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The present work focuses on evaluating the physical and mechanical characteristics of geopolymer concrete (GPC) by replacing the sodium silicate waste (SSW) in place of traditional river sand. The aim is to create eco-friendly concrete that mitigates the depletion of conventional river sand and conserves natural resources. Additionally, the study seeks to explore how the moisture content of filler materials affects the performance of GPC.

SSW obtained from the sodium silicate industry was used as filler material in the production of GPC, which was cured at ambient temperature. Instead of the typical conventional river sand, SSW was substituted at 25 and 50% of its weight. Three distinct moisture conditions were applied to both river sand and SSW. These conditions were classified as oven dry (OD), air dry (AD) and saturated surface dry (SSD).

As the proportion of SSW increased, there was a decrease in the slump of the GPC. The setting time was significantly affected by the higher percentage of SSW. The presence of angular-shaped SSW particles notably improved the compressive strength of GPC when replacing a portion of the river sand with SSW. When exposed to elevated temperatures, the performance of the GPC with SSW exhibited similar behavior to that of the mix containing conventional river sand, but it demonstrated a lower residual strength following exposure to elevated temperatures.

Exploring the possible utilization of SSW as a substitute for river sand in GPC, and its effects on the performance of the proposed mix. Analyzing, how varying moisture conditions affect the performance of GPC containing SSW. Evaluating the response of the GPC with SSW exposed to elevated temperatures in contrast to conventional river sand.

The purpose of this study is to improve the mechanical properties, thermal insulation properties and flame retardant properties of polyethylene terephthalate (PET), the organic montmorillonite (OMMT)/SiO₂ aerogel/PET composites and fibers were prepared, and the effects of the OMMT/SiO₂ aerogel on the structure, thermal conductivity and flame retardance of the OMMT/SiO₂ aerogel/PET composites and their fibers were systematically investigated.

The OMMT/SiO₂ aerogel/PET composites and fibers were prepared by in-situ polymerization and melt spinning using SiO₂ aerogel as thermal insulation filler and OMMT (DK2) as comodified filler.

The experimental results showed that OMMT improved the crystallization properties of PET. Compared with the crystallinity of SiO₂ aerogel/PET composites (34.8%), SiO₂ aerogel/PET composites and their fibers reached 45.1% and 49.2%, respectively. The breaking strength of the OMMT/SiO₂ aerogel/PET composite fibers were gradually increased with the OMMT content. When the content of OMMT was 0.8 wt.%, the fracture strength of the composite fibers reached 4.40 cN/dtex, which was 54% higher than that of the SiO₂ aerogel/PET fiber. In addition, the thermal insulation properties of the composites and their fibers were improved by addition of fillers, and at the same time reached the flame retardant level. The thermal conductivity of the 0.8 wt.% OMMT/SiO₂ aerogel/PET composites was 101.78 mW/(m·K), which was 49.3% and 58.8% lower than that of the SiO₂ aerogel/PET composites and the pure PET, respectively. The thermal conductivity of the fiber fabrics woven from the 0.8 wt.% OMMT/SiO₂ aerogel/PET composites was 28.18 mW/(m·K), which was 29.0% and 44.6% lower than that of the SiO₂ aerogel/PET composite fiber fabrics and PET fiber fabrics. The flame retardancy of the composites was improved, with an limiting oxygen index value of 29.2% for the 0.8 wt.% OMMT/SiO₂ aerogel/PET composites, which was 4.1% higher compared to the SiO₂ aerogel/PET composites, and achieved the flame retardant level.

The SiO₂ aerogel/PET composites and their fibers have good mechanical properties, flame retardant properties and thermal insulation properties, exhibited good potential for application in the field of thermal insulation, such as warm clothing. Nowadays, as the energy crisis is becoming more and more serious, it is very important to improve the thermal insulation properties of PET to reduce energy losses and mitigate the energy crisis.

In this study, PET based composites and their fibers with excellent mechanical properties, thermal insulation properties and flame retardant property were obtained by using three-dimensional network porous silica aerogel with low density and low thermal conductivity as the thermal insulation functional filler and two-dimensional layered OMMT as the synergetic modified filler.

This study aims to evaluate in situ oxidative polymerization of aniline (Ani) as a post-processing method to promote extrusion-based 3D printed parts, made from insulating polymers, to components with functional properties, including electrical conductivity and chemical sensitivity.

Extrusion-based 3D printed parts of polyethylene terephthalate modified with glycol (PETG) and polypropylene (PP) were coated in an aqueous acid solution via in situ oxidative polymerization of Ani. First, the feedstocks were characterized. Densely printed samples were then used to assess the adhesion of polyaniline (PAni) and electrical conductivity on printed parts. The best feedstock candidate for PAni coating was selected for further analysis. Last, a Taguchi methodology was used to evaluate the influence of printing parameters on the coating of porous samples. Analysis of variance and Tukey post hoc test were used to identify the best levels for each parameter.

Colorimetry measurements showed significant color shifts in PP samples and no shifts in PETG samples upon pullout testing. The incorporation of PAni content and electrical conductivity were, respectively, 41% and 571% higher for PETG in comparison to PP. Upon coating, the surface energy of both materials decreased. Additionally, the dynamic mechanical analysis test showed minimal influence of PAni over the dynamic mechanical properties of PETG. The parametric study indicated that only layer thickness and infill pattern had a significant influence on PAni incorporation and electrical conductivity of coated porous samples.

Current literature reports difficulties in incorporating PAni without affecting dimensional precision and feedstock stability. In situ, oxidative polymerization of Ani could overcome these limitations. However, its use as a functional post-processing of extrusion-based printed parts is a novelty.

The purpose of this study is to develop black pigmented ceramic stoneware bodies that integrate various aspects of material composition and color potential. Recent research has explored black pigmented calcium aluminosilicate glass (BPCG), a specialized material known for its unique properties, which holds promise for transforming the color capabilities of traditional ceramics.

In this investigation, initially composite ceramic sample (B-1) was prepared by milling process prior to sieve analysis to attain the particle size within 44 microns. Microanalysis and morphology and thermography were studied by energy-dispersive X-ray spectroscopy, scanning electron microscope and thermogravimetric analysis and found Sample-B-1 received attractive properties like firing shrinkage, porosity, bulk density and firing strength along with good pyro-plastic properties at various temperatures like 950°C, 1050°C, 1000°C and 1180°C. Furthermore, BPCG-assisted pigmented ceramic composites were synthesized with B-1 matrix. CIE lab investigation of the attributed composites (C-series) within selective soaking range of 5–20 min was performed, and the investigation found that prominent black hue appeared (L: 24.09, a*: −0.17, b*: −0.49) for C-10 containing appeared phases of Di-Co-Silicide (26%), Ni-Chromite, Stilpnomelane (rich in iron) as obtained by X-ray diffraction studies.

Ceramic material played a significant role in the realms of art and craft, as well as in technology. The artistic facet reveals concepts or ornamentation, while the craft echoes both traditional and functional appeal. Technology, on the other hand, involves the logical implementation behind the creation.

This C-10 Sample comprised the lower percentage of mullite which attributed that the BPCG homogeneously mixed in the matrix of base (B-1) and appeared as spinal staff. Therefore, BPCG was a potential candidate for ceramic metallization, and this traditional metallization processes often faced some challenges like uniformity and mixing in the ceramic composite domain practices. This study aimed to open up new avenues for artistic decoration and bridging the gap between traditional craftsmanship and modern technology. Furthermore, BPCG’s role in color assessment through shocking techniques added an exciting concept for the ceramic practitioners, designers or ceramic educators.

One of the often-employed building constituents in the construction sector is concrete, which involves hydration of cement, leading to the generation of carbon footprints during its production. Also, massive amount of natural aggregate is illegally mined, which poses serious environmental issues along with ecological misbalance. Researchers are in continuous search of appropriate substitutes to mitigate those challenges and develop innovative concrete mix. Consequently, depletion of natural resources, the disturbances to the environmental and ecological imbalance will reduce. The purpose of this study is to develop a Portland Slag Cement based novel sustainable concrete incorporating Alccofine and Recycled Refractory Brick as fractional replacement of cement and fine aggregate, respectively and evaluate its destructive, non-destructive and microstructural properties.

M25 grade of concrete adopting 0.45 water-binder proportion, with diverse percentage of Alccofine as fractional substitution of cement and 20% of recycled refractory brick (RRB) as fine aggregate, has been cast and evaluated for diverse mechanical strength following a curing of 7, 14 and 28 days. Scanning electron microscopic analysis has been carried out to study the microstructural changes in the specimens.

Supplementary use of Alccofine enhanced normal compressive strength of sustainable concrete mix blended with Portland Slag Cement by a large amount at all levels of 7, 14 and 28 days of curing. Test results indicated development of a favourable high-strength sustainable concrete mix by substituting cement with Alccofine.

This manuscript has demonstrated the possibility of developing sustainable concrete blends by incorporating Alccofine 1203 and RRB as partial replacement of Portland Slag Cement and natural fine aggregate, respectively. The strength and potential of concrete incorporating RRB for wider and special application in adverse environmental conditions having higher thermal gradient, as RRB is a valuable waste from high temperature kiln and furnaces. Alccofine 1203 has been included in the concrete mix as an alternative to Portland Slag Cement to improve the mechanical strength properties and durability of concrete intended for adverse environmental application.

The purpose of this study is to experimentally determine whether mechanical properties of concrete can be improved by using olive pomace aggregates (OPA) as a substitute for natural sand. Two types of OPA were tested by replacing an equivalent amount of natural sand. The first type was OPA mixed with olive mill wastewater (OMW), and the second type was OPA not mixed with OMW. For each type, two series of concrete were produced using OPA in both dry and saturated states. The percentage of partial substitution of natural sand by OPA varied from 0% to 15%.

The addition of OPA leads to a reduction in the dry density of hardened concrete, causing a 5.69% decrease in density when compared to the reference concrete. After 28 days, ultrasonic pulse velocity tests indicated that the resulting material is of good quality, with a velocity of 4.45 km/s. To understand the mechanism of resistance development, microstructural analysis was conducted to observe the arrangement of OPA and calcium silicate hydrates within the cementitious matrix. The analysis revealed that there is a low level of adhesion between the cement matrix and OPA at interfacial transition zone level, which was subsequently validated by further microstructural analysis.

The laboratory mechanical tests indicated that the OPCD_OPW (5) sample, containing 5% of OPA, in a dry state and mixed with OMW, demonstrated the best mechanical performance compared to the reference concrete. After 28 days of curing, this sample exhibited a compressive strength (R_c) of 25 MPa. Furthermore, it demonstrated a tensile strength of 4.61 MPa and a dynamic modulus of elasticity of 44.39 GPa, with rebound values of 27 MPa. The slump of the specimens ranged from 5 cm to 9 cm, falling within the acceptable range of consistency (Class S2). Based on these findings, the OPCD_OPW (5) formulation is considered optimal for use in concrete production.

This research paper provides a valuable contribution to the management of OPA and OMW (OPA_OMW) generated from the olive processing industry, which is known to have significant negative environmental impacts. The paper presents an intriguing approach to recycling these materials for use in civil engineering applications.

This paper aims to design and manufacture an equine hand prosthesis using additive manufacturing, with an estimated useful life of one year. This approach offers a fast and affordable manufacturing alternative while ensuring the horse's safety, comfort and functionality.

The ground reaction force and the frequency of a horse’s walking were obtained from the literature. Mechanical tests were conducted on specimens with different manufacturing directions to determine the mechanical properties of the printed material. Finite element simulations, along with fatigue equations were used to design a geometry that respected the stress constraints. Subsequently, a prototype was manufactured in thermoplastic polyurethane using additive manufacturing technique.

With the aid of the proposed methodology, a new low-cost equine hand prosthesis is developed, and a prototype is manufactured. And in accordance with the design requirements, this prosthesis is intended to exhibit proper durability.

This work presents an alternative way for horses facing amputation, offering a solution where euthanasia can be avoided through the use of a prosthesis to replace a part of the amputated limb. This approach could not only extend the reproductive life of matrices with high commercial value but also preserve the lives of animals with sentimental value to the owner.

To the best of the authors' knowledge, this is the first study of an equine hand prosthesis model designed for and manufactured by additive manufacturing.

This study aims to assess carbon emissions in urban aged residential buildings in Qingdao, Shandong Province, constructed prior to 2000, and to evaluate retrofitting and rebuilding strategies for potential carbon reduction.

Field investigations and literature reviews were conducted to identify key factors influencing carbon emissions, such as shape coefficient, window-to-wall ratio and envelope structure. A combination of generalization and mathematical statistical methods was used to classify buildings based on construction year, form, structural type and energy-saving goals. Cluster analysis was employed to extract six typical building models.

Results demonstrate that building form complexity positively correlates with carbon emissions per unit area, while longer lifespans reduce emission intensity. Retrofitting exhibits shorter carbon payback periods (1.62–3.92 years) than rebuilding (18.7–49.94 years), indicating superior environmental performance. Pre-1986 buildings are advised for demolition/rebuilding due to limited retrofit benefits. For 1986–1995 buildings, retrofitting is recommended if structurally viable. Post-1996 buildings favor retrofitting over new construction for its shorter payback and lower emissions, enhancing long-term carbon reduction.

This study contributes to the understanding of carbon emissions in urban aged residential buildings by considering various factors and providing specific recommendations for retrofitting and rebuilding strategies tailored to different construction periods. Additionally, it highlights the importance of building form complexity and remaining lifespan in determining carbon emissions, offering insights for sustainable urban development and carbon reduction initiatives.

The aim was not to perform a systematic review but firstly to search in PubMed, Science Direct, Scopus and Web of Science databases on the papers published in the last five years using tools for reviewing the statement of preferred information item for systematic reviews without focusing on a randomized analysis and secondly to perform a bibliometric analysis on the properties of films and coatings added of tocopherol for food packaging.

On January 24, 2022, information was sought on the properties of films and coatings added of tocopherol for use as food packaging published in PubMed, Science Direct, Scopus and Web of Science databases. Further analysis was performed using bibliometric indicators with the VOSviewer tool.

The searches returned 33 studies concerning the properties of films and coatings added of tocopherol for food packaging, which were analyzed together for a better understanding of the results. Data analysis using the VOSviewer tool allowed a better visualization and exploration of these words and the development of maps that showed the main links between the publications.

In the area of food science and technology, the development of polymers capable of promoting the extension of the shelf life of food products is sought, so the knowledge of the properties is vital for this research area since combining a biodegradable polymeric material with a natural antioxidant active is of great interest for modern society since they associate environmental preservation with food preservation.

The purpose of this paper was to prepare a ternary hierarchical rough particle to accelerate the anti-corrosive design for coastal concrete infrastructures.

A kind of micro-nano hydrophobic ternary microparticles was fabricated from SiO₂/halloysite nanotubes (HNTs) and recycled concrete powders (RCPs), which was then mixed with sodium silicate and silane to form an inorganic slurry. The slurry was further sprayed on the concrete surface to construct a superhydrophobic coating (SHC). Transmission electron microscopy and energy-dispersive X-ray spectroscopy mappings demonstrate that the nano-sized SiO₂ has been grafted on the sub-micron HNTs and then further adhered to the surface of micro-sized RCP, forming a kind of superhydrophobic particles (SiO₂/HNTs@RCP) featured of abundant micro-nano hierarchical structures.

The SHC surface presents excellent superhydrophobicity with the water contact angle >156°. Electrochemical tests indicate that the corrosion rate of mild steel rebar in coated concrete reduces three-order magnitudes relative to the uncoated one in 3.5% NaCl solution. Water uptake and chloride ion (Cl^-) diffusion tests show that the SHC exhibits high H₂O and Cl^- ions barrier properties thanks to the pore-sealing and water-repellence properties of SiO₂/HNTs@RCP particles. Furthermore, the SHC possesses considerable mechanical durability and outstanding self-cleaning ability.

SHC inhibits water uptake, Cl^- diffusion and rebar corrosion of concrete, which will promote the sustainable application of concrete waste in anti-corrosive concrete projects.