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Medical textile is one aspect of technical textiles and it is classified according to performance and functional properties for hygienic and healthcare products. Seaweeds have curative powers for curing most degenerative diseases. The paper aims to discuss these issues.

The present study focusses on the extraction of dyes from five seaweeds such as Ulva reticulata, Ulva lactuca, Sargassum wightii, Padina tetrastomatica and Acanthophora spicefera. The presence of bioactive compounds, antioxidant and antimicrobial properties of dye extracted from seaweeds was analysed. The dye extracted from green seaweed was applied on cotton fabric to obtain antimicrobial and other properties used to make non- implantable materials.

A maximum antioxidant inhibition percentage of 86.48+2.84 and a maximum antibacterial activity of 27 mm inhibition zone were obtained on the fabric treated with the dye extract from the Ulva lactuca seaweed. The physical properties such as tensile strength and tearing strength did not show much significant difference in untreated and treated fabric. The air permeability, water absorbency and wicking behaviour of treated fabric were reduced compared with untreated fabric. The washing and rubbing properties of treated fabric were very good after repeated washing.

This bioactive fabric has been used for non-implantable materials such as wound healing, face mask, surgical gowns and hygienic textiles in recent years.

The purpose of this paper is to investigate the efficient exploitation of bioactive compounds present in red, green and brown seaweeds to develop hygienic products.

To analyse the antioxidant properties and identification of significant bioactive compounds of green, red and brown seaweed treated cotton fabrics, total antioxidant activity, DPPH Free radical scavenging activity and gas chromatography-mass spectrometry analysis were used.

The experimental result specifies that the maximum antioxidant activity of 126.50 µg/ml and inhibition percentage of 76 ± 0.15 percent was achieved in the seaweed treated cotton fabrics. All six seaweed treated fabrics proved slightly lesser water vapour and air permeability compared with the untreated fabric.

The seaweed treated cotton materials are suitable for making wound dressing, surgical wear, face mask, sportswear, healthcare and hygienic applications.

The healthcare and hygiene textiles are gaining more importance for their eco-friendly and effective antimicrobial properties that have become essential to safeguard human beings from harmful microorganisms. The fabrics finished with chemical-based antimicrobial agents lead to environmental issues and are harmful to human beings. The paper aims to discuss these issues.

The present investigation is to develop a fabric with antioxidant and antimicrobial properties using the extracts of brown algae. Antimicrobial property has been imparted to the cotton fabric using microcapsules of brown seaweed extracts using the pad-dry-cure method. The presence of bioactive compounds and antioxidant activities of brown algae extracts was evaluated using gas chromatography-mass spectrometry and 2, 2-diphenyl-1-picrylhydrazyl radical scavenging technique, respectively. The total phenolic content of the seaweed extract was determined by the Folin-Ciocalteu method. The minimum bactericidal concentration and minimum inhibitory concentration methods were used to determine the antibacterial activity of the bacterial reduction percentage and parallel streak methods were used evaluate the antibacterial activity of seaweed-treated fabrics.

The methanol fraction of the treated fabric had the highest antioxidant activity (42.5+1.21 per cent), because the higher phenolic content traps the reactive oxygen species and develops the cells present in the skin. The results show that the lower inhibition (250 µg/mL) and bactericidal concentrations (1,000 µg/mL) possess higher antibacterial activity. The results also show that the treated fabric possess higher bacterial reduction of 96 per cent and higher zone of inhibition against Escherichia Coli and Staphylococcus Aureus which was about 35 mm and 40 mm. The air permeability, bending length and the wicking behaviour of the treated fabric were slightly reduced, but it has good bursting strength compared with the untreated fabric.

Such treated fabric is used for making wound dressing, surgical gowns, antibacterial socks and gauze bandage products in healthcare and hygiene textiles.

Medical textiles is a vibrant emerging field in the area of technical textiles and its category is based on its performance and biofunctional properties for hygienic and health care products. Biodegradable fabrics are widely used for medical textiles in recent years. Seaweeds provide a wide range of therapeutic possibilities for human beings both internally and externally due to the presence of bioactive compounds. The paper aims to discuss these issues.

This present study investigates the development of bioactive gauze fabric from Chaetomorpha linum seaweed/cotton blended fibres and also analysed the characteristics of Chaetomorpha linum seaweed/cotton blended gauze fabric and 100 per cent cotton gauze fabric. The effect of fibres on physical properties of fabric such as tensile strength, air permeability, wickability, water drop test and colour fastness properties were analysed. The antibacterial properties and antioxidant activity were assessed by DPPH radical scavenging, AATCC 100 and EN ISO 20645 test methods.

The experimental results indicate that the maximum antioxidant activity of 103.28±1.23 per cent inhibition was achieved at minimum concentration (500 µg/ml) of the blended fabric extract, and maximum antibacterial reduction of 95 per cent and zone of inhibition of about 26 mm were achieved in a blended fabric. The tensile strength, percentage of elongation and air permeability were more or less the same in both gauze fabrics. It is also found that Chaetomorpha linum seaweed/cotton blended gauze fabric exhibit better wickability and water absorbency properties than 100 per cent cotton gauze fabric. The colour fastness properties to washing and rubbing showed excellent results in the blended gauze fabric, and it is used for making wound dressing materials.

This bioactive gauze fabric was used for non-implantable materials such as wound healing, face mask, surgical gowns and hygienic textiles in recent years.

The purpose of this paper is to explore the synergic effect of wild turmeric (Curcuma Aromatica Salisb.) and holy basil (Ocimum Tenuiflorum L.) combination herbal extracts treatment on the moisture management properties of cotton, lyocell and micro-denier single jersey knitted fabrics and the factors affecting it, which is intended for the development of healthcare apparel products.

The pre-treated single jersey knitted fabrics of cotton, lyocell and micro-denier polyester fabrics were given finishing treatment with the wild turmeric (Curcuma Aromatica Salisb.) and holy basil (Ocimum Tenuiflorum L.) combination herbal extract proportions of 100%:0%, 75%:25%,50%:50%; 25%:75% and 0%:100%. The D-optimal factorial design developed using Design Expert software was used for the study. The finishing treatments were carried out using the pad−dry−cure method. The aim of the work is to find out the influence of combination herbal extract proportion, textile material and their interaction effect on the moisture management properties.

The ANOVA results revealed that the overall moisture management properties of single jersey knitted fabrics are influenced by the material type, combination herbal extract proportion and the interaction between material type and the combination herbal extracts proportion. The overall moisture management properties of combination herbal extracts treated cotton single jersey fabrics are found to be better than that of lyocell and micro-denier polyester fabrics due to their excellent accumulative one-way transport capability after the finishing treatment. Among the combination herbal extract proportions, 50:50 per cent combination herbal extract proportion was found to be better than other proportions.

The study on the moisture management properties of combination herbal extracts of wild turmeric (Curcuma Aromatica Salisb.) and holy basil (Ocimum Tenuiflorum L.) is a novel attempt to explore the synergic effect of active constituents in both the herbs.

The purpose of the paper is to study effect of the implantation of oxygen and helium ions on the corrosion performance of the AISI3l6L stainless steel. It presents useful new results which allows one to draw conclusions as to the suitability of the helium and oxygen ion implanted AISI 316L stainless steel for biomedical use in the body.

The implantation of oxygen and helium ions was done on AISI 316L SS at an energy level of 100 keV at a dose of 1×10¹⁷ ions/cm², at room temperature. In order to simulate the natural tissue environment, an electrochemical test using cyclic polarization was done in a 0.9 percent sodium chloride solution at a pH value of 6.3 at 37°C. This was carried out on both the virgin and implanted AISI 316L stainless steel for the purpose of comparing performance. In addition to this, the hardness of the virgin and implanted samples was also studied using Vickers microhardness tester with varying loads. Besides, the surface morphologies of the implanted samples and the corroded samples were studied with XRD and SEM.

From the study the following findings are made. First, the XRD and SEM results were found to be in accordance with the corrosion test results. Second, the general corrosion behavior showed a significant improvement in the case of both helium implanted (icorr=0.0689 mA/cm²) and oxygen implanted (icorr=1.104 mA/cm²), when compared to the virgin AISI 316L SS (icorr=1.2187 mA/cm²). The pitting corrosion showed a significant improvement for helium implanted (Epit=230 mV) when compared to virgin material (Epit=92 mV). The oxygen implanted has not shown any improvement (Epit=92 mV). The surface hardness is found to be 1202 HV for helium implanted and 1020 HV for oxygen implanted, while it is found to be 195 HV for the virgin material. The hardness of the helium and oxygen implanted samples is found to be increased by about 600 percent and 500 percent, respectively, when compared to the virgin samples. Helium implanted samples show better performance in terms of corrosion resistance and hardness when compared to those of the oxygen implanted samples.

Although a number of authors have conducted many research on AISI 316L stainless steel, this work has original experimental results in terms of the oxygen and helium ion implantation parameters used and the specific tests: microhardness, electrochemical corrosion test, SEM and XRD that were used. It thus presents useful new results which allows one to draw conclusions as to the suitability of the Helium and Oxygen ion implanted AISI 316L stainless steel for biomedical use.

Parts that are to be used in aircraft, satellites, automobiles and ships should have sound microstructure. Components made from AA6082/Si₃N₄ and AA6082/SiC composites are in demand from industries. Hence, these components are to be fabricated by suitable technique at the appropriate value of process parameters. The purpose of this paper is Microstructure analysis of AA6082/Si3N4 and AA6082/SiC composites

AA6082/Si₃N₄ and AA6082/SiC composites are successfully fabricated using the stir casting process. Their microstructures have been analyzed. This has been done at different magnification. The effect of the addition of Si₃N₄ and SiC particles in the 6082 aluminum alloy is investigated. Microstructure of AA6082/Si₃N₄ and AA6082/SiC composites are also compared. Results show that Si₃N₄ and SiC particles have good wettability with AA6082. These reinforcement particles are homogeneously distributed in the matrix of AA6082.

There are no adverse effects of reactions in the microstructure of AA6082/Si₃N₄ and AA6082/SiC composites. There is not much difference between the distribution and interfacial characteristics of Si₃N₄ and SiC particles. AA6082/Si₃N₄ and AA6082/SiC composites have good properties. This is high strength at low density. Due to which they become suitable for the aircraft and space industry. So far, SiC, Al₂O₃ and tungsten carbide have been mostly used as reinforcements with different grades of aluminum alloy.

Not much experimental work is found with Si₃N₄ and SiC particles as reinforcement with AA6082. The novelty of this research work is that an effort has been made to fabricate AA6082/Si₃N₄ and AA6082/SiC composites at such values of process parameters, by stir casting process, so that sound and defect free microstructure is obtained. Microstructure of AA6082/Si₃N₄ and AA6082/SiC composites is also compared, to find which is better.

The purpose of this paper is to develop an organized structure for damage detection of a cracked cantilever beam using finite element method and experimental method technique.

Due to presence of cracks the dynamic characteristics of structure change. The change in dynamic behavior has been used as one of the criteria of fault diagnosis for structures. Major characteristics of the structure which undergo change due to presence of crack are: natural frequencies, the amplitude responses due to vibration and the mode shapes. Therefore, an attempt has been made to formulate a smart technique for minimizing the amplitude of vibration for crack cantilever beam structures. In the analysis both single and double cracks are taken into account.

The results of the active vibration control experiments proved that piezoelectric sensor/actuator pair is an effective sensor and actuator configuration for active vibration control to reduce the amplitude of vibration for closed-loop system.

It is necessary that structures must safely work during its service life, but damages initiate a breakdown period on the structures which directly affect the industrial growth. It is a recognized fact that dynamic behavior of structures changes due to presence of crack. It has been observed that the presence of cracks in structures or in machine members leads to operational problem as well as premature failure.

Casting is one of the well-known manufacturing processes to make durable parts of goods and machinery. However, the quality of the casting parts depends on the proper choice of process variables related to properties of the materials used in making a mold and the product itself; hence, variables related to product/process designs are taken into consideration. Understanding casting techniques considering significant process variables is critical to achieving better quality castings and helps to improve the productivity of the casting processes. This study aims to understand the computational models developed for achieving better quality castings using various casting techniques.

A systematic literature review is conducted in the field of casting considering the period 2000–2020. The keyword co-occurrence network and word cloud from the bibliometric analysis and text mining of the articles reveal that optimization and simulation models are extensively developed for various casting techniques, including sand casting, investment casting, die casting and squeeze casting, to improve quality aspects of the casting's product. This study further investigates the optimization and simulation models and has identified various process variables involved in each casting technique that are significantly affecting the outcomes of the processes in terms of defects, mechanical properties, yield, dimensional accuracy and emissions.

This study has drawn out the need for developing smart casting environments with data-driven modeling that will enable dynamic fine-tuning of the casting processes and help in achieving desired outcomes in today's competitive markets. This study highlights the possible technology interventions across the metal casting processes, which can further enhance the quality of the metal casting products and productivity of the casting processes, which show the future scope of this field.

This paper investigates the body of literature on the contributions of various researchers in producing high-quality casting parts and performs bibliometric analysis on the articles. However, research articles from high-quality journals are considered for the literature analysis in identifying the critical parameters influencing quality of metal castings.

The systematic literature review reveals the analytical models developed using simulation and optimization techniques and the important quality characteristics of the casting products. Further, the study also explores critical influencing parameters involved in every casting process that significantly affects the quality characteristics of the metal castings.

It is seen that little amount of work on optimization of mechanical properties taking into consideration the combined effect of design variables such as stacking angle, stacking sequence, different resins and thickness of composite laminates has been carried out. The focus of this research work is on the optimization of the design variables like stacking angle, stacking sequence, different resins and thickness of composite laminates which affect the mechanical properties of hybrid composites. For this purpose, the Taguchi technique and the method of gray relational analysis (GRA) are used to identify the optimum combination of design variables. In this case, the effect of the abovementioned design variables, particularly of the newly developed resin (NDR) on mechanical properties of hybrid composites has been investigated.

The Taguchi method is used for design of experiments and with gray relational grade (GRG) approach, the optimization is done.

From the experimental analysis and optimization study, it was seen that the NDR gives excellent bonding strength of fibers resulting in enhanced mechanical properties of hybrid composite laminates. With the GRA method, the initial setting (A3B2C4D2) was having GRG 0.866. It was increased by using a new optimum combination (A2B2C4D1) to 0.878. It means that there is an increment in the grade by 1.366%. Therefore, using the GRA approach of analysis, design variables have been successfully optimized to achieve enhanced mechanical properties of hybrid composite laminates.

This is an original research work.