ABSTRACT
Fibre-reinforced plastic (FRP) materials are attracting growing interest because of their high specific mechanical properties. These characteristics, in addition to a high level of tailorability and design of freedom, make them attractive for marine, aerospace, automotive, sports and energy applications. However, the large use of this class of material dramatically increases the amount of waste that derives from end-of-life products and offcuts generated during the manufacturing processes. In this context, especially when thermosetting matrices are considered, the need to deeply study the recycling process of FRPs is an open topic both in academic and industrial research. This review aims to present the current state of the art of the most affirmed recycling technologies used for polymeric composites commonly used in industrial applications, such as carbon and glass FRPs. Each recycling method (i.e., chemical, thermal and mechanical) was analysed in terms of technological solutions and process parameters required for matrix dissolution and fibre recovery, showing their advantages, drawbacks, applications and properties of the recycled composites. Therefore, the aim of this review is to offer an extensive overview of the recycling process of polymeric composite materials, which is useful to academic and industrial researchers that work on this topic.
ABSTRACT
The main idea of the present study was to investigate the impact of the ongoing world crisis on the socio-economic issues in Serbia concerning building materials usage and purchase. This research fills in the gaps in the literature and contributes to the comprehension of how the crisis has affected salaries, market pricing, and materials consumption in the building sector. The data are gathered through a questionnaire and analyzed using a statistical methodology (frequencies, descriptive statistics, and Spearman's correlations). Most of the former studies investigated the surveys conducted on specialists in the field, while this study analyzed the perspectives of random people. Socio-demographic issues are analyzed along with materials consumption before and after the crisis. A special emphasis is given to ecological awareness and novel materials usage. Additionally, it captures a broad shift in the economy and ecological consciousness in a developing country. The majority of respondents are open to using novel building materials and products, but their choice would largely be influenced by cost, the amount of effort involved, and their understanding of the advantages. Statistical approaches revealed that the crisis has a considerable impact on the markets for construction and building supplies, altering consumers' decisions when purchasing. This contribution lays the groundwork for developing countries in the modern world to improve sustainability and adopt circular thinking. Professionals in Serbia need to have a more eco-aware mindset and enhance how they provide pertinent information to potential clients. This study is limited by the number of respondents. For future mathematical modeling and forecasting, more answerers are needed.
ABSTRACT
In a resource-constrained world, there is ongoing concern over the exploitation and potential future shortage of Earth’s natural resources. In this paper, we present the results of two pilot studies in which we used drone technology with spatial mapping tools and environmental and economic analysis to map illegal waste sites. Besides the technical feasibility, we aimed at understanding the benefits, costs, and tradeoffs of extracting the materials stocked therein, transforming illegal waste sites into valuable resources. The innovation of our work is reflected in the integration of existing technologies for aerial mapping and economic\environmental assessment methodologies for promoting a local circular economy. The pilot results suggest that it is feasible to identify valuable materials left on the ground in the form of unattended, illegally disposed waste. Our initial national estimates for the illegal waste cleanup based on the pilot results suggest that the treatment cost in Israel can be reduced by 58 million USD and even reach zero, with the potential to generate up to 82.8 million USD profits. Finally, we link our results to the Sustainable Development Goals framework and suggest how mapping and implementing the recycling potential can promote achieving some of the goals. Our work provides missing data that the state, local authorities, contractors, and companies that monitor and manage waste and recycled raw materials may find useful.
ABSTRACT
This review aims to discuss the current advances in green methods for the isolation and characterization of pectic polysaccharides with a focus on unconventional extraction sources and their bioactive applications in the pharmaceutical industry as new biopolymers or drug delivery systems. The physicochemical, structural, and functional properties of crude pectins, fractions (pectin oligosaccharides), and their domains (homogalacturonan, rhamnogalacturonan-I, rhamnogalacturonan-II, and xylogalacturonan) isolated from underutilized raw and agro-waste materials are compared using novel analytical techniques, such as Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), 1H-13C heteronuclear single quantum coherence (HSQC) nuclear magnetic resonance (NMR) spectroscopy, high-performance size exclusion chromatography (HPSEC), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), and rheology. The advantages and drawbacks of green and innovative methods are analyzed to indicate the best ecofriendly techniques for extracting bioactive pectins from unconventional sources and their structural effects. Chemical modifications and potential pharmaceutical applications of bioactive pectins are considered to assess the effects of their biological activity in cancer and cardiovascular diseases. Finally, trends and future opportunities related to bioactive pectins and their fragments isolated from unconventional pectin sources are critically analyzed to provide guidelines for research in innovative technological developments and their possible applications in emerging public health problems such as the COVID-19 pandemic. © 2022 Elsevier B.V.
ABSTRACT
Organised waste pickers in Colombia are formally recognised as subjects of special protection and as providers of the public service of recycling. As a consequence, they now receive remuneration for their work, but this was not always the case. This article highlights the strategies waste pickers used to successfully demand their rights while exploring the tensions and contradictions surrounding the formalisation of waste pickers as public service providers of recycling. These include a lack of sufficient guarantees from the government, attempts by private companies to appropriate waste pickers' benefits, and a lack of respect by both the state and private businesses for the recognition of their rights in law. It concludes that there is an inherent tension between the main objectives of the waste pickers-to improve their working conditions and overcome poverty and vulnerability-and that of the state, which promotes free market competition in the provision of public services.
ABSTRACT
The pandemic of COVID -19 has brought many changes to wildlife globally positively or negatively. During lock downs the abundance of many wild species has increased due to decease in human disturbance in area. This study is designed to compare two landfills situated 22 km apart in the Gujranwala, Punjab in terms of avifauna diversity, abundance and foraging behavior during COVID-19 pandemic. The field observations using the total count method of population census revealed the abundance of contrasting avian species at both sites with a very low values of the diversity index (H= 1.146 Chianwali & H=1.697 Gondalawala ) and species evenness (E= 0.423 Chianwali & E= 0.587 Gondalawala). A large variation in bird's population was recorded at both landfills, i.e. N > 17,300 at one landfill (Chianwali) and N> 26,200 at the other (Gondalawala). Time dependent variation in population was also observed. Cattle egret was dominant species (~75% of population) at the Chianwali landfill site while the Black kite (~55% of population) was the dominant species at Gondalawala landfill. House crow was the second dominant species at both sites. Birds were grouped into categories based on ecological behaviors such as dominance, opportunists, insectivory etc. The study finds that each landfill has its own specific character depending upon the geographical location, accessibility of birds to landfills, and management practices such as presence of boundary wall and artificial lights. Moreover, it also finds that COVID -19 lockdown provided an opportunity to wild avian species to exploit human rehabilitated areas abundantly where there presence was very few because of dominance of human beings and their activities.