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91.
We have demonstrated the remarkable catalytic activity of silica nanoparticles (NPs) in the unusual bis-Michael addition of active methylene compounds to conjugated alkenes at room temperature. The catalyst silica NPs were reused up to seven runs without appreciable loss of catalytic activity. 相似文献
92.
High harmonic generation (HHG) in many-electron atoms is studied theoretically. The breakdown of the frozen-core single active electron approximation is demonstrated, as it predicts roughly the same radiation amplitude in all noble gases. This is in contradiction with experiments, where heavier noble gases are known to emit much stronger HHG radiation than lighter ones. This experimental behavior of the noble gases can be qualitatively reproduced when many-electron dynamics, within a simple approximation, is taken into account. 相似文献
93.
J. A. Ahmed S. B. Santra 《The European Physical Journal B - Condensed Matter and Complex Systems》2010,76(1):13-20
Lattice statistical models of equilibrium critical phenomena
generally obey finite size scaling (FSS) ansatz. However, the
critical behavior of the prototypical BTW sandpile model
demonstrating self-organized criticality at out of equilibrium is
described by a peculiar multiscaling behaviour. FSS hypothesis is
verified here on two versions (RSM1 and RSM2) of a rotational
sandpile model (RSM) with broken mirror symmetry. In these models,
sand grains flow only in the forward direction and in a specific
rotational direction from an active site after toppling. The
toppling rules are such that RSM1 will have less randomness whereas
RSM2 will have more randomness with respect to RSM. RSM1 is expected
to be more closer to BTW whereas RSM2 is expected to be more closer
to Manna’s stochastic model. Both RSM1 and RSM2 are found to belong
to the same universality class of RSM. The scaling functions of
RSM1 and RSM2 are also found to obey usual FSS hypothesis at out of
equilibrium instead of multiscaling as in BTW. 相似文献
94.
Chowdhury Budhadeb Mondal Monohar Hossain Barman Milan Krishna Saha Bidyut 《Research on Chemical Intermediates》2019,45(2):789-800
Research on Chemical Intermediates - In the present study the copper(III)-periodate (DPC) has been synthesized in an alkaline medium. The stability of this complex is significantly dependent on the... 相似文献
95.
S. Sinha S. B. Santra 《The European Physical Journal B - Condensed Matter and Complex Systems》2009,67(3):429-435
Unbiased random walks are performed on topologically biased anisotropic percolation clusters (APC). Topologically biased APCs
are generated using suitable anisotropic percolation models. New walk dimensions are found to characterize the anisotropic
behaviour of the unbiased random walk on the biased topology. Critical properties of electro and magneto conductivities are
characterized estimating respective dynamical critical exponents. A dynamical scaling theory relating dynamical and static
critical exponents has been developed. The dynamical critical exponents satisfy the scaling relations within error bar. 相似文献
96.
D. Patel S. Mukherjee N. Deshmukh J. Lubian Jian-Song Wang T. Correa B. K. Nayak Yan-Yun Yang Wei-Hu Ma D. C. Biswas Y. K. Gupta S. Santra E. T. Mirgule L. S. Danu N. L. Singh A. Saxena 《中国物理C(英文版)》2017,41(10):104001-104001
The effects of breakup reactions on elastic and α-production channels for the ~6Li+~(116)Sn system have been investigated at energies below and near the Coulomb barrier. The angular distributions of α-particle production differential cross sections have been obtained at several projectile energies between 22 and 40 MeV. The measured breakup α-particle differential cross sections and elastic scattering angular distributions have been compared with the predictions of continuum-discretized coupled channels(CDCC) calculations. The influence of breakup coupling has also been investigated by extracting dynamic polarization potentials(DPP) from the CDCC calculations. From the predictions of CDCC calculations the relative importance of the nuclear, Coulomb, and total breakup contributions have also been investigated. The nuclear breakup couplings are observed to play an important role in comparison to the Coulomb breakup for the direct breakup mechanisms associated in the reaction of ~6Li projectile with ~(116)Sn target nuclei. The influence of strong nuclear breakup coupling exhibits suppression in the Coulomb-nuclear interference peak. The direct breakup cross sections from the CDCC calculations under-predict the measured α-particle differential cross sections at all energies. This suggests that the measured α particles may also have contributions from other possible breakup reaction channels. 相似文献
97.
98.
Sachin B. Baravkar Mahendra A. Wagh Debasish Paul Manas Santra Gangadhar J. Sanjayan 《Tetrahedron letters》2018,59(38):3473-3476
Herein, we report synthesis and in vitro anticancer activity of conformationally constrained Smac mimetics containing reverse turn inducing motifs “Ant-Pro” and “sAnt-Pro”. The synthesis of Smac analogs with diverse hydrophobic groups at the C-terminus was carried out using solution phase peptide synthesis. The synthesis of Ant-Pro containing analogs 3a–j was carried out by ring opening of benzoxazinones 7a–c, whereas, their sulfonamide counterparts 4a–h were synthesized by using routine acid-amine coupling reaction. In vitro anticancer studies against breast cancer cell line MDA-MB-231 revealed that some of the new analogs had better anticancer activity than the standard AVPI Smac tetrapeptide. 相似文献
99.
The beam optics of the 6 MV folded tandem ion accelerator, that has recently been commissioned at Bhabha Atomic Research Centre,
Mumbai, is presented. Typical beam trajectories for proton and 12C beams under different conditions, are shown. The constraints on the design due to the use of the infrastructure of the Van
de Graaff accelerator, which existed earlier, are discussed. 相似文献
100.