초록 ▼

A filter comprises a nonporous support member open at one end and a porous disc rigidly secured to the support member at an opposite, preferably smaller, end. The disc may be formed from fibers preferably having a thickness of approximately 0.5-50 micrometers, or it may be formed from a plurality of

A filter comprises a nonporous support member open at one end and a porous disc rigidly secured to the support member at an opposite, preferably smaller, end. The disc may be formed from fibers preferably having a thickness of approximately 0.5-50 micrometers, or it may be formed from a plurality of particles or beads retained by a pair of membranes. When the disc is relatively small such as approximately 1 millimeter in diameter, it may be pressed into a constricted end of the support member. When the disc has an increased diameter, it may be rigidly supported by a retainer preferably made from a mesh material and welded to the support member. For even larger disc sizes, the disc may be supported between two (2) retainers preferably welded to the support member. A plurality of receptacles may be disposed in a tray to, serve as the filters, or receive the filters. The fluid may be introduced into, and retained in, the support members and discs by capillary action. The fluid may be passed through the filters by centrifuging the tray with the filters. The trays bearing the filters may be centered in a container to inhibit contact with the container walls and fluid vapor may be passed through the container to interact with material on the centered filters. An absorbent sheet moistened with the fluid may be positioned against the container walls to maximize vapor content within the container.

대표청구항 ▼

Apparatus for receiving a substance and for changing the characteristics of the substance comprising: means enabling substantially complete comingling of minute volumes of reactants for chemical reaction and substantially complete recovery of the reaction products therefrom, including a hollow conic

Apparatus for receiving a substance and for changing the characteristics of the substance comprising: means enabling substantially complete comingling of minute volumes of reactants for chemical reaction and substantially complete recovery of the reaction products therefrom, including a hollow conical support member made of fluid-tight plastic material and having a large end and a smaller end, the large end being open, the smaller end having a front edge; and a disc of hard, fibrous material being plugged from the larger end into the smaller end of the support member, said disc being seated under radial compression inside the support member substantially flush with the front edge of the smaller end of the support member, the hard fibrous material of the disc cooperating with the plastic material of the support member to retain the disc in fixed relationship to the support member so as to withstand centrifugal forces when being centrifuged.