检索结果-南通市图书馆

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

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

在线全文

学校读者我要写书评

暂无评论

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

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

在线全文

学校读者我要写书评

暂无评论

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

在线全文

学校读者我要写书评

暂无评论

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

Numerical simulation of fatigue crack propagation in heterogeneous geomaterials under varied loads using displacement discontinuity method

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Rock Mechanics and Geotechnical Engineering 2023年第3期15卷 702-716页

作者： Rezvan alizadeh mohammad Fatehi Marji Abolfazl Abdollahipour Mehdi Pourghasemi Sagand Department of Mining and Metallurgical Engineering Faculty of EngineeringYazd UniversityYazdIran School of Mining Engineering College of EngineeringUniversity of TehranTehranIran

Heterogeneous brittle geomaterials are highly susceptible to cyclic *** contain inherent flaws and cracks that grow under fatigue loads and lead to *** study presents a numerical model for analyzing fatigue in these materials based on the two-dimensional(2D)boundary element method and linear elastic fracture *** process is formulated by coupling the displacement discontinuity method with the incorporation technique of dissimilar regions and the governing equations of *** heterogeneous media are assumed to consist of materials with different properties,and the interfaces are assumed to be completely *** addition,the domains include multiple cracks exposed to constant and variable amplitude cyclic *** stress intensity factor is a crucial parameter in fatigue analysis,which is determined using the displacement field around crack *** incremental crack growth scheme is applied to calculating the fatigue *** growth rate values are employed to estimate the length of crack extension when there are multiple *** interaction between cracks is considered,which also includes the coalescence ***,various structures under different cyclic loads are examined to evaluate the accuracy of this *** results demonstrate the efficiency of the proposed approach in modeling fatigue crack growth and life *** behavior of life curves for the heterogeneous domain was as *** curves illustrate the breakpoints caused by utilizing discrete incremental life *** these points,the trend of the curves changed with the material properties and fatigue characteristics of the new material around the crack tips.

关键词： Fatigue life Crack coalescence Interface Incorporation technique Variable amplitude loading

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

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

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

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

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

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Integrative Medicine 2023年第4期21卷 354-360页

作者： Amir mohammad Jaladat Mahdi alizadeh Vaghasloo Fatemeh Atarzadeh mohammad Hossein Ayati Amir Hooman Kazemi Emine Akin mohammad Hashem Hashempur Department of Persian Medicine School of MedicineShiraz University of Medical SciencesShiraz ***Iran Department of Traditional Medicine School of Persian MedicineTehran University of Medical SciencesTehran ***Iran Department of History of Medicine School of Traditional MedicineTehran University of Medical SciencesTehran ***Iran International School Beijing University of Chinese MedicineBeijing 100029China Alkali Life Center Healthy Life&Consultancy and EducationAtas ehir-Istanbul 34750Turkey Research Center for Traditional Medicine and History of Medicine Department of Persian MedicineSchool of MedicineShiraz University of Medical SciencesShiraz ***Iran

Kaiy(medieval cautery)is an ancient method of heat therapy in traditional Persian medicine(TPM).Some of its important applications have been neglected during the medical ***,different treatment modalities that incorporate heat,including moxibustion,have progressed in traditional Chinese *** this study,we reviewed the main TPM textbooks that were written specifically in the field of *** considered the traditional teachings in the context of contemporary information,gathered from the scientific literature about moxibustion and modern *** surgical therapeutic indications of kaiy(e.g.,debridement and coagulative procedures)have been advanced by the innovation of ***,those therapeutic applications that were based on the TPM humoral theory for relieving body coldness or myofascial pains—which are similar to moxibustion usages—have not received the same *** from the broad similarities of kaiy and moxibustion as thermal therapies with similar indications,there is a striking correspondence between kaiy point mapping and ***,further research on different kaiy aspects is recommended.

关键词： Traditional Persian medicine Moxibustion Chinese medicine Kaiy Medieval cautery Fire acupuncture

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

在线全文

学校读者我要写书评

暂无评论

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

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

在线全文

学校读者我要写书评

暂无评论

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