Spin physics in the high energy hadron productions. A systematic study of the spin asymmetries induced by <Emphasis Type="Italic">pp, γp,ep</Emphasis> and λ<Emphasis Type="Italic">p</Emphasis> collisions

The spin polarizations of hadrons inclusively produced by pp, γp and λp collisions are studied by the quark rearrangement model. The present model is a phenomenological one based on the relativistic spin equations of motion and using the quark distribution functions in hadrons and photon. A general success of the model is demonstrated. We find usefulness of the present formulation for studying the dynamics producing spin asymmetry distributions and the statics determining signs and magnitudes of the spin polarization by reflecting the characteristic quark structure in hadrons.     

Quasi-solid-state dye-sensitized solar cells using room temperature molten salts and a low molecular weight gelator

A dye-sensitized solar cell fabricated using the room temperature molten salt, 1-hexyl-3-methylimidazolium iodide, iodine and a low molecular weight gelator as a quasisolid-state electrolyte showed a 5.0% light-to-electricity conversion efficiency under AM 1.5 irradiation, and high-temperature stability.     

Extremely low vertical-emittance beam in the accelerator test facility at KEK

Electron beams with the lowest, normalized transverse emittance recorded so far were produced and confirmed in single-bunch-mode operation of the Accelerator Test Facility at KEK. We established a tuning method of the damping ring which achieves a small vertical dispersion and small x-y orbit coupling. The vertical emittance was less than 1% of the horizontal emittance. At the zero-intensity limit, the vertical normalized emittance was less than 2.8 x 10(-8) rad m at beam energy 1.3 GeV. At high intensity, strong effects of intrabeam scattering were observed, which had been expected in view of the extremely high particle density due to the small transverse emittance.     

A practical synthesis of the ABC ring model of ecteinascidins

A practical synthesis of 1,2,3,4,5,6-hexahydro-1,5-imino-10-hydroxy-9-methoxy-3,8,11-trimethyl-3- benzazocin-4-one (3) as an ABC ring model compound of ecteinascidin 743 and safracins from 3-hydroxy-4-methoxy-5-methylbenzaldehyde (7) is described. The overall yield in 15 steps is 27%.     

Synthesis, complexation, and fluorescence behavior of armed crown ethers carrying naphthyl group

Armed crown ethers (1-4) bonding through an amine, amide, ether, or ester linkage to naphthyl group were found to display unique photophysical properties in the presence of guest salts. Complexation of PET fluoroionophores (1a and 1b) with Zn(2+) increased the fluorescence intensities of the host by a factor of 2.4 and 2.7, respectively. (1)H and (13)C NMR analyses of this complexation behavior of 1a revealed that Zn(2+) strongly coordinates with the armed crown nitrogen to cause a dramatic decrease in an intramolecular charge-transfer character. The armed crowns (2 and 3), bonding through an ether or ester linkage to a naphthalene, gave fluorescence quenching with guest thiocyanates. While the amide derivative (4) exhibited high Ba(2+) fluorescence selectivity and in the presence of this cation the host fluorescence intensity was by a factor of 3.69.     

Further evidence for the intramolecular charge-transfer interaction between tropylium ion and remote benzene rings in 9,10-dihydro-9,10-(1,2-tropylio)anthracene tetrafluoroborate and its methyl derivatives

A series of 9,10-dihydro-9,10-(1,2-tropylio)anthracene tetrafluoroborates

has been prepared. The intramolecular charge-transfer interactions in

were confirmed by their UV spectra and pK_R+ values. As a model compound 1,2,3,4-tetrahydro-1,4-(1,2-tropylio)naphthalene tetrafluoroborate ($\text{5}$)_was also examined.     

Concentration wave description of an early stage kinetics of clustering and ordering in ordered phase

Kinetic theory of early stages of coherent clustering and continuous ordering in ordered phase is developed using the concept of concentration waves on the assumption of mean field energy. Linear differential equations of atom diffusion in ordered phase are solved by diagonalizing the coefficient matrix of the equations. It is shown that at the early stages of the reaction the concentration (fluctuation) waves evolve exponentially with respect to time on the sublattices of the ordered phase.The theory is applied to the Fe-10.9 at. %Si alloy which exhibits a sequence of transitions on aging at 775K. It is proved that the first transition from the disordered to the B2 phase occurs purely due to the kinetic reason that the amplification factors of the fluctuation waves have a positive maximum value only at the superlattice point of the B2 structure in the first Brillouin zone of the disordered phase. The second transition, which is from the metastable B2 phase to the stable phase, i.e. the spinodally decomposed D03 phase, is also explained consistently by the present theory that the amplifications calculated in the B2 phase exhibit two positive maxima in the first Brillouin zone. The maximum at point $\text{(q) = (}\text{1}\text{2}\text{1}\text{2}\text{1}\text{2}\text{)}$ represents the amplification factor of the D03 ordering-wave in the B2 phase, while the other close to the Brillouin zone center represents the amplification factor of the fluctuation wave of the spinodal decomposition.     

Selective and efficient transformation of N-(4-substituted benzoyl)-α-dehydroarylalanine alkyl esters into 4,5-dihydrooxazole derivatives via photoinduced electron transfer

The irradiation of N-(4-substituted benzoyl)-α-dehydroarylalanine alkyl esters (1) in methanol containing triethylamine (TEA) was found to quantitatively give cis- and trans-4,5-dihydrooxazole derivatives (2), which were described as being formed via electron transfer from TEA to the excited-state (E)-1 followed by kinetically-controlled cyclization of the (E)-1-derived anion radical. A product composition analysis showed that the cis-2/trans-2 composition ratio is greatly varied depending on the stereoelectronic properties of the substituents, the polarity of protic solvents and the concentration of TEA.     

Impulse response techniques to measure binary diffusion coefficients under supercritical conditions

This review describes impulse response techniques with a curve-fitting method to measure thermodynamic properties, such as binary diffusion coefficient, retention factor, and partial molar volume, under supercritical conditions. Theoretical background, parameter sensitivity, sources of experimental error, noise elimination technique, and the correction of apparent binary diffusion coefficients due to column coiling are discussed based on recent studies, together with data sources and predictive correlations for binary diffusion coefficients.