bluuebunny/crossref_metadata_2025_split huggingface dataset:
Measurement of Residues of Cygon Insecticide and Its Oxygen Analog by Total Phosphorus Determination after Isolation by Thin-Layer Chromatography
Authors: Steller W A , Curry A X 
Published: February 2020

Abstract
A total phosphorus method incorporating thin-layer chromatographic isolation is described for the determination of Cygon Insecticide (generic name, dimethoate) and its oxygen analog. Residues of the insecticides are extracted from macerated plant tissue, and the extract, after solvent partitioning and concentration, is spotted on a thin-layer chromatographic plate. After development of the plate, the areas corresponding to the two compounds are scraped and eluted. The phosphorus content of the respective eluates is determined by an improved molybdenum blue method, and concentrations of dimethoate and its oxygen analog in the original samples are calculated.
Determination of Chlorinated Pesticide Residues in Fat by Electron Capture Gas Chromatography
Authors: Mccully K A , Mckinley W P 
Published: February 2020

Abstract
A general screening method has been developed for the cleanup and estimation of chlorinated pesticide residues in fats and oils. The fats were dissolved in benzene-acetone (1 + 19) and then precipitated at — 70 °C. The precipitated fat was removed by filtration through a column of Darco G-60 and Solka Floe in a jacketed filtering funnel. The filtrate was concentrated to a standard volume and an aliquot was analyzed by electron capture gas chromatography. With the exception of a few pesticides in butterfat and aldrin in beef fat, recoveries were 81 to 112% after a mixture of 12 chlorinated pesticides had been added to the fats prior to precipitation.
A Pyrex gas chromatographic column containing a 10% stationary phase of mixed silicones (4% SE-30 methyl silicone + 6% QF-1 fluoro silicone) was used to resolve this pesticide mixture. The compounds eluted from the column in the following order: lindane, heptachlor, aldrin, Telodrin, heptachlor epoxide, p,p’-DDE, dieldrin, o,p’-DDT, Rhothane, p,p’-DDT, endrin, and methoxychlor.
Identification of Grape Varieties
Authors: Rice A C 
Published: February 2020

Abstract
A series of grape juices and concentrates were diluted with Macllvaine’s buffer at pH levels ranging from 2 to 8 and analyzed spectrophotometrically. The relationship of various Concord and California grape juice samples from different geographical areas were characterized individually and in combination. The spectral characteristics of Concord and Salvador grape juice were found to be similar except at pH 7, where the Concord curve has two peaks (583 and 450 mμ) and the Salvador curve has only one. The anthocyanin components in Concord grape juice were studied chromatographically for an explanation of its unique spectral response at pH 7. Results are incomplete, and further study is recommended.
Iodine-131 in Foods
Authors: Velten Richard J 
Published: February 2020

Abstract
Two collaborative studies have been conducted on the determination of 1-131 in milk. In the first study, eight collaborators analyzed four samples ranging from 58 to 227 pc/L 1-131, but results were inconclusive. In the second study, 15 collaborators reported results for two samples. Results were much better. A third study is planned, on the basis of which a method will be proposed for adoption.
Colorimetric Determination of Oxyphenisatin and Oxyphenisatin Diacetate in Pharmaceutical Preparations
Authors: Major Antoine 
Published: February 2020

Abstract
A method is described which will quantitatively determine 0.1 mg oxyphenisatin or the diacetate in various pharmaceutical preparations. After removal of interferences by organic solvent extractions from aqueous solution and partition column chromatography, the reaction of oxyphenisatin (diacetate) with silver nitrate in alcoholic sodium hydroxide solution produces a violet solution, which follows Beer’s law (1—15 μg per ml). The method was satisfactorily applied to the assay of commercial tablets, liquids, and powders with recoveries, as per cent found of declared, in the range 95—101%.
Total Solids and Ether Extract in Fish and Other Marine Products
Authors: Risley H M 
Published: February 2020

Abstract
The first action rapid modified Babcock method for crude fat in canned fish (18.013) was again studied collaboratively. Two samples of fresh (unfrozen) fish were examined by 6 analysts in 3 different laboratories. The same fish (frozen) together with samples of canned tuna, canned salmon, and a mixture of raw sablefish and canned tuna were examined by a total of 12 analysts in 6 different laboratories. Each analyst also determined fat by the official acid hydrolysis method (18.012). The results show that the rapid modified Babcock method (18.013) has the same degree of reliability as the acid hydrolysis method; it has been rewritten for greater clarity following the suggestions of the collaborators, and the revised form is recommended for adoption as official, final action.
Malt Beverages, Sirups, Extracts, and Brewing Materials
Authors: Stone Irwin 
Published: February 2020

Abstract
A review is given of the collaborative work conducted by the committees of the American Society of Brewing Chemists for the two methods (sulfur dioxide in beer and hop acids by spectrophotiontometry) previously presented for adoption by the AOAC. Eight new methods have been accepted by the ASBC for publication and are in various stages of editorial completion.
Total Volatile Acidity in Wines
Authors: Gowans W J 
Published: February 2020

Abstract
The determination of the total volatile acidity of wines has been studied collaboratively, using modern equipment now available. Procedures studied employed the Cash Electric Still and conventional apparatus, an all-glass unit. Results were good on both types of apparatus and between collaborators. It is recommended that the method, using either type of apparatus, be adopted as official, first action.
Safflower Oil: Physical and Chemical Properties, and Fatty Acid Composition
Authors: Ibrahim Walld , Iverson John , Firestone David 
Published: February 2020

Abstract
Some physical and chemical properties, including fatty acid composition by gas chromatography, of 15 commercially refined safflower oils and three crude oils extracted from safflower seed, were determined. The average and standard deviations found were: refractive index, 1.4748 ± 0.0003; specific gravity, 0.9210 ± 0.0005; iodine number, Wijs, 143.4 ± 1.4; squalene, 7.1 mg/100 g ± 1.1; and Bellier test, 7.4° ± 0.9. The major fatty acid components were; palmitic 6.7 ± 0.3, stearic 2.7 ± 0.4, oleic 12.9 ± 0.6, and linoleic 77.5 ± 1.1. Minor fatty acid components detected were myristic, arachidic, and eicosenoic acids.
Colorimetric Determination of Nemacide and Ronnel in Animal Tissues
Authors: Claborn H V , Ivey M C 
Published: February 2020

Abstract
colorimetric method is described for determining Nemacide® and ronnel in the body tissues of sheep and cattle. After extraction and suitable cleanup, the insecticide is hydrolyzed and the resulting 2,4-dichlorophenol or 2,4,5-trichlorophenol is steam distilled. The phenols are reacted with 4-aminoantipyrine; the colored compound is extracted into a nitromethanepyridine mixture and the absorbance determined at 490 mμ. Recoveries of 88-95% are possible when known amounts of Nemacide are added to the tissues. The method will detect residues as small as 0.05 ppm of Nemacide, and preliminary tests indicate that it is equally sensitive for the determination of ronnel.
Analysis of Lipsticks. II. Chromatographic Separation of Castor Oil-Oleyl Alcohol Mixtures
Authors: Gross Frederick C , Newburger Sylvan H 
Published: February 2020

Abstract
Absorption chromatography with silica gel as the adsorbent was used to separate castor oil-oleyl alcohol mixtures, alone or in the presence of a lipstick base. Results show that oleyl alcohol can be eluted with isopropyl ether-isooctane (65+35) and castor oil with ethyl ether-isooctane (10+30). Identification was made through the infrared spectra of the residues from the eluates.
Reduction of Nitrates in Acid Medium with Raney Catalyst Powders
Authors: Brabson J A , Burch W G 
Published: February 2020

Abstract
Of several Raney catalyst powders (alloys of aluminum with other metals), the most efficient reduetant of nitrates in acid medium was that of Al and Ni; others, in decreasing order of reducing power, were Cu-Al, Ni-Cr-Al, Co-Al, and Fe-Al. In the reduction, nascent hydrogen, generated by the reaction of Al with the acid, is adsorbed on the alloying metal and there reduces the nitrate. A relatively small amount of the alloy is required, and the resulting salts do not interfere with subsequent Kjeldahling and distillation. The method was applied successfully to mixed fertilizers containing nitrates and to mixtures of potassium nitrate with organic materials that are occasional constituents of fertilizers. The method is suitable for solid and liquid fertilizers that contain considerable chloride.
Evaluation of Two Modifications of the Volumetric Ammonium Molybdate Method for Phosphorus
Authors: Hoffman W M , Woolson E A 
Published: February 2020

Abstract
Results are given on a collaborative study for total phosphorus, comparing two volumetric procedures with the “quimociac” modification of the gravimetric quinoline molybdate method. While the NPFI volumetric method seems to be capable of giving accurate phosphorus values its precision is not as yet acceptable; the technique of end point detection needs further study. A ruggedness test showed a significant difference between the use of 0.4 ml of phenolphthalein and electrometric titration to pH 7.85. The TVA volumetric procedure exhibited a trend to lower values than those by the QM method. Even though the differences between the methods are not statistically significant, this negative bias should be eliminated if possible. The results of the quinoline molybdate method further emphasize the recognized accuracy and superior precision of this method. The quimociac modification of the quinoline molybdate method warrants official, final action status.
Identification and Analyses of Five Organophosphate Pesticides: Recoveries from Crops Fortified at Different Levels
Authors: Storherr R W , Getz M E , Watts R R , Friedman S J , Erwin F , Giuffrida L , Ives F 
Published: February 2020

Abstract
The recoveries of five parent organophosphate pesticides from eight different fortified crops were determined hy a “gross” cleanup technique. The primary method of analysis. was GLC. Other determinative methods used for comparison were total phosphorus determination, paper chromatography, and determination of phosphorus esters with p-nitrobenzyl pyridine reagent. The five organophosphate pesticides studied as mixtures and individually were Diazinon, methyl parathion, parathion, malathion, and Trithion. The three fortification levels in crops were 5.0, 1.0, and 0.1 ppm.
Investigation of Two Gas Chromatographic Techniques for the Determination of Organophosphate Pesticide Residues
Authors: Giuffrida Laura , Ives Fred 
Published: February 2020

Abstract
Gas chromatography has been used in a recovery study for the development of a cleanup procedure for organophosphate pesticide residues in various crops. The effluent from one column was divided evenly between two detectors to obtain a dual analysis. A sodium thermionic detector, highly sensitive to phosphorus compounds, was used to give quantitative recovery data. A flame ionization detector was used to determine the efficiency of the cleanup.
Low Boiling Aromatics in Petroleum Fractions by Gas Chromatography
Authors: Klayder T J 
Published: February 2020

Abstract
A sensitive and very specific gas chromatographic method for low boiling aromatics in gasoline has been developed. A gas chromatographic column with Bentone 34 and Versilube F-50 gives an efficient separation of the aromatics. A heated, UV flow-through cell operated at 189.25 mμ shows good sensitivity with practically no interference from low boiling paraffins or saturated cyclic hydrocarbons such as cyclohexane.
Synthesis of Arsanilic-As74 Acid and Arsanilic-l-C14 Acid
Authors: Fredrickson R L , Bocchieri S F , Glenn H J , Overby L R 
Published: February 2020

Abstract
Arsanilic-As74 acid and arsanilic-l-C14 acid (p-aminophenyl arsonic acid) were synthesized in 20–30% yield with high radiopurity by way of the Bart reaction. Appropriately labeled p-nitrophenyl diazonium borofluoride and sodium arsenite were coupled, and the resulting labeled p-nitrophenyl arsonic acid was reduced to arsanilic acid by treatment with iron and hydrochloric acid. Purification procedures are described.
The Specificity of Di-(2-ethylhexyl) Phosphoric Acid (HDEHP) Method for Yttrium-90 in Foods: Modification for Fresh Heavy Fallout Conditions
Authors: Arnold Alphonso , Davis Sidney 
Published: February 2020

Abstract
Di-2-ethylhexyl phosphoric acid reagent from two commercial sources was investigated for a study of specificity of determining yttrium-90. Titration curves indicate no significant quantity of monoalkyl phosphoric acid ester, the only limiting impurity expected. The following radionuclides in pure solution were examined for removal of activity from yttrium-90: Ru-106/Rh-196, Zr-95/Nh-95, Ce-144/Pr-144, Ca-45, Mo-99, Zn-65, Cr-51, Fe-59, Ba-140/La-140, Cs-137, Nd-147/Pr-147. Both sources of reagent were highly effective in removal of activity of the introduced radionuclide. The removal of activity to within 0.1% of that initially introduced was demonstrated in all cases except the Ce-144/Pr-144 pair; in this case activity was reduced to within the 0.1% range by substituting a 0.1M HC1 wash for the normal wash at pH 1.4. Data arc included for the precision of the HDEHP method relative to picocuries of food ash analyzed and the standard deviation of the analysis.
New Penicillin G Working Standard: A Collaborative Study
Authors: Kirshbaum Amiel , Arret Bernard , Wilner Jerome 
Published: February 2020

Abstract
A proposed new penicillin G standard has been assayed collaboratively by eight laboratories. The mean “as is” potency obtained was 1642 u/mg with 95% confidence limits of 1631–1652 u/mg. On the basis of this study, the proposed standard has been adopted as the new official working standard.
Microbiological Assay for Bacitracin in Animal Feed
Authors: Craig G H 
Published: February 2020

Abstract
Eight samples of two types of bacitracin in broiler rations were assayed collaboratively by eight laboratories. One group contained 4, 6, 20, and 40 g of zinc bacitracin per ton; another group contained similar concentrations of bacitracin methylene disalicylate. Known amounts of bacitracin blended into feed were recovered: 80.5 and 71.9% from the 4 g/ton samples; 75.4 and 74.6% from the 6 g/ton; 101.0 and 102.2% from the 20 g/ton; and 97.3 and 97.0% from the 40 g/ton samples. Coefficients of variation of the assays were 29, 9 and 30.1% for 4 g/ton samples, 29.9% for 6 g/ton, 11.7 and 13.4% for 20 g/ton, and 11.0 and 11.8% for the 40 g/ton samples. The method is recommended for adoption as official, first action for samples containing 20 g/ton or more bacitracin.
Fluorometric Determination of Amprolium in Feeds
Authors: Szalkowski C R 
Published: February 2020

Abstract
A fluorometric method for the analysis of amprolium in feeds was studied collaboratively. The method is equivalent in sensitivity and reproducibility to the official AOAC method; however, bias is evident when antibiotics, except procaine penicillin and chlortetracycline, are mixed with amprolium. The method involves extraction with trichloroacetic acid; development of a fluorophor with sodium hydroxide, silver nitrate, and potassium ferricyanide; and measurement of fluorescence on a suitable photofluorometer. The method is applicable to feeds down to 40 ppm of amprolium.
Comparative Study of the Anthranilic Acid Esters by Ultraviolet Spectrophotometry, Colorimetry, Gravimetry, and Gas-Liquid Chromatography
Authors: Brunelle Richard L , Martin Glenn E , Ohanesian V G 
Published: February 2020

Abstract
A rapid and specific gas-liquid chromatographic method has been developed for the separation and quantitative determination of methyl and ethyl anthranilate in grape extracts and imitation grape flavors in the presence of interfering substances. Total methyl and ethyl anthranilate can be quantitatively determined in imitation grape flavors by ultraviolet spectrophotometry after steam distillation of the sample. Methyl and ethyl anthranilate show a characteristic peak at 335 mμ. Results for methyl and ethyl anthranilate by gas-liquid chromatography and ultraviolet spectrophotometry are compared with those obtained by the official AOAC methods.
Colorimetric Method for Determining Residues of Thimet (Phorate)
Authors: Winnett George , Katz Stanley E 
Published: February 2020

Abstract
A colorimetric method developed for Thimet eliminates many of the objectionable features of other methods currently in use. The procedure is fairly sensitive, requires little cleanup, and, except for minor alteration of standard laboratory glassware, requires no specialized equipment. Thimet and its metabolites are completely extracted from the plant material by chloroform, an aliquot is passed through a Florisil column, and the chloroform is evaporated. The residue containing Thimet and its oxidative products is picked up in a hexane-acetonewater system. The oxidized metabolites are removed by partitioning into the acetonewater phase. The hexane phase, containing Thimet, is evaporated to dryness and hydrolyzed with 48% hydrobromic acid. The hydrogen sulfide thus generated is determined colorimetrically as methylene blue.
Gas Chromatography of Unsaponifiable Matter. III. Identification of Hydrocarbons, Aliphatic Alcohols, Tocopherols, Triterpenoid Alcohols, and Sterols Present in Olive Oils
Authors: Eisner Jerome , Iverson John L , Mozingo Alfred K , Firestone David 
Published: February 2020

Abstract
Olive oils, both foreign and domestic, were saponified, and the unsaponifiable matter was fractionated on a Florisil column. Gas chromatography of the first two hydrocarbon fractions confirmed that squalene was the major component of pressed and solvent-extracted pomace oils. However, iso-and/or anteiso- tctratriacontane was the major hydrocarbon in olive kernel oil. Hydrogenation and temperature programming indicated that there were several homologous series present, consisting of normal, iso-and/or anteiso-, and multiple branched chain hydrocarbons. Gas chromatography of the third Florisil fraction (tocopherols, high molecular weight aliphatic alcohols, and triterpenoid alcohol components) indicated the presence of three homologous series of normal, iso- and/or anteiso-, and multiple branched chain alcohols. The triterpenoid alcohols were used to distinguish between pressed and solvent-extracted pomace oils. As little as 5% of pomace oil could be detected in laboratory-prepared mixtures. Campesterol and beta-sitosterol were the two sterols present in olive oils. The Fitelson test detected olive oils consisting entirely or largely of pomace oils.
The Determination of Mono-, Di-, and Triglycerides in Monoglyceride Concentrates by Column Chromatography
Authors: Distler E , Baur F J 
Published: February 2020

Abstract
A method for the quantitative determination of mono-, di-, and triglycerides was studied collaboratively. Samples are adsorbed on silica gel columns and the glycerides are separated by benzene, benzene plus 10% ethyl ether, and ethyl ether alone. Eight samples can be run simultaneously with an average standard deviation of 0.6–1.0%. Nine collaborators obtained average recoveries of 96, 100.3, and 102% for mono-, di-, and triglycerides, respectively.
Rapid Flame Photometric Method for Potassium in Fruit
Authors: Boland Frederick E 
Published: February 2020

Abstract
The flame photometric method of Pro and Mathers for potassium in wines and distilled spirits has been adapted to the analysis of sample solutions of fruit and subjected to collaborative testing. A sample solution of fruit is prepared and aspirated directly into the flame photometer. This eliminates the need for ashing the sample and thus saves time. Six Food and Drug Administration District Laboratories, two State Laboratories, and the Associate Referee participated in the collaborative study. The results indicated that the method is sufficiently accurate for the determination of potassium in frviits.
Collaborative Study of Rotenone Methods
Authors: Rund Robert C , Hambleton Larry G 
Published: February 2020

Abstract
Samuel’s infrared procedure continues to show close agreement with the crystallization method. The ultraviolet procedure differed appreciably from the crystallization method and the question of acetone vs. chloroform as the extractant for powdered cube roots is raised. Results from 13 laboratories on 5 samples by the 3 methods are reported and evaluated. Continued study on each of the official, first action methods is recommended.
Collaborative Study of Chlordane by Spectrophotometric Method
Authors: Malina Marshall A 
Published: February 2020

Abstract
Chlordane reacts with a methanolic solution of diethanolamine and potassium hydroxide to form a wine-red product. The intensity of the color is proportional to chlordane concentration and is used as a specific quantitative measure of the assay of chlordane formulations. Eight laboratories made a collaborative study of this method on six formulations. These formulations included all the general types used: granular, dust, emulsifiable concentrates, and oil solutions. Results show that the method is reliable; the coefficient of variation is less than 5%. The method was adopted as official, first action.
Quantitative Determination of Phenylephrine Hydrochloride by Column Acetylation Technique
Authors: Clark William R , Rosenberg Lynn A 
Published: February 2020

Abstract
determination of phenylephrine hydrochloride in combination with other amine-type drugs. The mixture is placed on a sodium borate-Celite column and the nonphenolic amines are removed with chloroform. The phenylephrine remaining on the column is acetylated and removed with a chloroform wash. The acetylated phenylephrine is then saponified with alcoholic KOH and determined spectrophotometrically against standard phenylephrine at about 290 mμ. Recoveries averaged 98.5% with a range of 93.3–101.7%. Mean deviation from the average was 1.8%. The method was adopted as official, first action.
Analysis of Diphenylhydantoin and Phenobarbital Mixtures
Authors: Marino Victor S 
Published: February 2020

Abstract
Diphenylhydantoin and phenobarbital are separated by column partition chromatography using a favorable solvent pair with pH control. Both drugs are solubilized by 15% re-amyl alcohol in chloroform (mobile phase) while saturated trisodium phosphate solution (immobile phase) selectively traps phenobarbital. Spectrophotometry is used to determine both substances quantitatively. Average recovery results of nine collaborators are 101.46% for diphenylhydantoin and 100.46% for phenobarbital with respective average standard deviations of 1.10 and 0.30. The method was adopted as official, first action.
Piperazine in Drugs by Near Infrared Spectrophotometry
Authors: Mohn L 
Published: February 2020

Abstract
A method for the analysis of piperazine in drug formulations has been developed. The piperazine base, or its salt, is dissolved in water, and the solution is made strongly alkaline. The base is then extracted with chloroform and diluted to a definite volume, and the clear extract is examined by near infrared spectrophotometry. A collaborative study has been made this year on two authentic preparations. A mean recovery of 101.7% with a standard deviation of ± 0.99% was observed for a sugar sirup and a mean recovery of 100.9% with a standard deviation of ± 1.30% was observed for a powder. Collaborators report that the method is rapid, simple, and straightforward.