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81.
We study a symmetric exclusion process in which the hopping rates at two chosen adjacent sites vary periodically in time and have a relative phase difference. This mimics a colloidal suspension subjected to external time-dependent modulation of the local chemical potential. The two special sites act as a classical pump by generating an oscillatory current with a nonzero dc value whose direction depends on the applied phase difference. We analyze various features in this model through simulations and obtain an expression for the dc current via a novel perturbative treatment. 相似文献
82.
Krishnamurty S Joshi K Zorriasatein S Kanhere DG 《The Journal of chemical physics》2007,127(5):054308
Recent experimental results have reported surprising variations in the shapes of the heat capacity curves and melting temperatures of gallium clusters in the size range of 30-55 atoms [G. A. Breaux et al., J. Am. Chem. Soc. 126, 8628 (2004)]. In the present work, we have carried out an extensive density functional investigation on ten selected clusters in the above mentioned size range. In particular, we have analyzed the ground state geometry and the nature of bonding in these clusters using electron localization function. We demonstrate that the existence or otherwise of a large island of atoms bonded with similar strength (i.e., the local order) in the ground state geometry is responsible for the variation in the shape of the heat capacity curve. We attribute the observed higher melting temperatures of some of the clusters (viz., Ga45-Ga48) to the presence of a distinct core and strong covalent bonds between the core and surface atoms. The present work clearly demonstrates that it is possible to understand the general trends observed in the heat capacity curves across the entire series on the basis of the analysis of their ground state. 相似文献
83.
Double stranded calf thymus deoxyribonucleic acid entrapped polypyrrole-polyvinyl sulphonate (dsCT-DNA-PPy-PVS) films fabricated onto indium-tin-oxide (ITO) coated glass plates have been used to detect organophosphates such as chlorpyrifos and malathion. These disposable dsCT-DNA-PPy-PVS/ITO bioelectrodes have been characterized using cyclic voltammetry, Fourier-transform-infra-red (FTIR) spectroscopy and atomic force microscopy (AFM), respectively. These biosensing electrodes have a response time of 30 s, are stable for about 5 months when stored in desiccated conditions at 25 °C and can be used to amperometrically detect chlorpyrifos (0.0016-0.025 ppm) and malathion (0.17-5.0), respectively. The additive effect of these pesticides on the amperometric response of the disposable dsCT-DNA-PPy-PVS/ITO bioelectrodes has also been investigated. 相似文献
84.
Sgarbi Ricardo Kumar Kavita Jaouen Frédéric Zitolo Andrea Ticianelli Edson A. Maillard Frédéric 《Journal of Solid State Electrochemistry》2021,25(1):45-56
Journal of Solid State Electrochemistry - M-N-C electrocatalysts (where M is Fe or Co) have been investigated for mitigating the dependence on noble metals when catalyzing the oxygen reduction... 相似文献
85.
Kannan R Rahing V Cutler C Pandrapragada R Katti KK Kattumuri V Robertson JD Casteel SJ Jurisson S Smith C Boote E Katti KV 《Journal of the American Chemical Society》2006,128(35):11342-11343
Nanocompatible chemistry which utilizes a novel nontoxic phosphino amino acid as a reducing agent has resulted in the development of therapeutically useful gold nanoparticles under biologically benign media. Stabilization of gold nanoparticles by the edible gum arabic matrix has provided an effective pathway toward in vivo stable target-specific gold nanoparticles. 相似文献
86.
A star edge-coloring of a graph is a proper edge coloring such that every 2-colored connected subgraph of is a path of length at most 3. For a graph , let the list star chromatic index of , , be the minimum such that for any -uniform list assignment for the set of edges, has a star edge-coloring from . Dvo?ák et al. (2013) asked whether the list star chromatic index of every subcubic graph is at most 7. In Kerdjoudj et al. (2017) we proved that it is at most 8. In this paper we consider graphs with any maximum degree, we proved that if the maximum average degree of a graph is less than (resp. 3), then (resp. ). 相似文献
87.
Himani Bhatt Kavita Chandwani Basanta Kumar Nandi Neha Kiritkumar Shah Susan Schandmand Raghava Varma 《Indian Journal of Physics》2010,84(12):1745-1750
The Wide Angle Shower Apparatus (WASA), previously operated at Uppsala, Sweden, is now installed at the COSY accelerator at
Jülich Forschungszentrum, Germany. The main goal of the WASA-at-COSY collaboration is to study symmetry violations in hadronic
reactions focusing on η and η′ decays. The Nuclear Physics Institute at Jülich Forschungszentrum and Department of Physics at IIT Bombay are collaborating
to understand QCD at intermediate distance scales using the proton beam from the COSY accelerator with proton and deuteron
targets. In this paper, we present the preliminary analysis on three different channels being investigated jointly by the
two groups. 相似文献
88.
We report a simple and compact implementation for single-pass second-harmonic-generation (SP-SHG) of cw laser radiation, based on a cascaded multicrystal (MC) scheme, that can provide the highest conversion efficiency at any given fundamental power. By deploying a suitable number of identical 30-mm-long MgO:sPPLT crystals in a cascade and a 30W cw Yb-fiber laser at 1064nm as the fundamental source, we demonstrate SP-SHG into the green with a conversion efficiency as high as 56% in the low-power as well as the high-power regime, providing 5.6W of green output for 10W and 13W of green output for 25.1W of input pump power. The MC scheme permits substantial increase in cw SP-SHG efficiency compared to the conventional single-crystal scheme without compromising performance with regard to power stability and beam quality. 相似文献
89.
Recent experimental reports bring out extreme size sensitivity in the heat capacities of gallium and aluminum clusters. In the present work we report results of our extensive ab initio molecular dynamical simulations on Ga30 and Ga31, the pair which has shown rather dramatic size sensitivity. We trace the origin of this size sensitive heat capacities to the relative order in their respective ground state geometries. Such an effect of nature of the ground state on the characteristics of heat capacity is also seen in case of small gallium and sodium clusters, indicating that the observed size sensitivity is a generic feature of small clusters. 相似文献
90.
Himatkumar V. Patel Kavita A. Vyas Sudhanshu P. Pandey Francis Tavares P. S. Fernandes 《合成通讯》2013,43(8-9):1021-1026
Various 5,6-disubstituted-2-phenyl-3(2H)-pyridazinones 4 have been synthesised by reacting triethyl phosphonoacetate anion with monophenylhydrazone of 1,2-dicarbonyl compounds 2. 相似文献