15 research outputs found
Relation between Mixing Processes and Properties of Lithium-ion Battery Electrode-slurry
The mixing process of electrode-slurry plays an important role in the electrode performance of lithium-ion batteries (LIBs). The dispersion state of conductive materials, such as acetylene black (AB), in the electrode-slurry directly influences the electronic conductivity in the composite electrodes. In this study, the relation between the mixing process of electrode-slurry and the internal resistance of the composite electrode was investigated in combination with the characterization of the electrode-slurries by the rheological analysis and the alternating current (AC) impedance spectroscopy. Some of the electrode-slurries showed higher value and gentler slope of the dynamic storage modulus in the low-angular-frequency region and higher thixotropic index than the others depending on the way of the mixing process and the AB content, agreeing with the low electronic volume resistivities of the corresponding composite electrodes and the electrode-slurries, which indicates the AB network growth. The results suggested that the low-viscosity state when AB and active electrode material are mixed contributes to the dispersive AB network. (C) The Author(s) 2021. Published by ECSJ
Coincidence analysis to search for inspiraling compact binaries using TAMA300 and LISM data
Japanese laser interferometric gravitational wave detectors, TAMA300 and
LISM, performed a coincident observation during 2001. We perform a coincidence
analysis to search for inspiraling compact binaries. The length of data used
for the coincidence analysis is 275 hours when both TAMA300 and LISM detectors
are operated simultaneously. TAMA300 and LISM data are analyzed by matched
filtering, and candidates for gravitational wave events are obtained. If there
is a true gravitational wave signal, it should appear in both data of detectors
with consistent waveforms characterized by masses of stars, amplitude of the
signal, the coalescence time and so on. We introduce a set of coincidence
conditions of the parameters, and search for coincident events. This procedure
reduces the number of fake events considerably, by a factor
compared with the number of fake events in single detector analysis. We find
that the number of events after imposing the coincidence conditions is
consistent with the number of accidental coincidences produced purely by noise.
We thus find no evidence of gravitational wave signals. We obtain an upper
limit of 0.046 /hours (CL ) to the Galactic event rate within 1kpc from
the Earth. The method used in this paper can be applied straightforwardly to
the case of coincidence observations with more than two detectors with
arbitrary arm directions.Comment: 28 pages, 17 figures, Replaced with the version to be published in
Physical Review
Results of the search for inspiraling compact star binaries from TAMA300's observation in 2000-2004
We analyze the data of TAMA300 detector to search for gravitational waves
from inspiraling compact star binaries with masses of the component stars in
the range 1-3Msolar. In this analysis, 2705 hours of data, taken during the
years 2000-2004, are used for the event search. We combine the results of
different observation runs, and obtained a single upper limit on the rate of
the coalescence of compact binaries in our Galaxy of 20 per year at a 90%
confidence level. In this upper limit, the effect of various systematic errors
such like the uncertainty of the background estimation and the calibration of
the detector's sensitivity are included.Comment: 8 pages, 4 Postscript figures, uses revtex4.sty The author list was
correcte
Observation results by the TAMA300 detector on gravitational wave bursts from stellar-core collapses
We present data-analysis schemes and results of observations with the TAMA300
gravitational-wave detector, targeting burst signals from stellar-core collapse
events. In analyses for burst gravitational waves, the detection and
fake-reduction schemes are different from well-investigated ones for a
chirp-wave analysis, because precise waveform templates are not available. We
used an excess-power filter for the extraction of gravitational-wave
candidates, and developed two methods for the reduction of fake events caused
by non-stationary noises of the detector. These analysis schemes were applied
to real data from the TAMA300 interferometric gravitational wave detector. As a
result, fake events were reduced by a factor of about 1000 in the best cases.
The resultant event candidates were interpreted from an astronomical viewpoint.
We set an upper limit of 2.2x10^3 events/sec on the burst gravitational-wave
event rate in our Galaxy with a confidence level of 90%. This work sets a
milestone and prospects on the search for burst gravitational waves, by
establishing an analysis scheme for the observation data from an
interferometric gravitational wave detector
Analysis of the intermediate states of an electrode slurry by electronic conductivity measurements
The electronic resistance of composite electrodes for lithium-ion batteries has a non-negligible effect on the charge–discharge performance at high rates. In order to obtain an electrode with a high-rate performance it is important that conductive materials, such as acetylene black (AB), in the electrode slurry form a good electron conduction network. This study evaluated the electron conduction network of various electrode slurries made using different processes and with different solid contents using electronic conductivity measurements of the electrode slurries. The conductivity of the slurry showed a correlation with the rate performance. Depending on the production method and solid content, the conductivity of the slurry changed. The results suggest that the electron conduction network of the slurry is modified by collisions between the AB and active material particles during kneading and by stirring the slurry with excess solvent during dispersion. Measuring the conductivity of the slurry is expected to help determine the conditions of its manufacture
Analysis of the intermediate states of an electrode slurry by electronic conductivity measurements
The electronic resistance of composite electrodes for lithium-ion batteries has a non-negligible effect on the charge–discharge performance at high rates. In order to obtain an electrode with a high-rate performance it is important that conductive materials, such as acetylene black (AB), in the electrode slurry form a good electron conduction network. This study evaluated the electron conduction network of various electrode slurries made using different processes and with different solid contents using electronic conductivity measurements of the electrode slurries. The conductivity of the slurry showed a correlation with the rate performance. Depending on the production method and solid content, the conductivity of the slurry changed. The results suggest that the electron conduction network of the slurry is modified by collisions between the AB and active material particles during kneading and by stirring the slurry with excess solvent during dispersion. Measuring the conductivity of the slurry is expected to help determine the conditions of its manufacture
Development of a New Benzophenone–Diketopiperazine-Type Potent Antimicrotubule Agent Possessing a 2‑Pyridine Structure
A new benzophenone–diketopiperazine-type
potent antimicrotubule
agent was developed by modifying the structure of the clinical candidate
plinabulin (<b>1</b>). Although the right-hand imidazole ring
with a branched alkyl chain at the 5-position in <b>1</b> was
critical for the potency of the antimicrotubule activity, we successfully
substituted this moiety with a simpler 2-pyridyl structure by converting
the left-hand ring from a phenyl to a benzophenone structure without
decreasing the potency. The resultant compound <b>6b</b> (KPU-300)
exhibited a potent cytotoxicity, with an IC<sub>50</sub> value of
7.0 nM against HT-29 cells, by strongly binding to tubulin (<i>K</i><sub>d</sub> = 1.3 μM) and inducing microtubule depolymerization