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41.
The Ramanujan Journal - In this paper, we develop a finite field analogue for one of the Lauricella series, $$F^{(n)}_A$$ . Extending results of Greene, a finite field analogue for the multinomial... 相似文献
42.
Sanjay Jadhav Gajanan Rashinkar Rajashri Salunkhe Arjun Kumbhar 《Tetrahedron letters》2017,58(33):3201-3204
A simple, efficient and metal-free route for the synthesis of dissymmetric ketones through Suzuki type cross-coupling reaction has been established. This strategy signifies an attractive, cost-effective and operationally convenient tool for the synthesis of a wide range of dissymmetric ketones. Although conventional routes for the synthesis of ketones have been widely used, the potential challenge with these methods is functional group tolerance. The reported metal-free method represents a reaction with moderate functional group tolerance. The procedure is operationally convenient and shows broad substrate scope with good to excellent product yields. 相似文献
43.
Arjun Singh Tirupati Chander Sharma Prateek Kishore 《Journal of Thermal Analysis and Calorimetry》2017,129(3):1403-1414
In this article, thermal degradation behavior of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB)-based plastic-bonded explosives (PBXs) bonded with a different fluoropolymer matrices namely indigenous poly(vinylidene fluoride-chlorotrifluoroethylene) (FKM), FK 800, fluoroplastic F-32L and fluororubber SKF 32 was investigated through non-isothermal thermogravimetric analysis (TG) technique under nitrogen atmosphere. It was observed that the mass loss of PBXs containing FKM and FK 800 matrices occurred in three steps. The mass loss of PBXs containing fluoroplastic F-32L and fluororubber SKF 32 occurred in two steps. Kinetics were investigated through non-isothermal TG at different heating rates for the first step of degradation by means of model-free Flynn–Wall–Ozawa (FWO) and Kissinger–Akahira–Sunose (KAS) methods. The activation energies calculated by applying FWO method are in good agreement and very close to those obtained by KAS method. The results revealed that the effect of the polymer matrices on the thermal degradation reaction of TATB was significantly observed especially different outcomes of kinetic parameters. The reaction models for degradation were also studied by Criado method. The reaction models are probably best described by the power law and diffusion models. 相似文献
44.
Sulfonyl fluoride electrophiles have found significant utility as reactive probes in chemical biology and molecular pharmacology. As warheads they possess the right balance of biocompatibility (including aqueous stability) and protein reactivity. Their functionality is privileged in this regard as they are known to modify not only reactive serines (resulting in their common use as protease inhibitors), but also context-specific threonine, lysine, tyrosine, cysteine and histidine residues. This review describes the application of sulfonyl fluoride probes across various areas of research and explores new approaches that could further enhance the chemical biology toolkit. We believe that sulfonyl fluoride probes will find greater utility in areas such as covalent enzyme inhibition, target identification and validation, and the mapping of enzyme binding sites, substrates and protein–protein interactions. 相似文献
45.
Arjun Berera 《Contemporary Physics》2013,54(1):33-49
In the past decade, the importance of dissipation and fluctuation to inflationary dynamics has been realized and has led to a new picture of inflation called warm inflation. Although these phenomena are common to condensed matter systems, for inflation models their importance has only recently started to be appreciated. The article describes the motivation for these phenomena during inflation and then examines their origins from first principles quantum field theory treatments of inflation models. Cosmology today is a data intensive field and this is driving theory to greater precision and predictability. This opens the possibility to consider tests for detecting observational signatures of dissipative processes, which will be discussed. In addition, it will be discussed how particle physics and cosmology are now working in tandem to push the boundaries of our knowledge about fundamental physics. 相似文献
46.
V S Ramamurthy D P Mahapatra R T Yadav G V Ravi Prasad Arjun Gopalakrishna 《Pramana》1992,39(5):L583-L587
A conventional tandem Van de Graaff accelerator is used to produce charged carbon cluster beams. The unique capability of
the method for studying highly charged clusters unaccessible to other methods of producing cluster beams is demonstrated. 相似文献
47.
Hornblende which occurs in igneous and metamorphic rocks is well suited for age determination by the fission track method. The tracks which are readily etched in hydrofluoric acid are annealed in 1 hr at 530° C. Extrapolation of the experimentally determined temperatures suggest that a temperature of 200° C for one m.y. will erase all the tracks present before the heating. Fission track ages of hornblende agree with the main orogenic metamorphic cycles. 相似文献
48.
Arjun K. Gopta 《数学物理学报(B辑英文版)》1999,19(1)
1IntroductionLetnbeanormalt--variatepopulationandXj,j=1,'',t(t23)bethej--thvariateinn.Letthesetofvariatesxl,''txtbepartitionedintoqmutuanyexclusivesubsetsofwhich.say,esubsetscontainexactlyonevariateandthereasoningk=q--esubsets(k21)containti,''ttkvariatesrespectively,wheref.22(y=1,''tk;e Z:=,t.=f).Nogeneralityislostinassumingthatthetvariatesareorderedsothatthefirst,belongtothe,subsetscontainingoneyaxiateeach,andnexttivariatesbelongto(I 1)--fhsubset,'',thelasttivariatestotheq--thsubset,whe… 相似文献
49.
In this paper, a new measure of dependence is proposed. Our approach is based on transforming univariate data to the space where the marginal distributions are normally distributed and then, using the inverse transformation to obtain the distribution function in the original space. The pseudo-maximum likelihood method and the two-stage maximum likelihood approach are used to estimate the unknown parameters. It is shown that the estimated parameters are asymptotical normally distributed in both cases. Inference procedures for testing the independence are also studied. 相似文献
50.