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Surface Modification of the Ti-35Nb-7Zr-5Ta Bio Alloy by the PM-EDM Route

Hayyawi Ahmed Rabeea, Al-Ethari Haydar, Haleem Ali Hubi

Advances in Science and Technology. Research Journal

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2024

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Vol. 18, no 3

140--150

EN

One of the most attractive β-Ti alloys is Ti–35Nb–7Zr–5Ta wt% (TNZT) alloy, which has one of the minimal Young’s moduli among the β-Ti family (about 55 GPa) and contains no cytotoxic elements. On the other hand, β-type Ti alloys are susceptible to bacterial infection because they lack an antibacterial function and can get contaminated quickly after implantation, making surface modification a keyway to improve these alloys' antibacterial properties. A recently created technique called powder mixed-EDM can improve machining, mechanical, and biological properties at the same time. In this research, silver was added to the dielectric fluid during PM-EDM of Ti-35Nb-7Zr-5Ta wt% alloy prepared by powder metallurgy route. The surface composition, Brinell hardness, corrosion resistance, ion release, and antibacterial properties were evaluated for TNZT alloy before and after surface modification. The results show better hardness and corrosion resistance as well as lower ion release for the PM-EDMed specimen due to the presence of Ag, oxides, and carbides such as NbC, TiC, TiO2, ZrO2, and Nb2O5 that’s deposited and embedded as a hard phase in the recast layer of the machined surface. Also, the antibacterial property of the PM-EDMed specimen is effectively improved as silver is an antibiotic with a wide range, so it has favorable antibacterial properties for Gram-negative and Gram-positive bacteria.

2

Structure and Properties of Cationic Chitosan Derivative Modified Bombyx mori

Minghui Xiao, Wei Zhang, Xinlan Dai, Jinjie Zhou

Fibres & Textiles in Eastern Europe

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2023

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Vol. 31, no. 6

56--62

EN

Cationic modification of silk fabric can highly improve its antibacterial property, but cationic modification may change the microstructure of silk fiber, and further affect its properties, thus O-methyl acrylamide quaternary ammonium salt of chitosan (NMA-HTCC), which is a kind of strong cationic chitosan derivative, was used for the modification on Bombyx mori silk fiber. The combination structure between NMA-HTCC and silk fiber was characterized by FT-IR. The surface morphology and structure of silk fiber after being treated by NMA-HTCC were investigated by SEM and XPS analysis. The crystalline structure and thermal stability of silk fibers before and after being treated were determined by XRD and DSC analysis, respectively. Then the breaking strength, breaking elongation and antibacterial properties of the silk yarns were also determined. The results indicated that the NMA-HTCC modified silk fiber clearly showed two characteristic absorption peaks at 1535 cm-1 and 1670 cm-1 due to the N-H bending and C=O stretch of the secondary amide in the acrylamidomethyl group of the NMA-HTCC molecule. The successful combination of NMA-HTCC and silk fiber was also confirmed by XPS and SEM analysis. Compared with the untreated silk sample, the diffracted intensity of the characteristic absorption peak and crystallinity of the NMA-HTCC modified silk fiber were both increased; the internal aggregation structure of the silk fiber treated with NMA-HTCC was much closer and its thermal stability was enhanced obviously. The breaking strength and elongation of silk fibers after being treated with NMA-HTCC were also significantly increased. Silk fibers treated with NMA-HTCC had excellent durable antibacterial properties against S. aureus and E. coli, even after 50 repeated launderings, with the bacterial reduction rate of the silk fibers maintained at over 95 %. The results in this research can provide the theoretical basis for the application of NMA-HTCC in the modifications of silk fabric.

3

Herbal Extract-Induced Silver Nanoparticles for Antibacterial Cotton Fabric

Rajput Sanjeev Kumar, Singh Mukesh Kumar, Shakyawar Dinesh Babu

Fibres & Textiles in Eastern Europe

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2023

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Vol. 31, no. 3

22--29

EN

Herbal extract-induced metallic nanoparticles have replaced the traditionally synthesized nanoparticles to achieve sustainability in antimicrobial textiles. Silver nanoparticles (NPs) were created by the bio-reducion of silver nitrate with eucalyptus corymbia leaf extract. The bi-lateral activities of herbal extract, like the reduction and capping of silver nanoparticles, have added new dimensions in the bactericidal sector. Silver nanoparticles were characterized by UV-visible spectroscopy, a particle size analyzer, Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), energy dispersive X-ray (EDX) and X-ray diffractometry. In this study these biosynthesized nanoparticles were applied on cotton fabric alone and along with chitosan by the pad-dry-cure method to create antibacterial clothing. Antibacterial efficiency was characterized using the colony counting method (serial dilution method). The treated fabric shows excellent antibacterial efficiency.

4

Silver-clay nanohybrid as a coating for improvement of the antibacterial properties of paper

Alikhah Tahereh, Babavand Arash, Afra Elyas, Ghasemian Ali, Saraeian Ahmadreza

Drewno : prace naukowe, doniesienia, komunikaty

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2020

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vol. 63, nr 205

109--124

EN

This comparative study was carried out to investigate the effect of nanosilver, silver-clay nanohybrid, and silver-milled clay nanohybrid coatings on the antibacterial characteristics of paper. Nanosilver (25 ppm) was used as a singleand double-layer coating. The results demonstrated that treatment with pure nanosilver was more efficient in the reduction of microbial growth. Also, milling of clay enabled better maintenance of silver nanoparticles, and led to a greater decrease in bacterial growth than in the case of the original silver-clay nanohybrid. Evaluation of the sustainability of antibacterial characteristics confirmed that, although pure nanosilver treatment achieved better performance in the first 15 minutes than nanohybrid samples, the performance of the nanohybrids improved with the passing of time. As expected, the treatments decreased the brightness of paper, while the opacity increased significantly; pure nanosilver treatment led to lower brightness than the others, and the opacity was higher in the case of the silver-clay nanohybrid than with the other treatments.

5

Plasma Grafting with Methyl Di-Ally Ammonium Salt to Impart Anti-Bacterial Properties to Polypropylene

Yao W.-H., Tsou C.-H., Chen J.-C.

Fibres & Textiles in Eastern Europe

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2016

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Vol. 24, no. 3 (117)

117--123

EN

Quaternary methyl di-ally ammonium salt (MDAA) was grafted on the surface of a polypropylene (PP) nonwoven using a low-temperature radio frequency discharge plasma. The graft ratio of MDAA to PP increased with the grafting temperature; at low grafting temperatures (30 or 60 °C), the graft ratio increased with the H2SO4 catalyst concentration, but at a high grafting temperature (80 °C), it was not affected, even without the use of an acid catalyst. The finished PP nonwoven exhibited excellent antibacterial activities toward Staphylococcus aureus, suggesting that plasma grafting is an effective method.

PL

Czwartorzędową solą metylodialliloamoniową (MDAA) szczepiono powierzchnię włókniny polipropylenowej stosując niskotemperaturową plazmę o częstotliwości radiowej. Stosunek szczepienia MDAA do PP wzrastał ze wzrostem temperatury szczepienia, przy niskich temperaturach szczepienia (30 lub 60°C) stosunek szczepienia wzrastał ze wzrostem stężenia katalizatora H2SO4, natomiast przy wysokich temperaturach szczepienia (80°C) nie zaobserwowano wpływu nawet bez stosowania kwasowego katalizatora. Wykończone włókniny polipropylenowe wykazywały doskonałą aktywność anytbakteryjną w stosunku do Staphylococcus aureus. Wyniki badań wskazują, że szczepienie plazmowe jest efektywną metodą uzyskiwania właściwości anytbakteryjnych.

6

Antimicrobial properties of flax fibers in the enzyme retting process

Tian Y., Liu X., Zheng X., Wang L.

Fibres & Textiles in Eastern Europe

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2016

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Vol. 24, no. 1 (115)

15--17

EN

“GB/T 20944.3-2008--Part 3: Shake flask method” was applied to assess the antimicrobial property of flax fibres. The antimicrobial efficiency of flax fibre was represented as the absolute antimicrobial rate and relative antimicrobial rate. Cotton fibre served as a contrast in relation to the antimicrobial rate. The retted flax fibre showed an absolute antimicrobial rate against E.coli and S. aureus, but only presented a relative antimicrobial rate against S. cerevisiae. The contents of pectic substances of flax straw such as cerolipoid, hydrotrope, pectin, hemicellulose and lignin declined during flax retting, especially lignin, whose content declined from 24% to 7.13%, and gaps appeared between the fibre bundles. Consequently the antimicrobial efficiency of flax fibre decreased gradually. This experiment confirmed the existence of antibacterial substances, but exactly what compounds associated with flax exhibiting antimicrobial properties is not discussed.

PL

Właściwości antybakteryjne włókien lnianych badano zgodnie z normą GB/T20944.32008: Właściwości oceniano poprzez bezwzględną i względną antybakteryjną intensywność. Włókna bawełniane służyły jako materiał porównawczy przy ocenianiu antybakteryjnej intensywności względnej. Roszone włókna lnu wykazywały bezwzględną intensywność antybakteryjną przeciwko E. coli i S. aureus, ale tylko względną intensywność antybakteryjną przeciwko S. cerevisiae. Zawartość substancji pektynowych w słomie lnianej, takich jak cerolipoidy, hydrotopy, pektyny, chemiceluloza, i ligniny zmniejszała się podczas roszenia. Szczególnie zmniejszyła się zawartość lignin spadając z 24% do 7,13%. W czasie roszenia pojawiały się szczeliny pomiędzy wiązkami włókien. W konsekwencji zdolności antybakteryjne włókien lnianych ulegały systematycznej degradacji. Przeprowadzony eksperyment potwierdził istnienie antybakteryjnych substancji ale nie stwierdzono, które składniki były najbardziej aktywne antybakteryjnie.

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Antibacterial Activity of PLA Fibres Estimated by Quantitative Methods

Kaźmierczak D., Guzińska K., Dymel M.

Fibres & Textiles in Eastern Europe

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2016

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Vol. 24, no. 2 (116)

126--130

EN

PLA fibres with the addition of the microbicidal agent Sanitized were examined by the two quantitative standards JIS L 1902:2002 and ASTM: E2149–01. It was found that the two different methods used to assess the antibacterial activity of one sample may produce results that contrast with each other. The impact of the testing conditions upon the results obtained was deliberated. Discussed are criteria to interpret the results obtained by the use of the two methods. The antibacterial activity of lactic acid liberated from PLA in an aqueous medium was confirmed. It was also examined how the laundering of fibers affect the antibacterial activity of the samples tested.

PL

Przedstawiono wyniki badania włókien, wykonanych z poli(kwasu mlekowego) z dodatkiem środka bójczego Sanitized, dwoma metodami ilościowymi według norm JIS L 1 902:2002 i ASTM: E2149–01:2010. Wykazano, że rozbieżność otrzymanych wyników powstała jako rezultat różnic w zastosowanych metodykach. Omówiono kryteria oceny wyników w obu normach. Potwierdzono antybakteryjne działanie kwasu mlekowego.