Measuring and testing – With fluid pressure – Porosity or permeability
Patent
1998-05-15
1999-10-26
Williams, Hezron
Measuring and testing
With fluid pressure
Porosity or permeability
21032175, G01N 1508, B07B 150
Patent
active
059707828
ABSTRACT:
Particles such as bacteria may be enumerated from a liquid in an accurate and efficient manner through use of an apparatus including a filter sheet which is oriented transverse to the surface of the liquid being filtered. The filter sheet is so arranged so that, as the liquid is filtered, an increasing portion of the filter is above the surface of the liquid. As a result of the surface of the liquid dropping across the filter, a smaller fraction of the total volume of the liquid passes through the upper portion of the filter than through the lower portion of the filter. Since the number of bacteria trapped per unit area of the filter depends on the volume filtered through the area, a monotonically increasing gradient of density of filtered bacteria occurs from the top to the bottom of the filter.
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Hartley James L.
Landers Terry A.
Life Technologies Inc.
Politzer Jay L.
Williams Hezron
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