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Combinatorial Algorithms for Reverse Selective Undesirable Center Location Problems on Cycle Graphs

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Journal of the Operations Research Society of China 2017年第3期5卷 347-361页

作者： Roghayeh Etemad Behrooz alizadeh Department of Applied Mathematics Faculty of Basic SciencesSahand University of TechnologyTabrizIran

This paper deals with a general variant of the reverse undesirable(obnoxious)center location problem on cycle *** a‘selective’subset of the vertices of the underlying cycle graph as location of the existing customers,the task is to modify the edge lengths within a given budget such that the minimum of distances between a predetermined undesirable facility location and the customer points is maximized under the perturbed edge *** develop a combinatorial O(n log n)algorithm for the problem with continuous *** the uniform-cost model,we solve this problem in linear time by an improved ***,exact solution methods are proposed for the problem with integer modifications.

关键词： Undesirable center location Reverse optimization Combinatorial optimization Time complexity

Environmentally Benign Oxidation of Some Organic Sulfides with 34% Hydrogen Peroxide Catalyzed by Simple Heteropolyoxometalates

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Chinese Journal of Chemistry 2007年第9期25卷 1340-1343页

作者： TAYEBEE, Reza alizadeh, Mohammad Hassan Department of Chemistry Sabzevar University Sabzevar 397 lran Department of Chemistry Ferdowsi University Mashhad 91779 lran

An environmentally benign oxygenation protocol was developed for selective oxidation of some types of aromatic and aliphatic sulfides in good to excellent yields utilizing 34% hydrogen peroxide catalyzed by simple heteropolyoxometalates in normal drinking water at room temperature. The catalysts could be recovered and reused for at least seven reaction cycles under the described reaction conditions without considerable loss of reactivity. This procedure introduced a new insight into the use of simple heteropolyanions as recoverable catalysts for the oxidation of organic sulfides by an environmentally acceptable protocol. Keywords

关键词： oxidation heteropolyacid catalysis hydrogen peroxide organic sulfide

Optimal Algorithms for Integer Inverse Undesirable p-Median Location Problems on Weighted Extended Star Networks

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Journal of the Operations Research Society of China 2021年第1期9卷 99-117页

作者： Esmaeil Afrashteh Behrooz alizadeh Fahimeh Baroughi Department of Applied Mathematics Faculty of Basic SciencesSahand University of TechnologyTabrizIran

This paper is concerned with the problem of modifying the edge lengths of a weighted extended star network with n vertices by integer amounts at the minimum total cost subject to be given modification bounds so that a set of p prespecified vertices becomes an undesirable p-median location on the perturbed *** call this problem as the integer inverse undesirable p-median location *** combinatorial algorithms with O(p2n logn)and O(p2(n logn+n log nmax))running times are proposed for solving the problem under the weighted rectilinear and weighted Chebyshev norms,***,it is shown that the problem under the weighted sum-type Hamming distance with uniform modification bounds can be solved in O(p-n log n)time.

关键词： Undesirable p-median location Combinatorial optimization Inverse optimization Time complexity

Effect of crystallographic texture and twinning on the corrosion behavior of Mg alloys:A review

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Journal of Magnesium and Alloys 2022年第2期10卷 332-345页

作者： Ehsan Gerashi Reza alizadeh Terence G.Langdon Department of Materials Science and Engineering Sharif University of TechnologyTehranIran Materials Research Group Department of Mechanical EngineeringUniversity of SouthamptonSouthampton SO171BJUnited Kingdom

Magnesium and its alloys have gained significant popularity due to their light weight and their potential for use as bioresorbable ***,their application is limited in practice due to their relatively poor corrosion *** methods are available for improving the corrosion resistance of Mg alloys for bio-applications such as using different coatings,alloying,and modifying the microstructural parameters such as the grain size and the crystallographic *** review provides a comprehensive summary of the effects of crystallographic texture and twinning,as one of the most important deformation mechanisms of Mg and Mg alloys,on the corrosion *** the crystallographic texture,it is shown that theoretically the basal planes should exhibit a lower corrosion rate but in some cases,such as when there is a galvanic effect or when corrosion films control the overall corrosion behavior,different results may take ***,there are contradictory results concerning the effect of twinning on the corrosion ***,in some cases twinning may provide preferential sites for corrosion due to the higher energies of atoms located in the twin region by comparison with normal atomic positions in the crystalline lattice whereas there are also other examples where experiments show that twins produce more protective films than in the surrounding matrix.

关键词： Bio-materials Corrosion Magnesium Texture Twinning

Simultaneous colorimetric determination of morphine and ibuprofen based on the aggregation of gold nanoparticles using partial least square

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Journal of Pharmaceutical Analysis 2017年第6期7卷 411-416页

作者： Morteza Bahram Tayyebeh Madrakian Sakineh alizadeh Department of Chemistry Faculty of Science Urmia University Department of Analytical Chemistry Faculty of Chemistry Bu-Ali Sina University

In this work a new method is presented for simultaneous colorimetric determination of morphine （MOR） and ibuprofen （IBU） based on the aggregation of citrate-capped gold nanoparticles （AuNPs）. Citrate-capped AuNPs were aggregated in the presence of MOR and IBU. The difference in kinetics of AuNPs aggregation in the presence of MOR/IBU was used for simultaneous analysis of MOR and IBU. The formation and size of synthesized AuNPs and the aggregated forms were monitored by infra-red （IR） spectroscopy and transmission electron microscopy （TEM）, respectively. By adding MOR or IBU the absorbance was decreased at 520 nm and increased at 620 nm. The difference in kinetic profiles of aggregation was applied for simultaneous analysis of MOR and IBU using partial least square （PLS） regression as an efficient multivariate calibration method. The number of PLS latent variables was optimized by leave-one-out cross-validation method using predicted residual error sum of square. The proposed model exhibited a high capability in simultaneous prediction of MOR and IBU concentrations in real samples. The results showed linear ranges of 1.33-33.29 μg/mL （R2=0.9904） and 0.28-6.9 μg/mL （R2=0.9902） for MOR and IBU respectively with low detection limits of 0.15 and 0.03 μg/mL（S/N=5）.

关键词： Morphine Ibuprofen Simultaneous determination AuNPs Partial least squares

The Role of Local Communities： A Modification for the Knowledge- Based Regional Development Theory

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学术界 2010年第1期 249-257页

作者： Tooran alizadeh University of Sydney Australia

By the turn of the 21 st century,the significance of knowledge to be the key factor in urban and regional development is well established. However,it has been recently and in only a few studies that attempts have been made to identify the specific mechanism and institutional relationships,through which knowledge-based development actually takes *** paper builds upon the "Triple Helix Model" (Etzkowitz & Klofsten,2005) where university,business and government have been introduced as the key factors behind any knowledge-based *** refers to a case study of knowledge-based community development in Australia's Smart State Queensland-and examines the role of the "Triple Helix" in the interaction between local and regional *** shows the central role of the community as an innovation base for the interaction among the key factors and suggests a promotion for a Quadruple Helix Model where community is as important as business,university and government in the new *** paper concludes that knowledge-based development will not promote unless all four factors-community,business,university,government-work together.

关键词：地方经济发展理论 21世纪

Fluid Flow and Mixing in Non-Isothermal Water Model of Continuous Casting Tundish

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Journal of Iron and Steel Research International 2008年第2期15卷 7-13,22页

作者： Mehdi alizadeh Hossein EDRIS Ali SHAFYEI Department of Materials Engineering Isfahan University of Technology

Fluid flow and mixing of molten steel in a twin-slab-strand continuous casting tundish were investigated using a mixing model under non-isothermal *** model led to a set of ordinary differential equations that were solved with a Runge-Kutta *** state water modeling was carried out under non-isothermal *** data obtained from the water model were used to calibrate the mixing *** to the presence of a mixed convection in the non-isothermal conditions,a channelizing flow would be created in the fluid inside the tundish.A mixing model was designed that was capable of predicting RTD（residence time distribution）curves for different cases in non-isothermal *** relationship between RTD parameters and the Tu（tundish Richardson number）was obtained for various cases under non-isothermal *** results show that the RTD parameters were completely different under isothermal and non-isothermal *** comparison of the RTD curves between the isothermal and non-isothermal conditions presents that the extent of mixing in the tundish in non-isothermal conditions is lower than the mixing extent in isothermal conditions.

关键词： tundish non-isothermal condition mixing model water modeling

Recent advances using equal-channel angular pressing to improve the properties of biodegradable Mg-Zn alloys

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Journal of Magnesium and Alloys 2023年第7期11卷 2260-2284页

作者： Mohammad Hashemi Reza alizadeh Terence G.Langdon Department of Materials Science and Engineering Sharif University of TechnologyTehranIran Materials Research Group Department of Mechanical EngineeringUniversity of SouthamptonSouthampton SO171BJUnited Kingdom

Magnesium alloys are of considerable current interest for use as degradable implants due to their unique properties including biodegrad-ability,biocompatibility,low density and adequate mechanical ***,there is a need to further improve these properties either by alloying or through the use of appropriate *** the different biodegradable Mg alloys now in use,the Mg-Zn series are of special interest and have been the subject of many research *** is primarily because Zn is an essential element for the human body in addition to its positive effects in improving the mechanical strength and lowering the degradation rate of the *** properties of Mg-Zn alloys may be further improved both through the addition of third and fourth alloying elements such as Ca,Ag,Sn or Sr and/or by thermo-mechanical processing where the latter is more environmentally and economically *** practice,procedures based on the application of severe plastic deformation(SPD)are especially suited to produce fine-grained microstructures with improved mechanical,degradation and cell ***-channel angular pressing(ECAP)is a popular SPD technique that has the capability of pro-ducing bulk materials that are sufficiently large for use as typical ***,this review is designed to provide a comprehensive summary of the research that has been undertaken on ECAP-processed biodegradable Mg-Zn alloys.

关键词： Bio-degradation ECAP Fine-grained microstructure Mg–Zn alloys Severe plastic deformation

Effect of Oxidizing Atmosphere on the Surface of Titanium Dental Implant Material

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Journal of Bionic Engineering 2019年第6期16卷 1052-1060页

作者： Mohammad Khodaei Akram alizadeh Hamid Reza Madaah Hosseini Department of Materials Science and Engineering Golpayegan University of TechnologyGolpayegan 87717-65651Iran Department of Tissue Engineering School of Advanced TechnologiesShahrekord University of Medical SciencesShahrekord 88157-13471Iran Department of Materials Science and Engineering Sharif University of TechnologyTehran 14588-89694Iran

Direct oxidation is a simple and effective method for titanium surface *** this research,a titanium sample was directly oxidized at the high temperature in two different atmospheres,air and pure oxygen,to obtain better atmosphere for titanium surface *** results of the Raman spectroscopy indicated that in both atmospheres,the rutile bioactive phase(TiO2)has been formed on the titanium *** results of X-ray diffraction(XRD)also revealed that the surface of oxygen-treated sample was composed of the rutile phase and titanium monoxide(TiO),while at the surface of the air-treated sample,the rutile phase and titanium dioxide had been ***,the results of Field Emission Scanning Electron Microscopy(FE-SEM)showed that by the surface treatment of titanium in both atmospheres,some micro-features including cracks thinner than 30 nm were formed on the *** of more apatite forming ability and fewer water contact angle and more L-929 cell attachment of the air-treated titanium,it seemed that air,in comparison to the pure oxygen,is more promising atmosphere for the direct oxidation of titanium and improving its biofunctionalization.

关键词： titanium implant surface treatment direct oxidation anatase rutile biomedical-materials