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1.
B. S. Narwade P. G. Gawali Rekha Pande G. M. Kalamse 《Journal of Chemical Sciences》2005,117(6):673-676
Dielectric constant (ε’) and dielectric loss (ε") of n-propyl alcohol (PA), ethylenediamine (EDA) and their binary mixtures,
for different mole fractions of ethylenediamine have been experimentally measured at 11.15 GHz microwave frequency. Values
of density (ρ), viscosity (η) and square refractive index (n
D
2
) of binary mixtures as well as those of pure liquids are reported. Excess square refractive index, viscosity and activation
energy of viscous flow have also been estimated. These parameters have been used to explain the formation of complexes in
the system. 相似文献
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In the present work, an experimental investigation of heat transfer enhancement parameters of the oscillating flow heat exchanger under different frequencies, tidal displacement, and heat fluxes is carried out. The effect of different parameters on experimental effective thermal conductivity and convective heat transfer coefficient in cooling region is studied using correlations given by different researchers. A correlation for experimental effective thermal conductivity in terms of S2√ω is derived based on experimental data. This correlation is useful for predicting the optimum value of S2√ω before onset of turbulence. 相似文献
4.
Murali M. S. Gawali Santosh L. Hassan P. A. Gujar R. B. 《Journal of Radioanalytical and Nuclear Chemistry》2019,320(3):577-585
Journal of Radioanalytical and Nuclear Chemistry - The behavior of three symmetrical sulphoxides, R2SO, where R?=?Di-(2-ethylhexyl) (DEHSO), R?=?dihexyl (DHSO) or... 相似文献
5.
Salunke Gawali S. Dalvi R. Ah Khursheed Rane S. 《Journal of Thermal Analysis and Calorimetry》2004,76(3):801-812
Syntheses of phthiocol complexes with Cu(II) in inert media resulted in anhydrous monomer Cu-4: [Cu(NQ)2] and dimer Cu-5: [Cu(NQ)(NSQ)]2, however synthesis in air generates polymeric hydrated Cu-6: [Cu(NQ)2(H2O)2]n. Media and colligation give rise to charge transfers in coordination compounds and lead to different redox ligations of 3-methyl-2-hydroxy-1,4-naphthoquinone.
These redox forms are determined from quantitization of activation energies (E
a) of different pyrolytic steps in TG using the rising temperature expression of Coats and Redfern. 'Tyrosinase'-type mechanism
is discussed for the redox-type ligation. Characteristic six-line EPR signals of dimeric Cu-5 lead to zero field splitting
parameters D=0.01608 cm-1and E=0.01576 cm-1. Cu-6 shows molecular association through hydrogen bonding. Variable temperature magnetic measurement data of Cu-6 from 6
to 300 K is fitted to the polymeric expression of Bonner and Fisher model. The best fit was obtained with antiferrromagnetic
exchange coupling constantJ=-2 cm-1, g=2.2 having R=4.2·10-4.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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Enachescu C Linares J Varret F Boukheddaden K Codjovi E Salunke SG Mukherjee R 《Inorganic chemistry》2004,43(16):4880-4888
The relaxation of the metastable state of the spin-crossover compound [Fe(L)(2)](ClO(4))(2).H(2)O, with L = 2,6-bis(pyrazol-1-ylmethyl)pyridine, populated by the LIESST (light induced excited spin state trapping) effect, has been investigated by magnetic measurements. The time dependence of the relaxation curve at several temperatures, starting from different initial states, is in the shape of stretched exponentials, and the thermal variation of the photostationary state under constant photoexcitation is progressive and reversible. These features are satisfactorily modeled by considering noninteracting two-level systems with a distribution of activation energies. A suggested origin for the distribution is the conformational flexibility of the nonplanar heterocyclic ligands. The effect of the intensity distribution during the LIESST process is also accounted for in a simple way. 相似文献
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Computational fluid dynamics, where simulations require largecomputation times, is one of the areas of application of highperformance computing. Schemes such as the SIMPLE (semi-implicitmethod for pressure-linked equations) algorithm are often usedto solve the discrete Navier-Stokes equations. Generally theseschemes take a short time per iteration but require a largenumber of iterations. For simple geometries (or coarser grids)the overall CPU time is small. However, for finer grids or morecomplex geometries the increase in the number of iterationsmay be a drawback and the decoupling of the differential equationsinvolved implies a slow convergence of rotationally dominatedproblems that can be very time consuming for realistic applications.So we analyze here another approach, DIRECTO, that solves theequations in a coupled way. With recent advances in hardwaretechnology and software design, it became possible to solvecoupled Navier-Stokes systems, which are more robust but implyincreasing computational requirements (both in terms of memoryand CPU time). Two approaches are described here (band blockLU factorization and preconditioned GMRES) for the linear solverrequired by the DIRECTO algorithm that solves the fluid flowequations as a coupled system. Comparisons of the effectivenessof incomplete factorization preconditioners applied to the GMRES(generalized minimum residual) method are shown. Some numericalresults are presented showing that it is possible to minimizeconsiderably the CPU time of the coupled approach so that itcan be faster than the decoupled one. 相似文献
10.
Rare earth element substituted bismuth ferrites (BiFeO3) are of enormous importance as magnetoelectric materials. The polycrystalline samples of Bi
x
La1−x
FeO3 (x=0, 0.2, 0.4, 0.6, 0.8) were prepared by solid-state reaction using standard ceramic method. The single-phase formation of
these compounds was confirmed by X-ray diffraction (XRD) studies. The samples with x=0, 0.2, 0.4, 0.6 are found to be orthorhombic while the sample with x=0.8 is triclinic. The dielectric constant (ε′) and dissipation factor (tan δ) were measured in the frequency range 100 Hz
to 1 MHz at room temperature and as a function of temperature at certain fixed frequencies (1 kHz, 10 kHz, 100 kHz, 1 MHz).
All the samples showed dielectric dispersion. The dielectric constant with temperature shows a broad peak; the peak temperature
shifts with frequency which reflects the relaxor-type behavior. The peak above 600 K in the measured temperature range corresponds
to antiferromagnetic ordering temperature (Néel temperature). The broadness of the peak changes with composition. The ac conductivity
as well as ε′ are found to be maximum for the sample x=0.2 at room temperature. 相似文献