491 research outputs found
Instrumental Resolution of the Chopper Spectrometer 4SEASONS Evaluated by Monte Carlo Simulation
We performed simulations of the resolution function of the 4SEASONS
spectrometer at J-PARC by using the Monte Carlo simulation package McStas. The
simulations showed reasonably good agreement with analytical calculations of
energy and momentum resolutions by using a simplified description. We
implemented new functionalities in Utsusemi, the standard data analysis tool
used in 4SEASONS, to enable visualization of the simulated resolution function
and predict its shape for specific experimental configurations.Comment: 8 pages, 5 figure
Time-domain Brillouin scattering assisted by diffraction gratings
Absorption of ultrashort laser pulses in a metallic grating deposited on a
transparent sample launches coherent compression/dilatation acoustic pulses in
directions of different orders of acoustic diffraction. Their propagation is
detected by the delayed laser pulses, which are also diffracted by the metallic
grating, through the measurement of the transient intensity change of the first
order diffracted light. The obtained data contain multiple frequency components
which are interpreted by considering all possible angles for the Brillouin
scattering of light achieved through the multiplexing of the propagation
directions of light and coherent sound by the metallic grating. The emitted
acoustic field can be equivalently presented as a superposition of the plane
inhomogeneous acoustic waves, which constitute an acoustic diffraction grating
for the probe light. Thus, the obtained results can also be interpreted as a
consequence of probe light diffraction by both metallic and acoustic gratings.
The realized scheme of time-domain Brillouin scattering with metallic grating
operating in reflection mode provides access to acoustic frequencies from the
minimal to the maximal possible in a single experimental configuration for the
directions of probe light incidence and scattered light detection. This is
achieved by monitoring of the backward and forward Brillouin scattering
processes in parallel. Applications include measurements of the acoustic
dispersion, simultaneous determination of sound velocity and optical refractive
index, and evaluation of the samples with a single direction of possible
optical access.Comment: 21 pages, 4 figures, 1 tabl
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An examination of the processes by which construal level affects the implicit evaluation of goal relevant stimuli.
Previous research has found that construal level—how abstractly or concretely people represent events—can impact implicit evaluations. Abstract high-level construal (vs. concrete low-level construal) promotes evaluative responses consistent with global (strongly held, long-term) rather than local (short-term, situational) goals. It remains unclear by what cognitive process(es) this occurs. In this paper, we examine two
possibilities. High-level construal might enhance the unintended influence of activated evaluative associations or facilitate the detection and implementation of intentional responses. To examine these possibilities, the current study applies a multinomial processing tree model to data from Fujita and Han (2009). Results suggest that high-level construal facilitates goal-consistent evaluations by increasing both the unintentional influence of activated goal-consistent positive associations and the intentional detection of and implementation of accurate responding to goal-relevant stimuli. These findings extend our understanding of how construal level promotes goal consistent
evaluations
Horizontal distribution and annual fluctuations in abundance of settled juveniles of the black sea bream Acanthopagrus schlegelii in Hiroshima Bay, Japan
広島湾においてクロダイ稚魚の着底・成育に適した環境条件を把握する目的で,同湾沿岸の稚魚の生息密度を明らかにした。稚魚は2006–2009年6–7月に広島湾内18定点で採集した(n=2,488)。さらに,調査定点のうち最も高い稚魚密度(35.83 inds./100m2)を観測した能美島鹿田において,2013–2016年の7–9月にかけて稚魚を採集し(n=1,588),密度の年変動を観察した。その結果,広島湾の全平均密度は3.78 inds./100m2となり,密度の高い4定点はいずれも厳島,能美島西岸であった。密度が高い定点の特徴として,潮流が物理的に遮られた静穏域の砂浜帯で,淡水流入があることが挙げられた。密度には年変動があり,近年は減少傾向にあることが判明した。広島湾クロダイの資源加入量が低下している可能性が示唆された。To obtain basic information on the optimal nursery grounds for black sea bream Acanthopagrus schlegelii recruits, juvenile density in Hiroshima Bay was calculated. Juveniles (n=2,488) were collected from 18 sampling stations around Hiroshima Bay using surf zone nets during the early summer from 2006 to 2009. to assess the annual fluctuations of juvenile density, samples were continuously caught from one station (St. 1) on the western side of Noumishima Island from 2013 to 2016. Relatively high densities were recorded from four stations (St. 1, 2, 6 and 10) located along the Ohno Seto Strait and the western side of Noumishima Island. These sampling stations shared three common characteristics that likely explain the observed higher juvenile density, namely (1) moderate currents with calm areas protected by physical barrier, (2) sandy muddy beaches (tidal flats) and (3) freshwater inflows or run-off. Juvenile density showed an annual decreasing trend, suggesting that fish stock levels of black sea bream are declining in Hiroshima Bay
Thermal stability of α-Ga2O3 films grown on c-plane sapphire substrates via mist-CVD
The thermal stability of α-Ga2O3 films grown on c-plane sapphire substrates was investigated. A strong correlation was found between thermal stability and film thickness: the more the α-Ga2O3 films maintained the α-phase upon heating at higher annealing temperature, the thinner they were. Transmission electron microscopy observations revealed that the phase transition of the α-Ga2O3 film to the thermodynamically most stable β-phase had the orientation relationship of β-Ga2O3 [2̄ 01] || sapphire [0001]. High-temperature x-ray diffraction measurement for the α-Ga2O3 film showed the relationship of β-Ga2O3 [4̄ 01]/[301] || sapphire [0001] as well. The dependence of the stability boundary on the film thickness originates from a thermal stress caused by a larger thermal expansion coefficient of α-Ga2O3 than that of sapphire. Relaxation of residual stress by introducing a selective area growth technique enhanced the thermal stability of α-Ga2O3 so that α-Ga2O3 maintained the corundum structure upon heating at 800 °C, although a small diffraction peak from β-Ga2O3 was detected by x-ray diffraction measurement. The enhanced thermal stability of α-Ga2O3 widens device process windows as well as growth windows
Natural band alignment of alloys
We have calculated formation enthalpies, band gaps, and natural band
alignment for alloys by first principles calculation based
on density functional theory. The calculated formation enthalpies show that the
alloys exhibit a large miscibilitygap, and a metastable
region was found to occur when the S content was below 18% or over 87%. Effect
of S incorporation for band gaps of alloys shows large
bowing parameter (b 13 eV) induced. The dependence of the band
lineup of alloys on the S content by using two different
methods, and the change in the energy position of valence band maximum (VBM)
was larger than that of conduction band minimum. Based on the calculated VBM
positions, we predicted that with S content 10 to 18% can
be surface charge transfer doping by high electron affinity materials. The
present work provides an example to design for p-type oxysulfide materials.Comment: 22 pages, 6 figure
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New directions in self-regulation: the role of metamotivational beliefs
Research on self-regulation has primarily focused on how people exert control over their thoughts, emotions, and behavior. Less attention has been paid to the ways in which people manage their motivational states in the service of achieving valued goals. In the present paper, we explore an emerging line of research that focuses on people’s beliefs about their own motivation (i.e., their metamotivational knowledge), as well as the influence of these beliefs on their selection of regulatory strategies. In particular, we review evidence showing that people are often quite sensitive to the fact that distinct motivational states (e.g., eagerness vs. vigilance) are adaptive for different kinds of tasks. We also discuss how other metamotivational beliefs are inaccurate on average (e.g., beliefs about how rewards affect intrinsic motivation). Finally, we consider the implications of metamotivation research for the field of self-regulation and discuss future directions
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