Synchrotron X-ray scattering experiments make it possible to investigate dynamic structural changes in biological materials. This extremely high intense X-ray source is applied to the study of hydrated phospholipid multilamellar vesicles which undergo phase transitions. Time-resolved X-ray scattering experiments after temperature jump make clear the kinetics of the phase transitions. Real time X-ray scattering experiments at low temperature scan rates are the powerful methods for observing transient structural changes during the phase transitions.

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Ceramic micro- and ultrafiltration membranes suitable for use in bioprocesses can now be made from a wide range of inorganic materials. This article describes the membrane properties attributable to manufacturing procedure. The studies concerning the filtration of bacterial cells by ceramic membranes are also reviewed. Since ceramic membranes have a potential to vary the properties such as pore size, membrane resistance, zeta potential and surface free energy, the examinations to clarify the relationship between membrane properties and filtration characteristics were carried out. And concept for the designing of membranes using filtration of methanogenic cells was proposed. To apply the ceramic membranes for bioprocesses widely, the investigations to establish the concept for the optimum designing of membranes, and also to estimate the influence of shear induced by filtration operations on lysis of cells will be needed.

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Inorganic membranes, which have excellent stability compared with organic ones, have been reviewed from the standpoint of application to non-aqueous solution system. In the first part, inorganic membranes are classified on the basis of preparation procedure and structure, and permeation mechanism through the membrane is reviewed Based on the theoretical discussion species in the non-aqueous mixture are separated by :
1) molecular sieve→innovation of molecular sieve membrane
2) solution diffusion→development of organic-inorganic composite membrane
3) surface or condensed flow
In the second part, research topics reported so far are described in details. Possibility of inorganic membranes in non-aqueous mixture separation is demonstrated.

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For the purpose to find out the issues on standardizing method of determining molecular weight cut-off characteristics of single hollow fiber ultrafiltration (UF) membrane, retention of four polyethylene glycol (PEG) of different average molecular weight 3, 000, 7, 500, 20, 000 and 50, 000 was measured under the following conditions of transmembrane pressure (TMP) 10, 20, 30kPa and linear velocity (u) 0.02-0.32m/s, using UF membrane PM-10 supplied from Amicon. The dimensions of hollow fiber used are the followings; inner diameter is in the range of 0.8mm to 1.15mm, and effective length 30cm.
The measured retention (Robs) increases with the increase of u and decreases with the increase of TMP. Mass transfer coefficient (kobs) of PEG on the surface of hollow fiber UF membrane is obtained from the relationship between Robs and u, and compared with the theoretically derived k by Léveque and that by boundary layer theory. The agreement between kobs and Léveque's k is good. Using Léveque's k, Robs is corrected by removing the concentration polarization effect to obtain intrinsic retention (R). The obtained R dose not depend on u but slightly depends on TMP. The reliability of R increases with the decrease of TMP.

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Novel synthetic polymeric membranes from cellulose acetate and 2, 7-thianthrene dicarboxylic acid-5, 5', 10, 10'-tetraoxide showed permselectivity toward SO₂ against O₂ and N₂. It was made clear that an incorporated carrier, 2, 7-thianthrene dicarboxylic acid-5, 5', 10, 10'-tetraoxide, played an important roll for selective permeation of SO₂ through the membrane.

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Separation of gaseous mixture was carried out in the temperature range from 298 to 773 K using a composite microporous alumina membrane, thin alumina membrane have been prepared on the surface of a porous ceramic tubing by coating wet sol-gel method.
Structure of the membranes was investigated by Scanning Electron Microscope, and the best composition of the metal alkoxide solution used in the coating process was Al (OC₃H₇) 3 : 1, H₂O : 100, i-C₃H₇OH : 0.67 and HCl : 0.07, in molar ratio.
The membrane allows to permeate only H₂O from thermochemical reaction gas mixture of H₂ and H₂O at the flux rate of 69kg/ (m²·day) at trans-membrane pressure 98kPa and at 773 K.
Taking into account the change of viscosity in the flow direction, the observed data were analysed by the permeation equations proposed by Present and de Bethune, and the calculated results were in good agreement with the observed data.

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For the purpose of gas separation at high temperature, a thin porous silica membrane of ultra fine pores has been prepared by the sol-gel method, where silica sol was coated near the outer surface of a porous cylindrical substrate of α-alumina, then it was dried and fired at around 450°C.
Permeability measurements for H₂, He and N₂ through the silica membrane were carried out at various temperatures (30-270°C) to show that the permeabilities of H₂ and He, which increased with the increase of temperature, were 30-300 times larger than that of N₂, and that the permeability of He was appreciably larger than that of H₂, These results clearly show that the activated diffusion or permeation prevails instead of the Knudsen diffusion through the silica membrane, while the permeability of N2 showed a negative temperature dependency, which is probably due to the Knudsen diffusion through some pin holes still left in the membrane. The activation energy for HZ and He were estimated to be 8.3kJ/mol and 4.0kJ/mol respectively.
Separation results for H₂/N₂ and He/N₂ mixtures at 270°C showed that large separation ratio could be obtained, and also that each gas component permeated independently without any molecular interactions among permeating molecules in the fine pores of the silica membrane, Which makes possible an estimation of separation performance from the permeation results for pure gases.

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A DOPH-Millipore membrane shows electric self-sustained oscillations with periods of a few seconds under salt-concentration gradient, electric current and pressure difference. We have found that the oscillations with periods of a few seconds are induced by the addition of acid without the electric current and the pressure difference.

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