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101.
102.
103.
In the present paper we derive a number of key formulas involving fractional derivatives for the H-function of several variables, which was introduced and studied in a series of papers by 11., 12., 13., 14., 15., 9., 261–277].We make use of the generalized Leibniz rule for fractional derivatives in order to obtain one of the aforementioned results, which involves a product of two multivariable H-functions. Each of these results is shown to apply to yield interesting new results for certain multivariable hypergeometric functions and, in addition, several known results due, for example, to J. L. Lavoie, T. J. Osler and R. Tremblay [SIAM Rev.18 (1976), 240–268], 4., 5., 371–382] and R. K. Raina and C. L. Koul [Jñānābha7 (1977), 97–105]. 相似文献
104.
Effect of hydrotropes viz. sodium benzene sulfonate (NaBS), sodium toluene sulfonate (NaTS) and sodium xylene sulfonate (NaXS) on the micellization, phase behavior and structure of poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (PEO-PPO-PEO) triblock copolymer L62 in aqueous solution was studied by surface tension, dye spectral, cloud point and small angle neutron scattering measurements. The addition of hydrotropes increased the critical micelle concentration (CMC) of L62 which appears to be logistic as the added hydrotrope enhances the solubility of PPO moiety (and PEO) making it behave like a more hydrophilic block copolymer that would micellize at high copolymer concentration. Partial phase diagram of L62 in water shows two cloud point (CP) in the concentration range (0-10 wt.%). Addition of hydrotropes shifts the L62 concentration range showing double cloud points at lower side of concentration; sodium xylene sulfonate (NaXS) being more effective. SANS data for L62 in the presence of 0.4 and 0.8 M NaXS at temperatures <30 °C showed unimers which are fully dissolved Gaussian chains. The unimer-to-micelle transition takes place when temperature is increased. It is found that SANS data for L62 in the presence of 0.4 M NaXS (40 and 50 °C) and 0.8 M NaXS (45 and 50 °C) correspond to ellipsoidal structure of micelles. 相似文献
105.
D. P. Goyal J. S. Braich S. Murlithar B. P. Singh H. R. Verma 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1995,35(3):155-161
TheL X-ray production cross sections in gold by 60 to 72 MeV O5+ ions and 58 to 87 MeV Ni5+-ions have been measured. TheL-subshell ionization cross sections derived from these experimental results have been compared with the direct ionization theories viz. plane wave Born approximation (PWBA) theory and modified perturbed-stationary-state theory with energy loss, Coulomb deflection and relativistic effects (MECPSSR). A new procedure has been described to account for the change in the yield ratioLβ1/Lβ2, 15 with energy, for Ni5+-ion impact on gold. TheL sub-shell ionization cross sections have been derived fromLβ1,Lβ4 andLβ2, 15 lines of theLβ group in addition to those calculated by the conventional Datz TRY3 technique usingLα,Lγ1 andLγ2, 3 X-ray lines. From the shift in the energies of variousL X-ray lines and changes in their intensities, 3 and 5 spectator vacancies in theM- andN-shells in gold have been estimated with O5+-ion impact while 7, 20 and 4 to 6 spectator vacancies have been inferred in theM-,N-andO-shells respectively with Ni5+-ion impact in the energy range of the projectiles undertaken in the present studies. 相似文献
106.
The equilibrium constants of the complexation reactions of Cr(VI), Mo(VI) and W(VI) with 8-hydroxyquinoline-5-sulphonic acid (OXS), 7-phenylazo-8-hydroxyquinoline-5-sulphonic acid (PAZOXS), 7-(4-sulphophenylazo)-8-hydroxyquinoline-5-sulphonic acid (SPAZOXS) and 7-(4-sulphonaphthylazo)-8-hydroxyquinoline-5-sulphonic acid (SNAZOXS) have been determined by potentiometric pH titration. The values in the case of chromate are different from those for molybdate and tungstate. The order of stabilities is OXS > PAZOXS > SPAZOXS > SNAZOXS. 相似文献
107.
Precise density and viscosity data at 15, 25 and 35°C for solutions of glycine, DL-alanine, L-threonine, -alanine, -aminobutyric acid and -aminocaproic acid in water and in (1m, 3m, 5m) aqueous potassium thiocyanate were measured and the limiting apparent molar volumes V
o
and the B-coefficients calculated. The V
o
and B values were split into the contributions from the NH
3
+
,COO– and CH2 groups. These data are rationalized on the basis of hydrophillic and hydrophobic interactions between the various groups present in these solutions.Abstracted from the Ph.D Thesis of R. K. Goyal, University of Delhi, 1990. 相似文献
108.
This paper deals with anisotropic behavior of thermal expansivity (α) of poly(ether-ether-ketone) (PEEK) sample prepared by compression molding above the melting point of polymer. The α was determined using thermo mechanical analyzer (TMA) for the temperature interval 50-250 °C in expansion mode. It is found that out-of-plane thermal expansivity (αz) is 3.8-fold of the in-plane thermal expansivity (αxy) below the glass transition temperature (Tg) of PEEK while αz is decreased to 1.8-fold of the αxy above the Tg. Moreover, the average αz over the range studied is about 2.2-fold of the αxy. This anisotropic behavior may be attributed to the alignment of polymer spherulites and chains along in-plane direction due to compressive forces under hot compression molding. 相似文献
109.
R.N. Goyal Anna Brajter-Toth Glenn Dryhurst 《Journal of Electroanalytical Chemistry》1982,133(2):287-297
The electrochemical and peroxidase/H2O2 oxidation of 9-methyl uric acid has been studied over a wide pH range. Electrochemical, spectral, kinetic and analytical results support the view that the electrochemical and enzymic oxidations proceed by virtually identical mechanisms. 相似文献
110.
Sandeep Goyal Anang Pal Mangilal Chouhan Mukesh Gangar Sharad Sarak Vipin A. Nair 《Tetrahedron letters》2017,58(4):346-348
An efficient strategy for a one-pot, single step synthesis of β-lactams employing an imidazolidinone based chiral auxiliary with various aldimines via asymmetric Mannich-type reaction has been described. 相似文献