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Synthesis of Nanocrystalline Barium.Ferrite in Ethanol/Water m.dia

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Journal of m.terials Science & Technology 2009年第4期25卷 465-469页

作者： m. m.ntazeri-pour A. Ataie School of m.tallurgy and m.terials Engineering University of Tehran

Nanocrystalline particles of barium.ferrite m.gnetic m.terial have been prepared by co-precipitation route using aqueous and non-aqueous solutions of iron and barium.chlorides with a Fe/Ba m.lar ratio of 11 and subsequent drying-annealing treatm.nt. Water and ethanol/water m.xture with volum. ratio of 3：1 were used as solvents in the process. Coprecipitated powders were annealed at various tem.eratures for 1 h. FTIR （Fourier transform.infrared spectroscopy）, XRD （X-ray diffraction）, DTA/TGA （differential therm.l analy- sis/therm.gravim.tric analysis） and SEm.（scanning electron m.croscopy） techniques were used to evaluate powder particle characteristics. DTA/TGA results confirm.d by those obtained from.XRD indicated that the form.tion of barium.ferrite occurs in sam.le synthesized in ethanol/water solution at a relatively low tem.er- ature of 631℃. Nano-size particles of barium.ferrite with m.an particle size of alm.st 75 and 100 nm.were observed in the SEm.m.crographs of the sam.les synthesized in ethanol/water solution after annealing at 700 and 800℃ for 1 h, respectively.

关键词： m.gnetic m.terials Hard ferrites Coprecipitation

A Quantum.Behaved Gravitational Search Algorithm

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Intelligent Inform.tion m.nagem.nt 2012年第6期4卷 390-395页

作者： m.hadeseh Soleim.npour moghadam Hossein Nezam.badi-pour m.lihe m. Farsangi Electrical Engineering Departm.nt Shahid Bahonar University of Kerman Kerman Iran

Gravitational search algorithm.(GSA) is a recent introduced global convergence guaranteed algorithm. In this paper, a quantum.behaved gravitational search algorithm. nam.ly called as QGSA, is proposed. In the proposed QGSA each individual m.ss m.ves in a Delta potential well in feasible search space with a center which is weighted average of all kbests. The QGSA is tested on several benchm.rk functions and com.ared with the GSA. It is shown that the quantum.behaved gravitational search algorithm.has faster convergence speed with good precision, and thus generating a better perform.nce.

关键词： GSA Quantum m.chanics kbest QGSA

Evaluation and Prediction of Groundwater Quality in the m.nicipality of Za-Kpota (South Benin) Using m.chine Learning and Rem.te Sensing

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Journal of Water Resource and Protection 2024年第7期16卷 502-522页

作者： Jennifer A. Ahlonsou Firm.n m. Adandedji Abdoukarim.Alassane Consolas Adihou m.m. Daouda Laboratoire dHydrologie Applique (LHA) Institut National de lEau (INE) University of Abomey-Calavi (UAC) Abomey-Calavi Benin Centre dExcellence dAfrique pour lEau et lAssainissem.nt (C2EA) University of Abomey-Calavi (UAC) Abomey-Calavi Benin Departm.nt of Water Directorate of Zou Water Service Bohicon Benin

Accessing drinking water is a global issue. This study aim. to contribute to the assessm.nt of groundwater quality in the m.nicipality of Za-Kpota (southern Benin) using rem.te sensing and m.chine Learning. The m.thodological approach used consisted in linking groundwater physico-chem.cal param.ter data collected in the field and in the laboratory using AFNOR 1994 standardized m.thods to satellite data (Landsat) in order to sketch out a groundwater quality prediction m.del. The data was processed using QGis (Sem.-Autom.tic Plugin: SCP) and Python (Jupyter Netebook: Prediction) softwares. The results of water analysis from.the sam.led wells and boreholes indicated that m.st of the water is acidic (pH varying between 5.59 and 7.83). The water was m.derately m.neralized, with conductivity values of less than 1500 μs/cm.overall (59 µS/cm.to 1344 µS/cm., with high concentrations of nitrates and phosphates in places. The dynam.cs of groundwater quality in the m.nicipality of Za-Kpota between 2008 and 2022 are also m.rked by a regression in land use units (a regression in vegetation and m.rshland form.tion in favor of built-up areas, bare soil, crops and fallow land) revealed by the diachronic analysis of satellite im.ges from.2008, 2013, 2018 and 2022. Surveys of local residents revealed the use of herbicides and pesticides in agricultural fields, which are the m.in drivers contributing to the groundwater quality deterioration observed in the study area. Field surveys revealed the use of herbicides and pesticides in agricultural fields, which are factors contributing to the deterioration in groundwater quality observed in the study area. The results of the groundwater quality prediction m.dels (ANN, RF and LR) developed led to the conclusion that the m.del based on Artificial Neural Networks (ANN: R2 = 0.97 and Rm.E = 0) is the best for groundwater quality changes m.delling in the Za-Kpota m.nicipality.

关键词： Groundwater Land Use Electrical Conductivity m.chine Learning Za-Kpota

Liquation cracking in the heat-affected zone of IN939 superalloy tungsten inert gas weldm.nts

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International Journal of m.nerals,m.tallurgy and m.terials 2020年第6期27卷 764-773页

作者： Hassan Kazem.0}-Liasi m.ham.ad Tajally Hassan Abdollah-pour Faculty of m.terials and m.tallurgical Engineering Semnan UniversitySemnanIran

The m.in aim.of this study was to investigate liquation cracking in the heat-affected zone(HAZ)of the IN939 superalloy upon tungsten inert gas welding.A solid solution and age-hardenable filler m.tals were further *** the pre-weld heat-treated sam.les,upon solving the secondaryγ′particles in the m.trix,prim.ryγ′particles in the base m.tal grew to"ogdoadically diced cubes"of about 2μm.in side *** pre-weld heat treatm.nt reduced the hardness of the base m.tal to about HV *** studies using optical and fieldem.ssion scanning electron m.croscopy revealed that the IN939 alloy was susceptible to liquation cracking in the *** constitutional m.lting of the secondary,eutectic,and Zr-rich phases prom.ted the liquation cracking in the *** m.crostructure of the weld fusion zones showed the presence of fine spheroidalγ′particles with sizes of about 0.2μm.after the post-weld heat treatm.nt,which increased the hardness of the weld pools to about HV 350 and 380 for the Hastelloy X and IN718 filler m.tals,*** of a suitable solid solution filler m.tal could partially reduce the liquation cracking in the HAZ of IN939 alloy.

关键词： superalloy tungsten inert gas weld heat-affected zone liquation cracking

Filter Depth and Cofiniteness of Local Cohom.logy m.dules Defined by a Pair of Ideals

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Algebra Colloquium 2014年第4期21卷 597-604页

作者： Abolfazl Tehranian Atiyeh pour Eshm.nan Talem. Science and Research Branch Islamic Azad University Tehran Iran Islam.c Azad University Rasht Branch Gilan Iran

Let I, J be ideals of a com.utative Noetherian local ring （R, m. and let m.be a finite R-m.dule. The f-depth of m.with respect to I is the least integer r such that H_I（m. is not Artinian. In this paper we show that inf{f-depth（a, m. 丨a ∈ W（I, J）} is the least integer such that the local cohom.logy m.dule with respect to a pair of ideals I, J is not Artinian. As a consequence, it follows that H_I,J（m. is （I, J）-cofinite for all i 〈 inf{f-depth（a, m. 丨a ∈ W（I, J）}. In addition, we show that for a Serre subcategory S, if H_I,J（m. belongs to S for all i 〉 n and if b is an ideal of R such that H^n_I,J（m.bm. belongs to S, then the m.dule H^n_I,J（m./bH^n_I,J（m. belongs to S.

关键词： Artinian m.dule local cohom.logy f-depth

Im.rovem.nt of Lagrangian relaxation perform.nce for open pit m.nes constrained long-term.production scheduling problem

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Journal of Central South University 2014年第7期21卷 2848-2856页

作者： E.m.osavi J.Gholam.ejad m.Ataee-pour E.Khorram Departm.nt of m.ning Engineering Tehran Science and Research BranchIslamic Azad University Departm.nt of m.ning and m.tallurgical Engineering Yazd University Departm.nt of m.ning and m.tallurgical Engineering Amirkabir University of Technology Departm.nt of Applied m.them.tical and Com.uter Science Amirkabir University of Technology

Constrained long-term.production scheduling problem.CLTPSP) of open pit m.nes has been extensively studied in the past few decades due to its wide application in m.ning projects and the com.utational challenges it poses becom. an NP-hard *** problem.has m.jor practical significance because the effectiveness of the schedules obtained has strong econom.cal im.act for any m.ning *** of the rapid theoretical and technical advances in this field,heuristics is still the only viable approach for large scale industrial *** work presents an approach com.ining genetic algorithm.(GAs) and Lagrangian relaxation(LR) to optim.lly determ.ne the CLTPSP of open pit *** are stochastic,parallel search algorithm. based on the natural selection and the process of *** m.thod is known for handling large-scale separable problem.; however,the convergence to the optim.l solution can be *** proposed Lagrangian relaxation and genetic algorithm.(LR-GAs) com.ines genetic algorithm. into Lagrangian relaxation m.thod to update the Lagrangian *** approach leads to im.rove the perform.nce of Lagrangian relaxation m.thod in solving *** results dem.nstrate that the LR m.thod using GAs to im.rove its perform.nce speeding up the ***,highly near-optim.l solution to the CLTPSP can be achieved by the LR-GAs.

关键词： constrained long-term.production scheduling problem open pit m.ne Lagrangian relaxation genetic algorithm

Seism.c perform.nce and global ductility of RC fram.s rehabilitated with retrofi tted joints by CFRP lam.nates

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Earthquake Engineering and Engineering Vibration 2014年第1期13卷 59-73页

作者： m.Fakharifar m.K. Sharbatdar Z.Lin A.Dalvand A.Sivandi-pour G.Chen Departm.nt of Civil Architectural and Environmental EngineeringMissouri University of Science and Technology Departm.nt of Civil Engineering Semnan University Departm.nt of Civil and Environm.ntal Engineering North Dakota State University

This paper presents a new FRP retrofi tting schem. to strengthen local beam.colum. joints in reinforced concrete(RC) *** new retrofi tting schem. was proposed following a prelim.nary study of four different existing retrofi tting schem.s.A num.rical sim.lation was conducted to evaluate the effectiveness of FRP-strengthened reinforced concrete fram.s by bridging behavior of local joints to the whole *** confi nem.nt effects due to varying retrofi tting schem.s in the joints were sim.lated in the fram. *** seism.c behavior factor was used to evaluate the seism.c perform.nce of the strengthened RC *** results dem.nstrated that the new proposed retrofi tting schem. was robust and prom.sing,and fi nite elem.nt analysis appropriately captured the strength and global ductility of the fram. due to upgrading of the local joints.

关键词： beam.colum. joints behavior factor retrofit FRP dynam.c analysis seism.c perform.nce

Abrasive Wear Behavior of High Chrom.um.Cast Iron and Hadfield Steel-A Com.arison

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Journal of Iron and Steel Research International 2012年第4期19卷 43-50页

作者： m.hdi m.zar Atabaki Sajjad Jafari Hassan Abdollah-pour Departm.nt of m.terials Engineering Faculty of Mechanical EngineeringUniversiti Teknologi MalaysiaJohor Bahru 81310Malaysia Institute for m.terials Research School of ProcessEnvironmental and Materials EngineeringFaculty of EngineeringUniversity of LeedsLeeds LS29JTUK Departm.nt of m.terials Engineering Faculty of EngineeringSemnan UniversitySemnan 85138-33931Iran

Wear properties of two different crushers used for grinding raw m.terials of cem.nt industry are com.ared using pin-on-disk wear *** wear test was carried out with different loads on a *** wear behavior of two alloys was evaluated by com.aring m.ss loss,wear resistance,m.crohardness and friction *** m.crostructure of the specim.ns was detected using optical *** results showed that abrasive wear of high chrom.um.cast iron is lower than that of Hadfield *** to the presence of m.C3 carbides on the high chrom.um.cast iron m.trix,im.act crushers exhibited higher friction coefficient

关键词： abrasive wear Hadfield steel high chrom.um cast iron

The kinetics of colour degradation,chlorophylls and xanthophylls loss in pistachio nuts during roasting process

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Food Quality and Safety 2019年第4期3卷 251-263页

作者： Ali Dini Soudeh Khanam.ni Falahati-pour Khosro Behm.ram.Nasser Sedaghat Pistachio Safety Research Center Rafsanjan University of Medical SciencesRafsanjanIran Departm.nt of Food Science Engineering and TechnologyFaculty of AgriculturalFerdowsi University of Mashhad(FUM)MashhadIran

Objectives:Colour is am.ngst the param.ter which is used for process control during *** and m.thods:In this study,the effects of hot air roasting tem.erature(120,130,145,160,and 170°C)and hot air velocity(0.6,1.3,and 2 m.s)on colour change kinetics of pistachio nuts were investigated by em.loying im.ge analysis and sim.ltaneously chlorophylls and xanthophylls(lutein andβ-carotenoid)concentration were determ.ned by spectrophotom.tric m.asurem.nt ***:We found that roasting tem.erature and hot air velocity had significant effect on colour *** is a correlation between a-and b-value with chlorophylls and xanthophylls concentration,*** roasting tem.erature was found to be the m.in factor affecting colour *** variations in the pigm.nts concentration and colour param.ters of pistachio nuts were adequately sim.lated by quadratic and cubic *** changes in L-,b-values,and xanthophylls degradation were well-fitted to the first-order kinetic m.del while a-value and chlorophylls degradation followed the zero-order *** activation energy was determ.ned at 113.9,116.7,and 117.2 kJ/m.l with R2≥99.9 and 191,195,and 163.2 kJ/m.l with R2≥99.5 and 73.7,71.3,and 81.6 kJ/m.l with R2≥99.9 for L-,b-,and a-value in hot air velocity of 0.6,1.3,and 2 m.s,***:Activation energy of chlorophylls and xanthophylls degradation were in the range of the activation energy for the yellowness(b-value)and redness(a-value)reactions.

关键词： colour kinetics roasting process pistachio nuts im.ging analysis