The evaluation method of ultrafiltration membrane was studied using commercially available membranes with 10, 000 molecular weight cut-off. The membrane performance was checked with the aqueous solutions which contained single or mixed polyetheleneglycohol (PEG). It was found that almost the same rejections could be obtained by both feed solutions. And, it was confirmed that the molecular weight cut-off characteristics of ultrafiltration membranes could be obtained by only one measurement with the feed PEG solution containing PEG mixture using GPC liquid chromatography.

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For the purpose to standardize method to determine molecular weight (Mw) cut-off characteristics of ultrafiltration (UF) sheet membranes, firstly the efficiency of gel permeation chromatography (GPC) analysis method was investigated, secondly the effect of operating conditions of linear velocity (u) 0.15-0.60 m/s, transmembrane pressure (TMP) 10-200 kPa and feed PEG concentration (C) 500-10, 000 mg/l with five polyethylene glycol (PEG) of different average Mw 1, 000, 3, 000, 7, 500 and 20, 000 mixtured solution, using three UF sheet membranes, lastly Mw cut-off characteristics of nine UF sheet membranes were measured with five PEG mixtured solution, using GPC analysis method. Mw cut-off characteristics by GPC analysis method with PEG mixtured solution agreed well with that by TOC analysis method with single PEG solution, but slightly shift to the left compared with that by protein method. Mw cut-off characteristics did not depend on u and C, but significantly depended on TMP. The obtained Mw cut-off characteristics became smaller than that of catalog.

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Separation of gaseous mixture was carried out up to 773 k using composite microporous glass membranes coated on the surface of a porous ceramic tubings. The composition of the metal alkoxide solution used in the coating process was Si (OC₂H₅) 4 : 27.9, C₂H₅OH : 42.0, H₂O : 26.2, HCl : 0.3 and H₃BO₃ : 3.6, in weight %.
With ceramic tubings supplied from TOTO Co., Ltd., much thinner microporous glass membranes can be made because 5 times of coating was enough to get without cracks, comparing at least 7 times for TDK Co., Ltd.. The membrane can permeate only H₂O from thermochemical reaction gas mixture of H₂ and H₂O at the flux rate of 37 kg/ (m²·day) at trans-membrane pressure 0.196MPa and at 773 K.

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The present article deals with the current understandings of the characteristics of receptor sites for odorants and taste stimulants, mechanisms of discrimination of odor and taste, synergism, and the transduction of chemical information into electric signals. 1. Responses to odorants are seen not only in the olfactory system, but also in such non-olfactory systems as neuroblastoma cell and liposomes. The latter systems have no specific receptor proteins for odorants. Changes in lipid composition of liposomes lead to changes in specificity of the liposomes to odorants.
The membrane composition of each olfactory cell is postulated to be different. Different odorants will produce different response profiles in each olfactory cell, with odor quality encoded in this response profile.
2. The fact that trutle olfactory responses are independent of ion concentrations on the olfactory epithelium and the fact a large olfactory response appeared after complete elimination of carp olfactory cilia suggest that ionic permeability changes at the apical membrane of olfactory cells, including ciliary membranes, do not contribute to the ol-factory receptor potentials.
3. Sweet substances and amino acids are recognized by specific receptor proteins on taste receptor membrances, while the basic lipid-protein structure of membrane is involved with reception of salts, acids, and bitter substances.
4. Permeability of the taste receptor membrane to ions does not contribute to the taste receptor potential elicited by most stimuli. Stimulus-induced changes in phase-boundary potential leads to depolarization of the apical membrane of taste cells. Depolarization of the apical membranes activates voltage-dependent Ca channels at the synaptic area, entry of Ca ion, and release of neurotransmitter (norepinephrine).

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