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The purpose of this study is to know the influence of palm oil fuel ash and metakaolin on the strength of concrete and crack resistance of reinforced concrete beam. An ordinary portland cement has been used in the concretes production where it is an important material to be considered due to its nature that reacts with every substance present. During the cement production, a significant amount of carbon dioxide is emitted from the clinker in rotary kiln and lot of energy is required in the production processes. Such an event can be prevented by replacing the part of cement with metakaolin (MK) and palm oil fuel ash (POFA). Aside from being a cementitious alternative, the materials can also contribute to a greener environment and more sustainable building, as POFA is available in Malaysia and may be used to substitute cement and minimize pollution.

This study assesses the effect of MK and POFA on the concrete in terms of compressive strength and cracks pattern of the reinforced concrete beam based on the relevant previous studies.

From this study, the compressive strength of concrete containing MK and POFA was higher than the control mix with the percentage of improvement in the range of 0.8%–78.2% for MK and 0.5%–14%, respectively. The optimum content of MK and POFA is between the range of 10% and 15% and 10% and 20%, respectively, to achieve high strength of concrete. Other than that, the inclusion of MK to the concrete mix improves the strength of reinforced concrete beams and reduces cracks on the surface of reinforced concrete beams, whereas the inclusion of POFA to the concrete mix increases the cracks on reinforced concrete beams. The cracks appeared within the flexure zone of every beam containing the MK and POFA.

It was found that the fineness of MK and POFA has a significant influence on the mechanical properties of concrete.

The purpose of this study was carried out to explore the potential use of carrageenan extracted from marine red seaweed (Kappaphycus alvarezii) collected from Munaikadu, Mandapam region, Ramanathapuram district, Tamil Nadu.

Biodegradable film was developed by using carrageenan extracted by using alcohol extraction method. To improve the mechanical properties of the film, rice starch was incorporated. The biodegradable films were made by phase inversion method with varied carrageenan concentration of 1%, 1.5% and 2% (w/v) and rice starch with concentration of 0%, 1%, 1.5% and 2% (w/v). Physical properties, optical properties, mechanical properties and other properties such as biodegradability, solubility and water vapor permeability of the developed biodegradable films were characterized. The results were analyzed in design expert software using Box–Behnken design.

Results show that the biodegradable film’s mechanical and water vapor permeability increases with an increase in carrageenan and rice starch concentration. The optimized film structure was obtained with carrageenan and rice starch composition of 1.5% and 2%, respectively.

The results shown a broad spectrum of commercial applications and future rice starch possibilities incorporated in the carrageenan-based biodegradable film.

Among various metal oxide nano particles, MgO NPs and ZnO nanoparticles (NPs) in particular are gaining increasing attention due to their multifunctional characteristics, low cost and compatibility with textile materials. Each type of nanoparticle excels over others in certain properties. As such, it is often crucial to carry out comparative studies of NPs to identify the one showing higher efficiency/output for particular applications of textile products.

In the investigation reported in this paper, ZnO NPs and MgO NPs were synthesised via sol-gel technique and characterised. For comparative analysis, the synthesised NPs were evaluated for multiple properties using standard procedures before and after being applied on cotton fabrics by a dip-pad-dry-cure method.

XRD and FTIR analyses confirmed the successful synthesis of ZnO and MgO NPs. Homogeneous formation of desired NPs and their dense and uniform deposition on the cotton fibre surface were observed using SEM. ZnO NPs and MgO NPs coatings on cotton were observed to significantly enhance self-cleaning/stain removal properties achieving Grade 5 and Grade 4 categories, respectively. In terms of ultraviolet (UV) protection, ZnO or MgO NP coated fabrics showed UPF values of greater than 50, i.e. excellent in blocking UV rays. MgO NPs exhibited 20% cleaning efficiency in treating reactive dye wastewater against ZnO NPs which were 4% efficient in the same treatment, so MgO was more suitable for such type of treatments at low cost. Both NPs were able to impart multifunctionality to cotton fabrics as per requirement of the end products. However, ZnO NPs were better for stain removal from the fabrics while MgO NPs were appropriate for UV blocking.

It was therefore clear that multifunctional textile products could be developed by employing a single type of cost effective and efficient nano particles.

The main aim of this study was to examine the effects of chicken eggshell (CES) and rice husk ash (RHA) as fillers on the mechanical and the thermal insulation properties of polyurethane coatings.

CES and RHA were ground via ball milling set at different parameters, and the smallest particles size obtained were selected and used as fillers. Fillers of different weight proportions were mixed with other components such as binder, solvent and pigment to form various coating formulations and test samples were made via dip coating. A series of characterisations were conducted to analyse the thermal and mechanical properties of the coating.

The smallest particle size of CES and RHA was obtained after both of them had undergone grinding process at 400 rpm within 180 min. Morphological studies revealed that CES and RHA have irregular shape and high porosity. In crystallographic analysis, CES mainly composed of pure calcite crystal structure and RHA contained amorphous silica. Both of fillers were found thermally stable up to 520 and 710°C for RHA and CES, respectively. In RHA individual system, as the RHA proportion increases, the thermal conductivity of the coating declined. In contrast, in the CES coating system, the thermal conductivity demonstrated an opposite trend. Thermal gravimetric analysis results displayed that by adding hybrid fillers, the residue weight and the thermal stability of the coatings were increased. In addition, the adhesion strength of the coating was increased as the filler weight content increased.

Fillers with nano-range size were expected to be produced in this research for better performance of the coating. However, the obtained fillers were limited to micron size through dry grinding method. Another drawback in this research was the coating technique which is dip coating. The coated substrates do not have uniform coating thickness and this subsequently influenced the performance.

A novel attempt has been made to study the formulation coating system by mixing CES and RHA as fillers which is also known as a hybrid system.

The purpose of this paper is to study Al-based green composite. To make composite samples of aluminium alloy (AA3105) with different weight percentages of rice husk ash (RHA) and eggshell (ES) particles as reinforcement, stir casting method was used.

Several other aspects, including the weight percent of reinforcing agent particles, the applied stress and the sliding speed, were taken into consideration. During the course of the wear test, the sliding distance that was recorded varied from a minimum of 1,000 m all the way up to a maximum of 3,135 m (10, 15, 20, 25 and 30 min). The typical range for normal loads is 8–24 N, and their speed is 1.58 m/s.

With the AA/ES/RHA composite, the wear rates decreases when the grain size of the reinforcing particles enhanced. Scanning electron microscopy images of worn surfaces show that at low speeds, delaminating and ploughing are the main causes of wear. At high speeds, ploughing is major cause of wear. Composites with better wear-resistant properties can be used in wide range of tribological applications, especially in the automotive industry. It was found that hardness increases at the same time as the weight of the reinforcement increases. Tensile and hardness were maximized at 10% reinforcement mix in Al3105.

In this work, ES and RHA has been used to develop green metal matrix composite to support green revolution as promoted/suggested by United Nations thus reducing the environmental pollution.

One of the sources for the increase in the carbon footprint on the earth is the manufacturing of cement, which causes a severer environmental impact. Abundant research is going on to diminish CO₂ content in the atmosphere by appropriate utilization of waste by-products of industries. Alkali-activated slag concrete (AASC) is an innovative green new concrete made by complete replacement of cement various supplementary cementitious raw materials. Concrete is a versatile material used in different fields of structures, so it is very important to study the durability in different exposures along with the strength. The purpose of this paper is to study the performance of AASC by incorporating quartz sand as fine aggregate under different exposure conditions.

The materials for this innovative AASC are selected based on preliminary studies and literature surveys. Based on numerous trials a better performance mix proportion of AASC with quartz sand is developed with 1:2:4 mix proportion, 0.8 alkali Binder ratio, 19 M of NaOH and 50% concentration of Na₂SiO₃. Subsequently, AASC cubes are prepared and exposed for 3, 7, 14, 28, 56, 90, 112, 180, 252 and 365 days in ambient, acid, alkaline, sulfate, chloride and seawater and tested for compressive strength. In addition, to study the microstructural characteristics, scanning electron microscope (SEM), energy dispersive X-ray analysis and X-ray diffraction analysis was also performed.

Long-term performance of AASC developed with quartz sand is very good in the ambient, alkaline environment of 5% NaOH and seawater with the highest compressive strength values of 51.8, 50.83 and 64.46, respectively. A decrease in compressive strengths was observed after the age of 14, 56 and 112 days for acid, chloride and sulfate exposure conditions, respectively. SEM image shows a denser microstructure of AASC matrix for ambient, alkaline of 5% NaOH and seawater.

The proposed AASC is prepared with a mix proportion of 1:2:4, so the other proportions of AASC need to verify. In general plain, AASC is not used in practice except in few applications, in this work the effect of reinforced AASC is not checked. The real environmental exposure in fields may not create for AASC, as it was tested in different exposure conditions in the laboratory.

The developed AASC is recommended in practical applications where early strength is required, where the climate is hot, where water is scarce for curing, offshore and onshore constructions exposed to the marine environment and alkaline environment industries like breweries, distilleries and sewage treatment plants. As AASC is recommended for ambient air and in other exposures, its implementation as a construction material will reduce the carbon footprint.

The developed AASC mix proportion 1:2:4 is an economical mix, because of low binder content, but it exhibits a higher early age compressive strength value of 45.6 MPa at the age of 3 days. The compressive strength increases linearly with age from 3 to 365 days when exposed to seawater and ambient air. The performance of AASC is very good in the ambient, alkaline environment and seawater compared to other exposure conditions.

Aluminium metal matrix composite (AMMC) is most popular in various industrial applications such as aerospace, automobile, marine, sports and many others. In common practice, silicon carbide, aluminum oxides, magnesium oxide, graphene and carbon nano tubes are the major reinforcing elements to prepare the AMMC. The purpose of this paper is to develop AMMCs reinforce with eggshell (ES) and rice husk ash (RHA).

Stir casting process is used for preparation of AMMC. From past few years, more emphasis is given to prepare the AMMCs using agro waste such as rice husk and/or ES as reinforcing materials. In this method, after the Al-matrix material is melted; it is stirred vigorously to form vortex at the surface of the melt, and the reinforcement material is then introduced at the side of the vortex. Stir casting process is a vortex and vigorous method to prepare the AMMCs. First, aluminum alloy (AA3105) is melted in the furnace when metal is in semisolid form. Reinforcement, i.e. ES and RHA are preheated at temperature 220°C and 260°C, respectively.

The result of AMMC shows that the tensile strength and hardness increased by using 22.41% and 45.5%, respectively, at 4.75 Wt.% each reinforcement, i.e. ES and RHA, and 1% Cr. The toughness and ductility of metal matrix composite (MMCs) have decreased up to 23.31% and 19.23% respectively by using 1% Cr, 4.75 wt. % ES and by 4.75 wt. % RHA of composite material.

In this work, Cr, waste ES and RHA have been used to develop green MMC to support the green revolution as promoted/suggested by United Nations, thus reducing the environmental pollution.

Plant-based eggs have recently been developed to provide consumers with a healthier, animal-friendlier and more sustainable alternative to conventional eggs. The purpose of this paper is to investigate intrinsic and extrinsic attribute preferences for three prototypes of plant-based egg, namely the liquid, powder and egg-shaped.

Nine focus groups in the United Kingdom and nine in Italy were conducted, with a total of 180 participants. A thematic analysis of results was conducted.

In terms of intrinsic product attributes, consumers' preferences for colour, shape, taste, ingredients, nutrients, method of production and shelf-life for plant-based eggs were revealed. Regarding the extrinsic attributes, preferences for price, packaging, country of origin and product naming emerged. Similarities and differences between consumers from the two countries are also discussed. Differences in preferences also emerged between vegan and non-vegan consumers.

This study adds to the existing knowledge on consumers' preferences for new plant-based food alternatives and identifies future quantitative approaches based on qualitative findings.

Results from this study can assist plant-based egg manufacturers in improving their products in line with consumers' expectations, which may help reducing risk of product failure.

This study is the first to investigate consumers' preferences, expectations and needs for new food products like plant-based eggs and provides information that can be practically applied by manufacturers, as well as suggestions for future research.

The main objective of the study is to present a systematic process that can assess, compare and benchmark different geographical levels environmental impacts of using sustainable materials at construction stage.

Current study presents a methodological framework to evaluate environmental impacts at the construction stage of using sustainable materials through a cradle-to-gate process based quantitative LCA study. Scenario analyses and an optimisation analysis using Monte-Carlo simulation are conducted to investigate the influence of external factors on environmental impacts at different geographical regions.

Materials account for 98% of greenhouse gas (GHG) emissions. Carbon monoxide (CO) and non-methane volatile organic compounds (NMVOC) record significant non-GHG emissions. Particulate matter (PM₁₀) emissions are significant from transportation and equipment. High significance of global warming potential (GWP) (38.98%) and photochemical oxidation formation potential (POFP) (34.49%) at global level and eutrophication potential (EP) (52.83%) and human toxicity potential (HTP) (25.30%) impacts at local level were observed. Shortest transportation distance reduces 14.91% PM₁₀ and 4.69% nitrous oxide (NO_x) emissions. Inventory variations have major influence on POFP impact at global level. Local level impacts are not significantly affected by inventory variations. Optimisation analysis indicated, high fly ash in concrete increase local level carbon emissions, if OPC concrete transportation distance is less than 23.7 km.

Use of case-specific information for validation may lack generalisation. However, methodology can be used for future sustainable decision making over using sustainable materials in construction.

The study estimate environmental impacts at different geographical levels when sustainable materials are used for construction.

In the current scenario, air pollution and soil pollution from the industries wastes are one of the major problems all over the world. Further, disposal of these wastes from industries are very costly. However, several attempts were carried out by various researchers in the past to use these wastes. One of the most common waste products is bagasse from sugar industries. These hazardous bagasse wastes lead to air and soil pollution. This study aims to recycle bagasse waste in the development of aluminium base composite as partial replacement of ceramic particles.

In the present investigation, recycled bagasse waste was used in the development of aluminium base composite as partial replacement of ceramic particles such as SiC, Al₂O₃ and B₄C. Production industries of these ceramic particles (SiC, B₄C and Al₂O₃) emit huge amount of greenhouse gases such as N₂O₃, CH₄, CO₂ and H₂O. These green house gases produce lots of environment problem. Furthermore, production of these ceramic particles is also costly. AA6061 aluminium alloy was taken as matrix material. Composite material was developed using the stir casting technique.

Microstructure results showed proper distribution of bagasse ash and MgO powder in the aluminium base metal matrix composite. It was notified from analysis that minimum corrosion loss and minimum porosity were found for Al/2.5% bagasse ash/12.5% MgO powder composite. For the same composition, hardness and thermal expansion were also observed better as compared to other selected compositions. However, density and cost of composites continuously decrease by increasing percentage of bagasse ash in development of composite.

Results showed about 11.30% improvement in tensile strength, 11.64% improvement in specific strength and 40% improvement in hardness by using bagasse ash as reinforcement with MgO powder in development of aluminium base composite.