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21.
The concept of crystallization dynamics method evaluating the miscibility of binary blend system including crystalline component
was proposed. Three characteristic rates, nucleation, crystal growth rates (N*, G*) and growth rate of conformation (G
c*) were used to evaluate the miscibility of PVDF/at-PMMA and PVDF/iso-PMMA by the simultaneous DSC-FTIR. N*, G* and G
c* depended remarkably on both temperature and blend fraction (ϕPMMA) for PVDF/at-PMMA system, which indicated the miscible system. PVDF/iso-PMMA showed small ϕPMMA dependency of N*, G* and G
c*, was estimated the immiscible system. The ΔT/T
m0 values, corresponding to Gibbs energy required to attend the constant G* and G
c*, evaluated from G* and G
c* showed the good linear relationships with different slope. The experimental results suggested that the concentration fluctuation
existed in PVDF/iso-PMMA system. 相似文献
22.
J. P. Leroy J. Micheli G. C. Rossi K. Yoshida 《Zeitschrift fur Physik C Particles and Fields》1990,48(4):653-661
In this paper we present a non-trivial check of the consistency of the quantization of a gauge theory with fermions (QCD) in the temporal gauge. We use the approach based on the finite time Feynman propagation kernel, in which the Gauss law is imposed as a constraint on the states by means of a functional integration over all the time independent gauge transformations acting on the boundary values of the fields. We spell out in detail the “Feynman rules” when fermions are present and we compute, as an example, the gauge invariant correlation function $$\begin{gathered} G(t) = \left\langle {\bar \psi (0,t)(\gamma _5 \gamma _0 )\frac{{1 - \gamma _0 }}{2}P} \right. \hfill \\ \left. { \cdot \exp \left( {ig\int\limits_0^t {A_0 (0,t')dt'} } \right)(\gamma _5 \gamma _0 )^ + (0,0)} \right\rangle \hfill \\ \end{gathered} $$ up to orderg 2, obtaining the expected result. 相似文献
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Jaffe DE Straub PB Adams MR Brown CN Charpak G Cooper WE Crittenden JA Finley DA Glass HD Gray R Hemmi Y Hsiung YB Hubbard JR Jonckheere AM Jöstlein H Kaplan DM Lederman LM Luk KB Maki A Mangeot P McCarthy RL Miyake K Plaag RE Rutherfoord JP Sakai Y Santiard JC Sauli F Smith SR Yoshida T Young KK 《Physical review D: Particles and fields》1989,40(9):2777-2795
25.
Nahomi Sakaguchi Keiji Yamada Shuji Matsuo Taku Matsuo Hisanobu Wakita 《Research on Chemical Intermediates》2006,32(2):171-182
Surface modification of TiO2 powders with lanthanide salts (EuCl3 or YbCl3) enhanced photocatalytic decomposition of ATP. In comparison with the unmodified catalyst, a 3-fold increase in the ATP decay
rate was observed with TiO2 powders as prepared in 5 mM EuCl3 (or YbCl3) solution. The reason was ascribed to enrichment of ATP to TiO2 powder with the lanthanide ions. Evidence was obtained by adsorption experiments where ATP concentration was monitored after
dispersing TiO2 powders into the solution. The ATP molecules adsorbed faster to TiO2 powder and strongly stabilized there in the presence of Yb3+ than otherwise. 相似文献
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Summary Chiral stationary phases (CSPs) for liquid chromatography were prepared by the way of an activated carbamate intermediate.
The amino group of aminopropylsilyl silica gel was first activated by carbamylation with disuccinimido carbonate (DSC). The
obtained activated carbamate silica gel (ACsil) proved useful as an intermediate for the preparation of urea-type CSPs. The
reaction of ACsil with (S)- of (R)-1-(α-naphthyl)-ethylamine gave naphthylethylurea type CSPs. These CSPs were also obtained
directly from aminopropylsilyl silica gel by its reaction with optically active (S)- or (R)-succinimido 1-(α-naphthyl)ethyl
carbamate (SINEC). Several phenylthiohydantoin amino acid enantiomers and p-bromophenylcarbamyl amino acid enantiomers were
resolved on the CSPs by elution with aqueous mobile phase. 相似文献
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