bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Use of a Solid Support for the Extraction of Chlorinated Pesticides from Large Quantities of Fats and Oils
Authors: Rogers W Michael 
Published: February 2020

Abstract
A solid support with a large surface area and a high affinity for oils has been used as a vehicle to suspend extracted fats and oils on its surface. Extraction of the fat-coated particles with an acetone-acetonitrile solvent mixture allows a quantitative isolation of chlorinated pesticide residues with a co-extraction of only about 1 g fat from a 30 g original sample. Recoveries of 5 chlorinated pesticides added to corn oil and butterfat samples at the 0.01 and 0.30 levels ranged from 83 to 100%. Satisfactory agreement between the proposed method and the official AOAC petroleum ether-acetonitrile partitioning method is obtained for various high fat products containing incurred chlorinated pesticide residues. The increased sensitivity and speed of the described method allow the rapid performance of qualitative, quantitative, and confirmatory analyses on a single sample.
Vertical Plate Gel Electrophoresis for the Differentiation of Fish and Shellfish Species
Authors: Coduri R J , Rand A G 
Published: February 2020

Abstract
The vertical plate polyacrylamide gel electrophoresis technique described for differentiation of meat was applied to fresh and frozen fish and shellfish species. A single 7% Cyanogum gel containing mercaptoethanol, in conjunction with a tris-chloride, tris-glycine discontinuous buffer system, produced satisfactory resolution of fish and shellfish species extracts. The electrophoretic patterns were obtained by direct analysis of the proteins extracted with a tris-chloride-10% glucose extraction buffer at pH 6.7. This technique can also be used to detect substitution of one fish or shellfish species for another.
Missouri Automated Nitrogen Method (MANM) for Fertilizers
Authors: Gehrke Charles W , Killingley John S , Wall Larry L 
Published: February 2020

Abstract
An automated spectrophotometric method, utilizing Technicon AutoAnalyzer modules, has been developed to determine total nitrogen in fertilizers containing only ammoniacal, nitrate , and urea nitrogen. This colorimetric system employs the Berthelot ammoniaphenate- hypochlorite reaction. A homogeneous chromous/titanous reduction system for the automatic reduction of nitrates was interfaced with the digestion unit and color development manifold, resulting in a total nitrogen system for fertilizers with an effective analysis r a t e of 20-25 samples/hr. A new sample retrieval system removes digested samples from the helix. The totally automated system was optimized to obtain t h e highest sensitivity for nitrogen. Data were compared for 458 samples analyzed by the automated method and the comprehensive nitrogen method (CNM), 2.053–2.054. The average difference between the 2 methods (MANM – CNM) was +0.04% nitrogen. The average relative difference was 1.12%. The average value for 140 samples of KNO3 primary standard analyzed by the MANM was 13.84% nitrogen (theoretical content 13.85%). The results of these standards ranged from 13.58 to 14.14% nitrogen and the standard deviation was 0.11%. The relative standard deviation was 0.80%. Of fertilizer samples received for analysis, less than 1% contained insoluble organic nitrogenous material which was unsuitable for analysis by the MANM. These few samples were not included in the statistical evaluation. The MANM is rapid, accurate, and precise and is a convenient and dependable automated method for the determination of total nitrogen in fertilizers containing only ammoniacal, nitrate , and urea nitrogen.
Modification of the Interpretation Section of Cryoscopic Methods for the Determination of the Freezing Point Value of Milk
Authors: Henningson K W 
Published: February 2020

Abstract
In 1969 the Interpretation of the freezing point value of milk was added as official first action to the official final action thermistor and Hortvel cryoscopic methods for the determination of the freezing point value of milk. During the ensuing year several State regulatory agencies indicated problems with 2 sections of the Interpretation, specifically, the 48 hr time limit for obtaining authentic , confirmatory samples of herd milk and/or the 0.010 difference permitted between the freezing point values of samples designated presumptive added water and authentic , confirmatory samples of herd milk. A survey of North American regulatory agencies was conducted to evaluate the extent of these problems. Twenty of the 41 regulatory agencies responding to the survey indicated that 48 hr was too short a time limit, 16 agencies indicated that the 48 hr was satisfactory, and 5 agencies declined to express an opinion. Six agencies indicated that the 0.010° difference permitted was too great, 29 agencies indicated the 0.010° difference permitted was satisfactory, 1 agency found the question inappropriate, and 5 agencies declined to express an opinion. No regulatory agency indicated other problems dealing with the Interpretation.
Collaborative Study of a New Method for the Extraction of Post-Milling Light Filth from High Bran Breads
Authors: Miller Mary T 
Published: February 2020

Abstract
A new method has been developed which utilizes the autoclave for an acid hydrolysis, followed by defatting with chloroform and alcohol or isopropanol and finally flotation of the filth elements in an HCl-ethanol or isopropanol medium. Collaborative study results give clean papers and good recoveries and the method has no critically timed steps. The method has been adopted as official first action to replace 40.037 and 40.038 for extraction of light filth from high bran breads.
Confirmation of Pesticide Residue Identity. I. Derivative Formation for the Confirmation of Photoproducts of Endrin: Hexachloro- and Pentachloro-ketone Pesticide Residues by Gas Chromatography
Authors: Chau Alfred S Y 
Published: February 2020

Abstract
Chemical conversions followed by GLC analysis are described for the confirmation of residues of 2 photoproducts of endrin, ketones I and II, in water and water-borne samples. These endrin degradation products were treated with potassium tert. -butoxide in tert.-butanol, followed by subsequent silylation or acetylation to the corresponding silyl ether or acetate. By this procedure, levels as low as 0.02- 0.03 ppm of these residues in 25 g fish sample extract or 0.01 ppb in 1 L water extract can be identified. The use of ehromous chloride to confirm these residues is also discussed. GLC data are given for some organochlorinated pesticides and their derivatives on a column of DC-ll/QF-1 and OV-101/OV-210.
Soil Moisture Influence on Treatment and Extraction of DDT from Soils
Authors: Nash R G , Harris W G 
Published: February 2020

Abstract
An investigation was conducted to determine techniques which prevented p,p’-DDT conversion to p,p’-DDE during (a) extraction of highly alkaline soils and (b) DDT treatment of highly alkaline soils. Moistening soils to near field capacity reduced DDT conversion to DDE during treatment and a new column extraction method was developed which prevented further conversion during extraction. Column extraction is more rapid than Soxhlet or shake extraction and requires less expensive equipment. However, column extraction was less efficient: about 4% DDT remained after extraction of incubated soils, whereas only about 1% remained in Soxhlet-extracted soils, except for clay soils in which both methods of extraction were low. Alkaline soils apparently can be extracted safely with either Soxhlet or column extraction without conversion of DDT to DDE, providing the soils have equilibrated in a moist condition.
Proposed Source of Chick Edema Factor
Authors: Metcalfe L D 
Published: February 2020

Abstract
Possible sources of contamination of fat by chlorophenols, precursors of chlorinated benzo- p-dioxins, are reviewed. Toxic fats (fleshings grease) from hides that had been treated with pentachlorophenol were tested in feeding studies and analyzed by electron capture GLC and GLC-mass spectrometric methods. Results of these analyses showed that several test samples contained extremely high amounts of chick edema factor.
Collaborative Study of the Quantitative Gas-Liquid Chromatographic Determination of Fusel Oil and Other Components in Whisky
Authors: Kahn J H , Blessinger E T 
Published: February 2020

Abstract
Fifteen chemists participated in a collaborative study for the quantitative pas-liquid chromatographic determination of the individual fusel alcohols and ethyl acetate in whisky. Two levels of congeners represented by 4 coded samples of whisky were analyzed by using t h e proposed method, employing a glycerol-1,2,6-hexanetriol column, and the official AOAC method, 9.063-9.065. Since isobutyl and the atnyl alcohols comprise by far the greatest part of fusel oil, their determination is of major importance to the total fusel oil content . Statistical analyses show that the proposed method is superior to the AOAC method for the determination of these alcohols, whereas the official method is superior for the determination of ethyl acetate and n-propyl alcohol. In general, collaborators employing modern instrumentation preferred the proposed method over the AOAC method. The former method also separates and permits the quantitative measurement of active amyl and isoamyl alcohols. The proposed method has been adopted as official first action as an alternative to 9.063–9.065 for the determination of higher alcohols and ethyl acetate in whisky.
Collaborative Study of a Gas-Liquid Chromatographic Method for the Determination of Methanol in Alcoholic Beverages
Authors: Dyer R H 
Published: February 2020

Abstract
A collaborative study to determine methanol in alcoholic beverages, using the gas-liquid chromatographic conditions described in the AOAC method for the determination of higher alcohols, 9.063, was carried out. The results showed good recovery values for spiked samples and acceptable standard deviation values, and, according to the ranking test, all collaborators were within the allowable score limits . The advantage of using this chromatographic system for methanol is discussed. The method has been adopted as official first action for the determination of methanol in alcoholic beverages asan alternative to 9.071–9.074.
Efficacy of Various Organic Solvents for the Rapid Direct Determination of Moisture in Meat and Meat Products
Authors: Cohen Edward H , Kimmelman Charles P 
Published: February 2020

Abstract
Twenty-seven organic solvents that form azeotropes with water were tested for use in shortening the time required for the determination of moisture in ground meat, processed frankfurters, and uncooked pork sausage mixture. A goal of 15–30 min was sought with a minimum of 95% recovery of the available moisture content in the meats by use of inexpensive “in stock” available equipment that could be used by nontechnical personnel. Azeotropic distillation in a modified 10 ml Bidwell-Sterling moisture receiver, West condenser, 40/50 boiling flask, and matching enclosed heating mantle was used for periods of time up to 30 min. For example, in 2 lots of ground meat after a 30 min distillation time, the following average recoveries (%) were found: toluene 95, octane 97, nonane 100, xylene 99.7, ethylbenzene 99.4, cumene 100.3, 2-ethyl-1-hexanol 97.7, 1-heptanol 99.5, 1-octanol 99.8, 2-octanol 100.1, and butyl ether 98.5. The latter 9 solvents were found to give acceptable recoveries in 15 min. Chlorinated hydrocarbons were also evaluated but are not recommended due to toxicity levels and the need for specialized equipment.
Rapid Semimicro Method for the Determination of Methyl Mercury in Fish Tissue
Authors: Uthe J F , Solomon J , Grift B 
Published: February 2020

Abstract
A fast semimicro method for the determination of methyl mercury in fish tissue is described. The procedure involves extracting the methyl mercury into toluene as methyl mercuric bromide, partitioning the bromide into aqueous ethanol as a thiosulfate complex, and re-extracting into benzene as methyl mercuric iodide. Methyl mercury is quantitated with gas chromatography. The method is sensitive to 0.01 ppm. Recoveries of added methyl mercury were 99% and the presence of methyl mercury in the final extract was shown by thin layer chromatography and gas chromatography of the thin layer spot. A variety of mercurial compounds do not interfere in the analyses. The amounts of both methyl and total mercury found in a variety of tissues of aquatic animals are compared. The presence of a demethylase in seal is suggested by the findings of high levels of nonmethyl mercury. Additional cleanup by column chromatography on Florisil was necessary with certain samples. The gas chromatographic columns were kept operational by the intermittent injection of 3M potassium iodide. Due to column bleed and resulting detector contamination, the use of the easily cleaned concentric tube electron capture detector is recommended.
Gas Chromatographic Determination of Phenolic Compounds in Drug Preparations: Collaborative Study
Authors: Douglas Carol C 
Published: February 2020

Abstract
A gas chromatographic method for the determination of phenol, methyl salicylate, menthol , and camphor in drug preparations was studied collaboratively by 9 laboratories. Mean recoveries were: phenol 98.2, 106.0, a n d 103.6%; methyl salicylate 103.9, 102.0, and 101.9%; menthol 102.9 and 100.9%; and camphor 101.9 and 100.9%. The method has been adopted as official first action for camphor-containing drugs. Additional study will be done to improve recoveries for the other 3 compounds.
Concentration and Estimation of 14 Polycyclic Aromatic Hydrocarbons at Low Levels in High-Protein Foods, Oils, and Fats
Authors: Grimmer Gernot , Hildebrandt Armin 
Published: February 2020

Abstract
Fourteen polycyclic hydrocarbons in (I) meat, poultry, fish, and yeast, and (II) fats and oils have been isolated and determined. To separate group I homogeneously, 2N methanolic KOH is used. In the first step of concentration (methanol-water-cyclohexane partition (4 + 1 + 5)), a 200 g sample is reduced to 0.2 g of polycyclic fraction without any emulsions. The same effective concentration is found for group II without a saponification step by partition in N,N-dimethylformamide-water-cyelohexane (9 + 1 + 10). Further very effective concentration (100:1) of polycyclics results from filtration on Sephadex LH 20 (solvent:sopropanol). After further cleanup by filtration on silica gel (Woelm, 15% water), phenanthrene, anthracene, pyrene, fluoranthene, chrysene, benzo(a)anthracene, benzo(a)pyrene, benzo-(e)pyrene, benzo(k)fluoranthene, perylene, anthanthrene, benzo(g,h,i)perylene, dibenz(a,h)-anthracene, and coronene are separated on an aluminum oxide column (Woelm, 5.4% water) or equivalent. Recoveries ranged from 75 to 92% for all polycyclics down to the 2 ppb level.
Determination of Bismuth in Body Tissues and Fluids After Administration of Controlled Doses
Authors: Hall Robert J , Farber Theodore 
Published: February 2020

Abstract
Controlled amounts of water-soluble and water-insoluble bismuth salts were administered to dogs. Body tissues and fluids were examined for resultant bismuth residues by an acid digestion-atomic absorption procedure. The method was shown to recover bismuth added to body tissues and fluids; the acid digestion released the bismuth residues almost completely. the highest levels of bismuth were found in the kidneys: about 10 ppm bismuth resulted from the administration of the waterinsoluble compound, bismuth subcarbonale, and about 60 ppm from the soluble compound, bismuth ammonium citrate . The levels of bismuth found in the urine were higher than those found in the other body tissues and the blood serum, but were still relatively low. No pathological manifestations were observed after short-term exposure to bismuth.
Gas Chromatographic Determination of Terrachlor in Fertilizers
Authors: Hanks Alan R , Engdahl Barbara S 
Published: February 2020

Abstract
A simple and rapid method is desorihed for the determination of terraehlor in fertilizers. Terrachlor is extracted with chloroform, and aldrin is added as an internal standard. The extract is injected into a gas chromatography and peak height ratios are used for quantitative measurement. Analysis of commercial samples gives good precision while analysis of prepared samples gives recoveries ranging from 99.3 to 100.4%.
Determination of Lead in Fish by Atomic Absorption Spectrophotometry and by Polarography. II. Collaborative Study
Authors: Gajan Raymond J , Larry Damon 
Published: February 2020

Abstract
Nineteen laboratories, using 6 different models of atomic absorption spectrophotometers and 4 different types of polarographs, participated in this collaborative study. The average lead recoveries from 6 paired samples at 1–2, 5–6, and 10–11 ppm levels were 97.7% by polarography and 100.7% by atomic absorption. The average standard deviations were 0.32 and 0.41 ppm, respectively, and the average coefficients of variation were 7.9 and 13.1%, respectively. With collaborators reporting on both methods, the results of the overall method average were 4.3 ppm for polarography and 4.4 ppm for atomic absorption. Since there were no significant differences (p &gt; 0.05) found between the method averages, except at one of the unspiked levels, the 2 methods can be used to confirm each other at levels of 1-11 ppm. The polarographic method has been adopted as official first action for the determination of lead in fish.
Improved Extraction Procedure for Dimetridazole as Applied to Assay of Samples of Animal Origin
Authors: Allen Patricia C 
Published: February 2020

Abstract
A method for extraction of dimetridazole is described which affords high percentage recoveries of the drug from samples of animal origin. Samples are homogenized with benzene in the presence of just enough aqueous base to insure conversion of all the drug to the free base form and yet obtain a single phase liquid extract. Polarographic analyses of samples spiked with 267 and 33.3 ppm drug showed average recoveries, respectively, of 88.2% (range, 70.5–99.2%) and 87.8% (range, 78.6–101%). The average coefficient of variation for detection of these levels of drug was 3.33%. Under assay conditions, 1 ppm dimetridazole in tissues could not be detected. Factors affecting extent of drug extraction are discussed.
Identities of Polychlorinated Biphenyl Isomers in Aroclors
Authors: Webb Ronald G , Mccall Ann C 
Published: February 2020

Abstract
Twenty-seven PCB isomers in Aroclors 1221, 1242, and 1254 were separated and identified by matching both their GLC retention times and infrared spectra with known compounds prepared by the Gomberg or Ullmann reactions. The retention times of the PCB are presented relative to p,ṕ-DDE.
Liquid Chromatography of Polycyclic Aromatic Hydrocarbons
Authors: Ives N Fred , Giuffrida L 
Published: February 2020

Abstract
The liquid chromatography of 18 polycyclic aromatic hydrocarbons was investigated by using a continuous monitoring ultraviolet detection system. Two column materials, Durapak OPN and 40% cellulose acetate, were compared for orders of elution and resolution. Neither system resolves all the compounds tested but the use of more than one system increases the number which may be resolved. This investigation demonstrates the potential of analytical liquid chromatography for the resolution and analysis of such compounds.
Detection of Hexachlorobenzene Residues in Dairy Products, Meat Fat, and Eggs
Authors: Smyth Robert J 
Published: February 2020

Abstract
A rapid, one column chromatographic method using deactivated Florisil for the cleanup of fatty foods is described. Hexachlorobenzene which is only partially recovered by multiple residue methods is recovered in excess of 80%, using the method described. A gas chromatographic column containing a mixture of DC- 200 and QF-1 as stationary phase for the separation of hexachlorobenzene from a-benzene hexachloride is also described.
Infrared Studies of Cyclohexylamine
Authors: Chen Jo-Yun T , Gould John H 
Published: February 2020

Abstract
The IR spectral data suggest strongly that cyclohexylamine exists as 2 conformers in dynamic equilibrium: an equatorial and an axial form. In the liquid state, under standard conditions, these 2 conformers appear to be present in about equal amounts, but the equilibrium shifts with changes in the physical state of the compound. In the vapor state, the equatorial form is predominant, while in the crystalline solid state at temperatures below – 6°C, only the axial form was observed. This study also shows that the equatorial form is converted to the axial when the sample is subjected to high pressure. The marked chemical reactivity of cyclohexylamine results in its forming a coordinate complex with silver chloride and ammonium salts with CO2 and CS2, all spontaneously at room temperature. The IR spectra of these derivatives of cyclohexylamine are discussed.
Quantitative Determination of Cadmium in Water-Soluble Color Additives by Atomic Absorption Spectroscopy
Authors: Moten Lueangier 
Published: February 2020

Abstract
A quantitative method is presented for the determination of cadmium at low levels (5–20 ppm) in water-soluble color additives by atomic absorption spectroscopy. Absorption measurements were made on aqueous solutions of typical color additives to which known amounts of cadmium had been added. The method requires no pretreatment of sample and should be applicable to all water-soluble color additives.
Gas-Liquid Chromatographic Determination of d-trans-Allethrin
Authors: Meinen Vernon J 
Published: February 2020

Abstract
A gas chromatographic method is described for the quantitative determination of d-trans-allethrin in the technical product and in various formulations. The samples are diluted with acetone and analyzed by gas chromatography, using a flame ionization detector and a column packed with OV-1 on Chromosorb W (HP). Preliminary work indicates that satisfactory results can be obtained with the technical material and several different formulations. Since this method is more rapid and specific than the present AOAC titrimetric method, it is expected that it will be a valuable supplement to or alternative for the AOAC method for the analysis of allethrin.
Nonaqueous Copper Colorimetric Method for Determination of Malathion in Technical Grade Malathion and in Malathion Formulations
Authors: Wayne R S , Ghoth W C , Miles James W , Guerrant Gordon O 
Published: February 2020

Abstract
A nonaqueous copper colorimetric procedure has been developed for the assay of technical and formulated products of malathion. The stability of the copper O,O-dimethyl phosphorodithioate complex has been substantially improved by the use of nonpolar solvents and by lowering the hydrogen ion activity of the system. This has permitted the elimination of the partitioning step and has relaxed the critical timing requirements specified in the offi cial first action AOAC method. The new method has a precision of ±1.6% at a 95% confidence level. The accuracy of the technique is discussed in terms of various minor interferences and by contrasting the results obtained with alternative assay methods.
AG Chlordane: Development of Methods for Its Analysis and Control
Authors: Malina M , Rozek A , Schwemmer B 
Published: February 2020

Abstract
AG chlordane is a high purity compound containing 95% α- and γ-chlordane. Five methods have been developed for analyzing AG chlordane and its formulations. Two methods involve infrared procedures: assay of AG chlordane in granular formulations and α- and γ-chlordane in AG chlordane. The other 3 methods used gas chromatography as the determinative step: assay of heptachlor and nonachlor in AG chlordane and AG chlordane in emulsifiable concentrates. The precisions obtained for all 5 methods are good.