Pub Date : 2021-02-01DOI: 10.47176/jame.39.4.15152
S. S. Shafiei, M. Shavandi, Y. Nickakhtar
Tissue-engineering scaffolds provide biological and mechanical frameworks for cell adhesion, growth, and differentiation. Nanofibrous scaffolds mimic the native extracellular matrix (ECM) and play a significant role in formation and remodeling of tissues and/or organs . One way to mimic the desired properties of fibrous ECM is adding nanoparticles into the polymer matrix. In the current study, the uniform fibers of poly (ε-caprolactone) (PCL) enriched with different layered double hydroxide (LDH) contents (ranging from 0.1 wt.% to 10 wt.%) were successfully fabricated by electrospinning method. The LDH * :یکینورتکلا تسپ ،تابتاکم لوئسم : shafiei@nigeb.ac.ir D ow nl oa de d fr om ja m e. iu t.a c. ir at 1 2: 46 IR D T o n F rid ay M ay 2 8t h 20 21 یعیفش و ناراکمه تسبراد تایصوصخ رب سرونان ندوزفا رثا یسررب ... 46 ،یسدنهم رد هتفرشیپ داوم لاس 39 رامش ، ه 4 ، ناتسمز 1399 nano particles were randomly dispersed in the fibers, as confirmed by Energy Dispersive X-ray analysis (EDX). Scaffolds were analyzed from morphological, physical and mechanical view. Biological assessments of scaffolds in terms of cellular attachment and adipogenic differentiation of mouse adipose derived stem cells (mADSCs) were performed. The results showed that inclusion of LDH nanoparticles reduced the average fiber diameter and enhanced the tensile strength and elongation at break values of the PCL scaffold. The LDH-enriched electrospun PCL scaffolds had remarkable effects on cell adhesion. Moreover, a significant increase in adipogenic differentiation of mADSCs was observed. The PCL/LDH nanofibrous scaffolds showed great potential in application for soft tissue engineering.
组织工程支架为细胞粘附、生长和分化提供了生物学和力学框架。纳米纤维支架模拟天然细胞外基质(ECM)，在组织和/或器官的形成和重塑中发挥重要作用。一种模拟纤维ECM所需性能的方法是将纳米颗粒添加到聚合物基体中。本研究采用静电纺丝法，成功制备了含有不同层状双氢氧化物(LDH)含量(0.1 wt.% ~ 10 wt.%)的聚ε-己内酯(PCL)均匀纤维。LDH *:یکینورتکلاتسپ،تابتاکملوئسم:shafiei@nigeb.ac.ir噢问oa de D fr om ja m e . iu t.a c .红外1 2:46红外D T o n F掉ay m ay 2 8 T h 20 21یعیفشوناراکمهتسبرادتایصوصخربسرونانندوزفارثایسررب……通过能量色散x射线分析(EDX)，证实了46 ،یسدنهم رد هتفرشیپ داوم لاس 39 رامش， 4， ناتسمز 1399纳米颗粒随机分散在纤维中。从形态、物理和力学角度对支架进行了分析。从细胞附着和小鼠脂肪干细胞(mADSCs)的成脂分化方面对支架进行了生物学评估。结果表明，LDH纳米颗粒的加入降低了PCL支架的平均纤维直径，提高了其抗拉强度和断裂伸长率。富ldh静电纺PCL支架对细胞粘附有显著影响。此外，我们还观察到mADSCs的成脂分化显著增加。PCL/LDH纳米纤维支架在软组织工程中具有广阔的应用前景。
{"title":"Effect of Nanoclay Addition on the Properties of Polycaprolactone Nanocomposite Scaffolds Containing Adipose Derived Mesenchymal Stem Cells used in Soft Tissue Engineering","authors":"S. S. Shafiei, M. Shavandi, Y. Nickakhtar","doi":"10.47176/jame.39.4.15152","DOIUrl":"https://doi.org/10.47176/jame.39.4.15152","url":null,"abstract":"Tissue-engineering scaffolds provide biological and mechanical frameworks for cell adhesion, growth, and differentiation. Nanofibrous scaffolds mimic the native extracellular matrix (ECM) and play a significant role in formation and remodeling of tissues and/or organs . One way to mimic the desired properties of fibrous ECM is adding nanoparticles into the polymer matrix. In the current study, the uniform fibers of poly (ε-caprolactone) (PCL) enriched with different layered double hydroxide (LDH) contents (ranging from 0.1 wt.% to 10 wt.%) were successfully fabricated by electrospinning method. The LDH * :یکینورتکلا تسپ ،تابتاکم لوئسم : shafiei@nigeb.ac.ir D ow nl oa de d fr om ja m e. iu t.a c. ir at 1 2: 46 IR D T o n F rid ay M ay 2 8t h 20 21 یعیفش و ناراکمه تسبراد تایصوصخ رب سرونان ندوزفا رثا یسررب ... 46 ،یسدنهم رد هتفرشیپ داوم لاس 39 رامش ، ه 4 ، ناتسمز 1399 nano particles were randomly dispersed in the fibers, as confirmed by Energy Dispersive X-ray analysis (EDX). Scaffolds were analyzed from morphological, physical and mechanical view. Biological assessments of scaffolds in terms of cellular attachment and adipogenic differentiation of mouse adipose derived stem cells (mADSCs) were performed. The results showed that inclusion of LDH nanoparticles reduced the average fiber diameter and enhanced the tensile strength and elongation at break values of the PCL scaffold. The LDH-enriched electrospun PCL scaffolds had remarkable effects on cell adhesion. Moreover, a significant increase in adipogenic differentiation of mADSCs was observed. The PCL/LDH nanofibrous scaffolds showed great potential in application for soft tissue engineering.","PeriodicalId":30992,"journal":{"name":"Journal of Advanced Materials in Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70774017","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2021-02-01DOI: 10.47176/jame.39.4.19662
S. N. Hosseini, F. Karimzadeh, M. Enayati
The bare and pre-oxidized AISI 430 pieces were screen printed by copper ferrite spinel coatings. Good bonding between the coating and the substrate was achieved by the reactive sintering process of the reduced coating. The energy dispersive * :یکینورتکلا تسپ ،تابتاکم لوئسم : n.hosseini@pgu.ac.ir D ow nl oa de d fr om ja m e. iu t.a c. ir at 3 :5 7 IR D T o n T hu rs da y A ug us t 5 th 2 02 1 [ D O I: 10 .4 71 76 /ja m e. 39 .4 .1 96 62 ] ینیسح ناراکمه و دلاوف يور سم تیرف یلنیپسا ششوپ داجیا AISI430 يارب ... 24 لاس ،یسدنهم رد هتفرشیپ داوم 39 رامش ، ه 4 ، ناتسمز 1399 X-ray spectroscopy (EDS) analysis revealed that the scale is a double layer consisting of a chromia-rich subscale and an outer Cu/Fe-rich spinel. The results showed that the spinel protection layer not only significantly decreased the area specific resistance (ASR), but also inhibited the subscale growth by acting as a barrier to the inward diffusion of oxygen. ASRs of 19.7 and 32.5 mΩ.cm2, much lower than that of the bare substrate (153.4 mΩ.cm2), at 800 °C after 400 h oxidation were achieved for the bare and pre-oxidized copper ferrite spinel coated samples, respectively. Excellent, stable ASR (20.5 mΩ.cm) was obtained with copper ferrite coating after 600 h of exposure at 800 °C. The high electrical conductivity of CuFe2O4 and its doping by Mn, the growth reduction of Cr2O3 oxide scale and the good coating to substrate adherence are proposed to be responsible for substantial improvement in electrical conductivity.
裸露的和预氧化的AISI 430片通过铜-铁氧体-尖晶石涂层丝网印刷。通过还原涂层的反应烧结工艺实现了涂层与基体之间的良好结合。能量色散*：n.hosseini@pgu.ac.irD ow nl oa de D fr om ja m e.iu t.a c.ir at 3:5 7 ir D t o n t hu rs da y a ug us t t t 5 th 2 02 1[D o I:10.4 71 76/ja m e.39.4 96 62]یی。。。24لابیدن1607;مرد㻫تٕا1740پ1583او1605;。结果表明，尖晶石保护层不仅显著降低了面积比电阻（ASR），而且作为氧气向内扩散的屏障，抑制了亚尺度生长。在800°C下，经过400小时氧化后，裸露和预氧化的铜-铁氧体-尖晶石涂层样品的ASR分别为19.7和32.5 mΩ/cm2，远低于裸露衬底的ASR（153.4 mΩ.cm2）。在800°C下暴露600小时后，铜铁氧体涂层获得了优异、稳定的ASR（20.5 mΩ.cm）。CuFe2O4的高电导率及其Mn掺杂、Cr2O3氧化皮的生长减少以及涂层与基体的良好粘附性被认为是电导率显著提高的原因。
{"title":"Development of Copper-Ferrite Spinel Coating on AISI 430 Steel Used as Solid Oxide Fuel Cell","authors":"S. N. Hosseini, F. Karimzadeh, M. Enayati","doi":"10.47176/jame.39.4.19662","DOIUrl":"https://doi.org/10.47176/jame.39.4.19662","url":null,"abstract":"The bare and pre-oxidized AISI 430 pieces were screen printed by copper ferrite spinel coatings. Good bonding between the coating and the substrate was achieved by the reactive sintering process of the reduced coating. The energy dispersive * :یکینورتکلا تسپ ،تابتاکم لوئسم : n.hosseini@pgu.ac.ir D ow nl oa de d fr om ja m e. iu t.a c. ir at 3 :5 7 IR D T o n T hu rs da y A ug us t 5 th 2 02 1 [ D O I: 10 .4 71 76 /ja m e. 39 .4 .1 96 62 ] ینیسح ناراکمه و دلاوف يور سم تیرف یلنیپسا ششوپ داجیا AISI430 يارب ... 24 لاس ،یسدنهم رد هتفرشیپ داوم 39 رامش ، ه 4 ، ناتسمز 1399 X-ray spectroscopy (EDS) analysis revealed that the scale is a double layer consisting of a chromia-rich subscale and an outer Cu/Fe-rich spinel. The results showed that the spinel protection layer not only significantly decreased the area specific resistance (ASR), but also inhibited the subscale growth by acting as a barrier to the inward diffusion of oxygen. ASRs of 19.7 and 32.5 mΩ.cm2, much lower than that of the bare substrate (153.4 mΩ.cm2), at 800 °C after 400 h oxidation were achieved for the bare and pre-oxidized copper ferrite spinel coated samples, respectively. Excellent, stable ASR (20.5 mΩ.cm) was obtained with copper ferrite coating after 600 h of exposure at 800 °C. The high electrical conductivity of CuFe2O4 and its doping by Mn, the growth reduction of Cr2O3 oxide scale and the good coating to substrate adherence are proposed to be responsible for substantial improvement in electrical conductivity.","PeriodicalId":30992,"journal":{"name":"Journal of Advanced Materials in Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49461756","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-01DOI: 10.47176/jame.39.3.18761
M. T. A. Khanouki
In this study, the influence of temperature and strain rate on plastic flow of a Zr-based bulk metallic glass (BMG) during the three-point bending test was studied to find a correlation between strain rate sensitivity (m) and flow behavior. The flexural stress-deflection curves revealed two distinct types of dynamics, serrated and non-serrated flow, related to temperature and strain rate. The serrated flow which appeared at temperatures higher than a critical value or strain rates lower than a critical value, was simultaneously due to activation of shear transformation zones (STZs) and time-dependent structural relaxations. Further results indicated negative and positive values of m at temperatures above and below 0.4 Tg, respectively. The main reason for negative strain rate sensitivity was insufficient time of structural relaxation at high strain rates which lead to generation of free volume inside shear bands making the BMG softer. Comparison of STZ activation energy with activation energy for the onset of serration indicated almost equal values and there was a close relationship between serrated flow and STZ operation.
{"title":"Effect of Temperature and Strain Rate on Plastic Deformation Behavior of Zr46(Cu4.5/5.5Ag1/5.5)46Al8 Bulk Metallic Glass","authors":"M. T. A. Khanouki","doi":"10.47176/jame.39.3.18761","DOIUrl":"https://doi.org/10.47176/jame.39.3.18761","url":null,"abstract":"In this study, the influence of temperature and strain rate on plastic flow of a Zr-based bulk metallic glass (BMG) during the three-point bending test was studied to find a correlation between strain rate sensitivity (m) and flow behavior. The flexural stress-deflection curves revealed two distinct types of dynamics, serrated and non-serrated flow, related to temperature and strain rate. The serrated flow which appeared at temperatures higher than a critical value or strain rates lower than a critical value, was simultaneously due to activation of shear transformation zones (STZs) and time-dependent structural relaxations. Further results indicated negative and positive values of m at temperatures above and below 0.4 Tg, respectively. The main reason for negative strain rate sensitivity was insufficient time of structural relaxation at high strain rates which lead to generation of free volume inside shear bands making the BMG softer. Comparison of STZ activation energy with activation energy for the onset of serration indicated almost equal values and there was a close relationship between serrated flow and STZ operation.","PeriodicalId":30992,"journal":{"name":"Journal of Advanced Materials in Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70774264","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-01DOI: 10.47176/jame.39.2.21621
M. Etminan, M. Morakabati, Sayyed mahdi Qazi mir saeid
The aim of this study was to investigate the effect of temperature and time of homogenization treatment on the microstructure, distribution of alloying elements and hardness of the novel Co-based superalloy Co-7Al-7W-4Ti-2Ta. For this purpose, the specimens were first homogenized at 1250 and 1300 °C for 2, 4, 6 and 8 hours and then water-cooled. Subsequently, the specimens were subjected to hardness testing and microstructural examinations by optical and electron microscopy. The * یکینورتکلا تسپ ،تابتاکم لوئسم : : m_morakabati@mut.ac.ir D ow nl oa de d fr om ja m e. iu t.a c. ir at 4 :0 7 IR S T o n W ed ne sd ay D ec em be r 30 th 2 02 0 [ D O I: 10 .4 71 76 /ja m e. 39 .2 .2 16 21 ]
研究了均匀化处理温度和时间对新型co基高温合金Co-7Al-7W-4Ti-2Ta显微组织、合金元素分布和硬度的影响。为此，首先将样品在1250和1300°C下均质2、4、6和8小时，然后水冷。随后，用光学显微镜和电子显微镜对试样进行硬度测试和显微组织检查。*یکینورتکلاتسپ،تابتاکملوئسم::m_morakabati@mut.ac.ir噢问oa de D fr om ja m e . iu t.a c .红外4:0 7 ir S T o n W ed ne sd ay D ec em是30 th 2 2 0 r (D o我:71 76 / ja m e。39。4。2。2 16 21)
{"title":"Investigation of the Effect of Homogenization Treatment on Distribution of Alloying Elements, Microstructure and Hardness of Co-Al-W-Ti-Ta-Base Superalloy","authors":"M. Etminan, M. Morakabati, Sayyed mahdi Qazi mir saeid","doi":"10.47176/jame.39.2.21621","DOIUrl":"https://doi.org/10.47176/jame.39.2.21621","url":null,"abstract":"The aim of this study was to investigate the effect of temperature and time of homogenization treatment on the microstructure, distribution of alloying elements and hardness of the novel Co-based superalloy Co-7Al-7W-4Ti-2Ta. For this purpose, the specimens were first homogenized at 1250 and 1300 °C for 2, 4, 6 and 8 hours and then water-cooled. Subsequently, the specimens were subjected to hardness testing and microstructural examinations by optical and electron microscopy. The * یکینورتکلا تسپ ،تابتاکم لوئسم : : m_morakabati@mut.ac.ir D ow nl oa de d fr om ja m e. iu t.a c. ir at 4 :0 7 IR S T o n W ed ne sd ay D ec em be r 30 th 2 02 0 [ D O I: 10 .4 71 76 /ja m e. 39 .2 .2 16 21 ]","PeriodicalId":30992,"journal":{"name":"Journal of Advanced Materials in Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41530418","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-01DOI: 10.47176/jame.39.2.22191
A. Ghasemi, M. L. Estarki, S. Torkian, G. Gordani
: The purpose of this study was to evaluate phase changes and magnetic properties of neodymium doped Ni 0.7 Zn 0.3 Nd x Fe 2-x O 4 (x = 0, 0.01, 0.03, 0.05, 0.07, 0.10) nanoparticles synthesized by complexing sol-gel method. In this method, triethanolamine (TEA) acted as both a gelling agent and a chelating agent. Samples were characterized by X-ray diffraction (XRD) analysis, field emission scanning electron microscopy (FESEM), and energy dispersive X-ray spectroscopy (EDX). XRD patterns of all synthesized samples revealed the formation of a spinel ferrite phase. Magnetic evaluation of the specimens showed that the Nd 0.01 doped sample with a quasi-spherical morphology and particle size of about 60 nm has the highest saturation magnetization of 50 emu/g and coercive force of 103 Oe.
{"title":"Effect of Neodymium Dopping on Morphology, Phase Changes and Magnetic Properties of Ni0.7Zn0.3NdxFe2-xO4 Ferrite Nanoparticles Synthesized by Complexing Sol-Gel Method","authors":"A. Ghasemi, M. L. Estarki, S. Torkian, G. Gordani","doi":"10.47176/jame.39.2.22191","DOIUrl":"https://doi.org/10.47176/jame.39.2.22191","url":null,"abstract":": The purpose of this study was to evaluate phase changes and magnetic properties of neodymium doped Ni 0.7 Zn 0.3 Nd x Fe 2-x O 4 (x = 0, 0.01, 0.03, 0.05, 0.07, 0.10) nanoparticles synthesized by complexing sol-gel method. In this method, triethanolamine (TEA) acted as both a gelling agent and a chelating agent. Samples were characterized by X-ray diffraction (XRD) analysis, field emission scanning electron microscopy (FESEM), and energy dispersive X-ray spectroscopy (EDX). XRD patterns of all synthesized samples revealed the formation of a spinel ferrite phase. Magnetic evaluation of the specimens showed that the Nd 0.01 doped sample with a quasi-spherical morphology and particle size of about 60 nm has the highest saturation magnetization of 50 emu/g and coercive force of 103 Oe.","PeriodicalId":30992,"journal":{"name":"Journal of Advanced Materials in Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70774217","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-01DOI: 10.47176/jame.39.3.21681
M. Tavoosi
: The present work aims to modify surface properties of pure Ti by development of Ti-Al-N intermetallic composite coatings. In this regard, tungsten inert gas (TIG) cladding process was carried out using Al 1100 as filler rod with Ar and Ar+N 2 as shielding gases. Phase and structure of the samples were investigated by X-ray diffraction (XRD) technique, optical microscopy (OM) and scanning electron microscopy (SEM). Hardness values and corrosion behavior of the obtained coatings were also compared using Vickers microhardness tester and potentiostat, respectively. The results showed that composite structure containing Al 3 Ti, Ti 3 Al 2 N 2 and Ti 3 Al intermetallic compounds could be formed on the surface of pure Ti. Amounts of brittle phases and welding defects at the titanium-coating interface were least by welding under pure Ar shielding. Despite the increasing amount of structural defects such as porosity and non-uniformity under Ar+N 2 shielding, the prepared coatings had higher hardness (more than 100 HV) and corrosion resistance (more than twice) compared with those obtained under Ar shielding.
{"title":"Development of Al-Ti-N Composite Coatings on Commercially Pure Ti Surface by Tungsten Inert Gas Process","authors":"M. Tavoosi","doi":"10.47176/jame.39.3.21681","DOIUrl":"https://doi.org/10.47176/jame.39.3.21681","url":null,"abstract":": The present work aims to modify surface properties of pure Ti by development of Ti-Al-N intermetallic composite coatings. In this regard, tungsten inert gas (TIG) cladding process was carried out using Al 1100 as filler rod with Ar and Ar+N 2 as shielding gases. Phase and structure of the samples were investigated by X-ray diffraction (XRD) technique, optical microscopy (OM) and scanning electron microscopy (SEM). Hardness values and corrosion behavior of the obtained coatings were also compared using Vickers microhardness tester and potentiostat, respectively. The results showed that composite structure containing Al 3 Ti, Ti 3 Al 2 N 2 and Ti 3 Al intermetallic compounds could be formed on the surface of pure Ti. Amounts of brittle phases and welding defects at the titanium-coating interface were least by welding under pure Ar shielding. Despite the increasing amount of structural defects such as porosity and non-uniformity under Ar+N 2 shielding, the prepared coatings had higher hardness (more than 100 HV) and corrosion resistance (more than twice) compared with those obtained under Ar shielding.","PeriodicalId":30992,"journal":{"name":"Journal of Advanced Materials in Engineering","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70774323","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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