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The microwave chemical looping synergistic gasification characteristics of municipal solid waste polypropylene plastic and the organic solid waste water hyacinth are experimentally investigated in this study. In addition, the characterizations of oxygen carriers before and after the reaction are combined to analyze the evolution of the microscopic morphology of oxygen carriers and the changes in the relative contents of each valence state of Fe and O elements. The results show that an increase in the water hyacinth mixing ratio presents positive effects on tar cracking and a slight negative effect on syngas yield. At the water hyacinth mixing ratio of 75%, the cold gas efficiency and carbon conversion can reach maximum values of 77.64% and 69.9%, respectively. The H2 yield and H2/CO ratio in syngas can be also improved to 0.34 Nm3/kg and 1.62, respectively. In addition, a minimum tar yield of 0.133 g/g (fuel) can be obtained at this mixing ratio. Moreover, the addition of water hyacinth has a continuous increase effect on monocyclic aromatic hydrocarbon (MAH) products of tar, and a continuous decrease effect on naphthalene and bicyclic aromatic hydrocarbons (NAH) products. This work explores the synergistic properties of organic waste plastics and agroforestry wastes during microwave chemical looping gasification, which is a useful exploration for solving the environmental problems caused by waste materials and agroforestry wastes as well as realizing the resourceful utilization of solid wastes. [ABSTRACT FROM AUTHOR]

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With the continuous spread of COVID-19 (coronavirus disease 2019), a large number of medical protective suits (PS) have been used and discarded, causing great damage to the ecological environment. The main component of PS is polypropylene plastic, which will enter the oceans, rivers, and animals with groundwater and will not decompose for hundreds of years. Therefore, this global health crisis not only affects the health and economy of the world's population now but will also continue to disrupt our daily lives after the pandemic ends. The main objective of this study is to explore an effective method to reduce the biological and environmental hazards of medical waste by combining PS with concrete. Due to the excessive size of the PS, protective suit fibers (PSF) were obtained from PS by cutting. To investigate the possibility of using PS in concrete, a series of experiments were conducted, including a physical parameter test, compression test, split tensile test, ultrasonic pulse velocity test, scanning electron microscope (SEM), and finite element simulation. The results indicated that the introduction of PSF significantly enhanced the mechanical properties of concrete, and the maximum compressive strength and splitting tensile strength increased by 7.3% and 43.6%, respectively. The ultrasonic pulse velocity and density of concrete containing PSF decreased compared with the control group. The images of SEM show that PSF binds tightly to the cement matrix and hinders the propagation of micro-cracks. The introduction of PS into the concrete material leads to the improvement of the mechanical properties of concrete and the improvement of the overall quality of the concrete, which is of great significance for reducing the damage of medical waste to the environment. The originality of this work is that polypropylene fibers acquired from PS were put into concrete for the first time for performance testing. [ABSTRACT FROM AUTHOR]

This study was conducted to investigate the effect of polypropylene residue on heated palm oil against histopathological changes of small intestine on male white rat (Rattus norvegicus) wistar strain. Eighteen male white rats divided into three groups and were administered via peroral gavage with different treatments for five weeks. The treatment were Control (84 grams palm oil), P1 (84 grams palm oil with 2.3 grams plastic), and P2 (84 grams palm oil with 6.81 grams plastic). The histopathological changes of small intestine were examined by using Barthel Scoring method was analysed using Kruskal Wallis and continued with Mann-Whitney test. The result showed that were significant difference (p

This research was conducted to observe the effect of polypropylene plastic residue on heated palm oil against the histopathological changes on rat’s kidney. There were 18 male rats (Rattus norvegicus) that used as the examination animal and were divided into three groups and were given the mixture of heated palm oil and polypropylene plastic per oral with intubation needle. The treatment was done for five weeks. The treatment for P0 group was 84 g of palm oil, for P1 was 84 g of palm oil with 2.3 g of plastic, and for the P2 was 84 g of palm oil with 6.8 g of plastic. The histopathological changes of the kidney were observed using microscope with 400x magnification and the data was analysed using Kruskal-Wallis and continued with Mann Whitney U test. The result showed that there were significant differences between three groups of treatment (P

The utilization of agricultural residues and industrial wastes such as plastics to complement the use of solid wood in the manufacturing of composite panels presents an effective and efficient way of waste management for sustainable utilization of resources, especially in developing countries. Thus, the present study aimed at developing a cheap, safe, and energy-efficient composite board for effective house partitioning from sawdust and polypropylene plastic using cement and expanded polystyrene (EPS). Composite boards were developed from the blend of sawdust and polypropylene plastic using cement and expanded polystyrene (EPS) as adhesives. The composite boards were made by varying the sawdust-polypropylene ratio as well as the cement-EPS ratio. A constant load of 0.2 MPa was used in compacting the materials in a prepared aluminum mold under a hydraulic press machine. Physico-mechanical properties of the composite board such as density, water absorption, moisture content, compressive strength, tensile strength and flexural strengths were evaluated. The density of the composite boards varied from 490 to 630 kg/m3. The moisture content ranged from 6.04 to 9.09% while the water absorption ranged from 30 to 80% after 2 and 24 h immersion. The highest flexural, tensile and compressive strength for the composite boards were 7.10, 1.52, and 3.72 MPa, respectively. The composite samples met all the requirements of a partitioning wall except for flexural strength based on IS3087 standard. Cement and EPS were found to be suitable as adhesive for the development of composite boards from sawdust and polypropylene.

The underground granary has the advantages of energy conservation, land saving, low temperature, and environment protection. However, resistance of water and moisture from the groundwater has been main concerns for storing grains in underground granary. A plastic-concrete waterproof system using the polypropylene plastic (PP) as the waterproof layer was proposed. In this system, the plastic plate and concrete components were connected with plastic studs. Three plastic-concrete testing models were designed and fabricated based on the different stud spaces for the underground granary. In order to analyze the failure mode, failure mechanism, internal force and deformation of the plastic members under the water pressure, hydraulic loading tests were carried out. The test results showed that: the internal stress and displacement of the plastic plate increased with the increase of water pressure; the larger tensile force appeared at the joint area with the maximum stress unevenly distributed; the stress at mid-span was small with the maximum stress uniformly distributed. The displacement at the mid-span of the plastic plate increased linearly with increase of water pressure, whereas the displacement displacement at the joint changed slightly. On the basis of experimental analysis, the optimal design measures were proposed for the plastic-concrete waterproof system with plastic plate of 10 mm and given connection joints. When the water pressure reached its bearing capacity the failure modes of the plastic-concrete waterproof system were changed with change stud spacing. For the stud space of 200 mm, the joint weld seam was damaged at the water pressure of 180 kPa, which indicated that the overall water pressure bearing capacity of the testing model could be improved by enhancing the weld strength at the joint. For the stud space of 300 mm, the plastic plate was damaged with the water pressure capacity of 80 kPa, which indicated that the overall water pressure bearing capacity of the testing model could be enhanced by increasing the plate thickness. For the stud space of 400 mm, the joint weld seam was destroyed when the water pressure reached 38 kPa, the overall water pressure bearing capacity of the testing model could be enhanced by increasing the strength of the joint weld seam. The research results can provide a reference for waterproof design of the underground granary. [ABSTRACT FROM AUTHOR]

Viticulture has been expanding in tropical regions. However, the climate in these areas is generally favourable to the incidence of plant diseases, especially downy mildew. Plastic covers and warning systems have shown very positive results in disease control, but they are tools that have never been used simultaneously in a tropical area. The Vitis vinifera cv. BRS Morena table grape was evaluated as regards yield and quality under different downy mildew control strategies as carried out on vineyards trained on an overhead trellis system, covered by a black shading screen (BSS) or a braided polypropylene film (BPF), over a 3‐year period. Different grapevine downy mildew management approaches defined the treatments: Co) Control (no spraying); Ca) Conventional control (calendar); Ba) "Rule 3–10" (Atti Istituto Botanico, 8, 1947, 45); Ma25) Low‐infection efficiency—i0>25%; and Ma75) High‐infection efficiency—i0>75% (Plant Disease, 84, 2000, 549). The occurrence of downy mildew and the amount of damage inflicted on vine yield and grape quality are directly related to the period of the crop cycle when there is rainfall. The use of the Ma75 warning system (Plant Disease, 84, 2000, 549) under braided polypropylene film resulted, for the most part, in similar vineyard productivity compared to Ca, but did not influence the number of branches and its fertility. The other warning systems decreased productivity by 31.9% compared to Ca. It was not possible to establish a relationship between the occurrence of downy mildew and its influence on grape sweetness and acidity. The use of warning systems led to a substantial reduction in fungicide sprays, approximately 66.7 to 71.3%, compared to the calendar system commonly used by the vine growers, with the Ba (Atti Istituto Botanico, 8, 1947, 45) and Ma75 controls (Plant Disease, 84, 2000, 549) leading to the highest fungicide saving. [ABSTRACT FROM AUTHOR]

Abstrak. Penelitian ini bertujuan untuk menentukan jenis kemasan terbaik yang dapat mempertahankan mutu manisan kolang-kaling (Arenga pinnata L.) basah selama penyimpanan pada suhu ruang. Pada penelitian ini telah dikaji pengaruh jenis kemasan (plastik polipropilen (PP), botol plastik polipropilen (PP), dan botol kaca) dan lama penyimpanan (0, 5, 10, dan 15 hari) terhadap mutu manisan kolang-kaling basah. Hasil penelitian menunjukkan bahwa manisan kolang-kaling basah dengan mutu terbaik berdasarkan uji organoleptik dan kimia diperoleh dari kombinasi perlakuan manisan kolang-kaling basah yang dikemas menggunakan botol kaca dan lama penyimpanan 5 hari pada suhu ruang dengan karakteristik sebagai berikut: kadar air 35,75%, kadar gula 50,56 mg/L, kadar total asam 0,16%, nilai pH 4,40, total mikroba 0,34 CFU/ml, nilai organoleptik warna 3,83; aroma 3,90; dan tekstur 3,87. Wet ‘Kolang-Kaling’ Sweets (Arenga pinnata L.) Packaging Using Plastic Material and Glass Jar in Room Temperature Storage Abstract. The aim of this study was to determine the best type of packaging to maintain the quality of wet “kolang-kaling”(Arenga pinnata L.) sweets during storage at the room temperature. The effects of the type of packaging (polypropylene plastic (PP), polypropylene plastic cup (PP),and glass jar (jam jar)), and storage duration (0, 5, 10, and 15 days) on the quality of the wet “kolang-kaling” sweets were investigated.The results showed that the best quality of the wet “kolang-kaling” sweets based on the organoleptic and chemical analysis obtained from the wet “kolang-kaling” sweets were packed by using glass jars, and storage of 5 days at room temperature with the following characteristics: water content of 35,75%, sugar content of 50,56 mg/L, total acid content of 0,16%, pH value of 4,40, the total microbial of 0,34 CFU/ml. The organoleptic value of the best treatment: color of 3,83; flavor of 3,90; texture of 3,87.

Poplar plantations established on agricultural or forest land can be adversely affected by abundant competing vegetation already present or that grows after planting. In this paper, we investigate how different intensities of manual vegetation control and mulching with polypropylene plastic effect poplar growth during the first two years after planting. Field data revealed that, during the first year, mulching with polypropylene plastic increased seedling growth more than manual vegetation control when performed over the same area. However, during the second year, these differences diminished and poplar seedlings continued to grow at the same rate irrespective of vegetation control. The difference in growth between treatments seems to be related to the fact that mulching positively influences water and nutrient availability to a greater extent that manual vegetation control during the early phase of establishment. Vegetation control also affected biomass allocation, with a relative increase in leaf biomass and decrease in stem biomass. The increase in leaf biomass associated with vegetation control was a result of both an increase in leaf number and increased leaf size. [ABSTRACT FROM PUBLISHER]

[Display omitted] • A porous carbon was prepared from Microcystis aeruginosa and polypropylene. • Polypropylene enhanced the pore structure of porous carbon. • Porous carbon exhibited a high S BET (2140 m2/g) and abundant functional groups. • Porous carbon exhibited a high methylene blue adsorption capacity (667 mg/g). Porous carbon obtained by co-pyrolysis of plastic and biomass has received a lot of attention due to its excellent adsorption properties, and the pore structure plays an essential role in adsorption performance, however, the pore structure is still not well understood. Herein, we synthesized cyanobacteria-based porous carbon derived from cyanobacteria and polypropylene plastic by one-step method. CPC-800–30% exhibited a high BET surface area (2140 m2/g), pore volume up to 1.44 cm3/g. PP not only improved the pore structure of porous carbon, but also enriched the types of functional groups, such as O–H, N–H, C=O, and –CH, due to dehydroxylation or amino group decreased, resulting in the hydrogen radicals increased, hence PP had positive effect for biomass during co-pyrolysis. Meanwhile, CPC-800–30% showed excellent methylene blue (MB) adsorption capacity (667 mg/g). This work provided a new strategy for enhancing porous carbon structure via using PP as additive. [ABSTRACT FROM AUTHOR]

The coronavirus (COVID-19) pandemic has not only created a global health crisis, but it is also now threatening the environment. A multidisciplinary collaborative approach is required to fight against the pandemic and reduce the environmental risks associated with the disposal of used personal protective equipment (PPE). This paper explores an innovative way to reduce pandemic-generated waste by recycling the used face masks with other waste materials in civil constructions. In this research, for the first time, a series of experiments, including modified compaction, unconfined compression strength and resilient modulus tests, were conducted on the blends of different percentages of the shredded face mask (SFM) added to the recycled concrete aggregate (RCA) for road base and subbase applications. The experimental results show that RCA mixed with three different percentages (i.e., 1%, 2% and 3%) of SFM satisfied the stiffness and strength requirements for pavements base/subbase. The introduction of the shredded face mask not only increased the strength and stiffness but also improved the ductility and flexibility of RCA/SFM blends. The inclusion of 1% SFM to RCA resulted in the highest values of unconfined compressive strength (216 kPa) and the highest resilient modulus (314.35 MP). However, beyond 2%, increasing the amount of SFM led to a decrease in strength and stiffness. Unlabelled Image • A new and low carbon strategy is proposed to reduce pandemic-generated waste. • The inclusion of shredded face mask can improve ductility, flexibility and strength. • The disposed face masks can be used for pavement base/subbase applications. [ABSTRACT FROM AUTHOR]

With the ongoing global pandemic due to Coronavirus (COVID-19), the use of personal protective equipment (PPE), specifically single-use surgical masks, have been on a sharp incline. Currently, many countries are experiencing second and third waves of COVID-19 and as such have resorted to making face masks a mandatory requirement. The repercussions of this have resulted in millions of single-use face masks being discharged into the environment, washing up on beaches, floating beneath oceans and ending up in vulnerable places. The global pandemic has not only affected the economy and health of the world's population but now is seriously threatening the natural environment. The main plastic in single-use face masks is polypropylene which in landfill can take more than 25 years to break down. This paper explores an innovative way to use pandemic waste in concrete construction with the main focus on single-use face masks. Single-use masks have been cut-up by first removing the ear loops and inner nose wire to size and spread throughout five different mix designs to explore the possible benefits and uses within concrete. The masks were introduced by volume at 0% (control), 0.10%, 0.15%, 0.20% and 0.25% with testing focusing on compressive strength, indirect tensile strength, modulus of elasticity and ultrasonic pulse velocity to test the overall quality of the concrete. The introduction of the single-use face masks led to an increase in the strength properties of the concrete samples, as well as an increase in the overall quality of the concrete. However, beyond 0.20%, the trend of increasing strength began to decrease. • An innovative method is proposed to alleviate the waste generation issue associated with COVID-19. • The disposed surgical masks can be used to improve the strength of concrete. • The inclusion of 0.20% by volume of shredded surgical masks to concrete provided the highest strength properties. [ABSTRACT FROM AUTHOR]

At present, the catalysts used to produce high value products by catalytic pyrolysis of high calorific value waste plastics are expensive. In this study, the catalytic pyrolysis characteristics of reworked polypropylene (PP) plastics were studied by using low-cost kaolin with different particle sizes and HCl-modified kaolin. The results show that the catalysts reduced the condensate oil yield and increased the gas yield. C6–C20 was the major components of condensate oil ranging from 90% to 97% in catalyst pyrolysis by significantly decreasing the heavy components (above C20). Kaolin has high cracking efficiency of heavy components into alkanes and alkenes (the range of diesel components). The stronger acid sites on the modified kaolin further promoted the secondary cracking of diesel components, resulting in a great increase in the C6–C11 content. Moreover, HCl-modified kaolin significantly increased the aromaticity of the condensate oil because of the aromatization and Diels-Alder reaction of alkanes and alkenes. Meanwhile, kaolin significantly increased the yield of H 2 , and the H 2 yield was increased with the decrease of kaolin particle size. HCl-modified kaolin further promoted the yield and quality of gas. It is found that kaolin is a potential cheap and efficient pyrolysis catalyst. Image 1 • Kaolin as a cheap catalyst can promote the yield and quality of pyrolysis products. • HCl modification enhances the active functional groups (Al–O and Al–O–Si) of kaolin. • The specific surface area of particle size kaolin changes little after modification. • The 800 mesh and 1250 mesh HCl-modified kaolin has higher catalytic performance. • Adding modified kaolin increases the content of aromatic hydrocarbon by 0.74%–5.06%. [ABSTRACT FROM AUTHOR]