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Single ionization of helium atoms by energetic fully stripped carbon ions

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Chinese Physics B 2015年第10期24卷 154-159页

作者： Ebrahim Ghanbari-Adivi Sadjad eskandari Department of Physics Faculty of SciencesUniversity of Isfahan

A four-body distorted wave approximation is presented for theoretical investigations of the single ionization of groundstate helium atoms by fully stripped carbon ions at impact energies of 2 MeV/amu and 100 MeV/amu. The nine-dimensional integrals for the partial quantum-mechanical transition amplitudes of the specified reaction are reduced to some analytical expressions or one-dimensional integrals over real variables. Fully differential cross sections（FDCSs） are calculated and compared with their experimental values as well as the results obtained from other theories. Despite the simplicity and quickness of the proposed quadrature, the comparison shows that the obtained results are in reasonable agreement with the experiment and are compatible with those of other complicated theories.

关键词： ion-impact ionization four-body distorted wave approximation transition amplitude fully differ- ential cross sections

Optimizing the compressive strength of concrete containing micro-silica, nano-silica, and polypropylene fibers using extreme vertices mixture design

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Frontiers of Structural and Civil Engineering 2019年第4期13卷 821-830页

作者： Fatemeh ZAHIRI Hamid eskandari-NADDAF Department of Civil Engineering Hakim Sabzevari University Sabzevar *** Iran

Many studies have evaluated the effects of additives such as nano-silica (NS), micro-silica (MS) and polymer fibers on optimizing the mechanical properties of concrete, such as compressive strength. Nowadays, with progress in cement industry provides, it has become possible to produce cement type I with strength classes of 32.5, 42.5, and 52.5 MPa. On the one hand, the microstructure of cement has changed, and modified by NS, MS, and polymers;therefore it is very important to determine the optimal percentage of each additives for those CSCs. In this study, 12 mix designs containing different percentages of MS, NS, and polymer fibers in three cement strength classes(CSCs)(32.5, 42.5, and 52.5 MPa) were designed and constructed based on the mixture method. Results indicated the sensitivity of each CSCs can be different on the NS or MS in compressive strength of concrete. Consequently, strength classes have a significant effect on the amount of MS and NS in mix design of concrete. While, polymer fibers don’t have significant effect in compressive strength considering CSCs.

关键词： mixture method compressive strength nano-silica micro-silica polypropylene fibers

The ITZ microstructure,thickness,porosity and its relation with compressive and flexural strength of cement mortar;influence of cement fineness and water/cement ratio

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Frontiers of Structural and Civil Engineering 2022年第2期16卷 191-201页

作者： Tahereh KOROUZHDEH Hamid eskandari-NADDAF Ramin KAZEMI Department of Civil Engineering Hakim Sabzevari UniversitySabzevar***Iran

A new insight into the interfacial transition zone(ITZ)in cement mortar specimens(CMSs)that is influenced by cement fineness is *** importance of cement fineness in ITZ characterizations such as morphology and thickness is elucidated by backscattered electron images and by consequences to the compressive(Fc)and flexural strength(Ff),and porosity at various water/cement *** findings indicate that by increasing the cement fineness the calcium silicate hydrate formation in the ITZ is favored and that this can refine the pore structures and create a denser and more homogeneous *** increasing cement fineness by about 25%of,the ITZ thickness of CMSs was reduced by about 30%and Fc was increased by 7%–52%and Ff by 19%–40%.These findings illustrate that the influence of ITZ features on the mechanical strength of CMSs is mostly related to the cement fineness and ITZ microstructure.

关键词： cement fineness interfacial transition zone compressive and flexural strength

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Electron correlation in fast ion-impact single ionization of helium atoms

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Chinese Physics B 2015年第1期24卷 240-246页

作者： E.Ghanbari-Adivi S.eskandari Department of Physics and Isfahan Quantum Optics Group (IQOG) Faculty of Science University of Isfahan Isfahan 81746-73441 Iran

A four-body distorted-wave approximation is applied for theoretical analysis of the fully differential cross sections（FDCS） for proton-impact single ionization of helium atoms in their ground states. The nine-dimensional integrals for the partial amplitudes are analytically reduced to closed-form expressions or some one-dimensional integrals which can be easily calculated numerically. Calculations are performed in the scattering and perpendicular planes. The influence of the target static electron correlations on the process is investigated using a number of different bound-state wave functions for the ground state of the helium targets. An illustrative computation is performed for 75-ke V proton–helium collisions and the obtained results are compared with experimental data and other theoretical predictions. Although for small momentum transfers, the comparison shows a reasonable agreement with experiments in the scattering and perpendicular planes, some significant discrepancies are still present at large momentum transfers in these planes. However, our results are compatible and for some cases, better than those of the other sophisticated calculations.

关键词： single ionization four-body collision distorted-wave approximation electron correlation

Evaluation of Four Coals for Blast Furnace Pulverized Coal Injection

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Journal of Iron and Steel Research International 2010年第3期17卷 8-12,20页

作者： Sh Raygan H Abdizadeh A eskandari Rizi School of Metallurgy and Materials Engineering University of Tehran

One of the effective methods of reducing coke consumption is pulverized coal injection. The most important problems encountered in this method are reduced permeability, unburned and high ash content. To select the best coal for injection, suitable tests can be used. Therefore, experiments such as proximate and ultimate analysis, Rock- Eval and combustion tests were performed on four kinds of coals from different mines, including Sarakhs, Sangrood, Karmozd, and Tabas. The results of proximate and ultimate analysis indicated that although the sulfur content and ash content of selected coals were a little high, they were suitable for coal injection. The results of combustion experiments and Rock-Eval tests showed that Karmozd coal was the best one to be injected into blast furnace. The result indicated that the mixing of coals could improve the combustion properties of pulverized coals.

关键词： pulverized coal blast furnace non-coking coal

Combined Computational and Experimental Study on the Adsorption and Inhibition Effects of N_2O_2 Schiff Base on the Corrosion of API 5L Grade B Steel in 1 mol/L HCl

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Journal of Materials Science & Technology 2014年第3期30卷 239-252页

作者： Hojat Jafari Iman Danaee Hadi eskandari Mehdi RashvandAvei Abadan Faculty of Petroleum Engineering Petroleum University of Technology Department of Chemistry K.N.Toosi University of Technology

The electrochemical behavior of low carbon steel （API 5L grade B） in 1 mol/L HCI solution with different concentrations of N,Nr-bis（4-formylphenol）-trimethylenediamine Schiff base was studied by electrochemical techniques and density functional theory analysis. The inhibition efficiency was found to increase with increasing inhibitor concentration and decreased with increasing temperature. The high inhibition efficiency was attributed to the blocking of active sites by adsorption of inhibitor molecules on the steel surface. Thermodynamic parameters for the adsorption and activation processes were determined. Galvanostatic polarization data indicated that Schiff base act as a mixed-type inhibitor and the adsorption isotherm obeyed the Langmuir adsorption isotherm. Results obtained from quantum chemical studies show excellent correlations between the quantum chemical parameters and the experimental inhibition efficiencies using density functional theory at the B3LYP/6-31G（d,p） and B3LYP/3-21G basis set levels and ab initio calculations using HF/6-31G（d,p） and HF/3-21G methods.

关键词： Corrosion Inhibitor Impedance Density functional theory Atomic force microscopy

Nonlinear dynamics of a three-dimensional discrete-time delay neural network

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International Journal of Biomathematics 2024年第6期17卷 161-175页

作者： Parvaiz Ahmad Naik Zohreh eskandari Department of Mathematics and Computer Science Youjiang Medical University for Nationalities Baise Guangri P.R.China Department of Mathematics Faculty of Science FasaUniversityFasaIran

This paper examines a three-dimensional delayed discrete neural network model analytically and numerically to determine the existence of different types of bifurcations of the involved fixed *** model exhibits different bifurcations such as pitchforks,fips,Neimark-Sackers,and *** critical coefficients are used to determine the structure of each *** curves are calculated and plotted for each bifurcation when the parameters are ***,these bifurcations are theoretically analyzed and numerically *** the obtained results,we observed that by drawing the curves associated with each bifurcation,the numerical simulations are consistent with the analytical results.

关键词： Hopfield neural network time delay stability bifurcation numerical continuation

Effects of salt and nitrogen on physiological indices and carbon isotope discrimination of wheat cultivars in the northeast of Iran

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Journal of Integrative Agriculture 2020年第3期19卷 656-667页

作者： Azam BORZOUEI MirAhmad MOUSAVI SHALMANI Ali eskandari Nuclear Agriculture Research School Nuclear Science and Technology Research Institute(NSTRI)

In order to study the effects of different levels of salt stress and nitrogen(N) on physiological mechanisms,carbon isotope discrimination(△13C),and yield of two wheat cultivars(cv.),a two-year field experiment was carried out during *** treatments included three levels of salt stress(1.3,5.2,and 10.5 dS m^-1),three levels of N(50,100,and 150 kg N ha-1),and two wheat cultivars,Bam and *** salt stress,N application(100 and 150 kg N ha^-1) produced a significant effect on both cultivars with respect to physiological traits,i.e.,net photosynthetic rate(Pn),stomatal conductance(gs),chlorophyll index(Cl),Na^+/K^+ ratio as well as the grain yield(GY).The salt-tolerant and-sensitive cultivars exhibited the maximum values of physio-biochemical and yield attributes at 100 and 150 kg N ha-1,*** results of △13C showed a significant difference(P<0.001) between wheat cultivars under the control and salt *** to our result,salt-tolerant cultivar Bam seems to be more efficient in terms of higher GY,Pn,gs,Cl,and lower Na^+/K^+ ratio as well as higher △13C as compared with salt-sensitive cultivar Toos,under salt ***,a significant positive correlation that observed between △13C and GY,indicated that △13C may be an effective index for indirect selection of yield potential in wheat under irrigation regimes with saline water.

关键词： net photosynthetic rate stomatal conductance chlorophyll index carbon isotope discrimination

Assessment of fracture process in forta and polypropylene fiber-reinforced concrete using experimental analysis and digital image correlation

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Frontiers of Structural and Civil Engineering 2022年第12期16卷 1633-1652页

作者： Seyed Hamid KALALI Hamid eskandari-NADDAF Seyed Ali EMAMIAN Department of Civil Engineering Hakim Sabzevari UniversitySabzevar ***Iran

This paper aims to characterize the evolution of the fracture process and the cracking behavior in fortaferro(FF)and polypropylene(PP)fiber-reinforced concrete under the uniaxial compressive loading using experimental analysis and digital image correlation(DIC)on the surface *** this purpose,6 mix designs,including two FF volume fractions of 0.10%,and 0.20%and three PP volume fractions of 0.20%,0.30%,and 0.40%,in addition to a control mix were evaluated according to compressive strength,modulus of elasticity,toughness index,and stress–strain *** influence of fibers on the microstructural texture of specimens was analyzed by scanning electron microscope(SEM)*** show that FF fiber-reinforced concrete specimens demonstrated increased ductility and strength compared to PP *** results revealed that the major crack and fracture appeared at the peak load of the control specimen due to brittleness and sudden gain of large lateral strain,while a gradual increase in micro-crack quantity at 75%of peak load was observed in the fiber specimens,which thenbegan to connect with each other up to the final *** accuracy of the results supports DIC as a reliable alternative for the characterization of the fracture process in fiber-reinforced concrete.

关键词： fiber-reinforced concrete forta-ferro and polypropylene fiber fracture process cracking behavior digital image correlation

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