Recent advance of polymeric membranes for gas separation was reviewed. The polymeric membranes were classified as follows : membranes for (1) oxygen/nitrogen separation, (2) hydrogen separation, (3) carbon dioxide separation, and (4) other gas separation. In the field of oxygen/nitrogen separation, new polymeric membranes containing trimethylsilyl group showed the highest gas permeability. In the field of hydrogen separation, a new polyimide membrane containing cyclic hydrocarbon rings in the main chain showed both high permeabilities and separation factors. In membranes which have permselectivity for carbon dioxide, sulfoxide-modified poly (vinyl alcohol) membranes are very attractive. The speciality polymeric membranes containing carriers in which a facilitated transport took place were also introduced.

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National Chemical Laboratory for Industry, 1-1 Higashi, Tsukuba-shi 305, Japan Poly-L-glutamic acid accelerated by about 25% the cyclic photophosphorylation in the thylakoid a thermophilic cyanobacterium. A mixture of poly-L-glutamic acid and poly-L ornithine of a ratio 2/1 (w/w) also enhanced by 20-30% the photophosphorylation. The acceleration behaviors by poly-L-glutamic acid alone are different from those by the mixture of acidic and basic poly (amino acid) s.

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The surface structure of an artificial membrane composed of a Millipore filter and a synthetic lipid analogue, dioleylphosphate (DOPH), immersed in KCl solution changes from a highly reflective hydrophilic state to a poorly reflective hydrophobic state by increase of calcium ion concentration in KCl solution. Using a microscopic digital image processing system the structural changes can be estimated quantitatively, such as a histogram of the brightness level and a binary black-and-white picture. The gross area of hydrophilic domains and the mean diameter of hydrophilic particles were measured by processing a binary picture

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We intended to show the applicability of the regenerated cellulose hollow fiber (BMM) to the preparation of plasma products free from hepatitis B virus (HBV). In order to evaluate the HBV removability of BMM and to exclude the contribution of the heterogeneities of the hollow fibers which will affect the ability of BMM, two types of module (i.e. a S-module with its effective filtration area of 0.6 cm² and a M-module with 300 cm² or 500 cm²) were employed. The purified HBV particle were prepared from HBV positive plasma by rate zonal centrifugation method. The concentration of HBV particles in the samples were assayed by the spot hybridization method for HBV-DNA.
The virus logarithmic rejection coefficient Φ for HBV was approximately expressed by the following empirical and reduced equations, Φ₁ (exp) =7/ (2rf-15) for free HBV-DNA (empirical) Φ₂=96/ (2rf-30) for HBV particles (reduced) where 2 rf was the mean pore diameter in nm unit obtained through the water filtration rate method.
When HBV positive human plasma was filtered by M-module, the observed Φ value of HBV-DNA was always between Φ₁ and Φ₂, because of the free HBV-DNA in plasma and heterogeneities of the hollow fibers. The filtration rate was proportional to (2rf) ^2/and was more than 3 l/m²· hr at the transmembrane pressure of 200 mmHg and the sieving coefficient of the total plasma protein was more than 90% when 2rf was larger than 30 nm.

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