Basic nature of nuclear track membranes for liquid media

• Published in: New astronomy reviews Vol. 42; no. 3; pp. 205 - 216
• Main Author: Guo, Shi-Lun
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.09.1998
• Subjects: Bacteria filtration; Blocking formula; Chemical separation; Liquid media; Liquid mixture separation; Nuclear track membranes; Solution concentration determination; Viscosity determination; Blocking formula; Liquid media; Liquid mixture separation; Nuclear track membranes; Chemical separation; Solution concentration determination; Bacteria filtration; Viscosity determination
• ISSN: 1387-6473; 1872-9630
• DOI: 10.1016/S1387-6473(98)00005-0

Nuclear track membranes (NTM), because of their straight pore structures and unitary pore size, will become indispensable materials in future science and technology. After steady development since the 1960's, nuclear track membranes have been widely used in various fields. Extensive detail of their nature and properties are now recognized. A review is given of the nature and properties of nuclear track membranes in the case of liquid media passing through the membranes. The following subjects are included here: (1) For pure liquid media the applicability and limitation of Poiseuille's formula to the calculation of flow rates have been discussed. Several techniques for the determination of liquid viscosity with NTM's have been developed and successfully tested and classified, either as absolute or relative; the latter is further sub-classified either as an absolute or kinematic viscosity determination. (2) For liquid solutions a method for solute concentration determination with NTM's has been conceived and tested. These tests show that NTM's are unique and simple devices when applied to the determination of chemical concentrations of many substances in various solvents. (3) For liquid mixtures, such as oil in water, separation of different phases of liquids can be accelerated by using NTM's. This technique can be used in the purification of liquids. The principle and application of liquid phase separation to chemical separations are also explored. (4) Blocking phenomenon of NTM's by liquids containing microscopic solid particles have been studied and a blocking formula to calculate the flow rate of liquids containing solid particles is derived. By fitting the formula to measured data of flow rates we can estimate the number, size and shape of the solid particulates suspended in a unit volume of the liquid. Finally (5), for liquids containing bacteria, filtration of bacteria with NTM's has been studied in detail. Some basic rules and key factors are suggested for the removal of bacteria from liquids. Details in the latest developments of the above subjects are summarized.