Automated Determination of Zoalene in Feeds

1969 ◽  
Vol 52 (1) ◽  
pp. 93-101
Author(s):  
Howard L Christopherson
Keyword(s):  
Steady State ◽  
Sampling Rate ◽  
Color Reaction ◽  
Good Resolution ◽  
Automatic Correction ◽  
Compressed Gas ◽  
Aoac Method ◽  
Mixing Noise ◽  
Automated Determination

Abstract Elimination of 5 steps (a quantitative wash, dilution to 100 nil, spiking an aliquot, evaporation to dryness, and dissolution in dimcthylformamide) in the official AOAC method for Zoalene in feeds and automation of the color reaction with cthylenediaminc using Technicon equipment has increased speed and precision several fold without significantly changing the chemistry of the AOAC method. A sampling rate of 80 analyses per hour with nearly steady state peak heights, good resolution hetween peaks, and low mixing noise was achieved hy using modified fittings and compressed gas for solution segmentation. A differential colorimeter provides automatic correction for feed blanks.

Mass Phenotyping of Isoniazid Inactivators by Automated Determination of Acetylisoniazid in Urine

1974 ◽  
Vol 20 (6) ◽  
pp. 639-641 ◽  
Author(s):  
P Varughese ◽  
E J Hamilton ◽  
L Eidus
Keyword(s):  
Aqueous Solution ◽  
Sampling Rate ◽  
Color Reaction ◽  
Automated Determination

Abstract An automated procedure is described for phenotyping isoniazid inactivators. The method is based on the color reaction produced by N-acetylisoniazid in aqueous solution, as described by Eidus and Hamilton [Amer. Rev. Resp. Dis. 89, 587 (1964)]. Maximum sampling rate is 60 samples per hour. Results of this procedure correlated well (r = 0.987) with those of a manual phenotyping method.

Automated Determination of Urinary Inorganic Sulfates with the "AutoAnalyzer"

1971 ◽  
Vol 17 (12) ◽  
pp. 1183-1185 ◽  
Author(s):  
J P Dieu
Keyword(s):  
Barium Sulfate ◽  
Sampling Rate ◽  
Turbidimetric Method ◽  
Automated Determination

Abstract A turbidimetric method for inorganic sulfates in urine, based on the precipitation of barium sulfate, is adapted to the AutoAnalyzer. Coating of the flowcell with BaSO4 is avoided by an inter-sample air rinsing. Sampling rate is 40/h.

Critical Evaluation of the AOAC Method of Analysis for Nitrite in Meat

1973 ◽  
Vol 56 (4) ◽  
pp. 922-925 ◽  
Author(s):  
Rosemary A Nicholas ◽  
Jay B Fox
Keyword(s):  
Mercuric Chloride ◽  
Critical Evaluation ◽  
Color Reaction ◽  
Meat Sample ◽  
Official Method ◽  
Griess Reagent ◽  
Initial Dilution ◽  
Alternative Procedures ◽  
Aoac Method

Abstract Results of studies on the effects of 5 alternative procedures of sample preparation are presented. The standard deviations for the methods were 0.00505, 0.00142, 0.00307, 0.00265, and 0.00243, with the AOAC method giving the highest values for nitrite. The effects of some variables on the determination of the nitrite content of meat by the official method were also studied. These variables include the addition of mercuric chloride, duration of heating, rate of color reaction, and reagent preparation. The nitrite concentration as measured by the AOAC method varied with the initial dilution of meat sample. A number of compounds were added to the Griess reagent and nitrite solution to see whether they would affect the reaction. Reductants were found to interfere consistently. Suggestions for simplifying and improving the official method are made. These include omitting mercuric chloride, recrystallizing 1-naphthylamine before using, and allowing only 25 min for the completion of the color reaction, using a higher concentration of Griess reagent.

Studies of the Determination of Fluoride in Vegetation Samples

1989 ◽  
Vol 42 (7) ◽  
pp. 1125 ◽  
Author(s):  
RW Cattrall ◽  
WL Chek ◽  
IC Hamilton ◽  
PJ Watkins
Keyword(s):  
Steady State ◽  
Electrode Potential ◽  
Acid Leaching ◽  
Indigenous Australian ◽  
Ground Sample ◽  
Leaf Material ◽  
Aoac Method ◽  
Fluoride Electrode ◽  
Vegetation Samples

The use of the Association of Official Analytical Chemists (AOAC) First Action method, which is based on acid leaching of the dried, ground sample, is examined for its suitability for the recovery of fluoride from leaf material derived predominantly from indigenous Australian trees. The method is compared with two independent but time-consuming procedures based on oxygen pyrolysis and pyrohydrolysis. These two reference methods give internally consistent results and provide a sound basis on which to critically examine the AOAC First Action method. It is concluded that the AOAC method, in general, gives reliable and rapid results, although two of the species studied showed a low fluoride recovery. The AOAC method uses a fluoride electrode finish which is slow for solutions of low concentration. A graphical procedure is examined for estimating the steady-state electrode potential; this procedure increases the speed of the analysis without affecting unduly the accuracy of the analysis.

Automated Determination of Ethanol and Wine Extract with Precision Density Meter, Automatic Sampler, and Programmable Calculator

1986 ◽  
Vol 69 (4) ◽  
pp. 709-711
Author(s):  
Jerry R Ruppert
Keyword(s):  
Polynomial Equation ◽  
Absolute Error ◽  
Degree Polynomial ◽  
Programmable Calculator ◽  
Wine Sample ◽  
Automatic Sampler ◽  
Aoac Method ◽  
The Absolute ◽  
Automated Determination

Abstract Use of density meters has become the preferred method in many alcohol beverage laboratories to determine the concentration of ethanol in wines and spirits. Density converted to SG (20/20) is also the basis of an official AOAC method to determine extract of wine. Automation of the latter procedure is inhibited by the necessity to access AOAC Table 52.008 to convert SG (20/20) of the dealcoholized wine sample to percentage of sucrose by weight. The author reduced the most commonly used portion of that table (1-30% sucrose by weight) to a third degree polynomial, enabling the use of a density meter, an automatic sampler, and a computer or programmable calculator to automatically determine alcoholic content and wine extract from a sample of wine and its distillate. The absolute error between AOAC Table 52.008 and the author’s polynomial equation is less than ± 0.002 percentage of sucrose by weight for the range 1-30% sucrose by weight.

Automated Determination of Thiamine (Vitamin B1) in Pharmaceutical Preparations

1971 ◽  
Vol 54 (5) ◽  
pp. 1164-1167
Author(s):  
Omer Pelletier ◽  
RenÉ Brassard
Keyword(s):  
Liver Extract ◽  
Vitamin B1 ◽  
Pharmaceutical Preparations ◽  
Manual Method ◽  
Automated Method ◽  
Thiamine Content ◽  
Aoac Method ◽  
Automated Determination

Abstract The chemical principles used for the determination of thiamine in pharmaceutical preparations by the official USP and AOAC methods were adapted to an automated flowthrough analyzer. The system could analyze 20 samples (including blanks) per hour. Thiamine extracts from 12 different multivitamin preparations were analyzed by one analyst on 5 different days by the automated method and the AOAC method. Both methods yielded comparable values for 10 of the preparations. The thiamine content of 2 preparations containing liver extract was found to be about 9% higher by the automated method than by the AOAC method. Further analysis of other samples of these 2 preparations containing liver extract showed that chromatography on Decalso did not change the results obtained by the automated method, but raised the results obtained by the manual method to a level comparable to the automated method. The AOAC method showed a tendency for a slightly higher reproducibility of assays.

Automated determination of carboxylic acids by anion-exchange chromatography with specific color reaction

1977 ◽  
Vol 49 (4) ◽  
pp. 655-658 ◽  
Author(s):  
Yasuhiko. Kasai ◽  
Takenori. Tanimura ◽  
Zenzo. Tamura ◽  
Yoshinori. Ozawa
Keyword(s):  
Anion Exchange ◽  
Carboxylic Acids ◽  
Anion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Color Reaction ◽  
Automated Determination

STEADY-STATE DETERMINATION OF FUEL-BOND NITROGEN IN DIESEL AND INDUSTRIAL GAS OIL

Clean Air ◽  
2007 ◽  
Vol 8 (4) ◽  
pp. 359-371
Author(s):  
A. Medeiros ◽  
R. Edenhofer ◽  
K. Lucka ◽  
H. Kohne
Keyword(s):  
Steady State ◽  
Gas Oil ◽  
State Determination

An Automated Procedure for the Determination of Ammonia in Tobacco

1972 ◽  
Vol 6 (4) ◽  
Author(s):  
P.F. Collins ◽  
W.W. Lawrence ◽  
J.F. Williams
Keyword(s):  
Standard Deviation ◽  
Relative Standard Deviation ◽  
Distillation Method ◽  
Relative Standard ◽  
Tobacco Sample ◽  
Automated Determination

AbstractA procedure for the automated determination of ammonia in tobacco has been developed. Ammonia is extracted from the ground tobacco sample with water and is determined with a Technicon Auto Analyser system which employs separation of the ammonia through volatilization followed by colourimetry using the phenate-hypochlorite reaction. The procedure has been applied to a variety of tobaccos containing from 0.02 to 0.5 % ammonia with an overall relative standard deviation of 2 %. The accuracy of the procedure as judged by recovery tests and by comparison to a manual distillation method is considered adequate

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