In this paper, a study was made regarding the quality of the soil, from a disused area, where there was a garbage dump, which operated illegally. Soil samples were taken from different depths, namely 10, 20, and 30 cm deep, from 3 areas, covering the entire area where was the landfill. In the soil samples taken, the proportion of heavy metals and the pH were determined, thus being able to highlight how the quality of the soil was affected.
{"title":"Studies and Research on Soil Analysis in a Derelict Area, where there Was a Landfill","authors":"B. Tudor","doi":"10.35219/mms.2023.1.07","DOIUrl":"https://doi.org/10.35219/mms.2023.1.07","url":null,"abstract":"In this paper, a study was made regarding the quality of the soil, from a disused area, where there was a garbage dump, which operated illegally. Soil samples were taken from different depths, namely 10, 20, and 30 cm deep, from 3 areas, covering the entire area where was the landfill. In the soil samples taken, the proportion of heavy metals and the pH were determined, thus being able to highlight how the quality of the soil was affected. \u0000","PeriodicalId":22358,"journal":{"name":"The Annals of “Dunarea de Jos” University of Galati. Fascicle IX, Metallurgy and Materials Science","volume":"788 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78858622","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 main theme of this work is the sustainability of buildings and their relevance for sustainable development in Romania and Europe in the current context of orientation towards sustainable augmentation, minimizing the negative impact on the environment.A sustainable building must be designed to use the necessary resources: energy, water, and materials in a more efficient way while aiming at reducing the impact that the construction itself has on the health of the occupants but also on the environment.As it is known, human activity in the last few centuries has led to the consumption of resources and the spread of pollutants in the environment. According to statistics, over time it has been proven that the construction sector is one of the most active contemporary polluters. The largest amount of greenhouse gas emissions from the building sector results from the use of energy (e.g., for heating, lighting, etc.). Thus, it is demonstrated the need to decrease energy consumption for the use of buildings, but also for their construction and recycling.
{"title":"Sustainability in Construction","authors":"Simona Stanca","doi":"10.35219/mms.2023.1.02","DOIUrl":"https://doi.org/10.35219/mms.2023.1.02","url":null,"abstract":"The main theme of this work is the sustainability of buildings and their relevance for sustainable development in Romania and Europe in the current context of orientation towards sustainable augmentation, minimizing the negative impact on the environment.A sustainable building must be designed to use the necessary resources: energy, water, and materials in a more efficient way while aiming at reducing the impact that the construction itself has on the health of the occupants but also on the environment.As it is known, human activity in the last few centuries has led to the consumption of resources and the spread of pollutants in the environment. According to statistics, over time it has been proven that the construction sector is one of the most active contemporary polluters. The largest amount of greenhouse gas emissions from the building sector results from the use of energy (e.g., for heating, lighting, etc.). Thus, it is demonstrated the need to decrease energy consumption for the use of buildings, but also for their construction and recycling.","PeriodicalId":22358,"journal":{"name":"The Annals of “Dunarea de Jos” University of Galati. Fascicle IX, Metallurgy and Materials Science","volume":"3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73911113","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}
Recent earthquakes have confirmed that non-structural walls interacting mainly with frame structures are severely damaged during seismic actions endangering human lives. The ongoing life after earthquakes and major costs for rebuilding are deeply affected. In order to avoid this kind of drawbacks, the present paper suggests the introduction of a set of joints between the structure and the nonstructural closing and division walls. The joints should observe the following: joints will be designed to provide free development of displacements in the plane of the walls with no major interactions in the structure; joints will be designed to provide transmission of the seismic forces acting perpendicularly to the non-structural walls towards the main structure. This paper will include several conclusions concerning the admission, constraint or removal of interactions between the structure and the closing and division walls.
{"title":"Fixings that Ensure the Free Movement of the Structure for Resistance in Relation to Non-Structural Walls","authors":"R. Iernuțan, L. Plesa","doi":"10.35219/mms.2023.1.01","DOIUrl":"https://doi.org/10.35219/mms.2023.1.01","url":null,"abstract":"Recent earthquakes have confirmed that non-structural walls interacting mainly with frame structures are severely damaged during seismic actions endangering human lives. The ongoing life after earthquakes and major costs for rebuilding are deeply affected. In order to avoid this kind of drawbacks, the present paper suggests the introduction of a set of joints between the structure and the nonstructural closing and division walls. The joints should observe the following: joints will be designed to provide free development of displacements in the plane of the walls with no major interactions in the structure; joints will be designed to provide transmission of the seismic forces acting perpendicularly to the non-structural walls towards the main structure. This paper will include several conclusions concerning the admission, constraint or removal of interactions between the structure and the closing and division walls. \u0000","PeriodicalId":22358,"journal":{"name":"The Annals of “Dunarea de Jos” University of Galati. Fascicle IX, Metallurgy and Materials Science","volume":"11 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90658184","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}
This article presents a study on how to prototype a finger joint exoprosthesis using different CAD software and 3D printing techniques. The article describes the measurement of morpho-anatomical parameters, the creation of a 3D model based on these parameters, and the integration of an articulation mechanism into the patient's finger. This study also outlines the process of producing the custom prosthesis prototype by using PA11 CF material, which has applications in various fields including medicine. The prosthesis was then introduced to Sinterit Studio where a G-code was generated and the layers that would be printed were visualized. This method provides insight into the process of creating a prototype using 3D printing technology and specific software applications.
{"title":"Custom Prosthetic Finger Device Using 3D Printable PA11 CF Powder","authors":"Gean-Carlos Nicholas Dumitrescu, P. Braileanu","doi":"10.35219/mms.2023.1.05","DOIUrl":"https://doi.org/10.35219/mms.2023.1.05","url":null,"abstract":"This article presents a study on how to prototype a finger joint exoprosthesis using different CAD software and 3D printing techniques. The article describes the measurement of morpho-anatomical parameters, the creation of a 3D model based on these parameters, and the integration of an articulation mechanism into the patient's finger. This study also outlines the process of producing the custom prosthesis prototype by using PA11 CF material, which has applications in various fields including medicine. The prosthesis was then introduced to Sinterit Studio where a G-code was generated and the layers that would be printed were visualized. This method provides insight into the process of creating a prototype using 3D printing technology and specific software applications. \u0000","PeriodicalId":22358,"journal":{"name":"The Annals of “Dunarea de Jos” University of Galati. Fascicle IX, Metallurgy and Materials Science","volume":"66 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87029114","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}
Topological optimization is a type of structural optimization that provides conceptual design for lighter structures. The aim of this method is to maximize system performance for a given set of loads, boundary conditions, and constraints. This method is based on element analysis finished assembly. The design of a lightweight robot is a key point since the weight of the robot is directly proportional to the load capacity of the robot and its motor power. The structural design is iterated in a loop until function convergence achieves the objectives and the atisfying constraints.
{"title":"Topological Optimization Using Neuronal Algorithm","authors":"Gabriel Procopenco, F. Marin, M. Marin","doi":"10.35219/mms.2023.1.06","DOIUrl":"https://doi.org/10.35219/mms.2023.1.06","url":null,"abstract":"Topological optimization is a type of structural optimization that provides conceptual design for lighter structures. The aim of this method is to maximize system performance for a given set of loads, boundary conditions, and constraints. This method is based on element analysis finished assembly. The design of a lightweight robot is a key point since the weight of the robot is directly proportional to the load capacity of the robot and its motor power. The structural design is iterated in a loop until function convergence achieves the objectives and the atisfying constraints. \u0000","PeriodicalId":22358,"journal":{"name":"The Annals of “Dunarea de Jos” University of Galati. Fascicle IX, Metallurgy and Materials Science","volume":"31 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87547149","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 benefits of using mathematical modeling of the flow are obvious, the final objective being the elimination of as many inclusions as possible during the flow of steel through the tundish, and thus, obtaining steel with superior quality.In this work, a simulation of the movement of the liquid alloy in the tundish was carried out, in order to highlight the erosion of its refractory lining. For this, we used SolidWorks, RealFlow, and ABAQUS programs.Using these simulation programs, the filling method of the tundish, the contact area of the alloy jet with the tundish wall, and the "dead" areas are highlighted, as well as the turbulences that can appear during the flow, which have a negative impact on the quality of the steel.
{"title":"Importance of Simulating the Steel Flow Process in the Tundish, on the Quality of Continuously Cast Slabs","authors":"B. Tudor, Al Matrood","doi":"10.35219/mms.2023.1.03","DOIUrl":"https://doi.org/10.35219/mms.2023.1.03","url":null,"abstract":"The benefits of using mathematical modeling of the flow are obvious, the final objective being the elimination of as many inclusions as possible during the flow of steel through the tundish, and thus, obtaining steel with superior quality.In this work, a simulation of the movement of the liquid alloy in the tundish was carried out, in order to highlight the erosion of its refractory lining. For this, we used SolidWorks, RealFlow, and ABAQUS programs.Using these simulation programs, the filling method of the tundish, the contact area of the alloy jet with the tundish wall, and the \"dead\" areas are highlighted, as well as the turbulences that can appear during the flow, which have a negative impact on the quality of the steel. \u0000","PeriodicalId":22358,"journal":{"name":"The Annals of “Dunarea de Jos” University of Galati. Fascicle IX, Metallurgy and Materials Science","volume":"160 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2023-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77556705","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 subject of this research was to study the effect of sintering time on the dimensional characteristics of some powder metallurgy (PM) materials. The powders used in this study are prealloyed iron-based powders with Cu, Ni and Mo. The powders were single pressed at 600 MPa and the disc specimens have the dimensions of 8-6 mm. The green compacts were sintering in a laboratory furnace at 1150 ºC for 60, 75 and 90 minutes and air-cooled to room temperature. The density of green and sintered specimens, the porosity and the dimensional changes were evaluated.
{"title":"The Investigation on Dimensional Stability in Some Sintered Powder Metallurgy Alloys","authors":"M. Marin, F. Marin","doi":"10.35219/mms.2022.4.17","DOIUrl":"https://doi.org/10.35219/mms.2022.4.17","url":null,"abstract":"The subject of this research was to study the effect of sintering time on the dimensional characteristics of some powder metallurgy (PM) materials. The powders used in this study are prealloyed iron-based powders with Cu, Ni and Mo. The powders were single pressed at 600 MPa and the disc specimens have the dimensions of 8-6 mm. The green compacts were sintering in a laboratory furnace at 1150 ºC for 60, 75 and 90 minutes and air-cooled to room temperature. The density of green and sintered specimens, the porosity and the dimensional changes were evaluated.\u0000","PeriodicalId":22358,"journal":{"name":"The Annals of “Dunarea de Jos” University of Galati. Fascicle IX, Metallurgy and Materials Science","volume":"47 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86570927","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 paper presents the results of the research carried out on an Al alloy from the 7000 series. The material was subjected to several variants of thermal and thermomechanical processing. Research has been conducted on various artificial aging temperatures of the material in combination with various aging time values. Some samples were also subjected to plastic deformation, between quenching and artificial aging, in order to determine the influence of this deformation on the values of the final mechanical properties.
{"title":"Research on the Improvement of the Mechanical Properties of Aluminum Alloys of the Series Al-Zn-Mg-Cu by Heat Processing","authors":"M. Neacsu","doi":"10.35219/mms.2022.4.06","DOIUrl":"https://doi.org/10.35219/mms.2022.4.06","url":null,"abstract":"The paper presents the results of the research carried out on an Al alloy from the 7000 series. The material was subjected to several variants of thermal and thermomechanical processing. Research has been conducted on various artificial aging temperatures of the material in combination with various aging time values. Some samples were also subjected to plastic deformation, between quenching and artificial aging, in order to determine the influence of this deformation on the values of the final mechanical properties. \u0000","PeriodicalId":22358,"journal":{"name":"The Annals of “Dunarea de Jos” University of Galati. Fascicle IX, Metallurgy and Materials Science","volume":"14 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85241361","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}
Thin polymeric films with dielectric properties become a very important part of today’s devices, being indispensable in industry, electrical applications and not only. Nowadays polymeric materials have attracted attention in academic and industrial research due to the miniaturization at the micro and nanoscale of different electronic devices. Polymers in general are used for their light weight, good mechanical strength, dielectric properties, and optical properties, which make them multifunctional materials.This paper presents research on polymethyl methacrylate (PMMA) thin films obtained by the sol-gel method. The optimization of thin film PMMA layers has been a problem due to the importance of using the polymer in the different electronic domains. Thin films of PMMA with different thicknesses were deposited onto glass and silicon wafers in order to measure dielectric properties. For dielectric properties, the PMMA thin layer was inserted in a metal-insulator-metal structure (MIM). In order to observe the morphology and roughness of thin film, optical microscopy, scanning electron microscopy and atomic force microscopy have proceeded.The dielectric constant (k) was calculated using the electrical capacitance formula. The I-V and C-V curves showed a dielectric behavior with a leakage current between 10-11 and 10-8 A and a constant capacitance in the bias range ± 5 V.
{"title":"Dielectric PMMA Thin Layers Obtained by Spin Coating for Electronic Applications","authors":"E. Herbei","doi":"10.35219/mms.2022.4.14","DOIUrl":"https://doi.org/10.35219/mms.2022.4.14","url":null,"abstract":"Thin polymeric films with dielectric properties become a very important part of today’s devices, being indispensable in industry, electrical applications and not only. Nowadays polymeric materials have attracted attention in academic and industrial research due to the miniaturization at the micro and nanoscale of different electronic devices. Polymers in general are used for their light weight, good mechanical strength, dielectric properties, and optical properties, which make them multifunctional materials.This paper presents research on polymethyl methacrylate (PMMA) thin films obtained by the sol-gel method. The optimization of thin film PMMA layers has been a problem due to the importance of using the polymer in the different electronic domains. Thin films of PMMA with different thicknesses were deposited onto glass and silicon wafers in order to measure dielectric properties. For dielectric properties, the PMMA thin layer was inserted in a metal-insulator-metal structure (MIM). In order to observe the morphology and roughness of thin film, optical microscopy, scanning electron microscopy and atomic force microscopy have proceeded.The dielectric constant (k) was calculated using the electrical capacitance formula. The I-V and C-V curves showed a dielectric behavior with a leakage current between 10-11 and 10-8 A and a constant capacitance in the bias range ± 5 V.\u0000","PeriodicalId":22358,"journal":{"name":"The Annals of “Dunarea de Jos” University of Galati. Fascicle IX, Metallurgy and Materials Science","volume":"84 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80844901","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}
Sintered copper-tin alloys are used to obtain products with numerous applications. Some bronze parts such as filters or bushings for self-lubricating bearings can only be produced by specific powder metallurgy technologies. Metal filters represent an important fraction in the field of sintered products. In the paper, measurements of the intergranular bridges were made on the samples obtained by sintering the spheroidal powder from the CuSn12 alloy. Free casting in graphite moulds followed by sintering was used (9 experiments, 3 temperatures x 3 durations). With these data, the coefficients from the Kuczinski equation were determined. Thus, the correlation between the desired porosity for a filter-type product (expressed by the size of the intergranular bridge) and the sintering technological parameters can be established.
{"title":"Experimental Determination of the Kuczynski Equation for the Case of CuSn12 Alloy Sintering","authors":"P. Alexandru, Cristian Stefănescu","doi":"10.35219/mms.2022.4.13","DOIUrl":"https://doi.org/10.35219/mms.2022.4.13","url":null,"abstract":"Sintered copper-tin alloys are used to obtain products with numerous applications. Some bronze parts such as filters or bushings for self-lubricating bearings can only be produced by specific powder metallurgy technologies. Metal filters represent an important fraction in the field of sintered products. In the paper, measurements of the intergranular bridges were made on the samples obtained by sintering the spheroidal powder from the CuSn12 alloy. Free casting in graphite moulds followed by sintering was used (9 experiments, 3 temperatures x 3 durations). With these data, the coefficients from the Kuczinski equation were determined. Thus, the correlation between the desired porosity for a filter-type product (expressed by the size of the intergranular bridge) and the sintering technological parameters can be established.\u0000","PeriodicalId":22358,"journal":{"name":"The Annals of “Dunarea de Jos” University of Galati. Fascicle IX, Metallurgy and Materials Science","volume":"11 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88749570","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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