bluuebunny/crossref_metadata_2025_split huggingface dataset:
Filth in Fruit Paste
Authors: Wheeler Helen H 
Published: February 2020

Abstract
A two-step procedure for examining fig paste for light filth and heavy filth has been investigated. The first step is a modification of method 36.052, using a kerosene-water flotation treatment to separate light filth elements. The second step consists of treating the residual material from flotation with Na4EDTA and screening on a No. 140 sieve to recover heavy filth elements, along with light filth not separated by flotation. Studies indicate that the proposed kerosene- water flotation gives superior recovery of light filth and heavy filth, and the method is recommended for adoption as official, first action.
A Method for the Routine Determination of Corn Sirup in Prepared Meat Products
Authors: Hankin Lester , Wickroski Alphonse F 
Published: February 2020

Abstract
A method has been devised for the determination of corn sirup added to processed meat products. The method is based on the quantitative determination of dextrin added to corn sirup. The dextrins are enzymatically hydrolyzed by α-amylase and β-amylase, and maltose is calculated as the difference in CuO2 found by copper reduction between a treated and an untreated aliquot. A correction factor was devised to determine the average amount of dextrin in corn sirup by testing a number of commercial sirups for their dextrin content and subjecting the data to statistical analysis. With this equation the method is applicable to a wide range of sirups. The method also permits the estimation of dextrose added to meats in excess of that included as one of the components of corn sirup.
An Improved Alkaline Citrate Method for Evaluation of Phosphorus in Fertilizers
Authors: Brabson J A , Burch W G 
Published: February 2020

Abstract
The Netherlands alkaline ammonium citrate extraction method for the determination of available P2O5 was modified for routine use. The water-insoluble portion of the sample is extracted with the alkaline citrate solution for 2 hours in a shaking apparatus at 65°C. Dicalcium phosphate dissolves, but apatite, whether formed in processing (as in the ammoniation of superphosphate) or present as unreacted phosphate rock, does not dissolve. The results of the extraction method correlate well with those of field tests of the fertilizers.
Residues in Milk of Cows Fed Rations Containing Low Concentrations of Five Chlorinated Hydrocarbon Pesticides
Authors: Williams S , Mills P A , Mcdowell R E 
Published: February 2020

Abstract
A feeding study involving 16 lactating dairy cows was carried out in which mixtures of 5 pesticides (heptachlor epoxide, dieldrin, endrin, lindane, and DDT) were fed at levels of approximately 0.05, 0.15, and 0.30 ppm of each pesticide based on total feed consumption. Analyses showed that heptachlor epoxide and dieldrin transferred to the milk in much higher concentrations than did the other pesticides. Next in order of concentration were endrin and lindane. Small but definite increases of DDT and TDE in the milk were noted with increased feeding levels of DDT, but the DDE concentration was apparently not affected by the feeding of DDT at these levels.
Metabolites: Reductive Dechlorination of DDT to DDD and Isomeric Transformation of o,p’-DDT to p,p’-DDT In Vivo
Authors: Klein A K , Laug E P , Datta P R , Watts J O , Chen J T 
Published: February 2020

Abstract
Feeding p,p’-DDT and o,p’-DDT separately at a level of 50 ppm in the diet of rats causes reductive dechlorination of DDT to DDD in the liver. No DDD was found in the fat. DDE is not involved in the metabolic pathway. Feeding o,p’-DDT yields evidence of isomeric conversion to p,p’-DDT in the fat stores. The proportion of the p,p’-DDT found to the o,p’-isomer observed is approximately 7:1.
A Comparison of Assay Procedures for Aflatoxin in Peanut Products
Authors: Tracer W T , Stoloff L , Campbell A D 
Published: February 2020

Abstract
A number of analytical procedures for aflatoxin assays, which were used in the autumn of 1963 by government and industry laboratories, were compared for their efficacy in the detection and quantitative estimation of aflatoxin in peanut meal and peanut butter. All but one of these procedures employed aluminum oxide thin-layer chromatography in the determinative step, but the method employing silica gel thinlayer chromatography was shown to be superior to the aluminum oxide technique. When silica gel was used as the determinative step in each of the procedures, all but one were found to be approximately equal. The other procedure did not effectively extract the aflatoxin.
An Ultraviolet Absorption Criterion For Total Polynuclear Aromatic Hydrocarbon Content of Petroleum Waxes in Food Additive Use
Authors: Howard John W , Haenni Edward O , Joe Frank L 
Published: February 2020

Abstract
An ultraviolet absorption test to limit the total polycyclic aromatic hydrocarbon content in petroleum waxes has been developed. The procedure consists of extraction of a solution of melted wax in an aliphatic solvent with a dimethyl sulfoxide-phosphoric acid mixture, followed, if necessary, by chromatography on a magnesia-Celite column.
Recoveries of representative polycyclic aromatic hydrocarbons, added at a level of 12.5 μg to 25 g samples (0.5 ppm) of wax, ranged from 64 to 93% after the extraction part of the procedure, and from 44 to 85% after the column chromatographic part of the method. The variations in the recoveries may be attributed to the differences in the partition coefficients of the hydrocarbons between the aliphatic solvent and the dimethyl sulfoxide-phosphoric acid extraction mixture, plus the tendency of some of the compounds to be oxidized during the chromatographic part of the test.
The procedure has been applied to the analysis of commercial, refined petroleum waxes, and specifications have been developed to limit the total polycyclic aromatic content of such waxes for food additive use.
Rapid Colorimetric Determination of Microgram Amounts of Selenium in Soils and Biological Samples, Using Millipore Filters
Authors: Newberry Carvel L , Christian Gary D 
Published: February 2020

Abstract
A method is described for the determination of selenium in biological samples or soil samples, following acid digestion or distillation as the tetrabromide, respectively. The selenium is reduced to the element by ascorbic acid. The element is filtered and collected on a white Millipore filter. The intensity of the coloration of the filter is used as a measure of the selenium content. The range of the method is from 0.2 μg selenium to &gt; 0.1 mg selenium. Complete analysis time for a single biological sample is about 60 minutes, while that for a soil sample is less than 2 hours. Control of variables is not critical.
Isolation of Microquantities of Pesticides by Gas Chromatography for Infrared Analysis
Authors: Giuffrida Laura 
Published: February 2020

Abstract
A dual column gas chromatography system using a fraction collector has been developed to isolate one or more components in a mixture for infrared analysis. Interferences from solvents and other contaminants are virtually eliminated because of the separation qualities of the GLC column. Compounds in the vapor state from the GLC column are condensed directly on KBr powder to obtain infrared spectra of microquantities of pesticides.
Separation and Micro Quantitative Determination of Dipterex and DDVP by Gas-Liquid Chromatography
Authors: El-Refai Abdel Rahman (Ali) , Giuffrida Laura 
Published: February 2020

Abstract
A simple, rapid, and sensitive method was required for the determination of Dipterex and DDVP in water and insecticidal formulations. Existing methods were found to he unsatisfactory. This paper describes a rapid method for the gas chromatographic separation and estimation of Dipterex and DDVP in macro and micro amounts. The sodium thermionic detector (STD) was used, and the GLC conditions are described. A general method for extraction of the two compounds from water solutions was developed and applied in studying the rate of hydrolysis of Dipterex and DDVP in river water. A simple procedure has been developed for analysis of formulations of Dipterex and DDVP. Several commercial formulations have been analyzed by this method with a precision of 1–2% obtained under experimental conditions.
Micro KBr Technique of Infrared Spectrophotometry
Authors: Chen Jo-Yun T 
Published: February 2020

Abstract
A combined metal funnel and packing device are used to prepare 4 mg of KBr powder for pressing in a 2 mm diameter hole punched into folded aluminum foil. With the sample added and the KBr pressed between metal blocks a clear transparent disc is obtained which yields a well denned infrared spectrum. A Beckman IR-5A spectrophotometer equipped with a beam condenser, scale expander, and auxiliary recorder is used for the examination. As little as 1 μg of sample has been used successfully for recording spectra of pure pesticides. The same order of sensitivity has been attained by using gas chromatographic fractions separated from pesticide mixtures.
Studies on the Biodegradability of Water-Insoluble Nitrogen Sources in Fertilizers
Authors: Katz Stanley E 
Published: February 2020

Abstract
A method was developed for water-insoluble nitrogen in fertilizers, based upon the principles of biodegradability used to determine the biological oxygen demand of wastes. By making the nitrogen content the limiting factor in the growth medium, the biodegradation of water-insoluble nitrogen sources could be studied. A relationship between oxygen utilization and nitrogen content allowed for fairly accurate measurement by means of a Warburg Respirometer. The per cent biodegradability of nine water-insoluble nitrogen materials was determined within 2 weeks. A comparison of the per cent ureaform biodegradability with some recently published agronomic studies was made.
Determination of Total Nitrogen in Fertilizers
Authors: Davis H A , Urban W E 
Published: February 2020

Abstract
Five methods, AOAC 2.037, 2.039, modified reduced iron, chromium powder, and Raney nickel catalyst powder for the determination of total nitrogen in fertilizers, were submitted to collaborators for study. Twelve laboratories participated and completed the work. No one method was “best.” The modified reduced iron, chromium powder, and Raney nickel catalyst powder methods gave essentially equal results, but the chromium powder method is favored for case of operation and time required. However, if considerable organic matter and nitrate are present in a sample, satisfactory results may not be obtained. The analyst should select the official method best suited to the makeup of the sample. It is recommended that the chromium powder method he adopted as official, first action, and that study be continued with the modified reduced iron and Raney nickel catalyst methods, including helpful proposals in developing a method that may be applicable to all fertilizers.
Determination of Isolated Trans Isomers by Infrared Spectrophotometry
Authors: Firestone David , LaBouliere Pauline 
Published: February 2020

Abstract
A study was made of the AOCS Tentative Method for Determining Isolated Trans Isomers by Infrared Spectrophotometry. Triglycerides with zero or low trans content produced isolated trans values which were about 2–3% high, whereas derived methyl esters produced values which were about 1.5–3% low. Corrections are suggested for analysis of samples of low isolated trans content. It is recommended that the AOCS Tentative Method be adopted as official, first action by the AOAC, applicable to margarines and shortenings.
How Rugged Are Our Nitrogen Methods?
Authors: Burgh W G , Brabson J A 
Published: February 2020

Abstract
Youden’s ruggedness test was made of two official methods and four more recent methods for the determination of total nitrogen in fertilizers containing nitrates. Among the variables tested were amounts of nitrogen and reductant, effect of chloride, and time of reaction of reductant.
Official method 2.039 (reduced-iron) failed the test. In order of increasing standard deviation, the five methods that passed the test were the chromous reduction method, Raney-catalyst-powder method, official method 2.037 (salicylic acid), improved reduced-iron method, and the chromiumpowder method.
Gradient Elution Chromatography of the Acids in Concord and Other Grape Juices and Jellies
Authors: Jorysch David , Marcus Seymour 
Published: February 2020

Abstract
The gradient elution technique was used to determine the acid profiles of grape juices and jellies prepared from their juices. Acids were separated by placing predetermined volumes of grape juices containing equal milliequivalents of free acid on columns of Dowex 1-X10 anion exchange resin in the formate form and eluting with formic acid in gradually increasing concentration. The eluates were collected in a fraction collector and evaporated to dryness on a waterbath, and the residues were titrated with standard alkali solution. The gradient elution chromatograms of the acids in Concord grape juice samples pressed in the laboratory differed only slightly from similar commercial samples. Grape juices other than Concord have similar acid patterns but show another acid peak. Grape jellies were liquefied and their acids determined by the method; the presence of added citric acid in these jellies is shown to affect the acidity patterns.
Revision of the AOAC Sediment Test for Milk
Authors: Joiner Curtis R 
Published: February 2020

Abstract
The revised method for preparing 1⅛″ diameter sediment standards and the new method for preparing 0.40″ diameter standards (presented last year) were studied collaboratively. Four collaborators prepared acceptable standards of both sizes. Study showed that vacuum nitration was superior to filtration by increased pressure above the liquid being filtered. New photographic standards of both sizes are now available from the U.S. Department of Agriculture. It is recommended that the revisions given in this paper be incorporated into 36.009–36.012, and that the revised method be adopted as official, final action.
Polarographic Determination of Organomercury Drugs
Authors: Hopes Ted M 
Published: February 2020

Abstract
Official NF, USP, and AOAC methods for organomercury drugs are long and determine only total mercury. Initial studies were made of the polarographic behavior of merbromin NF, on a Polarotrace Model K-1000. The peak current of a reduction peak that was found to be specific for the carbon-mercury bond was not directly proportional to concentration in pH 7.5 Britton-Robinson buffer-KCl solution. A much stronger peak, derived from another group in the molecule, exhibited a linear relationship between peak current and concentration in the 10–100 μg/ml range. Column and thin-layer chromatography of commercial merbromin indicates the presence of a number of compounds. Further work on the polarographic determination of merbromin will require the preparation of an adequate standard and a judgment of the therapeutic efficacy of the compounds present in merbromin preparations.
Hexestrol in Tablets
Authors: Matherne Mederic J 
Published: February 2020

Abstract
The phenolic properties of hexestrol are utilized to extract it from tablet excipients. This method is applicable to hexestrol alone in tablets. Hexestrol is extracted with chloroform from an acid medium; then iso-octane is added to the chloroform to reduce the polarity so that the hexestrol may be removed by NaOH extraction. The basic extracts are acidified and the hexestrol is finally extracted with chloroform and evaporated to dryness. An ethanolic solution of the hexestrol residue is scanned in the UV between 240 and 320 mμ hexestrol is measured quantitatively at 280 mμ
Determination of Dibrom and DDVP Residues in Some Fruit and Vegetable Crops by Microcoulometric Gas Chromatography
Authors: Boone George H 
Published: February 2020

Abstract
A rapid procedure has been developed for quantitative detection of Dibrom (dimethyl- l,2-dibromo-2,2-dichloroethyI phosphate) and DDVP (dimethyI-2,2-dichIorovinyl phosphate) in apples, cabbage, and carrots. Dibrom and DDVP are extracted from plant material with benzene, and interfering plant substances are removed from the extract by column chromatography. Microcoulometric gas chromatography is used for the determinative step. Recoveries of Dibrom at the 5.18 ppm level averaged 84.2% for apples, 86.2% for cabbage, and 86.9% for carrots. Recoveries of DDVP at the 5.06 and 3.75 ppm level averaged 89.0% for apples; at 5.00 and 5.06 ppm they averaged 87.9 and 83.7% for cabbage and carrots, respectively.
Increased Specificity in the Determination of Maleic Hydrazide
Authors: Hoffman I , Gordon A D , Parups E V 
Published: February 2020

Abstract
A study was condvicted to determine the effects of certain chemicals, either alone or with maleic hydrazide (MH), on the validity and applicability of the present colorimetric method for the determination of MH residues. This report presents the findings, together with procedure modifications, which should further increase the specificity of the analytical method.
Determination of Carbaryl Residues in Honey Bees
Authors: Johnson D P , Stansbury H A 
Published: February 2020

Abstract
A method has been developed for detecting residues of carbaryl (1-naphthyl methylcarbamate) as well as its hydrolysis product, 1-naphthol, in dead bees. The method is based on extraction of the bees with benzene, followed by a cleanup involving liquid partitioning and chromatography on Florisil. The quantitative determination involves hydrolysis of carbaryl to 1-naphthol and coupling of the latter with p-nitrobenzenediazonium fluoborate in acetic acid to form a yellow substance. For separate analysis, free 1-naphthol is separated from methylene chloride into a basic aqueous solution. The sensitivity of the method is about 0.1 ppm; recoveries averaged 85.6 ± 6.6% for 1- naphthol and 83.8 ± 2.7% for carbaryl.
Composition of Oil-Soluble Annatto Food Colors. III. Structure of the Yellow Pigment Formed by the Thermal Degradation of Bixin
Authors: Mckeown G G 
Published: February 2020

Abstract
The stereochemical structure of bixin is demonstrated in this paper by isolating the yellow hexaene pigment as the free acid, preparing its ethyl ester, and degrading it to its aromatic fragments, which were identified by gas chromatography. Results indicate that the described structure is correct.
Identification and Determination of Dichlone Residues in Treated Tobaccos
Authors: Hoffman I , Parups E V , Morley H V 
Published: February 2020

Abstract
Dichlone as a residue in tobacco was determined quantitatively by a spectrophotometric procedure following cleanup on a column of Florisil that had been slightly deactivated with water. Recoveries ranged from 93 to 100%. In a parallel study, dichlone was identified by thin layer chromatography. Results indicate TLC is suitable for screening.
Detection of Peanuts in Adulterated Tehina and Halva
Authors: Letan Arieh , Turzynski Berta , Raveh Ariela 
Published: February 2020

Abstract
A proposed method for detection and approximate estimation of peanut admixtures in adulterated tehina and halva (local sesame products) at a minimum level of 3–7% is presented which is based on the difference in behenic acid content of oils extracted from peanuts and sesame seeds. Long-chain saturated fatty acid esters from the analyzed mixture of methyl esters were isolated through urea complexing, and the gas chromatographic technique of analysis was used. Behenic acid was found to be present not only in peanut oil (as reported in the literature) but also in sesame oil in amounts not exceeding 0.3%.
Use of Thin Layer Chromatography and Phosphorimetry for Rapid Quantitative Determination of Biphenyl in Oranges
Authors: Mccarthy W J , Winefordner J D 
Published: February 2020

Abstract
Biphenyl, a widely used fungicide in citrus fruits, is quantitatively determined by initial extraction of the orange juice and pulp or peel, thin layer chromatographic separation of the biphenyl, and phosphorimetric measurement of the separated biphenyl. The ether extraction is quantitative and reproducible, and it requires less time than the lengthy steam distillations previously used. By the ether extraction method, the relative average deviation is only ± 0.2 ppm for orange juice and pulp containing 3.8–8.9 ppm biphenyl, and only ± 2 ppm for orange peel containing 39–65 ppm biphenyl. Thin layer chromatography quantitatively separates biphenyl from the orange essential oils, waxes, and other ether extractives in 15 minutes. Phosphorimetry provides an extremely sensitive and accurate final step in the analysis. Because the limit of detection of biphenyl by phosphorimetry is very low (4 × 10-3 µg biphenyl/ml solvent), an analysis can be carried out easily and accurately on an orange sample containing as little as 5 µg of biphenyl. The total time for the analysis of the biphenyl content in fovir different samples with four replicate determinations for each sample is approximately 2 hours.
Analysis of Imidan Colorimetrically and by Electron-Affinity Gas Chromatography
Authors: Bowman Malcolm C , Beroza Morton 
Published: February 2020

Abstract
A procedure for analyzing Imidan® colorimetrically is based on the acid hydrolytic cleavage of formaldehyde from the molecule and the determination of the liberated formaldehyde with chromotropic acid by the Eegriwe reaction. Recoveries of the pesticide from milk ranged from 75 to 88% in the 0.5–5.0 ppm range.
A gas chromatographic method, also devised, required less cleanup and was faster, more accurate, more sensitive, and more specific than the colorimetric procedure. Recoveries of Imidan from milk at levels of 0.01–5 ppm ranged from 93 to 101% ; from whole sweet corn plants recoveries at levels of 0.05–10.0 ppm were from 94 to 106%.
A Specific Bioassay Method for Determining Bidrin® Insecticide Residues
Authors: Sun Yun-Pei , Lau S C , Johnson Elmer R 
Published: February 2020

Abstract
A specific bioassay method based on the application of physico-chemical and biological techniques has been developed for the determination of Bidrin® (3-hydroxy-iV,Ardimethyl-cis-crotonamide dimethyl phosphate) residues. The experimental design, procedure, and evaluation of bioassay results are essentially the same as in a residue-film bioassay.
Interferences of most insecticides tested were less than 0.1% ; however, water-miscible insecticides, such as dimethoate and phosphamidon, gave relatively high interferences (1–6%). Mixtures containing 100-150 ppm of "less toxic" insecticides gave interferences of 0.6 to &lt; 0.03% of apparent Bidrin.
When several crops were fortified with 0.1–22 ppm of Bidrin, either before or after extraction, recoveries were satisfactory. About 0.05 ppm of Bidrin can be detected. The reproducibility of this method is comparable to that of a residue-film bioassay. The overall coefficient of variation is 8.8%. A comparison of results for several Bidrin-treated materials, obtained by a cholinesterase-inhibition method and the specific bioassay method, shows good agreement.
An Improved Raney Catalyst Powder Method for Determination of Nitrogen in Fertilizers
Authors: Burch W G , Brabson J A 
Published: February 2020

Abstract
With a Raney catalyst powder containing 10% Co, 40%; Ni, and 50% Al, nitrates are reduced to ammonia in 8N sulfuric acid in 10 minutes. Neither chlorides nor organic nitrogen compounds interfere with the reduction, and the reduction passed Youden’s ruggedness test. Results of analyses of fertilizers for total nitrogen that included reduction with the powder were in good agreement with those of accepted methods.