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1.
The nearside distribution of particles at intermediate transverse momentum, associated with a high momentum trigger hadron produced in a high energy heavy-ion collision, is broadened in rapidity compared with the jet cone. This broadened distribution is thought to contain the energy lost by the progenitor parton of the trigger hadron. We show that the broadening can be explained as the final-state deflection of the gluons radiated from the hard parton inside the medium by soft, transversely oriented, turbulent color fields that arise in the presence of plasma instabilities. The magnitude of the effect is found to grow with medium size and density and diminish with increasing energy of the associated hadron.  相似文献   
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We investigate and analyze the time-integrated nonlinear optical behaviour of an electronhole plasma in CdS as a function of the temperature and the exciting intensity. The competition between the temperature dependences of the absorption tail and of the manyparticle effects leads with increasing temperature around 160 K to a turn-over from a red- to a blue-shift of the absorption edge under excitation. The frequency dependence of the absorption for high plasma concentrations is in good agreement with theoretical calculations.  相似文献   
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Gobinda Majumder 《Pramana》2004,62(3):587-590
Semileptonic decays ofBX u lv have great importance both from theoretical and experimental point of view, as they are useful for extracting the magnitude ofV ub, one of the tiniest elements of CKM matrix. Similarly measurement ofB √ Ds×u can be used to calculateV ub The Belle Collaboration has measured these branching ratios and extractedV ub for various theoretical models.  相似文献   
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We have investigated the relations between microstructure and dielectric properties in order to fabricate sol-gel-derived highly (100) oriented Ba0.5Sr0.5TiO3 (BST 50/50) thin films with properties comparable to those of the bulk material. For the first time, we were able to fabricate BST thin films which exhibited the orthorhombic-to-tetragonal transition in addition to the commonly observed tetragonal-to-cubic transition. We were successful in explaining the commonly observed degradation of the dielectric behavior of BST thin films, when compared to that of the bulk material, in terms of grain size, compositional inhomogeneity (measured in terms of Sr/Ba ratio) between the grain bulk and grain boundary, and mechanical stresses. PACS 77.55.+f; 77.22Gm; 77.80.Bh; 77.80.Dj  相似文献   
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Employing 1-(2-methoxybenzyl)-2-(2-methoxyphenyl)-1H-benzimidazole (bpb) as a monodentate ligand, a new greenish-blue copper(II) complex, [Cu(bpb)2(NO3)2] (1a), has been synthesized. 1a has been characterized analytically and spectroscopically. The X-ray crystal structure of 1a reveals that it adopts a cis disposition with respect to the ligands. The solid state structure of 1a is stabilized by intramolecular offset face-to-face ππ stacking. Non-covalent supramolecular edge-to-face C–H?π interactions with neighboring molecules give 1-D supramolecular chains that further lead to the formation of an assembled 3-D supramolecular metal-organic framework via hydrogen bonding interactions. 1a shows blue fluorescence most likely due to intramolecular offset face-to-face ππ stacking. At room temperature, 1a is one-electron paramagnetic. It shows a rhombic EPR spectrum with g1 = 2.12, g2 = 2.42, and g3 = 2.52 in the solid state at liquid nitrogen temperature. In cyclic voltammetry, 1a displays a one-electron oxidative Cu(II)/Cu(III) couple. Our DFT calculations, corroborate the observed experimental results of 1a.  相似文献   
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We report, for the first time, a detailed crystallographic study of the supramolecular arrangement for a set of zinc(II) Schiff base complexes containing the ligand 2,6-bis((E)-((2-(dimethylamino)ethyl)imino)methyl)-4-R-phenol], where R=methyl/tert-butyl/chloro. The supramolecular study acts as a pre-screening tool for selecting the compartmental ligand R of the Schiff base for effective binding with a targeted protein, bovine serum albumin (BSA). The most stable hexagonal arrangement of the complex [Zn − Me] (R=Me) stabilises the ligand with the highest FMO energy gap (ΔE=4.22 eV) and lowest number of conformations during binding with BSA. In contrast, formation of unstable 3D columnar vertebra for [Zn − Cl] (R=Cl) tend to activate the system with lowest FMO gap (3.75 eV) with highest spontaneity factor in molecular docking. Molecular docking analyses reported in terms of 2D LigPlot+ identified site A, a cleft of domains IB, IIIA and IIIB, as the most probable protein binding site of BSA. Arg144, Glu424, Ser428, Ile455 and Lys114 form the most probable interactions irrespective of the type of compartmental ligands R of the Schiff base whereas Arg185, Glu519, His145, Ile522 act as the differentiating residues with ΔG=−7.3 kcal mol−1.  相似文献   
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A new orthohydroxy Schiff base, 7-ethylsalicylidenebenzylamine (ESBA) has been synthesised. The excited state intramolecular proton transfer (ESIPT) processes have been investigated by means of absorption, emission and nanosecond spectroscopy at room temperature and at 77 K in non polar solvents. The ESIPT is evidenced by a large Stokes shifted emission (11 000 cm−1) only at 77 K. From fluorescence and excitation spectra it is suggested that at least three different species are present in the excited state at room temperature. Our theoretical calculation at AM1 level confirm the cis-isomer to be the only viable form in the ground state.  相似文献   
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