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1.
Proton and alpha particle spectra have been measured in the 12C+93Nb and 12C+58Ni reactions at E(12C)=40 and 50 MeV and in the 16O + 93Nb reaction at E(16O) =75 MeV. The spectra are compared with the statistical model calculations. The shapes of the calculated spectra are in
agreement with experimental data except for the alpha spectrum in the 12C + 93Nb reaction at 40 MeV. The observed evaporation bump is at ∼2 MeV lower energy compared to the calculated one. This discrepancy
could imply alpha particle emission from a deformed configuration before compound nucleus formation at this near Coulomb barrier
beam energy. 相似文献
2.
Treatment of 1H-4,5-dihydro-3-aryl-5-(2-hydroxyaryl)pyrazole with o-dibromoxylene under liquid-liquid phase transfer catalytic conditions using tetra-n-butylammonium hydrogen sulphate or [18]-crown-6 as PT catalyst, benzene/chloroform as organic phase and 50% aqueous potassium hydroxide as second phase, afforded novel 2,5,9,10-tetrahydro [7,8-g] benzo-8-arylpyrazolo[4,5-e] [1,5-b] benzoxazonines. 相似文献
3.
Multiple emulsions stabilized by colloidal microcrystalline cellulose (CMCC, Avicel RC591) at the w/o and o/w interfaces, and by the addition of Span 80 or Span 85 at the w/o interface, were studied by means of brightfield microscopy, freeze-etch electron microscopy, droplet size distribution analysis and rheologic measurements. Stable multiple emulsions were prepared by incorporation of sodium chloride in the innermost aqueous phase, thereby creating an osmotic gradient preventing loss of the inner aqueous phase to the external aqueous phase. Freeze-etch electron microscopy of the multiple emulsions indicated the presence of a network of microcrystalline cellulose at the outer o/w interface. It may be assumed that the surfactant directly stabilized the w/o interface by adsorption at the interface, as well as indirectly by facilitating wetting of the microcrystalline cellulose by the oil. From rheologic measurements, the existence of a three-dimensional network in the external aqueous phase was indicated by the considerable degrees of thlxotropy and significant static yield values of these multiple emulsions. 相似文献
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5.
A. T. Oza 《Crystal Research and Technology》1988,23(12):1517-1524
Strong colour bands are observed in the mull absorption spectra of the oxidized nickel chain dioximes bis (1,2-benzoquinonedioximato) Ni.I0.5 and bis (diphenylglyoximato) NiIIIBr in the long wavelength region of the optical spectrum which are ascribed to the reduced metal-metal distance due to oxidation. The uv-visible spectra of bis (dimethylglyoximato) NiII and bis (diphenylglyoximato) NiII have also been studied in the present comparative study. All the bands in the uv-visible range are assigned. The transitions and the effects of partial oxidation on the electronic transitions are discussed. 相似文献
6.
P. G. Oza H. S. Mazumdar A. K. Choudhary K. Gopalan 《Journal of Chemical Sciences》1984,93(2):189-193
A microcomputer system has been designed for semi-automatic operation of a solid source mass spectrometer used for geochronological
studies. It sequentially steps the magnetic field through pre-selected values, reads the digitized ion currents for a given
time and temporarily stores the data which can be transferred to a paper tape or directly to a desk top calculator for further
analysis. The unit is relatively inexpensive, made of readily available components and can be adapted to many laboratory automation
tasks 相似文献
7.
Cross sections for the ionization of hydrogen atoms by electron impact have been computed for incident energies from threshold up to 54 eV. A projection technique has been used in conjunction with a variational pseudostate calculation. 相似文献
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9.
P Meenakshi Raja Rao P Saraswathy G Krishnamurty R K Rout S K H Auluck Anurag Shyam I V Kulkarni Dipak H Oza 《Pramana》1989,32(5):627-639
Optical emission spectroscopic studies were carried out to characterise the plasma leading to the estimation of two plasma parameters, electron density and temperature. These experiments were conducted on a 2 kJ plasma device which is equipped with squirrel cage electrode configuration enclosed in a glass vacuum chamber filled with hydrogen at a pressure of 5 mbar. Spectral emissions obtained from each flash were photographed in the region of 4000–6000 Å using one metre Czerny-Turner spectrograph cum monochromator. Detailed examination of the observed features showed that theH β andH λ lines of hydrogen showed significant broadening of the order of 35 Å FWHM which is due to Stark effect expected in high density plasmas. Further several atomic lines of Cu and Zn from the electrode material (brass) showed broadening which was due to quadratic Stark effect. A comparative study of the broadening of lines obtained in DC arc, hollow cathode and plasma focus was made. Electron density from Stark broadened hydrogen lines and quadratic Stark Coefficient C4 for the CuI and ZnI lines were evaluated. The excitation temperature was determined from the line intensity ratio method using CuI lines. 相似文献
10.
Drug release from water-in oil-in water (w/o/w)multiple emulsions stabilized with colloidal microcrystal-line cellulose and various surface-active agents has been studied in vitro. Lidocaine hydrochloride and lidocaine base were used as model drugs for these studies. Drug concentrations were measured by HPLC, and effective diffusion coefficients were determined. 相似文献