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111.
112.
C. S. Singh S. N. Rai R. Srivastava D. K. Rai 《Zeitschrift für Physik A Hadrons and Nuclei》1984,319(1):9-11
Total cross-sections for electron impact excitation of 11 S – 23 S transition in helium have been calculated using variable-charge Coulomb-projected Born approximation and also using a distorted wave model in which the prior form of theT-matrix is used. The comparison of the two sets of results enables us to make certain observations about the suitability of the variable-charge Coulomb-projected Born approximation. 相似文献
113.
The effect of including distortion (with and without exchange) in the wavefunction for the continuum electron while calculating
the probability of autoionization of 2s
2
1
S. 2s2p
1,3
P, 2p
2
1
D and 2p
2
1
S states of He and Li+ has been studied. 相似文献
114.
Summary The pH of an aqueous solution of Gum Dhawa (Anogeissus latifoliaWall.) is 2.68 and it is sensitive to pH changes. The absence of the sulphate and the presence of a slight trace of phosphate, confirms the view that the acidity is due to the presence of carboxyl groups, which are formed by the hydrolysis of the gum. The hydrogen ion activity increases up to a concentration of 3% and beyond this point it attains a steady value. The sp. cond. is zero at the zero concentration and the relation between sp. cond. and up to 3% concentration is linear and afterwards it attains a steady value. It has been found by experimental observation that the gum solution has got no buffering capacity. Neutralization curves with NaOH and Ba(OH)2 show that the combination with alkali takes place in equivalent proportion. The viscosity of the gum solution always increases with increasing pH on the addition of HCl. The viscosity increase with NaOH is slow in the beginning, but after pH 4.2 it rises rapidly, attains a maximum and steeply falls off near pH 6.7. Now it decreases slowly and again a deviation is noted at 10.5. The viscosity is maximum near about the neutralization point. This is due to the stretched chain of the polymer unit. The fall in viscosity is explained by the folding chain theory in conjunction with mass action or common ion effect and due to the destruction of the proteins, by concentrated NaOH, which forms a complex with carbohydrate polymer.The authors wish to thank Dr.R. C. Mehrotra, Professor and the Head of the Chemistry Department, for providing all facilities for this work. Our thanks are also due to the Ministry of Education, Government of India, for the award of a research scholarship to one of us (V.K.S.). 相似文献
115.
Acta physica Academiae Scientiarum Hungaricae - A modified angular force model which takes into account the effect of electron-ion interaction on the basis ofSharma andJoshi model along with the... 相似文献
116.
The spectrum of theB 2Σ-X 2Σ system of the CaF molecule has been photographed in the second order of a 10.6 m concave grating spectrograph with 0.33 Å/mm dispersion. The rotational structure of the (0, 0) and (1, 0) bands has been analysed and the precise molecular constants have been obtained. Using the constants so determined the band origins of a large number of bands with 0 <v′,v″ < 10 have been calculated and used to obtain the accurate vibrational constants forB andX states and these are presented. 相似文献
117.
The solubility of hydrous UO2 in sodium hydroxide solutions containing sodium dithionite and/or Zn metal powder as reductants has been measured. The results provide no firm evidence for any amphoteric behavior of U(IV) but do set an upper limit of K ≤ 2 x 10?23 for the hypothetical reaction: The results provide no evidence for such a reaction. 相似文献
118.
Total cross-section for electron impact excitation of the resonance levels in Li, Na and K are calculated using the method
due to Crothers and McCarroll. The results are compared with other available theoretical and experimental data. 相似文献
119.
In the present paper, the general expressions for temperature distribution in an orthotropic plate of finite dimensions have been derived under the influence of an arbitrary volume heat source and arbitrary initial temperature distribution. The boundary conditions prescribed on the faces are of second kind. The solution is obtained by constructing an eigen value problem. The expression for unsteady temperature distribution consists of two parts—steady and pseudo-steady. The pseudo-steady parts of the solution have been obtained with the help of finite integral transform technique. The general expressions are further studied under different cases. The whole analysis is presented in the dimensionless form with the help of various dimensionless parameters,viz., F o , P o , K i , etc. 相似文献
120.
A magnetic domain wall (DW) injected and pinned at a notch in a permalloy nanowire is shown to exhibit four well-defined magnetic states, vortex and transverse, each with two chiralities. These states, imaged using magnetic force microscopy, are readily detected from their different resistance values arising from the anisotropic magnetoresistance effect. Whereas distinct depinning fields and critical depinning currents in the presence of magnetic fields are found, the critical depinning currents are surprisingly similar for all four DW states in low magnetic fields. We observe current-induced transformations between these DW states below the critical depinning current which may account for the similar depinning currents. 相似文献