75 research outputs found
Growth of self-integrated atomic quantum wires and junctions of a Mott semiconductor
1ナノメートル半導体量子細線の作製に成功 --量子の熱帯魚パターンが拓く未来のナノテク--. 京都大学プレスリリース. 2023-05-08.Continued advances in quantum technologies rely on producing nanometer-scale wires. Although several state-of-the-art nanolithographic technologies and bottom-up synthesis processes have been used to engineer these wires, critical challenges remain in growing uniform atomic-scale crystalline wires and constructing their network structures. Here, we discover a simple method to fabricate atomic-scale wires with various arrangements, including stripes, X-junctions, Y-junctions, and nanorings. Single-crystalline atomic-scale wires of a Mott insulator, whose bandgap is comparable to those of wide-gap semiconductors, are spontaneously grown on graphite substrates by pulsed-laser deposition. These wires are one unit cell thick and have an exact width of two and four unit cells (1.4 and 2.8 nm) and lengths up to a few micrometers. We show that the nonequilibrium reaction-diffusion processes may play an essential role in atomic pattern formation. Our findings offer a previously unknown perspective on the nonequilibrium self-organization phenomena on an atomic scale, paving a unique way for the quantum architecture of nano-network
イガン サイハツゴ ノ テイアルブミン ケッショウ ト ナンジセイ オウト ニ ハロペリドール ガ ユウコウ デアッタ イチショウレイ
The patient was an 83-year-old woman who underwent laparoscopy-assisted distal gastrectomy for gastric cancer on February 25, 201X. S‐1 and UFT were performed, but metastatic liver cancer was seen on a CT scan on September 2. S‐1 was restarted on October 26 but discontinued on January 18, 201X+1 and best supportive care was adopted. She was hospitalized on April 15 for loss of appetite and anasarca. The patient had intractable vomiting and treatment resistance to metoclopramide and domperidone. ALB had decreased to 1.3 g/dl on April 22. A decrease in gastrointestinal motility from ascites retention was seen on a CT scan on April 25. Continuous subcutaneous infusion with haloperidol was started on April 25. The frequency of vomiting significantly decreased immediately afterward, and daily caloric intake significantly increased. Her ascites and anasarca were markedly improved on a CT scan on May 11. ALB had risen to 2.7 g/dlon June 14. Continuous subcutaneous infusion of haloperidol was effective for hypoalbuminemia and intractable vomiting after gastric cancer recurrence
Charge-changing cross section measurements of 300 MeV/nucleon Si on carbon and data analysis
Charge-changing cross section () measurements via the
transmission method have made important progress recently aiming to determine
the charge radii of exotic nuclei. In this work, we report a new
measurement of 304(9) MeV/nucleon Si on carbon at
the second Radioactive Ion Beam Line in Lanzhou (RIBLL2) and describe the data
analysis procedure in detail. This procedure is essential to evaluate the
systematic uncertainty in the transmission method. The determined
of 1125(11) mb is found to be consistent with the
existing data at similar energies. The present work will serve as a reference
in the determinations at RIBLL2.Comment: 9 pages, 13 figures, to be published in Chinese Physics
The ASTRO-H X-ray Observatory
The joint JAXA/NASA ASTRO-H mission is the sixth in a series of highly
successful X-ray missions initiated by the Institute of Space and Astronautical
Science (ISAS). ASTRO-H will investigate the physics of the high-energy
universe via a suite of four instruments, covering a very wide energy range,
from 0.3 keV to 600 keV. These instruments include a high-resolution,
high-throughput spectrometer sensitive over 0.3-2 keV with high spectral
resolution of Delta E < 7 eV, enabled by a micro-calorimeter array located in
the focal plane of thin-foil X-ray optics; hard X-ray imaging spectrometers
covering 5-80 keV, located in the focal plane of multilayer-coated, focusing
hard X-ray mirrors; a wide-field imaging spectrometer sensitive over 0.4-12
keV, with an X-ray CCD camera in the focal plane of a soft X-ray telescope; and
a non-focusing Compton-camera type soft gamma-ray detector, sensitive in the
40-600 keV band. The simultaneous broad bandpass, coupled with high spectral
resolution, will enable the pursuit of a wide variety of important science
themes.Comment: 22 pages, 17 figures, Proceedings of the SPIE Astronomical
Instrumentation "Space Telescopes and Instrumentation 2012: Ultraviolet to
Gamma Ray
The Quiescent Intracluster Medium in the Core of the Perseus Cluster
Clusters of galaxies are the most massive gravitationally-bound objects in
the Universe and are still forming. They are thus important probes of
cosmological parameters and a host of astrophysical processes. Knowledge of the
dynamics of the pervasive hot gas, which dominates in mass over stars in a
cluster, is a crucial missing ingredient. It can enable new insights into
mechanical energy injection by the central supermassive black hole and the use
of hydrostatic equilibrium for the determination of cluster masses. X-rays from
the core of the Perseus cluster are emitted by the 50 million K diffuse hot
plasma filling its gravitational potential well. The Active Galactic Nucleus of
the central galaxy NGC1275 is pumping jetted energy into the surrounding
intracluster medium, creating buoyant bubbles filled with relativistic plasma.
These likely induce motions in the intracluster medium and heat the inner gas
preventing runaway radiative cooling; a process known as Active Galactic
Nucleus Feedback. Here we report on Hitomi X-ray observations of the Perseus
cluster core, which reveal a remarkably quiescent atmosphere where the gas has
a line-of-sight velocity dispersion of 164+/-10 km/s in a region 30-60 kpc from
the central nucleus. A gradient in the line-of-sight velocity of 150+/-70 km/s
is found across the 60 kpc image of the cluster core. Turbulent pressure
support in the gas is 4% or less of the thermodynamic pressure, with large
scale shear at most doubling that estimate. We infer that total cluster masses
determined from hydrostatic equilibrium in the central regions need little
correction for turbulent pressure.Comment: 31 pages, 11 Figs, published in Nature July
Coulomb dissociation of N 20,21
Neutron-rich light nuclei and their reactions play an important role in the creation of chemical elements. Here, data from a Coulomb dissociation experiment on N20,21 are reported. Relativistic N20,21 ions impinged on a lead target and the Coulomb dissociation cross section was determined in a kinematically complete experiment. Using the detailed balance theorem, the N19(n,γ)N20 and N20(n,γ)N21 excitation functions and thermonuclear reaction rates have been determined. The N19(n,γ)N20 rate is up to a factor of 5 higher at
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