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41.
H. Huang B. P. Pathak R. Iafigliola L. Lessard J. K. P. Lee 《Zeitschrift für Physik A Hadrons and Nuclei》1977,282(3):285-292
The decay of mass separated90Rb has been studied usingβ,γ and conversion electron spectrometers in single and coincidence modes. The half-lives of the ground state and the isomeric level have been confirmed to be 162± 3 and 258±4 s, respectively. Theγ-rays from the decays of ground state and metastable state have been identified by measuring the decay of individual photopeaks using Ge(Li) detectors. The multipolarity of the 106.6 keV isomeric transition has been determined to beM3. Separate decay schemes of the ground and metastable states are presented. The levels of90Sr are discussed in terms of the available experimental and theoretical information. Radioactivity.90m,gRb [from238U(p, f)]; measuredT 1/2,E γ,I γ,γ—γ coin,I ce,cc,E β deduced logft,90Sr levels, mass separated90Rb. 相似文献
42.
Pathak Madhvesh Bohra Rakesh Mehrotra Ram C. Lorenz Ingo-Peter Piotrowski Holger 《Transition Metal Chemistry》2003,28(2):187-192
Reactions of cis-dialkoxy-bis(acetylacetonato)titanium(IV), [(acac)2Ti(OR)2] (R = Et, Pr
i
) with alkoxyalkanols (ROCH2CH2OH) (R = Me, Et, n-Bu) in 1:1 and 1:2 molar ratios in refluxing benzene under anhydrous conditions yield [(acac)2Ti(OR)2–n
(OCH2CH2OR)
n
] (n = 1 or 2) complexes, which were purified by distillation under reduced pressure. On the basis of i.r. and n.m.r. (1H- and 13C-) spectral studies, a cis-octahedral environment around TiIV is proposed. On keeping the distilled dark brown-red viscous liquid [(acac)2Ti(OEt)(OCH2CH2OBu)] for 2 weeks, orange yellow crystals of [(acac)2TiO]2 were obtained. A single crystal X-ray diffraction study suggests the product is a new modification of [(acac)2TiO]2. 相似文献
43.
Several novel glycofuranoses disaccharides related to mycobacterial cell wall polysaccharides were synthesized regio- and stereoselectively using 2,3,5-tri-O-benzoyl-alpha-D-arabinofuranosyl trichloroacetimidate as a glycosyl donor. 相似文献
44.
N. Pathak G. K. Mahanti T. K. Sinha Mahapatra 《International Journal of Infrared and Millimeter Waves》2007,28(11):953-960
In this paper, we present a new method based on real-coded Genetic Algorithm (GA) with elitist model for optimal design of
a reconfigurable symmetrical dual-beam uniformly spaced linear isotropic antenna array with phase-only control of quantized
phase shifters. The problem is to find a common amplitude distribution that will generate a pencil beam with zero phases and
a flat-top beam with discrete phases of a six-bit discrete phase shifter, without or with pre-fixing the value of dynamic
range ratio (|I
max/I
min|) of excitation current amplitude distribution equal to or less than five. 相似文献
45.
46.
47.
Chitra Shukla Anindita Banerjee Anirban Pathak 《International Journal of Theoretical Physics》2013,52(10):3790-3796
Recently bidirectional controlled perfect teleportation using 5-qubit states are reported in Int. J. Theor. Phys. (2013), doi:10.1007/s10773-013-1484-8 and ibid (2012), doi:10.1007/s10773-012-1208-5. In this paper we have shown that there exists a class of 5-qubit quantum states that can be used for bidirectional controlled teleportation. Two out of the three reported cases are the special cases of the proposed class of 5-qubit quantum states and one of them is not strictly a case of controlled bidirectional quantum teleportation. Further, we have shown that one can in principle, construct infinitely many 5-qubit quantum states for this purpose. We have also shown that the idea can be extended to bidirectional controlled probabilistic teleportation. Some potential applications of the proposed scheme and its modified versions are also discussed in relation with the implementation of quantum remote control and quantum cryptography. 相似文献
48.
The oxidation of 2,6-di-tert-butylphenol with tert-butylhydroperoxide (ButO2H) has been studied using polymer (XAD4) anchored salicylaldoxime, 1,3-propylene-bis-salicylaldimine and o-phenylene-bis-salicylaldimine complexes of molybdenum and vanadium in acetonitrile. The predominant products formed in the oxidation reactions were 2,6-di-tert-butylbenzoquinone (BQ) and 3,3′-5,5′-tetra-tert-butyldiphenoquinone (dPQ), whereas with some only 2,6-di-tert-butylbenzoquinone was formed. This is the first reported use of polymer anchored molybdenyl and vanadyl complexes in selective oxidation of 2,6-di-tert-butylphenol. Solvent plays an important role in this reaction. The effects of varying the ligand, metal and the support on the catalytic activity in the oxidation of 2,6-di-tert-butylphenol have been studied. With polymer anchored MoO2(salpen), 81% of 2,6-di-tert-butylbenzoquinone was formed from 2,6-di-tert-butylphenol. 相似文献
49.
Using quasi-steady-state and time-resolved high-field impedance techniques, the frequency-dependent dielectric permittivity of poly(vinylacetate) has been studied at electric field amplitudes as high as 400 kV/cm. The relative changes of the dielectric loss depend quadratically on the field amplitude and reach about 1 %. The magnitude and frequency-dependence of this non-linear dielectric effect and its time evolution after applying the high field are consistent with energy absorption from the field being at the source of the non-linear behavior. Based upon a phenomenological model of heterogeneous dynamics at isothermal conditions, the observed changes can be explained by locally increased configurational temperatures and the resulting accelerated dynamics. 相似文献
50.
V.V. Sreenivasu Mummidivarapu Rakesh Kumar Pathak Vijaya Kumar Hinge Jayaraman Dessingou 《Supramolecular chemistry》2014,26(7-8):538-546
A triethylene glycol di-imine locked triazole linked bis-calix[4]arene conjugate L has been synthesised and characterised. Conjugate L exhibits high fluorescence enhancement towards Zn2+ among the 13 metal ions studied down to a lower detection limit of ~12 ppb. The absorption and visual colour change experiments differentiated the Zn2+ from the other metal ions studied. The isolated zinc complex, [Zn2L] has been used as a chemo-sensing ensemble for the recognition of anions based on their binding affinities towards Zn2+. [Zn2L] was found to be sensitive and selective towards phosphate-bearing species and in particular to adenosine triphosphate (ATP2 ? ) among the other 20 anions studied as observed based on the changes occurred in the fluorescence intensity. The selectivity of the ATP2 ? has been shown on the basis of the changes observed in the emission and absorption spectral studies. The lowest detectable concentration for ATP2 ? with the chemo-sensing ensemble [Zn2L] is 348 ppb in methanol. The fluorescence quenching by the phosphate-based anions has been modelled by molecular mechanics studies and found that the anions possessing two or more phosphate moieties can only bridge between the two zinc centres, and hence those possessing only one phosphate moiety (H2PO4? and AMP2 ? ) are ineffective. 相似文献