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111.
Steven H. Bertz 《Tetrahedron letters》1980,21(33):3151-3154
Copper reagents react with secondary and tertiary aldehyde tosylhydrazones to give unique, hindered cuprates which are alkylated in a one-flask procedure. 相似文献
112.
Wolfgang Schwack Bernd Brüger Steven Nyanzi 《Fresenius' Journal of Analytical Chemistry》1995,351(2-3):297-300
The differential pulse-polarographic (DPP) determination of both CS2 and COS gases, after their absorption in a methanolic piperidine reagent and the subsequent application of this technique to the residue analysis of dithiocarbamate fungicides is described. Rectilinear calibration curves for both CS2 and COS in the respective regions of 1.5–9.2 and 2.1–12.6 mol/l were obtained. The DPP method has been successfully applied to the determination of thiram residues on apples after a hot acid hydrolysis of the fruits. 相似文献
113.
For all oddv 3 the complete graph onvK
v
vertices can be decomposed intov – 2 edge disjoint cycles whose lengths are 3, 3, 4, 5,...,v – 1. Also, for all oddv 7,K
v
can be decomposed intov – 3 edge disjoint cycles whose lengths are 3, 4,...,v – 4,v – 2,v – 1,v.
Research supported by Australian Research Council grant A49130102 相似文献
114.
We give a simple proof of ergodicity of eigenfunctions of the Laplacian with Dirichlet boundary conditions on compact Riemannian manifolds with piecewise smooth boundaries and ergodic billiards. Examples include the Bunimovich stadium, the Sinai billiard and the generic polygonal billiard tables of Kerckhoff, Masur and Smillie. 相似文献
115.
Michael D. Westmoreland Benjamin W. Schumacher Steven C. Bailey 《International Journal of Theoretical Physics》1996,35(1):62-62
Reichenbach proposed a three-valued logic to describe quantum mechanics. In his development, Reichenbach presented three different negation operators without providing any criteria for choosing among them. In this paper we develop two three-valuedderived logics for classical systems. These logics are derived in that they are based on a theory of physical measurement. In this regard they have some of the characteristics of the quantum logic developed by Birkhoff and von Neumann. The theory of measurement used in the present development is the one used previously in developingbivalent derived logics for classical systems. As these systems are derived logics, many of the ambiguities possessed by systems such as Reichenbach's are avoided. 相似文献
116.
Steven Duplij 《Letters in Mathematical Physics》1996,37(4):385-396
We consider a nonstandard odd reduction of supermatrices (as compared with the standard even reduction) which arises in connection with the possible extension of manifold structure group reductions. The study was initiated by consideration of generalized noninvertible superconformal-like transformations. The features of even- and odd-reduced supermatrices are investigated together. They can be unified into some kind of sandwich semigroups. We also define a special module over even- and odd-reduced supermatrix sets, and the generalized Cayley-Hamilton theorem is proved for them. It is shown that the odd-reduced supermatrices represent semigroup bands and Rees matrix semigroups over a unit group.Alexander von Humboldt Fellow. On leave of absence from Theory Division, Nuclear Physics Laboratory, Kharkov State University, Kharkov 310077, Ukraine 相似文献
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