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1.
2.
Summary If hydrogen is diffused electrolytically in a metal, it subsequently escapes out if the metal is left to itself. However this
hydrogen-treated metal does not totally regain the original magnitudes of its various physical properties,e. g., thermo e.m.f., electrical resistivity, elastic modulii etc. This effect has also been observed in the second-order elastic
effect (the Poynting effect) in nickel and two varieties of steel. Measurements were carried out first before hydrogen diffusion.
The samples were electrolytically diffused with hydrogen and the left to themselves for a few days and the measurements were
repeated. The changed values of the coefficient of Poynting effect are discussed in terms of the dislocations created by in-and
out-going hydrogen.
Now retired 相似文献
3.
The 57Fe Mössbauer technique has been used to investigate the effect of zinc oxide substitution in (25???x)MnO–xZnO–15Fe2O3–60B2O3 glass system (x?=?0, 5, 10, 15 and 20 mol% of ZnO ). Mössbauer absorption spectra for all the samples recorded at room temperature suggest the existence of the two paramagnetic quadrupole doublets. The observed variations in hyperfine parameters have been explained on the basis of cations distribution and exchange interaction at the lattice sites and it is concluded that B–B interaction increases while the metal–metal interaction decreases due to replacement of manganese oxide by zinc oxide. These results suggest that the present glass system exhibits a paramagnetic behaviour that changes towards the weak paramagnetic when manganese oxide was replaced with zinc oxide. 相似文献
4.
The collision-generated hybridization which has been found responsible for the on-site mixing of the atomic-likef-state and the band-liked states in mixed valence solids has been studied for the cerium solid. A practical expression which depends on the lattice
constant and temperature has been obtained for the collision-generated hybridization. Numerical calculations show that the
valence varies continuously with lattice constant and that temperature makes the transition smoother. The collision-generated
hybridization is found to be of significant strength in the intermediate valence regime; but over a wide range of the valence
near 3.5 it varies rather slowly without preferring a particular valence. Factors which can assist the collision-generated
hybridization in stabilizing the mixed valence phase at a particular lattice constant are discussed. 相似文献
5.
Cerium(IV) ammonium nitrate in substoichiometric amounts, promotes the intramolecular cyclization of epoxypropyl cinnamyl ethers to the corresponding 3,4,5-trisubstituted tetrahydropyran derivatives in moderate to good yields. 相似文献
6.
Adamovich MI Aggarwal MM Alexandrov YA Ameeva ZV Andreeva NP Anzon ZV Arora R Badyal SK Bhalla KB Bhasin A Bhatia VS Bubnov VI Burnett TH Cai X Chasnikov IY Chernova LP Chernyavski MM Dressel B Eligbaeva GZ Eremenko LE Friedlander EM Gadzhieva SI Gaitinov AS Ganssauge ER Garpman S Gerassimov SG Gill A Grote JG Gulamov KG Gulyamov UG Gupta VK Hackel S Heckman HH Haung H Judek B Kachroo S Kadyrov FG Kalyachkina GS Kanygina EK Kaul GL Kaur M Kharlamov SP Koss T Kumar V Lal P Larionova VG 《Physical review letters》1990,65(4):412-415
7.
Results are presented from a study of electrical breakdown of anodic aluminum oxide in a constant field with a platinum pressure electrode. Statistical breakdown parameters and their dependence on the magnitude and polarity of the applied voltage are obtained. Field and temperature dependences of breakdown delay time over the interval 10–6–103 sec are determined. It is shown that the experimental (E) curves can be rectified (in two segments) in the coordinates log E–1. This indicates a possible contribution to the breakdown mechanism by both tunnel injection of electrons from the cathode and subsequent avalanche multiplication of electrons within the dielectric.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 4, pp. 25–29, April, 1990.In conclusion, the authors thank T. V. Shmidt and E. Ya. Khanin for assistance in the study. 相似文献
8.
9.
R. K. Nigam B. P. Hajela S. Sengupta B. C. Srivastava K. M. Gupta 《Hyperfine Interactions》1986,28(1-4):935-939
The effect of pigments on the development of corrosion products between the painting system and metal surface when exposed to marine environments has been discussed. The pigments studied were; Red Mud Zinc chromate, Zinc chromate, Red oxide Zinc Phosphate, Manganese Phosphate Barium chromate and Basic Lead Silico Chromate. Mossbauer Spectroscopy revealed that the upper rust layer in all the cases consisted of-Fe203,-FeOOH and-FeOOH. The lower rust layer immediately in contact with the metal surface consisted of an asymmetrical doublet due to -FeOOH. 相似文献
10.