A5084444640- Carbon Nanotubes in Composites
- Graphene research and applications
- 2D Materials and Applications
- Thermal properties of materials
- Magnetic confinement fusion research
- Particle accelerators and beam dynamics
- Fullerene Chemistry and Applications
- Boron and Carbon Nanomaterials Research
- Superconducting Materials and Applications
- Diamond and Carbon-based Materials Research
- MXene and MAX Phase Materials
- Mechanical and Optical Resonators
- Force Microscopy Techniques and Applications
- Advancements in Battery Materials
- Nanowire Synthesis and Applications
- Thermal Radiation and Cooling Technologies
- Nanopore and Nanochannel Transport Studies
- Photonic and Optical Devices
- Topological Materials and Phenomena
- Molecular Junctions and Nanostructures
- Catalytic Processes in Materials Science
- Photonic Crystals and Applications
- Perovskite Materials and Applications
- Vibration Control and Rheological Fluids
- Vibration and Dynamic Analysis
Osaka University
2021-2025
Mejiro University
2022-2025
The University of Tokyo
2015-2024
Waseda University
2023-2024
Meiji University
2024
University of Tsukuba
2022
National Institute for Fusion Science
2002-2021
National Institute of Advanced Industrial Science and Technology
2021
Central Research Institute of Electric Power Industry
1988-2019
Honda (Japan)
2001-2016
A procedure for estimating the inertia constant M(=2H) of a power system and total on-line capacity spinning-reserve support generators, using transients frequency measured at an event such as generator load rejection test, is presented. polynomial approximation with respect to time applied waveform in constant, simple model based on idea average assumed generators. Results estimation 10 events show that 60 Hz Japan around 14 18 seconds base, generators 20 40% load. The proposed expected be...
Growing coaxial nanotubes Heterostructures of highly crystalline two-dimensional materials such as graphene, hexagonal boron nitride (hBN), and molybdenum disulfide (MoS 2 ) are now routinely assembled from films or grown layers. Xiang et al. report the growth one-dimensional analogs these heterostructures on single-walled carbon (SWCNTs) through a chemical vapor deposition (see Perspective by Gogotsi Yakobson). Single-crystalline monolayers multilayers hBN MoS were that maintained...
Recently, W-based catalysts have provided a promising route to synthesize single-walled carbon nanotubes (SWCNTs) with specific chirality, but the mechanism of growth selectivity is vaguely understood. We propose strategy identify atomic structure as well evolution Co-W-C ternary SWCNT catalyst. The key use thin SiO2 film catalyst support and observation window. As uniformly prepared on this directly used for synthesis, method has an advantage over conventional methods: it creates...
We synthesized randomly percolated and vertically aligned single-walled carbon nanotubes (SWNTs) with tunable subnanometer diameters (0.7–0.9 nm) on quartz substrates by Cu-anchored Co catalysts.
Synthesis of single-walled carbon nanotubes (SWNTs) with well-defined atomic arrangements has been widely recognized in the past few decades as biggest challenge SWNT community, and become a bottleneck for application SWNTs nano-electronics. Here, we report selective synthesis (12, 6) an enrichment 50%-70% by chemical vapor deposition (CVD) using sputtered Co-W catalyst. This is achieved under much milder reduction growth conditions than those previous transition-metal molecule clusters...
Single-walled and multiwalled molybdenum disulfide (MoS2) nanotubes have been coaxially synthesized on small-diameter boron nitride (BNNTs) that are obtained from removing single-walled carbon (SWCNTs) in heteronanotubes of SWCNTs coated by BNNTs. The photoluminescence (PL) MoS2 supported core BNNTs is observed this work, which evidences the direct bandgap structure with a diameter around 6−7 nm. observation consistent our DFT results nanotube changes an indirect-gap to direct-gap...
Significance We recently synthesized coaxially nested one-dimensional van der Waals heterostructures in which boron nitride nanotubes or molybdenum disulfide grew seamlessly on a single-walled carbon nanotube template. In this work, edge structures, nucleation sites, and crystal epitaxial relationships heteronanotubes are unambiguously revealed by nondestructive transmission electron microscopic technique. These understandings, together with the characterization technique developed here, can...
An active control system for low-frequency road noise in automobiles combined with an audio is developed as a commercial application the first time world, and installed station wagon. The purpose of this paper to provide outline describe newly cost-reduction technology used it, since reduction costs major reason that could successfully be applied product. methods reduce include utilization feedback control, implementation by analogue circuits, common use speakers. This reduces front seat...
This paper proposes applying the two-stage diagonally implicit Runge-Kutta (2S-DIRK) method of numerical integration to calculation electromagnetic transients (EMTs) in a power system. The accuracy and stability 2S-DIRK are almost same as those trapezoidal method, while does not produce sustained oscillation due sudden change an inductor current or capacitor voltage unlike method. First, this reviews scheme derives formulas inductors capacitors for both linear nonlinear cases. Then,...
We investigated the thermal and electrical conductivity of water seeded with single-walled carbon nanotubes (SWCNT) synthesized using alcohol catalytic chemical vapour deposition method. Sodium deoxycholate was used as surfactant to prepare stable nanofluids, which we then thoroughly characterized by microscopic spectroscopic methods. Electrical measurements showed power law dependence respect SWCNT loading, while increase a linear on loading. The effective nanofluid also found increasing...
Carbon nanotubes (CNTs) and boron nitride (BNNTs) are one-dimensional materials with high thermal conductivity similar crystal structures. Additionally, BNNTs feature higher stability in air than CNTs. In this work, a single-walled carbon nanotube (SWCNT) film was used as template to synthesize BNNT coating by the chemical vapor deposition (CVD) method form coaxial heterostructure. Then, contact-free steady-state infrared (IR) adopted measure in-plane sheet conductance of as-synthesized...
The synthesis of one-dimensional van der Waals heterostructures was realized recently, which offers alternative possibilities for prospective applications in electronics and optoelectronics. even reduced dimension will enable different properties further miniaturization beyond the capabilities their two-dimensional counterparts. natural doping results p-type electrical characteristics semiconducting single-walled carbon nanotubes n-type molybdenum disulfide with conventional noble metal...
Compared with isolated single-walled carbon nanotubes (SWNTs), thermal conductivity is greatly impeded in SWNT bundles; however, the measurement of bundle size effect difficult. In this study, number SWNTs a was determined based on transferred horizontally aligned suspended micro-thermometer to quantitatively study conductivity. Increasing significantly degraded For SWNTs, approximately 5000 ± 1000 W m–1 K–1 at room temperature, three times larger than that four-SWNT bundle. The...
An organic film-assisted electrical breakdown technique is proposed to selectively remove metallic (m-) single-walled carbon nanotubes (SWNTs) in full length towards creation of pure semiconducting SWNT arrays which are available for the large-scale fabrication field effect transistors (FETs). The horizontally aligned embedded films resulted a maximum removal 16.4 μm. SWNTs was confirmed using scanning electron microscopy and Raman mapping measurements. on/off ratios FETs were improved up...
In March 1998, the LHD project finally completed its eight year construction schedule. is a superconducting (SC) heliotron type device with R = 3.9 m, ap 0.6 m and B 3 T, which has simple continuous large helical coils. The major mission of to demonstrate high potential currentless helical-toroidal plasmas, are free from current disruption have an intrinsic for steady state operation. After intensive physics design studies in 1980s, necessary programmes SC engineering R&D was carried out, as...
A heavy ion beam probe (HIBP) has been installed on the Large Helical Device (LHD). MeV-range is required for LHD-HIBP. The probing accelerated up to 6 MeV by use of a tandem accelerator. new energy analyzer with electrodes also developed analyze such high beam. As result, secondary can be detected and its successfully analyzed. It verified, in principle, that potential profile measured using HIBP.
We present a systematic study on SiO<sub>2</sub> coated sliver nanoparticles, and demonstrate it as thermally robust SERS substrate for monitoring high temperature reactions up to 800 °C.
Identifying the two-dimensional (2D) topological insulating (TI) state in new materials and its control are crucial aspects towards development of voltage-controlled spintronic devices with low-power dissipation. Members 2D transition metal dichalcogenides have been recently predicted experimentally reported as a class TI materials, but most cases edge conduction seems fragile limited to monolayer phase fabricated on specified substrates. Here, we realize controlled patterning 1T^{'}...
Defects in single-walled carbon nanotubes (SWCNTs) degrade their mechanical, electrical, and thermal properties, limiting potential applications. To realize the diverse applications of SWCNTs, it is essential to enhance crystallinity through effective defect healing. However, traditional treatments typically require temperatures above 1800°C, which can alter nanotube structure. Previously, healing SWCNTs was achieved at a relatively low temperature 1100°C, using C2H2 assistance, but...
We investigate the influence of gas pressure on growth horizontally aligned single-walled carbon nanotubes (SWCNTs) R-cut and r-cut crystal quartz substrates by alcohol catalytic chemical vapor deposition (CVD). The density SWCNTs was found to depend highly pressure. A study SWCNT as a function CVD time revealed that continued increase for 10 min at reduced pressure, whereas saturated rapidly higher even though catalysts were not deactivated. argue variation incubation low-pressure is key...