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51.
The purpose of this paper is to survey the theory of regular Fréchet-Lie groups developed in [1–10]. Such groups appear and are useful in symplectic geometry and the theory of primitive infinite groups of Lie and Cartan [11]. From the group theoretical standpoint, general relativistic mechanics is a more closed system than Newtonian mechanics. Quantized objects of these classical groups are closely related to the group of Fourier integral operators [12]. These can also be managed as regular Fréchet-Lie groups. However, there are many Fréchet-Lie algebras which are not the Lie algebras of regular Fréchet-Lie groups [13]. Thus, the enlargeability of the Poisson algebra is discussed in detail in this paper. Enlargeability is relevant to the global hypoellipticity [14, 15] of second-order differential operators.  相似文献   
52.
Irradiation of chloro- and bromoalkanes in solid cis-decalin-d18 results in the selective formation (as major paramagnetic species) of alkyl radicals that are specific or the haloalkane solute, in addition to matrix radicals. The method offers a convenient and universal technique for generating, specific alkyl radicals and for examining their powder ESR spectrum. Examples of the generation of chain-end, penultimate and interior alkyl radicals are given. Computer calculations, in which spectra of penultimate and interior radicals are added, clearly demonstrate that quite extensive amounts of interior radicals can be present in a radical mixture, without considerably affecting the composite spectrum.  相似文献   
53.
Reactions of pertechnetate ion with thiourea (tu) in a hydrochloric acid solution have been investigated by spectrophotometry. Two consecutive reactions were observed for the formation of a technetium-thiourea complex. The intermediate is considered to be a Tc(V)-tu complex ([TcO(tu)4]3+). The observed reaction rates of these two reactions were found to be second order with respect to the concentration of thiourea. The rate-determining step in the 1st step was concluded tobe the reduction of Tc(VII) to Tc(V) and that in the 2nd step to be the reduction of Tc(V) to Tc(III).  相似文献   
54.
55.
The distribution of proteins in the cerebral cortex of a seizure-sensitive (SS) strain of gerbil and its seizure-resistant (SR) counterpart was profiled using two-dimensional gel electrophoresis. A series of proteins of similar molecular weight (around 83 kDa) showed small but consistent differences in their isoelectric point (pI) with indistinguishable profiles of distribution between the two strains. Amino acid sequences of peptides produced by limited proteolysis of each protein in the spots from the strains were identical or highly homologous to those of mitofilin, a mitochondrial inner membrane protein (IMMT) in humans. Analysis of cDNA sequences revealed the proteins of these spots to be gerbil mitofilin-like proteins (gIMMT), with a few base substitutions between SS and SR strains, in particular within a region near a putative transmembrane domain that is highly conserved in humans and gerbils. The amino acid at the site was acidic, Glu in humans and Asp in the strain SR of gerbil and a neutral, Asn in strain SS. In addition to these base substitutions, production of multiple species of mRNA for gIMMT by alternative splicing was observed.  相似文献   
56.
Summary The oxidation state of the superconductor Bi-Ca-Sr-Cu-O was determined by two procedures. One was ferrous-chromate titration after dissolution of the sample in manganous nitrate solution. The other was the titration after dissolution in ferrous ion solution. The former procedure gives the concentration of a state like pentavalent bismuth and the latter gives the sum of concentrations of a state like pentavalent bismuth and a state like trivalent copper or peroxide. The result of the titration shows that the superconductor oxide has the state like pentavalent bismuth but not like that of trivalent copper. This is a striking contrast to YBa2Cu3O7–y having a high concentration of the latter state. Although the result was compared with X-ray photoelectron spectra, a clear relationship between them was not obtained.
Bestimmung der Oxidationsstufen von Bismut und Kupfer im Supraleiter Bi-Ca-Sr-Cu-O durch Redoxtitration
  相似文献   
57.
Reaction mechanism of base hydrolysis of halobis/8-quinolinolato/oxotechnetium (V) /TcOX (ox)2 X=Cl and Br/ was investigated by means of solvent extraction and spectrophotometric methods. Furthermore, distribution coefficients of tris/acetylacetonato/technetium/III/, dichlorobis/8-quinolinolato/technetium/IV/ and TcOX/ox/2 between chloroform and aqueous solutions were determined. In an alkaline solution, TcOX/ox/2 decomposed to pertechnetate as a final product. On the basis of the established base hydrolysis, the respective rate constants were determined.  相似文献   
58.
The electrochemical fluorination of chlorine-containing alkylamines has been studied. It was found that, in general, the carbon-chlorine bond in the alkylamines is retained during electrochemical fluorination is anhydrous hydrogen fluoride, yielding chlorine-containing polyfluoroalkylamines. Perfluoroalkylamines and fluorocarbons were also produced.By the use of this method, several new chloropolyfluoroamines such as (CF3)2NCF2CClF2, (C2F5)2NCF2CClF2, (CF3)(C2F5)NCF2CClF2, (CClF2CF2)2NCF3, (CClF2CF2)2NC2F5, (C2F5)(CClF2CF2)NF, (CClF2CF2)2NF, (CF3)2NCF2CF2CClF2, CF2(CF2)3NCF2CClF2, and CF2CF2OC2F4NCF2CClF2 have been isolated and characterized.  相似文献   
59.
N-Alkylation significantly changes the electronic and optical properties, as well as the reactivity of nitrogen-containing π-conjugated molecules. In this study, it is found that treating 5,15-diazaporphyrins with methyl triflate selectively affords the corresponding N-methyl-5,15-diazaporphyrinium cations in good yield. N-Methylation substantially alters the electronic properties and reactivity of diazaporphyrins. The electron-accepting properties of the N-methyl-5,15-diazaporphyrinium cations are enhanced due to their lowered LUMO level. Stabilization of the LUMO energy enables regio- and stereoselective Diels–Alder reactions of the cationic diazaporphyrin with cyclopentadiene. N-Methylation also enhances the acidity of the inner NH protons, and thus, allows facile deprotonation to provide nitrogen-substituted isoporphyrin analogues with only one NH group in the central cavity.  相似文献   
60.
N-Carbobenzoxy-α-alkoxyglycine esters were synthesized by H2SO4-catalyzed O-alkylation of N-carbobenzoxy-α-hydroxyglycine and also by base treatment of N-carbobenzoxy-N-chloroglycine methyl ester in the corresponding alcohol. Saponification of the protected α-alkoxyglycines gave free acids which can be used for the synthesis of α-alkoxyglycine residue-containing peptides.  相似文献   
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