A5073136789- Gamma-ray bursts and supernovae
- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Astronomy and Astrophysical Research
- Stellar, planetary, and galactic studies
- Astro and Planetary Science
- Magnetism in coordination complexes
- Pulsars and Gravitational Waves Research
- Crystallography and molecular interactions
- Metal complexes synthesis and properties
- Porphyrin and Phthalocyanine Chemistry
- Astrophysical Phenomena and Observations
- Enzyme Structure and Function
- Advancements in Battery Materials
- Advanced Battery Materials and Technologies
- SAS software applications and methods
- Heat Transfer and Optimization
- Thermal Expansion and Ionic Conductivity
- Nuclear Physics and Applications
- Neutrino Physics Research
- Machine Learning in Materials Science
- Supramolecular Chemistry and Complexes
- Crystal structures of chemical compounds
- Thermal and Kinetic Analysis
- Organic and Molecular Conductors Research
Battery Park
2025
Institute of Science Tokyo
2025
Tokyo Institute of Technology
2023-2024
Tokyo University of Science
2009-2020
University of Tokyo Health Sciences
2020
Kobe University
2020
Shinjuku College of Information Technology
2019
The University of Tokyo
1987-2013
Kavli Institute for the Physics and Mathematics of the Universe
2009
Brookhaven National Laboratory
1987
No design rules have yet been established for producing solid electrolytes with a lithium-ion conductivity high enough to replace liquid and expand the performance battery configuration limits of current lithium ion batteries. Taking advantage properties high-entropy materials, we designed highly ion-conductive electrolyte by increasing compositional complexity known superionic conductor eliminate migration barriers while maintaining structural framework conduction. The synthesized phase...
We present early phase observations in optical and near-infrared wavelengths for the extremely luminous Type Ia supernova (SN Ia) 2009dc. The decline rate of light curve is $\Delta m_{15}(B)=0.65\pm 0.03$, which one slowest among SNe Ia. peak $V$-band absolute magnitude $M_{V}=-19.90\pm 0.15$ mag even if host extinction $A_{V}=0$ mag. It reaches $M_{V}=-20.19\pm 0.19$ $A_{V}=0.29$ as inferred from observed Na {\sc i} D line absorption host. Our $JHK_{s}$-band photometry shows that SN most...
We developed a new convertible copper(I) complex using 2-pyridyl-4-methylpyrimidine and diphosphine as ligands. This exhibited mechanical bistability based on the inversion motion of pyrimidine ring, leading to dual luminescence behavior. The dynamics was strongly dependent temperature solvent. Variable-temperature (1)H NMR spectra revealed that two isomers interconverted in solution via ring inversion, frozen below 200 K. characteristic CT absorption emission bands solution. Emission...
We here describe the first metal complex system in which electronic signals can be repeatedly extracted by converting bistable states related to an intramolecular ligand rotational motion, is fueled visible light. The molecular structure for relating electron transfer and a motion consists of copper center coordinated unsymmetrically substituted pyrimidine derivative, whose isomerization causes electrochemical potential shift. To harness light energy effectively through metal-to-ligand...
We have constructed a single molecule system, consisting of ferrocene-tethered copper complex, in which electron transfer between redox centers is triggered by molecular rotational motion. In the compound, an asymmetric methyl-substituted 2,2'-pyridylpyrimidine ligand, tethered to ferrocene moiety, has two isomeric ring-inversion coordination conformations around center. Both structures were characterized X-ray crystallography. (1)H NMR and electrochemical measurements revealed that these...
We have succeeded in constructing an electron-transfer gating system involving a copper complex, 1.BF(4), that is regulated by the rotational motion of pyridylpyrimidine ligand. 4-Methyl-2-(2'-pyridyl)pyrimidine confined between two bulky groups underwent dynamic process derived from pyrimidine-ring coordination inversion inner and outer isomers, these isomers interconverted with each other solution barrier 73 kJ mol(-1) at 293 K. As ring-inversion induces change redox potential on center,...
We describe herein the effect of solvated ion pairing on molecular motion a pyrimidine ring coordinated copper center. synthesized series heteroleptic copper(I) complex salts bearing an unsymmetrically substituted pyridylpyrimidine and bulky diphosphine. Two rotational isomers complexes were found to coexist interconvert in solution via intramolecular ligating atom exchange ring, where notation inner (i-) outer (o-) describes orientation relative The stability was solvent-...
JWST was conceived and built to answer one of the most fundamental questions that humans can address empirically: "How did Universe make its first stars?". Our First Lights At REionization (FLARE) project transforms quest for epoch reionization from static time domain. It targets complementary question: "What happened those will be answered by observations luminous events: supernovae accretion on black holes formed direct collapse primordial gas clouds. These transients provide constraints...
view Abstract Citations (26) References (14) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Collapsing White Dwarfs Baron, E. ; Cooperstein, J. Kahana, S. Nomoto, K. The authors present the results of hydrodynamic collapse an accreting C+O white dwarf. Collapse is induced by electron captures in iron core behind a conductive deflagration front. shock wave produced bounce stalls at about 115 km, and thus neutron star formed such model would be as optically...
The 1 : mixture of adenine and thymine both substituted with dodecyl groups exhibited the unique thermal behavior.
In the next decade Type Ia supernovae (SNe Ia) will be used to test theories predicting changes in Dark Energy equation of state with time. Ultimately this requires a dedicated space mission like JDEM. SNe are mature cosmological probes --- their limitations well characterized, and path improvement is clear. Dominant systematic errors include photometric calibration, selection effects, reddening, population-dependent differences. Building on past lessons, well-controlled new surveys poised...
A series of [Ni(dmit)2]− (dmit: 1,3-dithiole-2-thione-4,5-dithiolato) salts alkyltrimethylammonium (Cn: n represents the alkyl chain length; = 3 and 5–18) have been prepared analyzed by X-...
Abstract Molecules exhibiting cold crystallization, an exothermic phenomenon in heating following supercooling, can be used as a heat storing material. On the other hand, examples non-polymers are still few. A chiral Schiff-base nickel(II) complex, which had characteristic methyl group and long alkyl chains, exhibited complicated thermal behavior including crystallization. The was steric barrier to dimerization molecular stacking, leading supercooled state. In addition, of enantiomer...
Gamma-ray bursts (GRBs) and their afterglows have been proposed as an excellent probe to study the evolution of cosmic star formation, reionization intergalactic medium, metal enrichment history universe, since prompt gamma-ray emission GRBs should be detectable out distances z>10. Hitherto, highest measured redshift for a GRB has z=4.50. Here we report optical spectrum afterglow 050904 obtained 3.4 days after burst. The shows clear continuum at long wavelength end with sharp cutoff...
The redox properties of copper pyridylpyrimidine complexes, which undergo linkage isomerism based on pyrimidine ring rotation, were compared under different coordination environments. A newly synthesized compound, [Cu(Mepypm)(L(Mes))]BF4 (1·BF4, Mepypm = 4-methyl-2-(2'-pyridyl)pyrimidine, L(Mes) 2,9-dimesityl-1,10-phenanthroline) was with previously reported complexes [Cu(MepmMepy)(L(Mes))]BF4 (2·BF4, MepmMepy 4-methyl-2-(6'-methyl-2'-pyridyl)pyrimidine), Cu(Mepypm)(DPEphos)]BF4 (3·BF4,...
view Abstract Citations (18) References (17) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The Ring around SN 1987A and Rotation of the Progenitor Eriguchi, Y. ; Yamaoka, H. Nomoto, K. Hashimoto, M. ring discovered is likely to be related rotation progenitor. We have studied two rotational effects progenitor 1987A: (1) mass-shedding from equator (2) an aspherical mass distribution in a stellar wind due direction- dependent loss. With approximate models for...
Abstract Crystal structures of eight derivatives bis(diphenylglyoximato)–nickel(II), bearing four alkoxy chains different lengths, were determined by single-crystal X-ray crystallography. Sequential transition packing chain elongation was observed. The typically one-dimensional columnar structure comprising metal wires, herringbone structures, quasi-layered and layered having an interdigitation alkyl moieties in the chains. Each structural characteristic depends on odd–even effect...
To develop inorganic Li conductors for all-solid-state Li-ion batteries, the present study clarified temperature-dependent structural changes in Li2MS3 (M = Si, Si0.5Ge0.5, Ge) phases, where new crystal structures favoring ionic conduction are potentially formed. Structural analysis was performed on powder X-ray diffraction data obtained at high temperatures. At 600 °C, tetragonal phases were formed all three cases. Meanwhile, cooling from °C different according to M species, leading various...
Precise evaluation of the thermophysical properties thin films is crucial for realizing high-performance flexible electrical and energy devices. The ultrafast laser-based time-domain thermoreflectance (TDTR) method one most effective methods examining attached to metals; however, conventional TDTR are mainly employed an aluminum transducer layer, which not used metal electrodes. Here, we developed a system designed gold transducer, typical electrode in electronic devices, evaluated carbon...