Application of Brillouin scattering to the local anisotropy and birefringence measurements of thin layers

Brillouin scattering is an efficient nondestructive and noncontact measurement method to obtain the wave properties of thin layers at hypersonic frequencies. The reflection induced ThetaA (RIThetaA) scattering geometry enables the simultaneous measurement of the phonons, which propagate in each direction of wave vectors of q(Theta A) (propagation in the film plane) and q(180) (back scattering). Using this scattering geometry, we could observe the refractive indices and birefringence of the piezoelectric poly-vinylidene fluoride (PVDF) film as a function of temperature. By introducing the microscopic technique, the elastic anisotropy and refractive index measurements in the minute area of polycrystalline ZnO films were also performed.     

Synthesis of a proposed biosynthetic intermediate of a marine cyclic ether brevisamide for study on biosynthesis of marine ladder-frame polyethers

A monocyclic ether alkaloid, brevisamide (1) was isolated from the dinoflagellate Karenia brevis that produces a variety of ladder-frame polyethers. Its proposed biosynthetic intermediate (2) comprising a linear backbone with an E-olefin functionality was synthesized for biosynthetic studies on the marine ladder-frame polyethers.     

A cyclic glucosyl ceramide acceptor as a versatile building block for complex ganglioside synthesis

A cyclic glucosyl ceramide (GlcCer) acceptor has been developed as a versatile building block for the synthesis of complex ganglioside. A macrocyclic GlcCer acceptor, which was the product of intramolecular glycosylation between glucose and ceramide, exhibited high reactivity during the coupling reactions with a variety of complex oligosaccharyl donors, thereby furnishing the corresponding ganglioside frameworks in high yields.     

Modification of flexible part in Cu(2+) interdigitated framework for CH(4)/CO(2) separation

The structural flexibility of Cu(2+) interdigitated layer type framework was controlled and the compound represented clear separation property of CH(4)/CO(2) at range of 0-1.0 MPa and recovery of adsorbed CO(2) above 0.1 MPa.     

Ultrafast photosynthetic reduction of elemental sulfur by Au nanoparticle-loaded TiO2

Nanometer-sized gold particles with varying mean size from 3.2 to 12.2 nm were loaded on the surfaces of TiO2 particles in a highly dispersed state with the loading amount maintained constant (0.46 +/- 0.02 mass %) using the deposition-precipitation method. Light irradiation (lambda(ex) > 300 nm) to a deaerated ethanol TiO2 particle suspension containing elemental sulfur (S8) led to the energetically uphill reduction of S8 to H2S. It has been found that this reaction is dramatically enhanced with such a low level of Au loading on TiO2 and that the zero-order rate constant of reaction increases with decreasing mean size of Au nanoparticles (d). The effects of reaction parameters (substrate concentration, light intensity, temperature) on the rate of reaction were studied to infer the essential reaction mechanism. Further, a kinetic analysis has led to a conclusion that the increase in the rate of reaction with decreasing d results from the improvement of the charge separation efficiency.     

Polymorphism of Supramolecular Charge-Transfer Complex Composed of 10,10′-dihydroxy-9,9′-biphenanthryl and p-benzoquinone

Charge-transfer (CT) complexes were prepared using racemic (rac)-10,10′-dihydroxy-9,9′-biphenanthryl, which has a large and highly π-conjugated phenanthrene ring, as the electron donor and p-benzoquinone as the electron acceptor. This CT system showed a polymorphism.     

Phase-transition phenomena of 0.8 microm superfluid 3He slab

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.     

A note on the paper by Bugeaud and Laurent “Minoration effective de la distance p-adique entre puissances de nombres algébriques”

We shall make a slight improvement to a result of p-adic logarithms, which gives a nontrivial upper bound for the exponent of p dividing the Fermat quotient xp−1−1.