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111.
R. C. Barnà D. De Pasquale A. Italiano A. Trifirò M. Trimarchi C. Beck C. Bhattacharya F. Haas V. Rauch M. Rousseau O. Stezowsky A. Strazzeri 《Acta Physica Hungarica A》2002,16(1-4):281-289
The 132 MeV 16O + 58Ni reaction has been experimentally investigated by using coincident charged particle techniques. A closed-form theoretical approach, describing in a simple picture the non-equilibrium component and the evaporative one of the angular correlation between light particles and reaction residues emitted in a peripheral heavy-ion collision, is applied — in the hypotesis of a sequential process — to the (C,N,O)-α and (C,N,O)-p differential multiplicities for the 16O + 58Ni at 8.25 MeV/A deep inelastic collision. From this analysis some reaction mechanism information is deduced. 相似文献
112.
A spin-polarized vertical-cavity surface-emitting laser is demonstrated with electrical spin injection from an Fe/Al0.1Ga0.9As Schottky tunnel barrier. Laser operation with a spin-polarized current results in a maximum threshold current reduction of 11% and degree of circular polarization of 23% at 50 K. A cavity spin polarization of 16.8% is estimated from spin-dependent rate equation analysis of the observed threshold reduction. 相似文献
113.
114.
In this work, we completely characterize (1) permutation binomials of the form \(x^{{{2^n -1}\over {2^t-1}}+1}+ ax \in \mathbb {F}_{2^n}[x], n = 2^st, a \in \mathbb {F}_{2^{2t}}^{*}\), and (2) permutation trinomials of the form \(x^{2^s+1}+x^{2^{s-1}+1}+\alpha x \in \mathbb {F}_{2^t}[x]\), where s, t are positive integers. The first result, which was our primary motivation, is a consequence of the second result. The second result may be of independent interest. 相似文献
115.
Using a three- and four-dimensional Pauli–Villars regularization scheme, we investigate quark–antiquark and diquark condensation in the framework of the Nambu–Jona-Lasinio model. Using the particle Fermi momentum as a cutoff parameter, we study the energy gap width and coherence length for the meson condensate 〈\(q\bar q\)〉. We also study the energy gap width and critical coherence length (the distance over which there would be no diquark condensation) for the diquark 〈qq〉 and the dependence on the Fermi momentum. We obtain an estimate of the Fermi momentum value for meson and diquark condensates with an energy gap width of the order of 100 MeV. 相似文献
116.
The location of the plastic hinge axis in a three point SEN bend specimen is a highly controversial issue. An unambiguous and reliable estimation of rotational factor (rp) is very essential for the accurate determination of CTOD data. In contrast to the numerous studies reported on the rp determination in a cracked situation, limited information is available for a blunt notch situation, although many engineering structures do contain notchlike defects with finite root radius. An attempt is made to determine rp for two situations, namely well below the general yield and around the general yield. The work is based on a theoretical estimation of the plastic zone size using the stress concentration factor and the elastic as well as the elastic-plastic stress distribution. A theoretical estimation of rp in both the pseudo-elastic and the elastic-plastic situation is estimated through analytical modelling involving factors like plastic zone size, bend angle and notch opening displacement. The values of the rotational factor are found to increase from a small value to around 0.29 in a well below general yield situation to 0.53 to 0.54 in a general yield situation with continued loading. A wide discrepancy in the P/PGY ratio separating the two situations, i.e. well below general yield and around general yield, is observed. Consideration of the elastic and the elasto-plastic stress distribution indicates a much smaller value of P/PGY as compared to the ratio obtained from experimental load-displacement plots. 相似文献
117.
Shape‐memory behavior is the ability of certain materials to recover, on heating, apparently plastic deformation sustained
below a critical temperature. Some materials have good shape‐memory behavior as single crystals but little or none as polycrystals,
while others have good shape‐memory behavior even as polycrystals. We propose a method for explaining the difference.
Our approach is based on elastic energy minimization. It leads to a special class of nonlinear homogenization problems, involving
integrands that are degenerate near the origin. We explore the behavior of these problems through various examples and bounds.
The elementary “Taylor bound” and the newer “translation method” are central to our analysis.
Accepted October 26, 1995 相似文献
118.
Manne Naga RajuNeelam Uday Kumar Baddam Sudhakar ReddyNaredla Anitha Gangula SrinivasApurba Bhattacharya Kagga MukkantiNaveenkumar Kolla Rakeshwar Bandichhor 《Tetrahedron letters》2011,52(42):5464-5466
An alternative and scalable synthesis of dexlansoprazole ((R)-(+)-1); the (R)-enantiomer of Lansoprazole with an enantiomeric excess of >99.8% is presented. 相似文献
119.
Mukherjee S Dan A Bhattacharya SC Panda AK Moulik SP 《Langmuir : the ACS journal of surfaces and colloids》2011,27(9):5222-5233
The physicochemistry of interaction of the cationic polymer poly(diallyldimethylammonium chloride) (PDADMAC) with the anionic surfactants sodium dodecyl sulfate, sodium dodecylbenzenesulfonate, and sodium N-dodecanoylsarcosinate was studied in detail using tensiometry, turbidimetry, calorimetry, viscometry, dynamic light scattering (DLS), and scanning electron microscopy (SEM). Fair interaction initially formed induced small micelles of the surfactants and later on produced free normal micelles in solution. The interaction process yielded coacervates that initially grew by aggregation in the aqueous medium and disintegrated into smaller species at higher surfactant concentration. The phenomena observed were affected by the presence of isopropyl alcohol (IP) in the medium. The hydrodynamic sizes of the dispersed polymer and its surfactant-interacted species were determined by DLS measurements. The surface morphologies of the solvent-removed PDADMAC and its surfactant-interacted complexes from water and IP-water media were examined by the SEM technique. The morphologies witnessed different patterns depending on the composition and the solvent environment. The head groups of the dodecyl chain containing surfactants made differences in the interaction process. 相似文献
120.
Indra Sandal Amita Bhattacharya Uksha Saini Devinder Kaur Shveta Sharma Ashu Gulati Jonnala K Kumar Neeraj Kumar Jyotsna Dayma Pralay Das Bikram Singh Paramvir S Ahuja 《BMC chemical biology》2011,11(1):1-13