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101.
Solookinejad Gh. Jabbari M. Nafar M. Ahmadi Sangachin E. Asadpour S. H. 《International Journal of Theoretical Physics》2019,58(5):1359-1368
In this paper, we have suggested a configuration based on Rydberg atoms for adjusting properties of optical bistability (OB) and optical multistability (OM) via spontaneously generated coherence (SGC) in a unidirectional ring cavity. The Rydberg atoms consist of four energy levels interacts by a weak probe and a strong coupling fields, respectively. We have found that due to presence of SGC, threshold of OB and OM can be controlled when the strong light coupled the intermediate levels to the Rydberg state.
相似文献102.
Mohammad Mazloum-Ardakani Mohammad Ali Sheikh-Mohseni Bibi-Fatemeh Mirjalili Roya Ahmadi Mohammad Ali Mirhoseini 《催化学报》2015,(8):1273-1279
在金纳米粒子(AuNPs)上经苯硫酚衍生物(3,4二羟基苯基-偶氮-苯硫酚, DAT)自组装制得了一种新型纳米复合物,用于修饰玻璃碳电极(GCE/AuNP-DAT).采用循环伏安法研究了该新型电极的性质,并将其用作异丙肾上腺素(IP)电催化剂,考察了该纳米复合物的电催化活性,从而得到反应机理和催化反应速率常数.由于GCE/AuNP-DAT电极对尿酸氧化没有电催化活性,因此可将IP的氧化信号从该改进电极中分离出来,从而排除了尿酸对IP测定的干扰.该电极可作为传感器,当用于差动脉冲伏安法测定IP时,线性动态范围为1.0–1500.0μmol/L,检测极限为0.46μmol/L. 相似文献
103.
Numerical Algorithms - Recently, Axelsson and Salkuyeh in (BIT Numerical Mathematics, 59 (2019) 321–342) proposed the transformed matrix iteration (TMIT) method for solving a certain... 相似文献
104.
L. Mohammadzadeh A. Asgari S. Shojaei E. Ahmadi 《The European Physical Journal B - Condensed Matter and Complex Systems》2011,84(2):249-253
In this paper the excitons of armchair graphene nanoribbons with layers of different width and thickness have been investigated.
In this investigation, the band structure and energy gap of armchair graphene nanoribbons have been calculated using a tight-binding
model including edge deformation effects (all edge atoms have been passivated with hydrogen atoms). Also, by calculating the
conductance in armchair graphene nanoribbons (A-GNRs) optical absorption of armchair graphene nanoribbon in the single-electron
approximation has been obtained. Finally, the binding energy of excitons in armchair graphene nanoribbons has been calculated
using the Wannier model, Hartree-Fock approximation and the Bethe-Salpeter equation. 相似文献
105.
In this note, it is shown that the validity of the Auslander–Reiten conjecture for a given d-dimensional Cohen–Macaulay local ring R depends on its validity for all direct summands of d-th syzygy of R-modules of finite length, provided R is an isolated singularity. Based on this result, it is shown that under a mild assumption on the base ring R, satisfying the Auslander–Reiten conjecture behaves well under completion and reduction modulo regular elements. In addition, it will turn out that, if R is a commutative Noetherian ring and 𝒬 a finite acyclic quiver, then the Auslander–Reiten conjecture holds true for the path algebra R𝒬, whenever so does R. Using this result, examples of algebras satisfying the Auslander–Reiten conjecture are presented. 相似文献
106.
R. Malekfar G. Ahmadi A. Cheraghi J. Rohollahnejad F. Sahraiyan M. Khanzadeh 《Vibrational Spectroscopy》2009,51(2):308-312
KTP nanocrystallites were successfully grown by the modified Pechini method which uses a process for the preparation of the precursor polymeric resin. The products were characterized and examined by back-scattering micro-Raman spectroscopy, X-ray diffraction, FTIR transmission spectroscopy and near normal incidence IR reflection spectroscopy analysis. From the latter study and by using Kramers–Kronig analysis and dispersion relations, we have calculated and reported the typical behavior of real parts of refractive and dielectric indices in the spectral region of 400–4000 cm−1. 相似文献
107.
AbstractIt is well known that when a ring R satisfies ACC on right annihilators of elements, then the right singular ideal of R is nil, in this case, we say R is right nil-singular. Many classes of rings whose singular ideals are nil, but do not satisfy the ACC on right annihilators, are presented and the behavior of them is investigated with respect to various constructions, in particular skew polynomial rings and triangular matrix rings. The class of right nil-singular rings contains π-regular rings and is closed under direct sums. Examples are provided to explain and delimit our results. 相似文献
108.
Hadi Amiri Amir Charkhi Mohammad Ali Moosavian Seyyed Javad Ahmadi Hamed Nourian 《Chemical Papers》2017,71(9):1587-1596
The polydimethylsiloxane (PDMS) mixed matrix membrane with dispersed phase of nanozeolite silicalite-1 has been synthesized on polyethersulphone (PES) as a support, and its performance in the gas separation of xenon and krypton has been studied. For this purpose, nanozeolite silicalite-1 is synthesized by the hydrothermal clear solution method and is characterized by XRD and SEM analysis. In this research, the separation performance of MMM has also been compared with the polymeric PDMS membrane. Furthermore, the effect of feed pressure and loading percentage of nanozeolite in the polymeric matrix are evaluated. The results indicate that the addition of nanozeolite to the polymeric matrix improves its separation performance, and that the changes of the feed pressure have no major effect. The average permeability of the krypton and xenon gases through the PDMS polymeric membrane is calculated as 1.25 × 10?9 and 1.78 × 10?9 cm mol/(cm2 s kPa), respectively, while by adding only 5 wt% of nanosilicalite-1 to the polymeric matrix of the membrane, this amount increased to 1.82 × 10?9 and 8.07 × 10?9 cm mol/(cm2 s kPa), respectively. In addition, the presence of nanosilicalite-1 as the filler leads to an increase in the selectivity of xenon to krypton up to 4.38. 相似文献
109.
Nonlinear Dynamics - Different architectures and techniques have developed in the neuromorphic field to mimic and investigate the activity of biological neural networks. This paper presents a set... 相似文献
110.
Somayeh Ahmadi Alessio Roccon Francesco Zonta Alfredo Soldati 《Flow, Turbulence and Combustion》2018,100(4):979-993
In this work we study the turbulence modulation in a viscosity-stratified two-phase flow using Direct Numerical Simulation (DNS) of turbulence and the Phase Field Method (PFM) to simulate the interfacial phenomena. Specifically we consider the case of two immiscible fluid layers driven in a closed rectangular channel by an imposed mean pressure gradient. The present problem, which may mimic the behaviour of an oil flowing under a thin layer of different oil, thickness ratio h2/h1 =?9, is described by three main flow parameters: the shear Reynolds number Re τ (which quantifies the importance of inertia compared to viscous effects), the Weber number We (which quantifies surface tension effects) and the viscosity ratio λ = ν1/ν2 between the two fluids. For this first study, the density ratio of the two fluid layers is the same (ρ2 = ρ1), we keep Re τ and We constant, but we consider three different values for the viscosity ratio: λ =?1, λ =?0.875 and λ =?0.75. Compared to a single phase flow at the same shear Reynolds number (Re τ =?100), in the two phase flow case we observe a decrease of the wall-shear stress and a strong turbulence modulation in particular in the proximity of the interface. Interestingly, we observe that the modulation of turbulence by the liquid-liquid interface extends up to the top wall (i.e. the closest to the interface) and produces local shear stress inversions and flow recirculation regions. The observed results depend primarily on the interface deformability and on the viscosity ratio between the two fluids (λ). 相似文献