bluuebunny/crossref_metadata_2025_split huggingface dataset:
Transfer of Reports from an Automated Gas Chromatographic System to a Large Computer for Final Processing
Authors: Clower Marion 
Published: February 2020

Abstract
An automated gas chromatographic system consisting of a Hewlett-Packard 5710 gas chromatograph, a Varian 8000 autosampler, and a Spectra-Physics 4000 laboratory data system has been interfaced to FDA's large, central computer facility by using a Tektronix 4923-01 digital cartridge tape recorder. The autosampler provides single or multiple injections of up to 60 samples. The data system is preprogrammed with appropriate sample and standard information in addition to parameters for proper peak integration. A chromatogram is traced and a report of integration area counts for each peak detected is prepared by the data system after each chromatographic analysis. A duplicate of each report is recorded on the data cartridge. After analysis of all samples, the quality of chromatography is examined for acceptability. The chromatographic reports contained on the data cartridge may then be entered into the computer via a terminal equipped with a similar digital cartridge tape recorder. Translation of the reports, correlation of responses from sample and standard solutions, all calculations, and a complete report of each sample analysis are obtained by using the computer programming language APL. The data system-cartridge tape recorder interface, as well as data reduction using the large computer, is discussed.
Volatile Organic Compounds in Water at Thirty Canadian Potable Water Treatment Facilities
Authors: Otson Rein , Williams David T , Bothwell Peter D 
Published: February 2020

Abstract
A static headspace technique and previously developed and evaluated dynamic headspace and liquid-liquid extraction techniques were applied in a survey of volatile organic compounds in water at 30 Canadian potable water treatment facilities. Of the 43 compounds investigated, 27 compounds were detected in the water samples. Chloroform and bromodichloromethane occurred most frequently in treated water, and trichloroethylene, tetrachloroethylene, 1,2-dichloroethane, dichloromethane, benzene, toluene, ethylbenzene, and the xylenes occurred frequently in both treated and raw water. Only chloroform occurred frequently at levels above 10 μg/L in treated water. Generally, higher levels of organic compounds were found during August-September than during November-December.
Gas-Liquid Chromatographic Derivatization and Chromatography of N-Methylcarbamate Methoxy Derivatives Formed with Trimethylanilinium Hydroxide
Authors: Ogierman Leonard 
Published: February 2020

Abstract
Carbamate insecticides injected into a gas-liquid chromatograph react with trimethylanilinium hydroxide to give derivatives that have good gas-liquid chromatographic properties. The substituted phenyl N-methylcarbamates give methoxy derivatives by this procedure. Chromatographic response was linear with increased concentration for the synthetic standard and the on-column methylation products of the examined substances. The standards obtained were identified by ultraviolet and infrared absorption spectroscopy, as well as by nuclear magnetic resonance and mass spectral analysis.
Infant Formula Physical Stability
Authors: Miles J Preston 
Published: February 2020

Abstract
The physical nature of liquid infant formula products is characterized in terms of emulsion, suspension, and solution processes. Such mixtures inevitably undergo phase separation. A variety of physical and chemical phenomena govern the gradual changes in the appearance of these products. The consequent loss of physical elegance is primarily a question of consumer acceptance. Only in the most extreme cases do the physical characteristics deteriorate to the point that swallowing and digestion are affected. Recently, both public and regulatory attention has been focused on the physical characteristics of liquid infant formula products. Formula appearance is the product aspect most readily evaluated by the consumer. The design and manufacture of products that will have consistent appearance over extended periods is a difficult technical problem. This presentation summarizes the phenomena responsible for changes in the physical characteristics of liquid infant formula products. Product defects are discussed and methods for product evaluation are described. Representative data on the effect of storage on product physical elegance also are presented.
Survival and Movement of Clostridium perfringens in Sewage-Treated Soil
Authors: John WILLIAM D S T , Matches Jack R 
Published: February 2020

Abstract
The survival and movement of Clostridium perfringens in soil were studied. Fresh dewatered sewage sludge was added to 2 plots of tilled soil. During analyses for 24 weeks, some movement of spores from surface sludge into soil was obtained but little movement through the soil took place. In laboratory studies, columns of soil with a surface layer of sludge were subjected to the equivalence of 67 in. of rain. During this treatment, slow movement through the soil was obtained, but organisms were not detected in column effluents. These data show that C. perfringens will survive for at least 24 weeks in soil, with little movement. The application of sewage sludge increases the total numbers of C. perfringens in soil, but should have little effect on food poisoning from foods grown in treated soil.
High Pressure Liquid Chromatographic Determination of Zearalenone in Chicken Tissues
Authors: Turner G Vincent , Phillips Timothy D , Heidelbaugh Norman D , Russell Leon H 
Published: February 2020

Abstract
A method is reported for the extraction and analysis of zearalenone in chicken fat, heart muscle, and kidney tissue by using high pressure liquid chromatography (HPLC). Zearalenone is extracted with acetonitrile, cleaned up with hexane, and extracted further with ethyl acetate. Zearalenone is determined by HPLC using a reverse phase radial compression separation system, an ultraviolet absorbance detector, and a mobile phase of acetonitrile-water (60 + 40) (v/v). Recoveries of zearalenone added at levels from 50 to 200 ng/g are in the range 82.6-95.1%.
Colorimetric Determination of Propoxur and Its Residues in Vegetables
Authors: Appaiah Kalapanda M , Kapur Omprakash , Nagaraja Krishnarajpet V 
Published: February 2020

Abstract
A method has been developed for the determination of propoxur (o-isopropoxyphenyl N-methylcarbamate) based on the hydrolysis of propoxur with methanolic potassium hydroxide to its phenol and coupling with diazotized 4,4-diaminodiphenyl sulfone. The orange complex formed has an absorption maximum at 500 nm and obeys Beer’s law in the range 0.25-5.0 μg/mL. The method can be applied to levels as low as 0.5 ppm propoxur from vegetables.
Improved Method for Determination and Identification of Serotonin in Foods
Authors: García-Moreno Concepcion , Rivas-Gonzalo Julian C , Peña-Egido M Jesus , Mariné-Font Abel 
Published: February 2020

Abstract
A previously described method to identify and quantitate serotonin in foods has been improved. The extraction and separation of serotonin from interfering substances has been improved, and the scope of material to which the method may be applied has been widened. The relative standard deviation (RSD) for repeated determinations of serotonin in canned fried tomato puree and the average recovery of serotonin added to the same sample was 6.25 and 89.9%, respectively. The method showed the presence of serotonin in apricots, cherries, and peaches
Selected Ion Mass Spectrometric Identification of Chlorophenol Residues in Human Urine
Authors: Hargesheimer Erika E , Coutts Ronald T 
Published: February 2020

Abstract
A method is presented for the detection and confirmation of trace chlorophenol residues in environmental and biological samples by mass spectrometry with selected ion monitoring (SIM). Propionate and acetate ester derivatives of phenol, cresols, mono-, di-, tri-, and tetrachlorophenols, pentachlorophenol, as well as the internal standard 4,6-dibromo-o-cresol, were prepared directly in aqueous solution, using the appropriate anhydride reagent. The acetate or propionate esters were quantitatively extracted and then separated by gas-liquid chromatography using either an SP-1240DA or OV-101 packed column. Electron impact SIM was carried out by simultaneously monitoring up to 4 diagnostic fragment ions of each chlorinated phenol. The use of SIM eliminated background interference encountered using flame ionization or electron capture detectors, and allowed identification of chlorophenol residues in extracts of urine samples collected from individuals without known exposure to chlorophenols. Phenol concentrations as low as 1.0 pmol/mL urine gave peaks that were readily discernible by SIM.
Optimum Conditions for Hydride Generation of Selenium and Its Determination by Atomic Absorption Spectrophotometry
Authors: Brooks Robert R , Willis Janine A , Liddle John R 
Published: February 2020

Abstract
Instrumental parameters and other variables were studied to establish the optimum indicators for determination of selenium by atomic absorption spectrophotometry using the hydride generation procedure with cold-trapping. Optimum conditions were established by consideration of the following variables: volume of reaction solution, acid concentration in the reaction mixture, lapse of time after last addition of borohydride, method of addition of borohydride, carrier gas flow rates, position of source beam in the flame cell, oxidation state of selenium, and effect of drying the cold trap between successive determinations. This latter procedure greatly improved the reproducibility of the technique (from ±28% to ±2%. The limit of detection was about 2 ng selenium.
Determination of Penicillin G, Ampicillin, and Cephapirin Residues in Tissues
Authors: Vilim Arnost B , Larocque Lyse 
Published: February 2020

Abstract
A cylinder plate microbiological method was developed for the rapid, quantitative determination of penicillin G, ampicillin, and cephapirin in animal tissues. The method uses agar plates seeded with stable spores of Bacillus stearothermophilus var. calidolactis and incubated 4 h at 64°C. Standard curves were obtained for the following ranges of concentration of antibiotics in tissues: 0.02-0.32 IU penicillin G/g, 0.0125-0.2 μg ampicillin/g, and 0.02-0.32 μg cephapirin/g. The proposed method is suitable not only for penicillin residue analysis, for which the sensitivity has been greatly improved compared with the Sarcina lutea method, but also for depletion studies on these antibiotics, which are commonly used to treat diseases in food-producing animals.
Turbidimetric Assay of Penicillin in Feeds: Addition of Magnesium Sulfate to Eliminate Chlortetracycline Interference
Authors: Chiang Tom , Hanks Alan R , Melton James R , Hoover William L 
Published: February 2020

Abstract
The official AOAC method for extracting penicillin from feeds allows some chlortetracycline to be coextracted if the latter is also present in the sample. This can cause a high bias in results obtained by using the turbidimetric assay in which the test organism is sensitive to both antibiotics. In this report, we show that magnesium ions can be used to circumvent the interference of chlortetracycline in the turbidimetric assay for penicillin.
Treatment of Freshly Harvested 1980 Georgia Dent Corn Samples Collected for Aflatoxin Analysis
Authors: Shotwell Odette L , Bennett Glenn A , Kwolek William F , Hesseltine Clifford W 
Published: February 2020

Abstract
In 1980, corn was harvested from six 15-ft rows in each of 67 fields in Georgia for aflatoxin analysis. Every sixth ear from each field was placed in a sample bag to be dried the day of collection. The rest of the corn was husked and shipped to Peoria in cardboard boxes. When undried ear samples arrived in Peoria, each sample was randomly separated into 5 equivalent subsamples. One set of 67 subsamples was shelled and dried as soon as possible to avoid further aflatoxin formation. Two other sets of 67 subsamples were stored 3 and 6 weeks before shelling and drying. The remaining 2 sets of ear samples were placed in plastic bags with 5% Monoprop (1 part propionic acid plus 1 part versite) and stored 3 and 6 weeks before shelling and drying. The samples dried in Georgia before shipping had an average total aflatoxin level of 217 ng/g. Samples shelled and dried immediately after arrival had an average level of 202 ng/g. Samples shelled and dried after 3 and 6 weeks of storage had average total aflatoxin levels of 417 and 387 ng/g, respectively. Samples stored 3 and 6 weeks in the presence of 5% Monoprop (2.5% propionic acid) had average total aflatoxin levels of 120 and 157 ng/g, respectively.
High Performance Liquid Chromatographic Determination of Nonvolatile Phenolic Compounds in Matured Distilled Alcoholic Beverages
Authors: Lehtonen Matti 
Published: February 2020

Abstract
Gallic acid, vanillic acid, syringic acid, vanillin, syringaldehyde, and ferulic acid were determined in matured spirits by reverse phase high performance liquid chromatography. Concentrations varied from 0 to 11 ppm depending on the compound and the beverage. Gallic acid and syringaldehyde were the main components. Vanillic acid, vanillin, and, especially, gallic acid were the most important in distinguishing the different classes of spirit. Discriminate analysis gave 2 factors, which, however, could not be used to classify the samples with any great confidence: 61% of the whiskies, 33% of the rums, and 52% of the brandies were correctly assigned in this way.
Nitro Musk Fragrances as Potential Contaminants in Pesticide Residue Analysis
Authors: Yurawecz Martin P , Puma Bart J 
Published: February 2020

Abstract
Synthetic nitro musks, fragrance ingredients of soaps, lotions, and other products commonly used in the home and laboratory, are potential interferences in analyses of foods for pesticide residues. These fragrances are recovered by extraction-cleanup procedures of the AOAC multiresidue method for fatty and nonfatty foods and have electron capture gas-liquid chromatographic properties similar to the organochlorine residues for which the method has official status. This report presents the analytical evidence that led to the identification of musk xylol (1-[1,1-dimethylethyl]-3,5-dimethyl-2,4,6-trinitrobenzene) as a contaminant in a sample of fish; mass spectra and data on the behavior in the AOAC multiresidue method of musk xylol, musk ambrette (1-[1,1-dimethylethyl]-2-methoxy-4-methyl - 3,5 - dinitrobenzene), musk tibetene (1-[1,1-dimethylethyl]-3,4,5-trimethyl-2,6-dinitrobenzene), and musk ketone (1-[4-(1,1-dimethylethyl)-2,6-dimethyl - 3,5 - dinitrophenyl] ethanone); and information on some sources of these chemicals in the laboratory environment.
Gas-Liquid Chromatographic Determination of Trace Amounts of Nitrite in Egg, Egg White, and Egg Yolk
Authors: Tanaka Akio , Nose Norihide , Masaki Hiroyuki , Kikuchi Yoshinori , Iwasaki Hisao 
Published: February 2020

Abstract
A simple, sensitive, and practical method is described for determination of nitrite in egg, egg white, and egg yolk. Egg is deproteinized by adding a mixture of ammonium thiocyanate, mercuric chloride, and zinc acetate, and centrifuged. Nitrite in the supernate is converted to tetrazolophthalazine by reaction with hydralazine in acidic solution and then determined by gas-liquid chromatography with an electroncapture detector (GLC-ECD) and a column of OV-225 on Chromosorb W(HP). Nitrite concentrations from 5 to 50 ng/mL are calculated from peak height; the detection limit is 3 ng/mL extract. Recoveries from eggs, egg whites, and egg yolks ranged from 91.7 to 98.0%. The mean nitrite concentration in 50 egg samples was 0.04 ppm (0.01-0.11 ppm) with a detection limit of 4 ng nitrite/g.
Diagnosis of Ethylene Glycol (Antifreeze) Intoxication in Dogs by Determination of Glycolic Acid in Serum and Urine with High Pressure Liquid Chromatography and Gas Chromatography-Mass Spectrometry
Authors: Hewlett Tracy P , Ray Allen C , Reagor John C 
Published: February 2020

Abstract
A relatively fast and sensitive high pressure liquid chromatographic (HPLC) and gas chromatographicmass spectrometric (GC/MS) method was developed for determination of glycolic acid, one of the major metabolites of ethylene glycol, in extracts of canine urine and serum. The procedure involves extraction of glycolic acid with methyl ethyl ketone and derivatization with O-p-nitrobenzyl-N,N'-diisopropylisourea (PNBDI) in ethyl acetate solution. Recovery was greater than 94% from spiked samples. Ethylene glycol and commercial antifreeze were administered to experimental dogs at different dosage levels to reproduce the naturally occurring toxicosis associated with the consumption of commercial antifreeze. Glycolic acid was determined in either the urine or serum or both from these dogs by HPLC and GC/MS. 1,3-Butanediol, a competitive inhibitor of ethylene glycol biotransformation, was administered to one dog concurrently with antifreeze. In that experiment, it was effective in decreasing glycolic acid formation and prevented acute metabolic acidosis, kidney damage, and death.
Evaluation of Urea-Acid System as Medium of Extraction for the B-Group Vitamins. Part II. Simplified Semi-Automated Chemical Analysis for Niacin and Niacinamide in Cereal Products
Authors: Roy Ram B , Merten John J 
Published: February 2020

Abstract
Efficiency of a urea-acid system was evaluated as medium of extraction for niacin and niacinamide from cereals and other selected food products. Samples were treated with IN HC1 in the presence of urea and autoclaved 30 min at 15 psi. Extracts were diluted to a known volume, filtered, and analyzed. The analytical results obtained for niacin were compared with values obtained by AOAC method 43.044. In general, the urea-acid extraction system was simple and straightforward with an efficiency comparable to the AOAC method. The analytical manifold designed uses fewer modules, gives net absorbance readings from sample and blank, and is capable of analyzing 50 samples per hour.
High Performance Liquid Chromatographic Determination of Malondialdehyde in Vegetable Oils
Authors: Hirayama Teruhisa , Yamada Naohide , Nohara Motoshi , Fukui Shozo 
Published: February 2020

Abstract
A simple high performance liquid chromatographic (HPLC) method has been developed for determining malondialdehyde (MDA) in vegetable oils. MDA was reacted with dansyl hydrazine in an acidic medium, and the product, 1-dansyl-pyrazole, was determined by HPLC, using a Zorbax sil column with mixed mobile phase of n-hexane-methylene chloride. MDA can be determined as 1-dansyl-pyrazole by f luorometric detection at a level of 0.01 ppm in vegetable oils.
Automated Analysis of Flour Extracts for Uric Acid and Its Correlation With Degree of Insect Defilement
Authors: Galacci Raymond R 
Published: February 2020

Abstract
An automated method is described for quantitating uric acid in a sodium acetate extract of flour. The difference in color intensity developed in a flour extract treated with the enzyme uricase and one that is not treated is measured spectrophotometrically. A mean recovery of 97.1% was obtained for 50 g flour samples spiked with 1 mg uric acid. The method can measure as little as 50 ng uric acid in 50 g flour and is used to establish a correlation between the uric acid in the flour and the number of insect fragments and excreta pellets present. A 42-data point least squares straight line having a slope of 1.62 and a correlation coefficient of 0.750 (99.9-100% valid) is used to establish the relationship of uric acid to insect defilement.
Ion-Pair High Performance Liquid Chromatographic Determination of Inosinic Acid in Meat
Authors: Kitada Yoshimi , Inoue Masashige , Tamase Kikuo , Imou Masako , Hasuike Akikazu , Sasaki Michiko , Tanigawa Kaoru 
Published: February 2020

Abstract
An ion-pair high performance liquid chromatographic (HPLC) technique is described for the determination of inosinic acid (IMP) in meat. The compound was extracted with perchloric acid and analyzed without cleanup. IMP is effectively separated, identified, and quantitated by using a reverse phase column, with ultraviolet detection. A C8 stationary phase and tetrabutyl ammonium as counter ion are used. Recovery of IMP added to meat at 500 or 2500 ppm levels was more than 95%; the limit of detection for IMP is 50 ppm.
Capillary Gas Chromatographic-Mass Spectrometric Determination of Individual Chlorobiphenyls in Technical Aroclors
Authors: Tuinstra Louis G M T H , Traag Wim A 
Published: February 2020

Abstract
Six technical Aroclors were separated into individual chlorobiphenyls on fused silica capillary columns. Fifty-three chlorobiphenyl standards were used to ascertain structures of a number of compounds in the technical mixtures by mass spectrometry. Results are compared with reports in the literature. Percentages of identified compounds are given, and the presence of unidentified chlorobiphenyls is indicated by the number of chlorine atoms, in order of compound elution from the column.
Reverse Phase Radial Compression High Performance Liquid Chromatographic Determination of Rotenone in Formulations
Authors: Bushway Rodney J 
Published: February 2020

Abstract
This paper describes a reverse phase radial compression high performance liquid chromatographic (HPLC) method to determine rotenone in pesticide formulations. Formulations are extracted in dioxane by gentle swirling while sonicating for 5 min. A 10 μL aliquot is injected into the HPLC system equipped with a radial compression unit (Z module) containing a μBondapak C18 Radial-Pak column. The mobile phase is acetonitrile-methanol-tetrahydrofuranwater (34 + 30 + 1 + 35). Rotenone is monitored at 280 nm. Retention time for rotenone is approximately 7 min with total analysis time of 20 min. For 5 different products analyzed 11 times each, the percent coefficients of variation were all below 1.65. No interferences from 11 other rotenoids and 8 pesticides which are sometimes formulated with rotenone were observed.
High Pressure Liquid Chromatographic Determination of Impurity Phenols in Technical 2,4-D Acid and 2,4-Dichlorophenol
Authors: Cochrane William P , Lanouette Monique , Singh Joginder 
Published: February 2020

Abstract
Thirteen technical 2,4-dichlorophenoxyacetic (2,4-D) acid and five 2,4-dichlorophenol (2,4-DCP) samples were obtained from several manufacturers and analyzed for the presence of various chlorinated phenolic impurities. Reverse phase high pressure liquid chromatography with a UV detector in series with an electrochemical detector was used for qualitative and quantitative determinations. Three solvent systems were investigated in the present study. The retention times obtained for various mono-, di-, and tri-chlorophenols with each solvent system are presented. The presence of ortho- and para-monochlorophenol (averages 1.23 and 0.41%, respectively), 2,6-dichlorophenol (average 4.5%), 2,4,6-trichlorophenol, and a dichloro-methyl phenol isomer were detected as contaminants in technical 2,4-DCP samples. Technical 2,4-D acid contained the same type of chlorophenol impurities but in much smaller amounts. A comparison of the sensitivity of a UV detector at 280 nm with an electrochemical detector showed the latter to be 5 to 15 times more sensitive, depending on the chlorophenol.