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21.
22.
Charge distribution study in the alpha-particle induced fission of232Th+ effect of excitation energy
Ramaswami A. Srivastava B. K. Sahakundu S. M. Manohar S. B. Prakash Satya Ramaniah M. V. 《Journal of Radioanalytical and Nuclear Chemistry》1986,102(2):499-506
The fractional cumulative yields of135I,138Xe and140Ba in the particle (30 MeV) induced fission of232Th have been determined following the growth and decay of135gXe,138gCs and140La, respectively, employing high resolution gamma ray spectroscopy. The fractional cumulative yield values are 0.766±0.02, 0.813±0.03 and 0.991±0.004, respectively. The analysis of the data indicates a broader width of charge distribution () compared to the normally observed =0.56±0.06 for thermal neutron fission of235U. 相似文献
23.
Photocatalytic polypyrrole-TiO2-nanoparticles composite thin film generated at the air-water interface 总被引:1,自引:0,他引:1
Chowdhury D Paul A Chattopadhyay A 《Langmuir : the ACS journal of surfaces and colloids》2005,21(9):4123-4128
Herein, we report a new method of generation of TiO(2) nanoparticles (NPs) incorporated thin films of polypyrrole (PPy) at the air-water interface. Aqueous TiO(2) NPs when treated with H(2)O(2) and left in a chamber of pyrrole vapor resulted in the formation of a film at the interface, in addition to bulk precipitate. Spectroscopic, X-ray diffraction, and electron microscopic measurements establish the formation of a thin film of PPy with the incorporation of TiO(2) NPs. The TiO(2)-containing PPy films when transferred onto glass substrates were able to photo catalyze the decomposition of aqueous organic dyes: methyl orange and methylene blue. Further, these films could also photo catalyze the oxidation of iodide to triiodide ions in aqueous potassium iodide solution. We find that the PPy-TiO(2) composite films catalyze the reactions in the presence of light more efficiently than a suspension of TiO(2) NPs. 相似文献
24.
The compositions in the YBa2−xLaxCu3O7−δ (0x0.2) system were prepared by the solid state reaction, employing a novel high-temperature oxygen sintering route. The modified sintering route yields dense slab like microstructures with large grains. The decomposition (incongruent melting) temperature of the YBa2Cu3O7−δ (Y-123) phase was found to shift to higher temperatures with increasing oxygen partial pressure and lanthanum content. Structure remained orthorhombic up to x=0.2 with a decrease in the orthorhombic strain ((b−a)/b). Iodometric titration indicated a systematic increase in the oxygen content with increasing lanthanum content. Thermo-gravimetric studies in various oxygen partial pressures revealed that the oxygen diffusion in to the YBa2Cu3O7−δ (δ>0.5) lattice is an exothermic event and takes place at temperatures not less than 573 K. High-temperature thermal-expansion measurements in air indicated that the nonlinearity in thermal expansion behaviour was reduced by the substitution of lanthanum. 相似文献
25.
Om Prakash Ajay Kumar Richa Prakash Rosa M. Claramunt Ibon Alkorta José Elguero 《Tetrahedron》2005,61(27):6642-6651
Treatment of α,β-unsaturated carbonyl compounds, obtained by the reaction of DHA and aromatic (or heteroaromatic) aldehydes, with o-aminothiophenol results in the formation of 1,5-benzothiazepines and/or 1,4-benzothiazines depending upon the reaction conditions and structure of the aldehydes. The products were characterized by the combined use of multinuclear 1D and 2D NMR and GIAO/DFT calculations of 1H, 13C and 15N chemical shifts. The tautomerism of these compounds in solution was determined, they have an exocyclic CC double bond. 相似文献
26.
27.
Chandra Raju 《Czechoslovak Journal of Physics》1986,36(12):1350-1357
In this paper, we show that 2m
e
m
/(m
e
2
+m
2
= (g
V/g
A)
e
2
. From this expression, the Weinberg mixing parameter is shown to be 0·2254 or 0·2746. Assuming that the electron and muon neutrino masses are degenerate, we find thatm
v = (g
V/g
A)
e
2
. (m
e
m
)/M
WL, where MWL is the mass of the standard W± boson. The neutrino mass turns out to be 6·5 eV. The -neutrino mass is found to be about 81 MeV. The masses of c, t, s and b quarks are found to be respectively 1·7 GeV, 21·2 GeV, 0·57 GeV and 2·18 GeV by assumingm
d=m
u= 0·3 GeV. All these masses agree with other estimates except the b quark which has about half of its expected value. 相似文献
28.
R. S. Tomar Prakash Bhartia 《International Journal of Infrared and Millimeter Waves》1986,7(9):1281-1295
New design data for an open suspended microstripline is reported. Two most commonly used substrate materials, namely RT-Duroid (r=2.22) and fused quartz (r=3.78) are considered. Effects of dispersion and strip thickness are included in the results which are based on a fullwave spectral-domain analysis. The data, which is computed over the complete practical ranges of frequency and parameter values, is much more reliable than the currently available quasistatic results. 相似文献
29.
G.K. Surya Prakash 《Journal of fluorine chemistry》2002,117(2):103-105
1,3-Dehydroadamantane undergoes a facile reaction with tetrafluorohydrazine to give 1,3-bis(N,N-difluoroamino)adamantane, the product of 1,3-NF2 radical addition. 相似文献
30.
Summary The reversible complex formation between oxalatopentaammine cobalt(III), aluminium(III) and gallium(III) was investigated by the stopped flow technique at 30 ± 0.1 °C and I = 1.0 mol dm–3. The reactivity sequence: GaIII > AlIII is observed, however, the major path for gallium(III) was (NH3)5CoC2O4H2+ + GaOH2+ (NH3)5CoC2O4-Ga4+ + H2O. The formation and dissociation rate constants of the binuclear species have been compared with the analogous data for iron(III) and nickel(II) reported earlier. The results reflect the fact that the half-bonded exalato moiety of (NH3)5CoC2O
inf4
p+
acts as a chelating agent for the metal ions.Author to whom all correspondence should be directed. 相似文献