检索结果-南通市图书馆

Transactions of Nonferrous Metals Society of China 2018年第9期28卷 1755-1762页

作者： M.AMIRNEJAD M.rajabi A.MOTAVALLI Department of Materials Science and Engineering Faculty of Mechanical EngineeringBabol Noshirvani University of TechnologyP.O.Box 47148-71167Shariati StreetBabolIran

The Mg-6Al-4Zn alloy was fabricated by mechanical alloying(MA)and hot pressing to serve as biodegradable metal *** influence of addition of 1%Si(mass fraction)on the microstructure,mechanical properties and bio-corrosion behavior of Mg-6Al-1Zn alloy was studied using X-ray diffractometry,transmission electron microscopy,compression test,as well as immersion,electrochemical test and MTT *** results showed that the addition of 1%Si to Mg-6Al-1Zn alloy led to the formation of fine Mg2Si phase with polygonal shape,and increased compressive strength,elongation and improved corrosion ***,the cell viability of Saos-2 cells has been improved by addition of 1%Si to Mg-6Al-1Zn *** to the results,the magnesium ions released in the methylthiazol tetrazolium(MTT)test have not shown any cell *** these indicated that the addition of 1%Si improved the properties of Mg-6Al-4Zn alloy for using as a biodegradable implant.

关键词： Mg-based alloy mechanical alloying mechanical properties corrosion rate cell viability

维普期刊数据库

Effect of extrusion speed on properties of Cu-5 vol.%TiSnC composite wire fabricated by friction stir back extrusion process

在线全文

学校读者我要写书评

暂无评论

Transactions of Nonferrous Metals Society of China 2023年

作者： Amirhossein JAHANI Hamed JAMSHIDI AVAL Mohammad rajabi Roohollah JAMAATI Department of Materials Engineering， Babol Noshirvani University of Technology

The present work investigated the effect of axial traverse speed of friction stir back extrusion (FSBE) process on the microstructure， mechanical， electrical， and wear properties of Cu-Ti2SnC composite wire. The FSBE process was performed on the primary composite made by the powder metallurgy method with 5 vol.% of Ti2SnC MAX phase. The results showed that as the extrusion speed increased， the twins formed in the microstructure increased， the Ti2SnC particles became finer， and the interface of bonding of the MAX phase-Cu matrix improved. The Cu-Ti2SnC composite wire fabricated by the rotational speed of 600 rpm and axial traverse speed of 25 mm/min showed maximum hardness， yield strength， and ultimate tensile strength of 132.7 HV， 278.3， and 485.1 MPa， respectively. This finding was due to its stronger interfacial bonding and finer MAX phase particles. Besides， the larger grain size， better interface bonding， and lower porosity resulted in the highest electrical conductivity of 89.21% IASC and least wear rate of 0.0015 mg/m of Cu-Ti2SnC composite wire fabricated by 600 rpm rotational speed and 25 mm/min axial traverse speed.

关键词：

A survey of incidental ocular trauma by pencil and pen

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

International Journal of Ophthalmology(English edition) 2018年第10期11卷 1668-1673页

作者： Seyed Ali Tabatabaei Mohammad Soleimani Morteza Naderan Aliasghar Ahmadraji Mohammad Bagher rajabi Hajar Jafari Mona Safizade Department of Ophthalmology Eye Research Center Farabi Eye Hospital Tehran University of Medical Sciences

AIM：To determine characteristic features of ocular trauma resulted from self-trauma by writing instruments among pediatric ***：Thirty-six children who suffered from selfinflicted ocular trauma with a writing instrument were included in this prospective cross-sectional ***：The mean age was 5.6±2.7y with male：female ratio of *** right eye was involved two times more than the left *** superomedial（55.5%）and inferomedial（30.6%）quadrants were the most common sites of *** leading culprit was colored pencils（44.4%）.During surgical exploration,no foreign body（FB）was found in 25（69.4%）patients while an FB was found in 11（30.5%）*** injury was present in two patients（5.6%）and only in superomedial quadrant *** 1 was the most common site for ocular trauma associated with penetrating *** mean ocular trauma score（OTS）in penetrating injuries was 3.8±*** best corrected visual acuity（BCVA）was 0.3±0.6 upon admittance and 0.08±0.21 after one *** final BCVA was significantly correlated with the entrance site,better final BCVA was found in nasal entrance site（P〈0.05）.CONCLUSION：The ophthalmologists should keep a high index of suspicion to rule out penetrating eye injuries related to writing instruments in a young uncooperative *** injury is a life-threatening event that should be ruled out by appropriate *** canthal area as the most common site needs an especial attention in writing instrument injuries.

关键词： pencil pediatric children trauma ocular

Germline cells derived from mesenchymal stem cells, with the focus on Wharton's jelly

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Asian pacific Journal of Reproduction 2018年第2期7卷 49-55页

作者： Hossein Yazdekhasti Jalil Hosseini Zahra rajabi Maryam Hosseinzadeh Shirzeyli Fereshte Aliakbari Department of Cell Biology Center for Research in Contraceptive and Reproductive HealthUniversity of VirginiaCharlottesvilleVA22908USA Infertility and Reproductive Health Research Center Shahid Beheshti University of Medical SciencesTehranIran Department of Anatomy School of MedicineTehran University of Medical SciencesTehranIran Department of Biomedical Engineering University of VirginiaCharlottesvilleVA22908USA Department of Biology and Anatomical Sciences School of MedicineShahid Beheshti University of Medical SciencesTehranIran

Previous attempts have indicated that mesenchymal stem cells (MSCs) are a valuable source and candidate and new approach for tissue engineering and reproductive medicine. MSCs have this potential to be induced and differentiated in an appropriatein vivoandin vitro condition toward various cell lineages and then they can be applied in cell therapies and clinical applications. During recent two decades, various sources have demonstrated they are a great source for MSCs, including bone marrow, the human umbilical cord as well as Wharton's jelly. Due to discarding after birth, easily accessible cells and less ethical concerns, these cells have attracted more and more scientists' attention. Infertility and reproduction diseases have provided special opportunity to examine the efficiency of MSCs in this kind of application. Based on recent investigations, MSCs embedded in Wharton's jelly tissue are more appealing for cell therapies, especially in infertility treatment purposes. So, differentiation of MSCs embedded in Wharton's jelly tissue into germ layer cells for cell-based therapy purposes is now under intensive study.

关键词： Mesenchymal stem cell Bone marrow stem cell Umbilical cord Wharton's jelly

Tribological behavior of friction stir processed SiP/ZA40 in-situ composites

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Transactions of Nonferrous Metals Society of China 2020年第11期30卷 3043-3057页

作者： F.rajabi R.TAGHIABADI M.H.SHAERI Department of Materials Science and Metallurgy Imam Khomeini International University(IKIU)QazvinIran

The effect of friction stir processing(FSP)at different rotation speeds(400,630,800,and 1000 r/min)and traverse speeds(25 and 50 mm/min)on the tribological properties of a Si particle reinforced Zn−40Al−2Cu-based in-situ composite was *** preliminary optimization,800 r/min and 25 mm/min were selected as optimum FSP *** to the results,multi-pass FSP improved the tribological *** instance,at an applied pressure of 0.75 MPa,the wear rate and average coefficient of friction(COF)of four-pass FSPed composite were lower than those of base composite by 53%and 50%,*** examinations of worn surfaces,wear debris,and worn subsurfaces revealed that the intensive refinement and uniform distribution of microstructural phases,especially the coarse Si particles,reduced Si particles interspacing,and elimination of casting defects were the most important factors enhancing the substrate resistance against sliding-induced *** led to the formation of stable tribolayers that improved the tribological properties.

关键词： Zn−40Al−2Cu alloy silicon composite tribology friction stir processing

维普期刊数据库

Line-start permanent magnet synchronous motors versus induction motors： A comparative study

在线全文

学校读者我要写书评

暂无评论

Frontiers of Electrical and Electronic Engineering in China 2012年第4期7卷 459-466页

作者： Majid Ghasemi KAHRISANGI Arash Hassanpour ISFAHANI Sadegh VAEZ-ZADEH Mohammad rajabi SEBDANI SAMA Technical and Vocational College Islamic Azad UniversityKhomeinishahr Branch Isfahan Iran Department of Engineering Islamic Azad University KhomeinishahrBranch Isfahan Iran School of Electrical and Computer Engineering University of TehranTehran Iran Department of'Engineering Islamic Azad University Harand BranchIsfahan Iran

Line-start permanent magnet synchronous motors are suitable candidates for substitution of induction motors in many constant-speed applications. This paper compares steady-state and dynamic performances of these motors. The efficiency, power factor, stator currents, and rotor bars currents are considered for steady-state perfor- mance analysis whereas the rotor speed, electromagnetic torque, and stator and rotor currents are investigated for dynamic performance analysis. For this purpose, time stepping finite element method is used to analyze the performance of motors in both full-load and no-load conditions. Results demonstrate the superior performance of the line-start permanent magnet synchronous motor in steady-state condition and the improved dynamic perfor-mance of the induction motor. Finally, economic calcula- tions indicate that the extra cost of the line-start permanent magnet synchronous motor with respect to the induction motor is rapidly compensated by energy saving due to a more efficient operation.

关键词： line-start permanent magnet synchronous

Effect of bariatric surgery on adiposity and metabolic profiles: A prospective cohort study in Middle-Eastern patients

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Diabetes 2017年第7期8卷 374-380页

作者： Mohsen Mazidi Peyman Rezaie Ali Jangjoo Alireza Tavassoli Mohammad Taghi rajabi Andre Pascal Kengne Mohsen Nematy Key State Laboratory of Molecular Develo-pmental Biology Institute of Genetics and Developmental Biology Chinese Academy of Sciences Institute of Genetics and Developmental Biology International College University of Chinese Academy of Science Biochemistry and Nutrition Research Center School of Medicine Mashhad University of Medical Science Department of Surgery Ghaem Hospital Mashhad University of Medical Sciences Non--Communicable Disease Research Unit South African Medical Research Council and University of Cape Town

AIM To investigate changes in adiposity and cardio-metabolic risk profile following Roux-en-Y gastric bypass in patients of Middle Eastern ethnicity with severe *** This prospective cohort study involved 92 patients who met the indications of bariatric surgery. Post-procedure markers of obesity and cardiometabolic profile were monitored regularly for a *** Mean body mass index decreased by 29.5% from 41.9 to 29.5 kg/m^2 between baseline and 12-mo follow-up, while mean fat mass decreased by 45.9% from 64.2 kg to 34.7 kg. An improvement was also observed in the glucometabolic profile with both fasting glucose and HbA 1csubstantially decreasing(P < 0.001).CONCLUSION The present study shows the short to medium term(1 year) health benefits of bariatric surgery for patients of Middle Eastern ethnicity.

关键词： Bariatric surgery Anthropometric indices Metabolic profile Cardiometabolic risk

Ultrasonographic visualization of lower eyelid structures and dynamic motion analysis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Ophthalmology(English edition) 2013年第5期6卷 592-595页

作者： Mohammad Taher rajabi Konstantinos Papageorgiou Shu-Hong Chang Imran Jarullazada Mehryar Taban Catherine J.Hwang Robert Alan Goldberg Division of Orbital and Ophthalmic Plastic Surgery Jules Stein Eye InstituteUniversity of California-Los Angeles Eye Research Center Farabi Eye HospitalTehran University of Medical Sciences

AIMTo define the ultrasonographic structure of normal lower eyelid anatomic compartments and their spacial relationship in dynamic motion.

关键词： lower eyelid ultrasonography dynamic motion analysis

Presentation of Design Equations for Array of Circumferential Slot on Cylindrical Waveguide

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Open Journal of Antennas and Propagation 2017年第4期5卷 180-187页

作者： Ali Khayati Amir Amirabadi Behnam rajabi Islamic Azad University Parand Branch Parand Iran Islamic Azad University South Tehran Branch Tehran Iran Islamic Azad University Tuyserkan Branch Tuyserkan Iran

In this paper the design equations for an array of circumferential slots on a cylindrical waveguide are obtained, following the procedure introduced by Elliott for slots on rectangular waveguides. The minimization of the error function is achieved for optimization of slot array parameters. The optimization of slot parameters is not goal of this paper but a numerical example are presented as illustrations of the proposed synthesis method. The results of array designs by the method of the least squares are verified by two computer simulation softwares, namely CST and HFSS.

关键词： Array Slot Arrays Cylindrical Waveguide Slot Array Cylindrical Waveguide Circumferential Slot Array Design Equations

Thermal stability of nanocrystalline Mg-based alloys prepared via mechanical alloying

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Transactions of Nonferrous Metals Society of China 2016年第2期26卷 398-405页

作者： M.rajabi R.M.SEDIGHI S.M.RABIEE Department of Material Science and Engineering Faculty of Mechanical EngineeringBabol Noshirvani University of Technology

Thethermal stability and the kinetics of grain growth of nanocrystalline Mg-6Al-1Zn and Mg-6Al-1Zn-1Si alloys prepared via mechanical alloying were investigated. It started with elemental powders, using a variety of analytical techniques including differential scanning calorimetry （DSC）, X-ray diffraction （XRD）, scanning electron microscopy （SEM）, transmission electron microscopy （TEM） and energy dispersive spectrometry. The kinetics of grain growth in isothermal annealing was investigated. The XRD results show that, although the grain sizes of both material systems increase as the annealing temperature rises, the Si-containing system displays a relatively smaller grain size, i.e., 60 nm compared with 72 nm in Mg-6Al-1Zn system, after being exposed to 350 ℃ for 1 h. The second-phase intermetallic particle Mg2Si formed during the isothermal annealing of Mg-6Al-1Zn-1Si system could influence not only the activation energy but also the exponent of kinetic equation. Higher hardness values obtained in the Si-containing system would be due to the formation of Mg2Si intermetallic phase.

关键词： Mg-based alloys thermal stability grain growth mechanical alloying

维普期刊数据库