Agilent Technologies, Inc.

Sammye Elizabeth Traudt

William H Wilson

Paul C Dryden

Richard P White

Jane Ann Leous

Robert C Henderson

Thomas D Harrison

Thomas E Price

Fanny Hauser

George P Walsh

Jonathan Michael Frentzel

Headspace sampler

In gas chromatography (GC), a sample is introduced into a flow of carrier gas and the mixture is driven through a heated GC column to acquire chromatographic data from the sample. During this time, the column is heated from an initial temperature to a final temperature. Subsequently, the column is cooled according to a cooling program. The cooling program may include a first cooling ramp, a subsequent isothermal hold, and a subsequent second cooling ramp. Alternatively, while the column is cooled down the flow of carrier gas through the column may be slowed down or ceased for a period of time, after which the flow of carrier gas through the column may be resumed at the original flow rate in preparation for processing another sample. Controlling column temperature and/or flow in this manner may be effective for reducing column bleed carryover and/or the effects thereof.

Method and system for reducing the effects of column bleed carryover

A heating apparatus for a gas chromatography column is described. The GC column heating apparatus includes a conical heater assembly comprising a heating element between an inner layer and an outer layer. The apparatus can also include optionally an outer cowl and/or an inner cowl surrounding the conical heater assembly. The conical heater assembly rapidly increases the temperature of the column by conductive heating. The selection of shape (in particular, the cone angle of a conical heater) and materials allows the GC column to adapt to expansion that occurs upon heating. A gas chromatography (GC) column heating and cooling apparatus is also described, in which the heater and outer cowl define a flowpath through which a cooling fluid can pass and cool the GC column.

Conical heater assembly for a gas chromatography column

An apparatus includes a first column heating apparatus, which includes: a first substrate; a second substrate including silicon; and a first heating element disposed between the first substrate and the second substrate. The apparatus also includes a second column heating apparatus, which includes: a third substrate; a fourth substrate including silicon; and a second heating element disposed between the third substrate and the fourth substrate.

Gas chromatography (GC) column heater

An apparatus for heating a GC column is described. The apparatus includes first and second temperature sensors. Temperature data are used to set power provided to a heating element of the apparatus.

Gas chromatography (GC) column heater control using multiple temperature sensors

A gas chromatography (GC) column heating apparatus is described. The GC column heating apparatus includes a first substrate; a heating element disposed over the first substrate; and a second substrate. A gas chromatography (GC) column heating and cooling apparatus is also described. The GC column cooling and heating apparatus includes a housing configured to receive a heating apparatus, the heating apparatus comprising a first side and a second side; a first thermal insulation layer disposed over the first side; a second thermal insulation layer disposed over the second side; and an actuator connected to the housing and configured to move the first and second thermal insulation layers in contact with the first and second sides, respectively, during a heating sequence, and to move the first and second layers of insulation out of contact with the first and second sides, respectively, during a cooling sequence.

An analytical column includes a coating that absorbs at least one of ultraviolet (UV) and visible (VIS) radiant energy and converts the radiant energy into heat.

Radiant thermal energy absorbing analytical column

An improved gas chromatograph system includes a radiant source, an insert located to receive an output of the radiant source, and an analytic column wound on a concave surface of the insert so that successive coils of the wound analytic column are in direct contact with each other and exert an outward pressure on the concave surface of the insert such that the outward pressure minimizes a gap between the analytic column and the concave surface of the insert so as to minimize thermal gradients and maximize heat transfer to the analytic column.

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Middletown, DE, United States of America

Sammye Elizabeth Traudt