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941.
Kawasaki K Yoshida T Tarui M Nakagawa H Yano H Ishikawa O Hata T 《Physical review letters》2004,93(10):105301
We have investigated the transition phenomena of superfluid 3He in thin 0.8 microm slabs with a cw-NMR method. We found that, just below the phase-transition temperature, only the A phase appeared at any pressure. At lower temperatures, the phase transition to the B phase occurred between 0.3 and 2.74 MPa. We obtained a universal critical thickness delta as a function of pressure. When the reduced slab thickness, d/xi(T), is smaller than delta, only the A phase becomes stable. 相似文献
942.
Yoshida H Nobusada K Okada K Tanimoto S Saito N De Fanis A Ueda K 《Physical review letters》2002,88(8):083001
Symmetry-resolved excitation spectra have been measured for the Renner-Teller pair states A(1) and B(1) split from the core-excited C 1s(-1)2 pi(u) state in CO(2). A vibrational progression with the spacings of approximately 145 meV is found in both the A(1) and B(1) spectra at different energies and assigned to the symmetric stretching mode caused in the B(1) linear state, with the help of ab initio calculations. Appearance of the vibrations in the A(1) spectrum is interpreted as due to non-adiabatic coupling between the A(1) and B(1) states via the bending motion. 相似文献
943.
Tonomura A Kasai H Kamimura O Matsuda T Harada K Yoshida T Akashi T Shimoyama J Kishio K Hanaguri T Kitazawa K Masui T Tajima S Koshizuka N Gammel PL Bishop D Sasase M Okayasu S 《Physical review letters》2002,88(23):237001
In order to elucidate the formation mechanism of unconventional arrangements of vortices in high- Tc superconducting thin films at an inclined magnetic field to the layer plane, we investigated the structures of vortex lines inside the films by Lorentz microscopy using our 1-MV field-emission electron microscope. Our observation results concluded that vortex lines are tilted to form linear chains in YBaCu3O(7,8). Vortex lines in the chain-lattice state in Bi2Sr2CaCu2O(8+delta), on the other hand, are all perpendicular to the layer plane, and therefore only vortices lined up along Josephson vortices form chains. 相似文献
944.
Racemic indanofan [(+/-)-1] was efficiently converted to enantiopure (S)-indanofan [(S)-1] by a combination of enzymatic resolution and chemical inversion techniques. An additional important technique is the use of an o-xylene complex of a hemiketal (S)-3c as a precursor, which can be quantitatively converted to (S)-indanofan and easily purified by recrystallization from o-xylene. 相似文献
945.
Iwaura R Ohnishi-Kameyama M Yoshida M Shimizu T 《Chemical communications (Cambridge, England)》2002,(22):2658-2659
Complementary base paired complex formation of a thymidine-appended bolaamphiphile with adenosine derivatives was able to be detected with high resolution and high sensitivity in aqueous solutions by electrospray ionization-Fourier-transform ion cyclotron resonance mass (ESI-FTICR MS) spectrometry. 相似文献
946.
Kapoor MP Sinha AK Seelan S Inagaki S Tsubota S Yoshida H Haruta M 《Chemical communications (Cambridge, England)》2002,(23):2902-2903
Gold nanoparticles supported on highly hydrophobic ethane bridged Ti incorporated mesoporous organosilica are reported for enhanced vapor phase epoxidation of propene using H2 and O2. 相似文献
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[reaction: see text] Pharmacologically important diarylmethane structures have been prepared in a straightforward manner through sequentially integrated Pd-catalyzed cross-coupling reactions. (2-Pyridyl)silylmethylstannane was found to be an air-stable, storable, and versatile coupling platform in this synthetic strategy. 相似文献