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331.
We have investigated the dynamical properties of the coherent anharmonic phonons generated in Bi under high density excitation. The time-resolved reflectivity in the intensely photoexcited Bi film is modulated by the coherent A(1g) phonon oscillation with a time-dependent oscillation period. As the pump power density is increased, the line shape of the A(1g) mode in the Fourier transformed spectra becomes asymmetric, and the redshift of the phonon frequency is observed. Analysis of the transient redshift with a wavelet transform reveals that the frequency of the A(1g) mode depends on the squared amplitude of the oscillation, which is attributed to an anharmonicity of the lattice potential. 相似文献
332.
By using estimates on the frequency of large values of the Riemann zeta-function and modular L-functions attached to the full modular group SL(2, ℤ), we prove sharp upper and lower estimates of the mean square of standard L-functions attached to Siegel cusp forms which are Ikeda lifts, on boundaries and the central line of the critical strip.
The mean square of spinor L-functions attached to Saito-Kurokawa lifts is also studied. 相似文献
333.
334.
Yoshiya Shinagawa Yasuko Shinagawa Nobuhiro Uyesaka Kohji Fukuda 《International journal of quantum chemistry》1980,18(2):357-363
The spin densities of the radical anions from 4-methylcatechol, 4-carboxylic catechol, and 3-methylcatechol were calculated by means of the INDO method with the geometrical parameter adjusting method. The observed protion hyperfine coupling constants were exactly reproduced. 相似文献
335.
336.
Yuui Yokota Jun-ichi Shimoyama Tetsuro Ogata Shigeru Horii Kohji Kishio 《Solid State Communications》2007,142(8):429-433
We have examined the effects of excess oxygen on the magnetization, electrical transport properties and crystal structure of La0.95Sr0.05MnOy. An antiferromagnetic insulator phase confirmed in the as-grown crystal at low temperatures changed to a ferromagnetic insulator phase after the introduction of excess oxygen. The ferromagnetic transition temperature, TC, systematically increased with increasing oxygen content, y, due to an increase in the mean valence of manganese. However, the TC of crystals with excess oxygen was lower than that of the La1−xSrxMnO3.00 having identical manganese valence. This is considered to be a result of the competition among the mean valence of manganese, the concentration of cation vacancies, and the mean ionic radius of cations at the A-site. 相似文献
337.
338.
Reaction with 1,8-diazabicyclo[5,4,0]undec-7-ene (DBU) of 2-[3-(p-tolylsulfonyl)-2-propenyl]-2-carboethoxycycloalkanones, derived from 2-carboethoxy-2-sodiocycloalkanones and 3-bromo-l-(p-tolylsulfonyl)propene, caused ring opening three-carbon extension in ethanol and three-carbon ring expansion in benzene to produce terminal dienes and cyclic dienes, respectively. 相似文献
339.
340.
Fujioka S Nishimura H Nishihara K Sasaki A Sunahara A Okuno T Ueda N Ando T Tao Y Shimada Y Hashimoto K Yamaura M Shigemori K Nakai M Nagai K Norimatsu T Nishikawa T Miyanaga N Izawa Y Mima K 《Physical review letters》2005,95(23):235004
Opacity effects on extreme ultraviolet (EUV) emission from laser-produced tin (Sn) plasma have been experimentally investigated. An absorption spectrum of a uniform Sn plasma generated by thermal x rays has been measured in the EUV range (9-19 nm wavelength) for the first time. Experimental results indicate that control of the optical depth of the laser-produced Sn plasma is essential for obtaining high conversion to 13.5 nm-wavelength EUV radiation; 1.8% of the conversion efficiency was attained with the use of 2.2 ns laser pulses. 相似文献