bluuebunny/crossref_metadata_2025_split huggingface dataset:
Use of Gas Chromatography in Distillery Research and Control
Authors: Debecze G I , Smith H F , Vaughn T E 
Published: February 2020

Abstract
Twelve volatile components commonly present in many whiskies can be determined directly by gas chromatography on four columns vinder specified conditions. Separalion and measurement of higher alcohols, separation of acetone from ethyl formate, measurements of four esters present, and proof of the absence of several components previously suspected to be present in distilled alcoholic beverages are described. Numerical values corresponding to the peaks are given for the components. Gas chromatograms combined with conventional chemical analysis give the best identification of bottled goods
Collaborative Study of a Method for the Identification of Afiatoxin B1 by Derivative Formation
Authors: Stoloff Leonard 
Published: February 2020

Abstract
A modification of the Andrellos procedure for identification of afiatoxin B1 was studied collaboratively in 19 laboratories. The procedure, based on the altered chromatographic behavior of the afiatoxin after reactions with trifluoroacetic acid, formic acid/thionyl chloride, and glacial acetic acid/thionyl chloride, was modified by an improved silica gel column cleanup and a clearer definition of sources of difficulty. Each collaborator examined 3 extract samples: two naturally contaminated with 5 μg afiatoxin B1/sample, and one aflatoxin-free extract to which an afiatoxin B2 artifact was added. No false identifications were made. Sixteen laboratories obtained reasonably good results with the trifluoroacetic acid and formic acid/thionyl chloride reagents. Twelve laboratories obtained reasonably good results with the acetic acid/thionyl chloride reagent but there was general difficulty with a side reaction assumed to be caused by inability to maintain anhydrous conditions. The method was recommended for adoption as official, first action.
Identification of Bullet Holes by Residue Transfer
Authors: Schlesinger H L , Hoffman C M , Pro M J 
Published: February 2020

Abstract
Antimony and copper residues deposited on the bullet surface after explosion of a pistol cartridge were measured by neutron activation analysis. The amount of residue wiped from the bullet surface upon passage through various target materials was determined. Correlations were found between the residue deposited on the target material and the bullet jacketing, caliber, and configuration
Residues in Poultry Tissues from Low Level Feeding of Five
Chlorinated Hydrocarbon Insecticides to Hens
Authors: Cummings J G , Eidelman M , Turner V , Reed D , Zee K T , Cook R E 
Published: February 2020

Abstract
Lindane, heptachlor epoxide, dieldrin, endrin, and DDT were fed in combination at 3 levels (0.05, 0.15, and 0.45 ppm) to hens, and residues were determined in abdominal fat, breast muscle, and livers by electron capture gas chromatography. Tissue samples were taken from birds at each feeding level and a control at regular intervals during a 5-month period which included 2 weeks pre-fortification, 14 weeks on the fortified feed, and 1 month withdrawal. Graphic data on fat and breast muscle show the increase of residues with time to an approximate plateau and the rate of decline. The greatest storage was in the fatty tissue where dieldrin and heptachlor epoxide attained a level approximately ten times the respective levels in the feed; endrin, p,p'- DDT, and lindane stored to a lesser degree. All residues in breast tissue were &lt; 0.1 ppm, but the feeding levels were clearly delineated. AH residues in liver were &lt; 1.0 ppm. The respective storage tendencies of the pesticides were the same in all tissues. A significant increase in the DDT metabolites, DDE and DDD, were observed. Lindane residues showed the greatest decline rate.
Determination of Aphids in Hops
Authors: Wright R G 
Published: February 2020

Abstract
The flotation procedure for determining aphids in hops has been improved over the previously described method (Method A, This Journal, 45, 670 (1962)) by the addition of an iodine staining technique to increase visibility of the aphids and a change in the counting procedure to include, as a whole aphid, any aphid part containing a head
Detection of Leaf Miners in Canned Spinach and
Turnip Greens
Authors: Brown Robert F 
Published: February 2020

Abstract
Comparative analyses with existing flotation and heavy filth methods indicate that a sieving, staining, and bleaching technique will give higher yield of spinach leaf miner and certain other arthropod filth. However, in some cases aphids were recovered in greater quantity with the flotation procedure. The sieving, staining, and bleaching technique is less laborious and less timeconsuming than the other methods studied
Improved Infrared Method for Carbaryl (Sevin) in
Commercial Formulations
Authors: Kovacs Martin F 
Published: February 2020

Abstract
The method described measures the infrared absorption bands of carbaryl at 5.75 and 8.94 ji after extraction from commercial formulations with chloroform. The products analyzed include Sevin as 5% dust, 50% dust, 50% wettable powder, and 85% sprayable powder. This method is recommended for adoption as official, first action
Collaborative Study of a Titrimetric Method for the Assay of
Amitrole Formulations
Authors: Bishop J Russell 
Published: February 2020

Abstract
titrimetric method for the assay of dry and liquid amitrole formulations was studied by 10 collaborators. In the method, acid is added to the prepared amitrole sample, the solution is titrated potentiometrically with standard alkali, and the amitrole content is measured as the amount of alkali consumed between the first and second inflection points. Collaborative results on standard samples of a dry 90% formulation, a dry 50% formulation, and a liquid 2 lb/gallon formulation showed good agreement between samples and laboratories. Statistical analyses of the results were satisfactory, and the method for the assay of amitrole formulations is recommended for adoption as official, first action
Separation, Identification, and Measurement of DDT and Its
Metabolites
Authors: Siewierski Marie , Helrich Kenneth 
Published: February 2020

Abstract
A system that combines gas and thin layer chromatography with infrared spectrophotometry has been devised for the separation, quantitation, and tentative identification of DDT and twelve of its possible reaction products. The system gives satisfactory results by all three methods and is valuable for investigation of the fate of DDT
Method for Residues of Zytron,® O-2,4-Dichlorophenyl O-methyl isopropylphosphoramidothioate, in Chicken Tissues and Eggs
Authors: Ivey M C , Claborn H V , Brinkman Barton 
Published: February 2020

Abstract
A gas chromatograph equipped with an electron capture detector provided a highly sensitive method for determining residues of the phosphorothioate Zytron in eggs and in the body tissues of chickens. An extraction and cleanup procedure made possible the detection of 0.005 ppm of Zytron and gave recoveries of 86—95% from the various tissues.
Quantitative Determination of Isoniazid (INH) and p-Aminosalicylic Acid (PAS)
Authors: Turczan John W 
Published: February 2020

Abstract
A procedure has been developed for the analysis of a combination of PAS with INH in tablets. This procedure is faster and more specific than the current AOAC assay. In the method, finely powdered tablets are dissolved in methanolic HCl. INH is determined by polarography, and PAS is determined by UV spectrophotometry.
Determination of Hydrocodone in Mixtures with Antihistamines
Authors: Doyle Thomas D 
Published: February 2020

Abstract
A modification of the official method for the analysis of hydrocodone in mixtures was studied collaboratively in 1965, but the results were invalidated by deterioration of hydrocodone in the sample sirup. The present study was designed to prevent this deterioration. Seven of the 9 collaborators report recoveries averaging 99.9%. The method is recommended for adoption as official, first action.
Infrared Determination of Piloearpine in Ophthalmic Solutions
Authors: Roberts James I 
Published: February 2020

Abstract
Official methods for piloearpine salts are aqueous and nonaqueous titrations that lack specificity. In the proposed method, piloearpine is extracted from the sample with chloroform and determined by infrared spectrophotometry with the absorbance maximum of 9 μ. Identity of the piloearpine is confirmed by comparing spectra of sample and standard between 5 and 11 μ. Recoveries of piloearpine from simple aqueous solutions of the nitrate ranged from 99 to 104%. Analysis of 9 commercial products declaring 0.5—4% piloearpine salt showed good precision between duplicates. Further study is recommended.
A Collaborative Study of the Analysis of Salicylic Acid and Benzoic Acid
Authors: Weber John D 
Published: February 2020

Abstract
A collaborative study was made on the analysis of benzoic acid and salicylic acid. The acids were separated by trapping salicylic acid on a ferric chloride-urea column and benzoic acid on a sodium bicarbonate column. Average recoveries were 101.9 ± 3.3% and 101.8 ± 3.0% salicylic acid and 100.5 ± 1.8% and 100.6 ± 1.8% benzoic acid for a liquid and solid sample, respectively. The method is recommended for adoption as official, first action.
Nuclear Magnetic Resonance Methods for the Analysis of Pharmaceuticals
Authors: Alexander Thomas G , Koch Stanley A 
Published: February 2020

Abstract
A collaborative study was conducted to determine the interlaboratory variation that would result from instrumental error alone. Six collaborators assayed sealed aliquots of solutions and measured peak areas by the instruments' electronic integrators. Average collaborative values deviated as much as 8% from the true value. Further work is recommended in an effort to reduce any deviation that may result from variation in either sample or technique.
Differences in Potassium Values Determined by Official AOAC Extraction Procedures
Authors: Rexroad Paul R , Gehrke Charles W 
Published: February 2020

Abstract
An investigation of a major difference in a special sample showed the reason for the potassium value differences in many routine fertilizer samples. Lower K2O values by AOAC official carbonate extraction method 2.079(a) as compared with AOAC official oxalate extraction method 2.070(a) were found consistently for 17 typical mixed fertilizer samples investigated. An average lower absolute difference of 0.4% K2O was found on the typical mixed fertilizers by carbonate extraction. Studies show that this difference is associated with the impurities in fertilizer grade phosphate raw materials, particularly the varying solubility of the (Fe,Al) (NH4,K,H) phosphates.
Gas Chromatographic Determination of Residual Hydrocarbon Solvents in Solvent-Extracted Edible Oils
Authors: Watts James O , Holswade Wendell 
Published: February 2020

Abstract
A rapid gas chromatographic survey method has been developed for the determination of residual hydrocarbon solvents potentially present in solvent-extracted edible oils. No prior cleanup or separation step is necessary. The oil samples are injected directly onto a GLC column containing 10% didodecyl phthalate liquid phase on 60—80 mesh Chromosorb P. Isomeric hexanes, isomeric heptanes, benzene, and toluene can be resolved in 25 minutes. Based on recovery studies, total residual isomeric hexane extraction solvent can be determined at 22—109 ppm with an average recovery of 92 ± 2.1%, and total residual isomeric heptane extraction solvent can be determined at 23—117 ppm with an average recovery of 90 ± 3.5% ; n-hexane and n-heptane are used as external standards. At the lowest levels of sensitivity, 22 ppm of total isomeric hexanes and 23 ppm of total isomeric heptanes, the observed average recoveries of 91 ± 2.5% and 92 ± 3.4%, respectively, are adequate. Although quantitative estimation is not practicable at lower levels, the presence of 10 ppm and probably less is discernible on the gas chromatograms. Quantitative recovery data for benzene and toluene have not been included, but the characteristics of their GLC peaks indicate the method is more sensitive for these aromatic impurities than for the aliphatic extraction solvents
Determining the Yeast Count in Maple Sirup and a Collaborative Study of the Methods and Sampling Techniques
Authors: Kissinger John C 
Published: February 2020

Abstract
Techniques for sampling and a method for determining the yeast count in maple sirup have been studied collaboratively in 22 laboratories. Statistical analysis of collaborators' results indicated that variation in shipping conditions had an adverse effect on the sirup samples and that difficulties in preparing homogeneous cell suspensions in the sirup prior to subsampling caused wide variation in counts. Studies will continue
Activity of Phenol, Ethyl Alcohol, and Isopropyl Alcohol in the AOAC Official, First Action Tuberculocidal Test
Authors: Shaffer C H , Ortenzio L F , Stuart L S 
Published: February 2020

Abstract
The reproducibility of results in the test procedure against the pure chemical phenol, using the test organism Mycobacterium tuberculosis var. bovis (BCG), was investigated. The method showed a remarkable degree of precision. The tuberculocidal activity of various concentrations of ethyl alcohol and isopropyl alcohol was also investigated, since these two chemicals have been widely used as tuberculocidal agents.
Collaborative Study of the Determination of uric Acid in Flour
Authors: Sen N P 
Published: February 2020

Abstract
A collaborative study of an enzymaticultraviolet method for determining uric acid in flour was made by 10 laboratories on 3 flour samples containing varied proportions of infested flour and one sample containing a known amount of added uric acid. The mean recovery of the added uric acid (16.91 mg/100 g) was 103%. The precision and accuracy of the collaborative results were within reasonable range for an enzymatic method.
Determination of Ascorbic Acid in Enriched Evaporated Milk
Authors: Pelletier O 
Published: February 2020

Abstract
Ascorbic acid can be determined in enriched evaporated milk by titration with 2,6-dichIoroindophenol. Most of the interfering substances are removed by precipitation with an acetic acid-metaphosphoric acid solution. Blank titrations obtained after condensing ascorbic acid with formaldehyde are used to correct for traces of interfering substances remaining in solution. Recoveries of ascorbic acid added to milk were 98.5% (coefficient of variation, 1.9). In a collaborative assay involving six analysts, the coefficient of variation was about 2% for one analyst on any day and 3.5% among analysts "on any day.
Procedure for Nine Organothiophosphate Pesticide Residues on Fruits and Vegetables, Using Microcoulometric Gas Chromatography
Authors: Nelson Richard C 
Published: February 2020

Abstract
A method, using microcoulometric gas chromatography (sulfur dioxide detector), is proposed for determining 9 organothiophosphate pesticide residues in fruits and vegetables. Extraction and cleanup principles and procedures are those used in the Mills-Onley-Gaither method for chlorinated pesticides, with modifications, particularly in the Florisil cleanup step. Recoveries of the compounds (sulfotepp, Thimet, diazinon, Di-Syston, methyl parathion, parathion, ethion, Trithion, and EI'IV) from crops fortified just prior to extraction ranged from 73 to 109%, with an overall average of 92%. Average recoveries of individual thiophosphates ranged from 82 to 99%. Recoveries were made at low (0.1— 0.2), intermediate (0.5), and high (2.0- 3.0) ppm levels. Cleanup on all crops tested was adequate for the detector used. In addition to the above compounds, malathion was quantitatively cluted from the Florisil column with an additional eluting mixture of higher polarity. Studies of the method should be continued to include both petroleum ether- and water-soluble compounds, and additional column packings will be investigated.
Benzoates in Foods
Authors: Lewis Matthew H , Schwartzman George 
Published: February 2020

Abstract
A collaborative study was conducted on a steam distillation-TLC method for benzoates in foods. Prior to measurement using 5 cm micro cells, the preservatives are separated from the food sample by steam distillation, and extracted from the distillate by CHCl3-ether shake-out. The samples were spotted on a thin layer plate (silica gel GF254 and kieselguhr G), the chromatogram was developed, and the material was recovered from the plate by extracting with ethanol. This procedure easily detects 0.1 ppm benzoate in foods. The method is recommended for adoption as official, first action with further work to be done on the determination of hydroxybenzoates, propionates, and other preservatives.
Improved Method for the Determination of Ethylenebisdithiocarbamate Residues in Plants, Fruits, and Vegetables
Authors: Gordon Charles F , Schuckert Richard J , Bornak William E 
Published: February 2020

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.
Determination of l-Phenylazo-2-naphthol in D&C Red No. 17
Authors: Molitor John C 
Published: February 2020

Abstract
A thin layer chromatographic procedure is presented in which l-phenyIazo-2-naphthol (PAN) and an unidentified red substance are separated from D&C Red. No. 17 (l-p-phenylazophenylazo-2-naphthoI). PAN is dissolved from the absorbent and determined spectrophotometrically. Recoveries from samples of known composition ranged from 92 to 105%. The PAN content of commercial samples analyzed by this procedure ranged from 0.06 to 1.2%. Unsuccessful attempts to identify the red substance are discussed.
The New Florisil: A Statistical Evaluation For Chlorinated Pesticides
Authors: Beckman Herman , Carroll Kenneth , Thornburg Wayne , Vetro R I , Smith R D , Mittler Abe , Kecskes M B , Bevenue Arthur , Kawano Yoshihiko 
Published: February 2020

Abstract
A multi-laboratory study to evaluate the new Florisil PR was made with several chlorinated hydrocarbon insecticides and two representative crops. A computer program was used to analyze and compare the data between laboratories, between batches of Florisil PR, and between elution of standards alone and in the presence of crops. A comparison was also made of the elution patterns of "standard" Florisil and Florisil PR. Conclusions were drawn as to the most significant sources of error and the factors contributing to these. The computed data indicated that (1) there were greater differences in results due to variations between laboratories than due to any other cause; (2) greater differences in mean elution values were found when crop materials were present than with standards alone; (3) the least amount of variation observed was associated with differences between Florisil PR batches; and (4) six samples of "standard" Florisil showed that consistency of each batch was not always adequate for routine analysis
A Survey of Organic Chloride Impurities in Food Grade Hydrochloric Acid
Authors: Cummings J G , Zee K T 
Published: February 2020

Abstract
Results are given of a survey on organic chloride impurities in hydrochloric acid samples obtained from food manufacturing plants. Total organic extractible chloride found in the acids ranged from 3.9 to 10.2 ppm. A microcoulometric method of analysis for total chlorides was developed in which samples are extracted with petroleum ether, burned in a SchÖniger oxygen flask, and determined microcoulometrically. The more volatile impurities appear from GLC examination to be various common chlorinated aliphatics. No chlorinated pesticides were found
Determination of Molybdenum in Fertilizers by Atomic Absorption Spectrophotometry
Authors: Hoover William L , Dtjren Sonja C 
Published: February 2020

Abstract
A procedure for determining low levels of molybdenum in fertilizers by atomic absorption is proposed. With potassium thiocyanate as complexing agent, molybdenum is extracted in an isoamyl alcohol fraction to separate the fraction containing molybdenum from the water-soluble fraction containing materials that would interfere in the atomic absorption procedure. However, the procedure cannot be used with samples that have high concentrations of iron. Tests on the recovery of molybdenum in four fertilizers indicate that the procedure is reliable to levels as low as 2.5 ppm of molybdenum
Fatty Acid Composition of Palm Kernel, Illipe, and Shea Nut Oils by Urea Fractionation and Programmed Temperature Gas Chromatography
Authors: Iverson John L , Harrill Prince G 
Published: February 2020

Abstract
The detection of C6 to C28 fatty acids is possible when their methyl esters are concentrated by urea fractionation so that esters with similar gas chromatographic retention times are in different fractions. By modified programmed temperature gas chromatographic techniques, it is possible to detect and estimate fatty acids present in trace amounts (0.1 to 0.001%) in palm kernel, shea nut, and illipe oils. The odd and even chain length saturated fatty acids from C6 to C28 were detected. The odd and even chain length mono-unsaturates from C14 to C24 and the even chain length dienes from C14 to C24 were detected
Gas Chromatographic Determination of Chlormadinone Acetate in Feeds and Premixes
Authors: Koons J R , Scroggs R E 
Published: February 2020

Abstract
A method for determining chlormadinone acetate, a progestational steroid used for animal estrus control* involves extraction of the feed samples with dichloromethane and chromatography of the extracts on alumina to remove interfering materials. Extracts of premixes do not require purification. Chlormadinone acetate is measured by electron capture gas chromatography. Recoveries average 90 and 100% for feeds and premixes, respectively. Confidence limits (95%) for a single measurement on a sample (0.0022%) are ± 14%
Analysis of Preparations Containing LSD (N,N—Diethyl d—Lysergamide)
Authors: Martin Robert J , Alexander Thomas G 
Published: February 2020

Abstract
LSD (diethylamide of d-lysergic acid) can be detected by its fluorescence under ultraviolet light and by the production of a deep blue color when it is treated with a solution of p-dimethylaminobenzaldehyde and ferric chloride in sulfuric acid. LSD in an acid aqueous system has a peak maximum at about 312 m/j. This paper describes methods, adapted and modified in our laboratories, which are based on the above chemical properties of LSD. The methods include separatory funnel and column cleanup procedures, fluorescence tests, thin layer chromatography, separation of iso-LSD from LSD, and infrared identification
Assessment of the Naphthylazo-naphthylamine Method for
the Determination of Nitrate and Nitrite
Authors: Kamm Len , Bray D F , Coffin D E 
Published: February 2020

Abstract
The 1-naphthylazo-naphthylamine method for nitrate and nitrite, reported in 1965, was subjected to specific experiments statistically designed to determine more precisely the precision of the method. Experimental designs included the following: standard nitrite curve, stability of 1-naphthylazo- naphthylamino dye, reduction of nitrate to nitrite by the cadmium column, reproducibility of results comparing natural foodstuffs with pure solutions, and collaborative study on food samples. The statistical data obtained indicate that the method is consistent and precise