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This paper aims to create and to study multifunctional shape memory polymer (SMP) composites having temperature-sensing and actuating capabilities by embedding thermochromic particles within the polymer matrix.

The multifunctional materials were fabricated following a process consisting of blending (of the thermochromic particles and the SMP at various ratios), mixing, degasing, moulding and thermal curing, prepared by incorporating thermochromic particles within the polymer. The effect of the thermochromic particles on the thermomechanical properties and thermally responsive shape memory effect of the resulting multifunction SMP composites were characterised and interpreted.

It was found that exposure of the composites to temperatures above 70°C led to a pronounced change of their colour that was recorded by the thermal and electrical actuation approaches and was reproducibly reversible. It was also found that the colour of the composites was independent of the mechanical state of the SMP. Such effects enabled monitoring of the onset of the set/release temperature of the SMP matrix. Furthermore, the combination of thermochromic additive and the SMP resulted in significantly improved thermomechanical strength, absorption of infrared radiation and the temperature distribution of the SMP composites.

The temperature-sensing and actuating capabilities of the polymeric shape memory composites developed through this study will help to extend the field of potential applications of such composites to fields including sensors, actuators, security labels and information dissemination, where colour indication is an advantageous feature.

The SMP composites capable of temperature sensing and actuating are novel.

Optimized plating conditions, included proper designs of insulating shield (IS), auxiliary cathode (AC) and different patterns, contribute to the uniformity enhancement of copper deposition.

Plating experiments were implemented in vertical continuous plating (VCP) line for manufacturing in different conditions. Multiphysics coupling simulation was brought to investigate and predict the plating uniformity improvement of copper pattern. In addition, the numerical model was based on VCP to approach the practical application.

With disproportionate current distribution, different plating pattern design formed diverse copper thickness distribution (CTD). IS and AC improved plating uniformity of copper pattern because of current redistribution. Moreover, optimized plating condition for effectively depositing more uniformed plating copper layer in varied pattern designs were derived by simulation and verified by plating experiment.

The comparison between experiment and simulation revealed that multiphysics coupling is an efficient, reliable and of course environment-friendly tool to perform research on the uniformity of pattern plating in manufacturing.

The purpose of this paper is to investigate cotton fabric behavior that is exposed to radar waves between selected operation frequencies as an alternative radar-absorbing material (RAM) response. Cotton fabric biocomposite materials were compared with carbon fabric composite materials, which are good absorbers, in terms of mechanical and electromagnetic (EM) properties for that purpose.

The laminated composite plates were manufactured by using a vacuum infusion process. The EM tests were experimentally performed with a vector network analyzer to measure reflection, transmission and absorption ability of cotton fabric, carbon fabric and cotton–carbon fabric (side by side) composite plates between 3 and 18 GHz. The tensile and low-velocity impact tests were carried out to compare the mechanical properties of cotton fabric and carbon fabric composite plates. A scanning electron microscope was used for viewing the topographical features of fracture surfaces.

The cotton fabric composite plate exhibits low mechanical values, but it gives higher EM wave absorption values than the carbon fabric composite plate in certain frequency ranges. Comparing the EM absorption properties of the combination of cotton and carbon composites with those of the carbon composite alone, it appears that the cotton–carbon combination can be considered as a better absorber than the carbon composite in a frequency range from 12 to 18 GHz at Ku band.

This paper shows how cotton, which is a natural and easily supplied low-cost raw material, can be evaluated as a RAM.

The purpose of this paper is to study the effect of alignment of conductive particles on the piezoresistivity of composite based on a theoretical model. The piezoresistivity of composite is associated with the characteristics of conductive network formed by the conductive particles distributed in the composite, which can be changed through aligning the conductive particles.

The orientations of the tunnel resistors formed by each two adjacent conductive particles are dependent on the aligned level of the conductive particles, and different orientations induce different deformations for a tunnel resistor under external strain, which determines the piezoresistivity of the composites. To investigate the resistance behavior of composites with various characteristics of conductive networks, a piezoresistivity model is developed in this paper by considering the aligned level of conductive particles.

The results obtained from the proposed piezoresistivity model indicate that the sensitivity and stability of composites can be enhanced through aligning the conductive particles. Also, the piezoresistivity of composites filled with randomly distributed conductive particles is isotropic, and it turns to be anisotropic when the conductive particles are aligned.

The change and its mechanism of the piezoresistivity upon the aligned level of conductive particles have been pointed out in this paper based on the proposed model. The achievement of this paper will help the people understand, predict and optimize the piezoresistivity of composites, and provide a new approach to design a strain sensor based on the piezoresistivity.

The aim of this study is to determine the fracture behavior of wool felt and fabric based epoxy composites and their responses to electromagnetic waves.

Notched and unnotched tensile tests of composites made of wool only and hybridized with a glass fiber layer were carried out, and fracture behavior and toughness at macro scale were determined. They were exposed to electromagnetic waves between 8 and 18 GHz frequencies using two horn antennas.

The keratin and lignin layer on the surface of the wool felt caused lower values to be obtained compared to the mechanical values given by pure epoxy. However, the use of wool felt in the symmetry layer of the laminated composite material provided higher mechanical values than the composite with glass fiber in the symmetry layer due to the mechanical interlocking it created. The use of wool in fabric form resulted in an increase in the modulus of elasticity, but no change in fracture toughness was observed. As a result of the electromagnetic analysis, it was also seen in the electromagnetic analysis that the transmittance of the materials was high, and the reflectance was low throughout the applied frequency range. Hence, it was concluded that all of the manufactured materials could be used as radome material over a wide band.

Sheep wool is an easy-to-supply and low-cost material. In this paper, it is presented that sheep wool can be evaluated as a biocomposite material and used for radome applications.

The combined evaluation of felt and fabric forms of a natural and inexpensive reinforcing element such as sheep wool and the combined evaluation of fracture mechanics and electromagnetic absorption properties will contribute to the evaluation of biocomposites in aviation.

This study aims to identify the bioactive compounds in the Onion (Allium burdickii [A.B]) bulb using Raman and Fourier transform infrared spectroscopy (FTIR) spectroscopy. It assessed the extraction conditions of bioactive compounds from A.B. while evaluating the best extraction conditions.

The research opted for an experimental qualitative approach. It examined the extraction conditions of A.B., namely, temperature (°C), time (min) and mass-to-liquor ratio (M:R) using ultraviolet-visible spectrophotometry. Identification of bioactive compounds present in the dye was performed using Raman spectroscopy and the validation of the results was done by FTIR spectroscopy.

The study determined the best extraction conditions (time, temperature, M:R) for A.B bulb. The study confirmed the presence of bioactive compounds.

The limitation was quantification of bioactive compounds in A.B bulb.

The findings prove that the A.B. bulb can provide a sustainable source of bioactive compounds (functionalized compounds). The study provides suitable extraction conditions for A.B. and further elaborates on the techniques for identifying bioactive compounds in A.B. bulb extracts.

The study provides A.B. as a source of bioactive compounds and a clean dye for textile coloration.

To the best of the authors’ knowledge, there is no documented study on the qualitative analysis of bioactive compounds in A.B using Raman and FTIR. Therefore, the study fulfils the identified need to ascertain alternative procedures for the analysis of bioactive compounds.

This research aimed to create inventive principles in managing quality and innovation systems that can be used as a guide for the development of effective innovation projects in hospitals.

Total quality and innovation management in healthcare (TQIM-H) framework and theory of inventive problem-solving (TRIZ) were integrated with results from in-depth interviews with 30 healthcare experts, resulting in TQIM-H inventive principle. The developed inventive principle was validated using 50 effective innovation projects from one of the largest healthcare conglomerates in Southeast Asia.

The TQIM-H inventive principle consisted of 7 dimensions and 72 procedures for creating innovation in hospitals under the medical quality framework. The principle effectively helps innovators develop innovative solutions that still strictly comply with medical guidelines.

Innovation is recognized as a critical factor that helps organizations adapt to global changes and increases the potential for competition, especially in hospitals. However, creating innovation in hospitals has a lower success rate than in other industries because, in general, ineffective innovation development strategies are used and the created innovation is not aligned with regulations and restrictions regarding healthcare quality in the healthcare system.

Denim fabric has become a wardrobe staple due to its versatility to be worn in a variety of fashions. This paper aims to study denim fabrics to understand their unique hand by developing a hand evaluation system using computational method. Also, the effect of various washes was studied on the hand and surface morphology of denim fabrics.

Five different denim samples were manufactured with various washing treatments. The Kawabata Evaluation System was used to measure the low stress mechanical properties. Computation method was used to develop hand equations using multiple regression technique in the MS Excel software. The correlation coefficient analysis was done to determine the authenticity of the developed equations. Five primary hand attributes such as softness, smoothness, fullness, flexibility and stretchability were shortlisted by a panel of judges that influence the fabric handle.

The correlation coefficient between subjective and computational total hand values with thermal properties and without thermal properties was 0.88 and 0.85, respectively. The enzymatic wash fabric has the highest total hand value followed by the acid, bleach and stone-washed fabrics.

Although the hand evaluation system is available for conventional textiles like suiting and shirting fabrics, the method to predict fabric hand of non-conventional textiles such as denim fabrics remains an unexplored topic. The stresses acting on denim fabrics are completely different. Therefore, to the best of the author’s knowledge, a novel attempt has been made in this research work to develop a computational model to predict the total hand value of denim fabrics.

This paper aims to evaluate the effects of banana (Musa) peel and guava (Psidium guajava) leaves extract as mordants on jute–cotton union fabrics dyed with onion skin extract as a natural dye.

The dye was extracted from the outer skin of onions by boiling in water and later concentrated. The bio-mordants were prepared by maceration using methanol and ethanol. The fabrics were pre-mordanted, simultaneously mordanted and post-mordanted with various concentrations according to the weight of the fabric. The dyed and mordanted fabrics were later subjected to measurement of color coordinates, color strength and colorfastness to the washing test. Furthermore, the dyed samples were characterized by Fourier transform infrared, and different chemical bonds were analyzed by X-ray photoelectron spectroscopy analysis.

Significant improvement was obtained in colorfastness and color strength values in various instances using banana peel and guava leaves as bio mordants. Post-mordanted with banana peel provided the best results for wash fastness. Better color strength was achieved by fabric post-mordanted with guava leave extracts.

Sustainable dyeing methods of natural dyes using banana peel and guava leaves as bio mordants were explored on jute–cotton union fabrics. Improvement in colorfastness and color strength for various instances was observed. Thus, this paper provides a promising alternative to metallic salt mordants.

The purpose of this paper is to prepare novel electroactive shape memory nanocomposites based on graphene and study the thermomechanical property and shape memory behavior of nanocomposites.

Graphene was dispersed in N,N-dimethylformamide, and the mixture was spooned into epoxy-cyanate ester mixtures to form graphene/epoxy-cyanate ester nanocomposites. The nanocomposites were deformed under 150°C, and shape recovery test was conducted under an electric voltage of 20-100 V.

Graphene is used to improve the shape recovery behavior and performance of shape-memory polymers (SMPs) for enhanced electrical actuation effectiveness. With increment of graphene content, the shape recovery speed of nanocomposites increases significantly.

A simple way for fabricating electro-activated SMP nanocomposites has been developed by using graphene.

The outcome of this study will help to fabricate the SMP nanocomposites with high electrical actuation effectiveness and improve the shape recovery speed of the nanocomposites.