Journal articles on the topic 'Synthetic products Recycling'
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1
Wojnowska-Baryła, Irena, Katarzyna Bernat, and Magdalena Zaborowska. "Strategies of Recovery and Organic Recycling Used in Textile Waste Management." International Journal of Environmental Research and Public Health 19, no. 10 (May 11, 2022): 5859. http://dx.doi.org/10.3390/ijerph19105859.
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Post-consumer bio-based textile wastes are any type of garment or household article made from manufactured bio-based textiles that the owner no longer needs and decides to discard. According to the hierarchy of waste management, post-consumer textile waste should be organically recycled. However, there is still a problem with the implementation of selective collection of textile waste followed by sorting, which would prepare the waste for organic recycling. A technically achievable strategy for sorted textile waste materials consisting of only one type of fiber material, multi-material textiles are a problem for recycling purposes. Waste textiles are composed of different materials, including natural as well as synthetic non-cellulosic fibers, making bioprocessing difficult. Various strategies for recovery of valuable polymers or monomers from textile waste, including concentrated and dilute acid hydrolysis, ionic liquids as well as enzymatic hydrolysis, have been discussed. One possible process for fiber recycling is fiber recovery. Fiber reclamation is extraction of fibers from textile waste and their reuse. To ensure that organic recycling is effective and that the degradation products of textile waste do not limit the quality and quantity of organic recycling products, bio-based textile waste should be biodegradable and compostable. Although waste textiles comprising a synthetic polymers fractions are considered a threat to the environment. However, their biodegradable part has great potential for production of biological products (e.g., ethanol and biogas, enzyme synthesis). A bio-based textile waste management system should promote the development and application of novel recycling techniques, such as further development of biochemical recycling processes and the textile waste should be preceded by recovery of non-biodegradable polymers to avoid contaminating the bioproducts with nano and microplastics.
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Yankova, Hristiyana. "Bio and Eco Products." Vocational Education 23, no. 1 (February 15, 2021): 94–105. http://dx.doi.org/10.53656/voc21.17bio.
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In this article (topic) we will consider how bio and eco products are produced and why they are important part of our food chain. The organic farming represents a sistem for producing agricultural products, that serves the reconstruction and recycling of the natural resources. This kind of manufacture is saving the environment, because it’s forbidden the usage of synthetic pesticides, herbicides, fertilizers, growth regulators and genetically modified organisms, antibiotics and hormones. In the field of animal husbandry the organic farming lays on the natural way of nurturing animals. Foods from plant and animal origin are called organic, when they’re produced by a person who has certificate for organic manufacturing, when following the rules for organic manufacturing and performing control.
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Milosavljevic, Milutin, Ivan Vukicevic, Sasa Drmanic, Jasmina Nikolic, Aleksandar Marinkovic, Sanja Krstic, and Slobodan Petrovic. "Simple one-pot synthesis of thioureas from amine, carbon disulfide and oxidants in water." Journal of the Serbian Chemical Society 81, no. 3 (2016): 219–31. http://dx.doi.org/10.2298/jsc150831087m.
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The present study reports the new facile methodology for synthesis of symmetrical and asymmetrical thioureas by an one-pot reaction of amine, carbon disulfide and oxidants: hydrogen peroxide, ethylenediamine tetraacetic acid (EDTA)/sodium percarbonate system or air. The structures of the synthesized compounds were confirmed by IR, 1H and 13C NMR and MS methods. Reaction mechanism has been proposed on the basis of reaction intermediate isolation and their structure determination. The synthetic benefits of the presented methods is reflected in the operational simplicity, mild reaction conditions, short reaction times, recycling of solvent, high purity and yield of products, absence of dangerous by-products and technological applicability at industrial scale. Considering commercial importance of the thioureas, it can be emphasized that implementation of the optimal synthesis of thiourea, based on presented methods, at industrial level of production would provide concurrent alternative to existing technologies in use.
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Shi, Junjie, Chao Peng, Min Chen, Yun Li, Hurman Eric, Lassi Klemettinen, Mari Lundström, Pekka Taskinen, and Ari Jokilaakso. "Sulfation Roasting Mechanism for Spent Lithium-Ion Battery Metal Oxides Under SO2-O2-Ar Atmosphere." JOM 71, no. 12 (September 25, 2019): 4473–82. http://dx.doi.org/10.1007/s11837-019-03800-5.
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Abstract Sulfation roasting followed by water leaching has been proposed as an alternative route for recycling valuable metals from spent lithium-ion batteries (LIBs). In the present work, the reaction mechanism of the sulfation roasting of synthetic LiCoO2 was investigated by both thermodynamic calculations and roasting experiments under flowing 10% SO2-1% O2-89% Ar gas atmosphere at 700°C. The products and microstructural evolution processes were characterized by x-ray diffraction, scanning electron microscope and energy dispersive x-ray spectrometer, and atomic absorption spectroscopy. It was confirmed that Co3O4 was formed as an intermedia product, and the final roasted products were composed by Li2SO4, Li2Co(SO4)2, and CoO. The leaching results indicated that 99.5% Li and 17.4% Co could be recovered into water after 120 min of roasting. The present results will provide the basis and solid guidelines for recycling of Li and Co from spent LIBs.
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Genêt, Jean-Pierre, Sylvain Darses, and Véronique Michelet. "Organometallic catalysts in synthetic organic chemistry: From reactions in aqueous media to gold catalysis." Pure and Applied Chemistry 80, no. 5 (January 1, 2008): 831–44. http://dx.doi.org/10.1351/pac200880050831.
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Water has attracted significant attention as an alternative solvent for transition-metal-catalyzed reactions. The use of water as solvent allows simplified procedures for separation of the catalyst from the products and recycling of the catalyst. Water is an inexpensive reagent for the formation of oxygen-containing products such as alcohols. The use of water as a medium for promoting organometallic and organic reactions is also of great potential. This chapter will focus on old and recent developments in the design and applications of some catalytic reactions using aqueous-phase Pd, Rh, Pt, and Au complexes.
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Zimmermann, Wolfgang. "Biocatalytic recycling of polyethylene terephthalate plastic." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 378, no. 2176 (July 6, 2020): 20190273. http://dx.doi.org/10.1098/rsta.2019.0273.
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The global production of plastics made from non-renewable fossil feedstocks has grown more than 20-fold since 1964. While more than eight billion tons of plastics have been produced until today, only a small fraction is currently collected for recycling and large amounts of plastic waste are ending up in landfills and in the oceans. Pollution caused by accumulating plastic waste in the environment has become worldwide a serious problem. Synthetic polyesters such as polyethylene terephthalate (PET) have widespread use in food packaging materials, beverage bottles, coatings and fibres. Recently, it has been shown that post-consumer PET can be hydrolysed by microbial enzymes at mild reaction conditions in aqueous media. In a circular plastics economy, the resulting monomers can be recovered and re-used to manufacture PET products or other chemicals without depleting fossil feedstocks and damaging the environment. The enzymatic degradation of post-consumer plastics thereby represents an innovative, environmentally benign and sustainable alternative to conventional recycling processes. By the construction of powerful biocatalysts employing protein engineering techniques, a biocatalytic recycling of PET can be further developed towards industrial applications. This article is part of a discussion meeting issue ‘Science to enable the circular economy’.
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Capeness, Michael J., and Louise E. Horsfall. "Synthetic biology approaches towards the recycling of metals from the environment." Biochemical Society Transactions 48, no. 4 (July 6, 2020): 1367–78. http://dx.doi.org/10.1042/bst20190837.
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Metals are a finite resource and their demand for use within existing and new technologies means metal scarcity is increasingly a global challenge. Conversely, there are areas containing such high levels of metal pollution that they are hazardous to life, and there is loss of material at every stage of the lifecycle of metals and their products. While traditional resource extraction methods are becoming less cost effective, due to a lowering quality of ore, industrial practices have begun turning to newer technologies to tap into metal resources currently locked up in contaminated land or lost in the extraction and manufacturing processes. One such technology uses biology for the remediation of metals, simultaneously extracting resources, decontaminating land, and reducing waste. Using biology for the identification and recovery of metals is considered a much ‘greener’ alternative to that of chemical methods, and this approach is about to undergo a renaissance thanks to synthetic biology. Synthetic biology couples molecular genetics with traditional engineering principles, incorporating a modular and standardised practice into the assembly of genetic parts. This has allowed the use of non-model organisms in place of the normal laboratory strains, as well as the adaption of environmentally sourced genetic material to standardised parts and practices. While synthetic biology is revolutionising the genetic capability of standard model organisms, there has been limited incursion into current practices for the biological recovery of metals from environmental sources. This mini-review will focus on some of the areas that have potential roles to play in these processes.
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Leitner, Walter. "Recent advances in catalyst immobilization using supercritical carbon dioxide." Pure and Applied Chemistry 76, no. 3 (January 1, 2004): 635–44. http://dx.doi.org/10.1351/pac200476030635.
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Homogeneous organometallic catalysts have a great potential for the development of sustainable synthetic processes. There is, however, an urgent need for the development of new techniques to separate products and catalysts efficiently, allowing for recycling and reuse of the precious catalyst. The unique solvent properties of supercritical carbon dioxide offer new approaches for the immobilization of organometallic catalysts, many of which are suitable for efficient continuous-flow operation. Recent research in this field tries to combine the molecular nature of organometallic catalysts with the reaction-engineering aspect of multiphase catalysis.
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Čabalová, Iveta, Aleš Ház, Jozef Krilek, Tatiana Bubeníková, Ján Melicherčík, and Tomáš Kuvik. "Recycling of Wastes Plastics and Tires from Automotive Industry." Polymers 13, no. 13 (July 3, 2021): 2210. http://dx.doi.org/10.3390/polym13132210.
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Waste tires (granulate) and selected plastics from the automotive industry were evaluated by using the tertiary (pyrolysis) and quaternary (calorimetry) recovering. Pyrolysis is proving to be an environmentally friendly alternative to incineration and inefficient landfilling. Currently, the main challenges for pyrolysis of plastic waste are unavailability and inconsistent quality of feedstock, inefficient and hence costly sorting, and last but not least insufficient regulations around plastic waste management. Waste plastics and tire materials were characterized by TG/DTG analysis, Py-GC/MS analysis and calorimetry. TG analysis of the investigated materials gives the typical decomposition curves of synthetic polymers. The tested samples had the highest rate of weight loss process in the temperature range from 375 °C to 480 °C. Analytical pyrolysis of the tested polymers provided information on a wide variety of organic compounds that were released upon thermal loading of these materials without access to oxygen. Analytical pyrolysis offers valuable information on the spectrum of degradation products and their potential uses. Based on the results of calorimetry, it can be stated that the determined calorific value of selected plastic and rubber materials was ranging from 26.261 to 45.245 MJ/kg depending on the ash content and its composition.
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Pateiro, Mirian, Julián Andrés Gómez-Salazar, Mariana Jaime-Patlán, María Elena Sosa-Morales, and José M. Lorenzo. "Plant Extracts Obtained with Green Solvents as Natural Antioxidants in Fresh Meat Products." Antioxidants 10, no. 2 (January 27, 2021): 181. http://dx.doi.org/10.3390/antiox10020181.
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Plants are rich in bioactive compounds (BACs), mainly polyphenols, which are valuable choices to replace synthetic antioxidants in meat products. These natural antioxidants from plants, in the form of extracts and essential oils (EOs), have been obtained from different sources such as fruits (dragon fruit, guarana, pomegranate), vegetables, (cabbage, onion), herbs, and spices (epazote, ginger, rosemary, sage, thyme, turmeric, winter savory) by several extraction processes. However, in the context of current directives there is a notable incentive for “green” solvents to replace organic ones and conventional techniques, in order to avoid harm to the environment, operator, and consumer health. In addition, the recycling of co-products from the processing of these plant materials allow us to obtain valuable BACs from under-exploited materials, contributing to the revalorization of these wastes. The resulting extracts allow us to maintain the quality of meat products, exhibiting similar or better antioxidant properties compared to those shown by synthetic ones. Their incorporation in fresh meat products would maintain the oxidative stability, stabilizing colour parameters, decreasing the formation of metmyoglobin, lipid, and protein oxidation and the generation of lipid-derived volatile compounds, without affecting sensory attributes. In addition, these novel ingredients contribute to improve both technological and functional characteristics, thus diversifying the offer of so-called “wellness foods”. In this review, the application of plant extracts as natural antioxidants in several fresh meat products is presented, showing their efficacy as scavenging radicals and imparting additional health benefits.
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Yuksekkaya, Mehmet Emin, Gizem Celep, Gamze Dogan, Mevlut Tercan, and Basak Urhan. "A Comparative Study of Physical Properties of Yarns and Fabrics Produced from Virgin and Recycled Fibers." Journal of Engineered Fibers and Fabrics 11, no. 2 (June 2016): 155892501601100. http://dx.doi.org/10.1177/155892501601100209.
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Products that are produced by various industries such as agriculture, food, mining, chemistry, and textile cannot meet the needs of humankind since the world's population continues to grow exponentially. Furthermore, the reduction in natural resources forced researchers to produce new synthetic products by utilization of technology and led them to study recycling of existing natural resources. This study compares some properties of yarns and fabrics produced by virgin and recycled polyester and cotton fibers. Virgin cotton, recycled cotton, virgin polyester, recycled polyester fibers, and blends of these fibers were used to manufacture open end rotor yarns. Single jersey fabrics were knitted from these yarns. Physical properties of yarns and fabrics such as tensile strength, unevenness, yarn imperfections, burst strength, pilling and coefficient of kinetic friction were measured and statistically compared. Although generally the properties of yarns and fabrics produced from virgin fibers were better than that of produced from recycled fibers, producing textile products with optimum quality is stressed in this study.
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Lesnau, Anna, and Mirosław Tyliszczak. "Comparative Analysis of Fuels Derived from PE Plastic Waste with a Mixture of Plastic Recycling Waste of Codes: 1, 2, 4, 5, 6 and 7 Based on Low-Temperature Pyrolysis." Journal of KONES 26, no. 4 (December 1, 2019): 149–54. http://dx.doi.org/10.2478/kones-2019-0102.
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AbstractThanks to their numerous advantages, plastics are becoming more and more widely used in all branches of industry. The quantities of products, their packaging and, consequently, the amount of synthetic polymer waste are steadily increasing, what poses a high risk to the environment due to their long decomposition time. To reduce waste production is practically impossible, therefore it is very important to constantly implement new and improve existing methods of waste treatment. The following article presents one of the alternative methods for synthetic polymer waste treatment, which is low-temperature pyrolysis. Two pyrolysis processes were carried out. During the first experiment a polyethylene plastic material was used, in the second experiment a mixture of typical household recycling waste of codes 1, 2, 4, 5, 6, and 7 were tested. During the thermal processing, the input material undergoes a chemical transformation due to breaking of long hydrocarbon chains. At the same time, high-energy density products, such as petroleum products and gas, are produced. The main advantage of the presented method is that it allows reducing preliminary technological processes to a minimum and it is easily automated, as it reduces the process to one compact installation. The reduction of the amount of stored waste and the recovery of petroleum derivatives, are additional advantages of pyrolysis implementation. That, in consequence allows reducing consumption of fossil fuel resources.
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Ruismäki, Ronja, Anna Dańczak, Lassi Klemettinen, Pekka Taskinen, Daniel Lindberg, and Ari Jokilaakso. "Integrated Battery Scrap Recycling and Nickel Slag Cleaning with Methane Reduction." Minerals 10, no. 5 (May 13, 2020): 435. http://dx.doi.org/10.3390/min10050435.
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Innovative recycling routes are needed to fulfill the increasing demand for battery raw materials to ensure sufficiency in the future. The integration of battery scrap recycling and nickel slag cleaning by reduction with methane was experimentally researched for the first time in this study. Industrial nickel slag from the direct Outotec nickel flash smelting (DON) process was mixed with both synthetic and industrial battery scrap. The end products of the slag-scrap mixtures after reduction at 1400 °C in a CH4 (5 vol %)-N2 atmosphere were an Ni–Co–Cu–Fe metal alloy and FeOx–SiO2 slag. It was noted that a higher initial amount of cobalt in the feed mixture increased the recovery of cobalt to the metal alloy. Increasing the reduction time decreased the fraction of sulfur in the metal alloy and magnetite in the slag. After reduction, manganese was deported in the slag and most of the zinc volatilized. This study confirmed the possibility of replacing coke with methane as a non-fossil reductant in nickel slag cleaning on a laboratory scale, and the recovery of battery metals cobalt and nickel in the slag cleaning process with good yields.
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Hoffmann, Hartmut, Christoph Hein, Seok Moo Hong, and Hyun Woo So. "METAKLETT – A Metal Cocklebur." Key Engineering Materials 344 (July 2007): 677–84. http://dx.doi.org/10.4028/www.scientific.net/kem.344.677.
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The increasing individualization of products assigns manufacturing companies to new tasks like manufacturing various products in a more efficient way. This progression in the market leads on the one hand to a new product design and on the other hand to an improved production process. Both are necessary to reduce assembly, service and recycling costs. Hence the joining technology is and will become more and more important. The conventional joining technologies like welding, bonding, bolting or clamping have their own disadvantages especially in the field of flexibility. In order to reduce the effort for assembling and disassembling by retaining the requirements of the connection a new innovative joining technology is needed. In this study a new joining technology is introduced to become faster and more flexible in assembling and disassembling. The basic idea of this manufacturing technology comes from a “metal hook and loop fastener”. A hook and loop fastener consisting of metal has a lot of advantages for the fields of industrial assembly, service and recycling. Similar to the synthetic hook and loop fastener a metal one is characterized by easy closing and opening without special tools. And in comparison to the synthetic hook and loop fastener the transmissible forces are very high. An additional benefit can be gained for instance in shock absorbing or resistance against chemical and thermal influence. Two solutions are followed up to invent the “metal hook and loop fastener”. A one-to-one copy of the conventional hook and loop fastener is constructed in metal and specific solutions for the use of metal are tested. A conventional finite element program was used in order to optimize the construction of a metal cocklebur and the results show a good agreement with the experiment.
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Kumar, Krishna Kant, Saurabh Singh, Sanchari Chakraborthy, Jayashree Das, Mayur Bajaj, Varnika Hemanth, Meghna Nair, Leelakrishna Thota, and Pradipta Banerjee. "Recycling fish skin for utilization in food industry as an effective emulsifier and foam stabilizing agent." Turkish Journal of Biochemistry 44, no. 3 (October 16, 2018): 332–43. http://dx.doi.org/10.1515/tjb-2018-0084.
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Abstract Background Indian fish industry produces a staggering amount of waste every year part of which is dumped as landfill leading to pollution. Objective This study aims to extract collagen from fish skin, a major component of this waste, hydrolyze it and use the hydrolysate as emulsifiers to increase the shelf life of food products. Materials and methods Collagen was purified from the skin of Catfish, Mullet and Indian Salmon were characterized through infrared and diffraction studies. The samples were hydrolyzed enzymatically. The hydrolysates were assayed for emulsifying, foam stabilizing and hemolytic properties. Results The samples displayed an electrophoretic and infrared spectral profile corresponding to that of collagen type I. X-ray diffraction patterns revealed the presence of triple helix and traces of phosphate. The hydrolysates (6 kDa) exhibited the highest emulsion at 2.74±0.20 m2/g (for 57.00±0.50 min) and foam stability in the range of 75–78%, respectively. The hydrolysates were able to stabilize drug and food formulations successfully and two of the samples exhibited less than 3% toxicity as determined through hemolytic assay. Conclusion Collagen hydrolysates from fish skin, a common fish industry waste, were found to be bioactive and non-toxic making them suitable replacements for synthetic emulsifiers.
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Iacob, Robert, and Diana Popescu. "Method and Software for Analyzing the Assembly/Disassembly Operations of Mechanical Products." Applied Mechanics and Materials 658 (October 2014): 638–43. http://dx.doi.org/10.4028/www.scientific.net/amm.658.638.
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Enrolling in the current trends of using collaborative virtual environments and virtual reality techniques for engineering applications, the current paper presents the synthetic results of a research in which an innovative method and software application were developed for analyzing and simulating the Assembly/Disassembly (A/D) operations of mechanical products. Starting from the 3D CAD model of an assembly and using connection interface and mobility operator concepts, the application supports the designers in generating valid A/D plans by determining the interfaces between components, calculating the components mobility and identifying the functional role of components in an assembly. Thus, the developed software provides designers an automated tool for analyzing A/D operations, obtaining and simulating A/D sequences, useful in the design phase of a mechanical product, for training the operators, as well as for improving the productivity of activities such as recycling, maintenance and reusing. Moreover, the application was conceived so that, in a further step, to be integrated in an immersive environment, offering a realistic simulation in two modes of interaction: free mode and kinematically guided. Finally, in order to validate the proposed methods and concepts, the application was tested for evaluating users’ satisfaction degree.
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BEKIR, YITIK. "Quality assessment of fabrics obtained from waste." Industria Textila 73, no. 04 (August 31, 2022): 405–10. http://dx.doi.org/10.35530/it.073.04.202164.
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The need for ready-made clothing and home textiles produced from natural and synthetic fibres is increasing day by day in order to meet the needs of the increasing world population. Recently, the concepts of sustainability and recycling have gained importance in the textile industry. The rapid change in today's trends has developed disposable habits. Due to the rapidly changing fashion trends, the product variety has increased and mass production has been preferred. Therefore, the priority for customers to choose the products was not the material used, but whether they fit the current fashion trend. Thus, the use and production of natural fibres should be increased to reduce environmental pollution and meet production demand. Thanks to recycling, it is possible to reuse the waste textile materials that we leave to nature. Due to the increase in agricultural production costs, it has become difficult to obtain the raw materials used for textiles. When a life cycle system is created for raw materials that evaluate them until it is produced in nature and then return to nature, production with textile waste recycling can be advantageous. Using natural waste fibres instead of natural virgin fibres to produce home textile products both reduces costs and makes production easier. In this study, recycled (waste) cotton was obtained by shredding white, 100% cotton woven duvet covers and sheets purchased from a private hospital. A 50%-50% waste-natural blend was created from the cotton obtained. 54 wire reference fabrics were woven using open-end yarns numbered Ne24 and Ne12 produced from this blend. The physical characteristics of the fabric were investigated. The results obtained were analysed statistically and the effect of the blend created on the fabric quality was comprehensively examined.
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Albini, Giulia, Valentina Brunella, Bartolomeo Placenza, Brunetto Martorana, and Vito Guido Lambertini. "Comparative study of mechanical characteristics of recycled PET fibres for automobile seat cover application." Journal of Industrial Textiles 48, no. 6 (December 18, 2018): 992–1008. http://dx.doi.org/10.1177/1528083717750887.
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Polyethylene terephthalate is a thermoplastic polymer with a wide range of uses, including synthetic fibres and containers for beverages and other liquids. Recycling plastics reduces the amount of energy and natural resources needed to create virgin plastics. Polyethylene terephthalate containers and bottles are collected and then broken down into small flakes used to produce new products such as textile fibres. Thermo-mechanical degradation may happen during the recycling process and presence of contaminants affects the final product characteristics. Two kinds of recycled polyethylene terephthalate fibres were used for fabrics production: post-consumer polyethylene terephthalate fibres and a blend of post-consumer and post-industrial polyethylene terephthalate fibres. Focusing on knitted and flat-woven textile structures, main mechanical properties of the fabrics were assessed by various tests, like tensile strength test and wear resistance test. A comparative study with the current production of virgin polyethylene terephthalate fabrics was useful to evaluate high standards accordance for automotive field. Both knitted and flat-woven recycled polyethylene terephthalate fabrics had excellent performance after mechanical tests. Post-consumer polyethylene terephthalate fabrics had the best results, especially after wear resistance test. These results allow an evaluation of their applications.
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Hurt, Andrew P., Aimee A. Coleman, Haosen Ma, Qiu Li, and Nichola J. Coleman. "Calcium Silicate Hydrate Cation-Exchanger from Paper Recycling Ash and Waste Container Glass." Ceramics 5, no. 3 (July 22, 2022): 301–17. http://dx.doi.org/10.3390/ceramics5030024.
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Synthetic 11 Å tobermorite (Ca5Si6O16(OH)2.4H2O) and its Al-substituted analogue are layer-lattice ion-exchangers with potential applications in nuclear and hazardous wastewater treatment. The present study reports the facile one-pot hydrothermal synthesis of an Al-tobermorite-rich cation-exchanger from a combination of paper recycling ash, post-consumer container glass, and lime, with compositional ratios of [Ca]/[Si + Al] = 0.81 and [Al]/[Si + Al] = 0.18. The reaction products were characterized by powder X-ray diffraction analysis, 29Si magic angle spinning nuclear magnetic resonance spectroscopy, and scanning electron microscopy. Hydrothermal processing in 4 M NaOH(aq) at 100 °C for 7 days yielded an Al-tobermorite-rich product that also contained katoite (Ca3Al2SiO12H8), portlandite (Ca(OH)2), calcite (CaCO3), and amorphous silicate gel. The hydrothermal product was found to have a Cs+ cation exchange capacity of 59 ± 4 meq 100 g−1 and selective Cs+ distribution coefficients (Kd) of 574 ± 13 and 658 ± 34 cm3 g−1 from solutions with molar ratios [Cs+]:[Na+] and [Cs+]:[Ca2+] of 1:100. In a batch sorption study at 20 °C, the uptakes of Pb2+, Cd2+, and Cs+ were determined to be 1.78 ± 0.04, 0.65 ± 0.06, and 0.36 ± 0.03 mmol g−1, respectively. The kinetics of Pb2+, Cd2+, and Cs+ removal were described by the pseudo-second-order rate model, which gave respective rate constants (k2) of 0.010, 0.027, and 1.635 g mmol−1 min−1, and corresponding correlation coefficients (R2) of 0.997, 0.996, and 0.999. The metal ion sorption properties of the tobermorite-rich product compared favorably with those of other waste-derived tobermorites reported in the literature. Potential strategies to improve the yield, crystallinity, and sorption characteristics of the product are discussed.
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Nuryawan, Arif, Jajang Sutiawan, Rahmawaty, Nanang Masruchin, and Pavlo Bekhta. "Panel Products Made of Oil Palm Trunk: A Review of Potency, Environmental Aspect, and Comparison with Wood-Based Composites." Polymers 14, no. 9 (April 26, 2022): 1758. http://dx.doi.org/10.3390/polym14091758.
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Oil palm plantations have expanded rapidly in Southeast Asia, particularly in Indonesia and Malaysia. A lot of products, including food and other edible products, oleo-chemicals, cosmetics, personal and household care, pharmaceutical products, and biodiesels are derived from palm oil, thus making them one of the most economically important plants. After 25–30 years of age, the palms are felled and replaced due to declining oil production. Oil palm trunks (OPT) are considered significant waste products. The trunks remain on the plantation site for nutrient recycling or burning. This increases insect and fungi populations causing environmental problems for the new palm generation or air pollution due to the fire. Up till now, OPT has received less attention in research studies. Therefore, this review summarizes the utilization of OPT into products made of oil palm fibers mainly derived from OPT and its application as the substitution of wood panel products. Some research works have been carried out on oil palm fibers that are derived from OPT for exploiting their potential as raw material of composite panel products, which is the objective of this review. Areas of development are processed into various conventional composite panel products such as plywood and laminated board which are usually predominantly made of wood and bonded by synthetic resins, particleboard with binder, or binderless and cement board which is arranged with wood as a minor component. All of the products have been presented and described technically according to best knowledge of the authors and literature review.
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Cheung, Hoi Yan, and Alan Kin Tak Lau. "Mechanical Performance of Silk-Based Structural Composites." Key Engineering Materials 326-328 (December 2006): 457–60. http://dx.doi.org/10.4028/www.scientific.net/kem.326-328.457.
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With the strong emphasis on environmental awareness, it has brought much attention in the development of recyclable and environmentally sustainable composite materials since the last decade. Environmental legislation as well as consumer demand in many countries is increasing the pressure on manufacturers of materials and end-products to consider the environmental impact of their products at all stages of their life cycle, including recycling and ultimate disposal. Silk fibers, spun out from silkworm cocoons, consist of a fibroin core surrounded by a protein layer called "sericin", and these fibers are biodegradable and highly crystalline. It has been known that these fibers have higher tensile strength and are more predictable in failure than glass and synthetic organic fibers. Recently, few preliminary studies have reported that the use of these silks, as microreinforcements to replace un-recyclable carbon and glass fibers for polymeric-based structural composite materials can enhance their mechanical and thermal properties, with reducing the amount of un-decomposable wastes and pollutants. In this paper, the mechanical properties of silk-based epoxy composites formed by different controlled manufacturing parameters are elaborately studied.
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Ruuth, Edvin, Miguel Sanchis-Sebastiá, Per Tomas Larsson, Anita Teleman, Amparo Jiménez-Quero, Sara Delestig, Viktor Sahlberg, et al. "Reclaiming the Value of Cotton Waste Textiles: A New Improved Method to Recycle Cotton Waste Textiles via Acid Hydrolysis." Recycling 7, no. 4 (August 12, 2022): 57. http://dx.doi.org/10.3390/recycling7040057.
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The fashion industry is becoming one of the largest emitters worldwide due to its high consumption of raw materials, its effluents, and the fact that every garment will eventually contribute to the vast amount of waste being incinerated or accumulating in landfills. Although fiber-to-fiber recycling processes are being developed, the mechanical properties of the textile fibers are typically degraded with each such recycle. Thus, tertiary recycling alternatives where textiles are depolymerized to convert them into valuable products are needed to provide end-of-life alternatives and to achieve circularity in the fashion industry. We have developed a method whereby cotton waste textiles are depolymerized to form a glucose solution, using sulfuric acid as the sole catalyst, with a high yield (>70%). The glucose solution produced in this process has a high concentration (>100 g/L), which reduces the purification cost and makes the process industrially relevant. This method can be applied regardless of the quality of the fibers and could therefore process other cellulosic fibers such as viscose. The glucose produced could subsequently be fermented into butanediol or caprolactam, precursors for the production of synthetic textile fibers, thus retaining the value of the waste textiles within the textile value chain.
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Bugnicourt, E., M. Schmid, O. Mc Nerney, J. Wildner, L. Smykala, A. Lazzeri, and P. Cinelli. "Processing and Validation of Whey-Protein-Coated Films and Laminates at Semi-Industrial Scale as Novel Recyclable Food Packaging Materials with Excellent Barrier Properties." Advances in Materials Science and Engineering 2013 (2013): 1–10. http://dx.doi.org/10.1155/2013/496207.
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A biopolymer coating for plastic films was formulated based on whey protein, and its potential to replace current synthetic oxygen barrier layers used in food packaging such as ethylene vinyl alcohol copolymers (EVOH) was tested. The whey-coating application was performed at semi-industrial scale. High barrier to oxygen with transmission rate down to ranges of 1 cm3(STP) m−2d−1bar−1at and 50% relative humidity (r.h.) but interesting humidity barrier down to ranges of 3 g m−2d−1(both normalized to 100 μm thickness) were reached, outperforming most existing biopolymers. Coated films were validated for storing various food products showing that the shelf life and sensory attributes were maintained similar to reference packaging films while complying with food safety regulations. The developed whey coating could be enzymatically removed within 2 hours and is therefore compatible with plastic recycling operations to allow multilayer films to become recyclable by separating the other combined layers. A life cycle assessment was performed showing a significant reduction in the environmental impact of the packaging thanks in particular to the possibility of recycling materials as opposed to incinerating those containing EVOH or polyamide (PA), but due to the use of biosourced raw materials.
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Wang, L., and S. J. Khan. "Enantioselective analysis and fate of polycyclic musks in a water recycling plant in Sydney (Australia)." Water Science and Technology 69, no. 10 (February 21, 2014): 1996–2003. http://dx.doi.org/10.2166/wst.2014.095.
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Synthetic polycyclic musks (PCMs) Galaxolide (HHCB), Tonalide (AHTN), Phantolide (AHDI), Traseolide (ATII) and Cashmeran (DPMI) are chiral chemicals that are commonly used in washing product industries as racemic mixtures. The major source of PCMs in municipal wastewater is from personal care and household products. Recent studies have shown that PCMs may enhance the relative toxicity of other environmental chemicals by inhibiting cellular xenobiotic defence systems. High sensitivity enantioselective analysis of these compounds enables improved characterisation of the environmental persistence and fate of PCMs, distinguishing between individual enantiomers so that a more complete understanding of environmental risks tributed by individual enantiomers may be obtained. Concentrations of PCMs through the various treatment stages of an advanced water recycling plant in Sydney were investigated to assess the removal of these chemicals. Average concentrations of HHCB, AHTN, AHDI, ATII and DPMI in influent were: 2,545, 301, 2, 5 and 33 ng L−1, respectively. In the final effluent, AHDI, ATII and DPMI were not detected, while HHCB and AHTN were still measured at concentrations of 21 and 2 ng L−1. No significant enantioselective transformation was detected during biological or advanced treatment processes.
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Panek, H. R., E. Conibear, J. D. Bryan, R. T. Colvin, C. D. Goshorn, and L. C. Robinson. "Identification of Rgp1p, a novel Golgi recycling factor, as a protein required for efficient localization of yeast casein kinase 1 to the plasma membrane." Journal of Cell Science 113, no. 24 (December 15, 2000): 4545–55. http://dx.doi.org/10.1242/jcs.113.24.4545.
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The Yck1p and Yck2p casein kinase 1 isoforms in yeast are essential peripheral plasma membrane-associated protein kinases with roles in endocytosis, cellular morphogenesis and cytokinesis. The membrane targeting of these cytoplasmically oriented protein kinases requires normal secretory pathway function, but specific targeting factors have not been identified. To learn more about Yckp targeting, we characterized mutations that cause synthetic lethality with impairment of Yck function. We report here that these include mutations in two gene products that function in protein trafficking. One of these is the previously described t-SNARE Tlg2p, which participates in recycling of proteins to the Golgi. The other is a previously uncharacterized protein, Rgp1p, which appears to have a similar function. Loss of either Tlg2p or Rgp1p causes inefficient localization of Yck2p, suggesting that its transport may be directed, in part, by a targeting factor that must be recycled back to the Golgi.
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Rusling, James F. "Green synthesis via electrolysis in microemulsions." Pure and Applied Chemistry 73, no. 12 (January 1, 2001): 1895–905. http://dx.doi.org/10.1351/pac200173121895.
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Electrolysis in microemulsions is a promising approach for environmentally friendly chemical synthetic methods of the future. Employing microemulsions instead of organic solvents for electrosynthesis has the advantages of lower toxicity and cost, high dissolving power for reactants and mediators of unlike solubility, enhancement of reaction rates by controlling the reduction potentials of mediators, possible reaction pathway control, and recycling of microemulsion components. This paper reviews recent progress in using microemulsions for direct and mediated electrosynthesis, including formation of carboncarbon bonds. Rates of mediated reactions can be controlled by manipulating microemulsion composition. Examples are presented, in which reaction pathways of direct and mediated electrolyses can be controlled with microemulsions to give desired products in high yields. Such control has been demonstrated with dissolved and surface-bound mediators. For a covalently linked scaffold of poly(l-lysine) and cobalt corrin vitamin B12 hexacarboxylate attached to graphite, catalytic turnover rate for reduction of 1,2-dibromocylcohexane was optimized by optimizing microemulsion composition.
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Choi, Young In, Ju Hyun Yang, So Jeong Park, and Youngku Sohn. "Energy Storage and CO2 Reduction Performances of Co/Co2C/C Prepared by an Anaerobic Ethanol Oxidation Reaction Using Sacrificial SnO2." Catalysts 10, no. 10 (September 25, 2020): 1116. http://dx.doi.org/10.3390/catal10101116.
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Co/Co2C/C hybrids were prepared employing a new synthetic route and demonstrated as materials for energy storage and CO2 recycling application. Herein, an anaerobic ethanol oxidation reaction over Co3O4 nanoparticles (NPs) was first employed to fabricate Co/Co2C/C hybrids using sacrificial SnO2. In the absence of SnO2, Co3O4 NPs were converted to alpha and beta metallic Co. On the other hand, using sacrificial SnO2 resulted in the formation of Co2C and Co embedded in the carbon matrix at approximately 450 °C, as determined by temperature-programmed mass spectrometry analysis. The newly developed materials were fully examined by X-ray diffraction crystallography, scanning electron microscopy, energy-dispersive X-ray analysis, high-resolution transmission electron microscopy, and X-ray photoelectron spectroscopy. The Co/Co2C/C hybrids showed a specific capacitance of 153 F/g at a current density of 0.5 A/g. Photocatalytic CO2 reduction experiments were performed and generated CO, CH4, and CH3OH as reduction products with yields of 47.7, 11.0, and 23.4 μmol/g, respectively. The anaerobic ethanol oxidation reaction could be a very useful method for the development of carbon-supported metal carbides, which have not been achieved by other synthetic methods. Furthermore, the demonstration tests unveiled new application areas of Co carbide materials.
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Andrade, Marta A., and Luísa M. D. R. S. Martins. "Sustainability in Catalytic Cyclohexane Oxidation: The Contribution of Porous Support Materials." Catalysts 10, no. 1 (December 18, 2019): 2. http://dx.doi.org/10.3390/catal10010002.
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The development of green and sustainable protocols for synthetic routes is a growing area of research in chemistry worldwide. The development of sustainable processes and products through innovative catalytic materials and technologies, that allow a better use of resources, is undoubtedly a very important issue facing research chemists today. Environmentally and economically advanced catalytic processes for selective alkane oxidations reactions, as is the case of cyclohexane oxidation, are now focused on catalysts’ stability and their reuse, intending to overcome the drawbacks posed by current homogeneous systems. The aim of this short review is to highlight recent contributions in heterogeneous catalysis regarding porous support materials to be applied to cyclohexane oxidation reaction. Different classes of porous materials are covered, from carbon nanomaterials to zeolites, mesoporous silicas, and metal organic frameworks. The role performed by the materials to be used as supports towards an enhancement of the activity/selectivity of the catalytic materials and the ability of recycling and reuse in consecutive catalytic cycles is highlighted.
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Kyselka, J., L. Thomes, S. Remišová, M. Dragoun, M. Berčíková, and V. Filip. "Preparation of conjugated linoleic acid enriched derivatives by conventional and biphasic isomerisation." Czech Journal of Food Sciences 34, No. 6 (December 21, 2016): 511–21. http://dx.doi.org/10.17221/362/2016-cjfs.
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The preparation of conjugated linoleic acid (CLA)-enriched free fatty acids by industrial processes compared with our biphasic isomerisation experiments in a special designed reactor enabling the preparation of CLA esters was evaluated. Our experiments further revealed the main disadvantage of semi-synthetic alkali isomerisation to be the formation of conjugated E,E-octadecadienoic acid isomers (2.92–3.44%) and the bioavailability of free fatty acid products. Urea fractionation technology improved the quality of the reaction mixture, but at the same time the yield of rumenic acid was decreased on purification. Therefore, we decided to apply complexes of noble metals in order to isomerise linoleic acid ester derivatives. The known Wilkinson’s hydrogenation catalyst, RhCl (PPh<sub>3</sub>)<sub>3</sub>, was found to be the most effective. We investigated the preparation of bioavailable CLA-enriched triacylglycerols. Special attention was paid to recycling of Wilkinson’s catalyst.
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Toncheva, Antoniya, Loïc Brison, Philippe Dubois, and Fouad Laoutid. "Recycled Tire Rubber in Additive Manufacturing: Selective Laser Sintering for Polymer-Ground Rubber Composites." Applied Sciences 11, no. 18 (September 21, 2021): 8778. http://dx.doi.org/10.3390/app11188778.
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Natural and synthetic rubber is gaining increased interest in various industrial applications and daily life sectors (automotive industry, acoustic and electrical isolators, adhesives, impermeable surfaces, and others) due to its remarkable physicomechanical properties, excellent durability, and abrasive resistance. These great characteristics are accompanied by some recycling difficulties of the final products, particularly originated from the tire waste rubber industry. In this study, recycled tire rubber was incorporated in polymer matrices using selective laser sintering as 3D printing technology. Two polymers were used-polyamide and thermoplastic polyurethane, for their rigid and elastomeric properties, respectively. Polymer composites containing various tire powder amounts, up to 40 wt.%, were prepared by physical blending. The final materials’ morphological characteristics, mechanical properties, and thermal stability were evaluated. The proposed ambitious additive manufacturing approach looked over also some of the major aspects to be considered during the 3D printing procedure. In addition, examples of printed prototypes with potential applications were also proposed revealing the potential of the recycled tire rubber-loaded composites.
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Setiati, Rini, S. Kasmungin, Sabrina S. Riswati, Astri Rinanti, and Jochanan Satriabudi. "THE PERFORMANCE EFFECTS OF SOLID WASTE FROM BAGASSE ON INCREASED OIL RECOVERY." INDONESIAN JOURNAL OF URBAN AND ENVIRONMENTAL TECHNOLOGY 4, no. 2 (April 6, 2021): 183. http://dx.doi.org/10.25105/urbanenvirotech.v4i2.9195.
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<p><strong>Aims:</strong><strong> </strong>This study aims to determine the synthesis of bagasse to form surfactants and evaluation of the performance of the sample to increase oil yield. Indonesia generates very large amounts of solid waste, without recycling or adequate management efforts to preserve the environment. Bagasse emerged as one of the most abundant biomass due to the operations of large plantations and factories. Furthermore, previous studies showed extensive uses in the fields of compost, animal feed, bioethanol energy, paper, and reinforced building materials. <strong>Methodology and Results:</strong> Lignin was extracted from bagasse to process sodium lignosulfonate surfactant (SLS surfactant). The synthesis was characterized several times, and certain examples showed significant HLB values, as a function of emulsion builder. This condition in the oil reservoir is required to reduce interface stress (IFT) and friction in the movement of particles. Another analyses involves the assessment of core flooding of specific synthetic core and crude samples. <strong>Conclusion, significance and impact of study:</strong> The results confirm the ability of surfactant bagasse to increase oil recovery, namely the HLB value of 11.6. The results also show the surfactant classification with the ability to form a middle-phase emulsion in order to increase petroleum products. Therefore, bagasse as solid waste has a performance effect on the process of increasing petroleum production.</p>
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Ňancucheo, I., S. Hedrich, and D. B. Johnson. "New microbiological strategies that enable the selective recovery and recycling of metals from acid mine drainage and mine process waters." Mineralogical Magazine 76, no. 7 (December 2012): 2683–92. http://dx.doi.org/10.1180/minmag.2012.076.7.04.
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AbstractApproaches currently used for remediating acid mine drainage (chiefly active chemical treatment and passive bioremediation systems) have a number of major detractions, including their failure to recover potentially valuable metals from these waters. Bioremediation strategies that utilize reactor-housed microorganisms can circumvent this problem, but have tended not to be widely used due to their relatively high costs. We have devised innovative approaches for remediating mine waters that use acidophilic bacteria to remove metals either as oxidized or reduced phases, using modular bioreactors that are designed to operate at minimal cost and to generate products that have commercial value. A composite system is described that combines microbial oxidation of ferrous iron with abiotic precipitation of ferric iron as schwertmannite, a mineral that has commercial value as an absorbent of arsenate and other environmental pollutants, and as a pigment. Sulfidogenic bioreactors maintained at acidic pH values are used to selectively precipitate metal sulfides, such as CuS. Tests with synthetic mine drainage containing mixtures of soluble metals confirmed that these systems can generate relatively pure mineral deposits from complex acid waters. The units are designed to be configured differently, according to the nature of the mine water requiring treatment.
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Wu, Hao, Jingdan Liang, Lixia Gou, Qiulin Wu, Wei-Jun Liang, Xiufen Zhou, Ian J. Bruce, Zixin Deng, and Zhijun Wang. "Recycling of Overactivated Acyls by a Type II Thioesterase during Calcimycin Biosynthesis in Streptomyces chartreusis NRRL 3882." Applied and Environmental Microbiology 84, no. 12 (April 13, 2018): e00587-18. http://dx.doi.org/10.1128/aem.00587-18.
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ABSTRACT Type II thioesterases typically function as editing enzymes, removing acyl groups that have been misconjugated to acyl carrier proteins during polyketide secondary metabolite biosynthesis as a consequence of biosynthetic errors. Streptomyces chartreusis NRRL 3882 produces the pyrrole polyether ionophoric antibiotic, and we have identified the presence of a putative type II thioesterase-like sequence, calG, within the biosynthetic gene cluster involved in the antibiotic's synthesis. However, targeted gene mutagenesis experiments in which calG was inactivated in the organism did not lead to a decrease in calcimycin production but rather reduced the strain's production of its biosynthetic precursor, cezomycin. Results from in vitro activity assays of purified, recombinant CalG protein indicated that it was involved in the hydrolysis of cezomycin coenzyme A (cezomycin-CoA), as well as other acyl CoAs, but was not active toward 3-S-N-acetylcysteamine (SNAC; the mimic of the polyketide chain-releasing precursor). Further investigation of the enzyme's activity showed that it possessed a cezomycin-CoA hydrolysis Km of 0.67 mM and a kcat of 17.77 min−1 and was significantly inhibited by the presence of Mn2+ and Fe2+ divalent cations. Interestingly, when S. chartreusis NRRL 3882 was cultured in the presence of inorganic nitrite, NaNO2, it was observed that the production of calcimycin rather than cezomycin was promoted. Also, supplementation of S. chartreusis NRRL 3882 growth medium with the divalent cations Ca2+, Mg2+, Mn2+, and Fe2+ had a similar effect. Taken together, these observations suggest that CalG is not responsible for megasynthase polyketide precursor chain release during the synthesis of calcimycin or for retaining the catalytic efficiency of the megasynthase enzyme complex as is supposed to be the function for type II thioesterases. Rather, our results suggest that CalG is a dedicated thioesterase that prevents the accumulation of cezomycin-CoA when intracellular nitrogen is limited, an apparently new and previously unreported function of type II thioesterases. IMPORTANCE Type II thioesterases (TEIIs) are generally regarded as being responsible for removing aberrant acyl groups that block polyketide production, thereby maintaining the efficiency of the megasynthase involved in this class of secondary metabolites' biosynthesis. Specifically, this class of enzyme is believed to be involved in editing misprimed precursors, controlling initial units, providing key intermediates, and releasing final synthetic products in the biosynthesis of this class of secondary metabolites. Our results indicate that the putative TEII CalG present in the calcimycin (A23187)-producing organism Streptomyces chartreusis NRRL 3882 is not important either for the retention of catalytic efficiency of, or for the release of the product compound from, the megasynthase involved in calcimycin biosynthesis. Rather, the enzyme is involved in regulating/controlling the pool size of the calcimycin biosynthetic precursor, cezomycin, by hydrolysis of its CoA derivative. This novel function of CalG suggests a possible additional activity for enzymes belonging to the TEII protein family and promotes better understanding of the overall biosynthetic mechanisms involved in the production of this class of secondary metabolites.
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Glazkov, S. V., S. V. Koptsev, N. A. Lesnikova, V. V. Bogdanova, and T. K. Volodarskaya. "MODERN INNOVATIVE STORAGE TECHNOLOGIES FOR PROCESSED FRUIT AND VEGETABLE PRODUCTS (REVIEW)." Vegetable crops of Russia, no. 5 (December 4, 2018): 84–89. http://dx.doi.org/10.18619/2072-9146-2018-5-84-89.
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The article analyzes modern technologies for storing fruit and vegetable products and presents possible options for their modernization. From this perspective, the improvement of canning technology using non-traditional methods of processing plant raw materials is an urgent task, the solution of which will allow preserving fruit and vegetable products, reduce the amount of waste and reduce the impact of vegetable processing plants on natural water bodies. Fruits and vegetables are perishable products and require special storage conditions from the moment they are available for sale to purchase by consumers. Keeping them fresh for as long as possible is quite a challenge, as some plants are able to continue maturing even after packaging and produce ethylene, which initiates certain changes in texture and color, tissue degradation. The authors pay special attention to the aspects of innovative technologies in the creation of edible films and coatings, which are currently the only type of biodegradable polymer packaging that does not require individual collection and special conditions of disposal. This is their main difference from traditional biodegradable plastics, which were originally proposed as an alternative to synthetic polymeric materials, and all were convinced that their creation once and for all will solve the problem of waste polymer packaging, which today threatens to become a global environmental disaster. At the same time, they are always more expensive than conventional plastics, in many cases can not be subjected to joint recycling; being in the deep layers of the landfill, they emit greenhouse gas methane. In addition, the raw materials for biodegradable plastics are provided by the same soil and water resources on which food is grown today (except for a very small amount of plastics produced from agricultural waste), and therefore their raw material base will always be limited. Recommendations are formulated on the organization of effective conservation of plant raw materials, intended for further processing or sale in retail and wholesale trade networks.
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Šuput, Danijela, Senka Popović, Jovana Ugarković, and Nevena Hromiš. "Application of life cycle assessment in the packaging sector for the environmental assessment of polymer and biopolymer based materials: A review." Journal on Processing and Energy in Agriculture 26, no. 2 (2022): 75–78. http://dx.doi.org/10.5937/jpea26-39342.
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Among many important requirements for packaging materials, environmental friendliness is a property that has become necessary for any material that needs to be competitive in the market. Life Cycle Analysis (LCA) is an analytical instrument that provides a framework for analyzing the impact of products and services on the environment, i.e. provides an understanding and the possibility of comparing different products. LCA studies the use of resources and the consequent emissions of pollutants on the environment during the entire life of a product from raw materials exploitation, through production, use and treatment at the end of the life cycle - recycling and final disposal. This paper will provide an overview of the LCA results of various commercial polymer packaging materials, as well as the results of LCAs of biopolymer materials. Although LCA faces the problem of data heterogeneity, since some studies focused on individual segments of the analysis, while some related to all aspects of the process, as well with the problem of interpreting heterogeneous results, because the output parameters were arbitrarily selected by the researcher, still it could be concluded that the available LCA studies and environmental assessments support further development of biobased polymers. When comparing biopolymer materials with commercial synthetic polymers, they have advantages - lower consumption of fossil fuels and lower emission rate of greenhouse gases from the whole life cycle.
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Berthelot, Curtis, and Ron Gerbrandt. "Full-Depth In-Place Recycling and Road Strengthening Systems for Low-Volume Roads: Highway No. 19 Case Study." Transportation Research Record: Journal of the Transportation Research Board 1819, no. 1 (January 2003): 32–43. http://dx.doi.org/10.3141/1819b-05.
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The province of Saskatchewan has the highest number of public roads per capita in Canada, totaling approximately 198,700 km. The Saskatchewan Department of Highways and Transportation manages approximately 26,100 km of these public roads. As with most public road agencies, the department has limited resources for managing this relatively large network of low-volume roads and therefore continually strives to research and implement more cost-effective and technically feasible solutions. Of particular concern are approximately 7,500 km of thin membrane surface (TMS) roads that are undergoing accelerated damage as truck traffic and loading increase. Although conventional TMS upgrading strategies are normally effective, there are potentially significant benefits to be gained with implementation of more cost-effective methods of road strengthening. Systems include granular soil strengthening and applications of different cement products, lime, various grades of fly ash, geotextiles, geogrids, natural and manufactured fibers, emulsified bitumen, tall oil, lignin, foamed bitumen, and synthetic ionic and cationic chemicals. Since 1999, in conjunction with Pavement Scientific International and in cooperation with the University of Saskatchewan and product suppliers, the department has constructed pilot projects on Highway No. 19 to identify, develop, and implement more cost-effective strengthening systems. The primary research objective is to investigate alternative road construction systems that will improve the load-carrying capacity and environmental durability of Saskatchewan TMS roads. Improved mechanistic engineering methods played a part in this initiative, and pilot project performance was monitored.
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Saygin, Deger, and Dolf Gielen. "Zero-Emission Pathway for the Global Chemical and Petrochemical Sector." Energies 14, no. 13 (June 23, 2021): 3772. http://dx.doi.org/10.3390/en14133772.
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The chemical and petrochemical sector relies on fossil fuels and feedstocks, and is a major source of carbon dioxide (CO2) emissions. The techno-economic potential of 20 decarbonisation options is assessed. While previous analyses focus on the production processes, this analysis covers the full product life cycle CO2 emissions. The analysis elaborates the carbon accounting complexity that results from the non-energy use of fossil fuels, and highlights the importance of strategies that consider the carbon stored in synthetic organic products—an aspect that warrants more attention in long-term energy scenarios and strategies. Average mitigation costs in the sector would amount to 64 United States dollars (USD) per tonne of CO2 for full decarbonisation in 2050. The rapidly declining renewables cost is one main cause for this low-cost estimate. Renewable energy supply solutions, in combination with electrification, account for 40% of total emissions reductions. Annual biomass use grows to 1.3 gigatonnes; green hydrogen electrolyser capacity grows to 2435 gigawatts and recycling rates increase six-fold, while product demand is reduced by a third, compared to the reference case. CO2 capture, storage and use equals 30% of the total decarbonisation effort (1.49 gigatonnes per year), where about one-third of the captured CO2 is of biogenic origin. Circular economy concepts, including recycling, account for 16%, while energy efficiency accounts for 12% of the decarbonisation needed. Achieving full decarbonisation in this sector will increase energy and feedstock costs by more than 35%. The analysis shows the importance of renewables-based solutions, accounting for more than half of the total emissions reduction potential, which was higher than previous estimates.
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Loffredo, Elisabetta. "Recent Advances on Innovative Materials from Biowaste Recycling for the Removal of Environmental Estrogens from Water and Soil." Materials 15, no. 5 (March 3, 2022): 1894. http://dx.doi.org/10.3390/ma15051894.
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New technologies have been developed around the world to tackle current emergencies such as biowaste recycling, renewable energy production and reduction of environmental pollution. The thermochemical and biological conversions of waste biomass for bioenergy production release solid coproducts and byproducts, namely biochar (BC), hydrochar (HC) and digestate (DG), which can have important environmental and agricultural applications. Due to their physicochemical properties, these carbon-rich materials can behave as biosorbents of contaminants and be used for both wastewater treatment and soil remediation, representing a valid alternative to more expensive products and sophisticated strategies. The alkylphenols bisphenol A, octylphenol and nonylphenol possess estrogenic activity comparable to that of the human steroid hormones estrone, 17β-estradiol (and synthetic analog 17α-ethinyl estradiol) and estriol. Their ubiquitous presence in ecosystems poses a serious threat to wildlife and humans. Conventional wastewater treatment plants often fail to remove environmental estrogens (EEs). This review aims to focus attention on the urgent need to limit the presence of EEs in the environment through a modern and sustainable approach based on the use of recycled biowaste. Materials such as BC, HC and DG, the last being examined here for the first time as a biosorbent, appear appropriate for the removal of EEs both for their negligible cost and continuously improving performance and because their production contributes to solving other emergencies, such as virtuous management of organic waste, carbon sequestration, bioenergy production and implementation of the circular economy. Characterization of biosorbents, qualitative and quantitative aspects of the adsorption/desorption process and data modeling are examined.
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Abeysinghe, D. H., A. Shanableh, and B. Rigden. "Biofilters for water reuse in aquaculture." Water Science and Technology 34, no. 11 (December 1, 1996): 253–60. http://dx.doi.org/10.2166/wst.1996.0287.
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Aquaculture is a rapidly expanding industry in Australia and around the world. The majority of aquaculture operations employ flow through systems whereby residual feed and metabolic products are discharged to a nearby water body. In many countries, the discharge of nutrients rich aquaculture waters has contributed to the degradation of water quality in receiving water bodies. Aquaculture's dependency on water resources ultimately makes water recycling an attractive waste management option. Submerged flow biofilters, utilising a filter media with specific surface area of approximately 141m2/m3, were used to remove nitrogen and phosphorus from a synthetic fish farm water. Three biofilter systems were tested for nitrification, nitrification followed by denitrification, and combined nutrients removal. Successful carbon removal and nitrification were achieved in the nitrification system. The nitrification/denitrification biofilters achieved complete denitrification and nitrogen removal. The cyclic aerated/unaerated combined nutrients removal system achieved approximately 40 percent phosphorus removal, complete nitrification and 40 percent denitrification. The study demonstrated the viability of using biofilters for nutrients removal from fish farm waters. Biofilters are readily designed and constructed in modular form which makes such systems particularly useful for water quality management in aquaculture.
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Abdallah, Elsadig A. M., and Graham A. Gagnon. "Arsenic removal from groundwater through iron oxyhydroxide coated waste productsA paper submitted to the Journal of Environmental Engineering and Science." Canadian Journal of Civil Engineering 36, no. 5 (May 2009): 881–88. http://dx.doi.org/10.1139/s08-059.
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The goal of this research was to remove arsenic from groundwater supplies via adsorption into media obtained from waste material generated as by-products from glass recycling programs and the seafood industry such as crushed glass and scallop shells. During the course of this research four new adsorbents were developed: ferric hydroxide coated crushed glass (FHCCG); ferric oxide coated crushed glass (FOCCG); ferric hydroxide coated scallop shells (FHCSS); and ferric oxide coated scallop shells (FOCSS). The adsorbents were characterized through evaluation of their structure, surface area, chemical composition, iron content, and coating stability. Efficiency of the adsorbents to remove arsenic from water was examined through batch kinetic and isotherm adsorption experiments. The adsorption capacity of the adsorbents was also evaluated by performing column experiments using real ground waters and a synthetic water. Arsenic removal to a concentration less than 10 μg/L was achieved with the FHCSS and more than 9000 bed volumes of water were treated before the breakthrough point was reached. The research results revealed that scallop shells coated with ferric hydroxideperformed better than crushed glass coated with ferric hydroxide. Both FOCCG and FOCSS had poor arsenic removal compared with FHCSS and granular ferric hydroxide (GFH). Ferric hydroxide coated scallop shells performed similarly to GFH.
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Das, Somnath, and Dipankar Ghosh. "Potential of lignocellulolytic biocatalysts of native and proposed genetically engineered microbial cell factories on jute fiber modification and jute waste recycling: A review." Journal of Experimental Biology and Agricultural Sciences 10, no. 5 (October 31, 2022): 932–52. http://dx.doi.org/10.18006/2022.10(5).932.952.
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The lignocellulolytic microbial systems from different parts of the world responsible for lignocellulosic biomass (LCB) like jute (Corchorus spp.) waste degradation, fiber modification, and bioenergy production are not limited to a specific prokaryotic or eukaryotic group. The industrial applications of these highly efficient bacterial, fungal and algal communities are related to the production of lignocellulolytic enzymes such as cellulase, hemicellulase, lignin-peroxidase, versatile peroxidase, laccase, thermostable oxidants, pectinase, etc. They are a blessing for the jute, dye, paper, pulp, and biofuel industries as they help to generate a sustainable ecosystem. The jute plant is lignocellulosic biomass so it can be utilized in various ways, from everyday goods to power generation. Jute industries generally use different physicochemical strategies to generate quality fiber and post-retting activities, but these approaches cannot produce desired products; hence microbial routes are best for quality fiber generation, waste remediation, and biofuel generation. To this end, this review summarizes the most important milestones of the development of the leading enzyme-producing cell factories and their engineering by genetic, metabolic, and synthetic biology approaches with the emergence of high throughput methods, such as site-directed mutagenesis and others that can analyze the relevant mutations to accelerate our understanding of lignocellulolytic enzymology.
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Балыхин, Михаил Григорьевич, Изабелла Сергеевна Тверитникова, Ирина Анатольевна Кирш, Ольга Анатольевна Банникова, Ольга Владимировна Безнаева, Марина Ивановна Губанова, Юлия Александровна Филинская, Тамара Александровна Кондратова, and Михаил Павлович Щетинин. "Biodegradable polymer materials based on polyethylene and starch, modified with non-ionic surfactant." Food processing industry, no. 10 (September 30, 2021): 64–68. http://dx.doi.org/10.52653/ppi.2021.10.10.015.
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С каждым годом упаковки производится все больше и больше. В настоящее время все больше актуализируется проблема утилизации полимерных отходов. Одним из перспективных направлений в области утилизации упаковки является создание биоразлагаемых полимерных материалов. Главное их преимущество - это возможность использования в качестве наполнителей сырья постоянно воспроизводимых в природе веществ, сельскохозяйственных продуктов и отходов их производства, содержащих крахмалы, в отличие от нефти, угля и газа, имеющих ограниченный запас в природе. Анализ рынка биоразлагаемых полимерных материалов показал, что сегодня наибольший спрос имеет сегмент так называемых «дешевых» композиций. Поэтому целью работы является создание биодеградируемых полимерных композиций на основе синтетического полимера и природных материалов. В качестве объектов были выбраны синтетический материал - полиэтилен, природные вещества - кукурузный и картофельный крахмал, а в качестве модификатора неионогенное поверхностно-активное вещество, являющееся инициатором биоразложения. В работе были проведены исследования на реологические свойства и деформационно-прочностные характеристики, на способность исследуемых композиций к набуханию и биодеградации. В ходе работы были получены полимерные композиции, модифицированные природным материалом в количестве 20 % и 30 %, а также композиции с введением крахмала 20 % и 30 % с содержанием 2 % неионогенного поверхностно-активного вещества. Проведя исследования, можно отметить, что введение неионогенного поверхностно-активного вещества в крахмалонаполненные полимерные композиции улучшает реологические характеристики и повышает их прочностные характеристики; полученные модифицированные крахмалонаполненные композиции обладают повышенной биоразлагаемостью по сравнению с контрольными образцами. Every year more and more packaging is produced. Currently, the problem of recycling polymer waste is becoming more and more urgent. One of the promising directions in the field of packaging recycling is the creation of biodegradable polymeric materials. The main advantage of using biodegradable polymer compositions is the ability to use as fillers, raw materials constantly reproduced in nature, substances, agricultural products and waste products containing starches, in contrast to oil, coal and gas, which have a limited supply in nature. Analysis of the market for biodegradable polymer materials showed that today the segment of so-called «cheap» compositions is in greatest demand. Therefore, the aim of this work is to create biodegradable polymer compositions based on synthetic polymer and natural materials. The objects were selected: a synthetic material - polyethylene, natural substances - corn and potato starch, and as a modifier a nonionic surfactant that initiates biodegradation. In this work, the following studies were carried out on rheological properties and deformation-strength characteristics, on the ability of the studied compositions to swell and biodegradation. In the course of the work, polymer compositions were obtained modified with natural material in an amount of 20 % and 30 %, as well as compositions with the introduction of starch 20 % and 30 % with a content of 2 % nonionic surfactant. After conducting research, it can be noted that when a nonionic surfactant is introduced into starch-filled polymer compositions, it improves rheological characteristics and increases their strength characteristics; the obtained modified starch-filled compositions have increased biodegradability in comparison with the control samples.
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Myllymäki, Pekka, Janne Pesonen, Henrik Romar, Tao Hu, Pekka Tynjälä, and Ulla Lassi. "The Use of Ca- and Mg-Rich Fly Ash as a Chemical Precipitant in the Simultaneous Removal of Nitrogen and Phosphorus—Recycling and Reuse." Recycling 4, no. 2 (March 30, 2019): 14. http://dx.doi.org/10.3390/recycling4020014.
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The European Union’s circular economy strategy aims to increase the recycling and re-use of products and waste materials. According to the strategy, the use of industry waste material should be more effective. A chemical precipitation method to simultaneously remove phosphorus and nitrogen from synthetic (NH4)2HPO4 solution and the liquid phase of anaerobic digestate using fly ash as a precipitant was tested. Fly ash is a waste material formed in the power plant process. It mainly contains calcium oxide (CaO) and magnesium oxide (MgO). Saturated precipitant solution was prepared from fly ash, which was added in small proportions to (NH4)2HPO4 solution during the experiment. Fly ash’s effectiveness as a precipitant was compared with that of commercial CaO and MgO salts, and it can be observed that fly ash removed as much ammonium and phosphate as commercial salts. Fly ash sufficiently removed ammonium nitrogen and phosphate from the liquid phase of anaerobic digestate, which led to the formation of ammonium magnesium hydrogen phosphate hydrate, struvite (NH4MgPO4·6H2O), and calcium hydroxide phosphate, monetite, CaPO3(OH). In this study, we have shown for the first time that fly ash can be used to manufacture recycled, slow-release fertilizers from anaerobic digestate.
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Trably, E., D. Patureau, and J. P. Delgenes. "Enhancement of polycyclic aromatic hydrocarbons removal during anaerobic treatment of urban sludge." Water Science and Technology 48, no. 4 (August 1, 2003): 53–60. http://dx.doi.org/10.2166/wst.2003.0220.
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Anaerobically stabilized sewage sludge has potential to partially substitute synthetic fertilizers. The main risk with the recycling of urban sludge on agricultural soils is the accumulation of unwanted products, such as trace metals and organic micropollutants. In this context, the polycyclic aromatic hydrocarbons (PAHs) are particularly monitored because of their toxic properties at low concentrations and their high resistance to biological degradation. The aim of the present study was to optimize PAHs removal during anaerobic digestion of contaminated sewage sludge. Thirteen PAHs were monitored in laboratory-scale anaerobic bioreactors under mesophilic (35°C) and thermophilic (55°C) methanogenic conditions. Abiotic losses were statistically significant for the lightest PAHs, such as fluorene, phenanthrene and anthracene. It was shown that PAH removal was due to a specific biological activity. Biological PAHs removal was significantly enhanced by an increase of the temperature from 35°C to 55°C, especially for the heaviest PAHs. Bioaugmentation experiment was also performed by addition of a PAH-adapted bacterial consortium to a non-acclimated reactor. Significant enhancement of PAHs removal was observed. It was finally shown that PAH removal efficiencies and methanogenic performances were closely linked. The rate of biogas production may be used as an indicator of bacterial activity on PAH removal.
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Marcelino-Perez, Edgar, Marilés Bonet-Aracil, Eva Bou-Belda, Ana Amat Payá, Antonio Arques Sanz, and Rafael Vicente. "Polyamide 6.6 Degradation through Photo-Fenton Process." Materials Science Forum 1063 (June 10, 2022): 243–52. http://dx.doi.org/10.4028/p-28e9b7.
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Synthetic polymers have become essential in our life, nevertheless, the high production and the low recycling around the world have caused serious problems of contamination in soil and water. In addition, its fragmentation into microplastics in environmental conditions has exacerbated the ecological problems due to its possible ingestion by organisms and its high capacity to transport and release a wide variety of organic pollutants. Photo-Fenton process was used to evaluated its capacity to degrade PA6.6 microplastic under simulated solar irradiation and natural solar irradiation plus LED visible light in order to get a best knowledge about its behavior in environmental conditions. PA6.6 was degraded for 7 h through photo-Fenton process under simulated solar irradiation. Superficial defects were observed along the PA6.6 microplastic after degradation experiments. However, FT-IR analysis did not show the formation of additional bands which indicated the formation of new products. DSC analysis showed changes in the melting point of the PA6.6 after the photo-Fenton treatment at different times. The assays carried out under natural solar irradiation showed lower degradation of the PA6.6 under the same experimental conditions, nevertheless, it was observed an increase of the specific surface area 90 times higher in the PA6.6 treated for 10 h.
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Perera, K. I. D. P., D. G. Edirisinghe, and Laleen Karunanayake. "Characterization of Blends of Virgin Nitrile Rubber and Compounded Nitrile Rubber Latex Waste Reclaimed with Urea: Part II - Physico-Mechanical Properties." Journal of Advanced Chemical Sciences 7, no. 3 (June 25, 2021): 733–37. http://dx.doi.org/10.30799/jacs.238.21070301.
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Recycling of rubber waste materials in order to convert these to usable products is one of the main challenges in the rubber industry. Reclaiming of rubber waste and blending it with virgin rubber have increased during the past due to the growing concern on the environment and increase in the prices of synthetic rubbers. Hence, the aim of this study is to partially replace virgin nitrile rubber (NBR) with reclaimed compounded NBR latex waste to develop new rubber blends suitable for special applications. In this study, physico-mechanical properties, ageing performance and swelling behaviour of virgin NBR / reclaimed NBR blend vulcanizates were evaluated and compared with those of the control vulcanizate produced solely with virgin NBR. Results showed that replacement of 50% virgin NBR with reclaimed NBR retained 71-86% of tensile strength, elongation at break and resilience. Hardness and modulus of this blend vulcanizate increased by less than 18%, whereas abrasion volume loss and compression set increased by 27%. Ageing resistance is similar to that of the control vulcanizate. Interestingly, resistance to swelling in toluene and ASTM oil No.3 increased by 14% and 32%, respectively. Hence, the 50:50 virgin NBR / reclaimed NBR vulcanizate would be suitable for oil resistant applications.
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Stepp, J. David, Kristen Huang, and Sandra K. Lemmon. "The Yeast Adaptor Protein Complex, AP-3, Is Essential for the Efficient Delivery of Alkaline Phosphatase by the Alternate Pathway to the Vacuole." Journal of Cell Biology 139, no. 7 (December 29, 1997): 1761–74. http://dx.doi.org/10.1083/jcb.139.7.1761.
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A novel clathrin adaptor-like complex, adaptor protein (AP)-3, has recently been described in yeast and in animals. To gain insight into the role of yeast AP-3, a genetic strategy was devised to isolate gene products that are required in the absence of the AP-3 μ chain encoded by APM3. One gene identified by this synthetic lethal screen was VPS45. The Vps pathway defines the route that several proteins, including carboxypeptidase Y, take from the late Golgi to the vacuole. However, vacuolar alkaline phosphatase (ALP) is transported via an alternate, intracellular route. This suggested that the apm3-Δ vps45 synthetic phenotype could be caused by a block in both the alternate and the Vps pathways. Here we demonstrate that loss of function of the AP-3 complex results in slowed processing and missorting of ALP. ALP is no longer localized to the vacuole membrane by immunofluorescence, but is found in small punctate structures throughout the cell. This pattern is distinct from the Golgi marker Kex2p, which is unaffected in AP-3 mutants. We also show that in the apm3-Δ mutant some ALP is delivered to the vacuole by diversion into the Vps pathway. Class E vps mutants accumulate an exaggerated prevacuolar compartment containing membrane proteins on their way to the vacuole or destined for recycling to the Golgi. Surprisingly, in AP-3 class E vps double mutants these proteins reappear on the vacuole. We suggest that some AP-3–dependent cargo proteins that regulate late steps in Golgi to vacuole transport are diverted into the Vps pathway allowing completion of transfer to the vacuole in the class E vps mutant.
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Frank, Yulia, Alexandra Ershova, Svetlana Batasheva, Egor Vorobiev, Svetlana Rakhmatullina, Danil Vorobiev, and Rawil Fakhrullin. "Microplastics in Freshwater: A Focus on the Russian Inland Waters." Water 14, no. 23 (December 1, 2022): 3909. http://dx.doi.org/10.3390/w14233909.
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The low production costs and useful properties of synthetic polymers have led to their ubiquitous use, from food packaging and household products to high-tech applications in medicine and electronics. Incomplete recycling of plastic materials results in an accumulation of plastic waste, which slowly degrades to produce tiny plastic particles, commonly known as “microplastics” (MPs). MPs can enter water bodies, but only recently the problem of MP pollution of sea and fresh waters has become clearly evident and received considerable attention. This paper critically reviews the accumulated data about the distribution of MPs in the freshwater ecosystems of Russia. The available data on MP abundance in the lakes and river systems of the Russian Federation are analyzed (including the large Lakes Baikal, Ladoga, Onego, Imandra and Teletskoe, and the Volga, Northern Dvina, Ob, and Yenisei Rivers within their tributaries) and compared with the data on freshwater MP contents in other countries. In Russia, the main sources of MP pollution for rivers and lakes are domestic wastewater, containing microfibers of synthetic textiles, fishing tackle, and plastic waste left on shores. Among the MPs detected in the surface waters and bottom sediments, polyethylene (PE), polypropylene (PP), and polyethylene terephthalate (PET) particles predominate. The most common types of MPs in the surface freshwaters are fibers and fragments, with fibers prevailing in the bottom sediments. The reported average MP concentrations in the waters range from 0.007 items/m3 at the mouth of the Northern Dvina River to 11,000 items/m3 in the Altai lakes. However, the estimates obtained in different studies must be compared with great precaution because of significant differences in the methods used for MP quantification. The approaches to further improve the relevance of research into MP pollution of fresh waters are suggested.
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Oussai, Alaeddine, Zoltán Bártfai, László Kátai, and István Szalkai. "Development of a small-scale plastic recycling technology and a special filament product for 3D printing." International Journal of Engineering and Management Sciences 4, no. 1 (March 3, 2019): 365–71. http://dx.doi.org/10.21791/ijems.2019.1.45.
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In our days, the fight against pollution has become a real challenge for the state. recycling is one of the solutions that is adopted in several nations to reduce the rate of plastic discarded in nature. The amount of plastic waste has been increasing for decades contributing to the environmental pollution that is one of the most serious problem of the mankind. according to the statistics not only the household plastic waste, but the industry discharge is increasing because the utilization of plastic as a raw material is more and more extending. plastic can be found in a lot of products, huge number of bottles, plastic bags, computers, auto parts are sold every day. The current applications for using recycled plastics in fabrication and design are fairly limited, on a small scale, plastics (such as abs, HDPe1, or Pe2t) are shredded and formed into pellets, and then either extruded into lament to be used in existing 3d printers, or injection molded into small parts and pieces of larger components. at a large scale, recycled HDpE is melted into sheets and either used directly as sheets in construction, or then heat formed from a sheet into components for construction. these methods of fabrication using recycled plastics are the norm because of their straightforward processes. nevertheless, each method leaves some complexity to be desired. This paper we study the types of plastics and diagnose the pollution caused by the latter. this allowed us to design and size a recycling station of plastic into filaments for three-dimensional printers. this station which will contribute to the fight against pollution. the station consists of two machines for grinding of the plastic and the other for the extrusion of the desired filaments. we were able to make a theoretical academic study on both machines and also we designed with solidworks 2015. The theoretical study is spread of the mechanical calculations necessary to the design and validation of the structure using the tools. as the prospect of this project, we want to complete the achievement of this station while completing the crusher and extruder mechanically. then switch to electric and electronic parts (introduction of engines, sensors and wiring...). In the case of waste plastics that are recyclable and reusable. the most widely used are polyethylene terephthalate (pet, used for synthetic fibers and water bottles), and second high-density polyethylene (hdpe, used for jugs, bottle caps, water pipes).
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Uysal, Serkan, Eva Bou-Belda, Marilés Bonet-Aracil, and Jaime Gisbert-Payá. "Pre, Post and Meta Mordanting Recycled Cotton with Chitosan." Materials Science Forum 1063 (June 10, 2022): 189–94. http://dx.doi.org/10.4028/p-p698nx.
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The textile processing industry has imposed strict ecological and economic restrictions on the chemicals used, including bans on certain consumer goods containing synthetic agents which are posing challenges to sustainability issues [1, 2]. The worldwide demand for the use of environmentally friendly products in the textile industry is nowadays of great interest, possibly because of increasing concern about the environment, ecology, and pollution control [3, 4].It is a fact that the textile industry has grown many times during the last decades to meet global and domestic demand. This tremendous growth has also led to a parallel growth in environmental problems, which remained unnoticed. Any industrial activity produces pollution in one form or the other, and the textile industry certainly released a wide spectrum of pollution into the environment.The textile manufacturing process is characterized by the high consumption of resources such as water, fuel and a variety of chemicals in a long process sequence which generates a significant amount of waste. The common practices of low process efficiency result in substantial wastage of resources and severe damage to the environment [5, 6].Recycling implies the breakdown of a thing into its unrefined materials with the end goal that the rough material can be recuperated and used as a piece of new items. On the other hand, recycle insinuates a present thing being used again inside a comparable creation chain. Textile material recycling is the strategy by which old pieces of clothing and diverse materials are recovered for recycle or material recovery. It is the explanation behind the material recycling industry. Material recycling may incorporate recouping pre-consumer waste or post-consumer misuse. There are different ways to deal with perceive the sorts of recycling possible inside the material [7].Pre-consumer waste is a material that was disposed of before it was prepared for customer utilize. Pre-consumer recycled materials can be separated and revamped into comparative or diverse materials or can be sold as such to outsider purchasers who at that point utilize those materials for buyer items. Pre-consumer material waste for the most part alludes to squander results from fiber, yarn, material, and clothing fabricating. It can be process closes, scraps, clippings, or merchandise harmed amid creation, and most is recovered and recycled as crude materials for the car, furniture, sleeping cushion, coarse yarn, home outfitting, paper, and different ventures. Pre-consumer squanders are produced all through the first phases of the inventory network. In the crude materials area (fiber and yarn creation), ginning squanders, opening squanders, checking squanders, comber noils, brushed waste yarns, meandering squanders, ring turning waste fibers, ring-spun squander yarns, open-end spinning waste fibers, and open-end spinning yarn squanders are usually gathered for recycling [8].The ground root of the madder plant, Rubia Tinctorum L., formerly cultivated in many parts of Europe and North and South of America. Was largely used for dyeing Turkey Red on cotton mordant with alum in presence of lime. Applied to wool on an alum- or chrome-cream of tartar mordent [9].Natural dyes with a few expectations are non-substantive and hence must be used in conjunction with mordants. Mordant is a chemical, which can fix itself on the fiber and combines with the dyestuff. The challenge before the natural dyers in application of natural colour is the necessity to us metallic mordants which themselves are pollutant and harmful. Due to the environmental hazard caused by metallic mordant while dyeing of textile fabric, dyers are always looking for safe natural mordant for natural dyes [10].The applications of chitosan for different applications in textiles are reported [11–12], but the application of such functional biopolymer as a mordant in natural dyeing has been quite rare in the literature. In the current work, chitosan extracted from waste shrimp shells [12] was utilized as a mordant for simultaneous natural dye printing and antibacterial finishing of cotton in comparison with commonly used metal mordants. The efficacy of chitosan as eco-friendly mordant and antibacterial finish has been studied.The paper discusses a comparison between different ways to mordant cotton with chitosan. This research as a first step of further experimental, provide us the optimum values and applications for the future research. As a result, we could conclude the mordanting process was more effective from the point of view of dyeing yield.