bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Critical Evaluation of the Reduced-Iron Method for Reduction of Nitrates
Authors: Brabson J A , Burch W G , Woodis T C 
Published: February 2020

Abstract
The first action reduced iron method for nitrogen in fertilizers specifies the use of electrolytic iron and indicates that a large excess of iron is required for the reduction of nitrates. Iron reduced by hydrogen, however, is a more efficient reductant than electrolytic iron, but it requires a longer reaction time. The specified amount of iron is excessive. The particle size of the iron is important, and 250-mesh is the largest particle size that should be used; specification of the average particle diameter in microns is recommended. The reduced iron method is, at best, a cumbersome procedure, and other, more efficient, reductants for nitrate should be sought.
Collaborative Study of Determination of Silicon in Agricultural Liming Materials
Authors: Chichilo P 
Published: February 2020

Abstract
Six samples of liming materials, including carbonates and silicates, were analyzed for silicon content by: (I) The AOAC method; (II) the AOAC method plus volatilization of SiO2 with HF; (III) the AOAC method, omitting the Na2CO3 fusion of the sample, including the HClO4 dehydration of SiO2, plus HF volatilization of SiO2; and (IV) a colorimetric method. Nine collaborators reported results by Methods I, II, and III and eleven by Method IV. Precision of the methods was good; no method was superior for all samples. Method I gave high results for most samples; the average result with Method I for a standard sample of dolomite was high, but that for a standard limestone was near the certificate value. Average results by Methods II, III, and IV for the standard samples were near certificate values. The collaborators appeared to prefer Method IV.
Rapid Screening Procedure for Benzoates in Meat
Authors: Stanley Ronald L 
Published: February 2020

Abstract
A rapid screening procedure is being developed for the detection and determination of benzoates in meat. In the current stage of the method, the meat sample is digested in a mixture of perchloric and acetic acids, and the fat is determined in a Paley cheese bottle. The benzoic acid is then extracted with ether, and the benzoate is identified and estimated by its ultraviolet spectrum. The method gives accurate quantitative results when the benzoate concentrations in the meat exceed 500 ppm, and semi-quantitative results in the range 100—500 ppm. It is recommended that the method be studied collaboratively.
Determination of Dihydrocodeinone in Mixtures With Antihistamines
Authors: Levine Joseph 
Published: February 2020

Abstract
Dihydrocodeinone is separated from pheniramine and similar antihistamines by passage of a chloroform extract of the combined bases over a chromatographic column on which 2N HCl is the stationary phase. The latter is retained on the column while the dihydrocodeinone passes through. The dihydrocodeinone is transferred from the chloroform eluate by shaking it with a measured volume of sulfuric acid, and the concentration is measured spectrophotometrically. The method is recommended for adoption as official, first action.
Recent Research Concerning the Freezing Point Value of Milk Produced in the Southeastern United States
Authors: Henningson R W 
Published: February 2020

Abstract
In 1953 Dahlberg, et al. published the first information indicating that the freezing point value of milk produced in the Southeastern United States might be higher than commonly accepted values. An extensive survey of retail milk marketed in South Carolina during 1957 produced an unweighted average freezing point value of –0.529°C, and disclosed that the unweighted average milk solids-not-fat content of retail milk marketed in South Carolina was 8.88%. Other surveys revealed such freezing point values as –0.537, –0.540, –-0.533, –0.528, and –0.532°C. Custer and Cardwell found freezing point depressions averaging 0.025—0.030°C less for reconstituted non-fat milks of southern origin than for similar milks of northern origin. The lactose and chloride contents of these milks were lower than those of the northern milks. Problems created by high freezing point values which are intensified by the effects of vacuum pasteurization, common in the Southeastern United States, on freezing point values will be discussed.
Composition Studies on Tobacco. XVI. Steam-Volatile Acids
Authors: Schmeltz Irwin , Stedman R L , Miller R L 
Published: February 2020

Abstract
The lower fatty acids of various types and grades of tobacco were studied by gas chromatography and identified by chromatographic and infrared spectral characteristics. Acids from C1 or C2 to C9 were found, including four (n-C4, n-C7, n-C8, and n-C9) not previously reported in tobacco leaf. Among the tobaccos investigated were bright (aromatic and aroma-deficient grades), burley, Maryland, and Turkish (Smyrna and Samsun). In general, all samples were qualitatively similar in volatile acid composition. Quantitatively the tobacco types differed as follows: Turkish (Samsun) contained a much higher level of β-methylvaleric acid (greater than four times) and a lower level of combined acetic and formic acids (less than one-half) than bright, and had a much higher proportion of isovaleric to n-valeric acid. Burley and Maryland contained lower levels of all identified acids than Turkish (Samsun) and bright. Among the grades of bright, the aromatic tobaccos contained more volatile acidic material than the aromadeficient tobaccos, and showed other differences in distributions of lower fatty acids compared to aroma-deficient samples.
Mycotoxins. I. Studies on Aflatoxin Derived from Contaminated Peanut Meal and Certain Strains of Aspergillus flavus
Authors: Armbrecht Bernard H , Hodges F Allen , Smith Howard R , Nelson Arthur A 
Published: February 2020

Abstract
Aspergillus flavus strains were obtained from British and domestic sources, and were cultured in our laboratories. Aflatoxin, the toxic derivative, was extracted from peanut meal by the method of Sargeant, et al. and from wheat by our method. The amounts of toxic substances present were estimated by paper chromatography. Concentrates were obtained by precipitation. One concentrate was reduced. Toxicity tests on ducklings confirmed British findings.
Use of Detergents in the Analysis of Fibrous Feeds. I. Preparation of Fiber Residues of Low Nitrogen Content
Authors: Soest P J Vax 
Published: February 2020

Abstract
Anionic, cationic, and nonionic detergents in different buffering media were examined for their capacity to dissolve nitrogenous constituents in forage dry matter, in the interest of preparing fiber of a low nitrogen content. Of the combinations examined, cetyl trimethyl ammonium bromide in strongly acid solution and sodium lauryl sulfate in slightly alkaline solutions appeared most effective.
Pesticide Residues in Commercial Animal Feeds
Authors: Minyard J P , Jackson E R 
Published: February 2020

Abstract
One hundred and one commercial feeds, of which 87 were dairy feeds or supplements, were analyzed for chlorinated organic pesticide residues by gas chromatography utilizing 5% SE-30 for the stationary phase and electron capture detection. A computation scheme for determining γ-BHC, aldrin, dieldrin, endrin, DDD, DDT, methoxychlor, heptachlor, heptachlor epoxide, chlordane, and toxaphene in combination with each other was developed, and values were tabulated for each in each feed. Contaminations ranged from low tens to hundreds (ppb). Most of the feeds contained residue amounts below those which would be expected to produce detectable residues in milk. Higher contamination levels were tentatively correlated with specific feed ingredients, as well as with protein and crude fiber content. Higher contaminations were observed with higher fiber content, lower feed protein value, and when grain screenings, rice bran, or rice mill by-product were ingredients. Much lower contaminations were associated with ground milo, wheat bran and middlings, ground and crimped oats, linseed oil meal, and various corn products.
Preparation of Electron Capturing Derivatives of Insensitive Pesticides
Authors: Gutenmann Walter H , Lisk Donald J 
Published: February 2020

Abstract
Many agricultural chemicals do not possess the proper structure or a sufficient number of electronegative functional groups for electron affinity determination. In the work reported, bromination coupled with other reactions is used to prepare sensitive derivatives of diphenyl, Guthion, MCP, and MCPB. Electron affinity gas chromatograms and standard curves representing nanogram quantities of these agricultural chemicals are illustrated.
Use of Starch-Gel Electrophoresis to Illustrate Inhibition of Tissue Esterases by Organophosphorus Pesticides. II. Comparison of Homogenates of Different Origin
Authors: Read Sheila I , Mckixley W P 
Published: February 2020

Abstract
Comparison of starch-gel electrophoresis patterns of ali-esterases of rabbit spleen, lung, brain, heart, and kidney showed that liver contained the most esterase, kidney the next greatest amount; patterns were generally similar, although amounts of esterase differed in different parts of the gel. Similar studies on various species of mammals, fowl, and fish showed that, in general, patterns of the same organ differed among species. Various enzymes appeared to be somewhat specific with respect to inhibitors but not to substrates, under the conditions used. Bromine treatment increased the inhibitory effect of Schradan, Dibrom and Ruelene, and EPN and parathion, in decreasing order.
Determination of Mercury in Pink Wheat
Authors: Jones Lawrence , Schwartzman George 
Published: February 2020

Abstract
A dithizone method for determining Hg in pink wheat, in which the sample size is limited to 250 mg, has been designed to measure 0—20 μg of μg, although larger amounts can probably be measured by adjusting conditions. In the 1.0—2.0 μg range of Hg, the recovery is about 14% low. An analysis may be completed in 2 hours after the initial kernel has been picked out under ultraviolet light.
Cleanup for Residue Analysis of Some 2,4-D Esters in Potatoes
Authors: Bevexue Arthur , Zweig Gunter , Nash Nancy L 
Published: February 2020

Abstract
A cleanup procedure was devised for analysis of 2,4-D esters in potatoes which eliminated the interference of a halogen-containing material in the potatoes. Recoveries on fortified samples were 82-84%.
Thin-Layer Chromatography for Chlorinated Pesticide Residue Analysis
Authors: Kovacs Martin F 
Published: February 2020

Abstract
A rapid sensitive method for the application of thin-layer chromatography to the detection and estimation of chlorinated organic pesticide residues has been developed. Compared to paper chromatography the method is faster, more sensitive, and in most cases more specific. Chlorinated pesticide residues were identified in extracts of various food products at concentrations as low as 1 part per billion; these results were verified by gas-liquid chromatography.
Because of its simplicity, speed, and sensitivity, thin-layer chromatography is suitable as a rapid screening method or as a confirmatory method in conjunction with gas-liquid chromatography or other analytical methods for chlorinated pesticide residue analysis.
Adaptation of a Twin-Beam Ultraviolet Spectrophotometer for Spectrophotometric Neutralization Analysis
Authors: Wilkie John B 
Published: February 2020

Abstract
Spectrophotome trie neutralization may be used to evaluate absorbing compounds in the presence of interference. The procedure has been expedited by new apparatus and technique, which eliminate the use of large volumes and pumping. The adaptation does not require extensive machine work, and conversion to ordinary spectrophotometric operation from optical neutralization operation is rapid.
Rapid Method for Determination of Moisture in Freeze-Dehydrated Shrimp
Authors: Despaul John E , Ezerski Donald W 
Published: February 2020

Abstract
Difficulties in determining moisture in freeze-dehydrated shrimp by the toluene distillation method were overcome by drying several whole shrimp directly in a vacuum oven. This procedure is faster and more reliable than several other methods tried, and results of a limited collaborative study show that it compares well with the toluene distillation method.
Determination of Certifiable FD&C Color Additives in Foods and Drugs
Authors: Graichen Charles , Molitor John C 
Published: February 2020

Abstract
Dolinsky and Stein described the use of a liquid anion exchange resin in butanol to extract FD&C colors from baked goods. The experience gained in our laboratory from analysis of over 450 food samples and more than 250 drug and vitamin samples by this procedure led to the development of several modifications of the original method. Solutions of the resin in hexane are employed to separate the azo colors from the triphenylmethane colors. For certain colors, a buffered resin solution is employed to minimize decomposition. The modification of the procedure to be employed depends primarily upon the color or colors present rather than upon the product to be analyzed. The applications of these procedures and their limitations in the analysis of foods and drugs for certifiable colors are discussed.
Determination of Piperazine in Formulations by Nonaqueous Titration
Authors: Maybury R B , Payfer R 
Published: February 2020

Abstract
A new method is presented for the nonaqueous titration of piperazine in formulations in which the piperazine base is first brought into aqueous solution, and the solution is made strongly alkaline and extracted with chloroform. The chloroform solution of piperazine is then titrated with acetous perchloric acid to alpha-naphthol benzein indicator. The procedure is rapid, shows good agreement with other methods, and is applicable to most kinds of piperazine formulations.
An alternative procedure for piperazine adipate, citrate, or tartrate in powders is given, in which the compound is dissolved and titrated directly in glacial acetic acid.
Quantitative Determination of Benzaldehyde in Flavors by Gas-Liquid Chromatography
Authors: Brunelle Richard L , Martin Glenn E 
Published: February 2020

Abstract
A rapid and specific method is given for determination of benzaldehyde in the presence of interfering substances by gas-liquid chromatography. Separation is effected on a ¼ column containing 2 5% Apiezon M as the liquid phase on a solid support of Chromoport XXX (60—80 mesh) at isothermal conditions, 100°C. The determination can be performed in the presence of benzoic acid and other interfering substances. Results are compared with those obtained by ultraviolet spectrophotometry on a variety of almond and cherry flavors.
Resistance of Pseudomonas to Various Chemical Germicides
Authors: Beloian A , Koski T 
Published: February 2020

Abstract
Studies were conducted to determine the range of susceptibility of Pseudomonas to seven samples of commercial contact germicides. Tests were made by the official phenol coefficient method, 5.001-5.009. Ranges of resistance for Pseudomonas strains varied with the germicides tested and the concentration of germicide used. Chlorine in water supply systems showed a resistance range of 45-150 ppm to Pseudomonas organisms. Comparative studies were also conducted, using the dilution test method, on various strains of Pseudomonas to determine the effectiveness of disinfectants; strain PRD-10 proved to be the test strain of choice for determining the validity of Pseudomonicidal claims.
Aflatoxin: Effect on Mitotic Division in Cultured Embryonic Lung Cells
Authors: Legator Marvin S , Withrow Alida 
Published: February 2020

Abstract
Crude aflatoxin mixtures as well as crystallized B1 aflatoxin suppressed mitotic division in heteroploid and diploid human embryonic lung cells. This inhibition occurred 4 hours after exposure of the cells to the toxicant and reached a maximum in 8—12 hours. A concentration of 0.01 μg of the toxicant could be detected by this method. A sample of 2 μg of TLC pure B1 (determined by chemical assay) derived from contaminated peanuts was submitted for assay. A concentration of 0.03 μg produced a 51% reduction in mitosis.
Application of 4-(p-Nitrobenzyl) pyridine as a Rapid Quantitative Reagent for Organophosphate Pesticides
Authors: Getz Melvin E , Watts Randall R 
Published: February 2020

Abstract
A rapid colorimetric determination for organophosphate pesticides is reported. The basis for this method is the reaction between nitrobenzyl pyridine and phosphate pesticide in a slightly basic solution at 175-180°C. The method reported is rapid and has a sensitivity of approximately 2 μg of an organophosphate pesticide. Recoveries are presented for several crops fortified at 1 ppm. Interferences were noted for some types of crops, and the need for further cleanup work was indicated.
The Mass Spectra of Some Carbamate Pesticides
Authors: Damico Joseph N , Benson Walter R 
Published: February 2020

Abstract
The mass spectra of fourteen carbamate pesticides have been tabulated. The carbamates are divided into three classes: N-methyl, N-phenyl, and N,N-dimethyl. The significant fragmentation ions for these three classes are noted, and ions are postulated for the eight N-methylcarbamates rearrangement. The data can be utilized to characterize these classes of compounds.
Extraction and Assay Methods for Sugars in Apples and Carrots
Authors: Eheart James F , Mason Blanche S 
Published: February 2020

Abstract
Results of a statistically planned study are presented which show the extraction effectiveness of four different ethanol concentrations, and also whether it is necessary to reflux, add CaCO3, and use sample replicates, duplicate ethanol extract aliquots, and duplicate colorimeter tubes for the determination of total and reducing sugars, sucrose, glucose, and fructose in fresh apples and carrots. The copper sulfate-arsenomolybdate and the ferric ferricyanide-arsenomolybdate colorimetric methods for the determination of total and redvicing sugars and sucrose were also compared. Based on result obtained from this study, the addition of CaCO3, and refluxing the ethanol extracts, and the use of duplicate aliquots of ethanol extract and duplicate colorimeter tubes were unnecessary; at least two replicate samples should be vised. Differences in the results by assay method (Cu and Fe reduction) were not consistent enough to justify recommending one method over the other for the determination of total and reducing sugars and sucrose. The most effective ethanol concentration for extracting sugars from apples was 85% (v/v); for extraction from carrots, 75% was best.
Quantitative Determination of Blood Added to Hamburger
Authors: Hankin Lester 
Published: February 2020

Abstract
A quantitative method is proposed for determining blood deceptively added to ground beef (hamburger) to conceal excess fat. Blood is eluted from the sample with water, oxidized with hydrogen peroxide to liberate iron from the hemoglobin, and then treated with sodium tungstate to precipitate proteins. Iron content is then measured. Samples of hamburger to which blood was added were analyzed to provide a standard formula for the calculation of excess blood in unknown samples. The amount of iron in unadulterated or blank samples is taken into account in these calculations. Tolerance limits for the method are given.
Methods for Evaluating Vitamin A Isomers
Authors: Ames Stanley R 
Published: February 2020

Abstract
Precise estimation of the biological activity of the vitamin A in various products is complicated if cis isomers are present because they have lower biopotencies than alltrans isomer. Two general types of vitamin A sources contain cis isomers; the trans-neo type contains all-trans and 13-cis isomers, and the trans-cis type (including fish liver oils) contains, in addition, the 9-cis and 9,13-di-cis isomers of very low biopotency. The trans-neo type cannot be satisfactorily assayed by the SbCl3 blue color procedure, but the USP assay gives a satisfactory estimate of biopotency. No colorimetric or spectrophotometric procedure alone can be used to estimate the biopotency of the transcis type. Two empirical equations involving biopotency, maleic value, and either blue color or USP analyses satisfactorily estimate the biopotency of the trans-cis type of vitamin A product.
Extraneous Materials in Mushrooms
Authors: Brown Robert F 
Published: February 2020

Abstract
Studies were continued on the official, first action method for extraction and microscopic examination of maggots in canned mushrooms, 36.085(a). A No. 10 and a No. 16 sieve were added to the nested sieve combination used in the method, and a widefield stereoscopic microscope equipped with an ocular micrometer was used for maggot measurement. Results indicate that changes should be made in method 36.085 (a) to permit analyses of mushroom samples containing larger and various sized maggots
Separation, Determination, and Identification of Antipyrine and Benzocaine in Glycerol and Propylene Glycol Bases
Authors: Krause Richard T 
Published: February 2020

Abstract
Antipyrine and benzocaine are separated by column partition chromatography on three columns arranged serially with the sample-Celite mixture (top), a ferric chloride-Celite mixture (middle), and 22V HCl-Celite mixture (bottom). Antipyrine is retained on the ferric chloride column, and benzocaine is retained on the HC1 column. Maximum absorbances are determined on chloroform eluates at 272 and 283 mμ for antipyrine and benzocaine, respectively. Infrared spectra of the residues are determined in potassium bromide. Recoveries from 6 simulated commercial preparations averaged 100.4 ± 0.4% for antipyrine and 99.2 ± 0.5% for benzocaine. Six commercial products were also analyzed and per cent of declared ranged from 96.0 to 107.0 for antipyrine and from 92.4 to 106.0 for benzocaine. Infrared spectra of sample residues produced spectra with the same absorption peaks as that of the respective standards. It is recommended that additional work be done to verify recoveries of the urea-acetic acid preparation and that the method then be studied collaboratively.
Lysine and Methionine Availability in Heated Casein-Glucose Mixtures
Authors: Rao M Narayana , McLaughlan J M 
Published: February 2020

Abstract
Mixtures of casein, glucose, and water (2:2:1) were autoclaved at 15 p.s.i. for 5, 10, 20, and 40 minutes and then freeze dried. The available lysine and methionine in the casein-glucose (C-G) mixtures were determined by chemical and bioassay techniques. There was a considerable decrease in the amount of available lysine (65—68%) and methionine (39—47%) in the samples antoclaved for 20 and 40 minutes. The gross protein values of C-G mixtures combined with basal diets deficient in lysine or methionine gave values for available lysine and methionine which agreed closely with those obtained by chemical and microbiological assays. Plasma lysine levels correlated well with the gross protein values (r = 0.99; n = 4) and dinitrofluorobenzene available lysine; however, the correlation between the plasma methionine levels and gross protein values was not as significant (r=0.75; n = 5). The results presented here show that it is possible to use plasma amino acid levels as an index of the nutritional availability of certain amino acids in foodstuffs.
The Dumas Method for Nitrogen in Feeds
Authors: Ebeling Melvin E 
Published: February 2020

Abstract
A second collaborative study was made to compare Dumas with Kjeldahl methods for nitrogen determination in agricultural feed materials. The Dumas method used was the Nitrogen Analyzer II, Coleman Model 29A. The two methods were compared by ten participating laboratories on seven feed materials and one organic standard compound. Results for the Dumas procedure were in good agreement with the AOAC Kjeldahl method, and a high order of precision was achieved. It is recommended that the Dumas method be adopted as official, first action.