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481.
The invariant differential cross section for inclusive electron production in p+p collisions at [FORMULA: SEE TEXT] has been measured by the PHENIX experiment at the BNL Relativistic Heavy Ion Collider over the transverse momentum range 0.4相似文献   
482.
J/psi production in d + Au and p + p collisions at square root of S(NN) = 200 GeV has been measured by the PHENIX experiment at rapidities -2.2 < y < +2.4. The cross sections and nuclear dependence of J/psi production versus rapidity, transverse momentum, and centrality are obtained and compared to lower energy p + A results and to theoretical models. The observed nuclear dependence in d + Au collisions is found to be modest, suggesting that the absorption in the final state is weak and the shadowing of the gluon distributions is small and consistent with Dokshitzer-Gribov-Lipatov-Altarelli-Parisi-based parametrizations that fit deep-inelastic scattering and Drell-Yan data at lower energies.  相似文献   
483.
The dichloro[(-)-sparteine-N,N']copper(II) complex provides Henry adducts with high enantioselectivities (73-97% ee) in Henry reaction between nitromethane and various aldehydes.  相似文献   
484.
Effect of substitution of diamagnetic trivalent indium ions on the composition Mg0.2Mn0.5Ni0.3InxFe2−xO4 with x varying from 0.1 to 0.3 in steps of 0.1 using citrate precursor techniques has been investigated. Single-phase cubic spinel structure of these samples has been confirmed from X-ray diffraction analyses. Micro structural features were examined by TEM images. Lattice constant ‘a’ initially increases up to x = 0.1 and thereafter it decreases with further increase in x. This indicates that variation of ‘a’ with x do not obey Vegard's law. Nonlinear behavior of ‘a’ with x may be due to substitutional effect of larger In3+ ions (0.91Å) with smaller Fe3+ ions (0.67Å) in Mg-Mn-Ni ferrite. Ferrites have been investigated for their structural and magnetic properties such as variations in lattice constant, saturation magnetization, coercivity, retentivity, initial permeability, magnetic loss and relative loss factor (RLF). Fairly constant value of initial permeability over a wide frequency range (0.075–10 MHz) and low values of relative loss factor of order of 10−6–10−5 in same frequency range are main achievement of present investigations. RLF has been reduced by three orders of magnitude as compared to those samples prepared by conventional method. Low values of relative loss factor even at a high frequency indicate that prepared materials may have great potential for use in microwave devices. Possible mechanisms contributing to these properties have been discussed in this paper.  相似文献   
485.
We have identified the nuclei in the Te- and Xe-isotopic chains lying close to the critical point, through which the shape phase transition occurs, by using the sextic oscillator potential formalism. It has been found that 110Te, 124Te, and 124Xe isotopes are the most promising candidates for the critical-point nuclei slightly above the Z = 50 proton shell closure.  相似文献   
486.
Effective immobilization and delivery of genetic materials is at the forefront of biological and medical research directed toward tackling scientific challenges such as gene therapy and cancer treatment. Herein we present a biologically inspired hydrogen-bonded zinc adeninate framework (ZAF) consisting of zinc adeninate macrocycles that self-assemble into a 3D framework through adenine-adenine interactions. ZAF can efficiently immobilize DNAzyme with full protection against enzyme degradation and physiological conditions until it is successfully delivered into the nucleus. As compared to zeolitic imidazolate frameworks (ZIFs), ZAFs are twofold more biocompatible with a significant loading efficiency of 96 %. Overall, our design paves the way for expanding functional hydrogen-bonding-based systems as potential platforms for the loading and delivery of biologics.  相似文献   
487.
Herein, azadipeptidomimetic molecules were designed and synthesized using a quinoline-histidine-amino acid sequence with terminal amino acid modification. In-silico studies were carried out to evaluate the compound's HIV protease-1 inhibition temperament. In-vitro anti-proliferative possessions of the test compounds were studied by executing a series of experiments, namely DNA binding, bovine serum albumin (BSA) binding capability, and cytotoxicity assay on MCF-7 cells. The molecule 5j exhibited remarkable results in all experiments; it has an excellent DNA binding constant (3.76 × 105), higher serum albumin unbound concentration of 5.96%, and a significant antiproliferative effect on MCF-7 cells with IC50 value 0.31 nM.  相似文献   
488.
The cation-insertion solid state electrochemistry of a potassium copper(II) hexacyanoferrate in contact with LiClO4/DMSO, NaPF6/DMSO, and KPF6/DMSO electrolytes has been theoretically and experimentally studied using the voltammetry of immobilized particles methodology. Voltammetric data, combined with SEM/EDS analysis permit to determine a K0.876CuII1.328FeIII0.049[FeIII0.318FeII0.682(CN)6] stoichiometry for the synthesized solid. Separation of electronic and ionic contributions to Gibbs energy changes can be made based on cyclic voltammetric and open circuit potential measurements. These parameters can be combined to measure values of the Gibbs energy of cation-independent electron transfer of 7.2±0.4 (K+), 7.1±0.5 (Na+) kJ mol−1, in close agreement with the expected independence of this parameter on the electrolyte cation. The reduction Fe(III) centers bound to cyano groups exhibit a cation-dependent, essentially Nernstian character which can be described in terms of Na+ and K+ insertion/deinsertion while in the case of Li+ electrolytes there is significant co-cation diffusion. Chronoamperometric data provide estimates of the diffusion coefficients of Na+, and K+ ions through the solid around 10−9 cm2 s−1.  相似文献   
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