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Inverting a k-heptadiagonal matrix based on Doolitle LU factorization

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Applied Mathematics(A Journal of Chinese Universities) 2022年第3期37卷 340-349页

作者： maryam Shams Solary Mehran Rasouli Department of mathematics Payamenoor universityTehranIran

The purpose of the present paper is to show a new numeric and symbolic algorithm for inverting a general nonsingular k-heptadiagonal *** work is based on Doolitle LU factorization of the *** obtain a series of recursive relationships then we use them for constructing a novel algorithm for inverting a k-heptadiagonal *** computational cost of the algorithm is *** illustrative examples are given to demonstrate the effectiveness of the proposed method.

关键词： k-Heptadiagonal matrices LU factorization algorithm inverse of a matrix

ELECTROSPINNING OF CYCLODEXTRIN FUNCTIONALIZED CHITOSAN/PVA NANOFIBERS AS A DRUG DELIVERY SYSTEM

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Chinese Journal of Polymer Science 2013年第10期31卷 1343-1351页

作者： maryam Bazhban Mahdi Nouri Javad Mokhtari Department of Textile Engineering Faculty of Engineering University of Guilan

A new type ofnanofibrous structure from chitosan bearing carboxymethyl-β-cyclodextrin （CS-g-β-CD） as a novel drug delivery system was synthesized by grafting carboxymethyl-β-cyclodextrin （CM β-CD） onto chitosan （CS） in the presence of water soluble 1-ethyl-3-（3-dimethylaminopropyl） carbodiimide （EDC） as the condensing agent and N-hydroxysuccinimide （NHS）. Defect free mats containing CS-g-β-CD have been fabricated using electrospirming of an aqueous solution of poly（vinyl alcohol）（PVA）/CS-g-β-CD blends. The morphology and diameter of the electrospun nanofibers were examined by scanning electron microscopy （SEM）. The average fiber diameter was in the range of 130-210 run. SEM images showed that the morphology and diameter of the nanofibers were mainly affected by weight ratio of the blend at constant applied voltage. The results revealed that increasing CS-g-β-CD content in the blends decreases the average fiber diameter. It was observed that the PVA/CS-g-β-CD nanofibrous mat provided a slower release of the entrapped drug in compare to PVA/CS nanofibrous mat.

关键词： Chitosan βcyclodextrin Nanofibers Drug delivery.

Effects of Wind Turbines Equipped with Doubly-fed Induction Generators on Distance Protection

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电力系统自动化 2012年第8期36卷 128-131页

作者： Hossein Kazemi KAREGAR maryam KHODDAM Faculty of Electrical &Computer Engineering Shahid Beheshti University

Nowadays wind energy is the fastest growing renewable energy resource in the *** problems of integrating wind farms are caused by changes of wind speed during a ***,the behaviors of wind turbines equipped with doubly-fed induction generators differ fundamentally from synchronous ***,more considerations are needed to analyze the performances of the distance protection *** protection of a wind farm with distance relay is *** changing the conditions of the wind farm,the characteristics of the distance relay are studied.

关键词：距离保护双馈异步发电机风力发电机组配备可再生能源资源双馈感应发电机距离继电器同步发电机

Improvement in the protective performance and adhesion of polypyrrole coating on AZ31 Mg alloys

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Progress in Natural Science:Materials International 2015年第5期25卷 478-485页

作者： maryam Hatami Mohsen Saremi Reza Naderi School of Metallurgy and Materials Engineering Faculty of Engineering University of Tehran

The electrochemical synthesis of polypyrrole(Ppy) coating on AZ31 magnesium alloy was successfully achieved in a solution containing sodium salicylate and monomer of pyrrole through cyclic voltammetry *** effect of potential range,passivation pretreatment and number of cycles of polymerization on the quality and protective performance of the coatings was evaluated using surface analysis and electrochemical *** taking the advantage of charge transfer resistance,current density,corrosion potential,optical microscopy images and SEM micrographs,the optimum condition of synthesis of a Ppy coating with the best adhesion and corrosion protection was *** optimal PPy coating synthesized over AZ31 increases the polarization resistance and decreases the corrosion current more than one order of magnitude and shift the corrosion potential about 200 mV toward nobler *** SEM studies showed that Ppy coating have cauliflower morphology of Ppy grains with a diameter ranging from 20 nm to 60 nm.

关键词： PolyPyrrole AZ31 Mg Cyclic voltammetry Electropolymerization Corrosion protection

Gradient microstructure and enhanced mechanical performance of magnesium alloy by severe impact loading

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Journal of Materials Science & Technology 2020年第1期36卷 45-49页

作者： maryam Jamalian David P.Field School of Mechanical and Materials Engineering.Washington State University PullmanUSA

Subjecting a workpiece to a surface treatment with severe impact loading is a novel severe plastic deformation procedure to fabricate gradient microstructures through the thickness and longitudinal *** performance is a function of twin density and the newly-formed grain size gradients.{1012}tensile twins created from processing without excessive grain refinement lead to strength enhancement with retained *** of residual strain by a single impact results in a significant reduction in time and cost of the *** paper investigates the effect of applying severe impact loading on mechanical and microstructural properties of magnesium for various impact velocities.

关键词： Surface modification Twinning Magnesium alloys Mechanical properties Severe impact loading(SIL)

The role of geometrical features in the architecturalstructural interaction:Some case studies of the Iranian ancient architecture

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Frontiers of Structural and Civil Engineering 2019年第3期13卷 716-724页

作者： maryam ZANDIYEHVAKILI Isa HOJAT Mehdi MAHMUDI Faculty of Architecture and Urban Development Art University of IsfahanIsfahanIran Faculty of Architecture College of Fine ArtsUniversity of TehranTehranIran

This research aims to enhance the interaction between a structure and its architectural *** a qualitative approach,the present work discovers some successfully used geometrical features of the Iranian ancient architecture in terms of the architectural-structural *** define four qualitative criteria for this assessment,i.e.,construction-ability,cost effectiveness,participation of the structure in fulfillment of the visual,and functional-semantic needs of the architectural *** this purpose,two case studies including the Jame Mosque of Isfahan and the Soltaniyeh building are *** outcomes of this research help designers to not only design efficient structures by adapting non-load bearing elements with the general form of the structure,but also meet concepts such as the unity or perfectionism in the structure.

关键词： architectural-structural interaction geometrical features structure architectural form Iranian ancient architecture

The Release Behavior,Biocompatibility and Physical Properties of Aid-loaded Strontium Doped Calcium Phosphate Cement

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Journal of Bionic Engineering 2020年第6期17卷 1209-1223页

作者： maryam Mohammadi Sayed Mahmood Rabiee Saeed Hesaraki Department of Materials Engineering Babol Noshirvani University of TechmologyBabol 71167-47148Iran Nanotechnologv and Advanced Materials Materials and Energy Research CenterKaraj ***AlborzIran

The effect of concurrent attendance of two inhibitors of bone degradation,namely Alendronate(Aid)sodium trihydrate and Strontium(Sr),on Calcium Phosphate Cement(CPC)characteristics was *** this aim,5 wt%Strontium and 21 mM Alendronate sodium trihydrate were used in calcium phosphate cement and setting time,ion and drug release were ***264.7 and G cell were cultured on cement samples and Tartrate-Resistant Acid Phosphatase(TRAP),Alkaline phosphatase(ALP)activity and MTT assay were *** results of structural analysis indicated that 21 mM Aid did not let the cement ***,colloidal silica was added to the cement formula and successfully decreased the setting *** vitro tests showed Sr-loaded sample had a greater inhibitory effect on biocompatibility of G cells than Aid-loaded and Sr-Ald-loaded *** addition,the findings about osteoblast MTT and ALP activity indicated that Sr was more effective in osteogenic activity of G *** simultaneous presence of Aid and Sr in Calcium Phosphate Cement(CPC)was not as effective in its biocompatibility as the presence of Sr alone.

关键词： calcium phosphate cements drug release alendronate sodium trihydrate strontium RAW264.7 cell G cell

Numerical investigation of flow pattern and components of three-dimensional velocity around a submerged T-shaped spur dike in a 90° bend

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Journal of Central South University 2016年第11期23卷 2984-2998页

作者： Mohammad Vaghefi Yaser Safarpoor maryam Akbari Department of Civil Engineering Persian Gulf University

Spur dike is one of the river training structures. This work presented a numerical simulation of flow field and three-dimensional velocity around a T-shaped spur dike located in bend using SSIIM model. The main objective of this work is to investigate the three-dimensional velocities and streamlines at transverse and longitudinal sections and plan views around the T-shaped spur dike in different submergence ratios(0, 5%, 15%, 25% and 50%). It is concluded that by increasing the submergence ratio from 5% to 50%, the maximum of scour is reduced; the maximum of longitudinal velocity increases by 7.7% and occurs at the water surface in spur dike axis. Near the bed, the maximum of vertical velocity occurs at the end of spur wing. By analyzing the streamlines at transverse sections, the followings were deduced for different submergence ratios: different dimensions and different positions of vortices around the spur dike.

关键词： T-shaped spur dike flow pattern submergence ratio SSIIM model

Advanced development in upstream of petroleum industry using nanotechnology

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Chinese Journal of Chemical Engineering 2020年第6期28卷 1483-1491页

作者： Sedigheh Sadegh Hassani maryam Daraee Zahra Sobat Catalysis research Division Research Institute of Petroleum Industry(RIPI)West Entrance Blvd.Olympic VillageP.O.Box 14857-33111TehranIran Nanotechnology Research Center Research Institute of Petroleum Industry(RIPI)West Entrance Blvd.Olympic VillageP.O.Box 14857-33111TehranIran

Nowadays,energy supply is one of the most important issues due to limitation of oil,gas and coal *** of rapid population,civilization and energy consumption growth,the improved technologies to make optimal use of the sources,solving related problems and finding new energy sources are *** than 10 years ago,nanotechnology as one of the most important technologies has also been applied to progress in the oil and gas industry(upstream,midstream and downstream).The experience of these years has shown that application of nanotechnology in the oil industry improves the exploration of crude oil and natural gas(underground or deep water),drilling and bringing the crude oil or raw natural gas to the surface,as well as transportation,storage,processing and purifying *** with high specific surface area,pore volume and small size show unique physical and chemical properties,which could be applied in several *** this regard,many researchers have been focused on various nanoparticles for upstream industries and studied their potential in oil exploration,drilling,production and enhanced oil recovery(EOR).Also,in downstream and midstream which involve refining of crude oil,processing and purifying of raw natural gas,transportation and storage of crude or refined petroleum products,the nanomaterials have been used to improve the quality of oil and make it appropriate for the *** sulfur gasoline,enhancing the octane number and coating the transportation system are among the goals that have been achieved successfully using *** this work,various types of nanoparticles such as metallic,metal oxide,hybrid nanoparticles,carbon nanomaterials,nano-composites and their applications in oil upstream industry are ***,their usage in different types of oil upstream processes is discussed.

关键词： Nanotechnology Oil exploration Oil drilling Nanoparticles Enhanced oil recovery