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Chinese Physics Letters 2014年第4期31卷 110-113页

作者： H. Tashakori b. Khoshnevisan f. Kanjouri faculty of Physics University of Kashan Kashan Iran faculty of Physics Kharazmi University Karaj Iran

We use density functional perturbation theory based on the pseudo-potential to calculate the phonon spectrum, phonon density of states, specific heat capacity and mechanical properties of pristine and cobalt doped （5,0） single wall carbon nanotube （CNT）. In the calculations, we consider one Co atom in the center of the unit cell of the tube and it is shown that the pristine （5~0） CNT is nonmagnetic while the Co-doped tube becomes magnetic. Young＇s modulus for both systems is about 1 TPa （＇after Co-doping it goes slightly higher） and the Poisson ratio for the pristine tube becomes quite a bit larger than the doped one. On the other hand, the calculated value of radial breath mode for the pristine CNT is in good agreement with the experimental reports while after Co-doping it is increased. In addition, heat capacity of the doped CNT is reduced, which leads to some important empirical applications.

关键词： CHEMICAL vapor deposition DENSITY functional theory PERTURbATION (Mathematics) CARbON nanotubes POISSON'S ratio

A Novel Approach to Predict the Stability Limits of Combustion Chambers with Large Eddy Simulation

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Journal of Thermal Science 2010年第3期19卷 261-265页

作者： b.Pritz f.Magagnato M.Gabi Department of fluid Machinery University of Karlsruhe Kaiserstr.1276131 KarlsruheGermany

Lean premixed combustion,which allows for reducing the production of thermal NOx,is prone to combustion *** is an extensive research to develop a reduced physical model,which allows-without time-consuming measurements-to calculate the resonance characteristics of a combustion system consisting of Helmholtz resonator type components (burner plenum,combustion chamber).for the formulation of this model numerical investigations by means of compressible Large Eddy Simulation (LES) were carried *** these investigations the flow in the combustion chamber is isotherm,non-reacting and excited with a sinusoidal mass flow *** a combustion chamber as a single resonator subsequently a coupled system of a burner plenum and a combustion chamber were *** this paper the results of additional investigations of the single resonator are *** flow in the combustion chamber was investigated without excitation at the *** was detected,that the mass flow rate at the outlet cross section is pulsating once the flow in the chamber is *** fast fourier transform of the signal showed that the dominant mode is at the resonance frequency of the combustion *** result sheds light on a very important source of self-excited combustion *** the LES can provide not only the damping ratio for the analytical model but the eigenfrequency of the resonator also.

关键词： compressible large-eddy simulation combustion instabilities oscillating flow damping ratio

Dust Acoustic Rotation Modes in Magnetized Complex Plasmas

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Chinese Physics Letters 2011年第7期28卷 214-216页

作者： b.farokhi f.Amini M.Eghbali Department of Physics Faculty of ScienceArak UniversityArak 38156-8-8349Iran

A theoretical investigation is made of the low-frequency electrostatic modes in a cylindrical system and in magnetized dusty *** linear dispersion relation of the rotational modes is *** discuss the difference between the magnetized and unmagnetized *** the dusty plasma is confined in a finite region,the void behavior is observed at high speed *** structures of different mode number solutions are illustrated.

关键词： cylindrical electrostatic illustrated

pH-distribution of cerium species in aqueous systems

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Journal of Rare Earths 2012年第6期30卷 559-562页

作者： b.bouchaud J.balmain *** f.Pedraza University of La Rochelle Laboratory of Engineering Science for the Environment LaSIE FRE-CNRS3474Avenue Michel Crépeau 17042 La Rochelle cedex 01FRANCE

Cerium-based oxide coatings can be obtained through either chemical or electrochemical processes on various conductor and semiconductor substrates. In both cases the films develop through a precipitation mechanism, which strongly depends on the solution chemistry. In the particular case of the electrolytic approach, the elaboration parameters play a key role on the interfacial pH modification thereby leading to an indirect precipitation mechanism. Indeed, the nucleation and growth mechanisms of crystallites and the composition of the resulting layers have been shown to be also strongly affected by the deposition conditions as well as by the substrate composition, which could in turn modify the protectiveness provided by such coatings. Therefore a better fundamental understanding of the system is required, in particular of the distribution of cerium-containing species in aqueous solution. To this end, the present work intended to develop a diagram showing the distribution as well as the relative amount of Ce（Ⅲ）/Ce（Ⅳ） species in aqueous media as a fimction of the pH range. The resulting pH-distribution diagram turned out to be a useful tool to predict the relevant precipitation mechanisms and species involved during the growth of ceriuna-containing films and to draw correlations with the characteristics of the as-deposited films.

关键词： pH-distribution diagram electrodeposition cerium-based oxide films precipitation mechanisms rare earths

Use of ferricyanide for gold and silver cyanidation

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中国有色金属学会会刊：英文版 2009年第3期19卷 714-718页

作者： f. XIE D. b. D REISINGER Department of Materials Engineering University of British Columbia

Low gold and silver leaching kinetics has been commonly observed in traditional gold-silver cyanidation process, especially in heap leaching and in situ leaching operations. The different mineralogy of gold and silver in the ores is suspected to be the main reason, e.g., the occurrence of low solubility acanthite (Ag2S) typically results in low overall silver extraction. Due to the low solubility of oxygen in cyanide solution, the reactivity and availability of oxidant is believed to be the critical limitation for gold and silver dissolution. The use of ferricyanide as the auxiliary oxidant for gold and silver cyanidation has been examined. The rotating disc test results prove the assistant effect of ferricyanide on increasing the dissolution rate of gold and silver. The potential use of ferricyanide in gold/silver cyanidation process is proposed based on the leaching results of actual ores.

关键词：氰化工艺金银浸出动力学铁助氧化剂氰化物溶液旋转圆盘溶解度

Numerical analysis for peristaltic transport of Carreau-Yasuda fluid with variable thermal conductivity and convective conditions

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Journal of Central South University 2015年第11期22卷 4467-4475页

作者： f.M.Abbasi T.Hayat b.Ahmad Department of Mathematics Comsats Institute of Information Technology Department of Mathematics Quaid-I-Azam University 45320 Nonlinear Analysis and Applied Mathematics (NAAM) Research Group Faculty of Science King Abdulaziz University

Peristalsis of Carreau-Yasuda fluid is investigated. Analysis is carried out in the presence of velocity slip and convective boundary conditions. Thermal conductivity of the fluid is taken to be temperature dependent. Lubrication analysis is used in the formulation of the problem. Resulting nonlinear system of equations is solved numerically. Impact of embedded parameters on the quantities of interest is examined through graphs and tables. Comparison of the behavior of the Carreau-Yasuda, Carreau and Newtonian fluid models is presented. Results show that the heat transfer rate at the wall for the Carreau fluid model is large when compared with the Newtonian or the Carreau-Yasuda fluid model. Also the heat transfer rate at the wall decreases with increase in the velocity slip and variable thermal conductivity parameters. further, an increase in the biot number reduces the fluid temperature by a considerable amount.

关键词： peristaltic transport Carreau-Yasuda fluid variabl

Effectiveness of Rice Husk and Sugarcane bagasse Ashes blended Cement in Improving Properties of Concrete

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Journal of Modern Physics 2023年第8期14卷 1-19页

作者： Johnson Adegaye adebola Catherine Mayowa Ikumapayi Chinwuba Arum Civil Engineering Department Federal University of Technology Akure Nigeria

This paper emphasized the use of rice husk ash (RHA) and sugarcane bagasse ash (SbA) in improving concrete properties, and also their combined effects on workability, compressive strength, flexural strength, permeability and water absorption capacity. Thus, in this study, the water-to-cement ratio was kept constant (0.45), the binder materials content for conventional mix was kept constant at (350 kg/m3) and the partial replacement of cement with RHASbA used was 5%, 10%, 15%, 20%, 25%, and 30% by weight of cement. The maximum compressive strength was noted at a 5% replacement level of cement with RHASbA. The Results showed that the optimum replacement of cement with RHASbA in concrete was 5%, which was found to increase the compressive strength by 15%, flexural strength by 3.4%, lowered permeability by 50%, lowered sorptivity by 11.34% as compared with control concrete at 90 days of curing time. The micro-structural test results further established that RHA and SbA have a high content of SiOb>2b> which enables them to be more reactive in concrete and also revealed that the presence of RHASbA depletes Ca(OH)b>2b> crystals, converting it into CaHb>2b>Ob>4b>Si (C-S-H gel) leading to the strengthening of bond within the concrete matrix.

关键词： Concrete Rice Husk Ash Sugarcane bagasse Ash Compressive Strength Permeability Sorptivity

Radiative capture of proton through the ^(14)N(p,γ)^(15)O reaction at low energy

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Chinese Physics C 2024年第4期48卷 183-192页

作者： b.f.Irgaziev Abdul Kabir Jameel-Un Nabi National University of Uzbekistan Tashkent 100174Uzbekistan Space and Astrophysics Research lab National Centre of GIS and Space ApplicationsDepartment of Space ScienceInstitute of Space TechnologyIslamabad 44000Pakistan University of Wah Quaid AvenueWah Cantt 47040PunjabPakistan

The CNO cycle is the main source of energy in stars more massive than our *** process defines the energy production,the duration of which can be used to determine the lifetime of massive *** cycle is an important tool for determining the age of globular *** proton capture via p+^(14)N→^(15)O+γ,at energies of astrophysical interest,is an important process in the CNO *** this project,we apply a potential model to describe both non-resonant and resonant reactions in the channels where radiative capture occurs through electric E1 *** employed the R-matrix method to describe the ongoing reactions via M1 resonant transitions,when it was not possible to correctly reproduce the experimental data using the potential *** partial components of the astrophysical S-factor are calculated for all possible electric and magnetic dipole transitions in ^(15)*** linear extrapolated S-factor at zero energy(S(0))agrees well with earlier reported values for all transition types considered in this *** on the value of the total astrophysical S-factor,depending on the collision energy,we calculate the nuclear reaction rates for p+^(14)N→^(15)O+γ.The computed rates agree well with the results reported in the NACRE II Collaboration and most recent existing measurements.

关键词： CNO cycle potential model R-matrix method cross-section astrophysical S-factor nuclear rates.

A new thermodynamically stable Nb_(2)Ni intermetallic compound phase revealed by peritectoid transition within binary Nb-Ni alloy system

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Journal of Materials Science & Technology 2022年第5期100卷 246-253页

作者： J.f.Zhao H.P.Wang b.Wei School of Physical Science and Technology Northwestern Polytechnical UniversityXi’an 710072China

A new intermetallic compound of thermodynamically stable Nb_(2)Ni phase is discovered within Nb-Ni binary system,refreshing the current situation that there are only three stable intermediate phases of Nb_(7)Ni_(6),NbNi_(3) and NbNi_(8).The new stable phase is generated from the peritectoid transition:(Nb)+Nb_(7)Ni_(6)→Nb_(2)Ni,and the transformation temperature is 1533 *** refreshes the current equilibrium Nb-Ni binary phase *** is confirmed by transmission electron microscopy and the annealing experiments,which is determined to be the fCC structure(Pearson:cf96,space grope:fd-3m O2,a=11.888A).furthermore,the equilibrium properties of Nb_(2)Ni phase are produced by density functional theory,including the formation energy,cohesive energy,bulk modulus and lattice constant.

关键词： Intermetallic compound Peritectoid transition Transmission electron microscopy Density functional theory Nb alloy

Diabetes mellitus: from molecular mechanism to pathophysiologyand pharmacology

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Medicine in Novel Technology and Devices 2023年第3期19卷 1-8页

作者： Oluwafemi Adeleke Ojo Hannah Sokolayam Ibrahim Damilare Emmanuel Rotimi Akingbolabo Daniel Ogunlakin adebola busola Ojo Phytomedicine Molecular Toxicologyand Computational Biochemistry Research Laboratory(PMTCB-RL)Department of BiochemistryBowen UniversityIwoNigeria Department of biochemistry Landmark UniversityOmu-AranNigeria Department of biochemistry Ekiti State UniversityAdo-EkitiNigeria

Diabetes mellitus is a metabolic disease characterized by high blood glucose levels and a range of other symptomsthat last for a long period of time. It has a rapid prevalence globally, and there is a possibility of the statisticdoubling in a few years. This review is aimed at evaluating the mechanism, pathophysiology, and pharmacologyof diabetes mellitus. The data used was sourced through a thorough review of scientific articles published in avariety of databases, including Springer, Scopus, Elsevier, Google Scholar, Wiley, Web of Science, PubMed, andTaylor & francis. furthermore, PhD and MSc theses were also used in compiling data. According to the literaturereview, diabetes mellitus is a persistent condition with various risk factors and serious complications that affectthe quality of life. However, research studies have helped in the prognosis, diagnosis, treatment, and managementof its different forms.

关键词： Mechanism Pathophysiology Pharmacology Diabetes mellitus