Since January 1981 American Society for Testing and Materials (ASTM) has worked to set up the Semiconductor Grade Water Specifications, in which it is proposed that living micro-organisms should be less than 1 colony per 100 ml.
This proposed specification is much tighter compare with current numbers in Japan, less than 50 colonies per 100 ml. It may be possible to achieve the specification from the fact that the specification has been performed in Pharmaceutical industry, however it would be very difficult to achieve the specification in Semiconductor industry due to the difference of purpose and volume to use high purity water in both industries, especially it is most difficult in the plant operated intermittently such as laboratories.
Recent advanced Ultrafiltration (UF) unit could be useful to solve the difficulty. The unit is installed at the final position of total system for this concept, practically UF element must be selected from many brands in the market according to specifications required. It is also a definite opinion in Semiconductor industry that recent UF unit is better than RO unit as long as they are used in final position of the system.

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The phase change between expanded and condensed states was investigated in monomolecular films of lipid mixtures on water. Various kinds of lipids were used and surface pressure-area isotherms for mixed monolayers with different compositions were measured precisely at various temperatures. The thermodynamic treatment of the isotherms made us construct two-dimensional phase diagrams. It was found that there exist ideal system, incomplete mixed system, positive azeotropic system, negative azeotropic system and eutectic system in mixed monolayers depending on the molecular structure of lipids.

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Transport system of rat and bovine erythrocyte membranes was studied comparatively by the observation of the inhibitory effects of benzenesulfonic acid derivatives on the transport of oxalate through both membranes. Although the permeability of rat erythrocyte membrane was larger than that of bovine erythrocyte membrane, the inhibitory effects of benzenesulfonic acid derivatives in both membranes resembled with each other. It was shown that the electronic property has a significant effect, but the hydrophobic property has less effect : the inhibitory effects are mainly dependent on the electron acceptor capacities. The position of the substituents was also revealed to be important for the inhibition. Moreover, in rat erythrocy te membrane, the order of the inhibitory effects of benzenesulfonic acid derivatives is almost completely reverse to that of transport rates. This strongly clarifies that the transport is regulated by the binding capacities of anions to the transport site.
In this study the usefulness of ammonium salt lysis method to measure the inhibitory effects was also revealed.

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