Pub Date : 2019-04-01DOI: 10.13189/UJMS.2019.070201
Berhanu Aragie
We investigate the way of enhancing the optical third order susceptibility, the refractive index, and absorption coefficient of a composite media in which identical nonlinear nanospheres having double interfacial layer randomly embedded in the linear host medium. We observe two maxima peaks of the nonlinear properties. We also show that the effect of double interfacial layers on the third order susceptibility, the refractive index, and absorption coefficient depends on the volume fraction metal/ dielectric nanosphers and the nature of the double interfacial layers. Under appropriate condition (nature of the two interfacial layer) we found two maximum peaks of the nonlinear properties. We also compare with the same composite without interfacial layer and in the presence of single interfacial layer and our finding shows that because of additional interfacial layer the effective medium exhibit a better third-order susceptibility, refractive index, and absorption coefficient.
{"title":"Double Interfacial Layers Effect on Optical Third-order Nonlinear Susceptibility, Refraction Index, and Absorption Coefficient of a Metal/ Dielectric Composite","authors":"Berhanu Aragie","doi":"10.13189/UJMS.2019.070201","DOIUrl":"https://doi.org/10.13189/UJMS.2019.070201","url":null,"abstract":"We investigate the way of enhancing the optical third order susceptibility, the refractive index, and absorption coefficient of a composite media in which identical nonlinear nanospheres having double interfacial layer randomly embedded in the linear host medium. We observe two maxima peaks of the nonlinear properties. We also show that the effect of double interfacial layers on the third order susceptibility, the refractive index, and absorption coefficient depends on the volume fraction metal/ dielectric nanosphers and the nature of the double interfacial layers. Under appropriate condition (nature of the two interfacial layer) we found two maximum peaks of the nonlinear properties. We also compare with the same composite without interfacial layer and in the presence of single interfacial layer and our finding shows that because of additional interfacial layer the effective medium exhibit a better third-order susceptibility, refractive index, and absorption coefficient.","PeriodicalId":375998,"journal":{"name":"Universal Journal of Materials Science","volume":"47 3","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114033158","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 : 2019-01-01DOI: 10.13189/UJMS.2018.070101
H. Zengin, H. Ahlatçı, Serafettin Oner, Mustafa Emre Demirkazik, S. Ozcelik, Y. Turen, Yavuz Sun
Heat treatment is the most commonly used production step which can change the overall mechanical properties of the material without changing the chemical composition. Among the heat treatment methods, accelerated cooling has been regarded as one of the most important method for obtaining good mechanical properties. Today, this method is used in the manufacture of thin pearlitic steel, double phase steel, bainitic steel in the production process of many different quality and size products from construction bar to profile. In the scope of this study, investigations were carried out on S355J2 equal angles section profiles produced by hot rolling method. It was observed that intensive inclusions were found in all of the materials and the mechanical strength could not be met at low rolling ratios. Particularly, these materials with low impact resistance have been subjected to accelerated cooling process in order to increase their impact strength. As a result of the accelerated cooling process, significant increases in impact strength have been observed, particularly with the change of microstructure.
{"title":"The Effect of Accelerated Cooling on Microstructure and Impact Strength of S355J2 Quality Steels Used in Power Transmission Line Construction","authors":"H. Zengin, H. Ahlatçı, Serafettin Oner, Mustafa Emre Demirkazik, S. Ozcelik, Y. Turen, Yavuz Sun","doi":"10.13189/UJMS.2018.070101","DOIUrl":"https://doi.org/10.13189/UJMS.2018.070101","url":null,"abstract":"Heat treatment is the most commonly used production step which can change the overall mechanical properties of the material without changing the chemical composition. Among the heat treatment methods, accelerated cooling has been regarded as one of the most important method for obtaining good mechanical properties. Today, this method is used in the manufacture of thin pearlitic steel, double phase steel, bainitic steel in the production process of many different quality and size products from construction bar to profile. In the scope of this study, investigations were carried out on S355J2 equal angles section profiles produced by hot rolling method. It was observed that intensive inclusions were found in all of the materials and the mechanical strength could not be met at low rolling ratios. Particularly, these materials with low impact resistance have been subjected to accelerated cooling process in order to increase their impact strength. As a result of the accelerated cooling process, significant increases in impact strength have been observed, particularly with the change of microstructure.","PeriodicalId":375998,"journal":{"name":"Universal Journal of Materials Science","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124121649","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 : 2018-11-01DOI: 10.13189/UJMS.2018.060505
Jayatin, C. Liza, Syuhada
Starch blending with linear low-density polyethylene (LLDPE) is one of the plastic packaging materials alternative used for solving the plastic waste problem that difficult to degrade. Polymeric materials will change when exposed to weather that releases heat, chemistry, and light. It can be a trigger factor in the degradation process. Xenon Arc accelerated weather simulation test is one way to find out the resistance of plastic materials to weather. This study aimed to explain the effect of xenon arc light on LLDPE-starch-clay composite. In this work accelerated photodegradation tests using Xenon Arc ATLAS Ci 3000+ were carried out on LLDPE-starch-clay composite sample films. Clay, compatibilizers, and starch with a starch content of 10 wt% and 20 wt% were used to make composites masterbatch. The composite masterbatch then extruded with LLDPE and was prepared to make a film sample using Rheomex Haake Blown film. Mechanical properties of the film samples before and after xenon arc accelerated photodegradation treatment were tested using Universal Testing Machine (UTM) Shimadzu AGS-10kNG. The composite sample made from ten wt% starch showed 55% reduction in tensile strength after 14 days of degradation while sample prepared with 20 wt% starches was brittle after seven days of exposure to xenon arc light. Fourier Transform Infra-Red (FTIR) spectrophotometer test result for composite samples made from 10 wt% and 20 wt% starch after exposure to xenon arc light show increasing the intensity at the wave number of 1722 cm-1 that corresponding to carbonyl bond this proved that degradation has occurred.
{"title":"Degradation Study of LLDPE-starch-clay Composite Film Using Xenon Arc and Characterized on Mechanical and Chemical Properties","authors":"Jayatin, C. Liza, Syuhada","doi":"10.13189/UJMS.2018.060505","DOIUrl":"https://doi.org/10.13189/UJMS.2018.060505","url":null,"abstract":"Starch blending with linear low-density polyethylene (LLDPE) is one of the plastic packaging materials alternative used for solving the plastic waste problem that difficult to degrade. Polymeric materials will change when exposed to weather that releases heat, chemistry, and light. It can be a trigger factor in the degradation process. Xenon Arc accelerated weather simulation test is one way to find out the resistance of plastic materials to weather. This study aimed to explain the effect of xenon arc light on LLDPE-starch-clay composite. In this work accelerated photodegradation tests using Xenon Arc ATLAS Ci 3000+ were carried out on LLDPE-starch-clay composite sample films. Clay, compatibilizers, and starch with a starch content of 10 wt% and 20 wt% were used to make composites masterbatch. The composite masterbatch then extruded with LLDPE and was prepared to make a film sample using Rheomex Haake Blown film. Mechanical properties of the film samples before and after xenon arc accelerated photodegradation treatment were tested using Universal Testing Machine (UTM) Shimadzu AGS-10kNG. The composite sample made from ten wt% starch showed 55% reduction in tensile strength after 14 days of degradation while sample prepared with 20 wt% starches was brittle after seven days of exposure to xenon arc light. Fourier Transform Infra-Red (FTIR) spectrophotometer test result for composite samples made from 10 wt% and 20 wt% starch after exposure to xenon arc light show increasing the intensity at the wave number of 1722 cm-1 that corresponding to carbonyl bond this proved that degradation has occurred.","PeriodicalId":375998,"journal":{"name":"Universal Journal of Materials Science","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127933737","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 : 2018-11-01DOI: 10.13189/UJMS.2018.060503
A. Klyndyuk, E. Chizhova
The (x = 0.05, 0.10, 0.15) solid solutions have been synthesized by means of solid state reactions method, their crystal structure, microstructure, electrical and dielectric properties within wide interval of temperatures and frequencies have been investigated. It is found that the titanates crystallize in an orthorhombic structure and are p-type semiconductors, which sinterability and dielectric constant increase, but grain size and thermo-EMF coefficients decrease at partial substitution of titanium by niobium and manganese. It is established that ceramics is electrically homogeneous and relaxation processes in it are non-Debye-like, and values of activation energy of relaxation obtained from results of impedance and modulus spectroscopy are in a good agreement.
{"title":"Dielectric Properties of Bi4(Ti,Nb,Mn)3O12 Titanates","authors":"A. Klyndyuk, E. Chizhova","doi":"10.13189/UJMS.2018.060503","DOIUrl":"https://doi.org/10.13189/UJMS.2018.060503","url":null,"abstract":"The (x = 0.05, 0.10, 0.15) solid solutions have been synthesized by means of solid state reactions method, their crystal structure, microstructure, electrical and dielectric properties within wide interval of temperatures and frequencies have been investigated. It is found that the titanates crystallize in an orthorhombic structure and are p-type semiconductors, which sinterability and dielectric constant increase, but grain size and thermo-EMF coefficients decrease at partial substitution of titanium by niobium and manganese. It is established that ceramics is electrically homogeneous and relaxation processes in it are non-Debye-like, and values of activation energy of relaxation obtained from results of impedance and modulus spectroscopy are in a good agreement.","PeriodicalId":375998,"journal":{"name":"Universal Journal of Materials Science","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132974888","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 : 2018-11-01DOI: 10.13189/ujms.2018.060504
Müslim Çelebi, A. Çanakçı, Serdar Özkaya, A. H. Karabacak
In this study, ZA27/Al2O3 nanocomposites reinforced with 1 vol.% Al2O3 nanoparticles were produced using mechanical milling and hot pressing method. The milling time was changed between 1h to 8h. The hot pressing prose was performed in vacuum at 432℃ and pressure of 600 MPa. The effect of milling time on the density, hardness and tensile strength of the ZA27/Al2O3 nanocomposites were investigated. The results show that the increase in milling time resulted as a decrease in the density of nanocomposite due to the change in hardness of that. It was observed that the tensile strength of the nanocomposites reached their maximum value (163 MPa) at milling time of 2h and then decreased linearly with increasing milling time. Moreover, the hardness of the nanocomposite milled for 8h was obtained as 155 HB which is about 9 % higher than the hardness of nanocomposite milled for 1h. A linearly increase was also observed the hardness of nanocomposites.
{"title":"The Effect of Milling Time on the Mechanical Properties of ZA27/Al2O3 Nanocomposites","authors":"Müslim Çelebi, A. Çanakçı, Serdar Özkaya, A. H. Karabacak","doi":"10.13189/ujms.2018.060504","DOIUrl":"https://doi.org/10.13189/ujms.2018.060504","url":null,"abstract":"In this study, ZA27/Al2O3 nanocomposites reinforced with 1 vol.% Al2O3 nanoparticles were produced using mechanical milling and hot pressing method. The milling time was changed between 1h to 8h. The hot pressing prose was performed in vacuum at 432℃ and pressure of 600 MPa. The effect of milling time on the density, hardness and tensile strength of the ZA27/Al2O3 nanocomposites were investigated. The results show that the increase in milling time resulted as a decrease in the density of nanocomposite due to the change in hardness of that. It was observed that the tensile strength of the nanocomposites reached their maximum value (163 MPa) at milling time of 2h and then decreased linearly with increasing milling time. Moreover, the hardness of the nanocomposite milled for 8h was obtained as 155 HB which is about 9 % higher than the hardness of nanocomposite milled for 1h. A linearly increase was also observed the hardness of nanocomposites.","PeriodicalId":375998,"journal":{"name":"Universal Journal of Materials Science","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116161186","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 : 2018-11-01DOI: 10.13189/UJMS.2018.060502
Tung Son Vinh Nguyen, T. M. Huynh, T. D. To, T. Doan, C. M. Dang
Silver/silver chloride (Ag/AgCl) is commonly used as a reference electrode in electrochemical measurements. However, commercial macroscopic Ag/AgCl electrodes cannot be used in micro-electrochemical sensors. Thus, many scientists are trying to miniaturize reference electrodes to integrate into one sensor chip. In this paper a new approach for fabrication of Ag/AgCl thin films coated with agarose gel as planar reference electrodes for potentiometric sensors is introduced. A silver thin film of 220-250 nm was sputtered and patterned on silicon dioxide/ silicon substrates by lithography and lift-off techniques. A AgCl layer was coated on the Ag film by using a Ag[NH3]2Cl complex at 80℃ in vacuum. The thickness of the AgCl layers was about 5um. The Ag/AgCl layers were then coated with an agarose gel. The AgCl layers were characterized by X-ray diffraction, micro Raman spectroscopy and scanning electron microscopy. The Open Circuit Potential (OCP) measurements with the fabricated electrodes as reference electrodes in pH 7 buffer solutions were performed in comparison with a commercial Ag/AgCl electrode. The potential difference between the fabricated Ag/AgCl electrodes and the commercial Ag/AgCl electrode was insignificant. The coating of the agarose layer as a protection layer of the Ag/AgCl electrodes enhanced the durability of the modified electrodes. The results indicated that the fabricated Ag/AgCl thin films coated with the agarose gel could be used as planar reference electrodes for potentiometric sensors.
{"title":"Ag/AgCl Film Electrodes Coated with Agarose Gel as Planar Reference Electrodes for Potentiometric Sensors","authors":"Tung Son Vinh Nguyen, T. M. Huynh, T. D. To, T. Doan, C. M. Dang","doi":"10.13189/UJMS.2018.060502","DOIUrl":"https://doi.org/10.13189/UJMS.2018.060502","url":null,"abstract":"Silver/silver chloride (Ag/AgCl) is commonly used as a reference electrode in electrochemical measurements. However, commercial macroscopic Ag/AgCl electrodes cannot be used in micro-electrochemical sensors. Thus, many scientists are trying to miniaturize reference electrodes to integrate into one sensor chip. In this paper a new approach for fabrication of Ag/AgCl thin films coated with agarose gel as planar reference electrodes for potentiometric sensors is introduced. A silver thin film of 220-250 nm was sputtered and patterned on silicon dioxide/ silicon substrates by lithography and lift-off techniques. A AgCl layer was coated on the Ag film by using a Ag[NH3]2Cl complex at 80℃ in vacuum. The thickness of the AgCl layers was about 5um. The Ag/AgCl layers were then coated with an agarose gel. The AgCl layers were characterized by X-ray diffraction, micro Raman spectroscopy and scanning electron microscopy. The Open Circuit Potential (OCP) measurements with the fabricated electrodes as reference electrodes in pH 7 buffer solutions were performed in comparison with a commercial Ag/AgCl electrode. The potential difference between the fabricated Ag/AgCl electrodes and the commercial Ag/AgCl electrode was insignificant. The coating of the agarose layer as a protection layer of the Ag/AgCl electrodes enhanced the durability of the modified electrodes. The results indicated that the fabricated Ag/AgCl thin films coated with the agarose gel could be used as planar reference electrodes for potentiometric sensors.","PeriodicalId":375998,"journal":{"name":"Universal Journal of Materials Science","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128201909","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 : 2018-11-01DOI: 10.13189/UJMS.2018.060501
Tuba Bahtli, V. Bostanci, Derya Yeşim Hopa, Serife Yalcin Yasti
Thermal shock resistance of MgO-C refractories, which were used in the iron and steel industry, by incorporation of pyrolytic carbon black obtained by waste tire pyrolysis was investigated. The effect of porosity on the thermal shock resistance of those refractories as a function of carbon source (graphite or pyrolytic carbon black) was also examined in the current study. The microstructure and fracture surfaces were characterized using the Scanning Electron Microscopy (SEM). Experimental studies showed that refractories produced by the use of pyrolytic carbon black had higher amount of porosity and lower thermal shock resistance than refractories containing flake graphite.
{"title":"The Effect of Carbon Sources on the Thermal Shock Properties of MgO-C Refractories","authors":"Tuba Bahtli, V. Bostanci, Derya Yeşim Hopa, Serife Yalcin Yasti","doi":"10.13189/UJMS.2018.060501","DOIUrl":"https://doi.org/10.13189/UJMS.2018.060501","url":null,"abstract":"Thermal shock resistance of MgO-C refractories, which were used in the iron and steel industry, by incorporation of pyrolytic carbon black obtained by waste tire pyrolysis was investigated. The effect of porosity on the thermal shock resistance of those refractories as a function of carbon source (graphite or pyrolytic carbon black) was also examined in the current study. The microstructure and fracture surfaces were characterized using the Scanning Electron Microscopy (SEM). Experimental studies showed that refractories produced by the use of pyrolytic carbon black had higher amount of porosity and lower thermal shock resistance than refractories containing flake graphite.","PeriodicalId":375998,"journal":{"name":"Universal Journal of Materials Science","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129546624","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 : 2018-08-01DOI: 10.13189/ujms.2018.060403
M. M. Costa, S. L. S. Melo, E. Deus
Due to environmental problems and exhaustion related to materials provided from non-renewable sources, the development of recycling technologies using residue as raw material has grown increasingly. Polypropylene (PP), a thermoplastic polymer, despite be easily recycled, presents a decrease in their mechanical properties after reprocessing cycles. In order to solve this problem, reinforcements may be added, producing a composite with better properties. The choosing of the dispersed phase aimed to consider, especially, its mechanical properties. Moreover, it was also considered the orientations of the incorporated fibers at the composite mechanical strength. In this scenario, a composite material of polymer matrix from recycled PP reinforced unidirectionally and bidirectionally with bamboo fibers were prepared. The fibers were treated with modifiers in order to increase the adhesion between polymer/fiber. The results showed that the use of reinforcement improves the mechanical properties of the polymer. Also, the superficial treatments were effective, indicating that there was an increase of the compatibility between the materials. It can be also inferred that the orientation of the fibers has directly influence at the final properties of the composite.
{"title":"Synthesis of Polymeric Composites Reinforced with Unidirectional and Bidirectional Bamboo Fibers","authors":"M. M. Costa, S. L. S. Melo, E. Deus","doi":"10.13189/ujms.2018.060403","DOIUrl":"https://doi.org/10.13189/ujms.2018.060403","url":null,"abstract":"Due to environmental problems and exhaustion related to materials provided from non-renewable sources, the development of recycling technologies using residue as raw material has grown increasingly. Polypropylene (PP), a thermoplastic polymer, despite be easily recycled, presents a decrease in their mechanical properties after reprocessing cycles. In order to solve this problem, reinforcements may be added, producing a composite with better properties. The choosing of the dispersed phase aimed to consider, especially, its mechanical properties. Moreover, it was also considered the orientations of the incorporated fibers at the composite mechanical strength. In this scenario, a composite material of polymer matrix from recycled PP reinforced unidirectionally and bidirectionally with bamboo fibers were prepared. The fibers were treated with modifiers in order to increase the adhesion between polymer/fiber. The results showed that the use of reinforcement improves the mechanical properties of the polymer. Also, the superficial treatments were effective, indicating that there was an increase of the compatibility between the materials. It can be also inferred that the orientation of the fibers has directly influence at the final properties of the composite.","PeriodicalId":375998,"journal":{"name":"Universal Journal of Materials Science","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128776280","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 : 2014-09-01DOI: 10.13189/UJMS.2014.020503
D. Vesely, M. Zhu, F. Jian
Understanding diffusion and permeability processes in organic materials is important for applications to structural components, protective coatings or packaging. In this work some basic behaviour of solvent diffusion into and through a polymer are studied using acetone and un-plasticized polyvinyl chloride at room temperature as model materials. Special cell for gravimetric measurements is used to provide data on diffusion and permeability rates through samples of different thicknesses. It is shown that the rates of mass transport are slowing down with thickness for diffusion and also for permeability, as expected. However permeability mass transport is slower than mass delivered to the outer surface by diffusion. This is explained and experimentally verified by insufficient saturation of the surface layer, as the solvent evaporates before a full saturation is reached. When the outer surface layer is pre-saturated with solvent, permeability will increase several times. When evaporation is restricted (e.g. closed cavity) the liquid solvent will accumulate, filling up the cavity. Concentration profiles, measured by infrared microscopy, confirm this observation. It is suggested that the experimental data can be explained by using chemical potential and chemical reaction kinetics.
{"title":"The Effect of Surface Conditions on Diffusion and Permeability of Acetone through uPVC","authors":"D. Vesely, M. Zhu, F. Jian","doi":"10.13189/UJMS.2014.020503","DOIUrl":"https://doi.org/10.13189/UJMS.2014.020503","url":null,"abstract":"Understanding diffusion and permeability processes in organic materials is important for applications to structural components, protective coatings or packaging. In this work some basic behaviour of solvent diffusion into and through a polymer are studied using acetone and un-plasticized polyvinyl chloride at room temperature as model materials. Special cell for gravimetric measurements is used to provide data on diffusion and permeability rates through samples of different thicknesses. It is shown that the rates of mass transport are slowing down with thickness for diffusion and also for permeability, as expected. However permeability mass transport is slower than mass delivered to the outer surface by diffusion. This is explained and experimentally verified by insufficient saturation of the surface layer, as the solvent evaporates before a full saturation is reached. When the outer surface layer is pre-saturated with solvent, permeability will increase several times. When evaporation is restricted (e.g. closed cavity) the liquid solvent will accumulate, filling up the cavity. Concentration profiles, measured by infrared microscopy, confirm this observation. It is suggested that the experimental data can be explained by using chemical potential and chemical reaction kinetics.","PeriodicalId":375998,"journal":{"name":"Universal Journal of Materials Science","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116727112","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 : 2014-04-01DOI: 10.13189/UJMS.2014.020402
V. Maslov, V. Lashkaryov
The investigations have shown the following promising tendencies in technologies for joining materials used in precision techniques: Removal of the damaged surface layer by chemical etching the joined surfaces allows, up to 6-fold enhancing both durability of part and glue conjunction between it. To modify properties of silicon-organic epoxy glue not only near the surface of combined parts but over the whole thickness of the glue joint, offered have been glue compositions based on thermo stable silicon-organic glue with embedded in it filler in the form of powder consisting of nano-dimensional (15 to 20 nm) particles of zirconium oxide in the amount up to 20 mass. %. The developed diamond-glue composition enables to shorten the duration of cooling the glue conjunction leucosapphire-copper to cryogenic temperature (from the room one down to 80 K) by 1.5 times and obtain the 6-fold increased durability, as well as higher reliability and longevity under thermal shocks. This composition is also recommended to provide efficient and uniform heat removal in solar panels. Deposition of the chromium vacuum coating with the thickness 50 to 100 nm modifies the Teflon surface and allows using the traditional glues for joining the parts processed in this way.
{"title":"Promising Micro-Nano-Technologies and Materials for Joining Precision Parts of Optics-and-Electronics Devices","authors":"V. Maslov, V. Lashkaryov","doi":"10.13189/UJMS.2014.020402","DOIUrl":"https://doi.org/10.13189/UJMS.2014.020402","url":null,"abstract":"The investigations have shown the following promising tendencies in technologies for joining materials used in precision techniques: Removal of the damaged surface layer by chemical etching the joined surfaces allows, up to 6-fold enhancing both durability of part and glue conjunction between it. To modify properties of silicon-organic epoxy glue not only near the surface of combined parts but over the whole thickness of the glue joint, offered have been glue compositions based on thermo stable silicon-organic glue with embedded in it filler in the form of powder consisting of nano-dimensional (15 to 20 nm) particles of zirconium oxide in the amount up to 20 mass. %. The developed diamond-glue composition enables to shorten the duration of cooling the glue conjunction leucosapphire-copper to cryogenic temperature (from the room one down to 80 K) by 1.5 times and obtain the 6-fold increased durability, as well as higher reliability and longevity under thermal shocks. This composition is also recommended to provide efficient and uniform heat removal in solar panels. Deposition of the chromium vacuum coating with the thickness 50 to 100 nm modifies the Teflon surface and allows using the traditional glues for joining the parts processed in this way.","PeriodicalId":375998,"journal":{"name":"Universal Journal of Materials Science","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132508800","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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