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Some Arithmetic on the Hardy Sums s_2(h,k) and s_3(h,k)

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Acta mathematica Sinica,English Series 2004年第2期20卷 193-200页

作者： mümün CAn Department of mathematics Akdeniz University07058AntalyaTurkey

In this work, Rademacher’s two questions about Dedekind sums are applied to the Hardy sums s 2(h, k) and s 3(h, k). Some relations between these sums are obtained and some inequalities are given.

关键词： Dedekind Sums Hardy Sums

On the dielectric response function and dispersion relation in strongly coupled magnetized dusty plasmas

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Chinese Physics B 2018年第10期27卷 465-470页

作者： m Shahmansouri n Khodabakhshi Department of Physics Faculty of ScienceArak University

Using the generalized viscoelastic fluid model, we derive the dielectric response function in a strongly coupled dusty magnetoplasma which reveals two different dust acoustic（DA） wave modes in the hydrodynamic and kinetic limits. The effects of the strong interaction of dust grains and the external magnetic on these DA modes, as well as on the shear wave are examined. It is found that both the real and imaginary parts of DA waves are significantly modified in strongly coupled dusty magnetoplasmas. The implications of our results to space and laboratory dusty plasmas are briefly discussed.

关键词： dusty plasma strongly coupled plasma magnetoplasma dielectric response function

Atmospheric pressure gliding arc discharge plasma treatments for improving germination, growth and yield of wheat

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Plasma Science and Technology 2018年第11期20卷 90-100页

作者： n C ROY m m HASAn A H KABIR m A REZA m R TALUKDER A n CHOWDHURY Plasma Science and Technology Laboratory Department of Applied Physics and Electronic EngineeringUniversity of Rajshahi Rajshahi 6205 Bangladesh Department of Agronomy and Agricultural Extension University of Rajshahi Rajshahi 6205 Bangladesh Depatment of Botany University of Rajshahi Rajshahi 6205Bangladesh Department of Genetic Engineering and Biotechnology University of Rajshahi Rajshahi 6205Bangladesh Bangladesh Council of Scientific and Industrial Research Laboratory Rajshahi Rajshahi 6206Bangladesh

Wheat （Triticum aestivum） seeds were treated with atmospheric pressure gliding arc discharge plasmas to investigate the effects on water absorption, seed germination rate, seedling growth and yield in wheat. The surface architectures and functionalities of the seeds were found to modify due to plasma treatments. 6 rain treatment was provided 95%-100% germination rate. For the treatment duration of 3 and 9 rain the growth activity, dry matter accumulation, leaves chlorophyll contents, longest spikes, number of spikes/spikelet and total soluble protein content in shoots were improved. The grain yield of wheat was increased ,--20% by 6 min treatment with H2O/O2 plasma with respect to control.

关键词： atmospheric pressure gliding arc discharge plasmas wheat germination growth improvement total soluble protein

OH and O radicals production in atmospheric pressure air/Ar/H_2O gliding arc discharge plasma jet

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Plasma Science and Technology 2017年第12期19卷 71-80页

作者： n C ROY m R TALUKDER A n CHOWDHURY Plasma Science and Technology Laboratory Department of Applied Physics and Electronic EngineeringUniversity of RajshahiRajshahi 6205Bangladesh Bangladesh Council of Scientific and Industrial Research Laboratory Rajshahi Rajshahi 6206Bangladesh

Atmospheric pressure air/Ar/H_2O gliding arc discharge plasma is produced by a pulsed dc power supply. An optical emission spectroscopic（OES） diagnostic technique is used for the characterization of plasmas and for identifications of OH and O radicals along with other species in the plasmas. The OES diagnostic technique reveals the excitation Tx？≈？5550–9000 K, rotational Tr？≈？1350–2700 K and gas Tg？≈？850–1600 K temperatures, and electron density n？（1.1-1.9） ′101 4 cm^（-3） e under different experimental conditions. The production and destruction of OH and O radicals are investigated as functions of applied voltage and air flow rate. Relative intensities of OH and O radicals indicate that their production rates are increased with increasing Ar content in the gas mixture and applied voltage. nereveals that the higher densities of OH and O radicals are produced in the discharge due to more effective electron impact dissociation of H_2O and O_2 molecules caused by higher kinetic energies as gained by electrons from the enhanced electric field as well as by enhanced n *** productions of OH and O are decreasing with increasing air flow rate due to removal of Joule heat from the discharge region but enhanced air flow rate significantly modifies discharge maintenance properties. Besides, Tgsignificantly reduces with the enhanced air flow rate. This investigation reveals that Ar plays a significant role in the production of OH and O radicals.

关键词： reactive oxygen species(ROS) optical emission spectroscopy(OES) gliding arc discharge plasma kinetics broadening mechanism

Heat Capacity and Thermal Expansion of Water and Helium

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Journal of Thermal Science 2017年第2期26卷 125-131页

作者： n.m.Putintsev D.n.Putintsev Department of Chemistry Murmansk State Technical UniversitySt.Sport 13183010MurmanskRussia Institute for Systems Analysis Federal Research Center《Computer Science and Controb》of the Russian Academy of SciencesPr.60-Letiya Oktyabrya9117312MoscowRussia

Original expressions for heat capacity CV and its components, vibrational and configurational components of thermal expansion coefficient were established. The values of CV, Cvib, Cconf, Cvib and Cconf for water and h... 详细信息

关键词： heat capacity thermal expansion coefficient isothermal compressibility vibrational input configurational input water helium 4.

Gas pressure effect on plasma transport in a magnetic-filtered radio-frequency plasma source

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Plasma Science and Technology 2020年第6期22卷 103-109页

作者： n OUDInI m m ALIm R TADJInE A BEnDIB Laboratoire des Plasmas de Décharges Centre de Développement des Technologies AvancéesCitédu 20 Aout BP 17 Baba Hassen16081 AlgiersAlgeria Laboratoire d’Electronique Quantique Facultéde PhysiqueUSTHBEl Alia BP 32Bab Ezzouar 16111AlgiersAlgeria

Volume negative ion production relies on a magnetic filter(mF),where the plasma downstream of the mF is characterized by a strip-like pattern that consists of a bright and dense plasma *** this work,we study,in a radio-frequency plasma source,the effects of operating pressure on this *** investigation,conducted using a Langmuir probe,shows that the plasma uniformity might be controlled through the gas ***,the operating pressure determines on which hemi-cylinder(side of magnetic field lines)the strip *** side inversion of the high-density plasma hemi-cylinder is due to an inversion of an ambipolar electric field that changes the E?×?B drift direction.

关键词： magnetic filter radio-frequency plasma source Langmuir probe E×B drift ambipolar electric field

Advanced hydrogen storage of the mg–na–Al system:A review

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Journal of magnesium and Alloys 2021年第4期9卷 1111-1123页

作者： n.A.Ali m.Ismail Energy Storage Research Group Faculty of Ocean Engineering Technology and InformaticsUniversiti Malaysia Terengganu21030 Kuala NerusTerengganuMalaysia

A solid-state storage system is the most practical option for hydrogen because it is more convenient and *** hydrides,especially mgH_(2),are the most promising materials that offer high gravimetric capacity and good ***,the practical application of mgH_(2) is restricted by slow sorption kinetics and high stability of thermodynamic *** storage performance of mgH_(2) was enhanced by introducing the mg–na–Al system that destabilises mgH_(2) with naAlH_(4).The mg–na–Al system has superior performance compared to that of unary mgH_(2) and naAlH_(4).To boost the performance of the mg–na–Al system,the ball milling method and the addition of a catalyst were *** mg–na–Al system resulted in a low onset decomposition temperature,superior cyclability and enhanced kinetics *** Al_(12)mg_(17) and namgH_(3) that formed in situ during the dehydrogenation process modify the reaction pathway of the mg–na–Al system and alter the thermodynamic *** this paper,the overview of the recent progress in hydrogen storage of the mg–na–Al system is *** remaining challenges and future development of mg–na–Al system are also *** paper is the first review report on hydrogen storage properties of the mg–na–Al system.

关键词： mg-na-Al system mgH_(2) naAlH_(4) Al_(12)mg_(17) hydrogen storage

magnetic,dielectric and electrical modulus of Ce^(3+) doped cobalt-magnesium ferrite nanoparticles

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Journal of Rare Earths 2024年第2期42卷 373-382,I0005页

作者： n.m.Basfer Hanaa Almaghamsi Department of Physics Umm AL-Qura UniversityMakkahSaudi Arabia Physics Department College of Science and ArtKing Abdulaziz UniversityPOB344Rabigh291Saudi Arabi

In this work,the magnetic,dielectric properties and electric modulus of Ce^(3+) substituted cobaltmagnesium(Co_(0.7)mg_(0.3)Ce_(x)Fe_(2-x)O_4)(labeled as CmCF) ferrite nanoparticles were investigated in *** magnetization decreases from 50.05 to 34.87 emu/g for further substituting Ce^(3+) ***,coercivity increases from 738.22 Gs for the CmCFO sample to 912.10 Gs for the CmCF2 sample,then decreases monotonically to 762.1 Gs for the CmCF5 *** cerium content and particle size play important roles in controlling the magnetization and coercivity of the CmCF *** CmCF nanoferrites are suitable for microwave applications since their high-frequency response ranges from 7.72 to 11.07 *** CmCF nanoferrites' dielectric parameter dispersion exhibits normal *** pristine Co-mg nanoferrite only has ε' value of 28.25,but the nanoferrite mCmF2 has ε' value of365.03,with an enhancing ratio of 1192%.The conduction mechanism of the mCmF nanoferrites was determined by fitting the σ_(ac) results via the Jonscher power *** 653 K,large polaron tunnelling is thought to be responsible for this conduction process,which is followed by electron barrier hopping at higher ***-Cole diagrams at different temperatures,assuring the contributions of the grains and their boundaries at lower temperatures(653 K) and only the grains at higher *** on our results,the CmCF nanoferrites hold magnetic and semiconducting nature,which can be used in magnetic devices and dielectrics in lower-frequencies or conductors in higher-frequencies.

关键词： nanoferrites Rare earth ions magnetic properties Dielectric parameters Impedance spectroscopy

Analytical Determination of Collisionless Sheath Properties for Triple Frequency Capacitively Coupled Plasma

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Plasma Science and Technology 2015年第2期17卷 141-146页

作者： m.T.RAHmAn m.n.A.DEWAn Department of Electrical and Electronic Engineering Bangladesh University of Engineering and Technology

A triple frequency capacitively coupled plasma （TF-CCP） has been considered to investigate the behavior of the sheath parameters. A self-consistent time-independent collisionless model has been developed. The sheath width and potential are calculated using the present model and compared with those calculated using a single-frequency （SF）, a dual-frequency （DF） and a triple-frequency （TF） model for time independent collisionless cases. The sheath motion and sheath potential are found to be larger compared with those of SF and DF CCPs for an inhomogeneous sheath, and that of TF CCP for a homogeneous sheath. The effects of the source parameters, i.e., current magnitudes, frequencies and phase difference, on the sheath parameters are investigated. The sheath parameters show higher values at higher source currents whereas they decrease with the increase of excitation frequencies. It has also been found that, by the proper choice of source frequencies and phase differences, it is possible to adjust the energy of ions when they hit the electrode.

关键词： capacitively coupled plasma collisionless sheath triple frequency sheath parameters