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91.
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
92.
D. M. Upadhyay M. K. Shukla P. C. Mishra 《International journal of quantum chemistry》2001,81(1):90-104
Geometries of several clusters of water molecules including single minimum energy structures of n‐mers (n=1–5), several hexamers and two structures of each of heptamer to decamer derived from hexamer cage and hexamer prism were optimized. One structural form of each of 11‐mer and 12‐mer were also studied. The geometry optimization calculations were performed at the RHF/6‐311G* level for all the cases and at the MP2/6‐311++G** level for some selected cases. The optimized cluster geometries were used to calculate total energies of the clusters in gas phase employing the B3LYP density functional method and the 6‐311G* basis set. Frequency analysis was carried out in all the cases to ensure that the optimized geometries corresponded to total energy minima. Zero‐point and thermal free energy corrections were applied for comparison of energies of certain hexamers. The optimized cluster geometries were used to solvate the clusters in bulk water using the polarized continuum model (PCM) of the self‐consistent reaction field (SCRF) theory, the 6‐311G* basis set, and the B3LYP density functional method. For the cases for which MP2/6‐311++G** geometry optimization was performed, solvation calculations in water were also carried out using the B3LYP density functional method, the 6‐311++G** basis set, and the PCM model of SCRF theory, besides the corresponding gas‐phase calculations. It is found that the cage form of water hexamer cluster is most stable in gas phase among the different hexamers, which is in agreement with the earlier theoretical and experimental results. Further, use of a newly defined relative population index (RPI) in terms of successive total energy differences per water molecule for different cluster sizes suggests that stabilities of trimers, hexamers, and nonamers in gas phase and those of hexamers and nonamers in bulk water would be favored while those of pentamer and decamer in both the phases would be relatively disfavored. © 2001 John Wiley & Sons, Inc. Int J Quant Chem 81: 90–104, 2001 相似文献
93.
Nirogi RV Kandikere VN Shukla M Mudigonda K Maurya S Boosi R 《Rapid communications in mass spectrometry : RCM》2006,20(11):1695-1700
A simple, sensitive and rapid high-performance liquid chromatography/positive electrospray ionization tandem mass spectrometry method was developed and validated for the assay of clopidogrel in human plasma. Following liquid-liquid extraction, the analytes were separated using an isocratic mobile phase on a reversed-phase column and analyzed by mass spectrometry in the multiple reaction monitoring mode using the respective [M+H](+) ions, m/z 322/212 for clopidogrel and m/z 264/154 for the internal standard. The assay exhibited a linear dynamic range of 5-6000 pg/mL for clopidogrel in human plasma. The lower limit of quantification was 5 pg/mL with a relative standard deviation of less than 8%. Acceptable precision and accuracy were obtained for concentrations over the standard curve range. A run time of 2.5 min for each sample made it possible to analyze more than 400 human plasma samples per day. The validated method has been successfully used to analyze human plasma samples for application in pharmacokinetic, bioavailability or bioequivalence studies. 相似文献
94.
Srishti Shukla Dommati Anand Kumar Sanga Venkata Anusha 《Natural product research》2016,30(5):583-589
Effect of aqueous methanol extract of different colour sweet bell peppers (Capsicum annuum L.) on parameters of diabesity and carbonyl stress was analysed in vitro. Yellow pepper displayed significantly (p < 0.001) higher intestinal α-glucosidase inhibitory activity than green and red pepper. Porcine pancreatic lipase inhibitory activity was significantly (p < 0.01) high in yellow and red pepper than in green pepper. Green and red pepper inhibited vesperlysine-type advanced glycation end products (AGEs) more potently than yellow pepper; however, pentosidine-type AGEs were similarly inhibited by all three peppers. Yellow and red pepper inhibited lipid peroxidation more potently (p < 0.01) than green pepper. Total polyphenol content and free radicals scavenging activities in yellow and red bell peppers were higher than in green pepper. Total flavonoid content was high in green pepper than that present in yellow and red peppers. Green pepper displayed presence of proanthocyanins; however, oligomeric anthocyanins were detected in yellow and red peppers. 相似文献
95.
Recent laboratory experiments [Stenzel et al., Phys. Rev. Lett. 96, 095004 (2006)10.1103/PhysRevLett.96.095004] have demonstrated interesting phenomena of propagating nonlinear whistler structures (spheromaks) and stationary field-reversed configurations, whose magnetic fields exceed the ambient magnetic field strength. Our objective here is to present simulation studies for these nonlinear whistler structures based on the three-dimensional nonlinear electron magnetohydrodynamic equations. The robustness and longevity of the propagating whistler spheromaks found in the experiments are confirmed numerically. Varying the toroidal field of the spheromak in the initial conditions, we find that the polarity and the amplitude of the toroidal field determine the propagation direction and speed of the spheromak. Our simulation results are in excellent agreement with those observed in the laboratory experiments. 相似文献
96.
97.
Howell EE Shukla U Hicks SN Smiley RD Kuhn LA Zavodszky MI 《Journal of computer-aided molecular design》2001,15(11):1035-1052
R67 dihydrofolate reductase (DHFR) is a novel enzyme that confers resistance to the antibiotic trimethoprim. The crystal structure of R67 DHFR displays a toroidal structure with a central active-site pore. This homotetrameric protein exhibits 222 symmetry, with only a few residues from each chain contributing to the active site, so related sites must be used to bind both substrate (dihydrofolate) and cofactor (NADPH) in the productive R67 DHFR?NADPH?dihydrofolate complex. Whereas the site of folate binding has been partially resolved crystallographically, an interesting question remains: how can the highly symmetrical active site also bind and orient NADPH for catalysis? To model this ternary complex, we employed DOCK and SLIDE, two methods for docking flexible ligands into proteins using quite different algorithms. The bound pteridine ring of folate (Fol I) from the crystal structure of R67 DHFR was used as the basis for docking the nicotinamide-ribose-Pi (NMN) moiety of NADPH. NMN was positioned by both DOCK and SLIDE on the opposite side of the pore from Fol I, where it interacts with Fol I at the pore's center. Numerous residues serve dual roles in binding. For example, Gln 67 from both the B and D subunits has several contacts with the pteridine ring, while the same residue from the A and C subunits has several contacts with the nicotinamide ring. The residues involved in dual roles are generally amphipathic, allowing them to make both hydrophobic and hydrophilic contacts with the ligands. The result is a `hot spot' binding surface allowing the same residues to co-optimize the binding of two ligands, and orient them for catalysis. 相似文献
98.
An inhibition effect of PdCl2 on the rate of oxidation of sugars by alkaline hexacyanoferrate(III) has been observed. The order of reactions in hexacyanoferrate(III) and OH− is zero and unity, respectively, while that in sugars decreases from unity at higher sugar concentration. The kinetic data and spectrophotometric evidence support the formation of {PdII − (sugar)} and {PdII − sugar)2} complexes and their resistance to react with Fe(CN)63− © 1996 John Wiley & Sons, Inc. 相似文献
99.
The kinetics of the oxidation of oxalic acid by cerium(IV) in sulfuric acid medium has been studied voltammetrically. The specific reaction rate is 132±4.0 M–1s–1 at 25.0 °C. The energy of activation is 62.6±3.0 kJ mol–1. The entropy of activation is –2.7 J mol–1K–1. The specific reaction rate is influenced by complexation and also by ionic strength (). The most likely mechanism has been suggested.
(IV) . 132±4,0 M–1c–1 25,0 °C. 62,6±3,0 ·M–1. –2,7 ·K–1M–1. , (). .相似文献
100.
A micromethod for the determination of ascorbic acid has been developed. A 2–10 mg sample dissolved in glacial acetic acid is reacted with a known excess of bromine monochloride at ice-bath temperature, and the excess reagent is back-titrated iodometrically. The maximum deviation in the results is ± 1.5%. 相似文献