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1.
Int J Biol Macromol ; 264(Pt 2): 130669, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38453110

RESUMO

This study aims to extract and characterize cellulose microfibers from cornhusk, an agricultural by-product. The extracted fibers will then be used as a reinforcing agent in a biocomposite made of thermoplastic corn starch. The process of extracting cellulose microfibers involved two treatments: sequential alkali treatment (using sodium hydroxide at 120 °C for 120 min) and peroxide bleach treatment (using hydrogen peroxide at 90 °C for 60 min). Various techniques such as Fourier transform infrared (FTIR), X-Ray diffraction (XRD), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA) were employed to characterize the extracted fibers. The properties of the composite were examined through tensile strength tests, contact angle measurements, and UV-Vis spectrophotometry. The study found that cellulose microfibers were successfully extracted from cornhusks, with a diameter of 7 to 30 µm and a crystallinity of 65 %. The treated fibers showed gradual degradation between 150 °C and 350 °C, indicating a lower amount of non-cellulosic substances compared to untreated cornhusks. Adding 10 % of the microfibers to the thermoplastic starch composite increased the tensile stress at breaking and the Young's modulus, but decreased the contact angle of water droplets and the film's transparency.


Assuntos
Celulose , Amido , Microscopia Eletrônica de Varredura , Água , Resistência à Tração
2.
J Environ Manage ; 268: 110688, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32383656

RESUMO

Natural oil sorbent materials with a high oil sorption capacity have recently received remarkable attention for oil spill cleanup from seawater. This study reports on the development of a superhydrophobic hollow cellulosic fiber that could serve as an oil spill cleanup material. As oil sorption is based on the physical and chemical characteristics of the sorbent, FTIR, SEM, XRD, and surface contact angle of the fibers were determined. A series of tests were then carried out to analyze the sorption capacity, dynamic oil retention, and reusability. Subsequently, the effect of the fibers' weight on the amount of oil absorption and absorption time was investigated. The wettability analyses showed that the milkweed floss fiber possessed a superhydrophobic characteristic (with the water contact angle of 140°). The empty channel of the fiber was more than 90% of its total volume. The hydrophobicity and capillary properties helped the fibers to absorb up to 100 g/g of oil, which was higher than that obtained by many natural cellulosic fibers.


Assuntos
Poluição por Petróleo , Poluentes Químicos da Água , Interações Hidrofóbicas e Hidrofílicas , Água
3.
Emerg Med J ; 32(6): 474-7, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25016389

RESUMO

OBJECTIVE: We compared the efficacy and safety of ultrasound-guided haematoma block with that of procedural sedation and analgesia in patients with acute distal radial fracture reduction pain control. METHODS: This was a randomised clinical trial on adult patients conducted in two teaching hospitals. Patients received intravenous midazolam plus fentanyl in the procedural sedation and analgesia group, and fracture site injection of lidocaine 10% in the ultrasound guided haematoma block group. We measured pain scores before reduction, during reduction and 5, 10 and 15 min after reduction by a numeric rating scale, and patient and physician satisfaction by a four-level Likert scale. Time to discharge, early adverse effects and late complications were also compared. RESULTS: We enrolled 160 patients with distal radial fracture and randomised 143 patients into two groups (after excluding 17 patients). Pain was effectively controlled in both groups. Pain scores had no statistically significant difference before and during reduction and 5 and 15 min after reduction in the procedural sedation and analgesia and ultrasound guided haematoma block groups. Patient and physician overall satisfaction were similar in the two groups. Time to discharge was significantly lower in the ultrasound guided haematoma block group. Four patients (5.5%) in the procedural sedation and analgesia group showed early adverse effects. No patient in either group showed any late complications. CONCLUSIONS: Ultrasound guided haematoma block may be a safe and effective alternative to procedural sedation and analgesia. TRIAL REGISTRATION NUMBER: 201112308104N5.


Assuntos
Anestésicos Locais/administração & dosagem , Lidocaína/administração & dosagem , Manipulação Ortopédica/efeitos adversos , Dor/prevenção & controle , Fraturas do Rádio/terapia , Ultrassonografia de Intervenção , Adulto , Anestesia Local , Feminino , Hematoma , Humanos , Masculino , Pessoa de Meia-Idade , Dor/etiologia , Estudos Prospectivos , Fraturas do Rádio/diagnóstico por imagem , Adulto Jovem
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