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31.
Sabri Cevik Bihter Şaşmaz Cengiz Yenikaya Ferdağ Çolak Musa Sari Orhan Büyükgüngör 《Russian Journal of Inorganic Chemistry》2010,55(4):494-500
The hydrothermal reaction of a mixture of V2O5, VCl3, 2,5-pyridinedicarboxylic acid and diluted H2SO4 for 68 h at 180°C gives a blue colored solution which yields prismatic blue crystals of IV 2 IV O2(SO4)2(H2O)6] (1) in 32% yield (based on V). Complex 1 was investigated by means of elemental analysis (C, H and S), TGA, FT-IR, manganometric titration, Single Crystal X-ray Diffraction Methods and also comparative antimicrobial activities. Crystal data for the compound: monoclinic space group P21/c and unit cell parameters are a = 7.3850(12) Å, b = 7.3990(7) Å, c = 12.229(2) Å, β = 108.976(12)° and Z = 2. Although structure of 1 as a natural mineral has been previously determined, this work covers new preparation method and full characterization of 1 along with comparison of antibacterial activity between 1 and the commercial vanadium(IV) oxide sulfate hydrate compounds, VOSO4 · xH2O (Riedel-de Haën and Alfa Aesar brand names). 1 was evaluated for the antimicrobial activity against gram-positive, gram-negative bacteria, yeasts and mould compared with the commercial VOSO4 · xH2O compounds. 1 showed weak activity against bacteria Bacillus cereus, Nocardia asteroides and yeast Candida albicans. A good antimicrobial activity was recorded against Cirtobacter freundii (15 mm). There are only a few reproducible well-defined vanadium(IV) starting materials to use for exploring the synthesis of new materials. VCl4, VO(acac)2, VOSO4 · xH2O and [V(IV)OSO4(H2O)4] · SO4 · [H2N(C2H4)2NH2] are common starting materials for such applications. In addition to these compounds, 1 can be used as an oxovanadium precursor. 相似文献
32.
An intense laser field effect on the intersubband transitions in quantum wells is theoretically investigated within the framework of the effective-mass approximation. Results obtained show that intersubbband optical transitions and energy levels in quantum wells can be significantly modified and controlled by an intense laser field. PACS 71.55.Eq; 73.21.Fg; 78.67.De 相似文献
33.
Sari M. Kunnari Raija Oilunkaniemi Risto S. Laitinen Markku Ahlgren 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(10):o610-o611
The novel title tetraselenacalix[4]arene, C16H8S4Se4 or [(C4H2S)Se]4, has a centrosymmetric cyclic molecular structure with approximate C2h molecular symmetry. The four thienyl rings are joined together by Se bridges and exhibit a syn–syn–anti–anti arrangement around the molecule. The lattice consists of skewed stacks of molecules, with chalcogen–chalcogen close contacts binding the stacks together, forming a two‐dimensional network of molecules. 相似文献
34.
Murat Sari Gürhan Gürarslan Asuman Zeytinoğlu 《Numerical Methods for Partial Differential Equations》2011,27(5):1313-1326
In this article, up to tenth‐order finite difference schemes are proposed to solve the generalized Burgers–Huxley equation. The schemes based on high‐order differences are presented using Taylor series expansion. To establish the numerical solutions of the corresponding equation, the high‐order schemes in space and a fourth‐order Runge‐Kutta scheme in time have been combined. Numerical experiments have been conducted to demonstrate the high‐order accuracy of the current algorithms with relatively minimal computational effort. The results showed that use of the present approaches in the simulation is very applicable for the solution of the generalized Burgers–Huxley equation. The current results are also seen to be more accurate than some results given in the literature. The proposed algorithms are seen to be very good alternatives to existing approaches for such physical applications. © 2010 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 27: 1313‐1326, 2011 相似文献
35.
Branko Sarić 《Czechoslovak Mathematical Journal》2011,61(4):1017-1022
In this paper a full totalization is presented of the Kurzweil-Henstock integral in the multidimensional space. A residual function of the total Kurzweil-Henstock primitive is defined. 相似文献
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37.
It is often asserted that superconducting systems are manifestations of quantum mechanics on a macroscopic scale. In this review article it is demonstrated that this quantum assertion is true within the framework of the microscopic theory of superconductivity. 相似文献
38.
39.
Sirpa Peräniemi Sari Hannonen Heikki Mustalahti Markku Ahlgrén 《Fresenius' Journal of Analytical Chemistry》1994,349(7):510-515
The adsorption of arsenic, selenium and mercury from aqueous solutions onto zirconium-loaded activated charcoal was studied as a function of adsorption time, amount of adsorbent, pH, concentration of adsorbates, sample volume and the oxidation states of the adsorbates. The cross-interference of the analytes was also investigated. Loaded filters were measured by energy-dispersive X-ray fluorescence spectrometry (EDXRF) and the amount of the unadsorbed analytes were determined by vapour generation atomic absorption spectrometry (VGAAS). 相似文献
40.
If the set of spreading models of a Banach space is countable (up to equivalence), then it cannot contain a strictly increasing infinite chain of spreading models generated by normalized weakly null sequences. Moreover, such a space must have a spreading model which is `close' to or for some .