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971.
The results of a Compton profile study on polycrystallineα-Mn are reported. Our measurement are compared with theoretical results computed for different 3d-4s electron configurations within the RFA model. Best agreement between the measured and calculated values is found for 3d
5·44s
1·6 configuration. Theoretical Compton profile ofγ-Mn calculated using the same procedure is close to that for bcc phase with similar electron configurations. 相似文献
972.
A simple, accurate and reliable titrimetric method is described for the determination of thiophanate-methyl, an important commercial fungicide. The method is based on its direct titration at room temperature with ammonium hexanitratocerate(IV) in sulphuric acid medium in the presence of potassium iodate as catalyst. The method permits detection of the end-point visually, potentiometrically or spectrophotometrically. The proposed method is recommended for routine determination of the fungicide in its commercial formulations. 相似文献
973.
974.
975.
The yield and energy distribution of long-range alpha-particles (lra) emitted from neutron-induced fission of235U have been measured at neutron energies; thermal, 125±12, 155±11, 185±10, 210±9, 240±9, 365±50 and 480±45 keV. The long-range
alpha-particles were detected in cellulose nitrate track detector foils. Results showed an increase of about 50% in the yield
at neutron energies in the region 150 keV≤E
n≤220 keV as compared to that of thermal neutrons. A calculation has been carried out to extract thelra to binary fission ratio forp-wave neutron induced fission. 相似文献
976.
977.
A covariance group suitable for describing ultrarelativistic kinematics is constructed through an Inönü-Wigner contraction of the Poincaré group. Eikonalization, helicity conservation and impact parameter representation arise as a consequence of our scheme. 相似文献
978.
Prasanna K. Mishra S. I. Hosain I. C. Goyal Anurag Sharma 《Optical and Quantum Electronics》1984,16(4):287-296
A scalar variational analysis for the fundamental mode of a graded-core, W-type fibre based on single and two parameter trial fields has been presented. Comparison with the exact numerical results shows that the two parameter trial field estimates the propagation characteristics accurately.On study leave from Physics Department, G.M. College, Sambalpur-768004, India. 相似文献
979.
The ratio of the mean square displacement of thermal vibration and the square of interatomic separation at the melting point has been calculated for several cubic metals using the frequency distribution derived from Bhatia's three-force constant model. It is found that this ratio has roughly the same value for metals of certain groups of the periodic table, but exhibits wide variation from one group to another. Lindemann's melting law is shown to be inadequate.We are grateful to the Council of Scientific and Industrial Research and to the University Grants Commission for financial assistance. 相似文献
980.
For a graph G, let ?(G) denote the maximum number k such that G contains a circuit with k diagonals.Theorem. For any graph G with minimum valency.If the equality holds and G is connected, then either G is isomorphic to Kn+1 or G is separable and each of its terminal blocks is isomorphic to Kn+1, or Kn+1 with one edge subdivided. 相似文献