Thermoplastic elastomer-based fibers have many advantages including lightness, flexibility, resilience. Styrene-[ethylene-(ethylene-propylene)]-styrene (SEEPS) is a styrenic block copolymer based thermoplastic elastomer and it can be used for many applications with many functions as a matrix, compatibilizer, modifier or adhesive. It has good resistance to oxidizing agents, weathering, aging, and it can be used under various conditions. In this study, SEEPS block copolymer fibers were electrospun. This study is the first study about the electrospinning of SEEPS block copolymer in the literature. Various spinning solutions were used, and process was optimized by changing the electrospinning conditions. Fiber morphology was analyzed by an optical microscope and fiber diameter distribution histograms were drawn. In order to understand the effects of polymer concentration on electrospinning, viscosity of the spinning solutions was measured. Although electrospinning conditions were found to be critical in terms of spinnability, solution concentration and viscosity were the most significant factors for obtaining flexible SEEPS based fibrous nonwoven mats.
{"title":"Production of Styrene-[Ethylene-(Ethylene-Propylene)]-Styrene Block Copolymer (SEEPS) Microfibers by Electrospinning","authors":"O. Toprakci, M. S. Cetin, H. A. Karahan Toprakci","doi":"10.13005/msri/180104","DOIUrl":"https://doi.org/10.13005/msri/180104","url":null,"abstract":"Thermoplastic elastomer-based fibers have many advantages including lightness, flexibility, resilience. Styrene-[ethylene-(ethylene-propylene)]-styrene (SEEPS) is a styrenic block copolymer based thermoplastic elastomer and it can be used for many applications with many functions as a matrix, compatibilizer, modifier or adhesive. It has good resistance to oxidizing agents, weathering, aging, and it can be used under various conditions. In this study, SEEPS block copolymer fibers were electrospun. This study is the first study about the electrospinning of SEEPS block copolymer in the literature. Various spinning solutions were used, and process was optimized by changing the electrospinning conditions. Fiber morphology was analyzed by an optical microscope and fiber diameter distribution histograms were drawn. In order to understand the effects of polymer concentration on electrospinning, viscosity of the spinning solutions was measured. Although electrospinning conditions were found to be critical in terms of spinnability, solution concentration and viscosity were the most significant factors for obtaining flexible SEEPS based fibrous nonwoven mats.","PeriodicalId":18247,"journal":{"name":"Material Science Research India","volume":"47 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85741195","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}
Bacterial resistance to a wide spectrum of antimicrobial medicines has evolved as a major public health concern. Antibiotics are medications that are used to kill microorganisms that could cause serious illness or death. Nanotechnology has exploded as a significant and appealing field of research, with innovative features and functionalities in a variety of fields. Silver is a versatile antibacterial and anticancer medicinal agent in the form of nanoparticles. Silver Nanoparticles (AgNPs) have been implicated in a wide variety of medicinal benefits. This review article addresses antibacterial applications of biosynthesized AgNPsthat have been researched over the last decade. AgNPs' antimicrobial potential against a variety of bacterial agents is discussed.
{"title":"Antibacterial Applications of Biosynthesized AgNPs: A Short Review (2015-2020)","authors":"A. P. Patil, Kailas H. Kapadnis","doi":"10.13005/msri/180203","DOIUrl":"https://doi.org/10.13005/msri/180203","url":null,"abstract":"Bacterial resistance to a wide spectrum of antimicrobial medicines has evolved as a major public health concern. Antibiotics are medications that are used to kill microorganisms that could cause serious illness or death. Nanotechnology has exploded as a significant and appealing field of research, with innovative features and functionalities in a variety of fields. Silver is a versatile antibacterial and anticancer medicinal agent in the form of nanoparticles. Silver Nanoparticles (AgNPs) have been implicated in a wide variety of medicinal benefits. This review article addresses antibacterial applications of biosynthesized AgNPsthat have been researched over the last decade. AgNPs' antimicrobial potential against a variety of bacterial agents is discussed.","PeriodicalId":18247,"journal":{"name":"Material Science Research India","volume":"51 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80917833","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}
The study presents the research findings on electrical contact materials based on tungsten-copper (W-Cu) composites containing 72 ± 3 wt.% W, rest Cu, and up to 1.5 wt.% Ni. Cylindrical sintered parts with 57 ± 0.5 mm in diameter and 12 ± 0.5 mm in height were manufactured by pressing, sintering, and liquid infiltration route, then were mechanically polished and processed as complex shape protection rings used as arcing contacts in high voltage circuit breakers (HVCBs). The surface elemental composition of the sintered parts was determined by wavelength dispersive X-ray fluorescence spectrometry. The density was determined by hydrostatic weighing in ethanol. The arithmetic mean surface roughness was measured by contact profilometry. The microstructure was studied by scanning electron microscopy. The electrical conductivity was measured by eddy current method. The thermal diffusivity and specific heat were determined by laser flash analysis. Instrumented indentation testing and two computational methods (Oliver & Pharr, and Martens hardness) were employed to study the mechanical properties under quadratic loading and continuous multi cycle (CMC) indentation mode. The functional behavior of the arcing contacts was assessed in terms of static and dynamic contact resistance in operation in minimum oil HVCBs of 110 kV. The properties investigation revealed highly dense contact parts with homogeneous microstructure, Vickers hardness of 260-374, elastic modulus of 185-311 GPa, as well as good electrical and thermal conductivity. The arcing contacts proved a good functional behavior. in service, too. The results endorse the developed sintered contact materials for implementation in practical applications.
{"title":"Tungsten-Copper Composites for Arcing Contact Applications","authors":"Magdalena Valentina Lungu","doi":"10.13005/MSRI/170304","DOIUrl":"https://doi.org/10.13005/MSRI/170304","url":null,"abstract":"The study presents the research findings on electrical contact materials based on tungsten-copper (W-Cu) composites containing 72 ± 3 wt.% W, rest Cu, and up to 1.5 wt.% Ni. Cylindrical sintered parts with 57 ± 0.5 mm in diameter and 12 ± 0.5 mm in height were manufactured by pressing, sintering, and liquid infiltration route, then were mechanically polished and processed as complex shape protection rings used as arcing contacts in high voltage circuit breakers (HVCBs). The surface elemental composition of the sintered parts was determined by wavelength dispersive X-ray fluorescence spectrometry. The density was determined by hydrostatic weighing in ethanol. The arithmetic mean surface roughness was measured by contact profilometry. The microstructure was studied by scanning electron microscopy. The electrical conductivity was measured by eddy current method. The thermal diffusivity and specific heat were determined by laser flash analysis. Instrumented indentation testing and two computational methods (Oliver & Pharr, and Martens hardness) were employed to study the mechanical properties under quadratic loading and continuous multi cycle (CMC) indentation mode. The functional behavior of the arcing contacts was assessed in terms of static and dynamic contact resistance in operation in minimum oil HVCBs of 110 kV. The properties investigation revealed highly dense contact parts with homogeneous microstructure, Vickers hardness of 260-374, elastic modulus of 185-311 GPa, as well as good electrical and thermal conductivity. The arcing contacts proved a good functional behavior. in service, too. The results endorse the developed sintered contact materials for implementation in practical applications.","PeriodicalId":18247,"journal":{"name":"Material Science Research India","volume":"11 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89927649","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}
Single crystal of Thiourea Sodium Sulphate (TSS) was prepared by a slow evaporation technique. The optical absorption and absorption coefficient are studied by UV. Vis.-NIR The voids or defects of the TSS crystal were carried out by its surface morphology analysis by SEM. The NLO properties of shocked TSS single crystal were estimated by UV-Vis-NIR spectroscopic analysis. Finally the nonlinear optical property of TSS crystal was estimated by Second Harmonic Generation (SHG) and the suitability of present titled mono crystal against mechanical resistivity after the shock for non linear optics and for photonic application has been confirmed.
{"title":"Synthesis and Characterization of SEM, UV absorption coefficient and shock wave properties of Thiourea Sodium Sulphate crystal","authors":"M. Bhaskar, S. Senthilkumar, G. Shankar","doi":"10.13005/MSRI/170309","DOIUrl":"https://doi.org/10.13005/MSRI/170309","url":null,"abstract":"Single crystal of Thiourea Sodium Sulphate (TSS) was prepared by a slow evaporation technique. The optical absorption and absorption coefficient are studied by UV. Vis.-NIR The voids or defects of the TSS crystal were carried out by its surface morphology analysis by SEM. The NLO properties of shocked TSS single crystal were estimated by UV-Vis-NIR spectroscopic analysis. Finally the nonlinear optical property of TSS crystal was estimated by Second Harmonic Generation (SHG) and the suitability of present titled mono crystal against mechanical resistivity after the shock for non linear optics and for photonic application has been confirmed.","PeriodicalId":18247,"journal":{"name":"Material Science Research India","volume":"2 1","pages":"270-275"},"PeriodicalIF":0.0,"publicationDate":"2020-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78708052","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}
R. Naik, V. Revathi, H. Nagabhushana, K. Girish, H. P. Nagaswarupa
Low temperature solution combustion synthesized Cr3+(1- 4 mol%) doped Mg2SiO4 nanoparticles were analyzed by Powder X-ray Diffraction (PXRD), Fourier Transform Infra-Red (FTIR) spectroscopy, Cyclic voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS) techniques. PXRD profile shows the samples are crystalline.FTIR spectra show MgO6 octahedral and Si-O bending and stretching modes.It was observed that, CV show excellent semi rectangular shaped voltammograms due to the oxidation reduction reactions and the reversibility of the reaction which suits for electric double layer capacitance.Charge transfer resistance (Rct) was found to be 10 Ωindicates the better electron transfer from one phase to another.
{"title":"Cyclic voltammetry and electrochemical impedance spectroscopy analysis of Cr3+ doped Mg2SiO4 nanoparticles","authors":"R. Naik, V. Revathi, H. Nagabhushana, K. Girish, H. P. Nagaswarupa","doi":"10.13005/MSRI/170303","DOIUrl":"https://doi.org/10.13005/MSRI/170303","url":null,"abstract":"Low temperature solution combustion synthesized Cr3+(1- 4 mol%) doped Mg2SiO4 nanoparticles were analyzed by Powder X-ray Diffraction (PXRD), Fourier Transform Infra-Red (FTIR) spectroscopy, Cyclic voltammetry (CV) and Electrochemical Impedance Spectroscopy (EIS) techniques. PXRD profile shows the samples are crystalline.FTIR spectra show MgO6 octahedral and Si-O bending and stretching modes.It was observed that, CV show excellent semi rectangular shaped voltammograms due to the oxidation reduction reactions and the reversibility of the reaction which suits for electric double layer capacitance.Charge transfer resistance (Rct) was found to be 10 Ωindicates the better electron transfer from one phase to another.","PeriodicalId":18247,"journal":{"name":"Material Science Research India","volume":"15 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75674480","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}