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Dive into the research topics where Dean Larry Duval is active.

Publication


Featured researches published by Dean Larry Duval.


Journal of Analytical and Applied Pyrolysis | 1998

Quick identification of polymeric dye transfer inhibitors in laundry detergents by pyrolysis-gas chromatography/mass spectrometry

Toshihiko Uchiyama; Akihiko Kawauchi; Dean Larry Duval

Abstract This report summarizes method development for the simultaneous identification of dye transfer inhibitors (DTIs) using pyrolysis-gas chromatography with mass detection (Py-GC/MS). Ground detergent products are directly pyrolyzed and pyrolysis fragments introduced into a GC column. Key fragments separated via GC are detected by selected ion monitoring (SIM) to achieve the high sensitivity and selectivity necessary to measure markers of DTIs in the presence of high levels of surfactant by products. Trace levels of DTIs, poly- N -vinylpyrrolidone (PVP), copolymer of N -vinylpyrrolidone and N -vinylimidazole (PVPVI), and poly-4-vinylpyridine- N -oxide (PVNO) in laundry detergent products were quickly identified. Detection limits were 0.05% for PVP and 0.1% for PVPVI and PVNO.


Journal of the American Oil Chemists' Society | 1996

Identification and quantitation of surfactants in consumer products by ion-spray mass spectrometry

I. Ogura; Dean Larry Duval; Shoji Kawakami; Koichiro Miyajima

Current approaches for identifying and quantitating surfactants in various product matrices require the use of wet chemical, chromatographic, and spectroscopic techniques. The primary objective of this work is to replace current multiple-technique approaches for identifying surfactants and quantitating their homologue distribution with a single rapid technique. To meet this objective, a simple preparation procedure has been developed to prepare consumer product samples for subsequent analysis by ion-spray mass spectrometry. Quantitation of linear alkylbenzene sulfonates in detergents with this technique is demonstrated.


Journal of the American Oil Chemists' Society | 1995

Characterization of brighteners in detergents by high-performance liquid chromatography/mass spectrometry/ultraviolet/fluorescence and three-dimensional high-performance liquid chromatography

I. Ogura; Dean Larry Duval; Koichiro Miyajima

A method has been developed for the identification of unknown brighteners in detergents by a high-performance liquid chromatography (HPLC)/mass spectrometry (MS)/ultraviolet (UV)/fluorescence system with MS/MS capability. Ten brighteners from five groups—stilbene, biphenyl stilbene, pyrazoline, oxazole, and coumarin derivatives—were separated on a C8 reverse-phase HPLC column. The UV and fluorescence detectors positively located the brightener peaks and differentiated betweentrans andcis isomers separated by the chromatographic system. Ion-spray (IS)/MS and IS/MS/MS spectra were then used to identify the structure of unknown brighteners in detergent products. An HPLC with a diode-array detector provided a quick identification check and accurate quantitative data for known brighteners, even on overlapping peaks.


Archive | 2003

Fabric article treating method and apparatus

Christian Gerhard Friedrich Gerlach; Bradford Scott Barron; Dean Larry Duval; Eugene Joseph Pancheri; Mary Jane Combs; Paul Eugene Rienzo


Archive | 2001

Stable, aqueous compositions for treating surfaces, especially fabrics

Hirotaka Uchiyama; Janese Christine O'brien Stickney; Jonathan Robert Cetti; Ricky Ah-Man Woo; Dean Larry Duval; Gayle Marie Frankenbach


Archive | 2004

Fabric article treating system and method

Shulin Larry Zhang; Trace Wendell De Guzman Trajano; Kofi Ofosu-Asante; Joseph Dean Heatherly; Freddy Arthur Barnabas; Jamie Marie Childers; Cynthia Maria Bedell; Dean Larry Duval; Joia Kirin Spooner-Wyman


Archive | 2003

Fabric article treating apparatus with safety device and controller

Bradford Scott Barron; Mary Jane Combs; Dean Larry Duval; Keith David Fanta; Christian Gerhard Friedrich Gerlach; Laura Lynn Heilman; Eugene Joseph Pancheri; Paul Joseph Russo; Christopher Lawrence Smith; Pedro Vincent Vandecappelle


Archive | 2000

Methods, compositions, and articles for odor control

Ricky Ah-Man Woo; Dean Larry Duval; Daniel Scott Cobb; Robert William Kiblinger; Hirotaka Uchiyama; Toan Trinh


Archive | 2003

Method of deodorizing and/or cleaning carpet using a composition comprising odor control agent

Ricky Ah-Man Woo; Dean Larry Duval; Kristin Marie Nichols; Steven Reece; Robert William Kiblinger; Daniel Scott Cobb; Hirotaka Uchiyama


Archive | 2001

Compositions comprising cyclodextrin

Hirotaka Uchiyama; Ricky Ah-Man Woo; Dean Larry Duval; Steven Reece

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