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Standard heat treatment effects on TLP bonded IN-738LC superalloy using BNi-9 filler:An approach to make an ideal joint

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Transactions of Nonferrous Metals Society of China 2022年第1期32卷 192-205页

作者： Danesh AMIRI ata kamyabi-gol Seyed Abdolkarim SAJJADI Department of Materials Science and Engineering Engineering FacultyFerdowsi University of MashhadMashhadIran

The present research is focused on the effects of standard heat treatment on the microstructure and mechanical properties of diffusion brazed IN-738 LC *** distinct heat treatment cycles of full solution annealing,partial solution annealing,and aging treatment were applied to the bonded specimens,*** results reveal that bonding at 1120℃for 5 min leads to incomplete isothermal solidification and formation of eutectic phases including Ni-and Cr-rich borides in the joint *** the holding time to 45 min leads to the full isothermal solidification and formation of a nickel proeutectic solid-solution phase(γ)in the *** standard heat treatment of isothermally solidified and non-isothermally solidified specimens results in the complete elimination of the boride phases in the diffusion-affected zone and also the formation ofγ’precipitates in the isothermally solidified ***,discontinuously re-solidified products are observed in joint district in the non-isothermally solidified *** highest shear strength(~801 MPa)is achieved for isothermally solidified specimen after standard heat treatment;this strength is approximately 99%that of the substrate material.

关键词： IN738LC standard heat treatment diffusion brazing isothermal solidification γ’precipitates mechanical properties

First Record of Sexual Dimorphism in Toxasterid Echinoid Heteraster from the Early Cretaceous Deposits of the Kopet-Dagh Basin,NE Iran

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Acta Geologica Sinica(English Edition) 2023年第5期97卷 1318-1334页

作者： Hossein kamyabi SHADAN Morteza TAHERPOUR KHALIL-ABAD Exploration Directorate of the National Iranian Oil Company TehranIran Young Researchers and Elite Club Mashhad BranchIslamic Azad UniversityMashhadIran

Spatangoid echinoids belonging to Heteraster found in the Lower Cretaceous limestones and calcareous deposits of the Tirgan and Sarcheshmeh formations(Barremian-Aptian)in the Bahman jan-Bala stratigraphic section on the northern flank of the Borouj syncline,situated in the eastern Kopet-Dagh Basin,northeastern Iran are assessed as a sexually dimorphic *** dimorphism is a common feature in echinoids and,in this study of Heteraster renngarteni Poretzkaja,1961,sexual dimorphism has been detected for the first time in the family Toxasteridae.

关键词： invertebrate paleontology echinodermata Heteraster sexual dimorphism Barremian–Aptian Kopet-Dagh Iran

Voltammetric determination of stability constants of lead complexes with diallyl disulfide, dimethyl disulfide, and diallyl sulfide

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Chinese Chemical Letters 2016年第1期27卷 71-76页

作者： Mohammad Ali kamyabi Fatemeh Soleymani-Bonoti Saeed Zakavi Department of Chemistry University of Zanjan Department of Chemistry Institute for Advanced Studies in Basic Sciences

The complexation of Pb^（2＋）by diallyl disulfide（DADS）, dimethyl disulfide（DMDS） and diallyl sulfide（DAS）has been studied by differential pulse voltammetry. Stability constants,（log b）, of the 1：1（PbL） and 1：2（PbL_2） complexes, where L = ligand, were found to be in the range of ca. 3.8-4.2 and 9.4-10.2,respectively. Complex formation is accompanied with a significant decrease in the peak current and the shift of the Pb2＋/Pb half-wave potential to a higher one upon the addition of the sulfur containing ligands（L）. The formation of 1：1 and 1：2 complexes, i.e., PbL^（2＋）and PbL_2^（2＋）was observed in the case of the three ligands. The consecutive formation constants of labile lead complexes with DADS, DMDS, and DAS were determined at 298 K by the method of De Ford and Hume. Apparently due to the large size of the lead ion,steric hindrance caused by the greater steric bulk of DADS compared to that of DMDS have little or no effects on the formation constants, so that very similar values were obtained in the case of the two ligands. Also, the possible participation of C=C double bonds in coordination with the metal center in the case of DADS appears to compensate for the steric effects caused by the larger size of this ligand. In agreement with the Jorgensen principle of symbiosis, the second formation constants were found to be approximately six orders of magnitude greater than the first ones.

关键词： Garlic oil Organic sulfur compounds Pb^(2+)-DADS,DMDS,and DAS complexes Stability constant

Empirical study of magnetohydrodynamic effect on fluid flow in clayey porous media

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Petroleum Research 2024年第3期9卷 462-471页

作者： Farad kamyabi Arif Mammad Zade Center for Innovation and Research Baku Higher Oil SchoolBakuAzerbaijan Department of Oil&Gas Engineering Azerbaijan State Oil and Industry UniversityBakuAzerbaijan

Enhancing oil recovery from clayey reservoirs is a significant challenge in petroleum industry due to complex interactions between fluids and rock surfaces,particularly clay *** study presents the first empirical analysis of magnetic fields'impact on fluid flow in clayey porous *** core findings indicate that magnetic treatment of water increases oil recovery by an average of 15–30%in clayey media,with limited effectiveness in pure quartz *** experiments unraveled that improved recovery factor by magnetic treatment stem from both mitigated swelling and altered magnetic properties at clay surface;introducing 30%clay to porous medium decreased the recovery by 32%compared to pure quartz *** the clay to around 1000°C to reduce its swelling property improved the recovery by only 16%,suggesting magnetic treatment is not solely attributed to clay swelling *** ferromagnetic films at clay surface with HCl to produce non-magnetic FeCl_(3) resulted in a high recovery factor,similar to the clay-free ***,it was determined that a magnetic field intensity of 43760–51740 A/m is optimal for fluid displacement in clayey ***,the intensity of 47760 A/m increased recovery to 84.5%in a 30%clay medium,compared to 49.7%without ***,it was observed that the maximum flow rate was associated with zero potential difference across the medium,providing a faster method to determine the optimum magnetic field ***,the concept of‘Magnetic memory’was investigated,referring to the persistence of magnetic field's influence after its *** findings indicated that pressure build-up time stability lasted 10 days post-treatment,after which water behavior reverts,and clay swelling *** insight into the temporal dynamics of magnetic field application provides a deeper understanding of its long-term impacts on fluid flow in clayey reservoirs.

关键词： Water flooding Clayey porous media Magnetic treatment Clay swelling Nanotechnologies

Effects of the number of particles and coordination number on viscous-flow agglomerate sintering

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Particuology 2019年第2期17卷 76-83页

作者： Mohammadmahdi kamyabi Khashayar Saleh Rahmat Sotudeh-Gharebagh Reza Zarghami Multiphase Systems Research Laboratory School of Chemical Engineering College of Engineering University of Tehran Tehran 11155/4563 Iran Sorbonne University/Compiegne University of Technology EA 4297 Transformations Integrees de la Matiere renouvelable France

The process of sinteri ng of several particles in con tact via a viscous flow mecha nism was studied numerically using computational fluid dynamics. The volume of fluid technique within a finite volume method was used to simulate bridge formation between particles, as well as densification at different configurational states of the particles. The method was validated by comparing results for two-particle coalescence with the *** effect of the numberof particles on agglomerati on kin etics was studied by comparing bridge growth rate for systems having different numbers of particles in a chain. Although increasing the number of particles led to a decrease in the local bridge growth rate and to slower equilibration, there were no marked differences, when the overall volume of the system was considered. The effect of coordination number on the densification rate was directly studied by changing the number of particles in contact with a central *** the coordination nurnbec caused the overall rate of densificatio n to in crease, but delayed equilibration, analogous to steric effects. These findi ngs describe the con figurational state of agglomerates, typical of mesoscale caking. In a multi-scale study, they can be used to characterize caking at a bulk scale to partly address the lack of experimental data in this field.

关键词： Caking Agglomeration Sintering Viscous flow mechanism Volume of fluid Coordination number

Neural network based adaptive sliding mode control of uncertain nonlinear systems

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Journal of Systems Engineering and Electronics 2012年第1期23卷 119-128页

作者： Ghania Debbache Noureddine goléa Electrical Engineering Institute Oum El Bouaghi University 04000 Oum El Bouaghi Algeria

The purpose of this paper is the design of neural network-based adaptive sliding mode controller for uncertain unknown nonlinear systems. A special architecture adaptive neural network, with hyperbolic tangent activation functions, is used to emulate the equivalent and switching control terms of the classic sliding mode control （SMC）. Lyapunov stability theory is used to guarantee a uniform ultimate boundedness property for the tracking error, as well as of all other signals in the closed loop. In addition to keeping the stability and robustness properties of the SMC, the neural network-based adaptive sliding mode controller exhibits perfect rejection of faults arising during the system operating. Simulation studies are used to illustrate and clarify the theoretical results.

关键词： nonlinear system neural network sliding mode con- trol (SMC) adaptive control stability robustness.

Inclusive Multiple Models(IMM)for predicting groundwater levels and treating heterogeneity

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Geoscience Frontiers 2021年第2期12卷 713-724页

作者： Rahman Khatibi ata Allah Nadiri GTEV-ReX Limited SwindonUK Department of Earth Sciences Faculty of Natural ScienceUniversity of Tabriz29 Bahman BoulevardTabrizEast AzerbaijanIran Institute of Environment University of TabrizEast AzerbaijanIran

An explicit model management framework is introduced for predictive Groundwater Levels(GWL),particularly suitable to Observation Wells(OWs)with sparse and possibly heterogeneous *** framework implements Multiple Models(MM)under the architecture of organising them at levels,as follows:(i)Level 0:treat heterogeneity in the data,***-Organised Mapping(SOM)to classify the OWs;and decide on model structure,*** a grey box model to predict GWLs.(ii)Level 1:construct MMs,*** Fuzzy Logic(FL)and one Neurofuzzy(NF)models.(iii)Level 2:formulate strategies to combine the MM at Level 1,for which the paper uses Artificial Neural Networks(Strategy 1)and simple averaging(Strategy 2).Whilst the above model management strategy is novel,a critical view is presented,according to which modelling practices are:Inclusive Multiple Modelling(IMM)practices contrasted with existing practices,branded by the paper as Exclusionary Multiple Modelling(EMM).Scientific thinking over IMMs is captured as a framework with four dimensions:Model Reuse(MR),Hierarchical Recursion(HR),Elastic Learning Environment(ELE)and Goal Orientation(GO)and these together make the acronym of ***,IMM-RHEO is piloted in the aquifer of Tabriz Plain with sparse and possibly heterogeneous *** results provide some evidence that(i)IMM at two levels improves on the accuracy of individual models;and(ii)model combinations in IMM practices bring‘model-learning’into fashion for learning with the goal to explain baseline conditions and impacts of subsequent management changes.

关键词： Artificial intelligence Exclusionary multiple modelling(EMM) Groundwater level prediction Inclusive multiple modelling(IMM) Model management practices

Ion-acoustic waves with non-planar wavefronts

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Plasma Science and Technology 2024年第1期26卷 1-7页

作者： Shujaht BUKHARI Muhammad SHAHID ata-ur RAHMAN Department of Physics The University of Azad Jummu and KashmirMuzaffarabad 13100Azad Kashmir Department of Physics Women University of Azad Jammu&KashmirBagh 12500Pakistan Department of Physics Islamia College PeshawerPeshawar 25120Pakistan

The ion-acoustic(IA) mode exhibiting various orbital angular momentum(OAM) states is examined in a plasma with drifting *** constituent plasma species are modeled with a non-gyrotropic Maxwellian distribution and discussion of dispersion relation and growth rate of twisted IA waves under various conditions is *** the domain of kinetic model,the twisted IA waves are characterized by Laguerre-Gaussian(LG) solutions,where plasma distribution function and electric field are decomposed into axial and azimuthal *** plasma response function is obtained under paraxial approximations and investigated for threshold condition of instability growth rate with helical electric field *** impact of an extra electron specie on the instability is demonstrated through a comparison of twisted waves for single and double electron species.

关键词： instability twist parameter wave excitation orbital angular momentum threshold limit

A Model Predictive Control for Microgrids Considering Battery Aging

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Journal of Modern Power Systems and Clean Energy 2020年第2期8卷 296-304页

作者： Ugur Can Yilmaz Mustafa Erdem Sezgin Murat gol Department of Electrical and Electronics Engineering Middle East Technical UniversityAnkaraTurkey

The increasing number of distributed energy resources(DERs),advancing communication and computation technologies,and reliability concerns of the customers have caused an intense interest in the concept of *** DERs are the biggest motivation of the microgrids due to their intermittent generation characteristics,they constitute a risk for system *** storage systems(BSSs)stand as one of the most effective solutions for this reliability ***,the inappropriate use of BSS creates other operational problems in power *** order to deal with these concerns explicitly in microgrids,an optimized microgrid central controller(MGCC)is the key factor,which controls the realtime operation of a *** work proposes a model predictive control(MPC)based MGCC that will provide optimal control of the microgrid,considering economic and operational *** proposed system will minimize the energy cost of the microgrid by utilizing mixed-integer linear programming(MILP)assuming the presence of DERs and BSS as well as the bi-directional grid ***,the aging effect of BSS will be considered in the proposed optimization problem which will provide an up-to-date system *** proposed method is evaluated using real load and photovoltaic(PV)generation data.

关键词： Microgrid optimization battery storage model predictive control mixed-integer linear programming