Lignin-based flame retardant via sequential purification-nanoparticle formation, and NP coupled chemical modification.

A nonhalogenated and ecofriendly flame-retarding material was developed using lignin, one of the main components of lignocellulosic biopolymers. Lignin was purified, dissolved, and formulated as nanoparticles and implemented after processing in an ecofriendly water-based γ-valerolactone (GVL) system at different concentrations. Nitrogen‑phosphorus sequential chemical modification was performed using polyethyleneimine (PEI) and phytic acid (PA), The char residue increased by ≥10 % compared with lignin nanoparticles (LNPs).

Catalyst-recirculating system in steam explosion pretreatment for producing high-yield of xylooligosaccharides from oat husk.

We propose a closed-loop pretreatment process, wherein volatiles produced during steam explosion pretreatment were recovered and reintroduced as acid catalysts into the pretreatment system. The volatiles were separated through a drastic decompression process followed by a steam explosion process and recovered as a liquified catalyst (LFC) through a heat exchanger. The LFC effectively served as an acid catalyst for hemicellulose hydrolysis, significantly decreasing residence time from 90 min to 30 min to achieve 80 % conversion yield at 170 °C.

Effect of hemicellulose hydrolysate addition on the dehydration and redispersion characteristic of cellulose nanofibrils.

Nanocellulose, owing to its environmentally friendly and unique attributes, is gaining traction in various industries. However, commercialization of nanocellulose faces challenges due to structural alterations during drying process, leading to irreversible aggregation. This study, inspired by wood's natural structure, introduces a cellulose nanofibril (CNF) drying system using hemicellulose hydrolysate (HH) as a capping agent.

Glucaric Acid Production from via TEMPO-Mediated Oxidation with an Efficient Separation System.

In this study, production and isolation of glucaric acid from lignocellulosic biomass were performed via potassium cation-based TEMPO-mediated oxidation for the ease of glucaric acid isolation. To optimize the oxidation conditions, response surface methodology (RSM) was adopted using standard glucose as the raw material. Among the oxidation conditions, the dosage of oxidant and pH of reaction affected the glucaric acid production, and the optimum conditions were suggested by RSM analysis: 5 °C of reaction temperature, 4.

Lignin/PVA hydrogel with enhanced structural stability for cationic dye removal.

In this study, a lignin-based hydrogel for wastewater treatment was prepared by incorporating kraft lignin (KL) into a poly (vinyl alcohol) (PVA) matrix. The underwater structural stability of the KL-PVA hydrogel was guaranteed through physicochemical crosslinking, involving freeze-thaw process and chemical crosslinking reaction. The KL-PVA hydrogel displayed superior compressive characteristics compared to the original PVA hydrogel.

Efficacy of smartphone application-based multi-domain cognitive training in older adults without dementia.

Background: As the population ages and the prevalence of dementia increases, there is a growing emphasis on the importance of cognitive training to prevent dementia. A smartphone application-based cognitive training software program, BeauBrain Trainer (BBT), has been developed to provide better access to cognitive training for older adults. Numerous studies have revealed the effectiveness of cognitive training using a cognitive assessment tool.

Biodegradation behavior of acetylated lignin added polylactic acid under thermophilic composting conditions.

Acetylated lignin (AL) can improve compatibility with commercial plastic polymers compared to existing lignin and can be used as an effective additive for eco-friendly biocomposites. For this reason, AL can be effectively incorporated into polylactic acid (PLA)-based biocomposites, but its biodegradation properties have not been investigated. In this study, biodegradation experiments were performed under mesophilic and thermophilic conditions to determine the effect of AL addition on the biodegradation characteristics of PLA-based biocomposites.

Enhancement of elongation at break and UV-protective properties of poly(lactic acid) film with cationic ring opening polymerized (CROP)-lignin.

In this study, the intrinsic brittleness of poly(lactic acid) (PLA) was overcome by chemical modification using ethyl acetate-extracted lignin (EL) via cationic ring-opening polymerization (CROP). The CROP was conducted to promote homopolymerization under starvation of the initiator (oxyrane). This method resulted in the formation of lignin-based polyether (LPE).

Fabrication of transparent cellulose nanofibril composite film with smooth surface and ultraviolet blocking ability using hydrophilic lignin.

Ecofriendly multifunctional films with only biomass-based components have gathered significant interest from researchers as next-generation materials. Following this trend, a TEMPO-oxidized cellulose nanofibril (TOCNF) film containing hydrophilic lignin (CL) was fabricated. To produce the lignin, peracetic acid oxidation was carried out, leading to the introduction of carboxyl groups into the lignin structure.

Effect of chemically modified lignin addition on the physicochemical properties of PCL nanofibers.

In this study, a chemically modified lignin additive was successfully prepared to improve the physicochemical properties of biodegradable polycaprolactone (PCL)-based nanofibers. The molecular weight and surface functional group characteristics of lignin were effectively controlled through a solvent fractionation process using ethanol. Then, PCL-g-lignin was successfully synthesized by using ethanol-fractionated lignin as a platform for the PCL grafting process.

Physicochemical characteristics of lignin-g-PMMA/PLA blend via atom transfer radical polymerization depending on the structural difference of organosolv lignin.

Lignin has different structural characteristics depending on the extraction conditions. In this study, three types of ethanol organosolv lignin (EOL) were produced under different extraction conditions involving the reaction temperature (140, 160, 180 °C), sulfuric acid concentration (0.5, 1, 1.

Thermoplasticity reinforcement of ethanol organosolv lignin to improve compatibility in PLA-based ligno-bioplastics: Focusing on the structural characteristics of lignin.

Commonly, lignin macromolecules have limitations in application to the thermoplastics industries due to poor dispersibility and interfacial compatibility within ligno-bioplastics. In this study, the dispersibility and interfacial compatibility of ethanol organosolv lignin (EOL) in PLA-based ligno-bioplastic were improved by enhancing the thermoplasticity via oxypropylation. Further, three types of EOLs extracted from different severity conditions were applied to investigate the effect of the structural characteristics of EOLs on the changes in the thermal properties.

Eco-friendly alkaline lignin/cellulose nanofiber drying system for efficient redispersion behavior.

Although nanocellulose is an eco-friendly, high-performance raw material provided by nature, the agglomeration of nanocellulose that occurs during the drying process is the biggest obstacle to its advanced materialization and commercialization. In this study, a facile and simple nanocellulose drying system was designed using lignin, which is self-assembled together with cellulose in natural wood, as an eco-friendly additive. The addition of lignin not only minimized aggregation during the drying and dehydration process of nanocellulose but also ensured excellent redispersion kinetics and stability.

Cationic surface-modified regenerated nanocellulose hydrogel for efficient Cr(VI) remediation.

Because nanocellulose has a large specific surface area and abundant hydroxyl functional groups due to its unique nanomorphology, interest increases as an eco-friendly water treatment material. However, the distinctive properties of nanocellulose, which exists in a dispersion state, strongly hamper its usage in practical water treatment processes. Additionally, nanocellulose shows low performance in removing anionic pollutants because of its anionic characteristics.

NIR-chemometric approaches for evaluating carbonization characteristics of hydrothermally carbonized lignin.

The aim of this study is to establish prediction models for the non-destructive evaluation of the carbonization characteristics of lignin-derived hydrochars as a carbon material in real time. Hydrochars are produced via the hydrothermal carbonization of kraft lignins for 1-5 h in the temperature range of 175-250 °C, and as the reaction severity of hydrothermal carbonization increases, the hydrochar is converted to a more carbon-intensive structure. Principal component analysis using near-infrared spectra suggests that the spectral regions at 2132 and 2267 nm assigned to lignins and 1449 nm assigned to phenolic groups of lignins are informative bands that indicate the carbonization degree.

Phenolic Hydroxyl Groups in the Lignin Polymer Affect the Formation of Lignin Nanoparticles.

Alkaline soda lignin (AL) was sequentially fractionated into six fractions of different molecular size by means of solvent extraction and their phenolic hydroxyl groups were chemoselectively methylated to determine their effect on nanoparticle formation of lignin polymers. The effect of the lignin structure on the physical properties of nanoparticles was also clarified in this study. Nanoparticles were obtained from neat alkaline soda lignin (ALNP), solvent-extracted fractions (FALNPs, i.

Shape memory alloy-driven undulatory locomotion of a soft biomimetic ray robot.

The objective of this study was to imitate undulatory motion, which is a commonly observed swimming mechanism of rays, using a soft morphing actuator. To achieve the undulatory motion, an artificial muscle built with shape memory alloy-based soft actuators was exploited to control the shape-changing behavior of a soft fin membrane. Artificial undulating fins were divided into two categories according to the method of generating the wave motion: single and multiple actuator-driven fins.

Formation of pure nanoparticles with solvent-fractionated lignin polymers and evaluation of their biocompatibility.

This study aimed to determine the effects of lignin characteristics (mainly molecular weight, functional groups, and internal linkages) on nanoparticle formation. First, five different lignin fractions (M 1460-12,900) were obtained from commercial kraft lignin (KL) by sequential solvent extraction. Functional groups and internal linkages were determined in lignin fractions, each fraction consisting of different levels and ratios.

Evaluation of Xylooligosaccharides Production for a Specific Degree of Polymerization by Liquid Hot Water Treatment of Tropical Hardwood.

is known as attractive biomass, and it has been utilized for eucalyptus oil, furniture, and pulp and paper production that causes a significant amount of byproducts. Liquid hot water treatment depending on combined severity factor (CSF) was subjected to isolate hemicellulose fraction from and to produce xylooligosaccharides (XOS). The xylan extraction ratio based on the initial xylan content of the feedstock was maximized up to 77.

Thermal Properties of Ethanol Organosolv Lignin Depending on Its Structure.

In general, lignin exhibits unpredictable and nonuniform thermal properties due to the structural variations caused by the extraction processes. Therefore, a systematic understanding of the correlation between the extraction conditions, structural characteristics, and properties is indispensable for the commercial utilization of lignin. In this study, the effect of extraction conditions on the structural characteristics of ethanol organosolv lignin (EOL) was investigated by response surface methodology.

In vivo glucose metabolism and glutamate levels in mGluR5 knockout mice: a multimodal neuroimaging study using [F]FDG microPET and MRS.

Background: Perturbed functional coupling between the metabotropic glutamate receptor-5 (mGluR5) and N-methyl-D-aspartate (NMDA) receptor-mediated excitatory glutamatergic neurotransmission may contribute to the pathophysiology of psychiatric disorders such as schizophrenia. We aimed to establish the functional interaction between mGluR5 and NMDA receptors in brain of mice with genetic ablation of the mGluR5.

Methods: We first measured the brain glutamate levels with magnetic resonance spectroscopy (MRS) in mGluR5 knockout (KO) and wild-type (WT) mice.

Peracetic acid-induced kraft lignin solubilization and its characterization for selective production of macromolecular biopolymers.

This study was conducted to investigate the degradation characteristics of kraft lignin (KL) during peracetic acid (PAA) treatment, and to produce potentially valuable polymers of low molecular weight lignin by controlling the reaction conditions. For the peracetic acid treatment, acetic acid (AA) and hydrogen peroxide (HP) were directly mixed at ratios of 4:1, 1:1, and 1:4 (v/v) and employed as reaction media. After PAA treatment of kraft lignin at 80 °C, complete dissolution of the lignin and reduction in the molecular weight were observed.

A Low-Cost Vision-Based Monitoring of Computer Numerical Control (CNC) Machine Tools for Small and Medium-Sized Enterprises (SMEs).

In the new era of manufacturing with the Fourth Industrial Revolution, the smart factory is getting much attention as a solution for the factory of the future. Despite challenges in small and medium-sized enterprises (SMEs), such as short-term strategies and labor-intensive with limited resources, they have to improve productivity and stay competitive by adopting smart factory technologies. This study presents a novel monitoring approach for SMEs, KEM (keep an eye on your machine), and using a low-cost vision, such as a webcam and open-source technologies.

Pretreatment of bio-oil with ion exchange resin to improve fuel quality and reduce char during hydrodeoxygenation upgrading with Pt/C.

To obtain high-quality biofuel, bio-oil obtained from fast pyrolysis of woody biomass was pretreated with ion exchange resin (amberlyst 36) at 50°C, 100°C, and 150°C, and then the recovered liquid product was upgraded using hydrodeoxygenation (HDO) with Pt/C at 300°C. After the two-stage upgrading, 4 types of products (gas, light oil, heavy oil, and char) were obtained. Two-immiscible liquid products were consisted of organic heavy oil, derived from bio-oil, and aqueous light oil, based on the ethanol.