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111.
Dr. Lisa Hefendehl-Hebeker 《Monatshefte für Mathematik》1980,90(3):219-228
Motivated by an investigation ofKuz'min [2], in this note we introduce a topology on the set
of nonassociative algebras of a fixed dimensionr< over a local fieldF. We obtain a space, which is notT
1. If the trivial algebra
is removed, the remaining subspace is quasicompact. The space is homeomoprhic to the group of square classes ofF
*; forr3 the space is notT
1. The set of division algebras is open in. 相似文献
112.
Dr. Frank Piefke 《Monatshefte für Mathematik》1980,89(1):45-56
We continue our investigations started in a paper with the same title. The -length of a curve defined in this paper can be written as an integral along the curve. Furthermore, we determine necessary and sufficient conditions for the existence of a measure of orientated lines which generates a given non-symmetric pseudo-metric.
Herrn Prof. Dr. H.-J. Kanold zum 65. Geburtstag gewidmet 相似文献
Herrn Prof. Dr. H.-J. Kanold zum 65. Geburtstag gewidmet 相似文献
113.
Dr. Moritz Armsen 《manuscripta mathematica》1977,20(3):245-253
The classical Gauss-Bonnet formula has the form I(gij)=2, where I(gij) represents a sum of three terms each of which depends on the metric tensor gij. It is shown that the first variation I of I(gij) with respect to the metric gij vanishes and that for the Euclidean metric ij we have I(ij)=2. From this the formula I(gij)=2 follows. In the process, explicit expressions are obtained for the first variation of each of the three terms which comprise I(gij). Furthermore, a general expression for the first variation of a multiple integral whose integrand is a scalar density depending on the metric tensor gij and its derivatives up to the second order is obtained with the aid of results of Rund [1]. 相似文献
114.
The Mitsunobu reaction is a widely used and versatile method for the dehydrative oxidation–reduction condensation of an acid/pronucleophile usually with a primary or secondary alcohol that requires the combination of a reducing phosphine reagent together with an oxidizing azo reagent. The utility of this reaction stems from the fact that it is generally highly stereoselective and occurs with inversion of the stereochemical configuration of the alcohol starting material. Furthermore, as carboxylic acids, phenols, imides, sulfonamides, and other compounds can be used as the acid/pronucleophile, this reaction is useful for the preparation of a wide variety of functional groups. This Focus Review of the Mitsunobu reaction summarizes its origins, the current understanding of its mechanism, and recent improvements and applications. 相似文献
115.
We report the gas-phase preparation of negatively charged glycine as well as the Gly(H(2)O)(1,2) (-) complexes by entrainment of the neutral precursor into an ionized supersonic expansion tuned to optimize the (H(2)O)(n) (-)Ar(m) clusters. The photoelectron spectrum of Gly(-) displays the signature of a dipole-bound species, with sufficient vibrational fine structure to characterize the core neutral as a higher energy, non-zwitterionic isomer of the amino acid. 相似文献
116.
117.
Dr. J. Kegel 《Analytical and bioanalytical chemistry》1972,276(1):45-50
The direct determination of CO2 is often faulty because of certain contents of the natural water. Due to this reason a specific method was worked out. The water to be analysed and distilled water are placed side by side in a gas-tight vessel with an atmosphere free of CO2, whereby mixing is avoided but gas-exchange is possible. After adjustment to the gas-equilibration the CO2 content of the distilled water is determined e.g. by titration, measuring of conductivity or other methods, from where the CO2 content in the natural water is calculated. 相似文献
118.
Qiang Xu Prof. Dr. Nobuko Tsumori Prof. Dr. Ling Jiang Masanobu Kondo Ryuichi Arakawa Prof. Dr. 《化学:亚洲杂志》2007,2(5):599-608
Carbonyldinitrosyltris(fluorosulfato)tungstate(II) and ‐molybdate‐(II) anions, [fac‐M(CO)(NO)2(SO3F)3]? (M=W, Mo), which are novel weakly coordinating anions that contain a metal carbonyl/nitrosyl moiety, have been generated in fluorosulfonic acid and completely characterized by multinuclear NMR, IR, and Raman spectroscopy as well as ESI mass spectrometry. ESI MS measurements performed for the first time on a superacidic solution system unambiguously reveal the formation of the monoanionic, mononuclear W and Mo complexes formulated as [M(CO)(NO)2(SO3F)3]? (M=W, Mo). Multinuclear NMR spectroscopic studies at natural abundance and 13C and 15N enrichment clearly indicate the presence of one CO ligand, two equivalent NO ligands, and two types of nonequivalent SO3F? groups in a 2:1 ratio. The IR and Raman spectra reveal that the two equivalent NO ligands have a cis conformation, thus indicating a fac structure. Density functional calculations at the B3LYP level of theory predict that these anions have a singlet ground state (1A′) with a Cs symmetry along with C–O and N–O vibrational frequencies that are in agreement with the experimental observations. Mulliken population analysis shows that the monovalent negative charge is dispersed on the bulky sphere, the surface of which is covered by all the negatively charged O and F atoms with charge densities much lower than SO3F?, suggesting that [fac‐M(CO)(NO)2(SO3F)3]? (M=W, Mo) are weakly nucleophilic and poorly coordinating anions. 相似文献
119.
O. Reuter R. Langley Dr. Wan Manshol Bin W. Zn 《Radiation Physics and Chemistry》1998,52(1-6):429-432
This paper presents anew design concept for a gamma irradiation plant for the continuous processing of pumpable liquids. Typical applications of such a plant include
- • * the irradiation vulcanisation of natural latex rubber
- • * disinfection of municipal sewage sludge for agricultural use
- • * sterilisation of liquids in the pharmaceutical and cosmetics industries
- • * industrial processing of bulk liquids
The authors describe the design and operation of the latex irradiator now operating on a small production scale in Malaysia and proposed developments.
The design allows irradiation processing to be carried out under an inert or other gaseous environment.
State-of-the-art computer control system ensures the fully automatic processing operation needed by industrial computers. 相似文献
120.
Dr. Bhagwan Swaroop 《Colloid and polymer science》1978,256(5):482-486
Summary The depressions in freezing point measurements in quaternary solubilized solutions or micro-emulsion in sodium oleate + phenol + benzene + water are measured. Maxima and minima were observed, Gibbs' phase rule was applicable, eutectic points were detected, congruent melting points were obtained, loose combination of molecules or clusters, were formed, phases of the system transferred and finally unstable emulsion separated out. This is contrary to the views ofMcBain who called these solutions as thermodynamically stable. The results were compared with the conductivity, stability and heat of solubilization-concentration measurements.
With 5 figures and 1 table 相似文献
Zusammenfassung Es wird die Gefrierpunktserniedrigung von quaternären solubilisierten Lösungen im System Natriumoleat-Phenol-Benzol-Wasser gemessen. Die verschiedenen Befunde (Maxima und Minima des Gefrierpunktes in Abhängigkeit von der Zusammensetzung, Anwendbarkeit der Gibbs'schen Phasenregel, Auftreten von Eutektika, kongruente Schmelzpunkte etc.) dienen zum Beweis, daß diese Lösungen thermodynamisch instabil sind.
With 5 figures and 1 table 相似文献