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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

Characterization and corrosion behavior of Al-Co-rare earth(Ce-La)amorphous alloy

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Journal of Rare Earths 2023年第5期41卷 771-779,I0006页

作者： seyed ali Mousavi Sayed Hamid Hashemi ali Ashrafi reza Shoja Razavi Seyyed Mehdi Ghazi Mirsaeed Faculty of Materials and Manufacturing Technologies Malek Ashtar University of TechnologyTehran167885611Iran Department of Materials Engineering Malek Ashtar University of TechnologyIsfahanShahin-shahrIran Department of Materials Engineering Isfahan University of TechnologyIsfahan***Iran

A new Al-based amorphous alloy with excellent corrosion resistance and high thermal stability was produced in the Al-Co-RE(Ce-La)*** this regard,two different amorphous-nanocrystalline ribbons:Al_(87.6)-Co_(6.4)-Ce_(3.8-)La_(2.2)(M_(1))and Al_(82.3)-Co_(10.1)-Ce_(4.8)-La_(2.8)(M_(2))were prepared using melt *** results reveal the supercooled liquid region(ATx)of 218℃which shows that the M2alloy has higher thermal stability in comparison to the *** M2ribbons present the superior corrosion resistance because of the formation of amorphous *** icorr,Ecorr,Epit,and Epit-Ecorrvalues of fully amorphous Al-Co-Ce-La metallic ribbons have a better trend of anti-corrosion performance compared to other crystalline and amorphous aluminum alloys.

关键词： Amorphous alloys Melt-spinning Rare earth metal Corrosion behavior

Fault ride-through capability improvement in a DFIG-based wind turbine using modified ADRC

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Protection and Control of Modern Power Systems 2022年第1期7卷 751-787页

作者： seyed reza Mosayyebi seyed Hamid Shahalami Hamed Mojallali Electrical Engineering Department Faculty of EngineeringUniversity of GuilanRashtIran

In this paper,an overview of several strategies for fault ride-through(FRT)capability improvement of a doubly-fed induction generator(DFIG)-based wind turbine is *** and parameter variations have adverse effects on the performance of these *** is desirable to use a control method that is robust to such *** disturbance rejection control(ADRC)is one of the most common methods for eliminating the effects of *** improve the performance of the conventional ADRC,a modified ADRC is introduced that is more robust to disturbances and offers better *** non-derivability of the fal function used in the conventional ADRC degrades its efficiency,so the modified ADRC uses alternative functions that are derivable at all points,i.e.,the odd trigonometric and hyperbolic functions(arcsinh,arctan,and tanh).To improve the effciency of the proposed ADRC,fuzzy logic and fractional-order functions are used *** fuzzy fractional-order ADRC(FFOADRC),all disturbances are evaluated using a nonlinear fractional-order extended state observer(NFESO).The performance of the suggested structure is investigated in MATLAB/*** simulation results show that during disturbances such as network voltage sag/swell,using the modified ADRCs leads to smaller fluctuations in stator flux amplitude and DC-link voltage,lower variations in DFIG velocity,and lower total harmonic distortion(THD)of the stator *** demonstrates the superiority over conventional ADRC and a proportional-integral(PI)***,by chang-ing the crowbar resistance and using the modified ADRCs,the peak values of the waveforms(torque and currents)can be controlled at the moment of fault occurrence with no significant distortion.

关键词： Doubly-fed induction generator(DFIG) Auto disturbance rejection control(ADRC) Fault ride-through(FRT) Wind turbine Nonlinear fractional-order extended state observer(NFESO)

New approach to solving master equations of density operator for the Jaynes Cummings model with cavity damping

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Chinese Physics B 2014年第9期23卷 65-70页

作者： seyed Mahmoud Ashrafi Mohammad reza Bazrafkan Physics Department Faculty of ScienceI.K.I.University

By introducing thermo-entangled state representation Ⅰη〉, which can map master equations of density operator in quantum statistics as state-vector evolution equations, and using ＂dissipative interaction picture＂ we solve the master equation of Jaynes-Cummings model with cavity damping. In addition we derive the Wigner function for density operator when the atom is initially in the up state Ⅰ↑〉 and the cavity mode is in coherent state.

关键词： Jaynes-Cummings model entangled state representation master equations

Comparison of dry reforming of methane in low temperature hybrid plasma-catalytic corona with thermal catalytic reactor over Ni/γ-Al_2O_3

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Journal of Natural Gas Chemistry 2012年第4期21卷 466-475页

作者： Amin Aziznia Hamid reza Bozorgzadeh Naser seyed-Matin Morteza Baghalha ali Mohamadalizadeh Department of Chemical & Petroleum Engineering Sharif University of TechnologyAzadi St.Tehran11365-9465Iran Plasma Research Laboratory Research Institute of Petroleum Industry(RIPI)14665-1998TehranIran Gas Research Division Research Institute of Petroleum Industry(RIPI)14665-1998TehranIran

In the current study, the hybrid effect of a corona discharge and γ-alumina supported Ni catalysts in CO2 reforming of methane is investigated. The study includes both purely catalytic operation in the temperature range of 923-1023 K, and hybrid catalytic-plasma operation of DC corona discharge reactor at room temperature and ambient pressure. The effect of feed flow rate, discharge power and Ni/γ-Al2O3 catalysts are studied. When CH4/CO2 ratio in the feed is 1/2, the syngas of low Ha/CO ratio at about 0.56 is obtained, which is a potential feedstock for synthesis of liquid hydrocarbons. Although Ni catalyst is only active above 573 K, presence of Ni catalysts in the cold corona plasma reactor （T≤523 K） shows promising increase in the conversions of methane and carbon dioxide. When Ni catalysts are used in the plasma reaction, H2/CO ratios in the products are slightly modified, selectivity to CO increases whereas fewer by-products such as hydrocarbons and oxygenates are formed.

关键词： dry reforming of methane synthesis gas hybrid catalyst plasma Ni/γ-Al2O3 discharge power

On the Nonorientable Genus of the Generalized Unit and Unitary Cayley Graphs of a Commutative Ring

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Algebra Colloquium 2022年第1期29卷 167-180页

作者： Mahdi reza Khorsandi seyed reza Musawi Faculty of Mathematical Sciences Shahrood University of Technology P.O.Box 36199-95161ShahroodIran

Let R be a commutative ring and U(R)the multiplicative group of unit elements of *** 2012,Khashyarmanesh et *** the generalized unit and unitary Cayley graph,T(R,G,S),corresponding to a multiplicative subgroup G of U(R)and a nonempty subset S of G with S^(-1)={s^(-1)|s∈S}■S,asthegraphwithvertexsetR and two distinct vertices x and y being adjacent if and only if there exists s∈S such that x+sy∈*** this paper,we characterize all Artinian rings R for which T(R,U(R),S)is *** leads us to determine all Artinian rings whose unit graphs,unitary Cayley graphs and co-maximal graphs are *** addition,we prove that for an Artinian ring R for which T(R,U(R),S)has finite nonorientable genus,R must be a finite ***,it is proved that for a given positive integer k,the number of finite rings R for which T(R,U(R),S)has nonorientable genus k is finite.

关键词： unit graph unitary Cayley graph co-maximal graph projective graph nonorientable genus

Synthesis and Crystal Structure of N-(2-(1,3,4-oxadiazol-2-yl)phenyl)-2,3-dimethylaniline

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Chinese Journal of Structural Chemistry 2014年第3期33卷 407-414页

作者： ali Souldozi seyed Hamid reza Shojaei ali Ramazani Katarzyna ?lepokura Tadeusz Lis Department of Chemistry Urmia Branch Islamic Azad University Department of Physics Urmia Branch Islamic Azad University Department of Chemistry Zanjan Branch Islamic Azad University Faculty of Chemistry University of Wroc?aw 14 Joliot-Curie St. 50-383 Wroc?aw Poland

The title compound, N-（2-（1,3,4-oxadiazol-2-yl）phenyl）-2,3-dimethylaniline, was synthesized and studied by single-crystal X-ray diffraction method. The structure of the product was confirmed by IR, ^1H- and ^13C-NMR spectroscopy, elemental analysis and mass spectrometry. These experimental studies were supported by theoretical optimizations.

关键词： single-crystal X-ray structure 1,3,4-oxadiazoles N-(2-(1,3,4-oxadiazol-2- yl)phenyl)-2,3-dimethylaniline (N-isocyanimino)triphenylphosphorane

Synthesis and Crystal Structure of Methyl 2-(Diphenylamino)-4-phenyl-1,3-thiazole-5-carboxylate

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Chinese Journal of Structural Chemistry 2013年第1期32卷 82-88页

作者： ali Souldozi seyed Hamid reza Shojaei ali Ramazani Katarzyna lepokura Tadeusz Lis Department of Chemistry Urmia Branch Islamic Azad University P. O. Box 969 Urmia Iran Department of Physics Urmia Branch Islamic Azad University P. O. Box 969 Urmia Iran Department of Chemistry Zanjan Branch Islamic Azad University P. O. Box 49195-467 Zanjan Iran Faculty of Chemistry University of Wroclaw 14 Joliot-Curie St. 50-383 Wroclaw Poland

The title compound, methyl 2-（diphenylamino）-4-phenyl-1,3-thiazole-5-carboxylate, was synthesized and studied by single-crystal X-ray diffraction method. The structure of the product was confirmed by IR, 1H- and 13C-NMR spectroscopy and elemental analysis. These experimental studies were supported by quantum mechanical calculations. The structure was solved in monoclinic, space group P21/c with a = 9.573（3）, b = 19.533（7）, c = 9.876（3）, β = 92.35（4）°, V = 1845.2（10）3, T = 85（2） K, Z = 4, R = 0.040 and wR = 0.089 for 6424 observed reflections with I2σ（I）.

关键词： single-crystal X-ray structure multi-component reaction methyl 2-(diphenylamino)-4-phenyl-1 3-thiazole-5-carboxylate benzoyl isothiocyanate diphenylamine dimethyl acetylenedicarboxylate

A novel control strategy based on a look-up table for optimal operation of MTDC systems in post-contingency conditions

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Protection and Control of Modern Power Systems 2022年第1期7卷 40-50页

作者： seyed Mohsen Alavi reza Ghazi Department of Electrical Engineering Ferdowsi University of MashhadMashhadIran

Multi terminal VSC-HVDC systems are a promising solution to the problem of connecting offshore wind farms to AC *** power sharing and appropriate control of DC-link voltages are essential and must be maintained dur-ing the operation of VSC-MTDC systems,particularly in post-contingency *** traditional droop control methods cannot satisfy these requirements,and accordingly,this paper proposes a novel centralized control strategy based on a look-up table to ensure optimal power sharing and minimum DC voltage deviation immediately during post-contingency conditions by considering converter *** also reduces destructive effects(e.g.,frequency devia-tion)on onshore AC grids and guarantees the stable operation of the entire MTDC *** proposed look-up table is an array of data that relates operating conditions to optimal droop coefficients and is determined according to N-1 contingency analysis and a linearized system *** constraints and contingencies such as wind power changes,converter outage,and DC line disconnection are considered in its formation *** performed on a 4-terminal VSC-MTDC system in the MATLAB-Simulink environment validate the effectiveness and superiority of the proposed control strategy.

关键词： Optimal power sharing DC voltage deviation Adaptive droop control Multi-terminal HVDC(MTDC) Voltage source converter(VSC)