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101.
It is shown that it is sufficient to solve a single first order differential equation to determine exact Bianchi type V imperfect fluid solutions of Einstein's field equations. Two exact solutions are presented in this paper. One of these two solutions corresponds to the case when the anisotropic pressure tensor is proportional to the shear tensor. This proportionality, it is shown, is a necessary but not a sufficient condition for the absence of heat flow in a Bianchi type V universe. It is also observed that the presence of heat flow necessarily introduces anisotropy in a Bianchi type V universe. 相似文献
102.
A simple spectrophotometric method for the determination of nylidrin hydrochloride, isoxsuprine hydrochloride and salbutamol sulphate is described, based on measurement of the orangeyellow species produced when the drugs are coupled with diazotized benzocaine (p-aminoethyl benzoate) in trimethylamine medium. The method is applicable over the range 1-12 mug ml for isoxsuprine hydrochloride and nylidrin hydrochloride and 1-8 mug ml for salbutamol sulphate. The method is a modification of the Bratton-Marshall reaction and is simple, reproducible, accurate and more sensitive than those cited in the literature. 相似文献
103.
A simple extractive photometric method for the determination of tetramisole hydrochloride in pharmaceutical preparations is described. The method uses the formation of coloured complexes of the drug with reagents such as Solochrome Dark Blue, Solochrome Black T, Bromocresol Purple, Bromothymol Blue, Bromophenol Blue and Bromocresol Green in an acidic buffer. The ion-pair complexes formed are quantitatively extracted into chloroform under the experimental conditions. 相似文献
104.
105.
A simple one dimensional diatomic chain model is proposed to explain the reflectivity spectra of TmTe as observed by Wardet al. It is suggested that the system undergoes a structural phase transition of order-disorder type at 4.2 K, where the new phase
assumes an anti-ferroelectric type of arrangement of the atoms. The results, we obtained, agree well qualitatively with the
experimental results. 相似文献
106.
Experiments with heavy ions at moderate energies show the importance of deformation in heavy ion collisions. A deformation
model which takes deformation dynamically into account is developed. Having described fusion and deep inelastic collision
for a very heavy system (Xe + Bi) and a medium heavy system (Ar + Th) at various energies successfully, we turn to some comparatively
lighter heavy ions where fusion is the most dominant feature. Fusion cross-sections for six pairs of lighter systems (35Cl +116Sn,58Ni+62Ni,35Cl+62Ni,32S+24Mg,24Mg+24Mg and12C+27Al) have been obtained using our deformation model which agree well with experiment. The two-slope-behaviour of fusion excitation
function which is an important feature of light ion fusion systematics is also obtained, in our model calculations for all
the systems studied. 相似文献
107.
The rates of peroxydisulphate oxidation of aromatic ketones have been found to be first order with respect to peroxydisulphate as well as of silver (I), but independent of the aromatic ketone. The effect of substituents on the rate of oxidation has been evaluated. The logk values have been plotted against the σ+ values, with ρ+=? 0.14. The reactivities of 1- and 2-acetyl naphthalene have been discussed. A mechanism of the oxidation of aromatic ketones based on reactive Ag+2 species has been suggested. 相似文献
108.
Nrusingha C. Khandual Kamala K. Satpathy P. L. Nayak 《Proceedings Mathematical Sciences》1972,76(3):129-135
The kinetics of oxidation of chalkone (phenyl styryl ketone) and cinnamaldehyde by T1 (III) acetate in aqueous acetic acid is of the first order in olefin and first order with respect to the oxidant. The parameters of the transition state theory have been computed. The rate of the reaction is strongly accelerated by increasing acid concentration. The reaction rate is also retarded by added sodium chloride and sodium acetate. The results have been interpreted in the light of the ionic mechanism considering T1 (OAc)3 to be the active oxidant in aqueous acetic acid. 相似文献
109.
110.