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Due to the excellent functionality of graphene, the research on fiber modification by graphene has been receiving more and more attentions recently, and many research findings have been conducted. However, the purpose of this paper is to focus on the fiber modification method and corresponding modified fiber properties, but the research on processing of the modified fiber, especially the textile process, is little. Therefore, in the paper, the properties of one kind of textile GN fiber and the spinning method of the GN fiber blend yarn and the functionalities of corresponding fabric are studied.

In the paper, the properties of nylon fiber modified by graphene (GN) were studied first. Then, according to the tested results, one new blending process of the GN fiber and cotton fiber was given, and corresponding properties of the blend yarns were tested and analyzed. Finally, the knitted fabrics were produced using the spun blend yarns, and the antibacterial property, electromagnetic shielding property, anti-ultraviolet performance, anti-static performance and conventional mechanical, and appearance thermal-wet comfort properties were tested and comparatively analyzed.

The tested results showed that the functionality of all fabrics was effective due to the addition of the graphene in the fiber, especially the antibacterial property. With the increasing of the GN fiber in the blend yarns, the functionality of all fabrics was also increased first and then achieved stability.

One new blending process of the GN fiber and cotton fiber was given. In the spinning, the combed cotton sliver was produced first, and then was torn into small parts of combed cotton sliver fiber by hand. Then, the treated GN fibers and cotton fibers were mixed for the first time, and corresponding GN/C carding sliver was produced. In this blend processing, the mixed cotton fiber was used to improve the sliver processing of the GN fiber. Then, in the drawing process, the required number of GN/C carding sliver and combed cotton sliver were fed simultaneously, and GN fibers and cotton fibers were mixed for the second time, and corresponding four kinds of GN/JC blend yarns were produced. In this blend processing, the mixed cotton fiber was used to regulate the blending ratio.

A Polymer Engineering Directorate and Industry Sponsored Programme in the Department of Materials, Cranfield Institute of Technology.

THE first tentative steps in the use of composite materials for primary structures were taken in 1940 when, a Blenheim main spar was built of Gordon Aerolite, a material developed by Dr. Norman de Bruyne's firm, Aero Research Ltd. of Duxford (now part of the Ciba‐Geigy Group). It comprised unbleached flax thread skein formed with phenolic resin in a heated press to form what was probably the world's first advanced composite material.

The purpose of this paper is to investigate the effect of a hydrostatic initial stress and the gravity field on a fiber-reinforced thermoelastic medium with an internal heat source that is moving with a constant speed.

A general model of the equations of the formulation in the context of the three-phase-lag model and Green-Naghdi theory without energy dissipation.

The exact expressions for the displacement components, force stresses, and the thermal temperature for the thermal shock problem obtained by using normal mode analysis.

A comparison made between the results of the two models for different values of a hydrostatic initial stress as well as an internal heat source. Comparisons also made with the results of the two models in the absence and presence of the gravity field as well as the reinforcement.

The purpose of this study is to analyze the thermo-diffusion process in a semi-infinite nonlocal fiber-reinforced double porous thermoelastic diffusive material with voids (FRDPTDMWV) in light of the fractional-order Lord–Shulman thermo-elasto-diffusion (LSTED) model. By virtue of Eringen’s nonlocal elasticity theory, the governing equations for the considered material are developed. The free surface of the substrate is governed by the inclined mechanical load and thermal and chemical shocks.

With the aid of the normal mode technique, the solutions of the nondimensional coupled governing equations have been obtained.

The expressions of field variables are obtained analytically. By using MATHEMATICA software, various graphical implementations are presented to describe the impacts of angle of inclination, fractional-order and nonlocality parameters. The present model is also validated on the basis of some comparative studies with some preestablished cases.

As observed from the literature survey, many different studies have been carried out by taking into account the deformation analysis in nonlocal double porous thermoelastic material structures and thermo-mechanical interaction in fiber-reinforced medium under fractional-order thermoelasticity theories. However, to the best of the authors’ knowledge, no research emphasizing the thermo-elasto-diffusive interactions in a nonlocal FRDPTDMWV has been carried out. Moreover, the effect of fractional-order LSTED theory on fiber-reinforced thermoelastic diffusive half-space with double porosity has not been illuminated till now, which significantly defines the novelty of the conducted research.

Discusses the use of carbon fibre plates for strengthening concrete structures and research and development by Professor Urs Meier at The Swiss Federal Laboratories for Material Testing and Research (EMPA), on which the Carbodur system is based. Plate bonding, using mild steel strips, is now a proven process but, like all technology, progress moves the boundaries forward. Its replacement with carbon fibre strips has now created a system which is simpler to use, quicker to install and highly cost‐effective. A three‐year project has also been established by the Department of Trade and Industry, under the structural Composites LINK collaborative research scheme, to examine strengthening of bridges using polymeric composite materials (ROBUST).

Contact problems are among the most difficult ones in mechanics. Due to its practical importance, the problem has been receiving extensive research work over the years. The finite element method has been widely used to solve contact problems with various grades of complexity. Great progress has been made on both theoretical studies and engineering applications. This paper reviews some of the main developments in contact theories and finite element solution techniques for static contact problems. Classical and variational formulations of the problem are first given and then finite element solution techniques are reviewed. Available constraint methods, friction laws and contact searching algorithms are also briefly described. At the end of the paper, a bibliography is included, listing about seven hundred papers which are related to static contact problems and have been published in various journals and conference proceedings from 1976.

The purpose of this paper is to study two-dimensional deformations in a nonlocal, homogeneous, isotropic, rotating thermoelastic medium with temperature-dependent properties under the purview of the Green-Naghdi model II of generalized thermoelasticity. The formulation is subjected to a mechanical load.

The normal mode analysis technique is adopted to procure the exact solution of the problem.

For isothermal and insulated boundaries, discussions have been made to highlight the influences of rotational speed, nonlocality, temperature-dependent properties and time on the physical quantities.

The exact expressions for the displacement components, stresses and temperature field are obtained in the physical domain. These are also calculated numerically for a magnesium crystal-like material and depicted through graphs to observe the variations of the considered physical quantities. The present study is useful and valuable for the analysis of problems involving mechanical shock, rotational speed, nonlocal parameter, temperature-dependent properties and elastic deformation.

This paper aims to select a type of mordant from aluminium salts, namely, aluminium sulphate, aluminium nitrate and polyaluminium chloride (PAC) with the lowest potential for contamination so that their use will minimise pollution from natural dye waste. It also aims to determine the pollution value of natural dye immersion waste from jackfruit wood extract, secang wood, mangsi fruit and several synthetic dyes, to identify potential environmental pollution.

Dyeing with natural dyes was performed by exhaust at room temperature by the pre-mordant method, while with synthetic dyes it was performed by exhaust according to the dyeing procedure (reactive, vat and naphthol). The groundwater, mordant solutions, natural dye extract and the waste-water from the natural and synthetic dyes were then tested to determine their biological oxygen demand (BOD₅), chemical oxygen demand (COD), total suspended solids (TSS), pH, Al and heavy metal contents such as chromium (Cr), copper (Cu), cadmium (Cd), nickel (Ni), cobalt (Co) and lead (Pb).

Aluminium sulphate had the lowest pollution load while PAC had the highest, as aluminium sulphate had a higher BOD₅/COD ratio (0.62–0.67) than aluminium nitrate (0.56–0.64) or PAC (0.44–0.54). The dyeing waste from the three natural dyes contained an acidic pH of 3.5–4.2, Al of 75.280–621.34 mg/L, Cr of 0.154–0.215 mg/L and Cu of 0.035–0.072 mg/L. The values of TSS, COD and BOD₅ are higher than the quality standards of the waste but are environmentally friendly because the ratio of the BOD₅/COD values from the waste ranges from 0.44–0.67.

The findings indicate that as a mordant, aluminium sulphate results in lower pollution loads than aluminium nitrate and PAC. However, all three mordants contain Cr and Cu, albeit in negligible concentrations. Therefore, it is recommended that future studies strive to identify a mordant that has lower pollution loads and does not contain metals but can increase dyeing results to satisfy consumer requirements. It is the hope that, with the discovery of a new mordant, natural dyes will be the solution for the heavy metal pollution caused by synthetic dyes.

The use of environmentally-friendly mordants and natural dyes in the Indonesian textile and batik industry will give rise to superior quality eco-textile and eco-batik products. Such environmentally-friendly and high-quality products will not only increase competition and consumer interest but increase product sales as well which will, in turn, increase incomes and the economy. Additionally, an increase in the use of natural dyes by the textile and batik industry will serve as additional income to the communities and farmers from which the raw materials for the natural dyes are sourced thereby creating jobs and increasing welfare.

As environmentally-friendly mordants and natural dyes replace the hazardous and toxic materials currently used in the textile and batik industry, it guarantees the health and safety of its consumers and workers. Furthermore, as the waste-water produced is biodegradable, it reduces river and groundwater pollution. It is, therefore, expected that this information will not only lead to a shift in attitude within the textile and batik industries but the adoption of environmentally-friendly materials, for the sake of the environment, as well as the development of eco-textile and eco-batik products.

Aluminium sulphate is a mordant type of aluminium salt with a lower potential for contamination than aluminium nitrate and PAC. However, PAC has been discovered to be a mordant for natural dyes, as has the fruit of the mangsi shrub, which has recently been discovered as a naturally occurring blue dye.

In the development of engine components a number of special techniques are used to combat the hostile operating environment which usually includes high and cyclic forces, high and cyclic temperatures, sliding and often corrosion and/or erosion. Examples of the use of these techniques, namely the development of special materials for substrate and surface, of mathematical modelling verified by telemetry, and of special machining, to solve the problems of the operating environment, are given in respect of piston rings, cylinder liners, bearings, camshafts and valve seat inserts. It is noted that of these techniques the development of special surface and substrate materials provides the most assistance. The application of materials technology to surface and substrate is illustrated with respect to ceramics, including silicon nitride, silicon carbide, zirconia and alumina. Applications underdevelopment include insulation, improvement of wear resistance, reduction of mass, increase of operating temperature and the reinforcement of metals, for example reinforcement of aluminium alloys using alumina fibres incorporated by squeeze casting. The several means open to improve the properties of gravity cast aluminium silicon alloys are reviewed and the improvement of properties obtained by squeeze casting without reinforcement are illustrated. The further enhancement of these properties by the design of an appropriate fibre reinforcement system, incorporated by squeeze casting, is then described. Its application to the reinforcement of a combustion bowl subject to high thermal stress is discussed and the performance of the resulting piston in relation to unreinforced pistons is described. In conclusion the market, product and process aspects of the development are correlated to demonstrate its overall value and to identify further applications.