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81.
82.
J.-C. Alder F.W. Brasse W. Fehrenbach J. Gayler R. Haidan G. Glöe S.P. Goel V. Korbel W. Krechlok J. May M. Merkwitz R. Schmitz W. Wagner 《Nuclear Physics B》1975,91(3):386-398
We report on an experiment on electroproduction in the resonance region in the mass range 1505 ? W ? 1715 MeV. Data have been taken at q2 = 0. 22, 0.6 and 1 GeV2. The angular distributions obtained support that η production proceeds mainly through S-wave excitation due to the resonance S11(1535).The total cross section of the formation of this resonance decreases much more slowly with increasing momentum transfer than the total ep cross section. 相似文献
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84.
Iron(III) complexation with 2,3-pyridinediol has been investigated with a view to ascertaining the structures of the complexes formed and examining the analytical potential of this biochemically important ligand. 相似文献
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Selvakumar K Singh HB Goel N Singh UP Butcher RJ 《Dalton transactions (Cambridge, England : 2003)》2011,40(38):9858-9867
Synthesis and structural characterization of a new class of pincer type bicyclic diacyloxy- and diazaselenuranes is reported. The reaction of dimethyl 2-bromo-5-tert-butylisophthalate (28) with sodium benzeneselenolate affords the corresponding monoselenide, dimethyl 5-tert-butyl-2-(phenylselanyl)isophthalate (29). Reduction of 29 with LiAlH(4) provides 5-tert-butyl-2-(phenylselanyl)-1,3-phenylene)dimethanol 31. Oxidation of 29 or its hydrolyzed derivative, 5-tert-butyl-2-(phenylselanyl)isophthalic acid (30), with H(2)O(2) results in the formation of bicyclic diacyloxyselenurane (25). The reaction of 30 with aniline using the DCC coupling reaction gives 5-tert-butyl-N(1),N(3)-diphenyl-2-(phenylselanyl)isophthalamide (38). Reaction of 38 with H(2)O(2) leads to the formation of the corresponding bicyclic diazaselenurane (27) via selenoxide intermediate 39. Compounds 25, 27, 29 and 31 were characterized by single crystal X-ray crystallography. The structural aspects of the pincer type bicyclic chalcogenuranes are investigated using experimental and computational studies and compared with the related systems. 相似文献
88.
JPC – Journal of Planar Chromatography – Modern TLC - Dendrophthoe falcata (Linn. f.) Etting. is a stem parasite commonly known as ‘Vanda’ in the Ayurvedic system of... 相似文献
89.
Tina Chakrabarty Amaranadh Jasti N.K. Goel Vinod K. Shahi Sunil Sabharwal 《Radiation Physics and Chemistry》2011,80(7):803-809
Radiation-induced and thermal cross-linked sulfonated poly(ether sulfone) (SPS)–sulfonated poly(ether ether ketone) (SPK) composite ion-exchange membranes (SPS/SPK(γ) and SPS/SPK(T), respectively) were prepared. Their performances for water electrolysis were comparatively assessed. Thermal cross-linked membrane (SPS/SPK(T)) showed cross-linking of part functional groups (–SO3H) and thus deterioration in membrane conductivity. While, radiation-induced cross-linked membrane (SPS/SPK(γ)) avoided any cross-linking between functional groups and thus conductivity. Electrolysis performances of these membranes were evaluated in comparison with Nafion117 membrane. Relatively low current efficiency (CE) for SPS/SPK and SPS/SPK(T) membranes was due to their high mass transfer (water) via electro-osmotic drag, which was negligible for SPS/SPK(γ) membrane. SPS/SPK(γ) membrane exhibited comparable stabilities and water splitting performance with Nafion117 membrane, which revealed its suitability as substitute for electrochemical applications. 相似文献
90.
In this paper we carry out the performance analysis of traffic groomed multilayer optical networks. It is seen that the number of wavelength channels required decreases as the wavelength grooming factor increases. We have evaluated blocking probability for different load and grooming factor. The performance of the network has been evaluated for different conditions; first for fixed number of links with grooming factor set to 3 and subsequently with increase in grooming factor up to 18 in steps. The load on each link is selected as 2, 5, 9, 12, 15 and 20 Erlangs and the blocking probability as function of number of optical channels has been evaluated. In this work the effect of number of wavelength channels, traffic load and grooming factor on network blocking probability has been studied. The investigation reveals that the blocking probability decreases with increase in wavelength channels. Similarly we found that the blocking probability increases with increase in traffic load which is quite evident. Further it is shown that when the grooming factor is increased to significant value (16), the number of wavelengths requirement (8) becomes relatively stable. 相似文献