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Optoelectronics Letters 2024年第3期20卷 163-170页

作者： mohammad reza alizadeh Mahmood Seifouri Saeed Olyaee Faculty of Electrical Engineering Shahid Rajaee Teacher Training UniversityTehranIran Nano-photonics and Optoelectronics Research Laboratory(NORLab) Shahid Rajaee Teacher Training UniversityTehranIran

In this paper, a photonic crystal fiber(PCF) with a dispersion-engineered and high nonlinear coefficient has been designed for supercontinuum generation(SCG) and frequency comb generation(FCG). The proposed PCF has a Si_(3)N_(4) rod in the core. This rod provides more optical confinement in the core by increasing the refractive index of the core. This high confinement reduces the effective mode area of PCF and thus increases the nonlinear coefficient.

关键词： optical fiber nonlinear

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

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

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

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镁合金学报(英文) 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

Voltammetric determination of venlafaxine as an antidepressant drug employing Gd_2O_3 nanoparticles graphite screen printed electrode

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Journal of Rare Earths 2019年第3期37卷 322-328页

作者： Hadi Beitollahi Shohreh Jahani Somayeh Tajik mohammad reza Ganjali Farnoush Faridbod Taher alizadeh Environment Department Institute of Science and High Technology and Environmental Sciences Graduate University of Advanced Technology NanoBioElectrochemistry Research Center Bam University of Medical Sciences Center of Excellence in Electrochemistry School of Chemistry College of Science University of Tehran Biosensor Research Center Endocrinology & Metabolism Molecular-Cellular Sciences Institute Tehran University of Medical Sciences Department of Analytical Chemistry Faculty of Chemistry College of Science University of Tehran

Graphite screen printed electrode modified with Gd_2 O_3 nanoparticles(Gd_2 O_3/SPE) was developed for the determination of venlafaxine(VF). The Gd_2 O_3 nanoparticles were thoroughly characterized by scanning electron microscopy(SEM), transmission electron microscopy(TEM) and X-ray diffraction(XRD) analyses. To study the electrochemical behaviour of venlafaxine cyclic voltammetry(CV), chronoamperometry(CHA)and differential pulse voltammetry(DPV) were employed. These studies reveal that the oxidation of venlafaxine is facilitated at Gd_2 O_3/SPE. After optimization of analytical conditions, analysis of venlafaxine using the modified electrode in 0.1 mol/L PBS(pH 7.0) demonstrates that the peak currents corresponding to venlafaxine vary linearly with its concentration in the range of 5.0 ×10^(-6)-9.0 × 10^(-4) mol/L. The detection limit(S/N = 3) of 2.1 × 10^(-7) mol/L is obtained for venlafaxine using DPV. The prepared modified electrode benefits from advantages such as simple preparation method, high sensitivity and low detection ***, the evaluation of practical applicability of this proposed method is successful in the identification of venlafaxine in pharmaceutical formulations, urine and water samples.

关键词： Venlafaxine Gd2O3 nanoparticles Electrochemical techniques Screen printed electrode Rare earths

Effects of heat treatment on the corrosion behavior and mechanical properties of biodegradable Mg alloys

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Journal of Magnesium and Alloys 2022年第7期10卷 1737-1785页

作者： Meysam mohammadi Zerankeshi reza alizadeh Ehsan Gerashi mohammad Asadollahi Terence G.Langdon Department of Materials Science and Engineering Sharif University of TechnologyTehranIran Materials Research Group Department of Mechanical EngineeringUniversity of SouthamptonSouthampton SO171BJUnited Kingdom

Biodegradable magnesium(Mg)alloys exhibit great potential for use as temporary structures in tissue engineering *** degradable implants require no secondary surgery for their *** addition,their comparable mechanical properties with the human bone,together with excellent biocompatibility,make them a suitable candidate for fracture ***,some challenges *** degradation of the Mg-based alloys in physiological environments leads to a loss of the mechanical support that is needed for complete tissue healing and also to the accumulation of hydrogen gas bubbles at the interface of the implant and *** different methods used to improve the performance of the biodegradable Mg alloys to address these challenges,it appears that heat treatment is the most effective way to modify the microstructure and thus the corrosion behavior and mechanical properties without changing the composition or shape of the alloys.A desirable combination of corrosion and mechanical properties can be obtained through a precise control of the heat treatment *** this report,the effects of different heat treatments(T4 and T6)on the microstructure,corrosion behavior,and mechanical properties of some of the most important heat-treatable biodegradable Mg alloys(Mg-Zn,Mg-Gd,Mg-Y,Mg-Nd,Mg-Al and Mg-Ag)are examined as well as new perspectives to enhance their clinical implementation.

关键词： Biodegradable implants Corrosion rate Heat treatment Mechanical properties Mg alloys

Secure ticket-based authentication method for IoT applications

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Digital Communications and Networks 2023年第3期9卷 710-716页

作者： Mojtaba alizadeh mohammad Hesam Tadayon Alireza Jolfaei Computer Engineering Department Lorestan UniversityKhorramabadIran Iran Telecommunication Research Center(ITRC) TehranIran Department of Computing Macquarie UniversitySydneyAustralia

The recent surge in the number of machines,appliances,and services connected to the Internet demands secure processing and transmission of sensory *** plays a crucial role in a typical security model used in the Internet of Things(IoT),and it protects data communications from various attacks,such as impersonation and denial of service,by verifying and allowing legitimate users to access the IoT ***,recent authentication literature has not addressed the need for developing a scalable and efficient authentication method in this *** paper proposes a secure and anonymous ticket-based authentication method for the *** proposed method protects the network from various security and privacy threats such as data alternation and denial of service while also offering mutual authentication and sensor *** security and performance evaluations confirm the improvement.

关键词： IoT Internet of things Authentication Privacy Security

Modulation of the gut microbiota represents a new management for non-alcoholic fatty Iiver disease

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Hepatobiliary Surgery and Nutrition 2020年第2期9卷 223-226页

作者： Farnush Bakhshimoghaddam mohammad alizadeh Student Research Committee Department of Nutrition Department of Nutrition Food and Beverages Safety Research CenterFaculty of MedicineUrmia University of Medical SciencesUrmiaIran

With the worldwide spread of diet westernization,sedentary lifestyle,and obesity,non-alcoholic fatty liver disease(NAFLD)has becoming frequent *** is the presence of hepatic fat infiltration more than 5%of liver cells,in lack of alcohol abuse or steatogenic *** includes a spectrum of liver disorder,ranging from steatosis and non-alcoholic steatohepatitis(NASH)to fibrosis,cirrhosis and hepatocellular carcinoma(1).Metabolic syndrome and systemic micro-inflammation are the most relevant metabolic disorders related to this spectrum of diseases(2).There is currently no approved pharmacological treatment for *** management strategy of NAFLD involves lifestyle interventions,including diet,exercise,and behavior modification(1).

关键词： drugs inflammation becoming

Effects of sodium nitroprusside on callus browning of Ficus religiosa: an important medicinal plant

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Journal of Forestry Research 2020年第3期31卷 789-796页

作者： Mohsen Hesami Masoud Tohidfar Milad alizadeh mohammad Hosein Daneshvar Department of Horticultural Science Faculty of AgricultureUniversity of TehranKarajIran Department of Plant Biotechnology Faculty of Life Science and BiotechnologyShahid Beheshti UniversityTehranIran Department of Horticultural Science Faculty of AgricultureKhuzestan Agricultural Sciences and Natural Resources UniversityMollasaniIran

Tissue browning is a major problem in tissue culturing of woody plants, especially for Ficus religiosa which occurs by the accumulation and oxidation of phenolic compounds. This study aimed to determine the effect of different concentrations of sodium nitroprusside on the appearance of callus browning from leaf explants. The results indicate that callus browning was significantly reduced by supplementation of sodium nitroprusside to the MS medium and supplemented with 2.26μM of 2,4-dichlorophenoxyacetic acid and 0.22μM of 6-benzyl amino purine. The accumulation of hydrogen peroxide and phenolic compounds in the callus tissues decreased at the 50 μM concentration of sodium nitroprusside. Although catalase and peroxidase activities decreased at the 50μM concentration, the activity of superoxide dismutase and polyphenol oxidases, as well as proline content, increased exponentially. Sodium nitroprusside could be useful for the formation of non-embryogenic callus with high levels of metabolic activity for the production and isolation of secondary metabolites.

关键词： Nitric oxide Oxidative enzymes Proline Reactive oxygen species

Predictive value and main determinants of abnormal features of intraoperative cholangiography during cholecystectomy

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Hepatobiliary & Pancreatic Diseases International 2011年第3期10卷 308-312页

作者： Shahram Yousefpour Azary Heshmat Kalbasi Ali Setayesh Mirhadi Mousavi Asad Hashemi Mahsa Khodadoostan mohammad reza Zali Amir Houshang mohammad alizadeh Research Center for Gastroenterology and Liver Diseases Shahid Beheshti University of Medical SciencesTaleghani Hospital Arad General Hospital

BACKGROUND:The major issue with intraoperative cholangiography (IOC) is whether its diagnostic accuracy for common bile duct (CBD) stones matches that of other diagnostic procedures,and thus,whether it will become a routine diagnostic *** current study aimed to address the main determinants of CBD stone diagnosis in IOC among an Iranian ***:In a retrospective review database-based study conducted in Taleghani Hospital in Tehran between 2006 and 2008,baseline data and perioperative information of 2060 patients (male to female ratio 542:1518,mean age 53.7 years) who were candidates for cholecystectomy and underwent concomitant IOC for confirming CBD stones were *** predictive power of this procedure for diagnosis of abnormal biliary ducts with the focus on biliary stones was ***:Overall mortality and morbidity following cholecystectomy in the study population were 0.6% and 2.6%,*** early mortality and morbidity due to cholecystectomy were higher in male than *** prevalence of CBD stones in IOC was 3.4% (5.2% in male and 2.8% in female,P=0.008).Among those without gallstones,8.7% had CBD stones and only 3.1% had concomitant gallstones and CBD *** main predictors of stone appearance as an abnormal feature of IOC during cholecystectomy were:advanced age (OR=1.022,P=0.001),male gender (OR=1.498,P=0.050),history of abdominal surgery (OR=1.543,P=0.040) and preoperative endoscopic retrograde cholangiopancreatography (OR=5.400,P<0.001).CONCLUSIONS:IOC is a safe and accurate method for the assessment of bile duct anatomy and ***,the routine use of IOC within cholecystectomy seems reasonable and is recommended.

关键词： intraoperative cholangiography common bile duct stone cholecystectomy predictive value diagnostic accuracy