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991.
In this paper we study a class of separable Banach spaces which can be approximated by certain special finite-dimensional
subspaces. This class is characterized in Theorem 1.1, from which it follows that the space of continuous scalar-valued functions
on a compact metric space always belongs to this class, and that every member of this class has a monotone basis.
Supported in part by N.S.F. Grant 11-5020.
Supported in part by N.S.F. Grant GP-3579. 相似文献
992.
Glycinehydroxamic acid, C2H6N2O2 (NH2CH2C(O)NHOH), was synthesized and its crystal and molecular structure determined by single-crystal X-ray diffraction methods. The crystals are monoclinic:P2
1/c C
2h
5
, No. 14),a=5.682(2),b=7.133(2),c=9.540(3) Å,=104.38(4)°,Z=4. The structure has been solved by direct phase determination methods, and refined to anR value of 0.042 for 633 nonzero independent amplitudes. The molecule of the title compound exists in the structure as a zwitterion, NH
3
+
-CH2-C(O)-N-OH. The hydroxamate group is planar and the N (amino) atom, from the glycine part of the molecule, deviates by 1.43 Å from the best molecular plane defined by O(1), N(1), C(1), and O(2) atoms, respectively.The molecules are held together by a network of N+-HO, N+-H¯N, and O-HO hydrogen bonds. 相似文献
993.
1H NMR studies of mixed-ligand iron (III) dithiocarbamates have been carried out using the following ligands: N,N-diethyldithiocarbamate, morpholinyl-N-, and piperidyl-N-carbodithioate. The ligand exchange equilibria gave all species of the general formula Fe(dtc)n(dtc′)3?n, where n = 0-3 with nearly random statistical distribution of Fe(Et2dtc)n(morphdtc)3?n complexes. Magnetic moments of the mixed-ligand complexes have been determined. Both the magnetic moment and isotropic shift temperature dependences confirmed the cross-over properties of these mixed-ligand complexes. 相似文献
994.
Marian Matłoka 《Fuzzy Sets and Systems》1985,15(3):255-262
In this paper a Fixed-Point Theorem and an application is presented. 相似文献
995.
In this paper new topological concepts connected with fuzzy multi-valued functions theory-as presented in the first part of this work-are introduced and their properties are investigated. As will be shown in future papers these concepts and properties are indispensable in connection with the analysis of fuzzy economic systems. 相似文献
996.
The Hermite series estimate of a density f?Lp, p > 1, convergessin the mean square to f (x) for almost all x? |R, ifN (n) → ∞ and N (n) / n2 → ) as n → ∞, where N is the number of the Hermite functions in the estimate while n is the number of observations. Moreover, the mean square and weak consistency are equivalent. For m times differentiable densities, the mean squares convergence rate is O(n?(2m?1)/2m). Results for complete convergence are also given. 相似文献
997.
Nonoscillation,oscillation and growth of solutions of nonlinear difference equations of second order
Błażej Szmanda 《Journal of Mathematical Analysis and Applications》1985,109(1):22-30
Sufficient conditions are obtained which guarantee that all solutions (or all bounded solutions) of a class of second order nonlinear difference equations are nonoscillatory. Oscillation criteria and theorems concerning the growth of solutions are also given. 相似文献
998.
This paper deals with some problems of the control of fuzzy systems described by means of a relational equation of the type: Xκ + 1 = Uκ ° Xκ ° R. The basic aspects such as mutual identification and control, stabilization control, control with constraints, generation of control rules of a fuzzy logic controller, important from the theoretical and applicational point of view are discussed and illustrated by means of numerical examples. 相似文献
999.
Wiesław Strek 《Chemical physics letters》1979,61(3):611-613
A quantum-mechanical theory of the magnetic field effect on radiationless transitions in an isolated molecule is presented. The mechanism of this phenomenon is a second-order process relying on the simultaneous radiationless relaxation of an excited electronic state and the interaction of the molecule with a constant uniform magnetic field. 相似文献
1000.
The crystal and molecular structure of glycinium diphenylphosphate, C14H16NO6P, has been determined by X-ray methods. The crystals are orthorhombic:Pbca (No. 61),a=11.412(3),b=24.624(7),c=10.775(3) Å,Z=8. The structure was solved by direct methods and refined to anR value of 0.043 for 1289 nonzero independent amplitudes. The molecule exists in the structure as+NH3CH2CO2H,(C6H5O)2PO
2
–
and is planar except for the N atom, which deviates by 0.49 Å from the plane defined by C(1), C(2), O(5), and O(6) atoms, respectively. The conformation of the diphenylphosphate anion isgauche with respect to both P-O ester bonds. There are four crystallographically independent hydrogen bonds, three of the N-HO type and one of the O-HO type. 相似文献