A particulate filter particularly suited for analytical gravimetric weighing applications is disclosed. The particulate filter includes a polytetrafluoroethylene (PTFE) media supported by a ring and yields stable microgram and submicrogram weighing results. The support ring may be PTFE, metal foil, or another non-hygroscopic polymer such that the mass of the filter does not vary with changes in atmospheric moisture. The filter simplifies the discharge of electrostatic charge buildup such that when a conductive filter media is combined with a conductive ring device, the discharge may be accomplished by placing the filter on a grounded weighing pan or other surface. The particulate filter can simplify filter identification by including identification symbols imprinted on each side of the filter media. Due to the chemically inert qualities of its components, the particulate filter is particularly suited for extraction techniques used during the detection of polycyclic hydrocarbons as is conducted in emissions and ambient air testing.
申请公布号
WO2005079431(A3)
申请公布日期
2007.04.12
申请号
WO2005US04962
申请日期
2005.02.16
申请人
MEASUREMENT TECHNOLOGY LABORATORIES CORPORATION;DONALDSON COMPANY, INC.;DIKKEN, DAVID, A.;NELSON, ROBERT, O.