Selective permeation of o-, m-, and p-isomers of benzene derivatives through polymer membranes based on cyclodextrin complexation in the bulk aqueous solution

Transport behavior of several aromatic compounds through a poly(vinyl chloride)membrane and poly(vinyl alcohol)-poly(ethylenimine) composite membranes was studied in the presence of cyclodextrin in the aqueous solution. o-Isomers of nitrophenol, nitroaniline, and iodophenol were effectively separated from their mixture of regio isomers based on the preferential complexation between cyclodextrin and the m- and p-isomers over the o-isomers. Pumping of p-nitroaniline across the membrane was also observed by addition of cyclodextrin. The results were explained as a consequence of the selective complex formation between cyclodexarin and substrate and the low membrane permeability of the complexes.     

Nonstoichiometric deep levels in Mg-doped GaP epitaxial layers: Effects of pre-annealing of substrates

The effects of substrate pre-annealing on deep level density in Mg-doped GaP liquid-phase epitaxy (LPE) layers were investigated by photocapacitance measurement. With annealing under optimum phosphorus-vapor pressure, concentration of deep donor at E_C — 1.9–2.1 eV increased in undoped GaP substrate. Deep level densities in Mg-doped layers were also affected by pre-annealing of the substrates. Densities of dominant deep levels at E_V + 0.85 eV and E_V + 1.5 eV were an order of magnitude reduced and, in contrast, the level at E_C − 2.1 eV in Mg-doped layer increased with long pre-annealing. This level at E_C − 2.1 eV is supposed to be involved with P-rich-type nonstoichiometric defects, such as phosphorus interstitial atoms diffused from the surface of the substrate.     

Stoichiometry of III–V compounds

Effects of stoichiometry control on electrical, optical and crystallographic features in III–V compounds are shown. The application of the optimum vapor pressure during annealing and crystal growth is shown to minimize the deviation from stoichiometric composition. Temperature-dependence of the optimum vapor pressure is also obtained. In view of the defect formation mechanism, existence of the stable interstitial arsenic atoms (I_As) in GaAs is emphasized. The mechanism of stoichiometry control is discussed on the basis of the equality of chemical potentials and the change of saturating solubility in the liquidus phase as a function of the vapor pressure.     

Suppression effects of active power filter on harmonics of distribution system including capacitors

Voltage distortion of 6.6-kV distribution systems has been increasing recently especially in commercial areas. Harmonic currents of certain orders are amplified and voltage distortions are generated by the resonance between system impedance and static capacitor under the leading power factor condition. This paper describes the results of a test on suppression effects on model systems and an actual system. The effect of the use of an active power filter on the resonant harmonics of the system including capacitor was verified.     

Intelligent decision support systems for nuclear power plants in Japan

This paper describes the MITI (Ministry of International Trade and Industry) projects for decision support systems for NPPs in Japan. Main attention is paid to the new project of an advanced man-machine system for nuclear power plants, of which a conceptual design was initiated in 1984. Some of the aspects of the design and the outline of the prototype system are discussed.     

Anesthesia for a patient with macrothrombocytopenia

A 56-year-old female with macrothrombocytopenia was scheduled for colectomy and hepatectomy. She had not shown significant bleeding tendency. Her preoperative platelet counts were 0.5-1.6 x 10(4) microliters-1 with the use of an automated cell counter. However, microscopic examination showed platelet number ranging 0.9-3.4 x 10(4) microliters-1 and many macrothrombocytes. Therefore, platelet biomass (platelet number x platelet volume) seemed almost normal. Bleeding time was 3 minutes and platelet function was normal. She received preoperatively high dose gamma-globulin administration and intraoperatively platelet transfusion. The operation was performed under combined epidural and general anesthesia. Intra- and post-operative course was uneventful.     

The geometrical evaluation of effective diffusion coefficient in the liquid phase for porous bodies consisting of spherical elementary particles

To evaluate the intraparticle diffusion coefficient, De, of a component in a liquid, it was assumed that the pore structure of a porous catalyst was a space between an assembly of fine particles. This structure has been found for the metal oxide catalysts. The diffusivity ratio, δ (= De/D), was geometrically estimated in the direction normal to the representative plane (100), (110) or (111) of cubic closed, body centered cubic, simple cubic, or diamond packing of spherical elementary particles. The value δ was found to approximate the porosity ?. Larger pore constrictions gave smaller δ/? values. Reaction rates were measured for the hydrogenation of nitrobenzene in ethanol. The efficiency of this evaluation of De was supported by the agreement of the experimental effectiveness factor with the theoretical factor.