The Dow Chemical Company

Dow Global Technolgoies LLC

Nile Nelson Frawley

Lawrence W Nicholson

Timothy S Stevens

Mark William Beach

Curtis D Pfeiffer

Philip J Savickas

William Charles Harris

Daniel J Swart

Thomas L Peters

Jeffrey Robert Larson

Steven J Gluck

Steven Randall Erskine

Steven R Erskine

Deborah E Diedering

L David Rothman

Mark Lindsay Dittenhafer

Jose B Esquivel H

Joseph J Kiefer

David R Albers

A method for calibrating an analysis instrument, e.g., a gas chromatograph, for water analysis that includes four steps. The first step is to continuously remove water from a liquid that contains water to produce a liquid containing a reduced amount of water such as by membrane pervaporation. The second step is to analyze the liquid containing a reduced amount of water for water by a reference water analysis method such as by Karl Fischer titration. The third step is to analyze the stream of liquid containing a reduced amount of water using the instrument to be calibrated, e.g., a gas chromatograph having a helium photoionization pulse discharge detector. The fourth step is to calibrate the instrument using the analysis of the second step. In a related embodiment, a system for normal phase chromatography.

Method and apparatus for determination of water and for normal phase liquid chromatography

A chemical analysis method for determining chemically related differences between subject biological material such as genetically modified plant material and control biological material such as genetically unmodified plant material, which method includes at least the following six steps. The first step is to contact the subject biological material with a fluid extractant, such as a mixture of water, isopropanol and potassium hydroxide, to produce a fluid extract of the subject biological material. The second step is to contact the control biological material with the fluid extractant to produce a fluid extract of the control biological material. The third step is to chromatograph the fluid extract of the subject biological material, for example, gas or fluid chromatography, to produce a chromatogram of the fluid extract of the subject biological material. The fourth step is to chromatograph the fluid extract of the control biological material to produce a chromatogram of the fluid extract of the control biological material. The fifth step is to determine the differences between the chromatograms, for example, by using the method of U.S. Pat. No. 5,592,402, to identify at least one outlier peak. The sixth step is to determine the chemical identity of the outlier peak, for example, using gas chromatography/mass spectroscopy analysis of the outlier peak.

Method for chemical analysis of biological material

This invention relates to the preparation of, and a device for using, a permanently deformed sulfonated halopolymer article. A flexible and non-brittle flange may be formed from at least one end of a hollow perfluorosulfonic acid membrane in one aspect of the invention. The flanged membrane is particularly useful for quick attachment and detachment to various instrumentation used for pervaporation. In addition, by packing the membrane with a means for increasing radial diffusion of fluid within the membrane, pervaporation efficiency may be increased.

Permanent deformation and use of sulfonated halopolymer articles

An analytical chemistry apparatus and method for introducing a reagent into a flowing stream of liquid carrier in order to quantitatively analyze one or more components of a sample added into the carrier. The reagent is permeated across a short section of membrane having relatively large pores. The use of such a membrane: (a) allows the membrane to be protected from physical damage by covering it with a perforate structure; (b) significantly reduces bandspreading across the membrane reagent addition device; (c) reduces the pressure drop across the membrane reagent addition device; and (d) still allows for the permeation of an effective amount of the reagent into the carrier. The reagent is preferably pressurized to minimize leakage of carrier across the membrane and the reagent can be self-pressurized by essentially completely filling the reagent reservoir of the invention with reagent and then hermetically sealing the reservoir.

Method for reagent addition to a flowing liquid carrier stream

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Midland, MI, United States of America

Nile Nelson Frawley