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排序方式: 共有1449条查询结果,搜索用时 296 毫秒
821.
822.
We have carried out thermal expansion measurements on the heavy fermion compound URu2Si2. We have discovered a new anomaly that appears only under pressure for both the tetragonal a and c axes. Plotting these temperatures on a temperature-pressure plane, we have constructed a phase diagram, in which there is a first order phase transition boundary separating a hidden and antiferromagnetic order. When the system enters the antiferromagnetic phase from the hidden order, the lattice constant shrinks along the a axis and elongates along the c axis, leading to an increase in the lattice constant ratio of c/a. We conclude that the system lies close to a bicritical point from which the first order phase transition line emanates. 相似文献
823.
Image super-resolution based on local self-similarity 总被引:4,自引:0,他引:4
A new image super-resolution method based on a codebook mapping is proposed. The codebook mapping represents the internal
relationship between low-and high-frequency image components, and is used for the estimation of highfrequency image components
lost in the sampling process. In the proposed method, codebooks are first generated by the low-and high-frequency image components
of the original image itself that is to be processed. Then, a resultant superresolution image, that is, an enlarged image,
is obtained by combining the estimated high-frequency image components with the low-frequency ones obtained by a typical interpolation-based
method. The effectiveness of the proposed method is verified by comparing it against some conventional methods. 相似文献
824.
M. Ukai S. Ajimura H. Akikawa D. E. Alburger A. Banu R. E. Chrien G. B. Franklin J. Franz O. Hashimoto T. Hayakawa H. Hotchi K. Imai T. Kishimoto M. May D. J. Millener S. Minami Y. Miura T. Miyoshi K. Mizunuma T. Nagae S. N. Nakamura K. Nakazawa Y. Okayasu P. Pile B. P. Quinn A. Rusek Y. Sato R. Sutter H. Takahashi L. Tang H. Tamura K. Tanida L. Yuan S. H. Zhou 《The European Physical Journal A - Hadrons and Nuclei》2007,33(3):247-250
We have observed three γ -ray transitions in Λ
16 O from both 7MeV excited spin-flip and non-spin-flip partners ( 2-, 1-
2 to the ground-state doublet ( 1-
1, 0- via the 16O(K
-,π-) reaction. The 7MeV excitation energies of the spin-doublet members ( 2-, 1-
2 were determined to be 6784±4±4 keV and 6562±1±2 keV, respectively, and thus the spacing was obtained to be 222±4±5 keV.
This is the first observation of the spin-flip state directly populated by the ( K
-,π- reaction. Moreover, such directly populated spin-flip and non-spin-flip partners were resolved for the first time. 相似文献
825.
T. Maruta S. Ajimura K. Aoki A. Banu H. Bhang T. Fukuda O. Hashimoto I. Hwang S. Kameoka B. H. Kang E. H. Kim J. H. Kim M. J. Kim Y. Miura Y. Miyake T. Nagae M. Nakamura S. N. Nakamura H. Noumi S. Okada Y. Okayasu H. Outa H. Park P. K. Saha Y. Sato M. Sekimoto T. Takahashi H. Tamura K. Tanida A. Toyoda K. Tsukada T. Watanabe 《The European Physical Journal A - Hadrons and Nuclei》2007,33(3):255-258
The proton decay asymmetry, αNM
p , of the polarized Λ -hypernuclei, 5
ΛHe , 12
ΛC and 11
ΛB , has been investigated to understand the reaction mechanism of the non-mesonic weak-decay process. These Λ -hypernuclei
were produced in the highest statistics ever via the (π+, K
+) reaction at 1.05GeV/c by using the SKS spectrometer at KEK 12GeV PS. The results show that the αNM
p are very small for these s -shell and p -shell hypernuclei. 相似文献
826.
827.
Noriaki Kimura 《Journal of Number Theory》1979,11(2):171-187
A proof is given of congruences of the Kummer type for generalized Bernoulli numbers associated with the primitive residue character χ mod f, in particular when the conductor of χ is a power of a prime, which is the main purpose of this paper. 相似文献
828.
The reaction of 2-t-butyl-1,3-butadiene with π-allylic palladium chlorides is described. The 2-chloroallyl complex gives a π-allylic complex with an open chain structure, in which the butenyl group in is the anti-position. Allyl-1-carbomethoxyallyl-, methallyl-, and 1-carbomethoxymethallyl-palladium chlorides give six-membered cyclic complexes. The product of the former two are π-allyllic and those of the latter are σ-bonded complexes. 相似文献
829.
Mitsuru Okigawa Takeyoshi Nakayama Kazuyoshi Takayama Noriaki Itoh 《Solid State Communications》1984,49(4):347-349
The damage of surface layers of GaAs induced by a laser pulse with 15 ns and 600 ns duration has been studied by means of channeling. It is found that damage induced by 600 ns pulses is much more pronounced than that by shorter pulses and that 600 ns pulses produce As-rich layers at the surface. Results are discussed on the basis of calculated temperature rise during and after a laser pulse. 相似文献
830.