bluuebunny/crossref_metadata_2025_split huggingface dataset:
Test Method for Determination of Virucidal Efficacy of Liquid Surface Disinfectants
Authors: McDuff Charles R , Gaustad John W 
Published: February 2020

Abstract
A test method was developed incorporating AOAC use-dilution stainless steel Penicylinders and H.Ep.-2 tissue culture cells for the evaluation of disinfectants as virucides. The subsequent collaborative study using Herpes simplex and poliovirus type 1 in evaluation against a quaternary ammonium compound, phenolic, and iodiphor disinfectants indicated that the basic test procedure is sound. However, an improved virus concentration technique and a modified method for drying virus-contaminated cylinders are recommended. In addition, other types of disinfectants and test viruses should be included in order to demonstrate that the procedure is versatile as well as reproducible.
Rapid Digestion and Flameless Atomic Absorption Spectroscopy of Mercury in Fish
Authors: Dusci Leon J , Hackett Laurence P 
Published: February 2020

Abstract
A rapid method is described for the determination of total mercury in fish samples. The sample is digested with nitric acid-sulfuric acid-potassium permanganate, and then reduced and aerated for measurement by flameless atomic absorption spectrophotometry. The average recoveries of organic and inorganic mercury added to fish were 93 and 95%, respectively. The uniformity of mercury levels in shark tissue has also been investigated.
Modifications to the Hanus Iodine Absorption Number Method
Authors: Lewis Charles E , Croft Martin G 
Published: February 2020

Abstract
In using the Hanus method for determining the iodine absorption number of backfat from pigs, the blank determinations varied noticeably. Slight variations in temperature changed the volume of iodine solution dispensed, because the solvent, acetic acid, has a high temperature coefficient of expansion. For accurate, precise, and rapid determinations, the iodine solution should be measured by weight, not volume. Further modifications include the use of a stabilized indicator and a change in the dispensing of the weighed samples.
Environmental Chemistry of Substitutes for Polychlorinated Biphenyls. I. Composition and Properties of an Alkylchlorobiphenyl Product
Authors: Sundström Göran , Hutzinger Otto , Karasek Francis W , Michnowicz John 
Published: February 2020

Abstract
The composition of a technical alkylchlorobiphenyl mixture, proposed as a substitute for polychlorinated biphenyls, has been investigated by spectral and chromatographic methods. Gas-liquid chromatography-mass spectrometry revealed the presence of a large number of biphenyls substituted with 2–3 chlorine atoms and 0–4 isopropyl groups. The mixture was dechlorinated as a first step toward structure elucidation of the individual components. The behavior of the alkylchlorobiphenyls during analytical cleanup steps such as thin layer chromatography and chromic acid oxidation was also investigated.
Problems of Sampling and Analytical Methods
Authors: Horwitz William 
Published: February 2020

Abstract
The need for acceptable, reliable, and practical methods of analysis, chemical, physical, and biological, by the Food Standards Program of the Food and Agriculture Organization/World Health Organization is leading to cooperation by those organizations with the resources and experience to supply them. Methods should be shown to be workable and practicable and then validated in a properly designed international collaborative study for the efficient utilization of the time and effort of participating organizations and laboratories. The methods to be subjected to interlaboratory collaborative study should be clearly written so that the method itself is being tested without unauthorized variations. Satisfactory reference standard materials are often an essential part of the method. Uniform, international methods which have been developed through interlaboratory collaborative studies are applicable to the areas of microbiology and toxicology, as well as chemistry.
Pollution-Reduced Kjeldahl Method for Crude Protein
Authors: Rexroad Paul R , Cathey Robert D 
Published: February 2020

Abstract
Pollution from the Kjeldahl method for crude protein has been reduced by substituting a low level of copper (0.04 g CuSO4) for the mercury (0.7 g HgO) specified in the AOAC official method, 2.049. Adjustments were made in the salt-acid ratio so the new system could handle hard-to-digest samples in a reasonable time. The new method was rugged for lysine. HCl. It is designed to be used for crude protein in feeds or similar Kjeldahl work. Precision and accuracy were equal to or better than that for the official method in a study of 17 samples analyzed in duplicate on 3 different days. The following samples were used in the study: lysine. HCl, tryptophan, NBS standards, urea, meals, mixed feeds, grains, and forage. The average per cent nitrogen found was 9.52 by the official method and 9.53 by the copper method. The average standard deviation was 0.038 by the official method and 0.033 by the copper method, giving the corresponding relative standard deviations of 0.40 and 0.35%.
Collaborative Study of the Determination of Fat in Intermediate Moisture Pet Foods
Authors: Kuhn Gustav O 
Published: February 2020

Abstract
Four different semimoist pet food formulations representing a cross section of commercial products were studied collaboratively for fat content by 2 methods. Ten laboratories participated in the study. Direct petroleum ether extraction by AOAC method 7.045 yielded low and variable fat recovery. AOAC acid hydrolysis method 7.047 for fat in baked dog foods was satisfactory for semimoist pet foods. The method, with some editorial changes, was adopted as official first action for this type of pet food.
Cathodic Stripping Voltammetry of Nanogram Amounts of Selenium in Biological Material
Authors: Blades Michael W , Dalziel John A , Elson Clive M 
Published: February 2020

Abstract
A method is described to determine selenium in biological material, based on cathodic stripping voltammetry. Following wet ashing, the selenium was extracted into benzene as the 3′,4′-diaminophenylpiazselenol. The selenium was subsequently back-extracted into dilute acid for analysis. Analyses of NBS Bovine Liver demonstrated that the method was capable of recovering 96±9% of the selenium present. The detection limit and working range were 3 ng/g and 3–10,000 ng/g, respectively. The method was also applied to the determination of selenium in rapeseed oils and seed.
Determination of Added Blood in Ground Beef
Authors: Karasz Albert B , Andersen Ross , Pollman Roger 
Published: February 2020

Abstract
Blood added to ground beef is estimated from hemoglobin extracted with water. Since myoglobin is co-extracted with the hemoglobin, the 2 heme pigments are separated in one portion of the extract by precipitating the hemoglobin in an 85% (NH4)2SO4 solution. The myoglobin remaining in solution is used as the reference solution for determining the hemoglobin in another portion of the extract containing both pigments. The hemoglobin is converted to cyanomethemoglobin and quantitated by its absorbance at 422 nm.
Automated Fluorometric Method for the Determination of Total Vitamin C in Food Products
Authors: Roy Ram B , Conetta Aldo , Salpeter Jerry 
Published: February 2020

Abstract
A specific microfluorometric method for the determination of ascorbic acid, dehydroascorbic acid, and total vitamin C in food products has been automated. The procedure developed is an adaptation of the official AOAC method (secs. 43.056–43.062), except that N-bromosuccinimide is used instead of Norit to oxidize vitamin C. Ascorbic acid is selectively oxidized by N-bromosuccinimide before other interfering substances that may be present, so this method is a highly sensitive and specific technique with extensive applicability. The proposed automated method is simple, rapid, reliable, and sufficiently sensitive to analyze as little as 2 × 10−3 to 0.1 mg ascorbic acid/ml. Analytical results obtained for ascorbic acid, dehydroascorbic acid, and total vitamin C in a wide variety of food products are reported. The analytical system developed has the capability of analyzing 50 samples/hr.
High-Pressure Liquid Chromatography of Caffeine in Coffee
Authors: Madison Bryan L , Kozarek William J , Damo Cecilia P 
Published: February 2020

Abstract
A new method is described for the determination of caffeine in coffee, based on high-pressure liquid chromatography. The caffeine is extracted from the sample with water and/or methylene chloride, and then separated from interfering materials by passing an aliquot of the extract through a high-pressure column containing sulfonated cation exchange resin, using 0.01M nitric acid as the mobile phase. An ultraviolet detector measures the absorption of the solution directly. The method is rapid and eliminates the lengthy separations common to other methods. The procedure was applied successfully to decaffeinated and non-decaffeinated green, roasted, and instant coffees. This method gives a more accurate measure of the caffeine content in decaffeinated coffee samples than the micro Bailey-Andrew and modified Levine methods, with equal or better precision. This method gives results equal to those obtained by the official methods for non-decaffeinated samples.
Reference Raman Spectra of Eleven Miscellaneous Pesticides
Authors: Nicholas Mark L , Powell David L , Williams Theodore R , Thompson Robert Q , Oliver Nelson H 
Published: February 2020

Abstract
The Raman spectra of ICP (propham), CIPC (chlorpropham), carbaryl, EPTC (ethyl N,N-dipropyl (3-chlorophenyl) carbamate), pebulate, CDEC (2-chloroallyl diethyldithiocarbamate), thiram, maneb, zineb, ferbam, and nicotine have been recorded. These spectra are presented, along with tables giving values for the frequencies.
Comparison of Dieldrin, Lindane, and DDT Extractions from Serum, and Gas-Liquid Chromatography Using Glass Capillary Columns
Authors: Franken Josef J , Luyten Bert J M 
Published: February 2020

Abstract
Rats were given an oral dose of 14C-labeled chlorinated pesticides to obtain serum containing p,p′-DDT, dieldrin, or lindane. Simple hexane and formic acid-hexane extraction methods, involving pretreatment of the serum with formic acid, were compared by radiometric and by paper chromatographic and gas chromatographic analysis. In vivo binding of chlorinated pesticides to constituents of the serum does not necessarily prohibit their isolation by simple hexane extractions, provided that the extraction is very vigorous and at least 5 min long. Stable emulsions were broken by cooling in liquid nitrogen or Dry Ice-acetone. The hexane extraction method described yields quantitative recovery of the pesticides studied, whereas the formic acid-hexane method is quantitative for p,p′-DDT, 93% for dieldrin, and 89% for lindane. Gas chromatographic comparison of both methods, using human serum, shows that the hexane method extracts 16% more β-BHC, 7% more dieldrin and HCB, and 4% more p,p′-DDE from serum than does the formic acid-hexane method. The difference for p,p′-DDT is not significant. Gas chromatography with glass capillary columns and an all-glass solids injection system yielded detection limits as low as 15 fg. Data show that the use of an internal standard considerably improves the precision of quantitation.
Collaborative Study of a Modified Extraction Procedure for Lasalocid Sodium in Feeds by Microbiological Assay
Authors: Scheiner Jacob M 
Published: February 2020

Abstract
A collaborative study was conducted on a modified extraction technique in the microbiological determination of lasalocid sodium in finished poultry feeds. The feed is warmed briefly with pH 4.7 buffer and the drug is extracted with ethyl acetate. The extract is washed with HCl and NaOH and evaporated to dryness, and the residue is dissolved in hexane, partitioned into methanol-water (3+1), and diluted to assay range at a final alcohol concentration of 25% (v/v). Seven laboratories participated in the study. Average recoveries of lasalocid sodium added at 0.01035, 0.00863, and 0.0069% ranged from 93 to 99% for mash feeds and from 86 to 95% for pellets. The coefficients of variation averaged 11.2% for mashes and 9.8% for pellets. The modified extraction technique has been adopted as official first action.
Rapid Colorimetric Method for Carbadox in Animal Feeds
Authors: Thorpe Virginia A 
Published: February 2020

Abstract
The colorimetric method for carbadox in animal feeds was modified to be simpler and faster. Carbadox is extracted with dimethylformamide and separated from interferences on an alumina column in the absence of water by controlling the amount of sample extract on the column and the flow rate. The isolated carbadox is eluted into sodium hydroxide and the resultant yellow chromophor is measured spectrophotometrically at 420 nm.
Preparation and Spectral Compilation of FD&C Red No. 40 Intermediates and Subsidiary Dyes
Authors: Bell Sandra J 
Published: February 2020

Abstract
FD&C Red No. 40 may contain higher or lower sulfonated subsidiary dyes, depending on the purity of intermediates used. Samples of 10 possible subsidiaries were prepared and purified. They are to serve as analytical standards to aid in the identification of unknown compounds frequently appearing during the analysis of certification samples. Visible, ultraviolet, and infrared spectra as well as absorptivities and molar extinction coefficients are given for each dye.
Gas Chromatographic Determination of Micro Amounts of Cyanide Residues in Wines, Distilled Liquors, and Other Alcoholic Beverages
Authors: Bates Brian L , Buick Donald R 
Published: February 2020

Abstract
A gas chromatographic method for the determination of cyanide residues in alcoholic beverages has been developed from procedures previously reported for application to water samples. Quantitatively isolating HCN from alcoholic beverages presented difficulties not encountered with aqueous solutions, particularly in the presence of SO2 in the sample. HCN was liberated from the acidified sample by heating at 70°C, flushed into an NaOH absorber solution, converted to cyanogen bromide (CNBr), extracted into diisopropyl ether, chromatographed on a Porapak Q column, and detected by an electron capture detector. SO2 that is present in most wines interfered with the bromination step and caused low recoveries. This interference was eliminated by initially converting any cyanide present in the sample to the stable mercuric cyanide salt and then purging the acidified sample solution of all SO2. The Hg(CN)2 present was then dissociated by adding KI and the analysis proceeded as previously described. Mean recoveries of 80–97 % were obtained for 2–20 μg cyanide from replicate analyses of spiked samples of distilled liquors free of SO2. The relative standard deviations ranged from 6.1 to 11.1%. Mean recoveries of 65 to 91% were obtained in the same range of cyanide from replicate analyses of spiked wine samples known to contain SO2, with relative standard deviations ranging from 0.8 to 10.2%. The limit of detection was 0.2 μg HCN.
Thin Layer Chromatographic Identification of Some Sympathomimetic Amines
Authors: Shah Jitendra J , Shah Ramila J 
Published: February 2020

Abstract
Thin layer chromatographic behavior of some sympathomimetic amines in the presence of acids in neutral and organic solvent systems is reported. The sympathomimetic amines were dissolved in 0.1N HCl or ethanol and treated with bromocresol green or p-nitrobenzoyl chloride reagents on fiber sheets or precoated glass plates. Two-, 3-, and 4-component solvent systems were tested. Benzene-ethyl acetate gave 2 spots for each amine standard; the more polar spots were satisfactorily separated. Amines in pharmaceuticals were not separated by any solvent system tested.
High Performance Liquid Chromatographic Analysis of Supplemental Vitamin E in Feed
Authors: Shaikh Badaruddin , Huang Hsinkuang S , Zielinski Walter L 
Published: February 2020

Abstract
Supplemental vitamin E is extracted from feed in one step with methanol and analyzed by reverse phase partition chromatography in less than 10 min, using isocratic elution with either methanol or water-methanol as the mobile phase. Detection response (as measured by peak area) was linear between 0.5 and 3.0 μg, and the coefficients of variation for retention time and peak height on replicate analyses of the standard sample were 0.8 and 2.3%, respectively.
Determination of Pirimiphos Methyl in Formulations by High Performance Liquid Chromatography
Authors: Zehner James M , Simonaitis Richard A 
Published: February 2020

Abstract
A simple and rapid method for the determination of pirimiphos methyl (O-[2-(diethylamino)-6-methyl-4-pyrimidinyl] O,O-dimethyl phosphorothioate) in formulations by high performance liquid chromatography is described. The sample is dissolved in methanol, and biphenyl is added as an internal standard. Then the sample is chromatographed by reverse phase chromatography on a Zipax octadecylsilane column. A 4 μI injection containing 0.01% pirimiphos methyl produces a 50% full scale peak at the maximum absorbance at 254 nm.
High Pressure Liquid Chromatographic Determination of Uncombined Intermediates in FD&C Red No. 2
Authors: Singh Manjeet 
Published: February 2020

Abstract
A high pressure liquid chromatographic (HPLC) method is presented for the separation and determination of uncombined intermediates in FD&C Red No. 2 (amaranth). Samples of FD&C Red No. 2 containing 0.1—0.3% naphthionic acid, 0.1—0.4% 2-naphthol-3,6-disulfonic acid, 0.3—1.0% 2-naphthol-6,8-disulfonic acid, and 2-naphthol-3,6,8-trisulfonic acid were prepared and analyzed by HPLC. Recoveries ranged between 92 and 101%. Twenty samples of FD&C Red No. 2 were analyzed by the conventional column chromatographic method and the HPLC method. The HPLC method was superior, since it separated all the above intermediates from each other and from FD&C Red No. 2 in one quarter the time required by the conventional column chromatographic method which did not separate the individual intermediates.
Electron Impact and Chemical Ionization Mass Spectrometry of Some Butyrophenones
Authors: Leferink Jos G , Maes Robert A A 
Published: February 2020

Abstract
The mass spectra of some butyrophenoncs are presented. Electron impact ionization and chemical ionization with isobutane as the reagent gas are compared. The chemical ionization spectra show the quasi molecular ion (M + H)+ to be the most abundant ion. Important fragments in the electron impact spectra are discussed for easy determination of other similar compounds.
Evaluation of XAD-2 for Multiresidue Extraction of Organochlorine Pesticides and Polychlorinated Biphenyls from Natural Waters
Authors: Coburn John A , Yaldmanis Ilze A , Chau Alfred S Y 
Published: February 2020

Abstract
The Amberlite polymeric resin, XAD-2, was evaluated for multiresidue extraction of ng/L levels of several organochlorine pesticides and polychlorinated biphenyls (PCBs) from fortified distilled water and from fortified and unfortified natural waters.
Recoveries from 1 L distilled water samples fortified with 10—100 ng of 10 organochlorine pesticides averaged 96%. Recoveries averaged 85% for XAD-2 resin extraction of fortified natural samples collected from across Canada. Unfortified control samples contained no detectable levels of any of the pesticides used in the fortification. The resin is not suitable for extracting Mirex from natural water; only about 50% of added Mirex was recovered. Recoveries of PCBs from 2 L natural water samples, fortified with 250 ng PCBs/L and corrected for losses on the silica gel fractionation column and apparent PCB content of the control samples, ranged from 78 to 86%. Blanks for the resin extraction procedure were very low, averaging 4 ng PCBs/L.
Temperature-Programmable Furnace for Ashing of Foods in Trace Metal Analysis
Authors: Holak Walter 
Published: February 2020

Abstract
The use of a programmable furnace in preparing samples for determining cadmium, lead, copper, and zinc by differential pulse anodic stripping voltammetry or atomic absorption spectrophotometry is convenient and timesaving. Recovery data for these 4 metals in various foods (tuna, sardines, and milk) were 93— 96% for 0.01—1 ppm cadmium, 96—114% for 0.05—5 ppm lead, 100—108% for 2—10 ppm copper, and 97% for 10 ppm zinc.
Quantitative Determination of Spleen Added to Ground Beef
Authors: Bittel Ralph J , Graham Paul P 
Published: February 2020

Abstract
A method for the quantitative detection of spleen added to ground beef is presented, based on the organ specificity and insolubility of the storage iron compound hemosiderin. Soluble iron forms are removed by saline extraction and centrifugation. Iron remaining in the insoluble tissue residue is assumed to be hemosiderin iron. The retained iron is extracted by acid hydrolysis of the residue in a solution of 2% thiourea in 1N HCl, filtered, and measured colorimetrically with ferrozine and by atomic absorption spectroscopy. Weighed amounts of ground beef and a composite spleen homogenate were combined to yield products with 0, 2.5, 5, and 10% spleen. A graded series was prepared at each of 3 fat levels. The residues from unadulterated samples retained less than 4 μg Fe/g original sample. Insoluble iron increased linearly (slope = 4.83) as the level of spleen in the product increased. The fat content of the products had little effect on the determination of added spleen.
High Performance Liquid Chromatography of Aflatoxins in Cottonseed Products
Authors: Pons Walter A , Franz Anthony O 
Published: February 2020

Abstract
A precise and sensitive high performance liquid chromatographic (HPLC) method is proposed for determining aflatoxins in cottonseed products in 1.0—1.5 hr. After aqueous acetone extraction, lead acetate treatment, and partition of aflatoxins into methylene chloride, sample extracts are purified on a small silica gel column requiring only 125 ml solvent/sample. Aflatoxins B1 and B2 in the purified extract are resolved on a micro particulate (10 μm) silica gel column in ca 8 min, using a water-saturated chloroform - cyclohexane - acetonitrile solvent, with detection by ultraviolet absorbance at 365 nm. The resolution was highly reproducible, giving coefficients of variation of 0.2—1.0% for retention and 1.0—2.3% for quantitation. Recovery of added aflatoxins B1 and B2 was 90— 95% at levels of 5—100 μg/kg. The within-laboratory coefficients of variation of the entire method, based on repetitive assays of a cottonseed meal (34 μg B1/kg, 6 μg B2/kg), were 7.3% (B1) and 7.4% (B3). A high degree of correlation was obtained for HPLC estimation by 2 different commercial columns; for quantitation by peak height vs. electronic integration; and for quantitation by HPLC or thin layer chromatography.
Fungal Growth and Aflatoxin Production on Apiarian Substrates
Authors: Hilldrup Jo Ann L , Eadie Thomas , Llewellyn Gerald C 
Published: February 2020

Abstract
Unprocessed honey, Lilium longiflorium pollen, brood comb, whole larvae, and whole bees were inoculated with Aspergillus flavus NRRL 3251, A. flavus ATCC 15548, and A. parasiticus NRRL 2999. The fungi grew, sporulated, and produced various amounts of aflatoxin on all substrates except the unprocessed honey. The largest quantity of aflatoxin B1 was produced on whole larvae supporting A. flavus NRRL 3251 growth. A. parasiticus NRRL 2999 growing on whole larvae produced the most aflatoxin G1. Aflatoxins B2 and G2 were seldom detected. Apiarian substrates with the exception of honey seem capable of supporting fungal growth and resultant aflatoxin production.