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K. Venkatesh Sumit Chhillar Granthali S. Kamble Shailaja P. Pandey Manisha Venkatesh Sanjukta A. Kumar Sanjiv Kumar R. Acharya P. K. Pujari A. V. R. Reddy 《Journal of Radioanalytical and Nuclear Chemistry》2014,302(3):1425-1428
Boron is an important element in nuclear technology. A comparative study was carried out for the determination of boron in borosilicate glass, boron carbide and graphite samples by wet-chemical and nuclear analytical methods. Wet chemical methods namely titrimetry, Inductively Coupled Plasma Mass Spectrometry and ICP Optical Emission Spectrometry and nuclear analytical methods namely Particle Induced Gamma-Ray Emission and Nuclear Reaction Analysis were used. Boron concentrations were in trace (mg kg?1) level in graphite and percentage level in borosilicate glass and boron carbide. 相似文献
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Pritty Rao G. L. N. Reddy S. Vikram Kumar J. V. Ramana N. Chattopadhyay A. K. Basu Seema Srivastava R. K. Sarin V. S. Raju Sanjiv Kumar 《Journal of Radioanalytical and Nuclear Chemistry》2012,294(1):127-130
The paper describes the simultaneous determination of 14N and 15N isotopes in opium by proton induced γ-ray emission (PIGE) technique. The isotopic ratio of 14N and 15N is a useful parameter for assigning provenance of (seized) illicit drugs. The measurement, non-destructive in nature, is performed on pellets made up of opium powders and is based on the prompt detection of 2.313 and 4.4 MeV γ-rays emanating from 14N(p,p′γ)14N and 15N(p,αγ)12C nuclear reactions respectively, induced simultaneously by 3.6–3.8 MeV proton beam. Positive as well as negative deviations from the natural isotopic abundance (99.63:0.37) were observed in the samples. The precision of the measurements is about 4%. The methodology provides an easy and rapid approach to determine the isotopic ratio of 14N and 15N and has been used for the first time in the analysis of opium. 相似文献
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Sumit Arora Manil T. Mohan Jaydev Dabas 《Mathematical Methods in the Applied Sciences》2023,46(1):531-559
This article deals with the approximate controllability problem for fractional evolution equations involving noninstantaneous impulses and state-dependent delay. In order to derive sufficient conditions for the approximate controllability of our problem, we first consider the linear-regulator problem and find the optimal control in the feedback form. By using this optimal control, we develop the approximate controllability of the linear fractional control system. Further, we obtain sufficient conditions for the approximate controllability of the nonlinear problem. In the end, we provide a concrete example to support the applicability of the derived results. 相似文献