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In this investigation, we used a circular economy approach by recycling metal scrap from industry as a component in creating nanoparticles. For producing iron oxide NPs we used electrochemical method with scrapped rusted iron nails as electrodes. In this technique, we used 50mM ferrous sulphate solution as an electrolyte and a direct current power supply. Different methods were used to characterise the synthesised iron oxide NPs, including ultraviolet-visible (UV-visible) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), and transmission electron microscopy (TEM). The results demonstrated that the synthesised iron oxide NPs have an average crystallite size of 7.54 nm. Iron oxide NPs has potential to adsorb Congo red dye hence prepared NPs have been utilised for the adsorption of Congo red dye. [ABSTRACT FROM AUTHOR]

Kiln dust material is collected during the manufacturing process of cement industry. It is considered as a waste material and poses environmental pollution. The properties of Kiln dust material depend on the kind of raw materials and fuel used. It is considered as a waste material This study focuses on the utilization the waste materials for ceramic products (bricks and tiles). The efficiency parameters (percentage of raw materials, additives, and firing temperature) during manufacture of the samples. Different amount of Kiln dust materials (20, 30 and 40) % were mixed with red kaolin clay and 10% (Na2CO3) is added to reduce firing temperature as a catalyst to prepare glassy phase. The samples were prepared by semi-dry press at a pressure 250 Kg/cm2 in two molds, cylinder (3.5 × 10 cm2) and square (5 × 5 cm2) for brick and tile respectively. Theses samples were dried at room temperature for 48 h. and at 110 °C for 24 hr. then, fired in muffle furnace at different firing temperatures (1050, 1100 and 1150 °C). The properties of ceramic materials after firing are produced a new material modifying in properties, and it is desirable stability of the product during the manufacture, as well as, firing temperature of the samples are very influential parameter on the physical and mechanical properties. Using kiln dust material with red kaolin clay, needs to high firing temperature up to 1150 °C, but the presence Na2CaCO3 in sample aid to decrease firing temperature to 1100 °C, with maintain requirement [1, 2, 3], fixing the addition of kiln dust material should not exceed 30%.

Due to the environmental issues associated with the production of binders such as cement and lime, finding alternative materials or binders for geotechnical applications is crucial. Therefore, developing low-carbon-footprint cementitious materials by replacing cement and lime with recycled waste-based geopolymers can provide environmental and economic benefits. Incorporating recycled waste materials or green binders in soil stabilizations can not only reduce the construction cost and alleviate environmental issues, but also improve the mechanical properties of the soils. Although the idea of using recycled glass powder (RGP) as a reclaimed material for stabilizing clay soils is not new, the adoption of copper slag (CS) or combination of CS and RGP for the treatment of low-plasticity clay soil has rarely been studied. In this research, various molarities of sodium hydroxide as an alkaline activator and different combinations of CS-RGP were used to assess the mechanical and microstructural behavior of the stabilized low-plasticity clay soil. Moreover, the effects of two different curing conditions (i.e., oven-dried content (DC) and optimum water content (OC)) and curing time on the mechanical properties of the soil (i.e., unconfined compressive strength and California bearing ratio) were evaluated. The results clearly indicated that CS influenced Atterberg Limits and compaction parameters more than RGP. Also, it was observed that by applying 5% CS at a fixed alkaline activator, the UCS at 56 curing days and CBR at 7 curing days increased 3.11 and 1.68 times, respectively, while these values were 4.03 and 1.90 times, respectively, by applying 5% RGP.

Reclaimed asphalt pavement (RAP) contributes substantially to the volume of recycled waste in the world. This research aims to evaluate the mechanistic performance of asphalt concrete with 100% RAP (RAP-AC) modified with natural hemp fiber (HF) reinforcement. The effects of HF lengths and HF contents on the mechanistic performance were investigated. The static tests included Marshall stability, strength index (SI), and indirect tensile strength (ITS), whilst the cyclic tests included indirect tensile resilient modulus (IT Mr), indirect tensile fatigue life (ITFL), and rutting resistance tests. The microstructural analysis revealed that HF could absorb more asphalt cement and function as a reinforcement. The 0.05% HF with a 24 mm HF length was suggested as the best ingredient. For various stress levels, the higher resilience properties—due to the addition of HF—contribute to higher levels of ITFL and rutting resistance. Based on a critical analysis of the cyclic test data, the distress model for HF-RAP-AC was developed for mechanistic pavement design. The outcome of this research promotes the usage of HF-RAP-AC as a greener material for low-traffic roads, which account for over 70% of the total roads worldwide. [ABSTRACT FROM AUTHOR]

The introduction of large amounts of pharmaceuticals into the environmental waters is well‐documented in literature with their occurrence reported in all different water matrices accessible to humans and animals. At the same time, the increasing consumption of coffee and tea‐based beverages results in the generation of solid waste, which is mostly disposed‐off in the environment. To minimize environmental pollution, coffee and tea‐based materials have been proposed as suitable options to remove pharmaceuticals in environmental waters. Therefore, this article provides a critical review on the preparation and applications of coffee and tea‐based materials in removing pharmaceuticals from contaminated water. In this context, most studies in literature focused on the applications of these materials as adsorbents, while only limited work on their role in degradation of pharmaceuticals is discussed. The successful application in adsorption studies is attributed to high surface areas of adsorbents and the ability to easily modify the adsorbent surfaces by incorporating functional groups that provide additional oxygen atoms, which promote easy interactions with pharmaceuticals. Hence, the adsorption mechanisms are mostly described by hydrogen bonding, electrostatic and π–π interactions with sample pH playing a dominant role in the adsorption process. Overall, the present article focused on the developments, trends and future research direction on the preparations and applications of coffee and tea‐based materials for efficient removal of pharmaceuticals in water. Practitioner Points: Review of tea and coffee wastes application for removal of pharmaceuticals in waterKey applications in adsorption and degradation of pharmaceuticals in waterRemoval mostly explained by hydrogen bonding, electrostatic, and π–π interactionsTrends, gaps, and future research to be explored are reviewed and highlighted [ABSTRACT FROM AUTHOR]

Copyright of Roads & Bridges / Drogi i Mosty is the property of Road & Bridge Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Sustainability emphasises the importance of increasing the resource efficiency of infrastructure. The usage of geosynthetic materials in civil and environmental engineering can significantly influence sustainability at the planning and design stages of infrastructure construction projects. They are used in many different applications in construction and environmental engineering, as they provide a better and longer performance and less costly solutions than traditional materials (such as sand, gravel, concrete and cement). Additional benefits can be achieved by combining geosynthetics with various recycled materials as substitutes for high-quality natural materials. In this paper, the importance of sustainability in geosynthetics-based solutions is discussed. The possibilities of using geosynthetics in sustainable development have been analysed and the benefits resulting from their application, such as the reduction in carbon footprint and release of greenhouse gases and saving water and other natural resources, have been assessed. Innovative solutions that support mitigation measures, adaptation to climate change and achievement of sustainable development goals have been presented. [ABSTRACT FROM AUTHOR]

Arsenic is a metalloid whose presence can be due to natural or anthropological causes. It is considered as a toxic chemical that puts human health at high risk. In this study, we evaluated a novel modified oyster shell (MOS) that was coated with iron (II) sulfate heptahydrate using two different proportions through batch sorption experiments in an arsenic solution and in arsenic-contaminated soils. The arsenic solution was prepared using As(III)-standard solution. The arsenic contaminated soils were extracted from a contaminated site in Cheonan, South Korea, where the average arsenic concentration of the soil was reported as 136.28 mg/kg. Different doses of oyster shell and modified oyster were used to understand the effect of the addition of iron (II) sulfate heptahydrate via sorption batch experiments in solution and sorption tests in soils. The sorption tests were conducted with 50 g of contaminated soil; then, 150 g of soils was used for the pot cultivation tests, and finally, 150 g of contaminated soils was used for column percolation test. Through the experiments, the authors observed a comparable improvement of arsenic stabilization from 10 to 60% with the addition of iron (II) sulfate heptahydrate to oyster shell. [ABSTRACT FROM AUTHOR]

The current practices in the recent development of fired clay brick (FCB) by adopting waste materials have tremendously reduced the usage of the primary source of FCB, which is clay soil (CS). In this study, the main objective is to reduce the utilisation of CS as the main component in the FCBmaking process. Other waste materials such as soda lime silica (SLS) glass bottles, and sea shells (SS) were also added into the precursor admixtures. The admixtures containing CS, SLS and SS were mixed according to the empirical formula of (1-x)[40SLS - 60CS]: x[SS] = 0, 10, 20, 30, 40 wt.%. A batch of 40 g mixture was prepared, and 21% water was added. The admixtures were mixed, moulded into a rectangular brick shape, and dried before the sintering process at 850 °C. The physical properties of the FCB were investigated as a function of the SS content in the form of apparent density, linear shrinkage, loss of ignition and plasticity. As a result, the apparent density and loss of ignition of the FCB increased from 1.91 gcm-3 to 2.31 gcm-3 and 10.60 % to 20.81%, respectively. The linear shrinkage and plasticity percentage decreased from 2.50% to 2.27% and 11.01% to 8.70% with an increase of SS content. This study has uncovered the above findings, and has demonstrated a promising discovery of the SS as a possible substitute in FCB. [ABSTRACT FROM AUTHOR]

The use of ashes derived from various waste sources as supplements to synthesized ceramic reinforcement in metal matrices has been established. However, studies involving a combination of particulates from three different sources are rare. In a bid to further knowledge in this aspect of research and develop a green aluminium composite for automobile applications, the present investigation studied the implication of adding palm kernel shell ash (PKA), rice husk ash (RHA), and waste steel particles (STP) to the morphology and strength behaviour of Al-6061-T6 alloy. The experimental design was undertaken via the Box–Behnken design (BBD) of the response surface method. A 4% STP at a constant dose was mixed with PKA and RHA at varying proportions and stirring temperatures according to the BBD. The experimental outcome revealed that the responses were greatly influenced by microstructural evolution. From the surface plots, 2–4% RHA and PKA enhanced tensile and flexural strengths, while 4–6% led to a decline in strength. Meanwhile, 2–6% of the particles are favourable to the enhancement of tensile and compressive strengths and moduli. Temperatures between 700 and 800 °C favored response improvement, whereas temperatures between 800 and 900 °C were detrimental to responses. Developed regression models for the responses were validated to be good representations of the experimental outcomes. The optimum mix was obtained at 4.81% PKA, 5.41% RHA, and a stirring temperature of 803 °C. The validation experiment conducted portrayed reliable responses with <5% deviation from the predicted values, thereby certifying the models to be statistically fit for future predictions. [ABSTRACT FROM AUTHOR]

The topical challenge for the Polish, European, and global fertilizer industry is to produce sufficient nutrients for growing plants using more energy-efficient and environmentally friendly methods. The appropriate course of action, in terms of the challenges posed, could be the production of liquid fertilizers, made from waste materials that exhibit fertilizer properties. This solution makes it possible not only to reduce the exploitation of natural resources but above all, to implement elements of a circular economy and reduce the energy intensity of the fertilizer industry. This study shows that both in Poland and the European Union, there are current regulations aimed at elements of a circular economy and indicating the need to obtain fertilizers containing valuable plant nutrients from organic waste or recycled materials. The recognition carried out for the Polish market clearly indicates that to produce liquid organic fertilizers and soil conditioners, the most used is the digestate from the fermentation process. The preparation of liquid organic–mineral fertilizers is mainly based on algae extracts. Mine minerals are used in the production of mineral–liquid fertilizers. An analysis of data has shown that the above-mentioned waste materials, used as substrates to produce fertilizers, contain chemical substances and elements important for, among other things, stimulation of proper plant development, growth of aboveground and underground parts of plants, increased resistance to diseases and pests, and regulation of plant water management. Referring to the above information, the production of liquid fertilizers from waste materials seems reasonable and is an alternative to mineral–solid fertilizers, whose production process is energy-intensive and produces air emissions. Detailed identification of the properties of the various components made it possible to demonstrate their usefulness in terms of fertilizing plants and soils, but also to emphasize the importance of this line of research and the need to look for other groups of waste for reuse within the framework of a circular economy. [ABSTRACT FROM AUTHOR]

In this study, a combination of geopolymers including Rafsanjan Natural Pozzolan (RNP), Cement Kiln Dust (CKD), and an activator such as Calcium Carbide Residue (CCR) or NaOH was used to stabilize and improve the poorly graded sandy soil. Factors such as the activator type, activator concentration, CKD and RNP content were studied. Chemical compounds of the soil and abovementioned materials were investigated using X-ray Diffraction (XRD) and X-ray Fluorescence (XRF) detection tests. Unconfined Compressive Strength (UCS) tests were carried out to evaluate the mechanical behavior of the specimens. The findings revealed that CKD, which is a hazardous byproduct, could be turned into an eco-friendly construction material through geopolymerization. The presence of CKD along with NaOH significantly increased the UCS of the samples compared to unstabilized specimens (control 1). Microstructural analyses using Scanning Electron Microscopy (SEM) confirmed the desirable distribution of the geopolymer gel in the stabilized soil. According to the SEM images, it was observed that the samples stabilized with CKD had a higher strength than those stabilized with CKD combined with RNP due to the formation of a greater amount of gel and a stable microstructure. The findings of this research promote sustainable ground improvement techniques using waste by-products. [ABSTRACT FROM AUTHOR]

As a result of exorbitant electricity bills, high cost of obtaining liquefied petroleum gas (LPG), and kerosene or paraffin oil, it has become necessary to develop a modular briquette stove as an alternative source of heating food in rural and urban households, restaurants and other business operations and facilities. This study is aimed at the construction of a modular cookstove for small and medium scale use, electricity generation, the designed stove is specifically developed to be fueled by briquettes produced from water hyacinth (WH). Improvement has been made in the development of the biomass stove to counter previous designs and specifically address the problem of pollution. The major improvements of the biomass stove design are the following: The provision of insulation around the combustion chamber to reduce heat loss through the walls of the chamber; incorporation of smoke rings on the top surface of the stove; provision of adjustable and variable air intake to ensure adequate air for complete combustion of hyacinth briquettes. The performance of the developed stove was evaluated and the results showed that the WH briquette stove has an average thermal efficiency of 70.51%. This indicates a better performance compared to the average thermal efficiency value reported in the literature. The briquette stove is designed with a standard chimney to transport carbon and reduce smoking. In conclusion, the commercial production of the developed product in volume will generate a stream of income and also help to engage young people. [ABSTRACT FROM AUTHOR]

Triboelectric Nanogenerators (TENG) is a promising approach for clean energy harvesting. Light weight, flexible, cheap and environmentally-friendly materials are being explored as potential components in the TENG device in order to increase its efficiency. This paper reports the first effort to successfully utilize rebonded flexible polyurethane (RFPU) waste as a tribopositive material in a TENG device. A batch moulding technique was used to create two different densities (60 and 70 kg/m3) of flexible polyurethane (FPU) scraps, including customer waste and slabstock foam production waste. The current study investigates the effect of density on the compression strengths of the RFPU materials, as well as the impact on the output voltage of the TENG. Additionally, the effect of various RFPU sheet thicknesses (2, 4, 6, and 8 mm) as well as the effect of different applied forces and frequencies on the TENG's output voltage were investigated. The findings showed that the compressive strength increases with higher RFPU density. The output voltage values of the TENG device were recorded both with and without pre-charging. The results, without pre-charging, revealed that the highest output voltage of the TENG was obtained using an RFPU sheet with a density of 60 kg/m3. Furthermore, output voltage was shown to decrease with increasing RFPU sheet thickness and to increase with applied frequency. Pre-charging showed a similar trend, but yielded better results compared to the RFPU samples that were not pre-charged. The power density peaked at 0.085 mW/cm2, at a load resistance of 5 MΩ and a force of 4.7 N. The RFPU-based TENG successfully powered four white LEDs connected in series. Analysis of the embodied energy associated with using PU foam waste instead of virgin PU foam was conducted and demonstrated that utilizing PU foam waste provides environmental benefits due to the significant contribution of raw materials to the overall embodied energy in PU foam that is saved when reusing foam waste. Additionally, assessing the embodied energy of the components of the TENG device was also conducted and shows that the generated energy can partially offset the embodied energy of the TENG device. As a result, the prepared RFPU material not only helps to safeguard the environment but also shows great promise for use in developing more efficient and affordable TENGs in the future. [Display omitted] • This study reports the first attempt to use rebonded FPU scrap as a tribopositive layer in a TENG device. • Increasing the density and thickness of RFPU led to a decrease in the output voltage • Increasing the applied force and operating frequency increased the output voltage • The maximum power density of the RFPU-based TENG was 0.085 mW/cm2. • The developed TENG device successfully turned on four white commercial LEDs and charged a 10 μF capacitor to 16 V in 25 s. [ABSTRACT FROM AUTHOR]

Waste materials may be used as raw materials for interlocking masonry products in order to contribute to sustainable development and environmental protection. Rubberized concrete Interlocking Brick (RCIB) was developed by volumetric replacement of 56% of the ordinary Portland cement with fly ash and 20% of the sand with crumb rubber (CR) to reduce the production cost of conventional concrete bricks (CCB) and restrict the depletion of natural resources and contributing to solving the environmental problems associated with the accumulation of scrap tires in landfills. The mechanical and sustainability evaluation of masonry prism made of the developed brick is the aim of this research. Consequently, compressive strength, failure mechanism, stress–strain behaviour, and energy absorption of grouted and ungrouted prisms made of RCIB were measured experimentally under axial compression load. The thermal resistance, fuel consumption, CO2 emission, and cost analysis of RCIBs were estimated. The findings reveal that grout had a significant impact on the compressive strength of rubberized concrete interlocking masonry prisms where the compressive strength of grouted and ungrouted prisms was 10.99 MPa and 5.83 MPa, respectively. Web splitting and vertical cracks were the common failure modes observed in both prisms. Moreover, the rubberized concrete interlocking masonry prisms revealed greater energy absorption as well as a gradual and ductile failure mechanism. The RCIB exhibited higher thermal resistance than CCB (increased from 0.106 to 0.171 m2 K/W) which could contribute to a 62% reduction in annual fuel consumption and CO2 emission. Further, more than 25% of the material cost could be saved.

This paper explores the use of waste materials as substitutes in ceramic paste formulations. Building on previous research which has laid the groundwork for the use of volcanic ash as temper in ceramic tile manufacture, investigation is here extended to a broader spectrum of waste-based ceramic pastes. Specifically, five different mixtures have been manufactured through the hand-made technique by using Etna volcanic ash and/or tile processing residues (chamotte), mixed with clay in variable proportions. Physical-mechanical tests including flexural strength, water absorption, resistance to thermal shock, deep abrasion and impact, have been performed and results compared with those of reference tiles. Notably, ceramic pastes combining clay with chamotte or clay with chamotte and fine volcanic ash, show better performance. This is certainly due to the good physical-mechanical properties of chamotte which binds well with the clayey groundmass so reducing shrinkage / cracking and improving the overall quality of ceramic products. Conversely, volcanic ash does not show a high degree of union with the clayey matrix, particularly when occurring in larger grain size. However, when present in fine clasts and in combination with chamotte, the resulting products display good physical-mechanical characteristics. This study highlights once again the potential of waste materials in ceramic manufacturing, paving the way for a more sustainable and resource-efficient industry. • Etna volcanic ash and chamotte as substitute temper in ceramic paste formulations. • Waste materials for a more sustainable and resource-efficient ceramic industry. • Chamotte binds well to the clay matrix improving the quality of the ceramic body. • Pastes with chamotte or chamotte plus fine volcanic ash show better performance. • Coarse volcanic ash does not show a high degree of union with the clayey matrix. [ABSTRACT FROM AUTHOR]

The study underscores the urgent need for sustainable waste management by focusing on circular economy principles, government regulations, and public awareness to combat ecological threats, pollution, and climate change effects. It explores extracting nanocellulose from waste streams such as textile, paper, agricultural matter, wood, animal, and food waste, providing a detailed process framework. The emphasis is on waste-derived nanocellulose as a promising material for eco-friendly products. The research evaluates the primary mechanical and thermal properties of nanocellulose from various waste sources. For instance, cotton-derived nanocellulose has a modulus of 2.04–2.71 GPa, making it flexible for lightweight applications. Most waste-derived nanocelluloses have densities between 1550 and 1650 kg/m3, offering strong, lightweight packaging support while enhancing biodegradability and moisture control. Crystallinity influences material usage: high crystallinity is ideal for packaging (e.g., softwood, hardwood), while low crystallinity suits textiles (e.g., cotton, bamboo). Nanocelluloses exhibit excellent thermal stability above 200 °C, useful for flame-retardant coatings, insulation, and polymer reinforcement. The research provides a comprehensive guide for selecting nanocellulose materials, highlighting their potential across industries like packaging, biomedical, textiles, apparel, and electronics, promoting sustainable innovation and a more eco-conscious future. [ABSTRACT FROM AUTHOR]

With the development of science and technology, the power source of the automobile industry has gradually changed from non-renewable energy sources such as petroleum to electric energy, a clean and renewable energy source. By the end of 2020, scientists have found that the global demand for batteries has greatly increased. The demand for power batteries has reached 50% of all battery demand, occupying half of the market. In addition, scientists also boldly predict that by 2025, China's consumption of batteries in the automobile industry will reach more than 100,000 tons per year. Faced with so much battery consumption, how to dispose of and recycle LiFePO4 used batteries has become the key to restricting the development of the industry. Failure to dispose of used batteries will not only hinder the development of the industry, but also cause serious pollution to the environment. The application of sensors today has been extended to various fields, and the emergence of satellite navigation and positioning technology is one of the driving forces to promote its development. However, the sensor cannot be directly applied to various environments. When in a complex environment, the obstruction of various objects in the environment will seriously affect the stability of the sensor. In order to ensure the normal operation of the sensor, positioning technology began to be applied to the sensor. The industrial production process of solid-phase regeneration and electrochemical performance of waste lithium iron phosphate materials discussed in this article is based on this perspective, through the use of computer vision positioning to reduce the impact of environmental factors on the accuracy of the sensor, thereby improving the quality of the battery. In order to match the image point of the waste lithium iron phosphate material with the space point, this paper creatively uses the image point and the point in the corresponding space field. In addition, the author also studied the camera's rear rendezvous method and proposed a new rear rendezvous method. In addition, in order to strengthen the detection of waste lithium iron phosphate materials, this paper strengthened the construction of the sensor hardware system and software system, and completed the upgrade of the waste lithium iron phosphate material detection system.

The goal of this study is to develop a method of manufacturing porous ceramic skeletons used as semi-finished products for reinforcement of composite materials or as filters. For manufacturing skeletons, only waste materials from coal combustion (fly ashes and bottom slags) as well as rubber granules from used tires and car parts were used. These granules were a pore-forming agent that underwent thermal degradation during sintering process. The influence of sintering temperature, portion, and type of rubber granules on the porosity of developed ceramic skeletons was determined. The study of structure of base materials and the developed ceramic skeletons in a scanning electron microscope as well as their X-ray phase analysis were made. Results will allow to predict phases that can be formed on the metal-reinforcement interface during pressure infiltration.

In recent years, due to the reduction in available natural resources, the attention of many researchers has been focused on the reuse of recycled materials and industrial waste in common engineering applications. This paper discusses the feasibility of using seven different materials as alternative fillers instead of ordinary Portland cement (OPC) in road pavement base layers: namely rice husk ash (RHA), brick dust (BD), marble dust (MD), stone dust (SD), fly ash (FA), limestone dust (LD), and silica fume (SF). To exclusively evaluate the effect that selected fillers had on the mechanical performance of asphalt mixtures, we carried out Marshall, indirect tensile strength, moisture susceptibility, and Cantabro abrasion loss tests on specimens in which only the filler type and its percentage varied while keeping constant all the remaining design parameters. Experimental findings showed that all mixtures, except those prepared with 4% RHA or MD, met the requirements of Indian standards with respect to air voids, Marshall stability and quotient. LD and SF mixtures provided slightly better mechanical strength and durability than OPC ones, proving they can be successfully recycled as filler in asphalt mixtures. Furthermore, a Machine Learning methodology based on laboratory results was developed. A decision tree Categorical Boosting approach allowed the main mechanical properties of the investigated mixtures to be predicted on the basis of the main compositional variables, with a mean Pearson correlation and a mean coefficient of determination equal to 0.9724 and 0.9374, respectively. [ABSTRACT FROM AUTHOR]

The need for new non-animal and non-petroleum-based materials is strongly emphasized in the sustainable and green economy. Waste materials have proven a valuable resource in this regard. In fact, there have been quite a large number of goods obtained from wastes called "Vegan leather" that have gained the clothing market's attention in recent years. In practice, they are mostly composites of waste materials like cactus, pineapples, or, eventually, apples with polymers like polyurethane or polyvinyl chloride. The article presents the results of work aimed at obtaining a material based entirely on natural, biodegradable raw materials. Bacterial cellulose produced as a byproduct of the fermentation carried out by SCOBY was modified with glycerol and then altered by the entrapment of apple powder. The effect of introducing apple powder into the SCOBY culture media on the mechanical properties of the obtained bacterial cellulose was also evaluated The resulting material acquired new mechanical characteristics that are advantageous in terms of strength. Microscopic observation of the apple powder layer showed that the coverage was uniform. Different amounts of apple powder were used to cover the cellulose surface from 10 to 60%, and it was found that the variant with 40% of this powder was the most favorable in terms of mechanical strength. Also, the application of the created material as a card folder showed that it is durable in use and retains its functional characteristics for at least 1 month. The mechanical properties of modified bacterial cellulose were favorably affected by the entrapment of apple powder on its surface, and as a result, a novel material with functional characteristics was obtained. [ABSTRACT FROM AUTHOR]

Adsorption has been considered as a promising remediation technology to separate organic and inorganic agrochemicals from contaminated soil and water. Low-cost adsorbents, including waste derived materials, clay composites, biochar, and biochar modified materials, have attracted enormous attention for the removal of organic contaminants, including pesticides. In this study, iron-modified base-activated biochar (FeBBC) was prepared by pyrolysis (at 400 °C for 1 h) of iron-doped base (KOH) activated sugarcane bagasse for the removal of a widely used insecticide, namely imidacloprid (IMI) from water. The maximum adsorption capacity of the adsorbent (FeBBC) was calculated as 10.33 (± 1.57) mg/g from Langmuir isotherm model. The adsorbents could remove up to ~ 92% of IMI from aqueous solution at 23.8 mg/L IMI. Experimental data fitted well with the Freundlich model and pseudo-second-order model, demonstrating physisorption, as well as chemosorption, contributed to the sorption process. Even at highly acidic/basic solution pH, the FeBBC could remove substantial amount of IMI demonstrating hydrophobic interaction and pore diffusion play vital role for removal of IMI. The slight improving of IMI sorption with increasing solution pH indicated the sorption was also facilitated through ionic interaction alongside physical sorption. However, physical sorption including hydrophobic interaction and pore-filling interaction plays a vital role in the sorption of IMI. [ABSTRACT FROM AUTHOR]

The paper presented the possibility of manufacturing aggregates from industrial waste materials and their ecological benefits. The cold bonding process to create aggregates uses substantially less energy than the sintering technique. This study deals with the outcomes of an experimental assessment of the physical and strength properties of environment-friendly cold-bonded and sintered fly ash (FA), ground granulated blast furnace slag (GGBFS), and quartz (Q) lightweight aggregates. The waste materials were mixed with Portland cement at 20–50 percent by weight to make artificial lightweight aggregates. To investigate the impacts of temperature on the physical properties, such as crushing strength, density, and water absorption, the pellets were sintered at 300, 600, and 900 °C for an hour. The results show that all the produced aggregates might be categorized as lightweight aggregates due to the combinations' average densities being less than 2,000 kg/m³. The fly ash lightweight aggregates had higher density and crushing strength, as well as decreased water absorption. The density and crushing strength improved somewhat by raising the temperature, while the water absorption decreased with increased temperature. In this research, the most efficient mineral admixture concentration has been evaluated as 50 percent for both fly ash and ground granulated blast furnace slag and 30 percent for quartz for cold-bonded pellets. Furthermore, superior physical qualities have been reported at the 900 °C sintering temperature. [ABSTRACT FROM AUTHOR]

This study aims to examine the failure behaviour of damaged reinforced concrete (RC) beams retrofitted using externally bonded ultra-high-performance fibre-reinforced cementitious composites (UHPFRCCs) systems at different levels of damage levels. To overcome the sudden failure in shear at supports, one strip of UHPFRCCs was bonded on the tension face with four short strips on vertical sides covering the tension strip supports and ends of damaged RC beams. The results show that an increment in the average failure capacity over that of control beams was in the range of 24.37 to 38.39%. Moreover, the serviceability of RC beams showed a marked enhancement in failure mode, crack development and deflection capacity. 0.0% of the retrofitted beams failed in shear mode. It can be concluded that, the externally bonded UHPFRCCs technique can be used for improving the RC flexural members. [ABSTRACT FROM AUTHOR]

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Tekst i Dyskurs is the property of University of Warsaw and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Significant research investigations on the characteristics of unexplored clay deposits are being conducted in light of the growing need for clay in the ceramic industry and the variable chemistry of clays. Parallel to this, the generation of waste materials like fly ash, ferrochrome slag, and silica fume is also increasing, responsible for environmental degradation. This paper aims to study the mineralogical properties of pure clays (one specimen from Siberia and five specimens from different locations in Turkey), and the effect of mentioned waste materials on the index properties of clays obtained. This study is divided into two phases, wherein in the first phase, the pure clay specimens are analyzed against mineralogical properties (i.e., chemical composition, thermal analysis, and particle size distribution). While in the second phase, index properties of pure clay specimens and clay specimens modified with 0–50% fly ash, ferrochrome slag, and silica fume are analyzed. The results reveal that the clay specimens from Turkey (USCS classification: CL) are fit for the ceramic industry and bricks production, and incorporation of waste materials can further improve their index properties. It is also observed that incorporation of 10–30% fly ash and ferrochrome slag have higher efficiency in reducing the plasticity index of clays studied as compared to the addition of silica fume. [ABSTRACT FROM AUTHOR]

Trivalent erbium (Er3+)-embedded calcium silicate (Ca 2 SiO 4) phosphors have been prepared by using the agro-food trash resources, such as egg shells and rice husk, via high temperature solid-state reaction technique and studied their structure, morphology and spectroscopic properties. X-ray diffraction patterns revealed that Ca 2 SiO 4 phosphors are crystallized in monoclinic structure, while scanning electron microscopy (SEM) micrograph reflected that particles are agglomerated in different shapes and magnitudes with a non-uniform distribution. Luminescence spectra of Er3+-doped Ca 2 SiO 4 phosphors have been systematically investigated as a function of the Er3+ concentration under 488 and 980 nm laser excitations. Down shifting spectra exhibit characteristic emissions of Er3+ ions at around 524, 545 and 636 nm in the visible and at 1531 nm in the near-infrared regions. Non-exponential decay curves of the 4S 3/2 and 4I 13/2 emitting levels have been associated with decrease in lifetimes with increase in Er3+ ions concentration. Colour coordinates are shifted from the yellowish green to the green region with increase of Er3+ content. The phosphors also emit intense NIR-to-visible upconversion luminescence under 980 nm laser excitation. The above results indicate that the Ca 2 SiO 4 :Er3+ phosphor could find potential applications in the WLEDs and optoelectronic devices. [ABSTRACT FROM AUTHOR]

This work aims to study the relationship between the results of lightweight self compacting concrete (LWSCC) made with waste expanded polystyrene (EPS) beads to find an empirical equation to predict mechanical characteristics and compare their results with code empirical equations. The workability and hardened characteristics were examined for sustainable LWSCC which was produced with a water to binder ratio of 0.35 and substituted the normal coarse aggregate with different volume fractions of EPS beads at 0%, 40%, 50%, 60%, 70%, and 80%. All the mixes contain a binder content of 500 kg/m3. Slump flow diameter and time, as well as V-shape flow time, were used to determine the workability of LWSCCs. Additionally, hardened properties such as dry density, ultrasonic pulse velocity (UPV), water absorption, compressive, flexural, and splitting tensile strengths are evaluated. The results confirmed that increasing the amount of EPS increased the workability of LWSCCs while decreasing the strength value, but the compressive strength met the lower limit specified by ACI for structural applications. Additionally, there was a strong linear correlation between the mechanical results. The actual strengths compared with the empirical models presented in codes and literature studies found that the actual results are closest to ACI 363. [ABSTRACT FROM AUTHOR]

This paper presents an experimental work of using crushed glass mixed with the poorly graded sandy soil to investigate the possibility of shear strength parameters improvement using the direct shear test. The crushed glass is sieved and prepared for seven sets of percentages, the collected percentages of crushed glass represented a mix of glass retained on sieves No. 4, No. 8, No. 30, No. 100, and No. 200 and were added as a weight ratio of the sample for many cases. The main results of this work show that the mixing 10% of crushed glass for sieves No. 8, No. 200, and No. 50 increase the angle of internal friction of poorly graded sand (Ø˚) about 15%, 3%, and 29% respectively, and mixing 10% of crushed glass retained on sieve No. 4 decrease Ø˚ about 40%. [ABSTRACT FROM AUTHOR]

The article contains the results of selected tests of physical and mechanical properties of mortars differentiated in terms of the binder used: cement, epoxy, epoxy modified with PET waste glycolysate and polyester. Each type of mortar was modified by partial (0–20% vol.) substitution of sand with an agglomerate made from waste polyethylene. The obtained results were used to build a database of mortar properties, which was then analyzed with the use of three different techniques of knowledge extraction from databases, i.e., cluster analysis, decision trees and discriminant analysis. The average results of the properties tested were compared, taking into account the type of mortar, indicating those with the most favorable parameters. The possibilities and correctness of mortar classification with the use of the indicated "data mining" methods were compared. The results obtained confirmed that it is possible to successfully apply these methods to the classification of construction mortars and then to propose mortars with such a composition that will guarantee that the composite will have the expected properties. Both the presented method of plastic waste management and the proposed statistical approach are in line with the assumptions of the currently important concept of sustainable development in construction. [ABSTRACT FROM AUTHOR]

The concern about coconut shell disposal and natural fine aggregate depletion has prompted researchers to utilize coconut shell as aggregate in recent years. However, the majority of the present literature has focused on utilizing coconut shell as a coarse aggregate replacement in concrete via the traditional method. In this study, concrete incorporating coconut shell as a fine aggregate replacement (10–100%) was evaluated using permeability and water absorption tests in a systematic way. The response surface methodology (RSM) was first used to design the experimental works. In addition, an artificial neural network (ANN) and genetic expression programming (GEP) were also taken into account to mathematically predict the permeability and water absorption. Based on both experimental and theoretical modeling, three scenarios were observed. In the first scenario, high quality concrete was achieved when the replacement percentage of sand by coconut shell ranged from 0% to 10%. This is because both the permeability and water absorption were less than 1.5 × 10−11 m and 5%, respectively. In the second scenario, an acceptable and reasonable low permeability (less than 2.7 × 10−11 m/s) and water absorption (less than 6.7%) were also obtained when the replacement percentage increased up to 60%. In contrast, the high content coconut shell, such as 90% and 100%, developed concrete with a high permeability and water absorption and was defined in the third scenario. It was also inferred that both the experimental and mathematical models (ANN, GEP, and RSM) have consistent and accurate results. The correlation statistics indicators (R2) were greater than 0.94 and the error was less than 0.3, indicating a strong correlation and minimum error. In conclusion, coconut shell could act as a good alternative material to produce cleaner concrete with an optimum value of 50% as a fine aggregate replacement. [ABSTRACT FROM AUTHOR]

Reusing or recycling waste into new useful materials is essential for environmental protection. Herein, we used discarded polystyrene (PS) and fly-ash (FA) particles and a fabricated fly-ash incorporated polystyrene fiber (FA/PS fiber) composite. The electrospinning process produced continuous PS fibers with a good distribution of FA particles. The prepared nanofibers were characterized by state-of-the-art techniques. The performances of the composite nanofibers were tested for fire-retardant applications. We observed that the incorporation of FA particles into the PS fibers led to an improvement in the performance of the composite as compared to the pristine PS fibers. This study showed an important strategy in using waste materials to produce functional nanofibers through an economical procedure. We believe that the strategy presented in this paper can be extended to other waste materials for obtaining nanofiber membranes for various environmental applications. [ABSTRACT FROM AUTHOR]

The clustering of incomplete patterns is a very challenging task because the estimations may negatively affect the distribution of real centers and thus cause uncertainty and imprecision in the results. To address this problem, a new belief-based incomplete pattern unsupervised classification method (BPC) is proposed in this paper. First, the complete patterns are grouped into a few clusters by a classical soft method like fuzzy $c$ c -means to obtain the corresponding reliable centers and thereby are partitioned into reliable patterns and unreliable ones by an optimization method. Second, a basic classifier trained by reliable patterns is employed to classifies unreliable patterns and the incomplete patterns edited by the neighbors. In this way, most of the edited incomplete patterns can be submitted to specific clusters. Finally, some ambiguous patterns will be carefully repartitioned again by a new distance-based rule depending on the obtained reliable centers and belief functions theory. By doing this, a few patterns that are very difficult to classify between different specific clusters will be reasonably submitted to meta-cluster which can characterize the uncertainty and imprecision of the clusters due to missing values. The simulation results show that the BPC has the potential to deal with real datasets. [ABSTRACT FROM AUTHOR]

This study is the first to convert two waste materials, waste rice noodles (WRN) and red mud (RM), into a low-cost, high-value magnetic photocatalytic composite. WRN was processed via a hydrothermal method to produce a solution containing carbon quantum dots (CQDs). Simultaneously, RM was dissolved in acid to form a Fe 3+ ion-rich solution, which was subsequently mixed with the CQDs solution and underwent hydrothermal treatment. During this process, the Fe 3+ ions in RM were transformed into the maghemite (γ-Fe 2 O 3 ) phase, while CQDs were incorporated onto the γ-Fe 2 O 3 surface, resulting in the CQDs/γ-Fe 2 O 3 magnetic photocatalytic composite. Experimental results demonstrated that the WRN-derived CQDs not only facilitated the formation of the magnetic γ-Fe 2 O 3 phase but also promoted a synergistic interaction between CQDs and γ-Fe 2 O 3 , enhancing electron-hole pair separation and boosting the production of reactive radicals such as O 2 ·- and ·OH. Under optimized conditions (pH = 8, carbon loading: 10 wt%), the CQDs/γ-Fe 2 O 3 composite exhibited good photocatalytic performance against methylene blue, achieving a 97.6% degradation rate within 480 min and a degradation rate constant of 5.99 × 10 -3 min -1 , significantly outperforming RM and commercial γ-Fe 2 O 3 powder. Beyond methylene blue, this composite also effectively degraded common organic dyes, including malachite green, methyl violet, basic fuchsin, and rhodamine B, with particularly high efficiency against malachite green, reaching a degradation rate constant of 5.465 × 10 -2 min -1 . Additionally, due to its soft magnetic properties (saturation magnetization intensity: 16.7 emu/g, residual magnetization intensity: 2.2 emu/g), the material could be conveniently recovered and reused after photocatalytic cycles. Even after 10 cycles, it retained over 98% recovery and 96% photocatalytic degradation efficiency, underscoring its potential for cost-effective, large-scale photocatalytic water purification.

Global development has led to the generation of substantial levels of hazardous contaminants, including pesticides, which pose significant environmental risks. Effective elimination of these pollutants is essential, and innovative materials and techniques offer promising solutions. This study examines the modification of natural zeolite (clinoptilolite) and fly ash-based NaA and NaX zeolites with hexadecyltrimethylammonium bromide (CTAB) to create inexpensive adsorbents for removing 2,4-dichlorophenoxyacetic acid (2,4-D) herbicide from water. Detailed characterization of these materials was performed, along with an evaluation of the effects of pH, contact time, temperature, and initial 2,4-D concentration on their sorption capacities. The modified samples exhibited significant changes in elemental composition (e.g., reduced SiO 2 and Al 2 O 3 content, presence of Br) and textural properties. The adsorption of the pesticide was found to be an exothermic, spontaneous process of pseudo-second-order kinetics and was consistent with the Langmuir model. The highest sorption capacities were observed for samples modified with 0.05 mol L -1 CTAB, particularly for Cli CTAB-0.05 .

Regenerated cellulosic fibers were successfully spun from various waste cellulose sources (cotton linter, bagasse, and cardboard) suitable for use as a textile fibers using a wet spinning process with an ionic liquid/dimethyl sulfoxide (IL/DMSO) mixture as the solvent. The solubility of the waste cellulose sources in IL/DMSO varies according to the source of the raw material. Regenerated fibers can be spun from all the waste feedstock, the spinnability and fiber tensile strength is governed by the DP and chemical composition of the cellulose. The structural properties of the spun fibers are determined by x-ray diffraction, thermalgravimetric analysis, and scanning electron microscope. The results reveal that the properties of the starting materials and thus how the waste feed streams are pretreated have a significant impact on the mechanical properties, crystallite structure, thermal stability, and the morphology of the fibers.

The challenges posed by climate change/global warming are very alarming, and they have become the focal point of attention for researchers within the global environmental domains. The development of bioenergy can help salvage this situation as a renewable energy source that makes use of recycled waste materials to create useful energy products. This review study found that the development of sustainable bioenergy is environmentally friendly, and it has been proven to be a better means of recycling waste materials into final energy products for sustainable development. The study hereby concluded and recommended that environmental policies concerning the sustainable development of bioenergy should be adopted within the various nations' local laws and the global environment at large, as this will result in adhering strictly to international environmental legal frameworks regulating the prevention and reduction of waste materials. The possible correlation of bioenergy with the Sustainable Development Goals is also highlighted.

Sand and gravel are the world’s most exploited resources, even surpassing fossil fuels; they are mostly used for producing concrete. On the one hand, due to restrictions on the use of river sand in some regions of the world to conserve riverbeds, the demand for alternative fine aggregates in the construction sector has risen dramatically. The disposal of industrial by-products, on the other hand, is a serious challenge due to stringent environmental requirements. The use of industrial by-products as an alternative fine aggregate in concrete is a long-term, reasonable approach to excessive river mining and industrial by-product disposal. Although previous research on alternative fine aggregates is available, a complete assessment that considers many industrial by-products is lacking. As a result, this paper discusses the possible reuse of five industrial by-products as fine aggregate. The impact of various fine aggregate qualities on concrete attributes – such as flowability, compressive strength, water absorption, chloride permeability, ultrasonic pulse velocity, and drying shrinkage – is critically analysed and contrasted. According to the extensive research, copper slag and recycled glass with replacement amounts ranging from 0% to 100% have the least influence on both the mechanical and durability qualities of concrete. Overall, the qualities of concrete are heavily influenced by the characteristics of various fine particles. Furthermore, a framework for future research and challenges is presented to achieve reliable, eco-friendly, and cost-effective concrete.

This research studies the physical and mechanical properties of mortar composed of PVC plastic waste particles used as fine aggregate replacement material. PVC particles in quantities of 5%, 10%, 15%, 20%, 25%, and 30% by volume were used for sand fraction substitution. This quantity of PVC was used to formulate seven mixes with a cement content of 525 kg/m3 and a water-to-cement ratio (w/c) of 0.45. At 7 and 28 days, the compressive and splitting tensile strengths of the mortar's mechanical characteristics were evaluated. Additionally, the physical characteristics of density and absorption were investigated. The findings demonstrated that the mechanical properties and density of mortar containing PVC powder were minimized.