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211.
Tomo Takahashi Masahide Yamaguchi Jun'ichi Yokoyama Shuichiro Yokoyama 《Physics letters. [Part B]》2009
We investigate density fluctuations in a scenario with gravitino dark matter in the framework of modulated reheating, which is known to generate large non-Gaussianity. We show that gravitino dark matter is disfavored in this framework. We also briefly discuss the case with the curvaton mechanism and some other possible dark matter scenarios. 相似文献
212.
Nishihara Y Sakakura M Kimura Y Terazima M 《Journal of the American Chemical Society》2004,126(38):11877-11888
The carbon monoxide (CO) docking sites involved in the ligand escape process from the iron atom in hem of myoglobin (Mb) to solution at physiological temperature were studied on the basis of the effect of xenon (Xe) on the ligand escape rate by the transient grating (TG) technique. The TG method provides a direct measurement of the changes in molecular volume. The apparent CO escaping rate and the volume contraction increase with increasing Xe pressure. The pressure dependence of the rate is consistent with that of the Xe population at the Xe(1) site. This result clearly shows that CO is trapped at the Xe(1) site before escaping to solvent in a Xe-free solution at room temperature. It is shown that only CO but not the trapped Xe is released by the photoexcitation of the Xe-trapped MbCO. A dissociation scheme is proposed to explain the enhancement of the escaping rate by the presence of Xe(1). There are two branches for the CO escaping pathway. The dominant part of the dissociated CO escapes to the solvent through the Xe(1) trapping site under the Xe-free condition, and there are at least three intermediate states along this pathway. When a Xe atom blocks the Xe(1) site, the CO escapes through another route. 相似文献
213.
The coincidence L3 and M3 photoelectron spectroscopy (PES) main lines of Cu metal are calculated by a many-body theory. There is no peak-energy shift between the singles PES main line and the coincidence one. The asymmetric narrowing of the coincidence PES main line on the low kinetic energy (KE) side is very small. This is in accord with recent experimental findings. In Cu metal, the shakeup satellite intensity is small and the main-line satellite separation energy is much larger than the core–hole lifetime width. The interference via the final-state interaction is negligible. In the PES main line, the imaginary part of the self-energy by shakeup excitations, which is very small compared to the core–hole lifetime width, decreases very slowly in linear with photoelectron KE. The branching ratio of Auger decay of a single hole state then increases very slowly in linear with photoelectron KE so that the deviation of the coincidence PES main line from the singles one is very small. The 939 eV structure seen only in the coincidence L3 PES spectrum of Cu metal is attributed to the enhancement of the inelastic peak of a smaller energy loss due to electrons of a smaller average emission depth measured in coincidence with the elastic Auger peak. The structure will not be enhanced in the singles PES spectrum. The background subtraction in the coincidence spectrum cannot be the same as that in the singles one. Such consideration is necessary before we can conclude about the asymmetric narrowing on the low KE side. A unique capability of APECS by which one can determine the photoelectron KE dependent part of the imaginary part of the self-energy is pointed out. 相似文献
214.
215.
216.
Masahide Kuwada 《Annals of the Institute of Statistical Mathematics》1986,38(1):343-351
Summary This paper investigates some partially balanced fractional 2
m
1+m
2 factorial designs of resolution IV derived from partially balanced arrays, which permit estimation of the general mean, all
main effects, all two-factor interactions within each set of them
k
factors (k=1, 2) and some linear combinations of the two-factor interactions between the sets of them
k
ones. In addition, optimal designs with respect to the generalized trace criterion defined by Shirakura (1976,Ann. Statist.,4, 723–735) are presented for each pair (m
1,m
2) with 2≦m
1≦m
2 andm
1+m
2≦6, and for values ofN (the number of observations) in a reasonable range.
Partially supported in part by Grants 56530009 (C) and 57530010 (C). 相似文献
217.
Masahide Itoh Ryuji Yamada Ronglong Tian Minghong Tsai Toyohiko Yatagai 《Optical Review》1995,2(2):135-138
The absolute longitudinal distance between two points can be determined by the corresponding correlation peaks of two light-waves from a broad-band light source. Using this technique, the height of three-dimensional objects can be measured without 2π phase ambiguity. We can also detect the absolute position of scattering seeds in sub-surface or bulk materials such as defects, dislocations or impurities of high purity materials. The wavelet analysis is used to determine the correlation peaks. This technique can be applied to measurement of thickness of a few hundred microns.Presented at the International Commission for Optics Topical Meeting, Kyoto, 1994. 相似文献
218.
Kusama H Funami H Shido M Hara Y Takaya J Iwasawa N 《Journal of the American Chemical Society》2005,127(8):2709-2716
Novel tungsten-containing carbonyl ylides 7, generated by the reaction of the o-alkynylphenyl carbonyl derivatives 1 with a catalytic amount of W(CO)(5)(thf), reacted with alkenes to give polycyclic compounds 5 through [3 + 2]-cycloaddition reaction followed by intramolecular C-H insertion of the produced nonstabilized carbene complex intermediates 8. In the presence of triethylsilane, these tungsten-containing carbene intermediates 8 were smoothly trapped intermolecularly by triethylsilane to give silicon-containing cycloadducts 17 with regeneration of the W(CO)(5) species. By this procedure, the scope of alkenes employable for this reaction was clarified. The presence of the tungsten-containing carbonyl ylide 7c was confirmed by direct observation of the mixture of o-ethynylphenyl ketone 1c and W(CO)(5)(thf-d(8)). Careful analysis of the intermediate by 2D NMR, along with the observation of the direct coupling with tungsten-183 employing the (13)C-labeled substrate, confirmed the structure of the ylide 7c. Examination using (E)- or (Z)- vinyl ether revealed that the [3 + 2]-cycloaddition reaction proceeded in a concerted manner and that the facial selectivity of the reaction differed considerably depending on the presence or absence of triethylsilane. These results clarified the reversible nature of this [3 + 2]-cycloaddition reaction. 相似文献
219.
Isao Yamada Kakuei Matsubara Mitsuharu Kodama Masahide Ozawa Toshinori Takagi 《Journal of Crystal Growth》1978
The main characteristics of the metal films deposited by ionized-cluster beam deposition and their applications are described. These films showed good adhesion, high packing density, good conductivity, and unique diffusion characteristics of the deposited material onto Si substrates. These advantages have been utilized in fabricating electron devices such as flexible circuits, solar cells, and ohmic contacts. 相似文献
220.
Yoshiki Katayama Kazuhide Nita Masahide Ueda Hiroshi Nakamura Makoto Takagi Keihei Ueno 《Analytica chimica acta》1985
New crown ethers carrying a pendent phenolic chromophore were synthesized. These crown ethers, on dissociation of the phenolic proton, provide lipophilic anions which can extract alkali metal cations into 1,2-dichloroethane by forming highly-colored uncharged metal complexes. Structural effects on the extraction were studied for possible use of these crown ethers as extraction—spectrophotometric reagents selective for alkali metals. The following factors are discussed in detail: (i) nature of the crown ether ring (ring size. aza-crown or standard crown ether), (ii) nature of the pendent phenolic group, and (iii) geometry between the crown ether center and pendent phenolic group. 15-Crown-5 or smaller ring-sized reagents favored the extraction of lithium ion when the basicity of the pendent phenolate was relatively high and a six-membered “chelate” ring was possible for the phenolate and the crown ether-bound metal. 15-Crown-5 type reagents were sodium-selective when an eight-membered “chelate” ring was possible between the phenolate and the crown ether-bound metal. 18-Crown-6 type reagents were generally potassium-selective. However, these selectivities were not absolute, and other structural parameters, steric and conformational, must be considered to explain in detail the selectivities of the individual reagents. 相似文献