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21.
Abachi S Abbott B Abolins M Acharya BS Adam I Adams DL Adams M Ahn S Aihara H Alitti J Álvarez G Alves GA Amidi E Amos N Anderson EW Aronson SH Astur R Avery RE Baarmand MM Baden A Balamurali V Balderston J Baldin B Banerjee S Bantly J Bartlett JF Bazizi K Bendich J Beri SB Bertram I Bezzubov VA Bhat PC Bhatnagar V Bhattacharjee M Bischoff A Biswas N Blazey G Blessing S Bloom P Boehnlein A Bojko NI Borcherding F Borders J Boswell C Brandt A Brock R Bross A Buchholz D Burtovoi VS Butler JM 《Physical review letters》1996,77(25):5011-5015
22.
Abachi S Abbott B Abolins M Acharya BS Adam I Adams DL Adams M Ahn S Aihara H Alitti J Álvarez G Alves GA Amidi E Amos N Anderson EW Aronson SH Astur R Avery RE Baden A Balamurali V Balderston J Baldin B Bantly J Bartlett JF Bazizi K Bendich J Beri SB Bertram I Bezzubov VA Bhat PC Bhatnagar V Bhattacharjee M Bischoff A Biswas N Blazey G Blessing S Bloom P Boehnlein A Bojko NI Borcherding F Borders J Boswell C Brandt A Brock R Bross A Buchholz D Burtovoi VS Butler JM Carvalho W Casey D 《Physical review letters》1996,76(18):3271-3276
23.
Alexopoulos T Allen C Anderson EW Balamurali V Banerjee S Beery PD Bhat P Bishop JM Biswas NN Bujak A Carmony DD Carter T Choi Y Cole P DeBonte R DeCarlo V Erwin AR Findeisen C Goshaw AT Gutay LJ Hirsch AS Hojvat C Jennings JR Kenney VP Lindsey CS Loomis C LoSecco JM McMahon T McManus AP Morgan N Nelson K Oh SH Porile NT Reeves D Rimai A Robertson WJ Scharenberg RP Stampke SR Stringfellow BC Thompson M Turkot F Walker WD Wang CH Warchol J Wesson DK Zhan Y 《Physical review D: Particles and fields》1993,48(3):984-997
24.
Bankim C. Das I. Dey G. Biswas R. Banerjee Y. Iitaka A. Banerjee 《Journal of chemical crystallography》1993,23(6):509-512
The crystal structure of C6H16N8O2·CuCl2, a biguanide metal complex, has been determined by X-ray diffraction data using MoK radiation. The compound crystallizes in the monoclinic space groupP21/a, witha=11.074(4),b=12.061(4),c=5.312(3)Å and=102.8(1)°.The structure was solved by direct methods and refined by full-matrix least-squares to a finalR value 0.037 with 1245 unique reflections. The complex molecule is centrosymmetric, with the Cu atom (0.5,0.5,0.5) on a crystallographic center of symmetry. The complex molecule is rhombic planar with a trans configuration. 相似文献
25.
LetX be a compact Riemann surface andM s p (X) the moduli space of stable parabolic vector bundles with fixed rank, degree, rational weights and multiplicities. There is a natural Kähler metric onM s p (X). We obtain a natural metrized holomorphic line bundle onM s p (X) whose Chern form equalsmr times the Kähler form, wherem is the common denominator of the weights andr the rank. 相似文献
26.
27.
Satchidanand S. Biswas Achamkulangara Sethumadhavan Pappu S. Murty 《Mikrochimica acta》1991,103(1-2):71-77
Inductively coupled plasma atomic emission spectrometry (ICP-AES) was employed to determine Y, Sm, Eu, Gd, Dy, Ho and Er in high purity terbium oxide. Terbium oxide was dissolved in 0.5 mol/l HNO3 and nebulized into the plasma generated by a 56 MHz RF generator at 1.5 kW output power. Using a Jobin-Yvon 1-m Czenry-Turner high resolution, high dispersion scanning monochromator, lines mutually interference-free as well as free of interference from the matrix Tb were chosen for the seven analytes. A set of standards containing the analytes in the concentration range 0.01–1.0 gmg/ml with 1 mg/ml Tb was used for calibration. It was necessary to apply background correction to the gross analyte line intensities in order to obtain linear calibration plots for the analytes. 相似文献
28.
Decomposition of isopropanol (IPA) on V2O5, Li0.02V2O5, Na0.02V2O5, Na0.06V2O5, Li0.33V2O5, and Na0.33V2O5 has been studied in the temperature range 186–300°C. The first four catalysts (α-phase) show predominately dehydration, whereas the last two (β-phase) have comparable dehydration and dehydrogenation activity. Dehydration activity increases with alkali metal concentration within the α-phase, but falls sharply on the β-phase catalysts. This difference is attributed to the different rate determining steps for the reaction on the α- and β-phase catalysts. X-ray and ir spectral data show that the β-phase catalysts are much more stable than the α-phase. A mechanism for the dehydration of IPA based on the electrical resistivity, ESR spectra, and kinetic data has been proposed. 相似文献
29.
Mukul Biswas Madhusudan Banerjee Mrinal M. Maiti 《Journal of polymer science. Part A, Polymer chemistry》1985,23(10):2631-2646
Kinetics of polymerization of N-vinylcarbazole over Co(II)-13X molecular sieves in toluene have been studied. The rate of polymerization (Rp) has been found to be second order with respect to percent exchange level of Co(II) and also to the NVC concentration at all the reaction temperatures of 40, 50 and 60°C. The rate increases with decreasing pH of the original exchanging salt solution up to a pH of about 3.5, beyond which it falls. The overall activation energy of polymerization has been found to decrease with increase in monomer concentration, exchange level of Co(II), and the hydrogen ion concentration of the original exchange solution. Average degree of polymerization also follows a similar trend. A mechanism of polymerization involving simultaneous propagation on both metal ion Co(II) and proton on a zeolite surface has been suggested. The two propagation routes are characterized by an average activation energy of 10.36 kcal/mol and 5.40 kcal/mol on the metal ion and proton centers, respectively. 相似文献
30.
Biswas P Panja SS Manogaran S Chakraborty T 《The journal of physical chemistry. A》2005,109(14):3225-3234
Laser-induced fluorescence excitation and resolved fluorescence spectra following excitations of the single vibronic levels (SVL) of p-vinyltoluene (p-VT) and p-vinylfluorobenzene (p-VFB) have been measured in a seeded supersonic free-jet expansion. A complete vibronic assignment of the fluorescence spectrum measured following excitation of the 0(0)0-band of p-VT has been presented. Normal vibrational modes in the S0 and S1 states of the molecule have been calculated by CASSCF method, and the correlation between the two set of modes is made by expressing the excited-state normal modes in terms of those of the ground state. The calculations predict that in the excited state methyl and vinyl torsional motions of p-VT are extensively mixed with many of the out-of-plane modes of the aromatic ring. Our resolved fluorescence spectral data measured following SVL excitations essentially agree with such predictions. In the excited state, the molecule exhibits a dramatically low threshold for the rotor-induced IVR in a supersonic jet expansion. Several mechanisms have been discussed to explain the phenomenon. 相似文献