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991.
Journal of Mechanical Science and Technology - Pressure and viscous drags acting on a bubble rising in a viscous fluid are numerically estimated to obtain the corresponding drag coefficients that... 相似文献
992.
Paul Mathieu Rémi Bascou Francisco Sebastian Navarro Oliva Alla Nesterenko Anh-Tu Ngo Isabelle Lisiecki Erwann Guénin Fahmi Bedoui 《Polymer Engineering and Science》2023,63(3):830-840
We report the feasibility of electrospinning of protein-polymer multilayered scaffolds with selected materials such as non-hydrolyzed silk sericin (SS), polyethylene oxide (PEO), and polylactic acid (PLA), with tuned fiber size and properties for each layer. We present a new innovative way for the electrospinning (ES) of non-hydrolyzed SS mixed with PEO yielding fibers with an average diameter ranging between 120 and 150 nm. Different SS:PEO ratios have been electrospun to study the effect of the concentration of SS protein on the fibers size and shape, as well and their electrospinnability. Electrospun SS:PEO fibers display weak to no mechanical resistance (non-measurable) and their deposition onto a sturdier scaffold is necessary to allow their use in biomedical and/or pharmaceutical fields. Therefore, bilayer scaffolds have been fabricated consisting of a PLA support and SS:PEO fibers obtained from the optimized SS:PEO ratio (1.2:4). They are composed of a sturdy hydrophobic layer of PLA fibers and a layer of sticky hydrophilic SS:PEO fibers. The scaffolds have been characterized extensively by Fourier transforms infra-red (FTIR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), and their resistance to mechanical stress. Finally, hydrophobicity of both layers has been determined by measuring the contact angle of water droplets on the scaffolds, further proving the bilayer nature of the scaffolds. 相似文献
993.
Jianwei Zhang Kun Huang Xuetong Fan Gary D. Strahan Alberto Nuńez Majher I. Sarker Helen Ngo 《European Journal of Lipid Science and Technology》2023,125(11):2300012
Typically, short- and long-chain lipids from oils exhibit different antimicrobial activities and therefore have been used in agriculture and aquaculture, biomedical therapeutic and antibacterial fields. However, these fatty acids have limitations in terms of bioactive efficacy, thermostability and aqueous solubility. In this study, water-soluble iso-fatty acid arginate hydrochloride derivatives with antimicrobial properties were produced by introducing branched (iso-) chain and other linear- (n-) chain fatty acids to the “arginine” amino acid molecule. The two-step synthetic route was straightforward and provided an efficient 88% and 76% product yields for ethyl n-oleoyl arginate hydrochloride and ethyl iso-oleoyl arginate hydrochloride, respectively. ATR-FT-IR, NMR, and LC-MS-Q-TOF techniques were used to thoroughly characterize and confirm the products. These arginate products had strong antimicrobial activities against Listeria innucua, a Gram-positive bacterium with minimum inhibitory concentrations and minimum bactericidal concentrations ranging from 1.8 µg mL−1 to 29.1 µg mL−1. Therefore, the study demonstrated the development of a novel class of antimicrobial compounds from iso-fatty acids and arginates. 相似文献
994.
Zhenping Wang Nasir Ali Tien Dat Ngo Hoseong Shin Sungwon Lee Won Jong Yoo 《Advanced functional materials》2023,33(28):2301651
Even though atomically thin 2D semiconductors have shown great potential for next-generation electronics, the low carrier mobility caused by poor metal–semiconductor contacts and the inherently high density of impurity scatterings remains a critical issue. Herein, high-mobility field-effect transistors (FETs) by introducing few-layer PdSe2 flakes as channels is achieved, via directly depositing semimetal antimony (Sb) as drain–source electrodes. The formation of clean and defect-free van der Waals (vdW) stackings at the Sb–PdSe2 heterointerfaces boosts the room temperature transport characteristics, including low contact resistance down to 0.55 kΩ µm, high on-current density reaching 96 µA µm−1, and high electron mobility of 383 cm2 V−1 s−1. Furthermore, metal–insulator transition (MIT) is observed in the PdSe2 FETs with and without hexagonal boron nitride (h–BN) as buffer layers. However, the layered h–BN/PdSe2 vdW stacking eliminates the interference of interfacial disorders, and thus the corresponding device exhibits a lower MIT crossing point, larger mobility exponent of γ ∼ 1.73, significantly decreased hopping parameter of T0, and ultrahigh electron mobility of 2,184 cm2 V−1 s−1 at 10 K. These findings are expected to be significant for developing high mobility 2D-based quantum devices. 相似文献