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1.
Heliyon ; 10(8): e29761, 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38681634

RESUMEN

Bast fibers are defined as those obtained from the outer cell layers of the bast of various plant families. They are finding use in textile applications and are widely used as reinforcements for green composites, as bast fibers are perceived as "sustainable". There is a growing demand for bast fibers across the world due to their renewable and biodegradable nature. The bast fibers are mainly composed of cellulose, which potentially considers the growing techniques, harvesting and extraction processes of bast fibers most used to produce fibers with appropriate quality to apply in the daily lives of modern men and women in contemporary society. This review paper looks at many aspects of natural fibers, with a focus on plant bast fibers, including their impact on prehistoric and historical society. This review shows that bast fibers are competitive compared to man-made fibers in many applications, but variability in mechanical properties and low tenacity may limit their use in high-strengthh composites and extend to, particularly in aerospace, automotive, packaging, building industries, insulation, E-composites (Eco composites), geotextiles and many other applications are currently being explored. Considering, important characteristics of bast fibers include physical, mechanical, and chemical properties. This makes bast fibers one of the most important classes of plant fibers to use as reinforcing agents in thermosetting/thermoplastic polymer matrices. And the effect of bast fibers as reinforcement in the properties of ECO-composites, GREEN-composites, BIO-composites, lightweight composites. Bast fibers play an important role in sustainability, the preservation of the health of the environment, the well-being of the next generation, and even the daily lives of men and women in the contemporary world.

2.
Heliyon ; 9(8): e18784, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37560668

RESUMEN

This article presents a study on the tensile properties of knitted fabrics commonly employed in polymeric matrix textile composites. The key mechanical parameters investigated include stress (Pa), strain, Young's modulus (Pa), and work of rupture (J). The knitted fabrics were developed using the Cixing Knitting System software and subsequently manufactured using a double jersey (electronic) flat knitting machine. The primary objective of this research was to explore the impact of various factors on the mechanical behavior of these knitted fabrics. The factors studied were wale and course directions, float stitch density, loop length (cm), and the type of synthetic knitting yarns used (100% polyester and 100% polyamide) along with different combinations of knitting yarns (100% cotton and 67% polyester/33% cotton hybrid). The adopted ASTM D 5034 standard, Response Surface Methodology (RSM), and Analysis of Variance (ANOVA) were employed to evaluate the mechanical performance of these fabric structures. The findings of the study revealed that the statistical adjustment of the data set for stress, strain, Young's modulus, and work of rupture in knitted fabric structures significantly reduced the standard deviations for mechanical responses. This information holds particular significance as it pertains to the frequent use of these knitted fabric structures as reinforcement in textile-reinforced composite materials. Overall, this study sheds light on the mechanical behavior in structures of knitted fabrics used in polymeric matrix composites, providing valuable insights for the design and optimization of advanced textile-based materials.

3.
Heliyon ; 9(8): e18805, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37576310

RESUMEN

Shear thickening fluids (STFs) refer to non-Newtonian fluids of the dilatant variety, wherein their viscosity experiences a significant surge with an escalation in the shear rate. In this investigative work, the friction behavior between yarns (pull-out) and absorption of static and kinetic energy during the phenomenon of friction between yarns in STFs are performed by monophase (MP-STF) adding nano SiO2 and dual-phase (MP-STF) adding carbon nanotubes. The ρ-Aramid fabrics were reinforced via the "foulard process", and carried out on MP-STF, and DP-STF/ρ-Aramid-impregnated fabrics to evaluate and compare with the enhancement in interfacial friction properties between yarns. The results showed that DP-STF has more significant than MP-STF and MP-STF in ultimate load, kinetic shear stress, static shear stress, and friction energy level effects. The DP-STF exhibits various friction enhancement mechanisms at the yarn interface, leading to higher absorption of static and kinetic energy related to interfacial friction, as indicated by the results obtained. Furthermore, the DP-STF/ρ-Aramid impregnated fabrics exhibited ultimate load (22.23 ± 0.522 N), kinetic shear stress (35.73 ± 0.850 MPa*100), static shear stress (36.28 ± 0.900 MPa*100), and friction energy level (610.33 ± 0.250). Increased ultimate load (581.7% and 180.7%), kinetic shear stress (621.4% and 174.6%), static shear stress (550.5% and 159.1%), and friction energy level (680.2 and 186.7%) compared to WT-STF and MP-STF, respectively. The current discoveries hold immense potential for various applications in the fields of engineering and smart material technologies. These applications span a multiplicity of industries, including sports products, medical advancements, space technology, as well as protective and shielding products.

4.
Foods ; 12(14)2023 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-37509803

RESUMEN

Given the substantial world coffee production, tons of coffee fruit cascara rich in bioactive compounds are discarded annually. Using this by-product to produce potentially healthy and acceptable foods is a sustainable practice that aggregates value to coffee production and may help improve people's lives. This study aimed to elaborate kombuchas from coffee cascara tea, evaluate their microbial profile, and monitor the changes in the volatile profile during fermentation, together with sensory attributes and acceptance by consumers from Rio de Janeiro (n = 113). Arabica coffee cascaras from Brazil and Nicaragua were used to make infusions, to which black tea kombucha, a Symbiotic Culture of Bacteria and Yeasts (SCOBY), and sucrose were added. Fermentation of plain black tea kombucha was also monitored for comparison. The volatile profile was analyzed after 0, 3, 6, and 9 days of fermentation via headspace solid phase microextraction GC-MS. A total of 81 compounds were identified considering all beverages, 59 in coffee cascara kombuchas and 59 in the black tea kombucha, with 37 common compounds for both. An increase mainly in acids and esters occurred during fermentation. Despite the similarity to black tea kombucha, some aldehydes, esters, alcohols, and ketones in coffee cascara kombucha were not identified in black tea kombucha. Potential impact compounds in CC were linalool, decanal, nonanal, octanal, dodecanal, ethanol, 2-ethylhexanol, ethyl acetate, ethyl butyrate, ethyl acetate, ß-damascenone, γ-nonalactone, linalool oxide, phenylethyl alcohol, geranyl acetone, phenylacetaldehyde, isoamyl alcohol, acetic acid, octanoic acid, isovaleric acid, ethyl isobutyrate, ethyl hexanoate, and limonene. The mean acceptance scores for cascara kombuchas varied between 5.7 ± 0.53 and 7.4 ± 0.53 on a nine-point hedonic scale, with coffee cascara from three-day Nicaragua kombucha showing the highest score, associated with sweetness and berry, honey, woody, and herbal aromas and flavors. The present results indicate that coffee cascara is a promising by-product for elaboration of fermented beverages, exhibiting exotic and singular fingerprinting that can be explored for applications in the food industry.

5.
Curr Microbiol ; 78(5): 1846-1855, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33861370

RESUMEN

Bovine mastitis is an infectious disease that affects the mammary gland of dairy cattle with considerable economic losses. Staphylococcus aureus is the main microorganism involved in this highly contagious process, and the treatment is only using antibiotics. Currently, the search for new treatment and/or compounds is still in need due to microbial resistance. In this work, we evaluated the potential of eugenol and thymol derivatives against S. aureus strains from bovine mastitis. On that purpose, nine derivatives were synthesized from eugenol and thymol (1-9), and tested against 15 strains of S. aureus from subclinical bovine mastitis. Initially, the strains were evaluated for the biofilm production profile, and those with strong adherence were selected to the antimicrobial sensitivity determination in the Minimum Inhibitory Concentration (MIC) assays. Herein the compounds toxicity was also evaluated by in silico analysis using Osiris DataWarrior® software. The results showed that 60% of the strains were considered strongly adherent and three strains (S. aureus 4271, 4745 and 4746) were selected for the MIC tests. Among the nine eugenol and thymol derivatives tested, four were active against the evaluated strains (MIC = 32 µg mL-1) within CLSI standard values. In silico analysis showed that all derivatives had cLopP < 5, cLogS > - 4 and TPSA < 140 Å2, and similar theoretical toxicity parameters to some antibiotics currently on the market. These molecules also showed negative drug-likeness values, pointing to the originality of these structures and theoretical feasibility on escaping of resistance mechanism and act against resistant strains. Thus, these eugenol derivatives may be considered as promising for the development of new treatments against bovine mastitis and future exploring on this purpose.


Asunto(s)
Mastitis Bovina , Infecciones Estafilocócicas , Animales , Antibacterianos/farmacología , Bovinos , Eugenol/farmacología , Femenino , Mastitis Bovina/tratamiento farmacológico , Pruebas de Sensibilidad Microbiana , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/veterinaria , Staphylococcus aureus , Timol/farmacología
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