Publications by authors named "Van Hai Le"

This study reports dicarboxylate cellulose nanofibrils (DCNF) as a novel reducing and supporting agent for producing silver nanoparticles (AgNPs) with high efficiency (63.82 % reduction) and loading (6.88 %) using UV light.

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Objectives: This study aims to investigate the effect of coating time on the formation of hydroxyapatite (HA) coating layer on ZK60 substrate and understand the biodegradation behavior of the coated alloy for biodegradable implant applications.

Methods: Biodegradable ZK60 alloy was coated by HA layer for different times of 0.5, 1, 2, and 4 h by chemical conversion method.

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This paper reports on multiple stage bleaching and its effect on the mechanical and swelling properties of compressed wood (CW). The natural wood specimen was bleached with NaClO in five steps and three hot-pressing conditions. Their effects were investigated in morphologies: lignin content, alpha-cellulose content, compression ratio, mechanical properties, swelling and, water contact angle.

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Transparent-wood (TW) is an emerging research topic that can be applied to biobased products. However, it is necessary to fill pores in TW with natural substances to prepare all-biobased TW. This paper reports an all-biobased TW by infiltrating cellulose nanofiber (CNF) and chitosan (CTS) suspensions into the bleached wood.

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Objectives: The aim of this study is to evaluate the effect of pH treatment on the formation of hydroxyapatite (HA) coating layer and the biodegradation rate of hydroxyapatite coated AZ31 alloy for applications in biodegradable implants.

Methods: HA was grown on the surface of AZ31 substrate at three different pH solutions of 7.5, 9.

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This paper reports the preparation, characterization and properties of synthetic melanin-like nanoparticle (MNP) reinforced chitosan nanocomposite films. The MNP was prepared using dopamine hydrochloride and sodium hydroxide which followed by spontaneous oxidation. The prepared MNP was spherical in shape and in the size range of ∼100 nm.

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While the demand for lightweight high-strength nanocomposites is immense, their progress has been severely limited due to inferior filler dispersion and filler-matrix interface adhesion. This article reports a novel modification of graphene oxide (GO) encapsulated by the copolymer of polydopamine (PD) and polyethylenimine (PEI) a Michael addition reaction, aiming to create robust ethylene vinyl acetate copolymer (EVA) nanocomposites even at very low amounts of filler loading by overcoming the above hindrances. It has been found that the addition of only 1.

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In this research, cellulose nanofiber (CNF) was isolated by the combination of chemical 2,2,6,6-tetramethylpiperidine-1-oxylradical (TEMPO)-oxidation and physical aqueous counter collision (ACC) methods The combination of TEMPO-oxidation and ACC is an efficient method to isolate CNFs by reducing chemical usage in TEMPO-oxidation and saving energy in ACC along with controlling the size of CNFs. Two cellulose sources, hardwood bleached kraft pulp (HW) and softwood bleached kraft pulp (SW), were used for the CNF isolation with different TEMPO oxidation time and a defined number of ACC pass. The CNF properties were investigated and compared in term of morphology, crystallinity index, transparency and birefringence.

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Silica powder at nanoscale was obtained by heat treatment of Vietnamese rice husk following the sol-gel method. The rice husk ash (RHA) is synthesized using rice husk which was thermally treated at optimal condition at 600°C for 4 h. The silica from RHA was extracted using sodium hydroxide solution to produce a sodium silicate solution and then precipitated by adding H2SO4 at pH = 4 in the mixture of water/butanol with cationic presence.

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