Determination of the heterogeneity of poly-p-phenylene terephthalamide solutions in sulfuric acid from the turbidity spectrum

1980 ◽  
Vol 11 (3) ◽  
pp. 252-254
Author(s):  
L. V. Prozorov ◽  
V. N. Smirnova ◽  
Z. S. Khanin ◽  
A. V. Volokhina ◽  
V. I. Klenin ◽  
...  
Keyword(s):  
Sulfuric Acid ◽  
Turbidity Spectrum

Improved Method for the Determination of Ethylenebisdithiocarbamate Residues in Plants, Fruits, and Vegetables

1967 ◽  
Vol 50 (5) ◽  
pp. 1102-1108
Author(s):  
Charles F Gordon ◽  
Richard J Schuckert ◽  
William E Bornak
Keyword(s):  
Sulfuric Acid ◽  
Fruits And Vegetables ◽  
Analytical Procedure ◽  
Improved Method ◽  
Modified Method ◽  
Fungicide Residues ◽  
Crop Types ◽  
Large Representative

Abstract A modified method for the determination of dithiocarbamate fungicide residues on crops is presented. A large representative subsample of the frozen crop is blended in ice-cold deaerated water and an aliquot of the homogenate is added to the analytical apparatus containing hot 5 0% sulfuric acid. Dithiocarbamates are decomposed to evolve CS2 which is removed by a continuous gentle air-sweep from the digestion flask. Variations in technique allow the analysis of dithiocarbamate fungicide residues in several ranges, 1-10, 10-200, and 200-1000 /ig maneb. Recoveries from a wide variety of crops averaged 70 to 103%. Certain crop types present low recoveries and/or high apparent control values, but modifications in the analytical procedure are successful in solving these problems.

Simultaneous radiometric determination of uranium and thorium in sulfuric acid solutions

1972 ◽  
Vol 31 (6) ◽  
pp. 1425-1427 ◽  
Author(s):  
V. V. Anosov ◽  
N. I. Gavrilov ◽  
T. P. Smelkova
Keyword(s):  
Sulfuric Acid ◽  
Acid Solutions ◽  
Sulfuric Acid Solutions ◽  
Radiometric Determination

A Headspace Gas Chromatographic Method for Determination of Formic acid Content in Isosulfan Blue and in Various Drugs

2021 ◽  
Vol 37 (2) ◽  
pp. 321-329
Author(s):  
Nilesh Takale ◽  
Neelakandan Kaliyaperumal ◽  
Gopalakrishnan Mannathusamy ◽  
Rajarajan Govindasamy
Keyword(s):  
Sulfuric Acid ◽  
Formic Acid ◽  
Chromatographic Method ◽  
Isopropyl Alcohol ◽  
Class Iii ◽  
Drug Substances ◽  
Headspace Gas ◽  
Concentrated Sulfuric Acid ◽  
Gas Chromatographic Method

The Pharmaceutical industry uses formic acid in the manufacturing of various drug substances or API. At the time of manufacturing of API formic acid is use as an oxidizing agent. Formic acid is the simplest carboxylic acid. It also called methanoic acid.Formic acid present in API at high concentrations is very hazardous but in low concentrations is very beneficial. The developed and validated method was short, precise, cost effective and reproducible with FID detector and easy to use. The method is a selective and superficial analytical method for determination of formic acid in different drug substances. We report here the development and validation study of headspace gas chromatographic method to determine formic acid in different drug substances we are reported here. As per this method, the drug sample was dissolved in 0.1% (v/v) of concentrated sulfuric acid in isopropyl alcohol (IPA) in a GC headspace vial and 0.1% (v/v) of concentrated sulfuric acid in isopropyl alcohol used as a diluent. A AB-Inowax capillary column (30 m x 0.32 mm I.D. and 0.5 µm film thickness) was used under gradient conditions with FID. The formic acid peak was well separated from all other solvents that are used in synthesis of particular drug substance. The LOD and LOQof the method for formic acid are 82 ppm and 249 ppm respectively. Formic acid are low toxic class-III solvent as per ICH guideline.

A new spectrophotometric method for the micro determination of sulfuric acid esters in sulfatide fractions

1960 ◽  
Vol 48 (4) ◽  
pp. 502-509 ◽  
Author(s):  
Frank J. Witmer ◽  
James H. Austin
Keyword(s):  
Sulfuric Acid ◽  
Spectrophotometric Method ◽  
Acid Esters

Determination of Gaseous Sulfuric Acid and Sulfur Dioxide in Stack Gases

2017 ◽  
pp. 523-528
Author(s):  
James P. Lodge
Keyword(s):  
Sulfuric Acid ◽  
Sulfur Dioxide

scholarly journals FIA for the determination of higher concentration sulfuric acid by means of chemiluminescent enhancement with natural reddish dye in red rose petals.

1992 ◽  
Vol 41 (12) ◽  
pp. 617-625
Author(s):  
Mikita ISHII ◽  
Tooru TAKAHASHI ◽  
Shinichi BABASAKI
Keyword(s):  
Sulfuric Acid ◽  
Rose Petals

A sensor for the in situ determination of acidity levels in concentrated sulfuric acid

1999 ◽  
Vol 365 (4) ◽  
pp. 310-313
Author(s):  
B. Hammouti ◽  
H. Oudda ◽  
A. El Maslout ◽  
A. Benayada
Keyword(s):  
Sulfuric Acid ◽  
Concentrated Sulfuric Acid

Experimental determination of the passive/active transition for iron in 1-M sulfuric acid

1984 ◽  
Author(s):  
P. Russell ◽  
J. Newman
Keyword(s):  
Sulfuric Acid ◽  
Experimental Determination ◽  
Active Transition
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