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Institution

Waseda University

EducationTokyo, Japan
About: Waseda University is a education organization based out in Tokyo, Japan. It is known for research contribution in the topics: Large Hadron Collider & Catalysis. The organization has 24220 authors who have published 46859 publications receiving 837855 citations. The organization is also known as: Waseda daigaku & Sōdai.


Papers
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Journal ArticleDOI
Eiichi Kikuchi1
TL;DR: In this article, a composite membrane consisting of thin palladium layer deposited on the outer surface of porous ceramics by electroless-plating was proposed to overcome the limitations caused by Pd membranes, such as hydrogen embrittlement.

285 citations

Journal ArticleDOI
TL;DR: In this paper, a new anomalous thermal lattice expansion of LaCoO 3 near 500 K was revealed, which indicates the existence of a second spin state transition, in addition to the one previously established near 100 K. The model parameters indicate that the initially large energy difference between IS and HS states decreases towards zero as the second transition proceeds.
Abstract: Neutron-diffraction measurements have revealed a new anomalous thermal lattice expansion of LaCoO 3 near 500 K that indicates the existence of a second spin-state transition, in addition to the one previously established near 100 K. The anomalous expansion and the temperature dependence of the Co magnetic moments are successfully interpreted in a wide temperature range based on a simple model assuming low-spin (LS, S =0), intermediate-spin (IS, S =1), and high-spin (HS, S =2) states of Co atoms. The first spin transition, near 100 K, is from LS to IS, and the second, near 500 K, is from IS to a mixed state of IS and HS. The fitted model parameters indicate that the initially-large energy difference between IS and HS states decreases towards zero as the second transition proceeds. The large drop in resistivity associated with the latter transition appears to be correlated with the population of the HS state.

285 citations

Journal ArticleDOI
01 Nov 1999
TL;DR: In this article, the limit case of Sobolev's inequalities was studied in RN and the best exponents αN were shown to be false for all α ∈ (0, αN), αN = Nω N−1 (ωN−1 is the surface area of the unit sphere in RN ), and αN is defined by exp(ξ) − N−2 ∑ j=0 1 j! ξ.
Abstract: We study Trudinger type inequalities in RN and their best exponents αN . We show for α ∈ (0, αN ), αN = Nω N−1 (ωN−1 is the surface area of the unit sphere in RN ), there exists a constant Cα > 0 such that ∫ RN ΦN α( |u(x)| ‖∇u‖LN (RN ) ) N N−1  dx ≤ Cα ‖u‖NLN (RN ) ‖∇u‖N LN (RN ) (∗) for all u ∈W 1,N (RN ) \ {0}. Here ΦN (ξ) is defined by ΦN (ξ) = exp(ξ) − N−2 ∑ j=0 1 j! ξ . It is also shown that (∗) with α ≥ αN is false, which is different from the usual Trudinger’s inequalities in bounded domains. 0. Introduction In this note, we study the limit case of Sobolev’s inequalities; suppose N ≥ 2 and let D ⊂ R be an open set. We denote by W 1,N 0 (D) the usual Sobolev space, that is, the completion of C∞ 0 (D) with the norm ‖u‖W 1,p 0 (D) = ‖∇u‖p+‖u‖p. Here ‖u‖p = (∫

284 citations

Journal ArticleDOI
TL;DR: Analysis of the complex dielectric and Raman spectra of hydrogen-bond liquids in the microwave to terahertz frequency range indicates that the cooperative relaxation, accompanied by huge polarization fluctuation, is virtually not Raman active, whereas the faster processes reflect common microscopic dynamics.
Abstract: We analyzed the complex dielectric and Raman spectra of hydrogen-bond liquids in the microwave to terahertz frequency range. As for water and methanol, the high-frequency component of the dielectric spectrum, i.e., the small deviation from the principal Debye relaxation, clearly corresponds to the Raman spectrum. This indicates that the cooperative relaxation, accompanied by huge polarization fluctuation, is virtually not Raman active, whereas the faster processes reflect common microscopic dynamics. For ethylene glycol, the shape of the Raman spectrum also resembles that of the high-frequency deviation of the dielectric spectrum, but, additionally, a weak manifestation of the cooperative relaxation arising from quadrupolar conformers is detected.

284 citations

Journal ArticleDOI
A. A. Abdo1, A. A. Abdo2, Markus Ackermann3, Marco Ajello3  +204 moreInstitutions (36)
TL;DR: In this paper, the gamma-ray flux of 14 dwarf spheroidal galaxies with the Fermi Gamma-Ray Space Telescope taken during the first 11 months of survey mode operations was determined, assuming both powerlaw spectra and representative spectra from WIMP annihilation.
Abstract: We report on the observations of 14 dwarf spheroidal galaxies with the Fermi Gamma-Ray Space Telescope taken during the first 11 months of survey mode operations. The Fermi telescope provides a new opportunity to test particle dark matter models through the expected gamma-ray emission produced by pair annihilation of weakly interacting massive particles (WIMPs). Local Group dwarf spheroidal galaxies, the largest galactic substructures predicted by the cold dark matter scenario, are attractive targets for such indirect searches for dark matter because they are nearby and among the most extreme dark matter dominated environments. No significant gamma-ray emission was detected above 100 MeV from the candidate dwarf galaxies. We determine upper limits to the gamma-ray flux assuming both power-law spectra and representative spectra from WIMP annihilation. The resulting integral flux above 100 MeV is constrained to be at a level below around 10^-9 photons cm^-2 s^-1. Using recent stellar kinematic data, the gamma-ray flux limits are combined with improved determinations of the dark matter density profile in 8 of the 14 candidate dwarfs to place limits on the pair annihilation cross-section of WIMPs in several widely studied extensions of the standard model. With the present data, we are able to rule out large parts of the parameter space where the thermal relic density is below the observed cosmological dark matter density and WIMPs (neutralinos here) are dominantly produced non-thermally, e.g. in models where supersymmetry breaking occurs via anomaly mediation. The gamma-ray limits presented here also constrain some WIMP models proposed to explain the Fermi and PAMELA e^+e^- data, including low-mass wino-like neutralinos and models with TeV masses pair-annihilating into muon-antimuon pairs. (Abridged)

283 citations


Authors

Showing all 24378 results

NameH-indexPapersCitations
Yusuke Nakamura1792076160313
Yoshio Bando147123480883
Charles Maguire142119795026
Kazunori Kataoka13890870412
Senta Greene134134690697
Intae Yu134137289870
Kohei Yorita131138991177
Wei Xie128128177097
Susumu Kitagawa12580969594
Leon O. Chua12282471612
Jun Kataoka12160354274
S. Youssef12068365110
Katsuhiko Mikoshiba12086662394
Yusuke Yamauchi117100051685
Teruo Okano11747647081
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Performance
Metrics
No. of papers from the Institution in previous years
YearPapers
202380
2022237
20212,347
20202,467
20192,367
20182,289