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991.
A. Ishida Y. Makishima A. Okada I. Akai K. Kanemoto T. Karasawa M. Kimura J. Takeda 《Journal of luminescence》2008,128(5-6):771-773
Rapid energy transfer dynamics in light-harvesting small dendrimers (star-shaped stilbenoid phthalocyanine: SSS1-Pc) having oligo (p-phenylenevinylene) peripheries was studied by real-time pump-probe imaging spectroscopy implemented on a single-shot basis. Using this method, we could successfully map the time–frequency two-dimensional (2D) image of the transient absorption of SSS1-Pc with a very short accumulation time. Under the selective excitation of the peripheries, the 2D image obtained clearly shows the transient absorption as well as the ground-state bleaching due to the energy transfer to the core with a fast rise time of ~0.3 ps. This fast rise implies that the rapid energy transfer from the peripheries to the core takes place through the short-range interactions due to the overlap of wave functions between the excited states of the peripheries and the core. 相似文献
992.
Tohru Koma 《Journal of statistical physics》1993,71(1-2):269-297
We propose a new Monte Carlo method for calculating eigenvalues of transfer matrices leading to free energies and to correlation lengths of classical and quantum many-body systems. Generally, this method can be applied to the calculation of the maximum eigenvalue of a nonnegative matrix  such that all the matrix elements of Âk are strictly positive for an integerk. This method is based on a new representation of the maximum eigenvalue of the matrix  as the thermal average of a certain observable of a many-body system. Therefore one can easily calculate the maximum eigenvalue of a transfer matrix leading to the free energy in the standard Monte Carlo simulations, such as the Metropolis algorithm. As test cases, we calculate the free energies of the square-lattice Ising model and of the spin-1/2XY Heisenberg chain. We also prove two useful theorems on the ergodicity in quantum Monte Carlo algorithms, or more generally, on the ergodicity of Monte Carlo algorithms using our new representation of the maximum eigenvalue of the matrixÂ. 相似文献
993.
Shojiro Kimura Hitoshi Ohta Mitsuhiro Motokawa Seitaro Mitsudo Wen-Jye Jang Masahi Hasegawa Humihiko Takei 《International Journal of Infrared and Millimeter Waves》1996,17(5):833-841
Submillimeter wave ESR system in Kobe University is presented. It covers the frequency region from 60 to 383GHz and can apply the pulsed magnetic field up to 30T. The measurement of Y2Cu2O5 single crystals using our system is presented. 相似文献
994.
Separation of epimeric 24-isopropenylcholesterols () was effectively achieved by reversed-phase HPLC. The C-24 stereochemistry of these epimers was determined on the basis of chemical and spectroscopic evidence. 相似文献
995.
Takashi Kimura Jim Stasheff Alexander A. Voronov 《Communications in Mathematical Physics》1995,171(1):1-25
We construct a real compactification of the moduli space of punctured rational algebraic curves and show how its geometry yields operads governing homotopy Lie algebras, gravity algebras and Batalin-Vilkovisky algebras. These algebras appeared recently in the context of string theory, and we give a simple deduction of these algebraic structures from the formal axioms of conformal field theory and string theory.To the memory of Ansgar SchnizerResearch supported by an NSF Postdoctoral Research FellowshipResearch supported in part by NSF grant DMS-9206929 and a Research and Study Leave from the University of North Carolina-Chapel HillResearch supported in part by NSF grant DMS-9108269.A03 相似文献
996.
997.
Tohru Eguchi Shinobu Hosono Sung-Kil Yang 《Communications in Mathematical Physics》1991,140(1):159-168
We point out that bosonic conformal coset modelsG
l
×G
k
/G
l+k
for all semi-simple Lie algebrasG have a hidden fermionic symmetry atl=0 (the central charge=0) and may be interpreted as twisted versions of some superconformal theories. 相似文献
998.
J. Tanaka K. Nomura Y. Ujihira A. Vértes H. Kimura T. Masumoto 《Hyperfine Interactions》1990,55(1-4):1071-1075
Amorphous Fe90Zr10 and Fe91Hf9 ribbons were charged with hydrogen by the electrochemical method up to Fe90Zr10H26 and Fe91Hf9H15, respectively, and the change in magnetic structures were analyzed by Mössbauer spectrometry. The internal magnetic field appeared by the charge of hydrogen, the degree of change being depended on amounts of hydrogen included in amorphous Fe90Zr10 and Fe91Hf9, although Fe91Hf9 absorbed hydrogen more slowly than Fe90Zr10. The differences of hydrogen inclusion and Mössbauer hyperfine structure between Fe90Zr10 and Fe91Hf9 were discussed based on the results of a hyperfine field distribution and the radial distribution functions of Fe?Fe obtained by EXAFS. 相似文献
999.
1000.
As an application of a TBP/XAD-4 column for the analytical separation of uranium, neptunium, plutonium and americium, the elution behavior of these elements as a function of their redox reactions has been studied. Subsequently, two effective procedures to carry out a quantitative separation of the actinide elements from each other were established by combining extraction chromatography in the TBP-HNO3 system and the redox reactions of the actinide elements. 相似文献