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Effects of Yttrium Addition on Microstructure, Hardness and Resistance to Wear and Corrosive Wear of TiNi Alloy

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Journal of Materials Science & Technology 2011年第9期27卷 851-855页

作者： Hojat Ahmadi meisam nouri Faculty of Biosystems Engineering University of Tehran Department of Materials Engineering Tarbiat Modares University

TiNi alloy has a high resistance to wear and could be an excellent candidate for various tribological applications. In this paper, it was demonstrated that by addition of yttrium, hardness properties and resistance to wear and corrosive wear of TiNi alloy were improved. New yttrium rich regions were formed in microstructure of TiNi alloy. The improved properties of this alloy by the yttrium addition could be attributed to the formation of these regions. The results showed that there was an optimum content for addition of yttrium between 2% and 5% （in wt%）, and above this content the improvement in properties of TiNi became minor.

关键词： Yttrium TiNi Mechanical behaviour Wear Corrosive wear Microstructure

Antibacterial activity of bioceramic coatings on Mg and its alloys created by plasma electrolytic oxidation(PEO): A review

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Journal of Magnesium and Alloys 2022年第1期10卷 88-106页

作者： Arash Fattah-alhosseini Maryam Molaei meisam nouri Kazem Babaei Department of Materials Engineering Bu-Ali Sina UniversityHamedan 65178-38695Iran

Mg and its alloys are suitable choices for implant materials due to their biodegradability and biocompatibility features. However, the high electrochemical activity of this family of biomaterials results in their fast degradation and severe corrosion in the physiological environment,producing hydrogen(H;) gas, and therefore increasing the p H of the environment. To meet the clinical requirements, the degradation rate of Mg biomaterials needs to be reduced. Nevertheless, higher corrosion resistance of Mg results in a low alkaline p H, weakening the antibacterial activity. Therefore, while the rapid degradation problem of Mg-based biomaterials needs to be addressed, good antibacterial properties are also necessary. By using the plasma electrolytic oxidation(PEO) surface modification technique, the antibacterial activity of Mg and its alloys can be enhanced while maintaining their corrosion protection properties at a high level. Throughout the PEO process, introducing antibacterial agents into solutions results in a major increase in antibacterial activity of the coatings. Moreover, post-or pre-processing on PEO coatings can provide better protection against bacteria. In this review, the antibacterial activity of PEO coatings applied on Mg and also its alloys will be discussed in more detail.

关键词： Antibacterial activity Magnesium Plasma electrolytic oxidation(PEO) Gram-positive bacteria Gram-negative bacteria

Effects of Yttria Addition on Microstructure,Mechanical Properties,Wear Resistance and Corrosive Wear Resistance of TiNi Alloy

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Journal of Materials Science & Technology 2009年第5期25卷 645-648页

作者： Hojat Ahmadi D.Y.Li meisam nouri Faculty of Biosystems Engineering University of TehranIran Department of Chemical and Materials Engineering University of AlbertaEdmontonCanada Department of Materials Engineering Tarbiat Modares UniversityTehranIran

TiNi alloy has a high resistance to wear and could be an excellent candidate for various tribological applications. But studies show that oxygen active elements can improve properties of some alloys, markedly. Yttrium is one of the oxygen active elements. In this paper, the effects of yttria addition on properties of TiNi have been studied via micro-indentation, hardness, wear and corrosive wear tests. It is demonstrated that by addition of yttria to 5%, TiNi alloy can own improved mechanical properties and resistance to wear and corrosive wear.

关键词： Yttria TiNi Mechanical behavior Wear corrosive Wear

A review of effective strides in amelioration of the biocompatibility of PEO coatings on Mg alloys

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Journal of Magnesium and Alloys 2022年第9期10卷 2354-2383页

作者： Arash Fattah-alhosseini Razieh Chaharmahali Kazem Babaei meisam nouri Mohsen K.Keshavarz Mosab Kaseem Department of Materials Engineering Bu-Ali Sina UniversityHamedan 65178-38695Iran Department of Mechanical and Mechatronics Engineering University of WaterlooWaterlooON N2L 3G1Canada Department of Nanotechnology and Advanced Materials Engineering Sejong UniversitySeoul 05006Republic of Korea

Recently,developing bioactive and biocompatible materials based on Mg and Mg-alloys for implant applications has drawn attention among researchers owing to their suitable body *** Mg and its alloys reduces the risk of long-term incompatibility with tissues because of their close mechanical properties and no need for re-operation to remove the ***,the degradation rate of the implant needs to be controlled because production of hydrogen gas and accumulation of its bubbles increases local pH around the *** confine the integrity of implants and the body,the corrosion concern in the body fluid requires to be *** modification as one of the effective strategies can improve corrosion ***,it creates a suitable surface for bone grafting and cell *** development of proper surface-coated implants needs appropriate techniques and *** electrolytic oxidation(PEO)coating can provide long-term protection by providing a ceramic layer and improving the implant’s ***,a general review of in-vivo and in-vitro evaluation of PEO coatings on Mg and Mg-alloys has been carried *** advances in surface modification on Mg and Mg-alloys have been discussed,however,the need for reliable laboratory models to predict in-vivo degradation is still valid.

关键词： Mg alloys Biodegradation Surface modification In-vivo In-vitro PEO coatings

The Combination Effect of Daphne Extract and Imatinib on the Antiproliferative Activity of the K562 Cell Line

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Journal of Biosciences and Medicines 2024年第8期12卷 141-153页

作者： Alireza Khorshid Jafar nouri Nojadeh Javid Sabour Takanlu Alireza Tavasoli Department of Clinical Laboratory Sciences University of Texas Medical Branch at Galveston Galveston TX USA Department of Medical Genetics Faculty of Medicine Tabriz University of Medical Sciences Tabriz Iran Apoptosis Research Centre Department of Biochemistry School of Natural Sciences National University of Ireland Galway Galway Ireland Department of Pathology School of Medicine Fasa University of Medical Science Fasa Iran

Background: Herbal medicine is well-known among the ancient medical sciences. Healing properties have been observed in some species of Daphne plant. The effect of Daphne plant extract on the K562 cell line has been previously studied, and Gleevec is a well-known and effective medicine for the treatment of chronic myelogenous leukemia. Material and Methods: In this study, the simultaneous effects of using herbal medicine and a target therapy medicine on the K562 cell line were investigated. The presence of some species of Daphne in Iran motivated us to evaluate the cytotoxic effect of Daphne mucronata on human leukemia cancer cells. The antiproliferative activity of the dichloromethane extract of Daphne mucronate (Thymelaeaceae), a new anticancer medicinal plant, was evaluated. Cell viability was quantitated by MTT assay. Apoptotic and necrotic changes in the cell membrane were examined using flow cytometry. Changes in Bax and Bcl2 gene expression were investigated using real-time PCR. The MIC and the IC50 of the crude extract were calculated, and the MIC and IC50 of the Daphne extract in combination of imatinib were tested in the K-562 cell line. Results: K-562 cells responded to the extract treatments in a dose-dependent manner, and the increase in the expression of Bcl2 and decrease in the expression of the Bax gene intensified with increasing extract concentration. Flow cytometry revealed that most of the cells underwent necrosis. Conclusion: Daphne extract effectively decreased the viability of the K562 cell line. The necrotic effect of the Daphne extract was evaluated, and an increase in the gene expression of Bcl2 was observed in cells exposed to the Daphne extract. The combination of Daphne extracts with imatinib enhances the cytotoxic effect of imatinib.

关键词： Daphne Imatinib Apoptosis Herbal Medicine Bax Bcl-2 CML

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.

NAPHTHALIMIDE BASED DISPERSE DYES FOR NYLON 6 AND POLYESTER(PET) FIBERS:SYNTHESIS AND EVALUATION OF TECHNICAL PROPERTIES IN THE PRESENCE OF UREA

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Chinese Journal of Polymer Science 2011年第6期29卷 712-718页

作者： Javad Mokhtari Mahdi nouri Uranus Goudarzi Department of Textile Engineering Faculty of EngineeringUniversity of GuilanRashtIran

Technical properties of two naphthalimide based disperse dyes on nylon 6 and polyester fibers were investigated in the presence of urea. The two naphthalimide based disperse dyes were synthesized. The dyes were purified and then fully characterized using 1H-NMR, FTIR and melting point analysis. Dispersion of the dyes was prepared in water and applied on nylon 6 and PET fibers. The dyes offered good build-up properties on the substrates. In order to increase dye adsorption of the substrates, urea was added into the dyebath. By adding urea, the dye adsorption of polyester was increased significantly, while the increase of that of nylon 6 was not marked. The dyes showed good fastness properties on the substrates.

关键词： Naphthalimide Nylon 6 Polyester Urea Disperse dye

Applying Sliding Mode Control to Suppress Double Frequency Voltage Ripples in Single-phase Quasi-Z-source Inverters

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CSEE Journal of Power and Energy Systems 2023年第2期9卷 671-681页

作者： Jaber Merrikhi Ahangarkolaei Mahdi Izadi Tohid nouri Department of Electrical Engineering Sari BranchIslamic Azad UniversitySariIran Department of Electrical Engineering Shahriar BranchIslamic Azad UniversityShahriarIran

The inherent double-line frequency ripple(DFR)of the single-phase quasi-Z-Source inverter(qZSI)strongly affects performance and design of the whole system,which requires hardware improvement methods such as additional semiconductor components or increasing the volume of capacitors and *** a result,hardware solutions increase the price,and the volume and also reduces reliability of the *** this paper,as a non-hardware solution,a sliding mode control(SMC)method is presented to control the voltage of the qZSI *** suppress the DFR,a second-order harmonic is injected into the capacitor reference *** and experimental results show that the introduced controller will have satisfactory results in reducing the DFR without any hardware changes in the qZSI,such as increasing the volume of the capacitor and inductor,adding a semiconductor,or increasing the frequency.A simulation model and experimental prototype are provided to demonstrate the validation of the effectiveness of the proposed controller.

关键词： Double-frequency ripple quasi-Z-source inverter sliding mode control

DRAG REDUCTION IN A TURBULENT CHANNEL FLOW WITH HYDROPHOBIC WALL

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Journal of Hydrodynamics 2012年第3期24卷 458-466页

作者： nouri Nowrouz Mohammad SEKHAVAT Setareh MOFIDI Alireza Department of Mechanical Engineering Iran University of Science and TechnologyTehran Iran

This paper investigates a theoretical prediction of friction drag reduction in turbulent channel flow which is achieved by using superhydrophobic surfaces. The effect of the hydrophobic surface is considered to be a slip boundary condition on the wall, and this new boundary condition is added to Large Eddy Simulation （LES） equations. The predicted drag reduction at Rer= 180 is approximately 30%, which concurs with results obtained from Direct Numerical Simulation （DNS）. An important implication of the present finding is that the near-wall turbulence structures are modified with streamwise slip velocity. In addition, a noticeable effect on the turbulence structure occurs when the slin lenmh is ereater than a certain vahle

关键词： superhydrophobic surface Large Eddy Simulation (LES) drag reduction slip length turbulence structures