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51.
Manoj Kumar Anant Deshpande Chintan Gupta A. K. Biswas A. K. Nath 《Journal of Chemical Sciences》2002,114(6):659-673
Selective multi-photon dissociation (MPD) of Freon-22 (CF2HC1) molecules has been carried out using a TEA CO2 laser at various CO2 laser lines (9P(20)-9P(26)) in order to maximize the yield of C-13 isotope in the product (C2F4) at an enrichment factor of 100. The effects of laser pulse tail due to the presence of N2 in the laser mixture on the enrichment factor and yield of C-13 are investigated. It is found that the addition of a small
amount of N2 is possible in the laser mixture without a significant drop in the yield at desired enrichment factor. Addition of a small
amount of N2 improves the laser efficiency considerably. At a given pulse energy, a slight change in the near field intensity distribution
of a laser severely affects the selectivity of C-13 isotope. The computed far-field intensity distributions of the measured
near-field intensities show marked spatial variation in the focal spots that leads to a drop in selectivity. For macroscopic
production of C-13 isotope a simple and novel multi-pass cavity has been designed and tested to focus the energy repeatedly
keeping the optimum fluence constant at each focal spot. 相似文献
52.
Amit Deshpande Rahul Jain T. Kavitha Satyanarayana V. Lokam Jaikumar Radhakrishnan 《Random Structures and Algorithms》2005,27(3):358-378
An error‐correcting code is said to be locally decodable if a randomized algorithm can recover any single bit of a message by reading only a small number of symbols of a possibly corrupted encoding of the message. Katz and Trevisan 12 showed that any such code C : {0, 1}n → Σm with a decoding algorithm that makes at most q probes must satisfy m = Ω((n/log |Σ|)q/(q?1)). They assumed that the decoding algorithm is non‐adaptive, and left open the question of proving similar bounds for adaptive decoders. We show m = Ω((n/log |Σ|)q/(q?1)) without assuming that the decoder is nonadaptive. © 2005 Wiley Periodicals, Inc. Random Struct. Alg., 2005 相似文献
53.
J. ShankarV.K. Deshpande 《Physica B: Condensed Matter》2011,406(3):588-592
Glass samples with composition of (50−X)PbO-(25+X)TiO2-25B2O3 (where X=0, 5, 10 and 12.5 mol%) were prepared using conventional quenching technique. The glass transition temperature, Tg and crystallization temperature Tc were determined from the DTA. These glass samples were converted to glass ceramics by following two stage heat treatment schedule. The glass ceramic samples were characterized by XRD, SEM and dielectric constant measurements. The XRD results revealed the formation of ferroelectric lead titanate (PT) as a major crystalline phase in the glass ceramics. The density increases and the CTE decreases for all glass ceramics with increase in X (mol%). This may be attributed to increase in PT phase. The SEM results which show rounded crystallites of lead titanate, also supports other results. Hysteresis loops observed at room temperature confirms the ferroelectric nature of glass ceramics. The optimized glass ceramic sample exhibits high dielectric constant which is of technical importance. 相似文献
54.
55.
We study CP violation in a multi-Higgs doublet model based on aS
3×Z
3 horizontal symmetry. We consider two mechanisms for CP violation in this model: a) CP violation due to complex Yukawa couplings;
and b) CP violation due to scalarpseudoscalar mixings. We find that the predictions for ε′/ε, CP violation in B decays and
the electric dipole moments of neutron and electron are different between these two mechanisms. These predictions are also
dramatically different from the minimal Standard Model predictions. 相似文献
56.
S. Deshpande G. Hofstra R. A. Fletcher E. W. Abrahamson 《Photochemistry and photobiology》1991,54(3):485-488
Light scattering relaxation spectrophotometry has proven to be a useful technique to monitor rapid cytophysical changes in chloroplast suspensions brought about by flash illumination. This paper compares the Mg-ATP dependent light scattering behaviour of cholorplasts isolated from control and triazole-treated wheat seedlings. Our results suggest that triazole-treatment enhances Mg-ATP dependent activity. This same enhancement in control chloroplasts can be brought about by introducing potassium ion in the presence of valinomycin. Therefore, the potassium ion might account for part of the stress resistance conferred by triazole treatment. 相似文献
57.
V. K. Deshpande 《Ionics》2004,10(1-2):20-26
The electrical conductivity results of lithium borosilicate glasses with addition of Li2SO4 and LiCl have been critically analyzed. In general, it is observed that the factors viz. lithium fraction, fLi and the number of non-bridging oxygens (NBOs) govern the ionic conductivity in the lithium conducting glasses. For the same
fLi, the presence of mixed formers in the glass gives higher conductivity compared to that of the glass with only one former.
Thus the competitive network of glass in mixed former systems provides higher mobilities for lithium ions and hence high ionic
conductivity. The addition of Li2SO4 and LiCl in the lithium borosilicate glasses gave enhancement in the conductivity. However, the mechanism of enhancement
in conductivity is different in the two glass systems. The comparison of the result of binary, ternary and quaternary glass
systems suggests that in general, the decrease in activation energy, increase in fLi and increase in NBOs gives rise to enhancement in conductivity. For the same value of fLi the higher conductivity is exhibited by glasses with lower value of K (K=SiO2/B2O3).
Paper presented at the 2nd International Conference on Ionic Devices, Anna University, Chennai, India, Nov. 28–30, 2003. 相似文献
58.
Chuen‐Jinn Tsai Jyh‐Shyan Lin C. G. Deshpande Li‐Chun Liu 《Particle & Particle Systems Characterization》2005,22(5):293-298
An aerosol charge analyzer has been constructed to measure the charge distribution of NaCl particles generated in the laboratory. A radioactive electrostatic charge neutralizer utilizing Po‐210 was used to neutralize the electrostatic charge of the particles. The atomization technique was used to generate NaCl particles with diameters of 0.2 to 0.8 μm, while the evaporation and condensation method was adopted to generate particles of 0.01 to 0.2 μm in diameter. The experimental data demonstrates that the absolute average particle charge depends on the particle diameter, and is higher than that calculated by the Boltzmann charge equilibrium for particles within the range of 0.2 to 0.8 μm. The charge increases with decreasing NaCl concentration. When these particles are neutralized using the Po‐210 neutralizer, it is found that the electrostatic charge reaches the Boltzmann charge equilibrium. For 0.01 to 0.2 μm NaCl particles generated using the evaporation and condensation method, test results show that the absolute average particle charge is higher than that calculated by the Boltzmann charge equilibrium for particles larger than 0.03 to 0.05 μm in diameter, while it is lower than that predicted by the Fuchs theory [1], for particles smaller than 0.03 to 0.05 μm. However, after charge neutralization, particles with diameter above 0.05 μm reach the Boltzmann charge equilibrium condition, and the charges for particles with diameters of 0.010 to 0.05 μm, agree well with Fuchs' theory. 相似文献
59.
Z-scan studies on porphyrin derivative 总被引:2,自引:0,他引:2
K. Kandasamy K. Divakar Rao Rekha Deshpande P.N. Puntambekar Bhanu P. Singh Shankar J. Shetty T.S. Srivastava 《Applied physics. B, Lasers and optics》1997,64(4):479-484
Received: 10 January 1996 / Revised version: 15 June 1996 相似文献
60.
It has been shown in this paper that a test proposed by Barlow and Doksum (1972) based on the exponential scores statistic for testing exponentiality against increasing failure rate distributions is consistent for the much wider class of harmonic new better than used in expectation distributions. 相似文献