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1.
Buildings ; 13(4):919, 2023.
Article in English | ProQuest Central | ID: covidwho-2294825

ABSTRACT

Plastic waste causes severe environmental impacts worldwide and threatens the lives of all creatures. In the medical field, most of the equipment, especially personal protective equipment (PPE), is made from single-use plastic. During COVID-19, the usage of PPE has increased, and is disposed of in landfills after being used once. Worldwide, millions of tons of waste syringes are generated from COVID-19 vaccination. A practical alternative to utilizing this waste is recycling it to reinforce building materials. This research introduces an approach to using COVID-19 syringe plastic waste to reinforce building material as composite concrete. Reinforced fiber polymer (FRP) concrete materials were used to mold cylindrical specimens, which underwent mechanical tests for mechanical properties. This study used four compositions with 0%, 5%, 10%, and 15% of FRP to create cylindrical samples for optimum results. Sequential mechanical tests were carried out on the created samples. These specimens were cured for a long period to obtain water absorption capability. After several investigations, the highest tensile and compressive strengths, approximately 2.0 MPa and 10.5 MPa, were found for the 5% FRP composition samples. From the curing test, the lowest water absorbability of around 5% was found for the 5% FRP composition samples.

2.
Discover Food ; 3(1):2, 2023.
Article in English | ProQuest Central | ID: covidwho-2254853

ABSTRACT

Orange-fleshed sweet potato (OFSP) and pumpkin fruit are underutilized crops with great potential for the production of high-quality bread with health-enhancing properties. However, the incorporation of nonconventional flour in bread formula may influence the dough and bread quality properties. This study investigated the effect of partial substitution of wheat flour with OFSP (10–50%) and pumpkin flour (10–40%), baking temperature (150–200 °C) and baking time (15–25 min) on the quality properties of the composite dough and bread using response surface methodology (RSM). Dough rheological, bread physical and textural properties were analyzed, modelled and optimized using RSM. Satisfactory regression models were developed for the dough and bread quality attributes (R2 > 0.98). The dough development time, crust redness, hardness, and chewiness values increased while optimum water absorption of dough, specific volume, lightness, springiness, and resilience of bread decreased significantly (p < 0.05) with increasing incorporation of OFSP and pumpkin flour in the bread formula. Additionally, the specific volume, crust redness, crumb hardness, and chewiness of the composite bread increased significantly (p < 0.05) with increasing baking temperature from 150 to 180 °C but reduced at higher baking temperatures (≥ 190 °C). The staling rate declined with increased OFSP and pumpkin flour whereas increasing the baking temperature and time increased the bread staling rate. The optimized formula for the composite bread was 78.5% wheat flour, 11.5% OFSP flour, 10.0% pumpkin flour, and baking conditions of 160 °C for 20 min. The result of the study has potential applications in the bakery industry for the development of functional bread.

3.
Water ; 14(19):3100, 2022.
Article in English | ProQuest Central | ID: covidwho-2066637

ABSTRACT

While Rwanda is aiming at environmental pollution resilience and green growth, some industries are still discharging untreated effluent into the environment. This study gives a general overview of the compliance level of industrial effluent discharge in Rwanda and the linked negative environmental impacts. It comprises qualitative and quantitative analyses of data obtained from wastewater samples collected from five selected industries in Rwanda. The selected industries had previously been audited and monitored by the Rwanda Environment Management Authority (REMA), due to complains from neighboring residents. The study found that the effluent discharge from wastewater treatment plants (WWTP) for all concerned industries failed to comply with (i) oil and grease (O&G) national and international tolerable parameter limits or the (ii) fecal coliforms national standard. In addition, a compliance level of 66.7% was observed for key water quality monitoring parameters (pH, dissolved oxygen (DO), biochemical oxygen demand (BOD), chemical oxygen demand (COD), total suspended solids (TSS), and heavy metals (i.e., lead (Pb), cadmium (Cd), and chromium (Cr)). Following these study findings, one industry was closed by the REMA for deliberately discharging untreated effluent into an adjacent river. This study recommends the adoption of the best available technology for effluent treatment, installation or renovation of existing WWTPs, and the relocation to industrial zones of industries adjacent to fragile environments.

4.
Polymer Reviews ; 2022.
Article in English | Scopus | ID: covidwho-1984894

ABSTRACT

Vaccine development is among the critical issues for ceasing the COVID-19 pandemic. This review discusses the current usage of biomaterials in vaccine development and provides brief descriptions of the vaccine types and their working mechanisms. New types of vaccine platforms (next-generation vaccines and DNA- or mRNA-based vaccines) are discussed in detail. The mRNA vaccine encoding the spike protein viral antigen can be produced in a cell-free system, suggesting that mRNA vaccines are safer than “classic vaccines” using live or inactivated virus. The mRNA vaccine efficacy is typically high at approximately 95%. However, most mRNA vaccines need to be maintained at −20 or −70 degrees for storage for long periods (half a year) and their transportation because of mRNA vaccine instability in general, although mRNA vaccines with unmodified and self-amplifying RNA (ARCT-154, Arcturus), which have a lyophilized form, have recently been reported to be kept at room temperature. mRNA vaccines are typically entrapped in lipid nanoparticles composed of ionizable lipids, polyethylene glycol (PEG)-lipids, phospholipids, and cholesterol. These components and their composition affect mRNA vaccine stability and efficacy and the size of the mRNA vaccine. The development of an improved mRNA vaccine entrapped in sophisticated biomaterials, such as novel lipid nanoparticles, using new types of biopolymers or lipids is necessary for high efficacy, safe transportation and long-term storage of the next generation of mRNA vaccines under mild conditions. © 2022 Taylor & Francis Group, LLC.

5.
Applied Sciences ; 12(11):5388, 2022.
Article in English | ProQuest Central | ID: covidwho-1892764

ABSTRACT

Featured ApplicationThis research aims at understanding the sources of plastic litter in a freshwater body, assessing the possible production of secondary microplastics (MPs).Plastic waste dispersion is a well-recognized environmental threat, despite continuous efforts towards improving waste disposal management over the last few decades. Plastic litter is known to strongly impact upon water bodies and shorelines, affecting the health of ecosystems and impacting upon the aesthetic value of sites. Moreover, plastic waste that is abandoned on beaches contributes towards different degradation processes that potentially lead to the formation of secondary microplastics (MPs), with likely cascade effects upon the whole ecosystem. In this view, this study aims to characterize the plastic beach litter found on the shores of the western basin of Como Lake (Italy) to better understand the origin of MPs in littoral sediments, including the recognition of object typologies and the chemical characterization of polymers using Fourier-transformed infrared analysis (FTIR). The results highlighted that the most abundant polymers on beaches are polypropylene (PP) and polyethylene (PE), representing 73% of the collected polymers. This confirms that floating, low-density polymers are more likely to accumulate on beaches. Moreover, almost 66% of litter is represented by commonly used manufactured items (disposable objects, packaging, and everyday items). This evidence, combined with the analysis of the main environmental features of the sampling sites (the main winds, distance to urban areas, and the presence of tributaries) indicate that abundance of beached litter is mainly linked to beach accessibility and the local winds. These results highlight that multiple factors affect the environmental fate of plastic litter and give insights into the assessment of secondary microplastics in beach sediments.

6.
Sustainability ; 14(10):6366, 2022.
Article in English | ProQuest Central | ID: covidwho-1871345

ABSTRACT

This article provides a systematic literature review on the integrated approach of bio-based plastic food packaging in a circular economy. It focuses on the following key areas: (1) the role of bio-based plastic food packaging in a circular product design strategy and material choice in the preproduction life cycle stage;(2) the role of bio-based plastic food packaging in circular resource management systems and the product disposal life cycle stage;and (3) an optimal bio-based plastic food packaging application in regard to prioritising end-of-life treatment. While there are dedicated publications on the role of packaging in a circular economy, circular packaging design, packaging waste management, and bio-origin plastic applications in food packaging, this article aims to provide an integrated review and recommendations on the best bio-based plastic food packaging material selection, applications based on a circular economy, and scenarios on waste/resource management that prioritise end-of-life treatment. Three of the current most popular bio-based plastic materials in the flexible and rigid food packaging categories were selected: starch blends, bio-PE, and PLA for flexible food packaging and PLA, bio-PET, and bio-PE for rigid packaging. This article highlights the fact that a smart material choice in the circular design strategy is a key factor that has a direct impact on the last packaging life cycle stage (disposal), and concludes that bio-based plastic materials are a way to close the food packaging loop, either by re-use or recycling. This article also provides recommendations on the best bio-based plastic food packaging material selection, and applications based on the circular economy and waste management that prioritise end-of-life treatment. The research results indicate a research niche for the application of re-usable biodegradable materials in food packaging. The findings of this research allow product designers and packaging companies to advance the understanding of the most efficient bio-based plastic food packaging integration into the circular economy via decision making of product material choice and end-of-life treatment. Based on the results of this article, scholars can develop new themes for further research.

7.
Sustainability ; 14(8):4425, 2022.
Article in English | ProQuest Central | ID: covidwho-1810132

ABSTRACT

Plastic waste (PW) is one of the most rapid-growing waste streams in municipal solid waste all over the world. India has become a global player in the plastic value chain. Despite low consumption, domestic generation and imports create a significant burden on the overall waste management system, which requires in-depth understanding of the scenario and pathways that can mitigate the crisis. Although Indian researchers have widely researched technology-related issues in academic papers, a substantial knowledge gap exists in understanding the problem’s depth and possible solutions. This review article focuses on current plastic production, consumption, and waste generation in India. This review article mainly analyzes data and information regarding Indian PW management and highlights some critical issues such as reverse supply chain, effective PW management, source-specific recovery, and PW rules in India. Comprehensively, this review will help to identify implementable strategies for policymakers and research opportunities for future researchers in holistic PW management and recycling in India, focusing on the circular economy and sustainable development goals.

8.
Energies ; 15(8):2719, 2022.
Article in English | ProQuest Central | ID: covidwho-1809793

ABSTRACT

Polymers and plastics are crucial materials in many sectors of our economy, due to their numerous advantages. They also have some disadvantages, among the most important are problems with the recycling and disposal of used plastics. The recovery of waste plastics is increasing every year, but over 27% of plastics are landfilled. The rest is recycled, where, unfortunately, incineration is still the most common management method. From an economic perspective, waste management methods that lead to added-value products are most preferred—as in the case of material and chemical recycling. Since chemical recycling can be used for difficult wastes (poorly selected, contaminated), it seems to be the most effective way of managing these materials. Moreover, as a result this of kind of recycling, it is possible to obtain commercially valuable products, such as fractions for fuel composition and monomers for the reproduction of polymers. This review focuses on various liquefaction technologies as a prospective recycling method for three types of plastic waste: PE, PP and PS.

9.
The Annals of the University of Dunarea de Jos of Galati. Fascicle VI. Food Technology ; 45(2):134-146, 2021.
Article in English | ProQuest Central | ID: covidwho-1716494

ABSTRACT

The focus of this study was to produce composite flour with nutritional and functional potentials from underutilized and inexpensive crops, which can be used in food formulations as a substitute to composite flours from commonly used and expensive crops. The proximate, mineral, and amino acid compositions, resistant starch content and in vitro starch digestibility of breadfruit-bambara groundnut (100:0, 90:10, 80:20, 70:30, and 60:40 respectively) composite flours were investigated using standard methods. Data generated were subjected to statistical analysis. Inclusion of bambara groundnut in the composite flours significantly (p<0.05) increased protein (5.06-16.96%), ash (1.54-2.71%), fat (1.06-1.96%), potassium (727.82-797.73 mg/100g), phosphorus (143.36-177.32 mg/100g), magnesium (92.71-117.05 mg/100g) and resistant starch (11.45-21.98%) contents, while it significantly (p<0.05) reduced fibre (4.65-5.39%), carbohydrate (65.3379.69%), sodium (48. 64-71.25 mg/100g), and calcium (57.65-64.50 mg/100g) contents, as well as in vitro starch digestibility (40.41-58.75%). All the essential amino acids were present;they constituted 34.69 - 37.94% of the total amino acid. The predicted protein efficiency ratio ranged from 2.14 to 2.82. This study suggests that breadfruit-bambara groundnut composite flours may find usefulness in different food formulations and may exhibit lower postprandial hyperglycemia which is important for obese and diabetic patients.

10.
Sustainability ; 13(24):13887, 2021.
Article in English | ProQuest Central | ID: covidwho-1598977

ABSTRACT

In order to meet the environmental needs caused by large plastic waste accumulation, in the road construction sector, an effort is being made to integrate plastic waste with the function of polymer into asphalt mixtures;with the purpose of improving the mechanical performance of the pavement layers. This study focuses on the effect of a recycled mixture of plastic waste on the chemical, thermal, and rheological properties of designed asphalt blends and on the identification of the most suitable composition blend to be proposed for making asphalt mixture through a dry modification method. Thermo-gravimetric analysis, differential scanning calorimetry, and Fourier transform infrared spectroscopy analysis were carried out to investigate the effect of various concentrations and dimensions of plastic waste (PW) on the neat binder (NB). The frequency sweep test and the multiple stress creep and recovery test were performed to analyze the viscoelastic behavior of the asphalt blends made up of PW in comparison with NB and a commercial modified bitumen (MB). It has been observed that the presence of various types of plastic materials having different melting temperatures does not allow a total melting of PW powder at the mixing temperatures. However, the addition of PW in the asphalt blend significantly improved the aging resistance without affecting the oxidation process of the plastic compound present in the asphalt blend. Furthermore, when the asphalt blend mixed with 20% PW by the weight of bitumen is adopted into the asphalt mixture as polymer, it improves the elasticity and strengthens the mixture better than the mixture containing MB.

11.
IOP Conference Series. Earth and Environmental Science ; 930(1), 2021.
Article in English | ProQuest Central | ID: covidwho-1569510

ABSTRACT

During the COVID-19 pandemic, the increased use of plastic for personal protective equipment (PPE), single-use plastic bags, and food packaging raised significant environmental concerns. This study aimed to investigate the shape, abundance, and type of microplastics in the sediment of Jakarta Bay, specifically Tanjung Priok, Ancol Beach, and Sunda Kelapa Port. Sediment was collected using an Ekman sediment grab sampler and was extracted using the density separation method. The microplastics were counted and categorized according to the shape under a microscope. The differences in microplastic abundance in three different stations were determined using a one-way ANOVA. The polymer of microplastics was identified using Fourier Transform Infra-Red (FTIR). The results show that the abundance of the microplastics from coastal sediment was highest in the Sunda Kelapa Port (45066.67 ± 5205.13 particle/kg dry weight), which is significantly different (p<0.05) from Tanjung Priok (40533.33 ± 2444.04 particle/kg dry weight) and Ancol Beach (34666.67 ± 2444.04 particle/kg dry weight). Fragments dominated the shape of microplastic in Tanjung Priok, Ancol Beach, and Sunda Kelapa Post, comprising 36%, 40%, 38%, respectively, followed by fiber, film, and pellet. The FT-IR tests indicated that polypropylene (PP), polyethylene (PE), polystyrene (PS), and polyamide are the most prevalent microplastic polymers.

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