Global solutions for the Navier-Stokes equations in the rotational framework

The existence of global unique solutions to the Navier-Stokes equations with the Coriolis force is established in the homogeneous Sobolev spaces $\dot{H}^s (\mathbb R ^3)^3$ for $1/2 < s < 3/4$ if the speed of rotation is sufficiently large. This phenomenon is so-called the global regularity. The relationship between the size of initial datum and the speed of rotation is also derived. The proof is based on the space time estimates of the Strichartz type for the semigroup associated with the linearized equations. In the scaling critical space $\dot{H}^{\frac{1}{2}} (\mathbb R ^3)^3$ , the global regularity is also shown.     

Improvement of Cu2ZnSnS4 thin film morphology using Cu–Zn–Sn–O precursor fabricated by sputtering

The new precursor of Cu–Zn–Sn–O (CZTO) was proposed for Cu₂ZnSnS₄ (CZTS) thin film fabrication to improve film morphology. The CZTS thin film grown from Cu–Zn–Sn (CZT) precursors has many bumps. We deposited CZTO precursors on Mo/soda-lime glass (SLG) substrates by RF sputtering using a CZT (Cu:Zn:Sn = 2:1:1) target in Ar and O₂ atmosphere at various O₂ partial pressures (0%, 5%, 17% and 20%). Subsequently, the CZTO precursors were sulfurized in Ar and S atmosphere to fabricate CZTS thin films. The CZTO precursors were amorphous. The morphology of the CZTS thin films was improved by the CZTO precursors. All of the CZTS films fabricated in this study had the same crystal structure. Composition analysis revealed that 50% of O were detected in the CZTO precursor, but O was not detected after sulfurizing process, indicating that O was substituted by S. The CZTS thin film from the CZTO precursor fabricated at O₂ partial pressure of 20% had similar composition for solar cell absorber.     

Measurement of all Deuteron Analyzing Powers for {\overrightarrow{d} + p} Elastic Scattering at 294 MeV/Nucleon

We have measured all deuteron analyzing powers ${(A_{y}^{d}, A_{yy}, A_{xx}, A_{xz})}$ for deuteron-proton elastic scattering at 294 MeV/nucleon in order to study the properties of three nucleon forces (3 NFs). Measurement was made at in an angular range of ${\theta_{{\rm c.m.}} = 35.6^{\circ} - 163.0^{\circ}}$ . Obtained data were compared with Faddeev calculations with and without the 3 NFs. At ${\theta_{{\rm c.m.}}\lesssim 120^{\circ}}$ all the data have general agreement with the calculations, while the measured data at ${\theta_{{\rm c.m.}} \gtrsim 120^{\circ}}$ are not explained by any theoretical calculations. These results were consistent with those at 250 MeV/nucleon.     

Analysis of oligomeric transition of silkworm small heat shock protein sHSP20.8 using high hydrostatic pressure native PAGE

The small heat shock proteins (sHSPs) solubilize thermo-denatured proteins without adenosine triphosphate energy consumption to facilitate protein refolding. sHSP20.8 is one of the silkworm (Bombyx mori) sHSPs having only one cystein in the N-terminal domain: Cys43. We report a simple measurement of oligomeric transition of sHSP20.8 using high hydrostatic pressure native polyacrylamide gel electrophoresis (high hydrostatic pressure (HP) native polyacrylamide gel electrophoresis (PAGE)). At ambient pressure under oxydative condition, the native PAGE of thermal transition of sHSP20.8 oligomer displayed a cooperative association. In contrast, HP native PAGE clearly demonstrated that sHSP20.8 dissociated at 80 MPa and 25°C, and the resultant molecular species gradually reassociated with time under that condition. In addition, the reassociation process was suppressed in the presence of the reductant. These results are consistent with the idea that sHSP20.8 oligomer temporally dissociates at the first thermo-sensing step and reassociates with the oxidation of Cys43.     

Evaluation of the thermal effect on separation selectivity in anion-exchange processes using superheated water ion-exchange chromatography

The thermal effect on retention and separation selectivity of inorganic anions and aromatic sulfonate ions in anion-exchange chromatography is studied on a quaternized styrene-divinylbenzene copolymer anion-exchange column in the temperature range of 40-120 °C using superheated water chromatography. The selectivity coefficient for a pair of identically charged anions approaches unity as temperature increases provided the ions have the same effective size, such that the retention of an analyte ion decreases with an increase in temperature when the analyte ion has stronger affinity for the ion-exchanger than that of the eluent counterion, whereas it increases when it has weaker affinity. The change in anion-exchange selectivity with temperature observed with superheated water chromatography has been discussed on the basis of the effect of temperature on hydration of the ions. At elevated temperatures, especially in superheated water, the electrostatic interaction or association of the ions with the fixed ion in the resin phase becomes a predominant factor resulting in a different separation selectivity from that obtained at ambient temperature.     

Topological Difference in 2D Layers Steers the Formation of Rigid and Flexible 3D Supramolecular Isomers: Impact on the Adsorption Properties

Starting with the same precursors, pyridine-2,3-dicarboxylate (pyrdc) and 4,4'-bipyridyl (bipy), two 3D porous coordination polymers, {[Cu(bipy)(0.5)(pyrdc)]·3H(2)O} (1) and {[Cu(bipy)(0.5)(pyrdc)]·0.5bipy·3H(2)O} (2), have been synthesized by changing the solvent system from MeOH/H(2)O to EtOH/H(2)O. Single-crystal structure analysis revealed that 1 and 2 are supramolecular isomers with 3D pillared-layer structures having 1D channel systems. Isomer 1 has a flexible structure and shows gated adsorption behavior, while framework 2 has a rigid backbone and exhibits the adsorption properties of typical microporous materials.     

Concise enantioselective synthesis of duloxetine via direct catalytic asymmetric aldol reaction of thioamide

Direct catalytic asymmetric aldol reaction of thioamide offers a new entry to the concise enantioselective synthesis of duloxetine. The direct aldol protocol was scalable (>20 g) to afford the aldol product in 92% ee after LiAlH(4) reduction, and 84% of the chiral ligand was recovered after recrystallization. The following four steps of transformation delivered duloxetine.     

Improved stability of organic field-effect transistor performance in oligothiophenes including β-isomers

Dialkyl quarter- and quinquethiophenes end-capped with β-connected thiophenes are prepared, and the field-effect transistor (FET) properties are investigated. Molecular orbital calculation as well as the redox and optical measurements indicate that the β-isomers have low-lying HOMO levels and large energy gaps compared with the α-isomers. Molecular packing of the dihexylquaterthiophene with β-isomers consists of a typical herringbone motif analogous to the α-isomers. In the single crystal, the alkyl chains are extending in the tilted directions from the core molecular plane, but straightly extending in the thin films, resulting in even more perpendicular molecular arrangement to the substrate than the α-isomers. These β-isomers show p-type FET performance comparable to the corresponding α-isomers, whereas all new oligothiophenes show air stability better than the corresponding α-isomers. In particular, dihexylquinquethiophene with β-isomers has shown significantly improved air stability maintained over 270 days. This stabilization effect is ascribed to the low-lying HOMO level and the dense packing realized by perpendicular molecular arrangement.