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Polymer blends of poly(lactic acid) and starch for the production of films applied in food packaging: A brief review

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Polymers from Renewable Resources 2023年第2期14卷 108-153页

作者： Carneiro da Silva, Lucas Rafael Rios, Alessandro de Oliveira Campomanes Santana, Ruth Marlene Postgraduate Program in Mining Metallurgical and Materials Engineering Laboratory of Polymeric Materials Federal University of Rio Grande do Sul Rio Grande do Sul Brazil Postgraduate Program in Food Science and Technology Laboratory of Bioactive Compounds Federal University of Rio Grande do Sul Rio Grande do Sul Brazil

The limited degradation of synthetic polymers used in food packaging when discarded in the environment is a major concern for society. Therefore, industry and academia have sought to develop biodegradable and eco-friendly materials for single-use in packaging. An interesting alternative for the food industry is biodegradable polymeric films, which is why different biopolymers have been used in the production of sustainable packaging. It is worth mentioning that the use of biodegradable polymers is one of the most successful innovations in the industry to address issues related to the environment. Among the available raw materials, starch extracted from different renewable sources is very promising for this purpose, due to its abundance, low-cost compared to other polymers and ability to produce non-toxic films. However, when used alone, pure starch has many limitations, which can be overcome by developing a mixture with other polymers (polymer blends), preferably from renewable and biodegradable sources, such as poly(lactic acid) (PLA). In this context, the absence of literature reviews evidencing the results of the application of films in foods led us to write this article, given the importance of polymer blends produced with different types of starch (cassava, corn, pea, potato, rice and wheat) and the PLA matrix. According to the results, it is clear that polymer blends based on PLA/Starch for food packaging are very promising, already being part of the industries solutions, aiming to minimize the large volume of plastic waste of petrochemical origin discarded in nature. Obviously, as with any technology, more research is needed to further improve the performance of the films, and while much research has made great strides, there are still limitations that prevent the commercialization of these materials. © The Author(s) 2023.

关键词： Starch

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Stability Analysis of Paste Fill as Stope Wall using Analytical Method and Numerical Modeling in TheKencana Underground Gold mining with Long Hole Stope Method

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Procedia Earth and Planetary Science 2013年 6卷 474-484页

作者： Razak Karim Ganda M. Simangunsong Budi Sulistianto Arnol Lopulalan Postgraduate Program Mining Engineering Institute Technology Bandung Bandung 40191 Indonesia Institute Technology Bandung Bandung 40191 Indonesia Undergraduate Program Mining Engineering Institute Technology Bandung Bandung 40191 Indonesia

The stability of the stope opening is a factor that greatly determines succesfull operation of an underground mining. In order to be a safe mining method by using paste fill, it is necessary to do a research on the stability of paste fill which is used to fi ll the mining stope. The study was conducted based on the analytical method and numerical modeling. The limit equili brium method was used to analysis the stability of paste fill considering the acting forces and mechanical strength of paste fill, for num erical modeling was used distinct element method with the program of 3DEC version 4.00 from Itasca, used to displacement analysis of paste fill that can be slided and collapsed by using the rigid and deformeable analysis. The stability analysis of paste fill was perform to ensure safety of mining activities in Kencana underground gold mine.

关键词： Stability Paste fill Factor of safety Stope Numerical modeling Displacement

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Surface analysis of different wood polymer composites exposed to artificial weathering

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Journal of Wood Chemistry and Technology 2024年第2期44卷 88-101页

作者： Andrey Pereira Acosta Sandro Campos Amico Rafael de Avila Delucis André Luiz Missio Marlon Bender Bueno Rodrigues Ana Carolina Rodrigues Ribeiro Matheus de Paula Goularte Darci Alberto Gatto a PostGraduate Program in Mining Metallurgical and Materials Engineering Federal University of Rio Grande do Sul Porto Alegre Brazil b PostGraduate Program in Materials Science and Engineering Federal University of Pelotas Pelotas Brazil c Materials Engineering Undergraduate Course Federal University of Pelotas Pelotas Brazil

This study presents a superficial analysis of different wood polymer composites (WPC) comprising polystyrene (WPSC), poly(furfuryl alcohol) (WPFAC), and pine resin (WPRC) when exposed to artificial weathering. The study investigates the influence of resin type on the composites, focusing on their chemical, colorimetric, morphological, and thermal properties. The main findings indicate WPSC exhibits poor resistance to weathering, allowing ultraviolet radiation damage on the lignocellulosic component of the composite, leading to oxidized groups formation. Conversely, WPFAC and WPRC demonstrate good wood protection capabilities by preventing significant deterioration of holocellulose and acting as filters for radiation and moisture. Moreover, WPFAC exhibits the lowest decrease in carbonyl index and O/C ratio, with reductions of 2.6 and 11.6%, respectively. These findings are significant as they demonstrate that poly(furfuryl alcohol) and pine resin can be used to produce WPCs that delay and mitigate wood degradation by weathering, contributing to the increased potential utilization of *** AbstractDisplay full size

关键词： Chemical changes discoloration surface color UV degradation

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Effects of Anodizing Parameters in Tartaric-Sulphuric Acid on Coating Thickness and Corrosion Resistance of Al 2024 T3 Alloy

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Journal of Minerals and Materials Characterization and Engineering 2015年第3期3卷 154-163页

作者： Mohammad Zaki Mubarok Wahab Sutarno Soleh Wahyudi Department of Metallurgical Engineering Faculty of Mining and Petroleum Engineering Institut Teknologi Bandung Bandung Indonesia Department of Chemistry Faculty of Mathematic and Natural Sciences Halu Oleo University Kendari Indonesia Mineral and Metallurgical Engineering Specialization Postgraduate Program of Mining Engineering Faculty of Mining and Petroleum Engineering Institut Teknologi Bandung Bandung Indonesia PT. Rekayasa Plating Cimahi Jawa Barat Indonesia

2024 T3 is one of aluminium alloys which are widely used in the aircraft structures. Anodizing of alluminium alloy in tartaric-sulphuric acid (TSA) electrolyte is developed to obtain more environmentally-friendly process and to produce anodize layer with better corrosion resistance. In this research work, the influences of anodizing parameters of Al 2024 T3 in TSA on the thickness, weight and corrosion resistance of the anodize layer are studied. Corrosion resistance test was carried out by conducting salt spray test for 336 hours and anodic polarization measurements using potentiostat. Results of three-factor analysis of variance (ANOVA) demonstrated that the most influencing factor that determines the thickness and weight of the anodize layer is temperature, followed by applied voltage, duration of anodizing, voltage-temperature interaction, interaction of temperature-duration of anodizing, interaction of voltage-temperature-duration of anodizing, and interaction of voltage and duration of anodizing. The pit density and corrosion current density (icorr) were found to be dependent on the coating thickness. The anodize layer with a thickness of higher than 3 μm was not experienced to pitting corrosion during 336 hours of salt spray test.

关键词： Aluminium Alloy Anodizing TSA Corrosion Polarisation Pitting

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Analysis of JHA and JSA at KIP 16 Bangka Ocean mining Units PT Timah (Persero) Tbk Bangka Belitung Islands Province 1

Analysis of JHA and JSA at KIP 16 Bangka Ocean Mining Units ...

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1st International Conference on Environmental Sciences, ICES 2018

作者： Rahmahwati Joni, Riri Rusli, H.A.R. Dewata, Indang Department of Environmental Science Postgraduate Program Universitas Negeri Padang Prof. Dr. Hamka Street West Air Tawar Padang-West Sumatra25131 Indonesia Department of Mining Engineering Faculty of Engineering Universitas Negeri Padang Prof. Dr. Hamka Street West Air Tawar Padang-West Sumatra25131 Indonesia

This research discusses about safety and health occupational control in Bangka Ocean KIP Timah 16 Units using some risk management methods. The methods are Job Hazard Analysis (JHA) and Job Safety Analysis (JSA). Purpose of the research is to explain safety and health occupational in KIP Timah 16 Unit it is for get the improvement of productivity work, production, welfare and comfortability workers and achievement of zero accident. The type of the research is descriptive. There are two data had collected. They are primary and secondary data. Primary data get from interview with the employees and secondary data get from K3 documents in the enter company of PT. Timah UPLB and KIP 16. Based on result of research can get some conclusions. First, to use method JHA and JSA for identification and control occupational accident. © 2019 Published under licence by IOP Publishing Ltd.

关键词： Risk management

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Development of a Methodology for Forecasting of Photovoltaic Generation in the Short and Medium Term Based on an Analysis of a Photovoltaic System and a Meteorological Forecasting Platform

SSRN

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SSRN 2024年

作者： Rosso, André Possamai Rampinelli, Giuliano Arns Schaeffer, Lirio Federal University of Rio Grande do Sul Porto Alegre Brazil Postgraduate Program in Mining Metallurgical and Materials Engineering Antônio Marcelo Ferreira Street 41 Criciúma Santa Catarina88810-016 Brazil Federal University of Santa Catarina Araranguá Brazil Postgraduate Program in Energy and Sustainability Pedro João Pereira Street 150 Araranguá Santa Catarina88905-120 Brazil Postgraduate Program in Mining Metallurgical and Materials Engineering Aneron Correa de Oliveira Street 250 Porto Alegre Rio Grande do Sul 91410-070 Brazil

Uncertainties in PV production can make it challenging to dispatch energy into the electricity grid. Although PV storage solves this problem, predicting the solar photovoltaic (PV) energy produced is necessary to control the energy injected into the grid. In Brazil, photovoltaic solar energy has grown exponentially in recent years. The current scenario in Brazil is a synergy of legal, regulatory, research and development, fiscal, tax, and economic incentives. With the country's solar energy growth, there is a need to develop and apply methodologies for predicting photovoltaic generation. This article aims to develop a methodology (RRS) for predicting photovoltaic generation in the short (1h to 10h future) and medium (24h future) terms using the generation data from a grid-connected photovoltaic system and to compare it with the persistence method (PM). Numerical weather prediction (NWP) variables such as irradiance, cloud cover, and precipitation are input for next-day prediction models. Photovoltaic predictions for the next day's horizon show the most significant errors compared to predictions for the horizon a few hours ahead. The proposed RRS model is simple, easy to access and apply, and does not use irradiance data. In the RRS model, some parameters are already built in and do not need to be dealt with, such as soiling of the photovoltaic modules, shading, spectral mismatch of the photovoltaic cells with the radiation spectrum, losses due to mismatch, losses due to cabling, losses due to series and parallel resistance, among others. The application of the RRS methodology requires two searches/inputs. The first input is weather forecast data obtained from a weather forecasting platform, and the second is actual historical data on photovoltaic generation at the site where the method was developed. © 2024, The Authors. All rights reserved.

关键词： Weather forecasting

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Tecnological Tests of the Pegamites Residues Extraction at Alto Dois Irmãos/Pb in Borborema Pegmatitic Province/Bpp

SSRN

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SSRN 2023年

作者： Silva, Gerson Ferreira de Brum, Irineu Cordeiro, Vinícius Becheleni, Emily Araújo, Defsson Federal University of Rio Grande do Sul – UFRGS Postgraduate Program in Mining Engineering Metallurgical and of Materials Brazil Federal University of Rio Grande do Sul – UFRGS Department of Metallurgical Engineering Postgraduate Program in Mining Engineering Metallurgical and Materials Brazil Federal University of Campina Grande – UFCG Academic Unity of Mining and Geology Brazil Federal University of Vales do Jequitinhonha e Mucuri – UFVJM Engineering Institute Science and Technology Brazil Federal University of Campina Grande – IFPB Federal Institute of Science Education and Technology of Paraíba Campus Picuí Brazil

The Borborema Pegmatitic Province – BPP situated between Paraiba and Rio Grande do Norte states in Brazilian northeast presents several pegmatites occurrences. In the region of the county of Pedra Lavrada – PB, are observed various mineral occurrences where the pegmatites have been explored with prominence at Alto Dois Irmãos-PB pegmatite, in what quartz, feldspar and mica are extracted. Because an existence of a complex mineralogy of the pegmatites, the understanding about mineral constituent is fundamental to define its industrial employment and also to implement improvements in beneficiation process. The proposal of this research line is the detailed characterization and proof that part of the ore (quartz) considered sterile, presents low poisoning (Fe2O3) and high silica (SiO2) content, to enable its industrial use mainly to nobler purposes. Also will be fundamental to minimize the environmental impact and decrease the grinding energetic consume. Besides that, the obtained results of this research will be used in a future work, as inputs in simulation stage, aiming to optimize the researched beneficiation unity grinding process. To the pegmatite characterization were done density determination tests, mineralogical identification by X-ray diffraction (XRD), chemical analysis by fluorescents X-rays and morphological analysis by scanning electron microscopy (SEM/EDS). Then were done tests to Work Index (WI) calculous. The sterile (quartz extraction) from pegmatite mining in Pedra Lavrada/PB presented medium density of 2,66g/cm3, majority chemical composition of silicon and oxygen and quartz as the mainly mineralogical stage, through X-ray diffractograms and scanning electron microscopy images, what indicates that this material has high purity. The Work Index (WI) was 15,9 kwh/t, showing that this material presents in the pegmatite can be consider resistant to breaking in grinding process. © 2023, The Authors. All rights reserved.

关键词： Quartz

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The assessment of claystone, quartz and coconut shell charcoal for adsorbing heavy metals ions in acid mine drainage

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IOP Conference Series: Materials Science and Engineering 2020年第1期858卷

作者： F Mukarrom Pranoto R Karsidi E Gravitiani F Astuti W Maharditya Doctorate Program of Enviromental Science Postgraduate Sebelas Maret University Mining Engineering Department Institut Teknologi Nasional Yogyakarta Yogyakarta

This research aims to determine the assessment of claystone, quartz and coconut shell charcoal for adsorbing heavy metals ions in acid mine drainage. Claystone is activated by using NaOH 3M, quartz sand is activated by using Na2CO3, while coconut shell charcoal is activated with HCl 4M. The adsorbent characterization was done by Fourier Transform Infrared Analyzer (FTIR) and X-Ray Diffraction (XRD). The results of the characterization of claystone FTIR showed the presence of active groups of silanol (Si-OH) and aluminol (Al-OH), XRD claystone characterization showed the presence of montmorillonite, kaolinite, illite and quartz minerals. While the results of FTIR characterization of quartz sand showed the presence of active groups of silanol (Si-OH) and siloxan (Si-O-Si), XRD characterization of quartz sand showed the presence of quartz mineral content. Furthermore, coconut shell charcoal showed the presence of hydroxyl (OH) and carboxyl active groups. (COOH) which is known from FTIR analysis as well as the mineral content of cristobalite, fayalite and manganoan which are known from XRD analysis. From the results of the FTIR and XRD analysis, it can be concluded that the three adsorbents have the potential as adsorbents. So that they can be used as an acid mine water absorber.

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Use of Fractals Channels to Improve a Proton Exchange Membrane Fuel Cell Performance

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Journal of Energy and Power Engineering 2015年第8期9卷 727-730页

作者： Pablo Martin Belchor Paloma Barbieri Gabriel Benetti Evandro Mathias Mayra Klein Joao Bottin Deyse Suman Carpenter Maria Madalena Camargo Forte Department of Materials School of Engineering UFRGS (Federal University of Rio Grande doSul)/PPG3M (Postgraduate Program in Mining Metallurgy and Materials) Porto Alegre 91501-970 Brazil Exact and Technological Sciences UNOESC (University of Oeste de Santa Catarina) Campus II Joagaba 89600-000 Brazil Department of Materials the FURB (Foundation Regional University of Blumenau) Campus 11 Blumenau 89030-000 Brazil

One of the most important and effective hardware elements for improvement of efficiency and power density of proton exchange membrane fuel cells is the flow field plate. The design and the pattern of the flow field plate have a considerable effect on the effectiveness of mass transport as well as on the electrochemical reactions inside the cell. The configuration of the flow field plate aims at ensuring a low pressure-drop over all channels in the stack. In this work, a FPFFP （fractal parallel flow field plate）, with bio-inspired configuration by insertion of fractals in a classic PFFP （parallel flow field plate）, is proposed, increasing the flow area of the hydrogen at anode side without increasing the section＇s area of the flow field plate. By simulating was observed that, the use of channels in fractal shape can increase the hydrogen flow area without occuring pressure loss in the cell. The fluid dynamic behavior in the FPFFP at smaller scales was replicated in the same plate, with better advantage of the active area of the electrode. Increasing the hydrogen flow area without causing pressure loss could be a good tactic to increase the power density of fuel cells, and consequently improving the cell performance.

关键词： Fuel cells flow field design fractals power simulation.

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Synthesis, Characterization, and performance test of modified Zeolite-Si/Al nanocomposite from pumice and waste cans using slow pyrolysis process for removal pollutant parameters from hard water

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Environmental Nanotechnology, Monitoring and Management 2023年 20卷

作者： Gusti Wibowo, Yudha Sudibyo Rianjanu, Aditya Taher, Tarmizi Susanti, Noni Karo Karo, Pulung Suprihatin Iman Supriyatna, Yayat Prasetyo, Erik Bahfie, Fathan Amin, Muhammad Syarifuddin, Hutwan Safitri, Hana Khairurrijal, Khairurrijal Department of Mining Engineering Institut Teknologi Sumatera Lampung-35365 Indonesia Research Center for Mining Technology National Research and Innovation Agency Lampung Indonesia Department of Material Engineering Institut Teknologi Sumatera Lampung-35365 Indonesia Department of Environmental Engineering Institut Teknologi Sumatera Lampung-35365 Indonesia Physics Department Universitas Lampung Lampung Indonesia Department of Environmental Science Postgraduate Program Universitas Jambi Jambi 36122 Indonesia Laboratory of Mine Environmental Department of Mining Engineering Institut Teknologi Sumatera Lampung-35365 Indonesia Department of Physics Institut Teknologi Sumatera Lampung-36365 Indonesia Department of Physics Institut Teknologi Bandung Bandung 40132 Indonesia Center for Green and Sustainable Materials Institut Teknologi Sumatera Indonesia

Hard water is one of crucial problems in the world due to its pollutant parameters. Adsorption is a promising method for treating hard water because of its benefits such as low-cost, easy to use, acceptable, and easy to maintenance. In this study, we utilized zeolite functionalized with silicon/aluminum (Ze-Si/Al) as adsorbent materials for hard water treatment. Ten different ratios of Si/Al were added into zeolite by modifying the solid waste source concentration (pumice and cans). The optimum sample was then further tested with different parameters including contact time, dye concentration, and isotherm models. The zeolite-Si/Al adsorbent was characterized by Scanning Electron Microscope (SEM), X-Ray Diffraction (XRD), and X-Ray Fluorescence (XRF). Results of this study have showed that the best functionalized zeolite was that with Si/Al ratio 0.67, which has higher sorption ability. In contact time test, the equilibrium was reached after 300 min. This study also informed that the concentration of dyes will give impact on removal of pollutant parameters. Isotherm model of Ze-Si/Al fitted with Langmuir method. This study also discussed the potential development and future research direction. Thus, this study is a crucial report to develop the information about waste utilization as source of Si/Al to increasing quality of zeolite. © 2023 Elsevier B.V.

关键词： Adsorption Hard water Wastewater Wastewater treatment zeolite-Si/Al

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