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Propagation of elastic wave in nanoporous material with distributed cylindrical nanoholes

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Science China(Physics,Mechanics & Astronomy) 2013年第8期56卷 1542-1550页

作者： QIANG FangWei WEI PeiJun LIU XiQiang department of Applied Mechanics University of Science and Technology Beijin department of Mathematics & Physics PLA University of Science and Technology

The effective propagation constants of plane longitudinal and shear waves in nanoporous material with random distributed parallel cylindrical nanoholes are studied. The surface elastic theory is used to consider the surface stress effects and to derive the nontraditional boundary condition on the surface of nanoholes. The plane wave expansion method is used to obtain the scattering waves from the single nanohole. The multiple scattering effects are taken into consideration by summing the scat- tered waves from all scatterers and performing the configuration averaging of random distributed scatterers. The effective propagation constants of coherent waves along with the associated dynamic effective elastic modulus are numerically evaluat- ed. The influences of surface stress are discussed based on the numerical results.

关键词：分布式并行纳米孔洞纳米材料弹性理论圆柱形波的传播平面波展开方法表面应力

Tribological performance of tributylmethylammonium bis(trifluoromethylsulfonyl)amide as neat lubricant and as an additive in a polar oil

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Friction 2019年第3期7卷 282-288页

作者： Rubén GONZáLEZ Diego RAMOS David BLANCO Alfonso FERNáNDEZ-GONZáLEZ Jose L.VIESCA Mark HADFIELD Antolin HERNáNDEZ BATTEZ department of Marine Science and Technology University of OviedoAsturias 33203Spain department of Construction and Manufacturing Engineering University of OviedoAsturias 33203Spain department of Physical and Analytical Chemistry University of OviedoAsturias 33006Spain department of Design and Engineering Bournemouth UniversityPoole BH12 5BBUK

The ionic liquid(IL) tributylmethylammonium bis(trifluoromethylsulfonyl)amide([N4441][NTf2]) was used as neat lubricant and as an additive(1.5 wt%) in a polar oil to study its friction and wear reducing *** tests were completed for 90 minutes at room temperature and 100 °C in a reciprocating configuration at loads of 30 and 70 N,10 Hz-frequency,and 4 mm stroke *** volume was measured by confocal microscopy and the surface-IL interaction determined by *** main findings were that neat IL showed the best tribological behavior;the IL-containing mixture behaved similar to the base oil regarding friction,however outperformed the antiwear behavior of the base oil under higher temperature;surface-IL chemical interaction was found mainly at 100 °C.

关键词： ionic liquid additive friction wear polar oil

Ozone electrogeneration on Pt-TaO_y sol-gel film modified titanium electrode: Effect of electrode composition on the electrocatalytic activity

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Journal of Energy Chemistry 2015年第2期24卷 178-184页

作者： Mohamed I. Awad Shunsuke Sata Kazuhiro Kaneda Mineo Ikematsu Takeo Ohsaka department of Electronic Chemistry Interdisciplinary Graduate School of Science and EngineeringTokyo Institute of Technology Chemistry department Faculty of Science Cairo University 12613Egypt Chemistry department Faculty of Applied Sciences Umm Al-Qura University department of the Humanities Ibaraki College National Institute of Technology Faculty of Engineering Tokyo University of Science

This work examines the ozone electrogeneration （OE） at a binary coating of different nominal compositions （Pt）x-（TaOy）（100-x）, where x （percentage in the precursor solution） varied between 1% and 100%, coated on titanium substrate prepared by a sol-gel technique, The OE is performed in an artificial tap water at room temperature （25 ℃）. The percentages of Pt and Tatu in the coating significantly affect the electro- catalytic activity towards oxygen evolution. The oxygen evolution was retarded to a different extent based on the electrode composition. The largest retardation was obtained at the （Pt）10-（TaOy）90 electrode （ca. 480 mV positive shift） as compared with the （Pt）100-（TaOy）0 electrode. This was reflected in a high current efficiency （CE） of OE （ca. 19.3%） at the former electrode. This value is considered to be among the highest values reported for OE at 25℃ in neutral media. The composite electrodes were characterized by voltammetric and surface techniques. A plausible explanation for the change of the efficiency of OE with the electrode composition is given based on the electrochemical results.

关键词： ozone electrocatalysis oxygen evolution dimensionally stable anode sol-gel

纳米黏土与再生聚酯纤维混合处理黏土砂的抗剪强度

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Journal of Central South University 2022年第1期29卷 259-269页

作者： Mehrdad KHOLGHIFARD Babak AMINI BEHBAHANI department of Civil Engineering Yasooj BranchIslamic Azad UniversityYasooj ***Iran

近年来,以纳米尺度和纳米颗粒以及定向或随机分布的离散单元(如纤维)来加固土体的材料已被广泛应用于岩土工程中。本研究的主要目的是研究纳米黏土与再生聚酯纤维混合作为一种新的稳定材料对土壤力学行为的影响。对于未强化和三种纤维... 详细信息

近年来,以纳米尺度和纳米颗粒以及定向或随机分布的离散单元(如纤维)来加固土体的材料已被广泛应用于岩土工程中。本研究的主要目的是研究纳米黏土与再生聚酯纤维混合作为一种新的稳定材料对土壤力学行为的影响。对于未强化和三种纤维含量介于0.1%和0.5%的强化土壤标本,以及三种纳米黏土含量介于0.5%和1.5%的土壤进行排干剪切和压缩测试。结果表明,纳米黏土-再生聚酯纤维与土壤混合后,土壤的抗剪强度提高了41%,黏聚力提高了174%。此外,纤维粗糙的波状表面使土颗粒之间产生粘结和摩擦,阻止土颗粒的运动,从而提高土的强度。

关键词：土壤处理纳米黏土再生聚酯纤维抗剪强度黏土砂

A Dark Energy Model with Higher Derivative and Cosmological Evolution

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Chinese Physics Letters 2009年第10期26卷 232-235页

作者：张晓菲刘汇慧 department of Physics and Electronic Science Binzhou College Shandong 256600 department of Physics Henan University of Science and Technology Luoyang 471003

We construct dark energy models which have high derivative terms. In the framework of a single scalar field model with a higher derivative, the equation of state （EOS） ω might have some special character in the evolvement, which states that the universe will evolve in some interesting ways. We study the different kinds of dark energy models, and classify them into several genera by their character in the evolvement.

关键词： sea surface nonliear interaction numerical method

An isomorphism theorem for Teichmüller curves

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Science China Mathematics 2006年第5期49卷 577-586页

作者： CAI Yongmao SHEN Yuliang department of Mathematics Suzhou University Suzhou 215006China Department of Mathematics Suzhou University Suzhou 215006China

It is proved that for any Fuchsian group Γ such that H/Γ is a hyperbolic Riemann surface, the Teichmüller curve V(Γ) has a unique complex manifold structure so that the natural projection of the Bers fiber space F(Γ) onto V(Γ) is holomorphic with local holomorphic *** isomorphism theorem for Teichmüller curves is deduced, which generalizes a classical result that the Teichmüller curve V(Γ) depends only on the type of Γ and not on the orders of the elliptic elements of Γ when H/Γ is a compact hyperbolic Riemann surface.

关键词： Teichmüller space, Bers fiber space, Teichmüller curve, biholomorphic isomorphism.

surface-plasmonic sensor using a columnar thin film in the grating-coupled configuration [Invited]

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Chinese Optics Letters 2021年第8期19卷 121-129页

作者： Kiran Mujeeb Muhammad Faryad Akhlesh Lakhtakia Julio V.Urbina department of Electronics Quaid-i-Azam UniversityIslamabad 45320Pakistan department of Physics Lahore University of Management SciencesLahore 54792Pakistan department of Engineering Science and Mechanics The Pennsylvania State UniversityUniversity ParkPennsylvania 16802USA department of Electrical Engineering The Pennsylvania State UniversityUniversity ParkPennsylvania 16802USA

The excitation of a surface-plasmon-polariton(SPP) wave guided by a columnar thin film(CTF) deposited on a one-dimensional metallic surface-relief grating was investigated for sensing the refractive index of a fluid infiltrating that CTF. The Bruggemann homogenization formalism was used to determine the relative permittivity scalars of the CTF infiltrated by the fluid. The change in the refractive index of the fluid was sensed by determining the change in the incidence angle for which an SPP wave was excited on illumination by a p-polarized plane wave, when the plane of incidence was taken to coincide with the grating plane but not with the morphologically significant plane of the CTF. Multiple excitations of the same SPP wave were found to be possible, depending on the refractive index of the fluid, which can help increase the reliability of results by sensing the same fluid with more than one excitation of the SPP wave.

关键词： metal grating multiple excitation rigorous coupled-wave approach sensitivity surface-plasmon-polariton wave

Corrosion inhibition of carbon steel in hydrochloric acid by cationic arylthiophenes as new eco-friendly inhibitors: Experimental and quantum chemical study

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Chinese Journal of Chemical Engineering 2021年第12期34卷 197-217页

作者： Abd El-Aziz S.Fouda Mohamed A.Ismail Abdulraqeb A.Al-Khamri Ashraf S.Abousalem department of Chemistry Faculty of ScienceEl-Mansoura UniversityEl-Mansoura 35516Egypt department of Chemistry Faculty of EducationArts and SciencesUniversity of Saba RegionMaribYemen Quality Control Laboratory Operations DepartmentJotunEgypt

This study describes the adsorption behavior of three arylthiophene derivatives namely:2-(4-amidino-3-fluorophenyl)-5-[4-methoxy phenyl] thiophene dihydrochloride salt(MA-1217),2-(4-amidinophenyl)-5-[4-chlorophenyll thiophene dihydrochloride salt(MA-1316) and 2-(4-amidino-3-fluorophenyl)-5-[4-ch lorophenyllthiophene dihydrochloride salt(MA-1312) at C-steel in 1.0 mol·L^(-1) HCl interface using experimental and theoretical *** and mass loss measurements showed that the inhibition efficiency(IE) of the arylthiophene derivatives increases with increasing concentrations and exhibited maximum efficiency 89% at 21×10^(-6) mol·L^(-1)(MA-1217) by mass loss *** investigated arylthiophene derivatives obey the Langmuir adsorption *** polarization studies the arylthiophene derivatives act as mixed-type *** analysis were carried out and *** mode of orientation and adsorption of inhibitor molecules on C-steel surface was studied using molecular dynamics(MD) *** chemical parameters as well as the radial distribution function indices and binding energies confirm the experimental results.

关键词： Carbon steel Corrosion inhibition Adsorption Arylthiophene derivatives Polarization Electrochemical frequency modulation

Formation and Biomimetic Deposition of Bone-like Hydroxyapatite on Wollastonite-gypsum Composites

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Journal of Bionic Engineering 2018年第5期15卷 894-906页

作者： Yaser Greish Nuha Attia Abdel-Hamid Mourad department of Chemistry College of Science United Arab Emirates University AI Ain UAE department of Ceramics National Research Centre Cairo Egypt department of Mechanical Engineering College of Engineering United Arab Emirates University Al Ain UAE Mechanical Design department Faculty of Engineering at Mataria Helwan University Cairo Egypt

Bone cements are often used for bone repair and fixation. The main objective of formulating a bone cement is to achieve structure and properties similarity to bone. In addition, bioactivity of a bone cement provides a major advantage that helps achieving better binding and interaction with the surrounding tissues. In the current study, gypsum was used as a matrix for a composite that comprises highly crys- talline prestine and acid-treated wollastonite （CaSiO3） fibers. Composites made by mixing their powder precursors with deionized water at room temperature, were investigated for their composition using X-ray diffraction （XRD） and Thermogravimetric Analysis （TGA）, for their microstructure using Scanning Electron Microscopy （SEM）, for their compressive strengths and modulus of elasticity, and for setting time measurements. In addition, cement composites were evaluated for their preliminary bioactivity in a protein-free Simulated Body Fluid （SBF） for up to 14 days. Results show the improvement of mechanical properties and bioactivity of the composites using acid-treated wollastonite fibers. This was attributed to the formation of hydrated silica layer on the surface of the acid-treated fibers which improved the binding with the gypsum matrix and provided nucleating sites for the deposition of bone-like apatite spherolites from SBF media.

关键词： gypsum wollastonite bone cement biomimetic SBF microstructure