During the casting process, the crust of the steel wire is permanently subjected to thermo mechanical stresses (temperature variations, pulling, bending and straightening forces, ferrostatic pressure), which, when exceeding the deformation capacity of the crust, can lead to cracks.Therefore, it is necessary to know what kind of stresses act on the crust and how the steel behaves at high temperatures at certain process parameters (extraction speed, cooling intensity, etc.).
{"title":"Experiments Regarding Thermal and Mechanical Deformations of Continuous Cast Steel Wire","authors":"M. Bordei, B. Carp, Dunărea de Jos","doi":"10.35219/mms.2020.2.03","DOIUrl":"https://doi.org/10.35219/mms.2020.2.03","url":null,"abstract":"During the casting process, the crust of the steel wire is permanently subjected to thermo mechanical stresses (temperature variations, pulling, bending and straightening forces, ferrostatic pressure), which, when exceeding the deformation capacity of the crust, can lead to cracks.Therefore, it is necessary to know what kind of stresses act on the crust and how the steel behaves at high temperatures at certain process parameters (extraction speed, cooling intensity, etc.).","PeriodicalId":22358,"journal":{"name":"The Annals of “Dunarea de Jos” University of Galati. Fascicle IX, Metallurgy and Materials Science","volume":"62 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86116342","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 purpose of the present work is to present results from a measuring campaign during February-March 2020, in Galati city, Romania, aiming the concentration of fine particulate matter (PM2.5) in air and their heavy metal concentrations, then comparing the results with the air quality determined by the national monitoring system from the same city. Results show considerable differences concerning the air quality measured in this study compared with measurements of the national monitoring system that consist in four stations placed across the city. While values recorded in this study exceeded, in some situations, the maximum target from PM2.5, the reports from the national monitoring system presented a good air quality, using a colour- and number-coding (maximum level 4 out of 6 was reported). Heavy metal concentrations of the fine particulate matters collected in this study was compared with other studies across the world, high Fe and Zn values being registered in agglomerated and industrialized cities, including the city considered in the present study, while in a study conducted in Beijing, China most higher values between all analysed heavy metals were recorded.
{"title":"Indoor Concentration and Composition of Fine Particulate Matter (PM2.5) Near an Intense Circulated Road in an Industrial City","authors":"M. Bodor","doi":"10.35219/mms.2020.2.01","DOIUrl":"https://doi.org/10.35219/mms.2020.2.01","url":null,"abstract":"The purpose of the present work is to present results from a measuring campaign during February-March 2020, in Galati city, Romania, aiming the concentration of fine particulate matter (PM2.5) in air and their heavy metal concentrations, then comparing the results with the air quality determined by the national monitoring system from the same city. Results show considerable differences concerning the air quality measured in this study compared with measurements of the national monitoring system that consist in four stations placed across the city. While values recorded in this study exceeded, in some situations, the maximum target from PM2.5, the reports from the national monitoring system presented a good air quality, using a colour- and number-coding (maximum level 4 out of 6 was reported). Heavy metal concentrations of the fine particulate matters collected in this study was compared with other studies across the world, high Fe and Zn values being registered in agglomerated and industrialized cities, including the city considered in the present study, while in a study conducted in Beijing, China most higher values between all analysed heavy metals were recorded.","PeriodicalId":22358,"journal":{"name":"The Annals of “Dunarea de Jos” University of Galati. Fascicle IX, Metallurgy and Materials Science","volume":"62 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85634943","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}
Titanium alloys such as Ti6Al4V is the most used alloy used as implant for biomedical purposes. The conditions for a biomaterial to be selected for a particular application in the human body is that this should to conforms to the physical, chemical and biological characteristics, more precisely to be biocompatible, biofunctional and not ultimately sterilizable. Ti6Al4V alloy has mechanical properties suitable for many biomedical applications and has excellent corrosion resistance, which depends on the presence of a stable passive oxide film forming on its surface. Our study aims to evaluate the corrosion resistance of Ti6Al4V as a function in time with addition of 5 g/L and 10 g/L Lactic acid in biological solution Hank after exposure at 0 h (at immersion time), after 48 h (from immersion) and 168 h (from immersion). The evaluation of corrosion resistance of Ti6Al4V in Hank biological solution with addition of two concentration of Lactic acid it was done by electrochemical methods in terms of open circuit potential and polarization resistance (Rp). Lactic acid is used in this study because it is a component present in human blood in small quantities and is necessary for the metabolic processes used directly by the heart muscle, brain and nervous system. The increased lactic acid content in muscle appears as weight-bearing exercises. This is why it is important to know how the presence of lactic acid in larger quantities affects the implants. The study also highlights the importance of using longer testing times and more realistic solutions when testing biomedical materials.
{"title":"Evaluation of Corrosion Resistance of Implant-use Ti6Al4V Alloy in Hank Biological Solution in the Presence of Microorganism's Metabolic Product Lactic Acid","authors":"L. Benea, N. Simionescu, Dunărea de Jos","doi":"10.35219/mms.2020.1.04","DOIUrl":"https://doi.org/10.35219/mms.2020.1.04","url":null,"abstract":"Titanium alloys such as Ti6Al4V is the most used alloy used as implant for biomedical purposes. The conditions for a biomaterial to be selected for a particular application in the human body is that this should to conforms to the physical, chemical and biological characteristics, more precisely to be biocompatible, biofunctional and not ultimately sterilizable. Ti6Al4V alloy has mechanical properties suitable for many biomedical applications and has excellent corrosion resistance, which depends on the presence of a stable passive oxide film forming on its surface. Our study aims to evaluate the corrosion resistance of Ti6Al4V as a function in time with addition of 5 g/L and 10 g/L Lactic acid in biological solution Hank after exposure at 0 h (at immersion time), after 48 h (from immersion) and 168 h (from immersion). The evaluation of corrosion resistance of Ti6Al4V in Hank biological solution with addition of two concentration of Lactic acid it was done by electrochemical methods in terms of open circuit potential and polarization resistance (Rp). Lactic acid is used in this study because it is a component present in human blood in small quantities and is necessary for the metabolic processes used directly by the heart muscle, brain and nervous system. The increased lactic acid content in muscle appears as weight-bearing exercises. This is why it is important to know how the presence of lactic acid in larger quantities affects the implants. The study also highlights the importance of using longer testing times and more realistic solutions when testing biomedical materials.","PeriodicalId":22358,"journal":{"name":"The Annals of “Dunarea de Jos” University of Galati. Fascicle IX, Metallurgy and Materials Science","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84252054","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}
At the moment, project management is a field in development and increasingly used in all economic sectors. Thus, we can specify that the project management plays a major role in order to consolidate a competitive advantage and achieve the organizational performance. In order to achieve long-term goals, it is necessary for the projects to consider several aspects, among which the mode and context of their implementation and the identification of the answers to the needs of the companies and organizations that implement the projects, as well as the follow-up of the measures / recommendations for solving certain problems. Further, in this article we will present the involvement of the project management, as well as funding sources in the field of climate change that may have major implications for agriculture.
{"title":"Project Management Implications on Climate Change","authors":"Bianca Georgiana Olaru","doi":"10.35219/mms.2020.1.07","DOIUrl":"https://doi.org/10.35219/mms.2020.1.07","url":null,"abstract":"At the moment, project management is a field in development and increasingly used in all economic sectors. Thus, we can specify that the project management plays a major role in order to consolidate a competitive advantage and achieve the organizational performance. In order to achieve long-term goals, it is necessary for the projects to consider several aspects, among which the mode and context of their implementation and the identification of the answers to the needs of the companies and organizations that implement the projects, as well as the follow-up of the measures / recommendations for solving certain problems. Further, in this article we will present the involvement of the project management, as well as funding sources in the field of climate change that may have major implications for agriculture.","PeriodicalId":22358,"journal":{"name":"The Annals of “Dunarea de Jos” University of Galati. Fascicle IX, Metallurgy and Materials Science","volume":"85 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76728908","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}
Although it appeared in Romania 50 years ago, archaeometallurgy is still treated as a new discipline, despite the fact that it was understood from the beginning that this science, by its methods and by the correct interpretation of the results obtained as a result of modern techniques of characterization of materials generally leads to the obtaining of data that are particularly important for understanding the past. The present study aims to investigate the evolution and the stage in which this field is in terms of modern techniques of characterization of the materials applied to the military equipment of the classical Geto-Dacian period.
{"title":"Archaeometallurgy and its Importance in the Research of the Preroman Dacia Military Equipment in the 1st B.C.-1st A.C. Centuries","authors":"Ovidiu Vasile Udrescu","doi":"10.35219/mms.2020.1.01","DOIUrl":"https://doi.org/10.35219/mms.2020.1.01","url":null,"abstract":"Although it appeared in Romania 50 years ago, archaeometallurgy is still treated as a new discipline, despite the fact that it was understood from the beginning that this science, by its methods and by the correct interpretation of the results obtained as a result of modern techniques of characterization of materials generally leads to the obtaining of data that are particularly important for understanding the past. The present study aims to investigate the evolution and the stage in which this field is in terms of modern techniques of characterization of the materials applied to the military equipment of the classical Geto-Dacian period.","PeriodicalId":22358,"journal":{"name":"The Annals of “Dunarea de Jos” University of Galati. Fascicle IX, Metallurgy and Materials Science","volume":"116 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77246495","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}
Within the present work deformability of Ni-P coatings was analyzed on thin strips of low carbon steel, coated with Ni-P layers in correlation with their structure and chemical composition. Thin layers of 2-7 μm were made at immersion times of 5, 10 and 15 minutes and a variable pH of between 4 and 6, at a temperature of 80-85 °C. The deformability was analyzed by applying the Erichsen Test, which measures the deep deformation capacity of the metallic materials. Following the analysis was established the Erichsen Index (IE) the most used index for assessing the deformation capacity of the sheets. The microscopic analysis, performed on the surface of maximum deformation, shows a cracking of the layers with a different aspect depending on pH, the duration of deposition and the initial structure of the layer. The results of the Errichsen test show a good behavior at plastic deformation of the strips covered with thin Ni-P layers.
{"title":"Behavior on Plastic Deformation of Thin Steel Strips Coated with Electroless Ni-P","authors":"T. Radu, F. Potecașu, Dunărea de Jos","doi":"10.35219/mms.2020.1.06","DOIUrl":"https://doi.org/10.35219/mms.2020.1.06","url":null,"abstract":"Within the present work deformability of Ni-P coatings was analyzed on thin strips of low carbon steel, coated with Ni-P layers in correlation with their structure and chemical composition. Thin layers of 2-7 μm were made at immersion times of 5, 10 and 15 minutes and a variable pH of between 4 and 6, at a temperature of 80-85 °C. The deformability was analyzed by applying the Erichsen Test, which measures the deep deformation capacity of the metallic materials. Following the analysis was established the Erichsen Index (IE) the most used index for assessing the deformation capacity of the sheets. The microscopic analysis, performed on the surface of maximum deformation, shows a cracking of the layers with a different aspect depending on pH, the duration of deposition and the initial structure of the layer. The results of the Errichsen test show a good behavior at plastic deformation of the strips covered with thin Ni-P layers.","PeriodicalId":22358,"journal":{"name":"The Annals of “Dunarea de Jos” University of Galati. Fascicle IX, Metallurgy and Materials Science","volume":"106 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88004131","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}
Material particles represent a category of air pollutants, which greatly affect human health, and include in their composition, nitrates, sulphates, organic carbon dust and salt. The paper presents determinations of the air quality, from different sectors, of a metal casting workshop. The determinations were made during the technological process of production, as well as during when the workshop does not have a production activity. In all cases, was monitored the variation of material particles (PM) concentrations. The measurements were made with the help of the particle counter, Fluke 985, the results obtained, being compared with the legislation in force, regarding safety and health at work.
{"title":"Determination of Air Quality, Through the Cumulative Measurement of the Concentration of the Material Particles, in a Workshop for Making Metal Cast Parts","authors":"B. Tudor, V. Drăgan, Dunărea de Jos","doi":"10.35219/mms.2020.1.05","DOIUrl":"https://doi.org/10.35219/mms.2020.1.05","url":null,"abstract":"Material particles represent a category of air pollutants, which greatly affect human health, and include in their composition, nitrates, sulphates, organic carbon dust and salt. The paper presents determinations of the air quality, from different sectors, of a metal casting workshop. The determinations were made during the technological process of production, as well as during when the workshop does not have a production activity. In all cases, was monitored the variation of material particles (PM) concentrations. The measurements were made with the help of the particle counter, Fluke 985, the results obtained, being compared with the legislation in force, regarding safety and health at work.","PeriodicalId":22358,"journal":{"name":"The Annals of “Dunarea de Jos” University of Galati. Fascicle IX, Metallurgy and Materials Science","volume":"248 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75025713","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}
Reducing the size of macroscopic systems to nanometers can be achieved by top down synthesis by different chemical or physical methods. The bottom-up approach is a method in which the components of the atomic or molecular dimensions are assembled together to form nanoparticles. The bottom-up method is used for the elaboration of nanoparticles, because it allows the control of their size. This article presents a review of the advantages and disadvantages of chemical methods for the development of nanomaterials
{"title":"Advantages and Disadvantages of Chemical Methods in the Elaboration of Nanomaterials","authors":"E. M. Modan, A. Plăiașu","doi":"10.35219/mms.2020.1.08","DOIUrl":"https://doi.org/10.35219/mms.2020.1.08","url":null,"abstract":"Reducing the size of macroscopic systems to nanometers can be achieved by top down synthesis by different chemical or physical methods. The bottom-up approach is a method in which the components of the atomic or molecular dimensions are assembled together to form nanoparticles. The bottom-up method is used for the elaboration of nanoparticles, because it allows the control of their size. This article presents a review of the advantages and disadvantages of chemical methods for the development of nanomaterials","PeriodicalId":22358,"journal":{"name":"The Annals of “Dunarea de Jos” University of Galati. Fascicle IX, Metallurgy and Materials Science","volume":"56 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76691312","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}
A. Leopa, A. Serban, M. Burtea, Petru Gojan, Dunărea de Jos
{"title":"Study on the Sludge Capitalization as a Fertilizer for Ornamental Garden Plants","authors":"A. Leopa, A. Serban, M. Burtea, Petru Gojan, Dunărea de Jos","doi":"10.35219/mms.2019.3.03","DOIUrl":"https://doi.org/10.35219/mms.2019.3.03","url":null,"abstract":"","PeriodicalId":22358,"journal":{"name":"The Annals of “Dunarea de Jos” University of Galati. Fascicle IX, Metallurgy and Materials Science","volume":"53 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84787856","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}
Water treatment in the magnetic field is not an officially recognized method of water softening. This method can be promoted as an alternative to water softening without potentially toxic chemical agents. The water softener device consisting of 3 pairs of permanent magnets made of neodymium was designed with the help of Solid Edge software. Numerical simulation was performed using ANSYS WORKBENCH finite element analysis software using the FluidFlow (CFX) module. With this analysis module the dynamic analysis of the fluid flow through a pipe was performed. Three numerical analyses of the water flow through a pipe with an internal diameter of 20 mm were performed at a pressure of 2 bars, namely: • the water flow without magnetic influences; • the water flow under the magnetic influence of the softener device positioned longitudinally with the pipe; • the water flow under the magnetic influence of the softener device positioned transversely with the pipe. The conclusions of these simulations can be the basis for future research in order to optimize this type of device.
{"title":"3D Modeling and Numerical Simulation of a Water Softener Device","authors":"Dorin Eftimie, Dunărea de Jos","doi":"10.35219/mms.2019.3.07","DOIUrl":"https://doi.org/10.35219/mms.2019.3.07","url":null,"abstract":"Water treatment in the magnetic field is not an officially recognized method of water softening. This method can be promoted as an alternative to water softening without potentially toxic chemical agents. The water softener device consisting of 3 pairs of permanent magnets made of neodymium was designed with the help of Solid Edge software. Numerical simulation was performed using ANSYS WORKBENCH finite element analysis software using the FluidFlow (CFX) module. With this analysis module the dynamic analysis of the fluid flow through a pipe was performed. Three numerical analyses of the water flow through a pipe with an internal diameter of 20 mm were performed at a pressure of 2 bars, namely: • the water flow without magnetic influences; • the water flow under the magnetic influence of the softener device positioned longitudinally with the pipe; • the water flow under the magnetic influence of the softener device positioned transversely with the pipe. The conclusions of these simulations can be the basis for future research in order to optimize this type of device.","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":"2019-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86866546","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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