Hewlett-packard Company

Rosemount Inc.

Beckman Industrial Corporation

James H Crabtree

Fred Charles Sittler

Carl A Farren

Philip Leigh Wylie

Kenneth R Weiner

Screening an unknown sample for a plurality of known or 'target' analytes may be accomplished by creating and searching a retention time-locked spectral database for the entire chromatographic output of a locked GC system locked to such spectral database. Identification of target analytes having for example, known significant mass spectral ions and mass ion ratios corresponding to known analytes of interest believed to be found within a pre-defined retention time window is improved by direct comparison of significant mass spectral ions and the mass ion ratios within a specified retention time window.

Retention time-locked spectral database for target analyte analysis

A thermal effect sensing device comprises a semiconductor substrate supporting an insulating layer which has a thin film of platinum deposited on it. Holes are etched through the semiconductor substrate and the insulating layer. The platinum film is shaped to provide a serpentine resistive element suspended over one of the holes. The serpentine element is suspended from the rim of the hole, but is otherwise unsupported. The resistive element has a low thermal mass and there is a low thermal resistance between the element and fluid in the sensor. The sensor senses thermal properties of the fluid in the sensor, such as mass flow or thermal conductivity. A second conductive film is insulatingly deposited on the first film to provide a resistive sensor electrically isolated from a resistive heating element.

Fluid flow detector

The present invention relates to a gas chromatography assembly comprising a high mass, thermally conductive body provided with at least one cell in which is disposed a resistance filament for the detection of a sample gas. Lines are provided for communication between the cell and sample gas and carrier gas from chromatographic separation columns. The conductive body is adapted to carry the separation columns in heat transfer relationship therewith. In accordance with the present invention, the assembly components, including the interior of the cell and the separation columns are heated with a single heating element, which is controlled by a single heating element control means. The temperature of the environment of the sensor, switching valves and the separation columns, are thus controlled through a single constant temperature control system. Each element of the assembly is provided with sufficient surface area at the point where it is joined with an adjacent element of the assembly to define a flame path of sufficient length to prevent the escape of a flame from between the contiguous elements.

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Long Beach, CA, United States of America

James H Crabtree