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41.
Abelev BI Aggarwal MM Ahammed Z Anderson BD Arkhipkin D Averichev GS Bai Y Balewski J Barannikova O Barnby LS Baudot J Baumgart S Belaga VV Bellingeri-Laurikainen A Bellwied R Benedosso F Betts RR Bhardwaj S Bhasin A Bhati AK Bichsel H Bielcik J Bielcikova J Bland LC Blyth SL Bombara M Bonner BE Botje M Bouchet J Brandin AV Bravar A Burton TP Bystersky M Cadman RV Cai XZ Caines H Calderón de la Barca Sánchez M Callner J Catu O Cebra D Chajecki Z Chaloupka P Chattopadhyay S Chen HF Chen JH 《Physical review letters》2007,99(11):112301
We present first measurements of the phi-meson elliptic flow (v2(pT)) and high-statistics pT distributions for different centralities from radical sNN=200 GeV Au+Au collisions at RHIC. In minimum bias collisions the v2 of the phi meson is consistent with the trend observed for mesons. The ratio of the yields of the Omega to those of the phi as a function of transverse momentum is consistent with a model based on the recombination of thermal s quarks up to pT approximately 4 GeV/c, but disagrees at higher momenta. The nuclear modification factor (R CP) of phi follows the trend observed in the K S 0 mesons rather than in Lambda baryons, supporting baryon-meson scaling. These data are consistent with phi mesons in central Au+Au collisions being created via coalescence of thermalized s quarks and the formation of a hot and dense matter with partonic collectivity at RHIC. 相似文献
42.
Rules of Boron–Nitrogen Doping in Defect Graphene Sheets: A First‐Principles Investigation of Band‐Gap Tuning and Oxygen Reduction Reaction Catalysis Capabilities
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Introduction of defects and nitrogen doping are two of the most pursued methods to tailor the properties of graphene for better suitability to applications such as catalysis and energy conversion. Doping nitrogen atoms at defect sites of graphene and codoping them along with boron atoms can further increase the efficiency of such systems due to better stability of nitrogen at defect sites and stabilization provided by B?N bonding. Systematic exploration of the possible doping/codoping configurations reflecting defect regions of graphene presents a prevalent doping site for nitrogen‐rich BN clusters and they are also highly suitable for modulating (0.2–0.9 eV) the band gap of defect graphene. Such codoped systems perform significantly better than the platinum surface, undoped defect graphene, and the single nitrogen or boron atom doped defect graphene system for dioxygen adsorption. Significant stretching of the O?O bond indicates a lowering of the bond breakage barrier, which is advantageous for applications in the oxygen reduction reaction. 相似文献
43.
Mukhopadhyay Anandamoy Chattopadhyay Souradip Barua Amlan K. 《Nonlinear dynamics》2020,100(2):1143-1172
Nonlinear Dynamics - We investigated an incompressible viscous liquid film flow over a rotating vertical cylinder of radius R and of infinite length rotating with a uniform angular velocity... 相似文献
44.
To exploit the parallelism of optics in data processing,a suitable number system and an efficient encoding/decoding scheme for handling the data are very essential.In the field of optical computing and parallel information processing,several number systems like binary,quaternary,octal,hexadecimal,etc.have been used for different arithmetic and algebraic operations.Here,we have proposed an all-optical conversion scheme from its binary to its other 2n radix based form with the help of terahertz optical asymmetric demultiplexer (TOAD) based tree-net architecture. 相似文献
45.
D. Chattopadhyay 《Applied Physics A: Materials Science & Processing》1991,53(1):35-42
Transport properties of the electrons itinerant two dimensionality in a square quantum well of In0.53Ga0.47As are studied in the framework of Fermi-Dirac statistics including the relevant scattering mechanisms. An iterative solution of the Boltzmann equation shows that the ohmic mobility is controlled by LO phonon scattering at room temperature, but below 130 K alloy scattering is predominant. The calculated mobilities with a suitable value of the alloy scattering potential agree with the experimental results over a range of lattice temperature. For lattice temperatures below 25 K where the carrier energy loss is governed by the deformation potential acoustic scattering, the warm electron coefficient is found to be negative. Its magnitude decreases with increasing lattice temperature and is greater for larger channel widths. Values of the small-signal AC mobility of hot electrons at a lattice temperature of 4.2 K are obtained for different sheet carrier densities and channel widths. Cut-off frequencies around 100 GHz are indicated.Dedicated to H.-J. Queisser on the occasion of his 60th birthday 相似文献
46.
The effect of strong inversion in a metal-SiO2-p-Si system has been studied. It is seen that the plot of barrier height versus metal work function of the system becomes nonlinear when the metal work function is lowered below a critical value. These values of critical work function are calculated and analysed for different values of doping and oxide charge. 相似文献
47.
R. Chattopadhyay 《Journal of Optimization Theory and Applications》1972,9(3):216-219
This paper presents a method for solving a class of constrained optimization problems in finite-dimensional spaces. This type of problem usually arises in connection with parameter optimization in engineering design. Most often, these problems consist of incorporating upper and/or lower bounds on the variables in otherwise unconstrained optimization problems. The proposed method replaces the original optimization problem withm constraints (m>1) by a sequence of optimization problems with one constraint only. The theory behind this method is discussed in the subsequent sections.This research was supported by NSF Grant No. GK-4984. 相似文献
48.
Chattopadhyay J Sadana AK Liang F Beach JM Xiao Y Hauge RH Billups WE 《Organic letters》2005,7(19):4067-4069
[reaction: see text] Carbon nanotube salts prepared by treating single-wall carbon nanotubes (SWNTs) with lithium in liquid ammonia react readily with aryl iodides to give SWNTs functionalized by aryl groups. 相似文献
49.
Adams J Adler C Aggarwal MM Ahammed Z Amonett J Anderson BD Anderson M Arkhipkin D Averichev GS Badyal SK Balewski J Barannikova O Barnby LS Baudot J Bekele S Belaga VV Bellwied R Berger J Bezverkhny BI Bhardwaj S Bhaskar P Bhati AK Bichsel H Billmeier A Bland LC Blyth CO Bonner BE Botje M Boucham A Brandin A Bravar A Cadman RV Cai XZ Caines H Calderón de la Barca Sánchez M Carroll J Castillo J Castro M Cebra D Chaloupka P Chattopadhyay S Chen HF Chen Y Chernenko SP Cherney M Chikanian A Choi B 《Physical review letters》2004,92(17):171801
Measurements of the production of forward high-energy pi(0) mesons from transversely polarized proton collisions at sqrt[s]=200 GeV are reported. The cross section is generally consistent with next-to-leading order perturbative QCD calculations. The analyzing power is small at x(F) below about 0.3, and becomes positive and large at higher x(F), similar to the trend in data at sqrt[s]< or =20 GeV. The analyzing power is in qualitative agreement with perturbative QCD model expectations. This is the first significant spin result seen for particles produced with p(T)>1 GeV/c at a polarized proton collider. 相似文献
50.