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31.
A kinetic study on the oxidation of V(IV) by chloramine-T (CAT) at pH 6.85 by N-bromo succinimide (NBS) in aqueous acetic acid–perchloric acid media and by N-iodo succinimide (NIS) in aqueous perchloric acid medium has been carried out. In all the systems studied the order with respect to the oxidant is unity. NBS and CAT oxidation reactions exhibited Michaelis–Menten type kinetics, and the NIS study indicated unit dependence on [substrate]. Independence on acidity has been observed in the case of CAT and NBS reactions, but NIS reactions exhibited inverse unit dependence on [acid]. Novel solvent influences have been noticed in the case of CAT reactions, but with NIS and NBS reactions retardation in the rate has been observed with an increase in the percentage of acetic acid. Plausible mechanisms consistent with the results have been postulated, and suitable rate laws in consonance with the postulated mechanisms have been derived. 相似文献
32.
Swayambhu Behera Justin Wilks Peter A. Dowben M. Sky Driver A.N. Caruso Jeffry A. Kelber 《Surface science》2010,604(21-22):L51-L54
We show that dopant impurities can be introduced in a controlled, site-specific manner into pre-deposited semiconducting boron carbide films. B―N bond formation has been characterized by X-ray photoelectron spectroscopy for semiconducting B10C2Hx films exposed to vacuum ultraviolet photons in the presence of NH3. Core level photoemission data indicate that B―NH2 bonds are formed at B sites bonded to other boron atoms (B―B), and not at boron atoms adjacent to carbon atoms (B―C) or at carbon atom sites. Nitridation obeys diffusion-limited kinetics. These results indicate that dopant species can be introduced in a controlled, site-specific manner into pre-deposited boron carbide films, as opposed to currently required dopant incorporation during the deposition process. 相似文献
33.
Theoretical and Mathematical Physics - To construct a phase-equivalent energy-dependent local potential corresponding to a sum of local and nonlocal interactions, we use a simple method for... 相似文献
34.
The ceramic oxide Na2Pb2Gd2W2Ti4Ta4O30 (NPGWT) was synthesized by the solid solution route. The formation of compound was checked by using X-ray diffraction and scanning electron microscope study. It is observed from both the studies that the material is a single phase and highly dense. The preliminary temperature variation of the dielectric study reveals ferroelectric to paraelectric phase transition much above the room temperature. The polarization study of the material further confirms the presence of ferroelectricity in the studied compound. The transport property of the material was carried out by using the impedance spectroscopy technique. From both impedance and modulus analysis, it is confirmed that conduction mechanism in the material is due to the hopping motion of charge carrier. To strengthen the hopping motion of charge carrier in the material frequency dependence, ac conductivity is carried out. 相似文献
35.
D. Behera 《Journal of luminescence》2008,128(10):1577-1586
Zinc oxide doped with Al (AZO) thin films were prepared on borosilicate glass substrates by dip and dry technique using sodium zincate bath. Effects of doping on the structural and optical properties of ZnO film were investigated by XRD, EPMA, AFM, optical transmittance, PL and Raman spectroscopy. The band gap for ZnO:Al (5.0 at. wt.%) film was found to be 3.29 eV compared with 3.25 eV band gap for pure ZnO film. Doping with Al introduces aggregation of crystallites to form micro-size clusters affecting the smoothness of the film surface. Al3+ ion was found to promote chemisorption of oxygen into the film, which in turn affects the roughness of the sample. Six photoluminescence bands were observed at 390, 419, 449, 480, 525 and 574 nm in the emission spectra. Excitation spectra of ZnO film showed bands at 200, 217, 232 and 328 nm, whereas bands at 200, 235, 257 and 267 nm were observed for ZnO:Al film. On the basis of transitions from conduction band or deep donors (CB, Zni or VOZni) to valence band and/or deep acceptor states (VB, VZn or Oi or OZn), a tentative model has been proposed to explain the PL spectra. Doping with Al3+ ions reduced the polar character of the film. This has been confirmed from laser Raman studies. 相似文献
36.
Aharonian F Akhperjanian AG Barres de Almeida U Bazer-Bachi AR Becherini Y Behera B Beilicke M Benbow W Bernlöhr K Boisson C Bochow A Borrel V Braun I Brion E Brucker J Brun P Bühler R Bulik T Büsching I Boutelier T Carrigan S Chadwick PM Charbonnier A Chaves RC Chounet LM Clapson AC Coignet G Costamante L Dalton M Degrange B Deil C Dickinson HJ Djannati-Ataï A Domainko W Drury LO Dubois F Dubus G Dyks J Egberts K Emmanoulopoulos D Espigat P Farnier C Feinstein F Fiasson A Förster A Fontaine G 《Physical review letters》2008,101(17):170402
In the past few decades, several models have predicted an energy dependence of the speed of light in the context of quantum gravity. For cosmological sources such as active galaxies, this minuscule effect can add up to measurable photon-energy dependent time lags. In this Letter a search for such time lags during the High Energy Stereoscopic System observations of the exceptional very high energy flare of the active galaxy PKS 2155-304 on 28 July 2006 is presented. Since no significant time lag is found, lower limits on the energy scale of speed of light modifications are derived. 相似文献
37.
P.D. Shidling N. Madhavan V.S. Ramamurthy S. Nath N.M. Badiger Santanu Pal A.K. Sinha A. Jhingan S. Muralithar P. Sugathan S. Kailas B.R. Behera R. Singh K.M. Varier M.C. Radhakrishna 《Physics letters. [Part B]》2008
Evaporation residue (ER) cross sections and gamma multiplicity distributions have been measured for 16O + 184W and 19F + 181Ta systems in the excitation energy range of 50–90 MeV, leading to the same compound nucleus 200Pb∗. Comparison of experimental results of both the systems shows that ER cross sections and moments of gamma multiplicity distribution of 16O + 184W system are significantly higher than those of 19F + 181Ta system at higher excitation energies. Present measurements directly shows the experimental signature of entrance channel effect even with the systems which are not very different with respect to their entrance channel mass asymmetry. It is further demonstrated that the reduction in the ER cross section and moments of spin distribution for 19F + 181Ta system is mainly due to the suppression of fusion of higher l values. 相似文献
38.
Samir Kumar Sarkar Meenakshi Pegu Santosh Kumar Behera Siva Krishna Narra Pakkirisamy Thilagar 《化学:亚洲杂志》2019,14(24):4431-4431
39.
Synthesis of tricyclic systems related to crotogoudin from a simple aromatic precursor has been described. Oxidative dearomatization, tandem retro-Diels–Alder/Diels–Alder reaction and ring-closing metathesis are the key features of our approach. 相似文献
40.
Ratikanta Behera Ashish Kumar Nandi Jajati Keshari Sahoo 《Numerical Linear Algebra with Applications》2020,27(5)
The notion of the Drazin inverse of an even‐order tensors with the Einstein product was introduced, very recently [J. Ji and Y. Wei. Comput. Math. Appl., 75(9), (2018), pp. 3402‐3413]. In this article, we further elaborate this theory by establishing a few characterizations of the Drazin inverse and ‐weighted Drazin inverse of tensors. In addition to these, we compute the Drazin inverse of tensors using different types of generalized inverses and full rank decomposition of tensors. We also address the solution of multilinear systems by using the Drazin inverse and iterative (higher order Gauss‐Seidel) method of tensors. Besides these, the convergence analysis of the iterative technique is also investigated within the framework of the Einstein product. 相似文献