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81.
In this paper the superstability of the Cauchy equation can be proved for complex valued functions on commutative semigroup under some suitable conditions. Furthermore, in this note, we give a partial affirmative answer to problem 18, in the 31st ISFE.  相似文献   
82.
This presented study is to make comparison of cross sections to produce 117Sb and 90Nb via different reactions with particle incident energy up to 70 MeV as a part of systematic studies on particle-induced activations on enriched Sn, Y2O3 and ZrO2 targets, theoretical calculation of production yield, calculation of required thickness of target and suggestion of optimum reaction to produce Antimony-117 and Niobium-90.  相似文献   
83.
The density, sound velocity, and conductivity measurements were performed on aqueous solutions of sodium dodecyl sulfate (C12H25SO4Na) or sodium dodecyl sulfonate (C12H25SO3Na) in the absence and presence of poly(ethylene glycol) (PEG) at different temperatures. Changes in the apparent molar volumes and isentropic compressibilities upon micellization were derived using a pseudophase-transition approach and the infinite dilution apparent molar properties of the monomer and micellar form of C12H25SO4Na and C12H25SO3Na were determined. Variations of the critical micelle concentrations (CMCs) of both surfactants in the solutions investigated with temperature were obtained from which thermodynamic parameters of micellization were estimated. It was found that at low temperature the micelle formation process is endothermic and therefore, this process must be entropically driven. However, upon increasing the temperature, the enthalpic factor becomes more significant and, at temperatures higher than 303.15 K the micellization is enthalpy driven. The interactions between C12H25SO4Na/C12H25SO3Na and PEG were studied and it was found that sodium alkyl sulfonates were seen to interact more weakly than their sulfate analogues.  相似文献   
84.
In this paper we discuss interacting particles in an external magnetic field. By comparing the Schr?dinger equation of three interacting particles with the associated Laguerre differential equation, we obtain the energy spectrum which corresponds to indices ni and mi. Finally by using the so called factorization method we obtain the raising and lowering operators. These operators are supersymmetric structures related to the Hamiltonian partner. Also these operators lead to the realization of Heisenberg Lie superalgebras with two, four and six supercharges.  相似文献   
85.
Motivated by the recent work of Elizalde et al. [E. Elizalde, S. Nojiri, S.D. Odintsov, D. Saez–Gomez, V. Faraoni, Phys. Rev. D 77 (2008) 106005], we generalize their work to the non-flat case. We consider a universe filled with matter and show that it is possible to obtain both inflation and accelerated expansion at late times by using a single scalar field. Realistic examples are worked out in order to illustrate this fact. Then we extend the problem to the interacting case.  相似文献   
86.
Advection equations with delay are appeared in the modeling of the dynamics of structured cell populations. In this article, we construct an efficient two-dimensional multistep collocation method for the numerical solution of a class of advection equations with delay. Equations with aftereffect and equations with both aftereffect and retardation of a state variable are considered. Computability of the algorithm and convergence properties of the proposed numerical method are analyzed for solutions in appropriate Sobolev spaces, and it is shown that the proposed scheme enjoys the spectral accuracy. Numerical examples are given and comparison with other existing methods in the literature is made to demonstrate the efficiency, superiority and high accuracy of the presented method.  相似文献   
87.
Celikbas  Olgur  Liang  Li  Sadeghi  Arash  Sharif  Tirdad 《数学学报(英文版)》2023,39(3):439-458
Acta Mathematica Sinica, English Series - In this paper we are concerned with absolute, relative and Tate Tor modules. In the first part of the paper we generalize a result of Avramov and...  相似文献   
88.
89.
A series of aza‐polycyles containing octahydroacridine core were prepared via an intramolecular aza‐Diels‐Alder reaction of a dimerized citral with various aromatic amines. This reaction is efficiently catalyzed by InCl3 at ambient temperature to afford the corresponding cyclized products in moderate to good yields.  相似文献   
90.
New centrosymmetric trinuclear zinc(II) complex {[Zn(μ-ONN)(μ2-O)(μ-OO)]2Zn} has been synthesized by the reaction of a potentially ONN tridentate Schiff base ligand, and N,N-dimethylethylendiamin, with Zn(OAc)2·2H2O in methanol, in the refluxed conditions and characterized by elemental analysis, FT-IR and UV–Vis spectroscopy. Single crystal X-ray structure analysis reveals a trinuclear complex {[Zn(μ-ONN)(μ2-O)(μ-OO)]2Zn} with zinc(II) ions connected by three different bridges, (μ-ONN) of the Schiff base ligand, μ2-O and μ-OO of the acetate. The complex is centrosymmetric, with one of the Zn atoms located at the inversion center. While the central Zn(II) ion is six-coordinated, the coordination number of the other Zn(II) ions is five. Finally, the {[Zn(μ-ONN)(μ2-O)(μ-OO)]2Zn} complex was thermally decomposed in air at 700 °C resulted in ZnO nano crystalites with the average size of 42 nm. The antibacterial activity of ligand and its zinc(II) complex were tested against gram-positive and gram-negative bacteria. The ligand showed higher activity than its zinc(II) complex.  相似文献   
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