University of North Florida
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Stuart Chalk, Ph.D.
Department of Chemistry
University of North Florida
Phone: 1-904-620-1938
Fax: 1-904-620-3535
Email: schalk@unf.edu
Website: @unf

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Chemische Technik

  • Publisher:
  • FAD Code: CTEK
  • CODEN: CHTEAA
  • ISSN: 0045-6519
  • Abbreviation: Chem. Tech.
  • DOI Prefix: NA
  • Other Name(s): Chemical Engineering
  • Language: German
  • Comments: Coming to Wiley

Citations 6

"Multivariate Sensor System For The Automatic Control Of Wastewater Streams"
Chem. Tech. 1994 Volume 46, Issue 1 Pages 77-86
Adler, B.;Brueckner, G.;Winterstein, M.

Abstract: Principles and operation of a sensor array for common water and wastewater analysis is described, together with fuzzy control of its operation such as pattern recognition for particular conditions of the water composition and the recognition of changes in the sensor performance. Field experiments were performed by a sensor array for conductivity, pH, and turbidity and a memory-programmable control for data acquisition. Stages of hard clustering by a main-component analysis (Henrion et al., 1986) and fuzzy clustering or alternatively, a neuronal network were used for data evaluation. The results indicated the successful recognition of 1% and 0.05% deviations of nonionic and anionic tensides, respectively. (SFS)
Conductivity pH Turbidity Waste Environmental Electrochemical analysis Sensor Statistics Surfactant

"The Multiple System CHROMES/CHROMAS For Detection In HPLC And Flow Injection Analysis"
Chem. Tech. 1990 Volume 42, Issue 11 Pages 484-486
Mennig, F.;Haessner, R.;Moros, R.;Mattusch, J.;Werner, G.

Abstract: The cited system (Ingenieurbetrieb fuer die Anwendung der Mikroelektronik, Erfurt) is intended for the collection and evaluation of the output from several recording instruments, for which it has eight analogue input and output channels linked to a microprocessor. For application to HPLC, the analogue signals from several selective detectors operating in series are digitized and delivered to a computer. The acquisition and storage of the data up to this point are controlled by the program CHROMES, written in Turbo-Pascal. For the subsequent calculation of the area of each Gaussian peak, readings at 40 data points are required. The stored data are evaluated off-line by the program CHROMAS; this can reproduce the output graphically on a screen and smooth the output by the running-mean or least-squares method. First and second derivatives of the recorded curves are used for peak recognition.
HPLC Column Detector Selectivity Computer

"High-speed Flow Injection Determinations Of Oxidative Agents In Aqueous-solutions Based On Reaction With An Online Generated Leuco Dye"
Chem. Tech. 1990 Volume 42, Issue 7 Pages 304-307
MUÊLLER H. ; HANSEN E. H.

Abstract: In a FIAstar 5020 automatic analyzer. (Tecator) with motor-driven injector loop (60 µL), streams (2 mL min-1) of aqueous thionine violet solution (0.2 mg mL-1) and of EDTA solution (3 g in 100 mL of water, diluted to 200 mL with acetate buffer of pH 4.7) were combined and passed through a glass reaction coil (1 m x 2 mm) under a 250-W high-pressure Hg lamp to reduce the dyestuff to its leuco form. Sample solution [e.g., Cr2O72-, Fe(CN)63-, VO3-, S2O82- or Fe3+] was injected into the stream, and the absorbance was measured at 600 nm in a Corning 252 flow-through photometer with a Hellma 178.012 QS flow-through cell (10 mm; 18 µL). Up to 180 samples h-1 can be analyzed. The limit of detection is ~1 µM. As H2O2 reacts only at concentration. of >10 to 100 mM, the determination of, e.g., 10 µM-S2O82- is possible in a 150-fold excess of H2O2.
Dichromate Ferricyanide Vanadate Persulfate Iron(III) Spectrophotometry Automation Tecator Injector EDTA Buffer pH Detection limit

"Flow Models In Flow-through Enthalpimetry With A Small Tube Cross Section"
Chem. Tech. 1988 Volume 40, Issue 7 Pages 305-306
Berge, H.;Lammert, R.

Abstract: The practical use of single-line construction, hydrodynamic injection, and displacing dosage are demonstrated and advantages and disadvantages of different constructions are discussed. The combination of flow-through enthalpimeter with flow-injection anal. technique enabled attaining high throughput rates for samples and low accumulation of heat. (SFS)
Enthalpimetry Modeling

"Determination Of Water In Organic Solvents By The Karl Fischer Method Under Flow Injection Conditions"
Chem. Tech. 1987 Volume 39, Issue 1 Pages 25-28
Muller, H.;Seelisch, J.;Kirsch, D.

Abstract: A flow-injection procedure for the determination of water by using Karl Fischer reagents and spectrophotometric indication is described. Water contents (0.05%(v/v) water) in alcohols and ketones can be determined at a rate of 120 samples/h with good precision (relative standard deviation ~1%). The method was calibrated against the Karl Fischer method with dead-stop indication and a good correlation was obtained between the two methods. (SFS)
Water Organic compound Karl Fischer analysis Method comparison

"Direct Potentiometric Measure Of The Fluoride, Chloride, Cyanide, Sulfide, Nitrate, And Ammonium Ions In Waters And Waste Waters"
Chem. Tech. 1975 Volume 4, Issue 5 Pages 183-188
Oehme, Friedrich

Abstract: Photometric and direct potentiometric methods for the determination of the more important ions present in waters and effluents are compared, and the fundamentals and possibilities of potentiometric ion measurements are reviewed. The construction, suitablity, stability, reproducibility, and selectivity of ion-sensitive electrodes used in continuous measuring application are discussed. 28 references (SFS)
Fluoride Chloride Cyanide Sulfide Nitrate Ammonium Water Potentiometry Apparatus Detector