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91.
A study of optogalvanic (OG) signals in a uranium hollow cathode discharge using a tunable pulsed dye laser with intensities above saturation revealed certain systematic trends. The peaks of OG signals, for a given hollow cathode current, due to all transitions involving the ground state are within a certain range of values. The same is true of the OG signals due to transitions involving the 620 cm-1 and 3800 cm-1 lower metastable levels. For all transitions involving the same lower state, the peaks of OG signal vary linearly with the discharge current. The slopes of such straight lines are different for transitions involving different lower levels of uranium. Effects of radiation trapping are seen in the OG signals due to transitions involving the ground state of uranium at currents above 60 mA. Details of our observations are presented and discussed. 相似文献
92.
93.
K. L. Kapoor 《International journal of quantum chemistry》1973,7(1):27-34
SCF -LCAO -MO -CI calculations made on 2- and 4-amino-, and 2,4-diaminopteridines indicate that the most favorable site where the protonation can take place is N-1. 相似文献
94.
95.
Several characteristics of fission accompanied by long range alpha particles (LRA) have been studied in the thermal neutron
induced fission of235U. The kinetic energies of fission fragments and the LRA were measured with a back-to-back ionization chamber and semiconductor
detectors respectively. The kinetic energies of the two fragments and the LRA in LRA fission, along with the energies of pair
fragments in the normal binary fissions, were recorded event by event on a magnetic tape by means of a four-parameter data
acquisition system. The data were analysed to study the dependence of different quantities in LRA fission on the fragment
mass ratio, LRA energy and the total kinetic energy of the fission fragments. It is seen that the most probable energy of
LRA increases significantly for near symmetric mass divisions. The total kinetic energy for all mass ratios in LRA fission
is found to be (2.6±0.7) MeV larger than that in binary fission. The difference in the total kinetic energies in LRA and binary
fissions is seen to be dependent on mass ratio. This result may suggest that the scission configuration in LRA fission is
different for different mass ratios. Correlations between the fission fragment and LRA energies have been studied for several
mass ratios. It is seen that the most probable fragment kinetic energyĒ
k varies nearly linearly with the LRA energyE
a for various mass divisions but the variation of the most probable LRA energyĒ
a with fragment kinetic energyE
k is found to deviate from linearity for several mass ratios. From a least square fit to the variation ofĒ
k withE
a it is found that the slope (dĒ
k/dEa) increases with the increase in mass ratio. The present results are discussed to arrive at a better understanding of the
scission configuration in the fission accompanied by LRA emission. 相似文献
96.
97.
White organic light emitting diodes based on DCM dye sandwiched in 2-methyl-8-hydroxyquinolinolatolithium 总被引:1,自引:0,他引:1
Amit Kumar Ritu Srivastava Sukhwant S. Bawa Kapoor Singh Ishwar Singh 《Journal of luminescence》2010,130(8):1516-1520
Stable white electroluminescence (EL) has been achieved from organic LED, in which an ultrathin 4-(dicyanomethylene)-2-methyl-6-(p-dimethyl-aminostyryl)-4H-pyran (DCM) dye layer has been inserted in between two 2-methyl-8-hydroxyquinolinolatolithium [LiMeq] emitter layer and by optimizing the position of the DCM dye layer from the α-NPD/LiMeq interface. Electroluminescence spectra, current-voltage-luminescence (I-V-L) characteristics of the devices have been studied by changing the position of the dye layer. As the distance of DCM layer from α-NPD/LiMeq interface is increased, the intensity of host emission enhances rapidly. Introduction of thin layer of DCM in emissive layer increases the turn on voltage. The best Commission International de L’ Eclairage (CIE) coordinates i.e. (0.32, 0.33) were obtained with device structure ITO/α-NPD(30 nm) /LiMeq(10 nm)/DCM(1 nm)/LiMeq(25 nm)/BCP(6 nm)/Alq3(28 nm)/LiF(1 nm)/Al(100 nm). The EL spectrum covers the whole visible spectra range 400-700 nm. The color rendering index (CRI) for our best white light (Device 4) is 47.4. The device shows very good color stability in terms of CIE coordinates with voltages. The maximum luminescence 1240 cd/m−2 has been achieved at 19 V. 相似文献
98.
Vishaal Kapoor 《Journal of Number Theory》2010,130(3):534-538
Let {a1,a2,a3,…} be an unbounded sequence of positive integers with an+1/an approaching α as n→∞, and let β>max(α,2). We show that for all sufficiently large x?0, if A⊂[0,x] is a set of nonnegative integers containing 0 and satisfying
99.
In this paper global asymptotic stability and asymptotic behaviour of solutions of nonlinear delay difference equations has been studied and a few sets of sufficient conditions for global asymptotic stability are derived. 相似文献
100.
Pradnya Nalawade Sergej Naumov Sudhir Kapoor 《Journal of Physical Organic Chemistry》2013,26(11):870-878
The bimolecular electron transfer from p‐amino benzhydrazide (PABH) and its meta‐derivative (m‐amino benzhydrazide (MABH)) to specific one‐electron oxidant results in the formation of anilino radical. In case of PABH, reaction with ?OH radicals results in the synchronous formation of adduct as well as anilino radical. The interesting observation is that the yield of the anilino radical increases with increase in pH. The effect of substitution also has a significant effect on the formation of adduct. In case of MABH, significant yield of anilino radical gets form on reaction with ?OH radical. The free radical electron transfer from PABH and MABH to parent radical cation of non‐polar solvent also results in the formation of anilino radical only suggesting that the radical cation of PABH and MABH has short life time. The above results were supported by quantum chemical calculations. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献