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1.
Ajit Kumar Singh Seulgi Ji Baghendra Singh Chittaranjan Das Heechae Choi Prashanth W. Menezes Arindam Indra 《Materials Today Chemistry》2022
Herein, we report a Mott-Schottky catalyst by entrapping cobalt nanoparticles inside the N-doped graphene shell (Co@NC). The Co@NC delivered excellent oxygen evolution activity with an overpotential of merely 248 mV at a current density of 10 mA cm–2 with promising long-term stability. The importance of Co encapsulated in NC has further been demonstrated by synthesizing Co nanoparticles without NC shell. The synergy between the hexagonal close-packed (hcp) and face-centered cubic (fcc) Co plays a major role to improve the OER activity, whereas the NC shell optimizes the electronic structure, improves the electron conductivity, and offers a large number of active sites in Co@NC. The density functional theory calculations have revealed that the hcp Co has a dominant role in the surface reaction of electrocatalytic oxygen evolution, whereas the fcc phase induces the built-in electric field at the interfaces with N-doped graphene to accelerate the H+ ion transport. 相似文献
2.
Journal of Algebraic Combinatorics - The symbolic powers, in general, are not equal to the ordinary powers. Therefore, one interesting question here is for what classes of ideals ordinary and... 相似文献
3.
4.
Seperation of few carrier-free daughter isotopes from their respective parents, e.g.,132I from132Te,140La from140Ba and234Th from238U, using Adogen-464, a high molecular weight quaternary ammoaium salt by reversed phase extraction chromatographic technique is reported. 相似文献
5.
A. Banerjee S. B. Dutta Choudhury S. Chatterjee 《General Relativity and Gravitation》1992,24(9):991-999
It is shown that in the case of a spherical nonstatic fluid distribution undergoing shear-free motion the field equations in higher dimensional space-time can be reduced to a single second-order differential equation involving an arbitrary function of the radial co-ordinate. This result extends to higher dimensions a similar one obtained by Wyman and Faulkes earlier for 4D space-time. Solving this differential equation a number of new solutions is found, and the dynamical behaviour of one of the models is briefly discussed. The ansatz is later generalised to include the electromagnetic field as well. 相似文献
6.
G. K. Dalapati S. Chatterjee S. K. Samanta C. K. Maiti 《Applied Surface Science》2003,210(3-4):249-254
Thin films of titanium dioxide have been deposited on strained Si0.82Ge0.18 epitaxial layers using titanium tetrakis-isopropoxide [TTIP, Ti(O-i-C3H7)4] and oxygen by microwave plasma enhanced chemical vapor deposition (PECVD). The films have been characterized by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR). Dielectric constant, equivalent oxide thickness (EOT), interface state density (Dit), fixed oxide charge density (Qf/q) and flat-band voltage (VFB) of as-deposited films were found to be 13.2, 40.6 Å, 6×1011 eV−1 cm−2, 3.1×1011 cm−2 and −1.4 V, respectively. The capacitance–voltage (C–V), current–voltage (I–V) characteristics and charge trapping behavior of the films under constant current stressing exhibit an excellent interface quality and high dielectric reliability making the films suitable for microelectronic applications. 相似文献
7.
We have studied isospin symmetry violation in nuclear reactions by measuring simultaneously the cross-section of the following
two reactionsp +d →3H π+ andp +d →3He π0. The experiment was perfomed at the cooler synchrotron accelerator COSY, Jülich at several beam energies close to the correspondingη production threshold. We also have ongoing programmes onη-nucleus final-state interaction studies viap+6 Li →7 Be +η reactions, high resolution search for dibaryonic resonances and lambda-proton final state interaction studies. The experimental
details and results obtained so far are presented here 相似文献
8.
Dipak Ghosh Madhumita Lahiri Argha Deb Susobhan Das Krishnadas Purkait Biswanath Biswas Jayanta Roy Choudhury Rini Chatterjee Abdul Kayum Jafry 《Zeitschrift fur Physik C Particles and Fields》1996,71(1):243-249
The scaled factorial moments and the multifractal moments have been investigated in differentη-intervals to study the dynamical fluctuation of pions produced in 200 AGeV32S-Ag/Br interaction. In order to investigate the detail characteristics of intermittency behaviour, theF-moments are extracted up to the eighth order of moments in differentM-intervals. The analysis indicates a non-thermal phase transition and different regime of particle production during the hadronisation process. 相似文献
9.
J.M. Chatterjee S. Basu-Roy S.S. Ghugre S. Chattopadhyay R.P. Singh G.O. Rodrigues R.K. Chattopadhyay R.K. Bhowmik 《The European Physical Journal A - Hadrons and Nuclei》1998,1(1):55-59
A search for new isomers of nanosecond lifetimes were carried out in 153Eu via the 150Nd(7Li,xnγ) reaction. The single particle angular momentum alignment and dynamical moment of inertia estimated from the experimental
data indicate a configuration change at rotational energy ħω∼ 0.30 MeV. A decrease of B(E2) values is also observed at the
same frequency. An isomeric level is identified at an excitation energy of 3100 keV (Jπ=35/2−) which corresponds to this frequency. The lifetime of the level is found to be 8.6 ± 1.3 nanosecond.
Received: 22 April 1997 / Revised version: 26 September 1997 相似文献
10.
In this paper we report some of the important results of experimental investigations of the flicker noise near the metal-insulator
(MI) transition in doped silicon single crystals. This is the first comprehensive work to study low-frequency noise in heavily
doped Si over an extensive temperature range (2 K<T<500 K). The measurements of conductance fluctuations (flicker noise) were carried out in the frequency range 10−2<f<4 × 101 Hz in single crystalline Si across the MI transition by doping with phosphorous and boron. The magnitude of noise in heavily
doped Si is much larger than that seen in lightly doped Si over the whole temperature range. The extensive temperature range
covered allowed us to detect two distinct noise mechanisms. At low temperatures (T<100 K) universal conductance fluctuations (UCF) dominate and the spectral dependence of the noise is determined by dephasing
the electron from defects with two-levels (TLS). At higher temperatures (T>200 K) the noise arises from activated defect dynamics. As the MI transition is approached, the 1/f spectral power, typical of the metallic regime, gets modified by the presence of discrete Lorentzians which arise from generation-recombination
process which is the characteristic of a semiconductor. 相似文献