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1.
Ernest Shult 《Journal of Geometry》1997,59(1-2):152-172
This paper continues a program to show that for most of the standard Lie incidence geometries, all geometric hyperplanes arise from a necessarily absolutely universal embedding, by addingE
7,1 to the list. It follows from [5, 12] that any projective embedding of this point line geometry is a homomorphic image of the one afforded by the 56-dimensional module for the groupE
7(K).This work was supported by a grant from the National Science Foundation. 相似文献
2.
3.
K. C. Nicolaou Dionisios Vourloumis Tianhu Li Joaquin Pastor Nicolas Winssinger Yun He Sacha Ninkovic Francisco Sarabia Hans Vallberg Frank Roschangar N. Paul King M. Ray V. Finlay Pareskevi Giannakakou Pascal Verdier-Pinard Ernest Hamel 《Angewandte Chemie (International ed. in English)》1997,36(19):2097-2103
4.
Polyazido high-nitrogen compounds: hydrazo- and azo-1,3,5-triazine 总被引:13,自引:0,他引:13
Huynh MH Hiskey MA Hartline EL Montoya DP Gilardi R 《Angewandte Chemie (International ed. in English)》2004,43(37):4924-4928
5.
Martine Tessier Ernest Marechal 《Journal of polymer science. Part A, Polymer chemistry》1989,27(2):539-553
Several di-, tri- or multiblock poly(isobutylene-b-amide-11)s are prepared by reaction of α-mono or α,ω-dianhydride oligoisobutylenes with α-mono or α,ω-diamino oligoamides, in o-dichorobenzene at 140°C. They are characterized mainly by 1H- and 13C-NMR spectroscopy and GPC, using the trifluoroacetylation technique. Their thermal differential chromatograms are reported and analyzed. 相似文献
6.
Christopher Murray Ernest R. Davidson 《International journal of quantum chemistry》1992,43(6):755-768
Different forms of perturbation theory for the calculation of correlation energy in both closed-and open-shell systems are discussed. For closed-shell systems, Epstein–Nesbet perturbation theory is compared with Møller–Plesset (MP ) perturbation theory based on canonical Hartree–Fock orbitals and with MP theory based on internally consistent SCF orbitals. The traditional MP theory gives superior results despite its use of an inferior zeroth-order Hamiltonian. This behavior is rationalized in terms of the larger denominators present in the traditional MP theory. These conclusions are used to support the restricted open-shell perturbation methods proposed recently by Murray and Davidson, and these new methods are compared with spin-restricted Epstein–Nesbet theory and the unrestricted MP (UMP ) approach. © 1992 John Wiley & Sons, Inc. 相似文献
7.
4-Isothiazolin-3-one 1-oxides and 1,1-dioxides react with a variety of cyclic and acyclic dienes to afford cycloaddition products. 相似文献
8.
Ernest Wenkert Edward W. Hagaman Nicole Kunesch Nai-yi Wang Bla Zsadon 《Helvetica chimica acta》1976,59(8):2711-2723
The 13C shifts of 16α- and 16β-substituted derivatives of quebrachamine, 14,15-dehydroquebrachamine, cleavamine, 15,20α-dihydrocleavamine and 15,20β-dihydrocleavamine are determined and correlated with possible conformations of these tetracycles. The method of analysis of the C(16) configuration of these compounds, which emanated from this study, is used for the determination of the configuration of the site of coupling of vindoline and cleavamine β-chloroindolenine. 相似文献
9.
Amperometric urea biosensor based on urease and electropolymerized toluidine blue dye as a pH-sensitive redox probe 总被引:4,自引:0,他引:4
Vostiar I Tkac J Sturdik E Gemeiner P 《Bioelectrochemistry (Amsterdam, Netherlands)》2002,56(1-2):113-115
The electropolymerized toluidine blue film deposited on the glassy carbon electrode show amperometrically detectable pH sensitivity. This feature of polytoluidine blue (PTOB) film was used for a construction of an amperometric urea biosensor. We have observed a linear shift of the formal redox potential with increasing pH value between 4 and 8 giving the slope of 81 mV(Delta) pH(-1). Polytoluidine blue film has had a significantly increased stability and higher electrochemical activity compared to the adsorbed monomeric dye. The polytoluidine blue urea biosensor has been operating at a working potential of -200 mV vs. SCE. The sensitivity of the biosensor was 980 nA mM(-1) cm(-2). The biosensor showed linearity in concentration range up to 0.8 mM with the detection limit of 0.02 mM (S/N=3). 相似文献
10.
Diane C. Rawlings Martin Gouterman Ernest R. Davidson David Feller 《International journal of quantum chemistry》1985,28(6):823-842
Ab initio CI calculations are reported on the lowest doublet, quartet, and sextet states of [FeIII(P)(NH3)2]+. The low-spin ground state is calculated as (dxy2 (dπ)3 with dxy(dπ)4 higher by 0.15 eV. The near-ir bands at ~1 eV observed in low-spin ferriheme proteins are attributed to (π → dπ) transitions. The lowest high-spin state is 6A1g, and the near-ir transitions of the high-spin ferriheme proteins observed at ~1.2 eV are attributed to higher 6[tripsextet] excited states [i.e., ring triplet, metal sextet]. The 30-ps “triplet” transient populated with low quantum yield observed in laser-flash studies on FeIII(TPP)CI [TPP = tetrapbenylporphyrin] may be an 1[tripsextet] state. 相似文献