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Adsorption isotherm and inhibition effect of a synthesized di-(m-Formylphenol)-1,2-cyclohexandiimine on corrosion of steel X52 in HCl solution

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Journal of Central South University 2016年第2期23卷 249-257页

作者： A.karimi I.Danaee H.Eskandari m.RashvanAvei Abadan Faculty of Petroleum Engineering Petroleum University of Technology Department of Chemistry K.N.Toosi University of Technology

The potential of di-(m-Formylphenol)-1,2-cyclohexandiimine as an environmentally friendly corrosion inhibitor for steel was investigated in 1 mol/L HCl using potentiodynamic polarization, electrochemical impedance spectroscopy and chronoamperometry measurements. All electrochemical measurements suggest that this compound is an excellent corrosion inhibitor for mild steel and the inhibition efficiency increases with the increase in inhibitor concentration. The effect of temperature on the corrosion behavior of mild steel with the addition of the Schiff base was studied in the temperature range from 25 °C to 65 °C. It is found that the adsorption of this inhibitor follows the Langmuir adsorption isotherms. The value of activation energy and the thermodynamic parameters such as ΔHads, ΔSads, Kads and ΔGads were calculated by the corrosion currents at different temperatures using the adsorption isotherm. The morphology of mild steel surface in the absence and presence of inhibitor was examined by scanning electron microscopy(SEm) images.

关键词： corrosion inhibitor Schiffbase adsorption Langmuir adsorption isotherm

Quantitative analysis of saindha salt using laser induced breakdown spectroscopy and cross-validation with ICP-mS

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Plasma Science and Technology 2020年第7期22卷 51-58页

作者： m QASIm m ANWAR-UL-HAQ m SHER AFGAN S U HAQ m A BAIG Department of Physics University of SargodhaSargodha 40100Pakistan Department of Energy&Power Engineering Tsinghua-BP Clean Energy CenterTsinghua UniversityBeijing 100084People’s Republic of China National Institute of Lasers and Optronics(NILOP) NiloreIslamabad 45650Pakistan National Center for Physics Quaid-i-Azam University CampusIslamabad 45320Pakistan

Saindha salt is considered to be more advantageous than the other edible salts for the patients suffering from diabetes,blood pressure and kidney *** explore the constituent elements of this salt,laser induced breakdown spectroscopy(LIBS) has been exploited for its qualitative and quantitative *** third harmonic(355 nm) of a Q-switched Nd:YAG laser has been used to produce the saindha salt plasma and the time integrated optical emission spectra were registered using a set of six miniature spectrometers covering the spectral range of 230-805 *** spectroscopic analysis of the emission spectra predominately revealed numerous neutral or singly ionized emission lines of Ca,mg,Na,K,Fe,Sr,Si,Li and *** laser produced plasma was characterized by calculating the electron temperature from the Boltzmann plots and the electron number density from the Stark broadened line profile as a function of laser irradiance and distance from the target *** relative concentration of the constituent elements was extracted by the integrated line intensities of the strongest spectral line of each element using the self-calibration-LIBS(SC-LIBS) and one-line calibration free-LIBS(OLCF-LIBS) *** cross-validation,the LIBS results have been compared with that obtained from the inductively coupled plasma-mass spectroscopy(ICP-mS) showing good agreement.

关键词： elemental analysis CF-LIBS plasma parameters

Luminescence Characteristics of LaAlO<sub>3</sub>:Eu<sup>3+</sup>Obtained by modified Pechini’s method

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Open Journal of Synthesis Theory and Applications 2017年第1期6卷 1-12页

作者： Alfredo morales Hernández mayra A. de León Alfaro Antonio Barrera Villatoro Ciro Falcony Teodoro Rivera montalvo Juan Zarate medina Instituto de Investigaciones en metalurgia y materiales Universidad Michoacana de San Nicolás de Hidalgo Morelia México Instituto Politécnico Nacional Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada Ciudad de México México Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional Ciudad de México México

The aim of the present work was to investigate the luminescent properties of europium-doped lanthanum aluminate (LaAlO3) powder prepared by modified Pechini (mP) method. Samples were prepared at different Eu3+ concentrations and calcined at 1600°C. Structural and morphology characterizations were obtained by X-ray diffraction (XRD), scanning electron microscopy (SEm), and transmission electron microscope (TEm). Luminescent properties were analyzed by photoluminescence (PL) and thermoluminescent phenomena. The XRD pattern shows pure lanthanum aluminate oxide LaAlO3 with a rhombohedral structure. Photoluminescence studies of the powders was related to 4f → 4f(5D0 → 7Fi) (i = 1, 2, 3, 4) transitions of Eu3+ ion, the most intense emission of Eu3+ in LaAlO3 was registered for the transition 5D0 → 7F1, for 5% of Eu3+. The recorded TL glow curves of excited samples showed a main TL peak, the main peak appeared its maximum as a function of excitation energy. The investigation demonstrates that polycrystalline LaAlO3:Eu3+ powders calcined at 1600°C have interesting luminescent characteristics.

关键词： modified Pechini method LaAlO3:Eu3+ Photoluminescence Thermoluminescence

Use of breakthrough experiment to evaluate the performance of hydrogen isotope separation for metal-organic frameworks m-mOF-74(m=Co, Ni, mg, Zn)

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Science China Chemistry 2020年第7期63卷 881-889页

作者： Yanan Si Wenjing Wang El-Sayed m.El-Sayed Daqiang Yuan State Key Laboratoty of Structural Chemistry Fujian Institute o f Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China University of the Chinese Academy of Sciences Beijing 100049China Chemical Refining Laboratory Refining DepartmentEgyptian Petroleum Research InstituteNasr CityCairoEgypt

The unique adsorption performance of metal-organic frameworks(mOFs) indicates a new direction for gas separation and purification. The low-temperature distillation, as a traditional technique for hydrogen isotope separation, is limited as it is a high energy-and cost-intensive process. Instead of utilizing such a conventional separation route, we use ordered microporous frameworks based on a physical adsorption mechanism to solve the challenge of hydrogen isotope separation. Herein we analyze m-mOF-74(m=Co, Ni, mg, Zn), featuring a hexagonal channel about 11 ? and high density of open metal sites, for their ability to separate and purify deuterium from the hydrogen isotope mixture by dynamic column breakthrough experiments. Our results show that the combination of the strength of binding sites, density of coordinatively unsaturated metal sites and hydrogen isotope adsorption capacity of materials renders Co-mOF-74 as an optimal adsorbent for the capture of deuterium from hydrogen isotope mixtures in a simulated industrial process.

关键词： hydrogen isotope separation breakthrough experiment mOF-74

Electron Density and Optical Emission measurements of SF_6/O_2 Plasmas for Silicon Etch Processes

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Plasma Science and Technology 2012年第4期14卷 316-320页

作者： m.m.mORSHED S.m.DANIELS National Centre for Plasma Science and Technology School of Electronic EngineeringDublin City UniversityGlasnevinDublin 9Ireland

This work investigates internal plasma process parameters using a hairpin resonance probe and optical emission spectroscopy. The dependence of electron density and atomic fluorine on the percentage of oxygen in an SF6/O2 discharge was measured using these methods. An RIE Oxford Instruments 80 plus chamber was used for the experiments. Two different process powers （100 W and 300 W） at a constant pressure （100 mTorr） were used, and it was found that the optical emission intensity of the 703.7 nm and 685.6 nm lines of atomic fluorine increased rapidly as oxygen was added to the SF6 discharge, reached their maximum at an O2 fraction of 20% and then decreased with further addition of oxygen. The plasma electron density was also strongly influenced by the addition of O2.

关键词： OES hairpin probe SF6 O2 electron density atomic fluorine

Relativistic symmetry of position-dependent mass particles in a Coulomb field including tensor interaction

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Chinese Physics B 2013年第3期22卷 122-128页

作者： m.Eshghi m.Hamzavi S.m.Ikhdair Physics Department Imam Hossein Comprehensive UniversityTehranIran Department of Science and Engineering Abhar BranchIslamic Azad UniversityAbharIran Department of Electrical and Electronic Engineering Near East University922022NicosiaNorthern CyprusTurkey Department of Physics Faculty of ScienceAn-Najah National UniversityNablusWest BankPalestine

The spatially-dependent mass Dirac equation is solved exactly for attractive scalar and repulsive vector Coulomb potentials,including a tensor interaction under the spin and pseudospin symmetric *** forms of the energy eigenvalue equation and wave functions are obtained for arbitrary spin-orbit quantum number κ.Some numerical results are also given,and the effect of tensor interaction on the bound states is *** is shown that tensor interaction removes the degeneracy between two states in the spin *** also investigate the effects of the spatially-dependent mass on the bound states under spin symmetric limit conditions in the absence of tensor interaction.

关键词： Dirac equation spin and pseudospin symmetries spatially-dependent mass tensor interaction

Effects of bi-kappa distributed electrons on dust-ion-acoustic shock waves in dusty superthermal plasmas

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Chinese Physics B 2013年第11期22卷 390-395页

作者： m.S.Alam m.m.masud A.A.mamun Department of Physics Jahangirnagar University Department of Physics Bangladesh University of Engineering and Technology (BUET)

The basic properties of dust-ion-acoustic （DIA） shock waves in an unmagnetized dusty plasma （containing inertial ions, kappa distributed electrons with two distinct temperatures, and negatively charged immobile dust grains） are investi- gated both numerically and analytically. The hydrodynamic equation for inertial ions has been used to derive the Burgers equation. The effects of superthermal bi-kappa electrons and ion kinematic viscosity, which are found to modify the basic features of DIA shock waves significantly, are briefly discussed.

关键词： bi-kappa electrons shock waves dust-ion-acoustic waves dusty plasma

Reliability analysis of extended generalized inverted exponential distribution with applications

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Journal of Systems Engineering and Electronics 2016年第2期27卷 484-492页

作者： Arwa m.Alshangiti m.Kayid m.Almulhim Department of Statistics and Operations Research College of Science King Saud University

A general version of the inverted exponential distribution is introduced, studied and analyzed. This generalization depends on the method of marshall-Olkin to extend a family of distributions. Some statistical and reliability properties of this family are studied. In addition, numerical estimation of the maximum likelihood estimate（mLE） parameters are discussed in details. As an application, some real data sets are analyzed and it is observed that the presented family provides a better fit than some other known distributions.

关键词： inverted exponential distribution reliability properties statistical properties maximum likelihood estimates applications

Numerical and experimental analysis of the closed-cell aluminium foam under low velocity impact using computerized tomography technique

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Acta mechanica Sinica 2019年第1期35卷 144-155,I0005页

作者： S.Talebi m.Sadighi m.m.Aghdam Department of mechanical Engineering Amirkabir University of TechnologyTehranIran

In the present work, the response of closed-cell aluminum foams under low-velocity impact has been studied numerically and experimentally. Computerized tomography is employed to access three-dimensional (3D) microstructure of the closed-cell aluminum foam. Effective parameters including foam density and the velocity of impactor on foam dynamic behavior are investigated. In order to show the validity and accuracy of results, some static experiments and low-velocity impact tests have been conducted. Results in dicate a remarkable agree me nt between the simulation and experimental data. moreover, the results show that by increasing the density of foam samples, the highest difference between numerical and experimenidi results for peak stress and absorbed energy are 35.9% and 6.9%, respectively, which is related to the highest density. For impact velocities ranging from 3.1 to 4.2 m/s, the maximum discrepancy in peak stress and absorbed energy occur at an inipact velocity of 3.1 m/s in which corresponding errors are 33.3% and 6.6%, respectively. For the impact velocity of 40 m/s, the highest increase in peak stress and absorbed energy are 667.9% and 370.3% associated with the density of 0.5 and 0.3 g/cm^3, respectively.

关键词： Finite element analysis Impact Aluminum foam Experimental analysis Energy absorption