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91.
V. G. Mishra M. K. Das V. V. Raut S. Jeyakumar R. M. Sawant B. S. Tomar K. L. Ramakumar 《Journal of Radioanalytical and Nuclear Chemistry》2014,300(1):125-128
Two methods were developed for determination Li content in Li–Al alloy by employing ion chromatography (IC) and capillary electrophoresis (CE) without any prior separation of Al matrix. In absence of suitable certified reference material the two methods were used to validate each other. Using a high capacity column and a weaker eluent methane sulphonic acid, it was possible to separate Li in IC without eluting strongly retained Al. The method showed good precision and sensitivity and was extended for analysis of routine samples. In the case of CE using imidazole as co-ion, Li was detected in CE by indirect detection. In view of no interference from Al, samples were analyzed without any matrix separation. The CE method was used successfully for sample analysis and results were compared with IC results. 相似文献
92.
P. S. Ramanjaneyulu K. L. Pandey M. K. Saxena B. S. Tomar K. L. Ramakumar 《Journal of Radioanalytical and Nuclear Chemistry》2014,302(3):1231-1235
Boron was determined in ThO2 employing spectrophotometry using curcumin as complexing agent after dissolution with 85 % ortho phosphoric acid and separation of boron with 10 % 2-ethyl hexane 1,3 diol in CHCl3. The methodology was validated by employing ThO2 standards made from inter laboratory comparison experiments DAE, India. Absolute detection limit of the methodology was found to be 30 ng. Precision and accuracy of the methodology were found to be 4.2 and 2 % respectively. The expanded uncertainty in measurement of boron (at coverage factor 2) was estimated as per ISO guidelines employing bottom-up approach and it was found to be 9.2 %. 相似文献
93.
The synthesis of coumarin derivatives via Pechmann reaction using anhydrous FeCl3 as Lewis acid catalyst in ionic liquid medium has been carried out. The best results were obtained (yields as high as 89%) with ionic liquids having bis(triflic)imide as a counteranion. The ionic liquid could easily be recovered and reused. 相似文献
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95.
V. Kanwar S.K. Tomar 《International Journal of Mathematical Education in Science & Technology》2013,44(8):1112-1116
A new class of Euler's method for the numerical solution of ordinary differential equations is presented in this article. The methods are iterative in nature and admit their geometric derivation from an exponentially fitted osculating straight line. They are single-step methods and do not require evaluation of any derivatives. The accuracy and stability of the proposed methods are considered and their applicability to stiff problems is also discussed. 相似文献
96.
We present guaranteed and computable both sided error bounds for the discontinuous Galerkin (DG) approximations of elliptic problems. These estimates are derived in the full DG-norm on purely functional grounds by the analysis of the respective differential problem, and thus, are applicable to any qualified DG approximation. Based on the triangle inequality, the underlying approach has the following steps for a given DG approximation: (1) computing a conforming approximation in the energy space using the Oswald interpolation operator, and (2) application of the existing functional a posteriori error estimates to the conforming approximation. Various numerical examples with varying difficulty in computing the error bounds, from simple problems of polynomial-type analytic solution to problems with analytic solution having sharp peaks, or problems with jumps in the coefficients of the partial differential equation operator, are presented which confirm the efficiency and the robustness of the estimates. 相似文献
97.
Akshta Rajan Harish K. Yadav Vinay Gupta Monika Tomar 《Applied Physics A: Materials Science & Processing》2014,116(3):913-919
Ultraviolet photoconductivity in sol gel-derived ZnO thin film loaded with gold (Au) nanoparticle (NPs) is investigated. Au-NPs loaded ZnO thin film (Au-NPs/ZnO) is found to exhibit high photoconducting gain (K) of about 4.12 × 103 as compared to the bare ZnO thin film-based photodetector (4.9 × 101). The enhanced photoconductive gain of Au-NPs/ZnO detector has been achieved due to simultaneous lowering of dark current which occurs due to Schottky barrier effect originated after dispersing the Au NPs on the surface of ZnO thin film. The enhancement in photocurrent upon UV illumination is due to trapping of UV radiation via plasmonic effect caused by Au-NPs and subsequently coupling of absorbed light with the optical modes of underlying semiconducting ZnO surface. 相似文献
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100.
Divya Singh Amit Saxena Shri Prakash Pandey Sandeep Kumar Tomar K. Asokan D. Kanjilal Ranvir Kumar Bhaskar Bhattacharya 《Macromolecular Symposia》2009,277(1):8-13
In this paper, we report the ion beam interaction with a well explored ion conducting polymer electrolyte, viz., polyethylene oxide complexed with sodium iodide (PEO:NaI). Li3+ ions at 50 MeV were bombarded on the film at different flux. The conductivity modulation of the films has been reported due to interaction at different fluence. The increase in the total conductivity is explained in terms of the change in the number of charge carriers and the dielectric constant of the polymer electrolyte films. 相似文献