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Chinese Physics B 2020年第6期29卷 532-537页

作者： f Sobhani h heidarzadeh h Bahador Department of Electrical and Computer Engineering University of Mohaghegh ArdabiliArdabilIran

The cluster-shaped plasmonic nanostructures are used to manage the incident light inside an ultra-thin silicon solar *** we simulate spherical,conical,pyramidal,and cylindrical nanoparticles in a form of a cluster at the rear side of a thin silicon cell,using the finite difference time domain(fDTD)*** calculating the optical absorption and hence the photocurrent,it is shown that the clustering of nanoparticles significantly improves *** photocurrent enhancement is the result of the plasmonic effects of clustering the *** comparison,first a cell with a single nanoparticle at the rear side is *** four smaller nanoparticles are put around it to make a *** photocurrents of 20.478 mA/cm2,23.186 mA/cm2,21.427 mA/cm2,and 21.243 mA/cm2 are obtained for the cells using clustering conical,spherical,pyramidal,cylindrical NPs at the backside,*** values are 13.987 mA/cm2,16.901 mA/cm2,16.507 mA/cm2,17.926 mA/cm2 for the cell with one conical,spherical,pyramidal,cylindrical NPs at the backside,***,clustering can significantly improve the ***,the distribution of the electric field and the generation rate for the proposed structures are calculated.

关键词： clustering nanoparticles plasmonic solar cell localized surface plasmon resonance photocurrent finite difference time domain(fDTD)method light management

Charge susceptibilities of armchair graphene nanoribbon in the presence of magnetic field

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Chinese Physics B 2016年第9期25卷 511-517页

作者： h Rezania f Azizi Department of Physics Razi University

We present the behaviors of both dynamical and static charge susceptibilities of undoped armchair graphene nanoribbon using the Green＇s function approach in the context of tight binding model ***,the effects of magnetic field on the the plasmon modes of armchair graphene nanoribbon are investigated via calculating the correlation function of charge density *** results show that the increase of magnetic field makes the high-frequency plasmon mode for both metallic and insulating cases *** also show that low-frequency plasmon mode for metallic nanoribbon appears due to increase of magnetic ***,the number of collective excitation modes increases with ribbon width at zero magnetic ***,the temperature dependence of the static charge structure factor of armchair graphene nanoribbon is *** effects of both magnetic field and ribbon width on the static charge structure factor are discussed in detail.

关键词： armchair graphene nanoribbon Green's function

Elastic, thermodynamic, electronic, and optical properties of recently discovered superconducting transition metal boride NbRuB:An ab-initio investigation

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Chinese Physics B 2017年第10期26卷 339-347页

作者： f Parvin S h Naqib Department of Physics University of Rajshahi

The elastic, thermodynamic, electronic, and optical properties of recently discovered and potentially technologically important transition metal boride NbRuB, are investigated using the density functional formalism. Both generalized gradient approximation （GGA） and local density approximation （LDA） are used for optimizing the geometry and for estimating various elastic moduli and constants. The optical properties of NbRuB are studied for the first time with different photon polarizations. The frequency （energy） dependence of various optical constants complement quite well the essential features of the electronic band structure calculations. Debye temperature of NbRuB is estimated from the thermodynamical study. All these theoretical estimates are compared with published results, where available, and discussed in detail. Both electronic band structure and optical conductivity reveal robust metallic characteristics. The NbRuB possesses significant elastic anisotropy. Electronic features, on the other hand, are almost isotropic in nature. The effects of electronic band structure and Debye temperature on the emergence of superconductivity are also analyzed.

关键词： hard materials ternary borides DfT calculations electronic band structure optical properties superconductivity

Electrical Properties of Li-doped P-type ZnO Ceramics

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Journal of Materials Science & Technology 2009年第3期25卷 314-318页

作者： A.h. Salama f.f. hammad Physical Chemistry Department National Research Center Inorganic Chemistry Department National Research Center

Li-doped p-type ZnO ceramics were prepared by conventional methods according to the chemical formula Zn1-xLixO2 where x=0.5, 1.0, 1.5 and 2.0 mole fraction, respectively. The crystal structures of the prepared samples were studied by X-ray diffraction analysis. The dielectric properties （including dielectric constant ε′ and dielectric loss ε″） and dc-electrical conductivity [σ（Ω^-***^-1）] were investigated. The dielectric constant ε′ was sharply decreased at the low frequency range and independent on frequency at high frequency range. Otherwise, the dielectric loss ε″ varied with frequency and showed absorption peak located from 200 hz to 4 khz and moved to higher frequency as the concentration of Li＋ doped increased. It was found that dcelectrical conductivity logσ varied from -9 to -5 and the energy gap width were calculated by using Arrhenius equation. The p-type conductivity of Li-doped ZnO may be attributed to the formation of a Lizn-Lii donor complex, which is limited by reducing the amount of Lii.

关键词： P-type ZnO ceramics Dielectric constant Dielectric loss dc-conductivity

Effect of electrical discharge in water on concentration of nitrate solution

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Chinese Physics B 2017年第2期26卷 305-312页

作者： f Sohbatzadeh h Bagheri R Safari Department of Atomic and Molecular Physics Faculty of Basic Sciences University of Mazandaran Babolsar lra

In this work, the effect of electrical discharge on nitrate concentration is considered in aqueous solution. The atmospheric pressure plasma was produced by a high-voltage power supply at 27 k hz using pin-to-pin configuration. Air, argon,and argon/methane mixture were used to study the working gas effect. UV-VIS spectroscopy and ion chromatography were used to analyze the effect of the electrical discharge on nitrate concentration in deionized water. Optical emission spectroscopy（OES） was applied to diagnose active species inside and on the surface of the deionized water solution. The results of the present work showed that the atmospheric pressure electric discharge with air increases nitrate concentration while it remains constant using argon and argon/methane electrical discharges. It was also revealed that in the presence of air, the electrical discharge reduces p h, acidifying the solution and increasing solution conductivity due to production of extra nitrate ions. On the other hand, argon electrical discharge increases p h and conductivity due to production of Ohion in water.

关键词： electric discharge nitrate solution optical spectroscopy

Application of asymptotic iteration method to a deformed well problem

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Chinese Physics B 2016年第3期25卷 40-44页

作者： hakan Ciftci h f Kisoglu Gazi Universitesi Fen FakultesiFizik Bolumu 06500 Teknikokullar AnkaraTurkiye Maritime faculty Department of Basic SciencesMersin UniversityMersinTurkey

The asymptotic iteration method （AIM） is used to obtain the quasi-exact solutions of the Schr6dinger equation with a deformed well potential. for arbitrary potential parameters, a numerical aspect of AIM is also applied to obtain highly accurate energy eigenvalues. Additionally, the perturbation expansion, based on the AIM approach, is utilized to obtain simple analytic expressions for the energy eigenvalues.

关键词： asymptotic iteration method quasi-exact solutions perturbation method approximate solutions

Comparative chemical sensor for detection of chromium(Ⅵ) in aqueous solution

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Optoelectronics Letters 2025年第1期21卷 21-27页

作者： Sura h.AL-REKABI A.A.ALWAhIB Electrical Technique Department Al Suwayrah Technical Institute Middle Technical University Laser and Optoelectronics Department University of Technology-Iraq

A process for purifying aqueous solutions containing heavy and toxic metals such as chromium（Cr） has been investigated. One of the extremely harmful pollutants in rivers and seawater is the heavy metal ions due to their direct impacts on human, animals and plants are hexavalent Cr（Ⅵ）. Consequently, highly sensitive sensor to detect Cr is essential. Surface plasmon resonance（SPR） technique has attracted huge research interest in detecting heavy metals specifically. In this study, three types of prism-based SPR sensor, gold（Au）/silver（Ag）, Au/polyaniline（PANI） and Au/titanium dioxide（TiO2） nanostructured films, are investigated as potential sensing material to detect the presence of Cr（Ⅵ） ions in water. The base Au layer with thickness of 48.3 nm is deposited on a glass slide for all sensors. for Au/Ag, Au/PANI nanofibers and Au/TiO2sensor films, the Cr（Ⅵ） concentration is varied from 1 ppm to 15 ppm with sensitivity of 0.270 °ppm-1, 0.082 °ppm-1and 0.039 °ppm-1, respectively. Based on these results, the Au/PANI nanofibers are the most sensitive to Cr（Ⅵ） among the tested sensing materials.

关键词： Titanium dioxide

Local Entropy Production in Turbulent Shear flows:A Tool for Evaluating heat Transfer Performance

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Journal of Thermal Science 2006年第2期15卷 159-167页

作者： h. hERWIG f. KOCK hamburg University of Technology 21073 hamburg Germany. BMW 80788 Munich Germany

Performance evaluation of heat transfer devices can be based on the overall entropy production in these devices. In our study we therefore provide equations for the systematic and detailed determination of local entropy production due to dissipation of mechanical energy and due to heat conduction, both in turbulent flows. After turbulence modeling has been incorporated for the fluctuating parts the overall entropy production can be determined by integration with respect to the whole flow domain. Since, however, entropy production rates show very steep gradients close to the wall, numerical solutions are far more effective with wall functions for the entropy production terms. These wall functions are mandatory when high Reynolds number turbulence models are used. for turbulent flow in a pipe with an inserted twisted tape as heat transfer promoter it is shown that based on the overall entropy production rate a clear statement from a thermodynamic point of view is possible. for a certain range of twist strength there is a decrease in overall entropy production compared to the case without insert. Also, the optimum twist strength can be determined. This information is unavailable when only pressure drop and heat transfer data are given.

关键词： entropy production turbulent heat transfer wall functions

Increased salt sensitivity induced by sensory denervation: role of superoxide

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Acta Pharmacologica Sinica 2004年第12期25卷 60-66页

作者： Alex f ChEN,Donna h WANG Department of Medicine and Pharmacology & Toxicology Michigan State University East Lansing MI 48824 USA Department of Medicine and Pharmacology & Toxicology Michigan State University East Lansing MI 48824 USA

AIM: To test the hypothesis that production of superoxide in mesenteric resistance arteries is increased and con- tributes to the development of hypertension induced by sensory denervation plus high salt intake. METhODS: Newborn Wistar rats were given capsaicin 50 mg/kg sc on the 1st and 2nd d of life. After weaning, male rats were grouped as follows and treated for 3 weeks with: capsaicin pretreatment plus normal sodium diet (0.5 %, CAP-NS), CAP plus high sodium diet (4 %, CAP-hS), control plus NS (CON-NS), or CON-hS. Both tail-cuff systolic blood pressure and mean arterial pressure (MAP) were measured in each of the groups. Western blot analysis was used for measurement of manganese superoxide dismutase (MnSOD) and endothelial nitric oxide synthase (eNOS) in the mesenteric resistance arteries. Lucigenin chemiluminescence assay was used for superoxide production in the mesenteric resistance arteries. The Griess method was used for measurement of nitrite/nitrate levels in plasma. RESULTS: Both tail-cuff pressure and MAP were higher in CAP-hS compared with CAP-NS, CON-hS, and CON- NS rats (Ph MnSOD and eNOS in the mesenteric resistance arteries were increased in CAP-hS compared with CAP-NS, CON-hS, and CON-NS (Phowever, nitrite/nitrate levels in plasma were not different among 4 groups. Acute iv administration of tempol, a membrane-permeable superoxide scavenger, de- creased MAP in both CAP-hS and CON-hS when compared with their respective controls. however, the de- creases of MAP between these two groups were not different. Chronic treatment with tempol failed to prevent the development of hypertension in CAP-hS rats. Superoxideproduction in the mesenteric resistance arteries was increased in CAP-hS compared with CAP-NS, CON-hS, and CON-NS (Phowever, chronic treatment with tempol did not prevent the increase of mesenteric superoxideproduction in CAP-hS rats. CONCLUSIONS: Regardless of increased vascular MnSOD levels, salt

关键词： superoxides tempol afferent neurons capsaicin denervation dietary sodium chloride nitric oxide

A Note on the Invariance Properties and Conservation Laws of the Kadomstev–Petviashvili Equation with Power Law Nonlinearity

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Chinese Physics Letters 2011年第9期28卷 10-11页

作者： A h Bokhari f D Zaman K fakhar A h Kara Department of Mathematical Sciences King Fahd University of Petroleum and MineralsDhahran 31261Saudi Arabia Department of Mathematics Faculty of ScienceUniversiti Teknologi Malaysia81310 UTM SkudaiJohorMalaysia Ibnu Sina Institute for fundamental Science Studies Universiti Teknologi Malaysia81310 UTM SkudaiJohorMalaysia School of Mathematics University of the WitwatersrandJohannesburgWits 2050South Africa

first,we studied the invariance properties of the Kadomstev–Petviashvili equation with power law ***,we determined the complete class of conservation laws and stated the corresponding conserved densities which are useful in finding the conserved quantities of the *** point symmetry generators were also used to reduce the equation to an exact solution and to verify the invariance properties of the conserved flows.

关键词： equation conserved equation