bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thin Layer Chromatographic Determination of Ehtyl 0,0-Dimethyldithiophosphoryl-1-phenyl Acetate in Both Technical Cidial and Its 50% Liquid Formulation
Authors: Bazzi B , Santi R , Radice M , Fabbrini R 
Published: February 2020

Abstract
A method based on the phosphorus determination, including thin layer chromatographic separation, has been developed for determining ethyl 0,0,-dimethyldithiophosphoryl- 1 -phenyl acetate in both technical products and its 50% liquid formulation. The insecticide or a convenient amount of an insecticidal preparation is dissolved in benzene, and the solution is spotted on a thin layer chromatographic plate. After development and spraying with the chromogenic reagent, the surface containing Cidial is detached and eluted. The quantity of the active ingredient in the eluate is obtained by estimation of phosphorus as ammonium phosphomolybdate. The concentration of Cidial in the original sample can be derived by calculation.
Determination of Microgram Quantities of Atropine Sulfate and Hyoscyamine in the Presence of Methylene Blue
Authors: Woodson Albert L 
Published: February 2020

Abstract
Tablets with microgram quantities of atropine sulfate and hyoscyamine, containing approximately 90 times as much methylene blue as total alkaloids, may be assayed successfully. The total alkaloids are separated from methylene blue by partition chromatography. The isolated alkaloids are determined by nitrating, reducing to the aromatic amine, diazotizing the amine, and coupling with the Bratton-Marshall reagent to form a stable red solution. Five assays of a commercial tablet gave values that averaged 96.4% of the label declaration. Recoveries at a level of 37–112 μg/tablet averaged 109%.
A Sweep Co-distillation Cleanup Method for Organophosphate Pesticides.
Authors: Storherr R W , Watts R R 
Published: February 2020

Abstract
A simple sweep co-distillation method which uses the Storherr tube was developed for cleanup of 2 g or less of crude crop extracts which contain organophosphate pesticide residues. Five crops (kale, carrots, apples, strawberries, and potatoes) were fortified at levels of 1.0, 0.5, and 0.1 ppm with a mixture containing Trithion, diazinon, malathion, methyl parathion, and parathion. The sweep co-distillation method was compared with the adsorption column method by use of this mixture. The range of average per cent recoveries were 89–101% and 83–96%, respectively. The cleanup required approximately 20 minutes per sample and was as good as, and in many cases better than, adsorption column chromatography. Detection of the organophosphate pesticides was performed by GLC with the thermionic detector.
Analysis of Dicamba in Crops and Milk, Including a Rapid Cleanup Method
Authors: Smith M , Suzuki H , Malina M 
Published: February 2020

Abstract
A fast, sensitive, and specific method has been developed for determining residues of 2-methoxy-3,6-dichlorobenzoic acid (Dicamba, Banvel-D*) in agricultural crops. Interferences affecting electron capture gas chromatography detection are removed by column partition chromatography. This method has been tested on a wide variety of crops; its sensitivity is 0.05 ppm.
Detection and Estimation of Animal Fats in Vegetable Oils by Gas Chromatography
Authors: Ettinger Charles L , Malanoski Anthony J , Kirschenbaum Herbert 
Published: February 2020

Abstract
The total unsaponifiable matter of various mixtures of animal fat in vegetable oils was extracted with ether following saponification, and this ether extract was subjected to gas chromatographic analysis. The presence of adulterating animal fats was confirmed by chromatography of their sterol acetates on the same column under the same conditions. The presence of 2.5% animal fats in vegetable oils can be detected, and recoveries range from 83 to 116%.
Authentic Vanilla Extracts: Comparison of Analyses of Commercial Samples with Their Laboratory-Prepared Analogs
Authors: Blomquist V H , Kovach E I , Johnson A R 
Published: February 2020

Abstract
Analytical indexes and profiles for 13 commercial and laboratory-made vanilla extracts were compared in a collaborative study. Experimental data are presented and discussed, indicating limits of comparability for the two types of extracts. Agreement in analytical values for corresponding commercial and laboratory-prepared extracts was satisfactory.
Modification of the USP Chemical Method for Determining Vitamin D in Evaporated Milk
Authors: Jones S W , Wilkie J B , Libby D A 
Published: February 2020

Abstract
The USP XVI chemical method for vitamin D in USP products has been substantially modified and applied to evaporated milk containing approximately 30 units of vitamin D per fluid ounce. A major modification is a 15 second reading at 500 mμ which most nearly represents the vitamin D content of the sample. An improved sample preparation eliminates much of the background interference, which also produces a color reaction. This method, when applied to a variety of samples, will show a relative standard deviation of 10%. Statistical data are presented to compare the modified method with the rat bioassay method for assaying vitamin D in evaporated milk.
Collaborative Study of the Infrared Method for DDVP in Pesticide Formulations
Authors: Mitchell L E , O’dowd A C , Patterson D R 
Published: February 2020

Abstract
A collaborative study, begun in 1963, to evaluate an infrared method for determining the DDVP content of four commercially available formulations, was continvied in 1964. Formulations assayed in 1964 were as follows: 0.5% sugar bait, 4 lb/gallon emulsible concentrate, 0.5% spray solution, and 1.0% cattle spray. Special emphasis was placed on refining the procedure applicable to the low-concentration hydrocarbon solutions. A statistical analysis of the data indicates that results of the test program were satisfactory, and the method is recommended for adoption as official, first action.
Collaborative Study of Spectrophotometric Determination of Hexachlorocyclopentadiene in Technical Chlordane
Authors: Malina Marshall 
Published: February 2020

Abstract
Hexachlorocyclopentadiene exhibits strong ultraviolet absorption at 324 mμ, while technical chlordane exhibits only small absorption at this wavelength. The intensity of this absorption is a quantitative measure of the hexachlorocyclopentadiene content. Eight laboratories cooperated in a collaborative study of two alternative procedures on six samples. Results show that one procedure exhibits a positive bias and that the other procedure does not. The precision of both procedures is excellent. The methods are recommended for adoption as official, first action.
Microbiological Methods for Examination of Frozen and/or Prepared Foods
Authors: Surkiewicz Bernard F 
Published: February 2020

Abstract
A method for the microbiological examination of frozen and/or prepared foods as an index to the sanitary conditions under which the food was produced and/or stored was subjected to collaborative study. The method encompasses four determinations: aerobic plate count, the MPN (most probable number) of coliforms, the MPN of E. coli, and the numbers of S. aureus. Subdivisions of custard pie filling, some inoculated with E. coli, A. aerogenes, or S. aureus, were examined by four laboratories. Statistical evaluation of the results indicated that the method gives essentially equivalent results from laboratory to laboratory. It is recommended that the method be adopted as official, first action.
EDTA Titration of Calcium and Magnesium
Authors: Steagall Edward F 
Published: February 2020

Abstract
A revised method for the EDTA titration of calcium and/or magnesium in pharmaceutical preparations was resubmitted for collaborative study this year. The method was also adapted for calcium analysis in tomato products as a check for standards compliance. Three simulated pharmaceutical mixtures and a sample of tomato juice were analyzed collaboratively by 10 analysts in 9 laboratories. The results were easily reproducible, and agreement between laboratories was good. It also appears that the problems of turbidity and fading end points have been resolved. The revised method was recommended for adoption as official, first action.
Raceophenidol in Feed
Authors: Pratt Edward L , Auerbach Morris E 
Published: February 2020

Abstract
Raceophenidol in feed can be estimated by an ultraviolet spectrophotometric measurement of the derived p-methylsulfonylbenzaldehyde. The method, effective for measurement of raceophenidol in feed at medication levels greater than 0.002%, is based on amide hydrolysis and subsequent periodate oxidation. Collaborative studies were conducted on the method; average value was 98.5 ± 7.8%. The method is recommended for adoption as official, first action.
Microcoulometric Gas Chromatographic Determination of Trichloroacetic Acid (TCA) Residues in Wheat Grain
Authors: Chiba M , Morley H V 
Published: February 2020

Abstract
TCA residues in wheat grain may be determined directly without extraction or cleanup. The chloroform formed by decomposition of TCA is collected in xylene and determined by microcoulometric gas chromatography. Two varieties of wheat grown in two different soil types and treated with TCA applied at the 1–4 lb per acre level were analyzed by this direct technique. By using the direct procedure as an arbitrary standard for 100% recovery, comparisons were made among three extraction techniques. Extraction of spiked wheat samples gave recoveries comparable to the direct method. Field-treated samples, however, gave poor recoveries. The results indicated that TCA is not readily extracted from fieldtreated samples, possibly because of combination with basic cell constituents.
Quantitative Determination of Benzaldehyde in Flavors and Cordials by Ultraviolet Spectrophotometry, 2,4-Dinitrophenylhydrazine Precipitation, and the Official AOAC Procedure
Authors: Brunelle Richard L 
Published: February 2020

Abstract
The present official AOAC method was compared with other gravimetric and spectrophotometric procedures for the determination of benzaldelvyde in flavors, cordials, and other distilled spirits products. Collaborative results indicate that the ultraviolet spectrophotometric and the 2,4-dinitrophenylhydrazine gravimetric methods are superior to the present official AOAC procedure, and it is recommended that both be adopted as official, first action as alternative methods.
Nonnutritive Residues: A System of Analysis for the Replacement of Crude Fiber
Authors: Van Soest P J 
Published: February 2020

Abstract
A literature review of the use of crude fiber for the estimation of the poorly digestible part of feedstuffs, together with a discussion of the factors that affect nutritive availability of different chemical entities in feeds, shows that crude fiber may be unsuitable for the evaluation of feeds. The new system described, utilizing detergents, divides dry matter of feeds along lines consistent with modern views in nutrition and emphasizes the cell-wall and lignin contents in feeding materials of plant origin and the acid-detergent insoluble fraction in high protein feeds of plant and animal origin.
Analysis by Microcoulometric Gas Chromatography
Authors: Burchfield H P , Wheeler R J 
Published: February 2020

Abstract
Microcoulometry provides an absolute and stoichiometric measure of chlorine, sulfur, and phosphorus in pesticides. The practical limit of detection of most pesticides containing these ions is 0.01–0.1 µg with the Dohrmann Model C-100; with the Model C-200, 0.001 µg chlorine can be detected. When the coulometer is used in the reducing mode, phosphorus is detected as PH3; when it is used in the oxidizing mode, chlorine is detected as HC1, and sulfur is detected as SO2. Temperature-compatible polar and nonpolar columns can be housed in the same oven, so that relative retention times, as well as elemental compositions, can be crosschecked by using either the oxidation or reduction modes.
Microcoulometric detection eliminates interfering peaks; reduces enhanced baselines; minimizes tailing from the solvent peak; allows programming without column bleed; and permits use of more volatile and less stable liquid phases than is possible with ionization detectors.
Ethoxyquin (Santonin®) in Eggs, Chicken Muscle, and Chicken Liver
Authors: Vanderen John M , Jaworski E G 
Published: February 2020

Abstract
A method, based on the fluorescence of ethoxyquin in iso-octane following a purification procedure, has been developed for the determination of ethoxyquin in egg yolk, chicken muscle, and chicken liver. Ethoxyquin is extracted from tissue with iso-octane and then transferred to dilute sulfuric acid by extraction. The acid is neutralized with sodium hydroxide, and the ethoxyquin is re-extracted by iso-octane. The fluorescence of this solution is then measured. This method gave recoveries of ethoxyquin from egg yolks, muscle, and liver ranging from 60 to 90%, depending upon the tissue and ethoxyquin concentration. The precision of the method is good, with an average standard deviation of 0.04 ppm for samples containing 0.50–2.50 ppm ethoxyquin.
Sulfur Dioxide Determination by Modified Monier-Williams Method
Authors: Thrasher Joel J 
Published: February 2020

Abstract
An alternative trapping system for the two U-tubes now incorporated in the modified Monier-Williams method for total sulfurous acid, 27.079, is recommended. This system is easy to use, permits the titration of distilled SO2 during the determination, and is cheaper and more durable than the U-tube system. The nonapplicability of 27.079 to dried onions, leeks, and cabbage is also discussed.
Halogenated Hydrocarbons in Drugs: Chlorobutanol
Authors: Healton Donald C , Davidson Arthur W 
Published: February 2020

Abstract
An infrared spectrophotometric and gasliquid chromatographic method for chlorobutanol in drugs was studied collaboratively. The method consists of carbon disulfide elution of a Celite column and determination by infrared and/or GLC Recoveries for solutions containing 0.475% chlorobutanol were 91.1 ± 3.6 and 92.2 ± 4.5 for infrared and GLC methods, respectively. Recoveries for solutions containing 0.237% chlorobutanol were 91.0 ± 3.7 and 95.0 ± 4.9 for infrared and GLC methods, respectively. Collaborative results revealed the need for modification of preparation of the standard solution.
The Mass Spectra of Some Organophosphorus Pesticide Compounds
Authors: Damico Joseph N 
Published: February 2020

Abstract
The mass spectra of 23 pentavalent organophosphorus pesticide esters were investigated. Rearrangements and fragmentation by simple cleavage are postulated from analogy with similar compounds, from the presence of chlorine atoms with their readily-recognizable isotopic distribution when applicable, from elemental compositions determined by accurate mass measurements, and, in a few cases, from model compounds. The compounds are divided into four groups: phosphorodithioates, phosphorothionates, phosphorothiolates, and phosphates. The base peaks are formed by rearrangements and simple cleavage. Rearrangement ions are formed by (I) hydrogen migration from the alkyl ester group to the thiophosphite-oxygen skeleton; (2) migration of hydrogen from the Z moiety (aryl or alkyl group) to the phosphorus-oxygen skeleton; (3) migration of hydrogen from the Z moiety to the thiophosphite-oxygen skeleton; (4) migration of hydrogen from the ester group bonded to phosphorus to the Z moiety; and (5) alkyl migration to the Z moiety. The base peak does not characterize the different groups or compounds within a group. However, beta-cleavage (relative to the Z moiety) producing relatively intense peaks (with the charge on the Z moiety) is characteristic of a given group. These data may be useful in identifying metabolites isolated from crops field sprayed with an individual parent organophosphorus pesticide.
Separation of Acetylcodeine from Illicit Heroin by Thin Layer Chromatography
Authors: Nakamura George R 
Published: February 2020

Abstract
The presence of acetylcodeine as an impurity in illicit heroin preparations has been demonstrated by the detection of codeine in hydrolyzed samples. The method described here, using thin layer chromatography, showed that acetylcodeine per se can be separated from illicit heroin and that it can be used as a basis for screening such illicit preparations for acetylcodeine.
Ultraviolet Determination of 2-Pivalyl-l,3-indandione (Pival) and Its Sodium Salt in Rodenticide Formulations
Authors: Griffin Travis B , Blazek Nancy A 
Published: February 2020

Abstract
An ultraviolet spectrophotometric method for 2-pivalyl-l,3-indandione in finished rodenticide baits involves extraction of the bait with a glycine-sodium hydroxide buffer, acidification with trichloroacetic acid, and extraction into cyclohexane with 0.5JV sodium hydroxide. Interfering substances were removed by chloroform. The absorbances were measured at 283 and 319 mμ in an ultraviolet spectrophotometer, and the rodenticide content was calculated by a modified base point technique. Quantitative recoveries were obtained when model baits were analyzed.
Laboratory Variations in the Analysis of Fertilizers
Authors: Quackenbush F W , Rund R C , Miles S R 
Published: February 2020

Abstract
Five carefully prepared mixtures of fertilizer-grade chemicals were analyzed by 23 laboratories under routine circumstances in which the laboratory personnel were unaware that they were participating in a research study. The experiments were designed to observe variations within and among laboratories when heterogeneous samples were reduced and analyzed according to the usual laboratory routine: first, as compliant samples (meeting a guarantee); and second, as deficient samples (below a guarantee). The individual analyses in the study totaled 2,242. In addition to the data on variation within and among laboratories, the observations provided information on bias, both in the analysis and in the reporting of results by the administrator of the laboratory.
Two-Dimensional Thin Layer Chromatographic Procedure for the Identification of Dye Intermediates in Arylamine Oxidation Hair Dyes
Authors: Kottemann Christine M 
Published: February 2020

Abstract
Dye intermediates in arylamine oxidation hair dyes are identified by a two-dimensional thin layer chromatographic method. An initial development in basic solution is followed by development in an acidic solution. The dye intermediates are identified by their color reactions with spray reagents and by their spatial relationships to known intermediates developed on the same plate. The chromatographic study included 30 dye intermediates proposed for use in commercial oxidation-type hair dyes.
Routine Determination of Carbaryl in Dipping Fluids and Deposits on Cattle Hair
Authors: Dingle J H P 
Published: February 2020

Abstract
Sampling techniques and an ultraviolet method, capable of handling large numbers of samples, have been developed for carbaryl in dipping fluids and cattle hair deposits. The absorbance (280 mμ) of dip samples is measured after suitable dilution with ethanol; a correction is made for the presence of 1-naphthol, but background interference from dip dirt, clay, cow dung, etc. is negligible at the dilutions used. The amount of carbaryl deposited on cattle hair dipping is estimated similarly after extraction with ethanol. The accuracy of the dip analysis and the effect of hair grease on the analysis of hair deposits are discussed.
A Versatile Procedure for Assay and Preparatory Separation of Aflatoxins from Peanut Products
Authors: Eppley Robert M 
Published: February 2020

Abstract
A procedure in which the direct extraction of a water-wetted sample by chloroform is combined with the use of a silica gel column for defatting and cleanup has been devised for obtaining clean quantitative extracts of aflatoxins from 50 g and 1 kg peanut product samples. The method is rapid; the manipulations are easy and uninvolved. The low level of interference permits the detection and estimation of as little as 1 μg aflatoxins/kg of peanut product sample.
Comparison of Potassium Content of Fertilizers by Atomic Absorption and Sodium Tetraphenylboron
Authors: Mccrackan M L , Webb H J , Hammar H E , Loadholt C B 
Published: February 2020

Abstract
Atomic absorption spectrophotometry is a rapid and simple screening method for determining potassium in fertilizers, especially when a large number of samples are processed. The potassium content of 1190 fertilizer samples was determined by both atomic absorption (4038Å) at a dilution of 1:400 and by the sodium tetraphenylboron method; correlation between the two methods was significant (r = 0.96). Triplicate analyses of 101 samples by each method showed precision of 0.229% by STPB and 0.424% by atomic absorption; standard deviation of the difference between the two procedures was 0.50%. Other elements normally found in fertilizers did not interfere at 4038Å.
Ultraviolet Spectrophotometric and Gas Chromatographic
Methods for Ronnel in Feeds
Authors: Gehrt Albert J 
Published: February 2020

Abstract
Two new methods for ronnel in feeds at levels of 0.035-0.60% ronnel were developed and studied by 10 collaborators. Methods involve extraction of the sample (with chloroform for ultraviolet measurement or with acetone for gas chromatographic measurement) followed by Florisil cleanup of the extracts. Both methods measure true ronnel. The described methods are simpler and give better ronnel recoveries (92— 105%) than the present official, first action steam distillation method. Agreement between laboratories was good; coefficients of variation were 4.1—11.1%. Several collaborators encountered difficulty with Florisil cleanup at the low level (0.03% ronnel). It is recommended that study be continued on the standardization of Florisil
Collaborative Study of Capillary Viscometer Method for
Consistency of Fruit Nectars and Fruit Juice Products
Authors: Lamb Frank C 
Published: February 2020

Abstract
Collaborative results were obtained from 12 analysts from 9 laboratories, using the capillary viscometer on samples of apricot, peach, and papaya nectars and on pineapple- grapefruit and pineapple-pear fruit juice drinks. Each analyst reported triplicate results on 2 individual canned samples of each product. With the exception of one analyst, satisfactory agreement was obtained on all of the samples. Standard deviations varied from 2 to 4.6% of the actual readings. Variability was least for samples of apricot and peach nectar and the pineapplegrapefruit drink and greatest for the papaya nectar, probably due to can-to-can variation. The capillary viscometer method is accurate for measuring the consistency of fruit nectars and other fruit juice products, The method was recommended for adoption as official, first action
Paper Chromatographic Detection of Adulteration in Concord
Grape Juice
Authors: Fitelson J 
Published: February 2020

Abstract
Paper chromatography of the anthocyanidins, the phenolic components of the anthocyanins, is the most satisfactory means of detecting adulteration of Concord grape juice with other red grape juice and colored Italian grape skin extract. The 5 aniliocyanidins found in grape colors can be readily separated into 3 spots by paper chromatography. In the proposed method, anthocyanins are separated by lead precipitation, dissolved in water, and acid-hydrolyzed to obtain the anthocyanidins. Thirty Concord samples, 7 red grape juice samples, and 5 Italian grape skin extracts were examined and results were good. Four unknown samples were analyzed by 5 collaborators; all collaborators correctly detected the adulterated sample and the pure Concord sample. This method was recommended for adoption as official, first action