF文件使用"pdfFactory”试用版本创建l.fineprint.cn
• Schematic of a Depth-Profiled Positron Spectrometer at the University of Michigan. PDF 文件使用 "pdfFactory" 试用版本创建 Ìwww.fineprint.cn ÿÌ
However,there is no well-defined quantum mechanical model that works for both sub-nanometer voids and big mesopores.We have developed rectangular extension of the existing Tao-Eldrup model,to fully extend the quantum mechanical model to the classical,large-pore limit. 160 OK(Ground State) 140 120 100 Tao-Eldrup Classical Regime Regime 80 60 298K 020 600K 900K 0 10 100 l(nm） PDF文件使用"pdfFactory”试用版本创建l.fineprint.cn
• However, there is no well-defined quantum mechanical model that works for both sub-nanometer voids and big mesopores. We have developed rectangular extension of the existing Tao-Eldrup model, to fully extend the quantum mechanical model to the classical, large-pore limit. PDF 文件使用 "pdfFactory" 试用版本创建 Ìwww.fineprint.cn ÿÌ
Rectangular Tao-Eldrup model (RTE) fits Tao-Eldrup model in the sub-nanometer pore regime; o fits precision measurement data in the classical pore regime O fits experimental data in the intermediate regime, o valid for all temperatures PDF文件使用"pdfFactory”试用版本创建ww.fineprint.cn
Rectangular Tao-Eldrup model (RTE) lfits Tao-Eldrup model in the sub-nanometer pore regime; lfits precision measurement data in the classical pore regime ; lfits experimental data in the intermediate regime; lvalid for all temperatures . PDF 文件使用 "pdfFactory" 试用版本创建 ÿwww.fineprint.cn
160 140 120 100 80 60 ----Tao-Eldup 40 一RTE 4444404 Tokyo Fit 20 Tokyo Data (wio Moscow) 0 Moscew Data ◆ GMR Data 0 10 100 I(nm) A comparison of the TE (ground state only)model,the Tokyo fit, and the RTE model with experimental data.The outlying Moscow point indicated by the arrow,which is anomalously low because of Ps lifetime quenching in air,was not used in the Tokyo fit. Unfortunately,the rest of the Moscow data were also collected in air and require correction. PDF文件使用"pdfFactory'” 试用版本创建w.fineprint..cn
A comparison of the TE (ground state only) model, the Tokyo fit, and the RTE model with experimental data. The outlying Moscow point indicated by the arrow, which is anomalously low because of Ps lifetime quenching in air, was not used in the Tokyo fit. Unfortunately, the rest of the Moscow data were also collected in air and require correction. PDF 文件使用 "pdfFactory" 试用版本创建 Ìwww.fineprint.cn Ì