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991.
S. Lahiri Sh. Banerjee N. R. Das 《Journal of Radioanalytical and Nuclear Chemistry》1997,218(2):215-218
A radiochemical charged particle activation procedure has been developed for the production and separation of the carrier free radioisotopes,65Zn and66,67,68Ga. The carrier free radioisotopes produced by the irradiation of a pure copper foil with 50 MeV -particle beam through the nuclear reactions, (, pxn), (,pxn) and (,xn), have been quantitatively separated from the activated copper matrix from an aqueous hydrochloric acid and an alkaline solution using the liquid cation exchanger HDEHP, as an extractant. Detection of different radionuclides in the activated copper target and verification of their purity at different stages of their LLX separation have been performed by -ray spectrometric studies. 相似文献
992.
993.
T. Banerjee S. Chaudhuri M. Moore S. Ray P.S. Chatterjee P. Roychowdhury 《Journal of chemical crystallography》1999,29(12):1281-1286
Both 5-amino-1-(2-hydroxyethyl)imidazole-4-carboxamide (AHIC) and 5-amino-1-(2-chloroethyl)-4-cyanoimidazole (ACCI) have been synthesized and crystallized in the monoclinic space group P21/c, Z = 4, with a = 8.420(2), b = 9.759(2), c = 10.583(2) Å, = 111.80(2)° for AHIC and a = 6.139(1), b = 8.522(2), c = 15.156(3) Å, = 96.71(2)° for ACCI. Differences in the molecular geometries of the two compounds are attributed to the differences in the substituents at the 1- and 4-positions of the imidazole ring. The molecular conformation of AHIC is stabilized by intramolecular hydrogen bonding between the 5-amino and the vicinal carboxamide moiety, resulting in an extended planar structural pattern. The presence of the cyano group in the 4-position of ACCI prevents the formation of such an intramolecular hydrogen bond. Both the crystal structures are stabilized by networks of intermolecular hydrogen bonds. 相似文献
994.
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 letters》1993,71(10):1490-1493
995.
Sunanda Banerjee 《Pramana》1993,41(1):55-74
The four experiments, ALEPH, DELPHI, L3 and OPAL at LEP, have performed a large number of precise measurements to test Quantum Chromodynamics. The strong coupling constant has been measured with high precision:α s (Mz) = 0.123±0.004. The coupling constant has been found to be independent of quark flavour. The running ofα s has been demonstrated by the data. Second order QCD matrix element calculations have been tested from several measured distributions in 3-jet and 4-jet events. These distributions give evidence of the vector nature of the gluon and provide measurements of the QCD colour factors. The hadronic distributions are well reproduced by QCD Monte Carlo programs as well as by analytical calculations with soft gluon coherence effects. 相似文献
996.
997.
998.
Summary Molybdenum(V) and molybdenum(III) complexes [Mo2O3L4] and [Mo2L6] derived from hydroxamic acids (HL) were prepared and identified by Raman, i.r., e.s.r., electronic spectra and analytical data. The low magnetic moments of the dinuclear complexes are due to in part to intramolecular interactions. Electronic spectra and vibrational studies indicate the presence of a Mo2O3 core in the molybdenum(V) complexes. The relative intensities of the, main and satellite peaks in e.s.r. spectra indicate the dinulcear nature of molybdenum(III) hydroxamates. 相似文献
999.
A conversion of dimethylbenzo[d]suberone prepared from 5-chlorovaleric acid into butenolide, a precursor of tavacpallescencine, was described. 相似文献
1000.
Synthesis and Characterization of Nano-Crystalline Fluorine-Doped Tin Oxide Thin Films by Sol-Gel Method 总被引:1,自引:0,他引:1
A.N. Banerjee S. Kundoo P. Saha K.K. Chattopadhyay 《Journal of Sol-Gel Science and Technology》2003,28(1):105-110
Thin films of fluorine-doped tin-oxide (FTO) were prepared by sol-gel dip-coating technique. Stannous chloride (SnCl22H2O) and hydrogen fluoride (HF) were mixed with isopropyl alcohol to serve as source solution. X-ray diffraction (XRD) spectrum showed all the peaks of the crystalline SnO2. Analysis of XRD spectrum showed the particle size to be nearly 6 nm, which indicated the nanocrystalline structure of the films. Strain calculation by integral breadth (IB) method from XRD data showed a value of 0.010. UV-Visible spectrophotometric measurement showed high transparency of the films in the visible region and the band gap was calculated to be 3.34 eV. The room temperature resistivity of the films were of the order of 1 cm. Fluorine concentration in the films was determined from energy dispersive X-ray (EDX) study. Current-voltage (I-V) characteristics at high temperatures showed the Poole-Frenkel effect of thermionic emission. SEM study indicated the existence of fine grains in the film. FT-IR spectroscopy showed strong Sn—O and Sn—O—Sn bonding. 相似文献