Effective 4ƒ energy level in virtual excitation and in photoemission processes in Ce-pnictides

Effects of relaxation of occupied band electrons to the ?-hole state through the hybridization between ? and band states are studied based on a detailed model for Ce-monopnictides. The effective 4? level is shifted about 1–2 eV to shallow energy side from the unrenormalized bare level in processes in which the 4? electron is only virtually excited, such as in excitation to the vacant p band states through the p-? mixing. Photoemission spectra show two peaks, one near the Fermi energy and the other about 3 eV below it. The latter is shifted to deep energy side about 0.5–1 eV from the bare level when it lies near the bottom of the valence band. The discrepancy between the 4? level estimated from the low energy phenomena and that from photoemission is resolved.     

DMPM (3,4-dimethoxybenzyl) protecting group for hydroxy function more readily removable than MPM (P-methoxybenzyl) protecting group by DDQ oxidation

The DMPM (3,4-dimethoxybenzyl) protection for hydroxy function was deprotected more readily than the MPM (p-methoxybenzyl) protection by DDQ oxidation under neutral conditions, and applied to the synthesis of some synthons to macrolide and polyether antibiotics.     

Structure and synthesis of unsaturaded trihydroxy c18 fatty : Acids in rice plants suffering from rice blast disease

Structural elucidation including the absolute configuration was carried out on the trihydroxy C₁₈ -fatty acids isolated from rice plant, Sasanishiki suffered from rice blast disease.     

Sedimentation transport method for determination of molecular weight distributions

The sedimentation of the system polystyrene-cyclohexane at the Flory temperature has been studied with emphasis on the effects of pressure as well as concentration. The relation between the molecular weight M and the limiting sedimentation coefficient s₀⁰, is found to be s₀⁰ = 1.50 × 10^?15 M^1/2 (sec.) The concentration dependence parameter k_s has the form, k_s = k′M^1/2 = k″s₀⁰ with k′ = 4.5–5.5 × 10^?4. However, a rather unexpected dependence of k_s on the rotor speed is also found. A procedure is proposed for deducing solute molecular weight distributions from boundary spreading data in sedimentation transport experiments, a so-called “single concentration” method, requiring only one sedimentation run. Application to several polystyrenes (in cyclohexane at 35°C) with narrow, broad, and very broad distributions demonstrates the feasibility of the procedure. Comparisons are made with data from elution chromatography and gel permeation chromatography. The GPC method predicts somewhat broader distributions than those obtained by the other two methods.     

Quantitative determination of methyltestosterone and methyltestosterone-d3 in serum by gas chromatography-mass spectrometry

A method for the quantitative estimation of methyltestosterone and methyltestosterone-d3 in biological fluids has been developed using gas chromatography-mass spectrometry-selected-ion monitoring. Methyltestosterone-d6 was used as an internal standard. Methyltestosterone and methyltestosterone-d3 in serum were determined based on the peak height ratios of the molecular ions of methyltestosterone, methyltestosterone-d3 and methyltestosterone-d6. Sensitivity, specificity, precision, accuracy and reproducibility of the present method were demonstrated to be satisfactory for application to pharmacokinetic and bioavailability studies.     

Anomalous resistivity near curie temperature due to the critical scattering

Critical behavior of the temperature derivative of the electrical resistivity at the Curie temperature is treated in general. It is shown by treating the sum rule in the correlation function rigorously that, for a large Fermi wave vector, the divergence is similar to that of specific heat both below and above the Curie temperature, but for a small Fermi wave vector, the de Gennes—Friedel region appears at higher temperatures. Comparison with other divergent mechanisms are also done.     

Stability condition for molecular magnetic polaron

It is shown that under suitable conditions a short range attractive interaction is expected for two magnetic polarons which causes formation of molecular magnetic polaron. For many valley band structures, the attractive molecular magnetic polaron. For many valley band structures, the attractive potential is enhanced and several electrons may form a giant magnetic polaron. Application for bubble domain is also proposed.