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81.
G.A. Royce V.K. Mathur R.J. Abbundi M.D. Brown J.J. Fontanella M.C. Wintersgill 《Journal of luminescence》1984,29(2):205-213
A study was conducted of the effects of gamma radiation on samarium (Sm)-doped calcium flouride (CaF2) crystals. Optical absorption measurements indicate that many of the Sm3+ ions are converted to Sm2+ during irradiation. Heavy doses of 106 rad also modify the trapping structures and enhance certain defects within the crystals. A comparison is provided between unirradiated and heavily irradiated CaF2 crystals with three Sm concentrations: 0.01, 0.1, and 1.0 molar-percent. Thermoluminescence measurements indicate that the crystals with high Sm content provide less luminescence and that the activation energy is less than seen in the 0.01 molar-percent Sm crystals. 相似文献
82.
This paper discusses a class of nonlinear knapsack problems where the objective function is quadratic. The method is a branch and search procedure which includes an efficient algorithm to find the continuous (relaxed) solution and a reduction rule which computes tight lower and upper bounds on the integer variables. 相似文献
83.
The rotational excitation of the H2 and N2 molecules from (J→J+2,J=0) and (J→J+2,J=1) states by electron impact is studied, in the framework of the regional-plane-wave approximation. The empirical cut-off
parameterρ, involved in these calculations, is varied to give the best fit to the experimental data of Srivastava and co-workers. 相似文献
84.
H. Harde H. Burggraf H. W. K. Tom R. K. Jain P. B. Corkum R. S. Taylor Th. Sizer II J. D. Kafka C. Gable G. Mourou D. H. Auston P. R. Smith S. Williamson R. Trebino A. E. Siegman J. Kuhl J. H. Harris S. Sugai A. V. Nurmikko M. G. Li Veerendra K. Mathur Chi H. Lee M. Hasselbach S. C. Hsu H. S. Kwok 《Applied physics. B, Lasers and optics》1982,28(2-3):246-254
85.
86.
Let (X,τ) be a completely Hausdorff space. LetP be any topological property which is implied by complete regularity. Let (X,τ), be minimal-P. Then it has been shown that (X,τ), is completely regular and hence compact. 相似文献
87.
88.
A new diagram line corresponding to the electric quadrupole transition L2M3(β17) in the X-ray emission spectrum of erbium is reported at λ = 1658.25 X.U., using a 40 cm curved mica crystal spectrograph of transmission type. 相似文献
89.
R. K. Mishra K. Bhaumik S. C. Mathur S. Mitra 《International journal of quantum chemistry》1979,16(4):691-706
The problems connected with the transformations of energy in the living systems are reviewed. Possibility of Bose–Einstein condensation by input of radiant energy over a critical level is considered as a route for overcoming the barriers of activation energy under the conditions of a pump and a thermalizing environment. Molecular force fields constitute the pump. Under our scheme excitons constitute the major fraction of bosons to so condense. Instantaneous dipoles of London theory are then examined as excitons. Lastly an energy packet from a quantized dipolar field is suggested rather than the concept of “conformons.” Questions of charge and of other modes of energy transfer are briefly discussed. 相似文献
90.
R.M. Mehra P.C. Mathur A.K. Kathuria Radhey Shyam 《Journal of Physics and Chemistry of Solids》1978,39(3):295-298
D.C. conductivity measurements have been made as a function of temperature and external electric field on bulk amorphous selenium. A decrease in the activation energy with increase of electric field has been observed. This has been interpreted in terms of a mixed, thermally activated and trap limited conduction process. 相似文献