bluuebunny/crossref_metadata_2025_split huggingface dataset:
Perchlorination of Polychlorinated Biphenyls
Authors: Huckins James N , Swanson Jerome E , Stalling David L 
Published: February 2020

Abstract
A simple and efficient method for the perchlorination of polychlorinated biphenyls (PCBs) to decachlorobiphenyl, using antimony pentachloride, is described. Average yields of decachlorobiphenyl from 3 individual samples of Aroclors 1016 and 1254 were 85 and 104%, respectively. Bromine was identified as a contaminant in certain lots of antimony pentachloride. PCB perchlorinations with bromide-contaminated antimony pentachloride resulted in significant amounts of bromononachlorobiphenyl.
Known Addition Procedure for Determining Fluoride in Feeds with an Ion-Specific Electrode
Authors: Melton James R , Hoover William L , Ayers Jo Lynn 
Published: February 2020

Abstract
A know addition method for determining low levels of fluoride in feeds with a solid-state fluoride electrode is described. The feed samples are reacted with hydrochloric acid, and a concentrated citrate buffer is added to maintain ionic strength and pH. The amount of fluoride in the sample is calculated from the change in potential after the addition of fluoride standard. Any interferences by ions commonly found in feeds are minimized by the known addition technique. The described method is rapid and precise, and results compare favorably with those from the AOAC method for fluoride, 25.029-25.035.
Microbiological Assay of Nystatin in Feeds
Authors: Platt Thomas B , Itkin Arthur G 
Published: February 2020

Abstract
A modification of the official method for nystatin in feeds was collaboratively studied. Feed is extracted into methanol and a portion of the extract is converted to a feed blank by heating 20 min at 121°C. The remaining portion of the extract is assayed vs. the standard curve prepared in feed blank. Four commercial poultry laying mashes were studied; 2 were tested as formulated, 2 were tested in both crumble and powder form, and 1 of the ground feeds was diluted with cornmeal. Each sample was prepared to contain ca 50 and 100 g nystatin/ ton. Each of 9 collaborators analyzed, in duplicate, 3 different samples. The theoretical nystatin content was established by the collaborators' assay of the premix used to prepare the samples. Recoveries of activity averaged 97.6% for the lower concentration and 100.4% for the higher concentration. The method was adopted as official first action to replace the present official first action method for feeds containing ≥ 50 g nystatin/ton, 38.200-38.203.
Rapid Spectrophotometric Method for Direct Available P2O5 in Fertilizer
Authors: Thorpe Virginia A 
Published: February 2020

Abstract
In the rapid spectrophotometry method described, direct available P2O5 in fertilizer is determined in the presence of ammonium citrate, meta- and polyphosphates are hydrolyzed with a simple heating step, and coloring matter (other than organic material) is destroyed with the direct addition of HN03. Direct available extracts prepared from samples containing organic phosphorus can be effectively digested by a simple technique of heating an aliquot with acid in a special decomposition vessel. The method is rapid, accurate, and precise and would be readily adapted to automated techniques.
Gas-Liquid Chromatographic Determination of Methanol, Ethanol, and Isopropanol in Cosmetics, Using the Headspace Analytical Technique
Authors: Paulus Grant Geordie L 
Published: February 2020

Abstract
Methanol, ethanol, and isopropanol were determined in cosmetics by the gas chromatographic analysis of the vapors in the air space above a diluted sample. This method of headspace sampling compares favorably with other methods of determining alcohols, such as direct injection and isolation by codistillation. It is not necessary to isolate the alcohols before analysis because the method avoids the injection of nonvolatile substances in the sample, which may be detrimental to the column or the detector. The determination was carried out on a 6' × ¼" column packed with Chromosorb 101 coated with 1 % Ethomeen 18/60. An appropriate internal standard is used for the analysis of each alcohol to compensate for possible errors introduced by headspace sampling. The technique is applicable to various types of cosmetic products and is useful for the analysis of samples containing as little as 0.5% alcohol.
Determination and Confirmation of Hexachlorobenzene in Fatty Samples in the Presence of Other Residual Halogenated Hydrocarbon Pesticides and Poly chlorinated Biphenyls
Authors: Van Hove Holdrinet Micheline 
Published: February 2020

Abstract
Hexachlorobenzene (HCB) determination and confirmation at low residual levels (parts per billion range) is hampered by the presence of electron-capturing co-extractives, other organochlorine pesticides, and polychlorinated biphenyls (PCBs). A method is described to routinely examine lipid material for residual HCB, using a column chromatographic separation system and subsequent derivatization. Following initial extraction and cleanup, organochlorines, PCBs, and HCB are successively eluted from a charcoal column. After gas chromatographic analysis of each of the fractions, the HCB fraction is subjected to caustic alkali at high temperatures, and the hydrolyzed product is methylated to yield the pentachlorophenol methyl ether derivative.
Microcoulometric Determination of Organochlorine Pesticides in Human Blood
Authors: Griffith Francis D , Blanke Robert V 
Published: February 2020

Abstract
Improvements in the microcoulometric halogen system allow analysis of as little as 1 ppb chlorinated pesticides with specificity and linearity. Modifications were made in the sulfuric acid method of extracting pesticides from human whole blood to obtain recovery of 24 pesticides and 7 industrial chemicals. Recovery data were tabulated. Retention time and response tables for OV-210 and SE-30/QF-1 columns were prepared for these compounds, using the microcoulometric detector.
Extraction of Chlorinated Hydrocarbon Insecticides from Soil: Collaborative Study
Authors: Woolson Edwin A 
Published: February 2020

Abstract
Soil premoistened with 0.2M NH4C1 was shaken with hexane-acetone (1+1) to extract chlorinated hydrocarbon insecticides. Standard AOAC methods (29.014 and 29.017) were used for cleanup and detection of residues in the extract. Seven laboratories analyzed 3 soil unknown samples which contained 6 added insecticides each (at a range of 0.24 to 6.18 ppm) and a spike-and-recovery sample which contained 10 insecticides. Recovery from the spiked sample averaged 9 1% (86-100%) of the added insecticides, with an average coefficient of variation of 13.54%. Recovery from the 3 unknown samples averaged 88% (69-118%) with a coefficient of variation of 12.84%. The method has been adopted as official first action.
Sensitivity of Brine Shrimp (Artemia salina) to Trichothecenes
Authors: Eppley Robert M 
Published: February 2020

Abstract
Brine shrimp larvae have been successfully used as a biological monitoring system in the isolation of 5 naturally occurring, toxic 12,13- epoxy-Δ9-trichothecenes. A simplified procedure is described for the biological confirmation of these mycotoxins. The sensitivity of the brine shrimp test described for detecting 10 of the naturally occurring 12,13-epoxy-Δ9-trichothecenes is approximately 0.04—0.4 μg/ml.
Ammoniation of Aflatoxin B1: Isolation and Identification of the Major Reaction Product
Authors: Lee Louise S , Stanley James B , Cucullu Alva F , Pons Walter A , Goldblatt Leo A 
Published: February 2020

Abstract
The major product formed from reacting pure aflatoxin B1 with ammonium hydroxide at 100°C under pressure was isolated in crystalline form. The compound, molecular weight 286 (mass spectra), ultraviolet (UV) absorption, λMe0H 227, 324 nm (ε 15,920, 12,440), is nonfluorescent, exhibits phenolic properties, and lacks the lactone group characteristic of aflatoxin B1. Acidification of the compound did not regenerate aflatoxin B^ Calculations made from UV absorption spectra indicate that this molecular weight 286 compound comprises about 30% of the crude ammoniation product. It is postulated that the new product, C16H14O5, arises from opening the lactone ring of aflatoxin B1 during ammoniation, formation of the ammonium salt of the resultant hydroxy acid, and loss of carbon dioxide from this β-keto acid. Because this compound arises from decarboxylation, the trivial name aflatoxin D1 is proposed.
Collaborative Study for the Development of Latent Fingerprints on a Nonporous Surface, Using Standard Brushing Method for Powders
Authors: Connor Charles M 
Published: February 2020

Abstract
Eight latent fingerprint experts participated in a collaborative study of the black powder brushing method for the development of latent fingerprints. Latent images were placed on glass slides by the examiner, using both male and female subjects. The standard brush method, using black powder provided by the Associate Referee, was used to develop the fingerprints. Conclusive results were obtained; 138 of the 144 images (95.8% ) were considered suitable for identification purposes. The method has been adopted as official first action.
Microscopical Characterization of Glass Fragments
Authors: McCrone Walter C 
Published: February 2020

Abstract
Two collaborative studies have been completed and the method for characterizing glass fragments has been finalized. Using a monochromator, hot stage apparatus, and standard liquids of known refractive index, dispersion and dn/dT matching wavelengths were measured over an appropriate range of known temperatures. Results from the second collaborative study were greatly improved over those from the first study and showed that refractive indices of a small glass fragment can be measured to within ±0.0001. This is smaller than the variation observed within most glass objects. The revised method has been adopted as official final action (suspension of the rules).
Simplified Modifications of the AOAC Method for Bacteriostatic Activity of Laundry Additives
Authors: Wilson Frederic H , Brown Claude P , Ball William 
Published: February 2020

Abstract
Modifications of the AOAC bacteriostatic activity of laundry additives method are described, which render it more economical and less time consuming. The arbitrary use of a minimum of 18—20 edges showing clear zones of inhibition of a test organism, when 5 fabric patches 1" square are used, is liable to misinterpretation, since faulty methods of introducing germicidal substances into fabric in the final rinse during laundering result in incomplete dispersion and uneven impregnation. Therefore, absence of a zone along more than 2 edges may indicate faulty impregnation rather than the degree of bacteriostatic activity. In the modified procedure, 5 circular fabric disks from samples submitted by laundries were used for each test. They were immersed in melted, seeded nutrient agar in 1 large Petri dish and incubated at 5 and 37°C. Clear zones completely around all 5 circumferences were chosen as the criteria for bacteriostatic activity. If all 5 disks, taken from different areas of the test sample, do not show complete inhibition, impregnation of the bacteriostat is not uniform.
Automated Chemical Determination of Methionine
Authors: Gehrke Charles W , Neuner Terry E 
Published: February 2020

Abstract
A rapid, accurate, and precise spectrophotometry method, based on the nitroprussidemethionine color reaction, has been developed for the determination of methionine in soybeans, mungbeans, and corn. Amino acid interference was eliminated by partial enzymatic hydrolysis of samples for 4 hr at 50 °C with papain; the samples were analyzed by an automated system. Precision and accuracy were determined by repeated independent analyses of 13 samples of corn, mungbeans, and soybeans; the data were compared to independent classical ion exchange amino acid results. The range for each set of samples varied from 0.02 to 0.04 w/w% methionine. The per cent recovery for 12 of the 13 samples compared to those from ion exchange ranged from 95.2 to 107.1% with an average of 100.2%. The standard deviation varied from 0.01 to 0.02, and the per cent relative standard deviation from 11.8% for a 0.16 w/w% sample to 2.5% for a 0.42 w/w% sample. Recovery of added methionine from corn samples ranged from 92.7 to 102.0% (96.8% average) ; from soybeans 95.0 to 112.0% (101.9% average); and from mungbeans 91.3 to 102.0% (95.8% average). A reliable automated method has been developed which is applicable to different types of biological substances; 20 samples/hr can be analyzed.
Collaborative Study of a New Method for the Extraction of Aphids, Thrips, Mites, and Flies from Frozen Green Leafy Vegetables
Authors: Miller Mary T 
Published: February 2020

Abstract
A method, which consisted of mixing various frozen green leafy vegetables with dilute sodium sulfate and mineral oil followed by flotation in a Wildman trap flask or Corning percolator, was tested by 12 collaborators. Satisfactory results were obtained and the method has been adopted as official first action.
Partition Chromatographic Method for Caffeine and Sodium Benzoate Injections
Authors: Weber John D 
Published: February 2020

Abstract
Sodium benzoate is retained on a Celite :1N sodium bicarbonate column while caffeine is eluted with ether and trapped on a second Celite: 1N H2S04 column. The sodium benzoate is recovered in the form of benzoic acid by elution with acetic acid in chloroform and the caffeine is eluted with chloroform. The concentrations in the eluates are directly measured by ultraviolet spectrophotometry.
Total Flavonoid and Rutin Content of the Different Organs of Sophora japonica L.
Authors: Balbaa Shafik I , Zaki Ashgan Y , El Shamy Ali M 
Published: February 2020

Abstract
The total flavonoid content of the flowers, fruits, leaves, and small branches of Sophora japonica L. was determined colorimetrically after addition of 0.lM aqueous aluminum chloride. The total flavonoid and isoflavonoid content of the fruits was determined gravimetrically. Rutin was separated by thin layer chromatography from the different organs, and determined either densitometrically or spectrophotometrically, using a modified elution technique. Rutin was recovered almost completely with an average loss of 2.5%. The percentages of flavonoids and rutin of the flower buds, pericarps, seeds, leaflets, and small branches were 24.29 and 23.5, 10.57 and 4.3, 1.75 and 0.55, 6.63 and 4.7, and 1.5 and 0.26, respectively, while the total flavonoid and isoflavonoid content of the fruits was 43%.
Modification of the AOAC Qualitative Test for the Determination of Fish Oils and Marine Oils
Authors: Schwien William G 
Published: February 2020

Abstract
The current AOAC test for the detection of fish oil in vegetable oils, 28.098, can be readily modified through the use of diluted bromine solution and Wijs solution. This modification allows the precipitation of octabromides, which is indicative of the presence of fish oils, to be observed more clearly. Since the precipitate can be measured, the test can be semiquantitative when known fish oil mixtures are treated in a like manner. This modification has been adopted to replace 28.098.
Estimation of Butylated Hydroxyanisole and Butylated Hydroxytoluene in Meat Products
Authors: Singh Joginder , Lapointe Michel R 
Published: February 2020

Abstract
A procedure is described for the estimation of butylated hydroxyanisole and butylated hydroxytoluene in meat products. It involves direct extraction of the antioxidants from the meat products by using acetonitrile as the solvent in a steel ball mill. Cleanup is carried out on a column of deactivated acidic alumina. Gas chromatography with a flame ionization detector is used for qualitative and quantitative determination of the antioxidants. Average recoveries of antioxidants added to 10 g samples of corned beef and sausages ranged from 61 to 90%.
Collaborative Study of the Gas-Liquid Chromatographic Determination of Indole in Shrimp
Authors: Staruszkiewicz Walter F 
Published: February 2020

Abstract
A new gas-liquid chromatographic (GLC) method for the determination of indole in decomposed shrimp was submitted to collaborative study. Five samples of shrimp were analyzed in duplicate by the collaborators. The samples included passable and decomposed frozen raw shrimp and also decomposed shrimp that had been cooked and freeze-dried. The levels of indole in the samples ranged from 0 to approximately 110 μg indole/100 g shrimp. No indole was found in any of the passable samples by any collaborator. The amounts of indole found in the decomposed samples were approximately 14, 24, and 115 μg indole/100 g shrimp. The collaborators recovered an average of 106% of the indole which had been added to a sample of passable shrimp. A set of samples was analyzed by the present AOAC colorimetric method for comparison. The GLC method will also detect 3-methylindole (skatole). The method has been adopted as official first action.
Aflatoxin M1: Analysis in Dairy Products and Distribution in Dairy Foods Made from Artificially Contaminated Milk
Authors: Stubblefield Robert D , Shannon Gail M 
Published: February 2020

Abstract
A published method to determine aflatoxin M1 in fluid and concentrated milks was refined to permit assays of a wider range of dairy products. Milk products that were spiked with aflatoxin Mx were processed with commercial dairy cultures, rennet, and organic acids to make several cheeses and butter. Cheeses that were representative of various curd-precipitation methods or high cooking temperatures were included. When milk was set with lactic acid cultures and small quantities of rennet to produce short-set cottage cheese or heated with lactic acid starter to prepare ricotta cheese, about 71–74% of the aflatoxin M1 was recovered in the whey fractions. Nearly equal quantities of M1 were detected in curds and whey from long-set, acidprecipitated cottage cheese and from rennetprecipitated cheeses, such as colby, cheddar, and swiss. Results were similar with queso bianco cheese products that were produced by direct addition of organic acids. According to analysis, only 16% of the available M1 was in the butter while the remainder was in the buttermilk.
Dose Response Score of AOAC Use-Dilution Test for Quality Control of Internal Standard and Products
Authors: Walter George R , Scheusner Dale L 
Published: February 2020

Abstract
Disinfectant products registered with the Environmental Protection Agency require efficacy substantiation by the AOAC use-dilution test. This test has a low binomial probability associated with failures in the procedure. An alternative means of recording the use-dilution test response is proposed. In it a score is presented in a form which may be treated as a continuous measurement and sequentially plotted to form a control chart showing the upper and lower control limits for a given organism.
Leuco Base Determination in the Triphenylmethane Dyes, FD&C Blue No. 1, FD&C Green No. 3, and FD&C Violet No. 1
Authors: Dantzman John , Stein Charles 
Published: February 2020

Abstract
The quantitative oxidation of leuco bases in FD&C triphenylmethane dyes was examined. A spectrophotometric method for determining the amount of leuco base, using molecular oxygen in the presence of cupric chloride, was studied. Leuco base recovery was found to be 90.0–103% for FD&C Blue No. 1, 97.2-101.9% for FD&C Green No. 3, and 95.4-100% for FD&C Violet No. 1.
Analysis of Carbamate and Urea Herbicides in Foods, Using Fluorogenic Labeling
Authors: Lawrence James F , Laver Gary W 
Published: February 2020

Abstract
A procedure using fluorogenic labeling for the analysis of carbamate and urea herbicides in several food types has been developed. Extracted herbicides are hydrolyzed to their corresponding anilines, which are then labeled with dansyl chloride (1-dimethylaminonaphthalene- 5-sulfonyl chloride). The reaction is carried out on a thin layer plate which is subsequently developed, and the separated spots are either scanned for fluorescence or are removed from the layer and quantitatively analyzed in solution by fluorometry. As low as 0.05 ppm herbicide can be detected with no interference from coextractives. Other than a single partition step from the extracting solvent no cleanup is required. The method may be used for confirmation of the identity of a number of carbamate and urea herbicides, as a quantitative analytical technique where equipment is available, or as a method for screening where only the knowledge of herbicide presence is required.
Estimation of Malaoxon in the Presence of Malathion by the Ferric Hydroxamate Method
Authors: Bhagwat Vasanti M , Ramachandran Bhikshander V 
Published: February 2020

Abstract
Both malathion and malaoxon are completely extractable from aqueous suspensions by benzene- isobutanol (1 + 1). Aliquots of the extract are evaporated at 110– 120°C, the residue is dissolved in methanol, and the total ferric hydroxamate color is determined. Extraction of a second aliquot with cyclohexane removes malathion and some malaoxon. Malaoxon is selectively partitioned from cyclohexane into alkaline hydroxylamine, leaving only malathion in the cyclohexane phase. After the cyclohexane phase is evaporated, the amount of malathion can be estimated by the ferric hydroxamate method. The difference in the color for the benzene-isobutanol extract and the cyclohexane extract represents that due to malaoxon; the amount of malaoxon may be calculated from a standard curve. The method, sensitive to about 0.2 μmole malaoxon, is useful for monitoring the laboratory preparation of malaoxon from malathion.
Chemical Ionization Mass Spectrometry of Organophosphorus Insecticides
Authors: Holmstead Roy L , Casida John E 
Published: February 2020

Abstract
The chemical ionization (CI) mass spectra of 15 important organophosphorus insecticides and 14 of their major metabolites are discussed in relation to the effect of chemical structure on fragmentation patterns. The fragments obtained with CI are sometimes quite different from those formed on electron impact and, in general, simpler spectra are obtained with CI.
Systematic Approach to the Detection of Explosive Residues. III. Commercial Dynamite
Authors: Midkiff Charles R , Washington Willard D 
Published: February 2020

Abstract
Tests are described for the detection and identification of suspected dynamite in bombing debris. A discussion of major categories and typical formulations of dynamite is included. Thin layer chromatographic and infrared techniques are utilized for the identification of the explosive oils nitroglycerin and ethylene glycol dinitrate, which are present in most commercial dynamites. Problems encountered with solvent extraction of these oils are discussed. Additional chemical tests performed on the debris to facilitate identification of the particular type of dynamite present in the debris are described.