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1.
Heliyon ; 10(18): e37952, 2024 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-39328563

RESUMEN

Hydrogels are used in modern wound dressings due to their ability to provide comfort with quick healing. However, poor mechanical properties of hydrogels limit their availability in commercial wound dressings. Nonwovens are highly porous, strong, and flexible structures that can provide support to hydrogels without compromising their properties. In this study, a cost-effective and sustainable hydroentangled nonwoven from industrial cotton waste was prepared and incorporated into alginate hydrogel for wound dressings. The novel composite of hydroentangled cotton nonwoven and alginate hydrogel was synthesized by a simple sol-gel technique. The effect of concentration of alginate hydrogel (0.5 wt%, 1 wt%, 1.5 wt %) and drying temperature (20 °C, 40 °C, 60 °C) of composite was analyzed for high wound exudates. The properties of prepared composite samples were characterized by scanning electron microscopy (SEM), XRD, tensile strength, tear strength, Air permeability, moisture management wound exudate test, and quantitative antimicrobial testing. Moreover, the comfort performance of these samples was evaluated by air permeability and moisture management testing. The properties of developed composites are highly dependent on the concentration of alginate and drying temperature. The results showed that maximum fluid absorbency (%) of 650 was achieved with good comfort properties. This study can help to increase the commercial availability of hydrogel-based wound dressings.

2.
Int J Biol Macromol ; 278(Pt 1): 134630, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39142481

RESUMEN

Banana fibers are a sustainable material with natural mechanical strength and antibacterial properties. These fibers are extracted from the large amount of waste produced by banana pseudo stems annually. However, despite their numerous advantages, their stiffness and rough texture impede their full use in the textile. This research investigates the degumming treatment of banana fibers using enzyme combination and chemical methods to achieve spinnable soft banana fibers. An L9 orthogonal array was used in a Taguchi design of the experiment to optimize the process parameters. For enzyme combination degumming, the experimental setup comprised different quantities of hemicellulase, laccase, amylase, and pectinase; for chemical degumming, varied amounts of sodium hydroxide (NaOH) were used. The results indicate that enzyme-based degumming procedures produce better results than chemical treatments. Optimum enzyme combinations for various fiber qualities were found using the Taguchi design of experiments. These combinations included Hemicellulase 5 %, Laccase 5 %, Amylase 3 %, and Hemicellulase 5 %, Laccase 3 %, Pectinase 5 %. Without degrading the cellulose structure, these ideal enzyme combinations produced fibers with lower lignin content and higher cellulose percentages, moisture content, and tenacity values. By determining the most efficient enzyme combinations and their effects on fiber qualities, the study offers sustainable fiber processing methods for textile grade banana fiber.


Asunto(s)
Fibra de Algodón , Lacasa , Musa , Textiles , Musa/química , Lacasa/química , Lacasa/metabolismo , Poligalacturonasa/química , Poligalacturonasa/metabolismo , Amilasas/metabolismo , Amilasas/química , Glicósido Hidrolasas/metabolismo , Glicósido Hidrolasas/química , Celulosa/química
3.
Int J Biol Macromol ; 266(Pt 2): 131393, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38582476

RESUMEN

Biocomposites developed using natural fibers serve as a sustainable alternative to synthetic composite materials. However, narrowing the performance gap between synthetic composites and biocomposites requires serious efforts. A promising approach is the modification of natural fibers using various chemical treatments. This paper investigates the potential of tannic acid (TA) treatment as a sustainable approach to enhance mechanical performance and reduce moisture absorption of flax fabric-reinforced biocomposites. The methodology involves the treatment of flax woven fabric with tannic acid, a naturally occurring polyphenolic compound, followed by the fabrication of biocomposite using a green epoxy matrix. The variables studied during treatment are TA concentration and processing time. Characterization of untreated and treated flax fabric and its composites was done using various analytical techniques such as FTIR spectroscopy, moisture absorption and mechanical testing (tensile strength, flexural strength, and impact resistance). FTIR spectroscopy of TA-treated flax confirmed attachment of aromatic rings and carbon double bond formation, thus serving for properties enhancement. The mechanical characterization of composites showed that properties are enhanced up to an optimum limit of concentration and processing time i.e., 1 % concentration and 30 min of processing. Moisture absorption of the TA-treated composite also reduced significantly as compared to untreated composites. These findings contribute towards the advancement in sustainable biocomposites and pave the way for their utilization in various applications.


Asunto(s)
Lino , Polifenoles , Taninos , Resistencia a la Tracción , Textiles , Taninos/química , Lino/química , Espectroscopía Infrarroja por Transformada de Fourier , Fenómenos Mecánicos , Materiales Biocompatibles/química
4.
Environ Res ; 252(Pt 3): 118953, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38636643

RESUMEN

Gas separation membranes are critical in a variety of environmental research and industrial applications. These membranes are designed to selectively allow some gases to flow while blocking others, allowing for the separation and purification of gases for a variety of applications. Therefore, the demand for fast and energy-efficient gas separation techniques is of central interest for many chemical and energy production diligences due to the intensified levels of greenhouse and industrial gases. This encourages the researchers to innovate techniques for capturing and separating these gases, including membrane separation techniques. Polymeric membranes play a significant role in gas separations by capturing gases from the fuel combustion process, purifying chemical raw material used for plastic production, and isolating pure and noncombustible gases. Polyurethane-based membrane technology offers an excellent knack for gas separation applications and has also been considered more energy-efficient than conventional phase change separation methodologies. This review article reveals a thorough delineation of the current developments and efforts made for PU membranes. It further explains its uses for the separation of valuable gases such as carbon dioxide (CO2), hydrogen (H2), nitrogen (N2), methane (CH4), or a mixture of gases from a variety of gas spillages. Polyurethane (PU) is an excellent choice of material and a leading candidate for producing gas-separating membranes because of its outstanding chemical chemistry, good mechanical abilities, higher permeability, and variable microstructure. The presence of PU improves several characteristics of gas-separating membranes. Selectivity and separation efficiency of PU-centered membranes are enhanced through modifications such as blending with other polymers, use of nanoparticles (silica, metal oxides, alumina, zeolite), and interpenetrating polymer networks (IPNs) formation. This manuscript critically analyzes the various gas transport methods and selection criteria for the fabrication of PU membranes. It also covers the challenges facing the development of PU-membrane-based separation procedures.


Asunto(s)
Gases , Membranas Artificiales , Poliuretanos , Poliuretanos/química , Gases/química , Contaminantes Atmosféricos/análisis , Contaminantes Atmosféricos/química
5.
ACS Omega ; 9(16): 17706-17725, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38680368

RESUMEN

Herein, this study was compiled to investigate a suitable solution for the fabrication and development of the multifunctional defense tent from previously reported research. The military always needs to protect their soldiers and equipment from detection. The advancement of infrared detection technology emphasizes the significance of infrared camouflage materials, reducing thermal emissions for various applications. Objects emit infrared radiation detectable by devices, making military targets easily identifiable. Infrared camouflage mitigates detection by lowering an object's infrared radiation, achieved by methods such as reducing surface temperature, which is crucial in designing military tents with infrared (IR) camouflage, considering water repellency and antibacterial features. Water repellency, as well as antimicrobial properties, in army tents is also important as they have to survive in different situations. All these problems should be addressed with the required properties; therefore, the authors try to introduce a new method from which multifunctional tents can be produced through economical, multifunctional, and sustainable materials that have IR protection, water repellency, ultraviolet (UV) protection, air filtration and permeability, and antimicrobial properties. There is still no tent that performs multiple functions at a time, even those functions that do not correlate with each other such as water repellency, IR protection, antimicrobial, and air permeability. So, a multifunctional tent could be the solution to all these problems having all the properties discussed above. In this study based on the literature review, authors concluded a method for the required tent for canvas fabric coated with zinc sulfide (ZnS), graphene oxide (GO), and zinc oxide (ZnO), or these materials should be incorporated in fiber formation because fiber composition has more impact. These multifunctional tents will be very beneficial due to their multifunctions like weather resistance, durability, and long life. These would help the army in their missions by concealing their soldiers and equipment from detection by cameras and providing filtered air inside the tent in case of gases or explosions. The proposed method will help to fulfill the stated and implied needs of customers.

6.
Int J Biol Macromol ; 256(Pt 1): 128422, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38013075

RESUMEN

Alginate hydrogel is highly efficient for water filtration due to its anti-fouling nature and formation of strong hydration membranes. However, poor mechanical properties of alginate hydrogel membrane limit its installation in water treatment. There is a need to enhance mechanical properties of alginate hydrogel membranes using eco-friendly, cost-effective materials and technologies. In this work, hydroentangled non-woven from cotton waste (comber noil) fibers was prepared. This non-woven was immersed in solution of sodium alginate (0.5 %, 1 %, 1.5 %) followed by dipping in calcium chloride solution which resulted in gel formation on and into cotton fibers. The successful formation of gel on non-woven fabric was confirmed through FTIR (Fourier transform infrared spectroscopy) and properties of this composite membrane were analyzed by SEM (Scanning electron microscopy), XRD (X-ray diffraction), DSC (Differential scanning calorimeter), water contact, water flux, oil-water filtration, air permeability, tensile strength, and porosity tests. The results showed that porosity of prepared hydrogel membranes decreased with increasing alginate concentration from 0.5 % to 1.5 % which resulted in decreased water permeation flux from 2655 h-1/m2 to 475 h-1/m2. The prepared membrane has separation efficiencies for the oil-water mixture in the range of 97.5 % to 99.5 %. Moreover, the developed samples also showed significant antibacterial activity as well as improved mechanical properties. The strength of the prepared membrane is in the range of 40 N to 80 N. The developed sodium alginate hydrogel-based non-woven membrane could have potential applications for commercial water filtration systems.


Asunto(s)
Alginatos , Hidrogeles , Hidrogeles/química , Alginatos/química , Espectroscopía Infrarroja por Transformada de Fourier , Cloruro de Calcio , Antibacterianos
7.
Heliyon ; 9(11): e21513, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37964854

RESUMEN

This study introduces an innovative chemical retting approach, systematically optimized via Grey relational analysis, to achieve jute fibers that exhibit desirable characteristics of softness, high tensile strength, and suitability for spinning, with a particular focus on their application in the apparel industry. In this study, the effect of alkali treatment (alkali concentration, temperature and duration of retting) on jute fiber's chemical composition and mechanical characteristics was investigated. Jute fibers were treated at three concentrations (5 %, 10 %, 15 %) of alkali, at three different temperature (30 °C, 60 °C, & 90 °C) and for three different retting duration (12 h, 24 h, & 36 h). The surface morphology and crystallinity of fibers were analyzed using optical microscopy, X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. The fiber linear density and mechanical characteristics were also tested. The multi-response optimization of all the factors and the responses was investigated using the Grey relational analysis. The results showed that the fiber surface morphology and crystallinity increase with an increase in alkali concentration, retting time, and temperature. Chemical retting treatment also improved the fiber linear density and tensile strength. The finest fibers which were obtained in this research had a linear density of 2.18 Tex with a tenacity of 53.02 cN/tex and elongation of 4.54 %. The spinnable jute fibers were achieved after this treatment with excellent characteristics.

8.
Polymers (Basel) ; 15(17)2023 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-37688139

RESUMEN

This study investigates the influence of silane-treated aluminum hydroxide on the mechanical performance of flame-retardant composites. These composites have potential applications for luggage bags, as a replacement for conventional plastics, offering more durability and lighter weight. Glass fabric was used as the reinforcement, while epoxy was used as the matrix material. To impart flame retardancy, aluminum hydroxide nanoparticles were used as fillers in different weight % age (5%, 10% and 15%). As these are inorganic particles and have compatibility issues with the matrix material, silane-coupling agents (Dynasylan® 6490 and Dynasylan Glymo) were used to treat these filler particles. Both the silane-coupling agents fraction used for treatment and the fillers fraction added to the composites were varied to determine the most optimum combination. The mechanical properties of the developed composites such as tensile, flexural, and short beam shear strength were investigated. The best results were exhibited by 10% aluminum hydroxide fillers treated with 1% (by weight) coupling agent (Dynasylan Glymo).

9.
Polymers (Basel) ; 15(13)2023 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-37447421

RESUMEN

Frequent washing of textiles poses a serious hazard to the ecosystem, owing to the discharge of harmful effluents and the release of microfibers. On one side, the harmful effluents from detergents are endangering marine biota, while on the other end, microplastics are observed even in breastfeeding milk. This work proposes the development of sunlight-driven cleaning and antibacterial comfort fabrics by immobilizing functionalized Zn-doped TiO2 nanoparticles. The research was implemented to limit the use of various detergents and chemicals for stain removal. A facile sol-gel method has opted for the fabrication of pristine and Zn-doped TiO2 nanoparticles at three different mole percentages of Zn. The nanoparticles were successfully functionalized and immobilized on cotton fabric using silane coupling agents via pad-dry-cure treatment. As-obtained fabrics were characterized by their surface morphologies, availability of chemical functionalities, and crystallinity. The sunlight-assisted degradation potential of as-functionalized fabrics was evaluated against selected pollutants (eight commercial dyes). The 95-98% degradation of dyes from the functionalized fabric surface was achieved within 3 h of sunlight exposure, estimated by color strength analysis with an equivalent exposition of bactericidal activities. The treated fabrics also preserved their comfort and mechanical properties. The radical trapping experiment was performed to confirm the key radicals responsible for dye degradation, and h+ ions were found to be the most influencing species. The reaction pathway followed the first order kinetic model with rate constant values of 0.0087 min-1 and 0.0131 min-1 for MB and MO dyes, respectively.

10.
Polymers (Basel) ; 15(2)2023 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-36679316

RESUMEN

In aerospace and automotive applications, composite materials are used as a major structural material along with metals. Composite-metal and metal-metal joining are very crucial in such structures. Adhesive bonding is commonly used for this purpose. Since such structures are exposed to varying temperatures and dynamic loads, it is essential to investigate the response of such joints under thermomechanical loading. Though various studies have been reported in the literature to assess the thermomechanical properties of composites, adhesives, and their joints, the effect of the surface treatment of metals and composites on the improvement in the thermomechanical behavior of the joints has not been reported. The metal and composite surfaces were modified using chemical etching techniques. The interaction between adhesives and adherends was studied using the DTMA technique in compression mode. Anodizing treatment on aluminum alloys improved the stiffness properties of metallic joints to 36% and decreased the damping to 23%, while chemical treatment on composite and metal adherends increased the stiffness of composite-metal joints to 34% and reduced the energy dissipation to 20%.

11.
Polymers (Basel) ; 14(21)2022 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-36365551

RESUMEN

Composites are macroscopic combinations of chemically dissimilar materials preferred for new high-tech applications where mechanical performance is an area of interest. Mechanical apprehensions chiefly include tensile, creep, and fatigue loadings; each loading comprises different modes. Fatigue is cyclic loading correlated with stress amplitude and the number of cycles while defining the performance of a material. Composite materials are subject to various modes of fatigue loading during service life. Such loadings cause micro invisible to severe visible damage affecting the material's performance. Mode I fatigue crack propagates via opening lamina governing a visible tear. Recently, there has been an increasing concern about finding new ways to reduce delamination failure, a life-reducing aspect of composites. This review focuses on mode I fatigue behaviours of various preforms and factors determining failures considering different reinforcements with respect to fibres and matrix failures. Numerical modelling methods for life prediction of composites while subjected to fatigue loading are reviewed. Testing techniques used to verify the fatigue performance of composite under mode I load are also given. Approaches for composites' life enhancement against mode I fatigue loading have also been summarized, which could aid in developing a well-rounded understanding of mode I fatigue behaviours of composites and thus help engineers to design composites with higher interlaminar strength.

12.
Polymers (Basel) ; 13(23)2021 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-34883602

RESUMEN

Hydrogels wound dressings have enormous advantages due to their ability to absorb high wound exudate, capacity to load drugs, and provide quick pain relief. The use of hydrogels as wound dressings in their original form is a considerable challenge, as these are difficult to apply on wounds without support. Therefore, the incorporation of polymeric hydrogels with a certain substrate is an emerging field of interest. The present study fabricated cellulose hydrogel using the sol-gel technique and reinforced it with nonwoven cotton for sustainable wound dressing application. The nonwoven cotton was immersed inside the prepared solution of cellulose and heated at 50 °C for 2 h to form cellulose hydrogel-nonwoven cotton composites and characterized for a range of properties. In addition, the prepared hydrogel composite was also loaded with titania particles to attain antibacterial properties. The Fourier transform infrared spectroscopy and scanning electron microscopy confirmed the formation of cellulose hydrogel layers inside the nonwoven cotton structure. The fabricated composite hydrogels showed good moisture management and air permeability, which are essential for comfortable wound healing. The wound exudate testing revealed that the fluid absorptive capacity of cellulose hydrogel nonwoven cotton composite was improved significantly in comparison to pure nonwoven cotton. The results reveal the successful hydrogel formation, having excellent absorbing, antimicrobial, and sustainable properties.

13.
J Parasitol ; 107(2): 295-303, 2021 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-33844841

RESUMEN

Anaplasmosis is a widespread vector-borne disease affecting dogs, and Anaplasma platys is the major etiological agent of the disease. The study examines anaplasmosis molecular prevalence, related risk factors, and alteration of hematological variables in Anaplasma-affected dogs. A total of 150 blood samples were collected from dogs in the district of Lahore, Pakistan. The samples were screened with PCR targeting the 16S rRNA gene of Anaplasma. Sequencing of samples that were found positive after performing PCR was conducted. A questionnaire was developed to collect epidemiological data on subject dogs, and the information was analyzed with a logistic regression model using SPSS. The current study revealed an 11.34% (17/150) prevalence of anaplasmosis in dogs based on PCR detection. Tick infestation, previous tick history, house hygiene, and tick control status were major risk factors linked with disease occurrence. Red blood cell count, packed cell volume, hemoglobin, and platelet count were decreased significantly (P < 0.05) in Anaplasma-infected dogs. Phylogenetically, the 2 isolates of the current study clustered together, and that cluster was very similar to A. platys isolates from India, Malaysia, and Thailand.


Asunto(s)
Anaplasma/clasificación , Anaplasma/genética , Anaplasmosis/epidemiología , Anaplasmosis/parasitología , Enfermedades de los Perros/epidemiología , Enfermedades de los Perros/parasitología , Anaplasma/aislamiento & purificación , Anaplasmosis/sangre , Animales , Análisis por Conglomerados , Enfermedades de los Perros/sangre , Perros , Electroforesis en Gel de Agar/veterinaria , Femenino , Modelos Logísticos , Masculino , Pakistán/epidemiología , Filogenia , Reacción en Cadena de la Polimerasa/veterinaria , Prevalencia , ARN Ribosómico 16S/genética , Factores de Riesgo , Estaciones del Año , Alineación de Secuencia , Encuestas y Cuestionarios
14.
Acta Trop ; 203: 105298, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31837314

RESUMEN

Balantidium coli (B. coli) is an emerging ciliated protozoan parasite of zoonotic importance which causes a disease balantidiasis in a variety of host species including pigs, camels, ruminants, equines and even human. This disease has a cosmopolitan distribution with high prevalence rates in tropical and sub-tropical areas of the world due to favorable geo-climatic conditions for the development and survival of the parasite in these regions. Main reservoir hosts for this pathogen are pigs and animals; acquire infection mainly by the ingestion of the food or water contaminated with the porcine feces. The infected animal manifests clinical signs of anorexia, dehydration, profuse watery diarrhea and retarded growth. Wet mount slide prepared from intestinal scrapings and fecal material is used for the identification of trophozoites and cysts stages of this parasite. PCR can also be used to confirm the parasite. Secnidazole, oxytetracycline and metronidazole have varying efficacy against B. coli infection in various domestic animal species. There is no comprehensive literature available on the occurrence and distribution of the infection at international level. Therefore, the published data between 1989 and 2019 regarding this disease is critically analyzed to provide a detailed overview on this pathogen with special emphasis on geographical distribution of B. coli in domestic animals and different therapeutic agents used to treat this infection. This review will pinpoint the endemic regions which may be a source of potential disease outbreaks and will also help in application of more effectual control strategies against balantidiasis.


Asunto(s)
Animales Domésticos/parasitología , Balantidiasis/veterinaria , Balantidium/aislamiento & purificación , Zoonosis/parasitología , Animales , Heces/parasitología
15.
J Therm Biol ; 78: 131-139, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30509629

RESUMEN

Worldwide, the effect of climatic variations has become a great challenge in poultry production. As global climate is changing, it alters the environmental temperatures, precipitation patterns and atmospheric carbon dioxide. Poultry farming mainly depends on climatic conditions such as temperature and humidity. Several factors can be involved but heat stress is one of most important environmental factor influencing a wide range of chickens performances including reduced feed intake which, in turn, affects growth rate, body weight, meat quality, egg quality, egg production, semen quality and fertility; these negative influences result in great economic losses. Heat stress associated food safety issues have gained special importance due to public awareness and an abundance of available scientific information. Environmental modifications (early heat conditioning, open sheds and cooling systems) and nutritional strategies (early feed restriction, electrolyte, vitamin and mineral balance) cannot satisfy the special needs of stressed poultry. Therefore, there exists a crucial need to explore effective strategies including genetic markers to enhance thermo-tolerance and productivity of poultry birds in hot regions of the world.


Asunto(s)
Crianza de Animales Domésticos/métodos , Respuesta al Choque Térmico , Enfermedades de las Aves de Corral/etiología , Aves de Corral/fisiología , Crianza de Animales Domésticos/normas , Animales , Enfermedades de las Aves de Corral/prevención & control , Productos Avícolas/normas
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