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The purpose of this paper is to determine the use of BLA along with SiC as economical reinforcements to enhance the mechanical behavior of hybrid composite. The purpose of this research is the development of cost-effective aluminum hybrid metal matrix composites.

The present research work investigation evaluated the mechanical properties of Al-4.5%Cu alloy, Al-4.5Cu/10SiC, Al-4.5Cu/10SiC/2BLA and Al-4.5Cu/10SiC/4BLA composites by the Stir casting method. The fabricated composites were analyzed using optical microscopy (OM), scanning electron microscopy (SEM), and hardness and tensile test.

The microstructure modification with the addition of reinforcement particles in the matrix alloy and clear interface in between matrix and particles are observed. The density of the composite increased with the addition of SiC and decreased with the addition of BLA in comparison with that of matrix alloy. The hardness and tensile strength of the single-reinforced composite and hybrid composites improved with the addition of reinforcement particles. The strengthening of composites was due to load-bearing capacity of reinforcement particles over the matrix alloy and increased dislocation density of composites materials. The tensile failure mechanism of the composites is reveled with SEM analysis.

The papers reports the development of cost-effective and light weight aluminum hybrid composites with remarkable enhancement in the mechanical and tribological properties with the addition of BLA as economical reinforcement along with SiC.

The density, hardness and tensile values of fabricated aluminium composites were presented in this paper for the use in the engineering applications where the weight and cost are consider as a primary factors.

Bioconcrete is widely believed to be environmentally beneficial over conventional concrete. However, the process of bioconcrete production involves several steps, such as waste recovery and treatment, that potentially present significant environmental impacts. Existing life-cycle assessments of bioconcrete are limited in the inventory and impact analysis; therefore, they do not consider all the steps involved in concrete production and the corresponding impacts. The purpose of this study is to extensively study the cradle-to-gate environmental impacts of all the production stages of two most common bioconcrete types (i.e. sludge-based bioconcrete and cement kiln dust-rice husk ash (CKD-RHA) bioconcrete) as opposed to conventional concrete.

A cradle-to-gate life-cycle assessment process model is implemented to systematically analyze and quantify the resources consumed and the environmental impacts caused by the production of bioconcrete as opposed to the production of conventional concrete. The impacts analyzed in this assessment include global warming potential, ozone depletion potential, eutrophication, acidification, ecotoxicity, smog, fossil fuel use, human toxicity, particulate air and water consumption.

The results indicated that sludge-based bioconcrete had higher levels of global warming potential, eutrophication, acidification, ecotoxicity, fossil fuel use, human toxicity and particulate air than both conventional concrete and CKD-RHA bioconcrete.

The contribution of this study to the state of knowledge is that it sheds light on the hidden impacts of bioconcrete. The contribution to the state of practice is that the results of this study inform the bioconcrete production designers about the production processes with the highest impact.

The purpose of this paper is to examine the use of phragmites australis ash (PAA) in cementitious systems to achieve sustainable construction.

In this paper, the properties of mortar containing PAA as partial cement replacement are determined. The PAA is produced through slow burning in a closed system to minimize the CO₂ emission. A total of four mortar mixes are prepared with PAA replacement levels ranging from 0% to 30% by weight. The water to binder and the proportions of binder to sand are 0.55 and 1:3 by weight, respectively. The properties tested are density, compressive strength, flexural strength, ultrasonic pulse velocity, water absorption by total immersion and capillary rise. Testing is conducted at 1, 7, 28 and 90 days.

While there is a decrease in strength as the amount of PAA increases, there is strong indication of pozzolanic reaction in the presence of PAA. This is in agreement with the results reported by Salvo et al. (2015), where they found noticeable pozzolanic activities in the presence of straw ash, which is rich in SiO₂ and relatively high K₂O content. At 90 days of curing, there is a decrease of 5% in compressive strength at 10% PAA replacement. However, at 20% and 30% replacement, the reduction in compressive strength is 23% and 32%, respectively. The trend in flexural strength and ultrasonic pulse velocity is similar to that in compressive strength. The water absorption by total immersion and capillary rise tends to increase with increasing amounts of PAA in the mix. There seems to be a linear relationship between water absorption and compressive strength at each curing age.

The Phragmites australis plant used in this investigation is obtained from one location and this present a limitation as the type of soil may change the properties. Also one method of slow burning is used. Different burning methods may alter the composition of the PAA.

This outcome of this research will contribute towards sustainable development as it will make use of the waste generated, reduce the amount of energy-intensive cement used in construction and help generate local employment in the area where the Phragmites australis plant grows.

To the best knowledge of the authors, the ash from the Phragmites australis plant has not been used in cementitious system and this research can be considered original as it examines the properties of mortar containing PAA. Also, the process of burning in a closed system using this material.

The conflicting results on the corrosion characteristics of aluminium matrix composites reinforced with agrarian waste have stimulated an investigation on the hardness and corrosion rate of sugar palm fibre ash (SPFA) reinforced LM26 Al/alloy composite by varying the SPFA from 0 to 10 wt% in an interval of 2 wt%. This paper aims to discuss the aforementioned issue.

The composites were produced via stir-casting and the hardness was determined using a Vickers hardness testing machine, corrosion rate was examined through the weight loss method by immersion in 0.5, 1.0 and 1.5 M hydrochloric acid (HCl) at temperatures of 303, 318, and 333 K for the maximum duration of 120 h. The morphological study was conducted using a scanning electron microscope (SEM) on the samples before and after immersion in HCl.

The incorporation of SPFA improved the hardness of the alloy from 58.22 to 93.62 VH after 10 wt% addition. The corrosion rate increases with increased content of SPFA, the concentration of HCl and temperature. The least corrosion rate of 0.0272 mpy was observed for the LM26 Al alloy in 0.5 M after 24 h while the highest corrosion rate of 0.8511 mpy was recorded for LM26 Al/10 wt% SPFA in 1.5 M HCl acid after 120 h. The SEM image of corroded samples revealed an increased number of pits with increased SPFA content.

The work is limited to SPFA up to 10 wt% as reinforcement in LM26 Al alloy, the use of HCl as corrosion medium, temperatures in the range of 303–333 K, and a weight loss method were used to evaluate the corrosion rate.

The corrosion rate was determined for LM26 Al/SPFA composites with various amounts of SPFA in 0.5, 1.0 and 1.5 M HCl at 303, 318 and 333 K and compared with the matrix alloy.

This paper aims to produce hybrid reinforcement for the development of aluminium matrix composites using ball-billing technique to avoid or reduce the problem of agglomeration of the reinforcement during casting.

In the present investigation, a mixture of silicon carbide (SiC) and rice husk ash (RHA) powder in equal weight percentage ratio 4:4 (1:1) was alloyed mechanically in a ball-mill at distinct milling times of 15, 30, 45, 60 and 75 h. Morphological Characterization and density measurements of the ball-milled powder were carried out after different intervals of milling times.

The results revealed that the process of ball milling is a novel technique for the conversion of two or more powders in to an integer powder and reduces the problem of agglomeration also. The density measurement results revealed that an increasing trend of density initially and reduction of the density with the increase of milling time. The density value of the combined particles became comparable to the density of aluminium at the milling time of 75 h for the equal weight percentage ratio 4:4 (1:1) of SiC and RHA.

The manuscript highlights the research work related to the development of the reinforcement for the aluminium hybrid composites by ball milling process. The use of this process for the development of the reinforcement not only reduces the problem of the agglomeration but reduces the density mismatch of the reinforcement and matrix material also.

The United Nations has demonstrated a commitment to preserving the ecosystem through its 2030 sustainable development goals agenda. One crucial objective of these goals is to promote a healthy ecosystem and discourage practices that harm it. Building materials production significantly contributes to the emissions of greenhouse gases. This poses a threat to the ecosystem and prompts a growing demand for sustainable building materials (SBMs). The purpose of this study is to investigate SBMs to determine their utilization in construction operations and the potential impact their application could have on construction productivity.

A systematic review of the existing literature in the field of SBMs was conducted for the study. The search strings used were “sustainable” AND (“building” OR “construction”) AND “materials” AND “productivity”. A total of 146 articles were obtained from the Scopus database and reviewed.

Bio-based, cementitious and phase change materials were the main categories of SBMs. Materials in these categories have the potential to substantially contribute to sustainability in the construction sector. However, challenges such as availability, cost, expertise, awareness, social acceptance and resistance to innovation must be addressed to promote the increased utilization of SBMs and enhance construction productivity.

Many studies have explored SBMs, but there is a dearth of studies that address productivity in the context of SBMs, which leaves a gap in understanding. This study addresses this gap by drawing on existing studies to determine the potential implications that using SBMs could have on construction productivity.

The present study seeks to evaluate the role of village bamboo management in the rural landscape of North East India in global climate change mitigation.

A set of 100 home gardens and 40 bamboo groves were selected from Irongmara and Dargakona village, in Cachar district, Assam, North East India through random sampling. Sampling was done mostly for smallholders. Culm growth, carbon storage, carbon sequestration and carbon in litter floor mass and soil of bamboo growing areas in homegarden was explored from 2003‐2007.

Culm growth extension revealed the brief periodicity of culm growth in a single growth period. Of the total carbon storage soil contributed 84.6 per cent of the total (50.1 Mg ha⁻¹) followed by carbon in above ground vegetation 15 per cent (9 Mg ha⁻¹) and carbon in litter floor mass 0.4 per cent (0.2 Mg ha⁻¹).

Bamboo plantation development and its management in home gardens has social, ecological and economical benefits for the rural life in North East India and its promotion can become an effective choice for climate change mitigation strategy.

Bamboo forms an important component in the traditional home garden system of North East India where the practice of bamboo cultivation and management provides an important sink for CO₂. Village bamboos play an important role in local economics, societies and environments and, considering its potential to mitigate global climate change, the authors recommend the promotion of bamboo in agroforestry expanding practices and rehabilitation of degraded lands. Management of village bamboos in rural landscape is highlighted in context to environmental sustainability and as a sink measure under the Clean Development Mechanism (CDM) of Kyoto Protocol.

The following definitions and standards for food products have been adopted as a guide for the officials of this Department in enforcing the Food and Drugs Act. These are standards of identity and are not to be confused with standards of quality or grade; they are so framed as to exclude substances not mentioned in the definition and in each instance imply that the product is clean and sound. These definitions and standards include those published in S. R. A., F. D. 2, revision 4, and those adopted October 28, 1936.

This article aims to study the tensile properties of a functionally graded composite structure with Al–18wt%Si alloy as the matrix material and silicon carbide (SiC) particles as the reinforcing element. More specifically, the study's primary objective is to optimize the composition of the material elements using a robust statistical approach.

In this research, the composite material is fabricated using a combination of stir casting and the centrifugal casting technique. Moreover, the test specimen required to study the tensile strength are prepared according to the ASTM (American Society for Testing and Materials) standards. Eventually, optimal composition to maximize the tensile property of the material is determined using the mixture design approach.

The investigation results imply that the addition of the SiC plays a crucial role in increasing the tensile strength of the composite. The optical microstructural images of the composite show the adequate distribution of the reinforcing particles with the matrix. The proposed regression model shows better predictability of tensile strength. In addition, the methodology aids in optimizing the mixture component values to maximize the tensile strength of the produced functionally graded composite structure.

Little work has been reported so far where a hypereutectic Al–Si alloy is considered the matrix material to produce the composite structure. The article attempts to make a composite structure by using a combination of stir casting and centrifugal casting. Furthermore, it employs the mixture design to optimize the composition and predict the model of the study, which is one of a kind in the field of material science.

This study aims at extracting and characterizing palm leaf fibers from Elaeis guineensis species of palm trees found in Ethiopia.

The fibers were extracted using three methods: manually, through water retting and chemically with sodium hydroxide. Physical parameters of the extracted fibers were evaluated, including tensile strength, fiber fineness, moisture content, degradation point and functional groups. Its cellulose, hemicellulose and lignin contents were also analyzed.

The results showed that the palm leaf fibers have a comparable fiber strength (170-450 MPa), elongation (0.95-1.25 per cent), fiber length (230-500 mm) and moisture regain (8-10 per cent) to jute, sisal and flax and thus can be used for technical textile application.

The fibers extracted using the water retting method had better properties than the other extraction methods. Its fiber length of 307 mm, cellulose content of 58 per cent, strength of 439 MPa and elongation of 1.24 per cent were the highest for all the extracted fibers. When compared with other fibers, palm leaf fiber properties such as tensile strength (439 MPa), elongation (1.24 per cent), moisture content (7.9-10.4 per cent and degradation point (360-380°C) were consistent with those of jute, sisal and ramie fibers. Hence, palm leaf fibers can be used for technical textile applications such as composite reinforcement.