A5032859062- Advanced Cellulose Research Studies
- Lignin and Wood Chemistry
- Polysaccharides Composition and Applications
- Material Properties and Processing
- Particle physics theoretical and experimental studies
- earthquake and tectonic studies
- Quantum Chromodynamics and Particle Interactions
- High-Energy Particle Collisions Research
- Rheology and Fluid Dynamics Studies
- Earthquake and Tsunami Effects
- Geophysics and Gravity Measurements
- Seismology and Earthquake Studies
- Recycling and Waste Management Techniques
- Polysaccharides and Plant Cell Walls
- biodegradable polymer synthesis and properties
- Polymer Nanocomposites and Properties
- Pulsars and Gravitational Waves Research
- Textile materials and evaluations
- Liquid Crystal Research Advancements
- Polymer crystallization and properties
- Seismic Imaging and Inversion Techniques
- Electromagnetic wave absorption materials
- Coastal and Marine Dynamics
- Underwater Acoustics Research
- Carbon Nanotubes in Composites
Kyushu University
2008-2024
The Nakamura Hajime Eastern Institute
2020
Osaka University
1993-2019
National Institute for Land and Infrastructure Management
2014
The Ohio State University
2014
Kyoto University
2001-2013
Ryukoku University
2013
Port and Airport Research Institute
2009-2011
National Institutes of Natural Sciences
2006
National Astronomical Observatory of Japan
2005
The steady flow and the dynamic viscoelastic properties of cellulose fiber suspensions were investigated as functions suspension concentration shape using a parallel-plate type rheometer. Various concentrations made from various types fibers, i.e., microcrystalline cellulose, bacterial fibrillated fibers. All showed non-Newtonian even at very low concentrations. property each plateau shear stress, yield over critical concentration. obtained experiment agreed well with value theoretically...
Effects of solvent exchange and milling on the solid structure cellulose were investigated, using small- wide-angle X-ray scattering solid-state NMR. The facilitated dissolution in LiCl/DMAc with no change crystalline cellulose. In contrast, never cellulose, though was almost destroyed. These facts show that hardly affects LiCl/DMAc. fractal dimensions determined by small-angle measurements increased exchange, suggesting aggregation state microfibril is affected. It also suggested NMR 1H...
Solution properties and molecular structure of tunicate cellulose (TC), an animal from Halocynthia roretzi, were investigated in terms rheological dilute solution properties. The solvent used is 8 wt % LiCl/1,3-dimethyl-2-imidazolidinone (DMI). A dissolving pulp (DP), derived plant, was also for comparison. weight-average weight, Mw, the limiting viscosity number, [eta], TC evaluated to be 413 x 10(6) 2645 mL/g, respectively. showed same concentration dependence GN (GN=5.49 10(6)phiw(2.1)4...
Abstract Summary: Cellulose gels were prepared from cellulose in lithium chloride/ N , ‐dimethylacetamide (LiCl/DMAc) solution. When the concentration solution is above one at which molecules overlap, formed. While gel by addition of water was turbid, ion exchange colorless, transparent, and optically anisotropic. In order to explain this gelation behavior cellulose, small‐angle X‐ray scattering (SAXS) measurements solutions performed. The SAXS profiles suggested that large‐scale fluctuation...
Abstract The photocatalytic activity of graphitic carbon nitride ( g ‐C 3 N 4 ) was dramatically enhanced by ultra‐low loading Ru6 clusters (0.01 wt %). This accomplished via the equilibrium adsorption a Ru(NO)(NO precursor followed annealing at 550 °C under an inert atmosphere. Varying both type Ru and temperature permitted tuning local structure centers between single site nanoparticle morphologies. These variations in played crucial role determining H 2 evolution material aqueous media...
Cellulose nanofibrils (CNFs) have been employed as sustainable, eco-friendly fillers in high-performance nanocomposites, although such materials may exhibit poor impact tolerance. The present work synthesized high impact-resistance plastics based on plant cell-wall-like frameworks produced by coating 500 μm isotactic polypropylene (iPP) microspheres with ultratrace amounts of amphiphilic bamboo CNFs prepared the aqueous counter collision method. These were spontaneously coated when combined...
Differences in molecular properties of celluloses from different biological origins were investigated chiefly terms the rheological their solutions 8 wt % LiCl/N, N-dimethylacetamide (DMAc). Cotton linter (CC) and dissolving pulp (DP) used as cellulose samples derived plant, a Acetobacter xylinum was also bacterial (BC). For three kinds solutions, values η0 − ηs (η0: zero shear rate viscosity solution, ηs: solvent viscosity) proportion to weight fraction polymer, φw, dilute region. On other...
Abstract Cellulose nanofibrils (CNFs) obtained by aqueous counter collision (ACC) methods have amphiphilic Janus-type properties, which appear markedly for ACC–CNFs prepared from bacterial nanocellulose (BNC) pellicles. The surface is exposed because of the mechanism involved in ACC pulverizing cellulose materials, predominant interactions (2 0 0) lattice plane I crystal structure are weak interplanar van der Waals interactions. Such selective cleavage more likely to occur highly crystalline...
Abstract In the present study, crystalline cellulose biomass material was converted into carbon nanoparticles via carbonization to activated with micropores of various sizes. This subsequently subjected aqueous counter collision (ACC) produce hydrophobic porous functional particles. Initially, raw carbonized materials pore distributions prior ACC. Pore distribution depended on activation time, and confirmed by nitrogen (N 2 ) adsorption isotherms. The surface areas volumes for 8 h were...
Tsunami waveforms can be observed at offshore locations such as sea-bottom pressure gauges or GPS-mounted buoys. Recent work has focused on using these observations to make near-field tsunami forecasts in real time. However, existing forecasting methods are limited that they do not provide uncertainty estimates. This study develops a method with The embeds conditional autoregressive model hierarchical Bayesian inverse model. Since we sample from the posterior distribution of interest Markov...
Rheological properties of cellulose fibrous suspensions were measured with a cone-plate type rheometer. Effect particle concentrations, c, and salt concentrations the systems on studied. The flow curve fully dialyzed system showed Newtonian at concentration 0.1 wt%. However, it plateau regions shear stress over ca. 0.3 wt%, which is consistent critical c0 calculated from aspect ratio fiber particle. dynamic moduli almost independent angular frequency. They in proportion to c9/4. absolute...
The structure of a semidilute solution mercerized cellulose (CC1m) in 8% (w/w) LiCl·DMAc, which contained some aggregates, was investigated using static and dynamic light scattering measurements. function the polymer containing small amount aggregates can be separated into fast- slow-mode components by combining osmotic modulus identical for fast-mode component CC1m solutions native (CC1) solutions, is dispersed molecularly. This indicates that molecularly has an conformation with molecules...
Abstract Effect of solvent exchange, i.e., the sequential immersion in water, acetone, and DMAc on pore structure cellulose its dissolution behavior lithium chloride/ N , ‐dimethylacetamide (LiCl/DMAc) was investigated by using size exclusion liquid chromatography (SEC), dynamic light scattering (DLS), small‐angle X‐ray (SAXS). In SEC experiment, poly(styrene)s, diethyl phthalate, acetone were used as probe solutes 2‐butanone an eluent. Capacity factor these solvent‐exchanged larger than...
Ulva sp. is a type of green algae and widely distributed in coastal areas around the world due to eutrophication. Effective utilization expected for establishment carbon-neutral biochemical production. Microwave-assisted hydrothermal extraction one most efficient ways extracting highly functional polysaccharides called ulvan. Here, we demonstrate importance microwave frequency enhancing ulvan from meridionalis. We found that microwaves (2.45 GHz) selectively heat water solvent, while radio...
Abstract A series of nanoporous carbon nitrides that contained a range alkali metal cations (M@nanoC 3 N 4 : M=Li + , Na K Rb and Cs ) have been successfully synthesized from as‐synthesized g‐C by delamination with concentrated sulfuric acid, followed neutralization aqueous solutions the corresponding hydroxides. Tris(2,2′‐bipyridine)ruthenium(II) complexes, [Ru(bpy) ] 2+ were grafted onto in an effort to explore physicochemical properties deposited as well its photocatalytic activity...
Effect of aluminum sulfate, Al2(SO4)3, on dispersion state sodium carboxymethylcellulose, NaCMC, in aqueous solution was investigated by rheological measurements and X-ray photoelectron spectroscopy (XPS). Rheological properties NaCMC solutions containing Al2(SO4)3 were using a cone-plate type rheometer. When concentration 0.5 wt %, shear stress the slightly decreased with increasing Al2(SO4)3. On other hand, when 5 increased concentration. In this case, both dynamic storage loss moduli also...
The rheological properties of pulp and PET fiber suspensions were measured with a parallel-plates type rheometer. A high speed CCD camera was used to observe the changes in floc structures that produced during measurement. flow curves showed Newtonian low shear rate range. With increasing rate, stress increased then became unstable, namely, jumps observed, which are due formation flocs. At higher flocs disappeared systems again. polyethylene terephthalate (PET) non-Newtonian even We found...
Abstract Semidilute solution of cotton lint (CC1) in 8 wt % LiCl/ N,N ‐dimethylacetamide was investigated using static light scattering (SLS) and rheological measurements. The reduced osmotic modulus estimated by SLS measurements for CC1 solutions are proportional to c 1. 16 the semidilute region. From exponent 1.16, de Gennes' scaling theory derives relationship between radius gyration, R g , molecular weight, M w as ∝ 0 . 62 This corresponds Mark‐Houwink‐Sakurada 0.86. is very close that...
The effect of mercerization on the cellulose solution was investigated in terms rheological and dilute properties 8 wt % LiCl/N,N-dimethylacetamide (DMAc). Cotton lint, cotton linter, dissolving pulp were used for native samples. Static light scattering (SLS) measurements show that second virial coefficient, A2, solutions decreased by mercerization, indicating affinity between solvent molecules mercerization. A long time relaxation found only mercerized viscoelastic semidilute solutions....