bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determination of Color in White Wine and White Grape Juice Using the White Wine Colorimeter
Authors: Wildenradt Herb L , Stafford Paul A 
Published: February 2020

Abstract
Further experience with the white wine colorimeter has demonstrated that this instrument provides a simple and reproducible method of color measurement for both finished and unfinished white wines and white grape juices. In view of the proven accuracy and utility of the white wine colorimeter, the method specifying this instrument, 11.B01–11.B02, has been adopted as official final action.
Collaborative Study of the Comparison of Mineral Wool Insulations in the Forensic Laboratory
Authors: Miller Elmer T 
Published: February 2020

Abstract
A method for the comparison of mineral wool insulation specimens was studied collaboratively. Exemplar and questioned specimens are compared microscopically for color of resin, shapes and quantity of slugs or shot, relative fiber diameters, and other gross characteristics. Then the resin is burned off, and the fibers are annealed at 500°C. The heat-treated fibers are compared for shortwave ultraviolet fluorescence, microscopic appearance, solubility in dilute and concentrated hydrochloric acid, and refraction and dispcrsion indices according to 45.002–5.007. Eight collaborators in 6 laboratories compared 8 matched pairs of large samples (such as exemplars) and small samples (such as might be found on a suspect’s clothing).
Preparation and Characterization of Aflatoxin B1-1-(O-carhoxymethyl) Oxime
Authors: Chu Fun S , Hsia M-T Stephen , Sun Piera S 
Published: February 2020

Abstract
A method is described for the preparation and purification of aflatoxin B1-1-(O-carboxymethyl) oxime from aflatoxin The overall yield was about 73–83%. The new aflatoxin B1, derivative was characterized by mass, ultraviolet, infrared, and nuclear magnetic resonance spectral analyses, and was nontoxic to 8-day-old chicken embryos when tested at a concentration of 3.48 μg/egg.
Collaborative Study Comparing the Spiral Plate and Aerobic Plate Count Methods
Authors: Gilchrist James E , Donnelly Cecil B , Peeler James T , Campbell Jeptha E 
Published: February 2020

Abstract
The spiral plate count method is a semiautomated plating technique that greatly reduces manpower and material costs normally associated with the pour plating technique. In this collaborative study, 8 laboratories compared the spiral and pour plating techniques, using 4 samples each of 3 products : frozen pumpkin pie, frozen chicken pot pie, and shampoo. The results show that 10 of the 12 comparisons of means of the pour and spiral methods were not significantly different; 2 values were significant at α = 0.01. Overall, the components of variance were less than that of the current milk standard, and the replicate per cent coefficient of variation was satisfactory. This study indicates that the spiral plate method is an acceptable alternative to the pour plate method; the spiral plate method has been adopted as official first action.
Dry Ash-Voltammetric Determination of Cadmium, Copper, Lead, and Zinc in Foods
Authors: Jones John W , Gajan Raymond J , Boyer Kenneth W , Fiorino John A 
Published: February 2020

Abstract
An analytical method is presented for determining cadmium, copper, and lead by differential pulse anodic stripping voltammetry and zinc by cathodic scan differential pulse voltammetry. Food samples are dry ashed using a sulfuric acid ashing aid, dissolved in dilute nitric acid, buffered at pH ~ 4.3 with an acetate buffer, and quantitatively analyzed using the technique of standard additions at a hanging mercury drop electrode. The quantitation limits (5 times the estimated detection limits) are approximately 5 ng/g for Cd, Cu, and Pb, and 50 ng/g for Zn. Accuracy of the method is established by (a) analysis of NBS Standard Reference Material No. 1577 Bovine Liver, (b) comparison of results obtained by the method described with those obtained by independent analytical methods, and (c) quantitative recovery of analyte metals from fortified, non-canned food samples. Results from an interlaboratory method trial indicate that the method is suitable for the analysis of a variety of food types.
Ruggedness Test for Ashing Methods in Feed: Comparison of Proposed Method of the International Organization for Standardization with AOAC Method
Authors: Torma Laszlo 
Published: February 2020

Abstract
A Youden ruggedness test was performed on the determination of ash in feeds to compare the proposed method of the International Organization for Standardization (ISO) with the official AOAC method. Three samples which contained low, medium, and high ash were analyzed. Six variables were studied : material of the ashing dishes, test portion, preliminary ashing, ashing temperature, ashing time, and additional ashing. Statistical evaluation of the ruggedness test indicated that for Sample A (5.41% average ash), the factors under study did not influence the ash recovery; for Sample B (10.84% average ash), changes in temperature influenced the ash recovery; and for Sample C (13.97% average ash), changes in preliminary ashing, temperature, and additional ashing appeared to influence the ash recovery. It is recommended that the composition of ash be studied further in order to evaluate the temperature and ashing time required to determine nutritionally valuable mineral content.
Collaborative Study of Accuracy and Precision of Rapid Determination of Fat in Meat and Meat Products by Foss-Let Method
Authors: Pettinati Julio D , Swift Clifton E 
Published: February 2020

Abstract
Collaborators in 12 meat and food industry laboratories performed 4 fat determinations each on 7 samples of meat and meat products by the rapid (7–10 min) Foss-Let method and compared the results with those obtained by AOAC method 24.005(a) or 24.005(b). From the overall mean of results on all samples, determinations by the Foss-Let method averaged 0.11% fat higher than by the AOAC method. This difference was not significant by the t-test (P = 0.05), which indicated agreement between the compared methods in determining fat content. Precision of the Foss-Let method was equivalent to and generally slightly better than that of the AOAC method. Standard deviations with the Foss-Let method were 0.2 % fat for between-duplicates and for within-laboratory repeatability; 0.4% fat for between-laboratories, including variation due to laboratory-sample interaction; and 0.5% fat for reproducibility between analysts in different laboratories. The Foss-Let method has been adopted as official first action.
Collaborative Study of Gas-Liquid Chromatographic Method for Analysis of Microencapsulated Methyl Parathion Insecticide
Authors: Karr James J 
Published: February 2020

Abstract
Eleven laboratories collaboratively studied the assay of methyl parathion in 2 formulations of Penncap-M insecticide. The procedure includes a grinding and extraction step, followed by the determination of methyl parathion by flame ionization gas-liquid chromatography. At the 15% level, the variance within laboratories was 0.0905, and among laboratories, 0.0755. At the 20% level, the figures were 0.0556 and 0.0205, respectively. The method has been adopted as official first action.
Gas-Liquid Chromatography of Bromoxynil Octanoate
Authors: Helfant Laurence J 
Published: February 2020

Abstract
A simple, direct method of analysis is proposed that will determine the weight percentage of bromoxynil octanoate in pesticide formulations. Using a gas chromatograph equipped with a flame ionization detector, the ester is separated from its isomers and other reaction by-products, and then quantitated by using an internal standard procedure. This method gives a specific percentage for bromoxynil octanoate, compared with halogen content derived from the Parr bomb procedure that is currently used.
Composition of Ammonium Nitrate-Urea-Water Fertilizer Solutions by Physical Measurements
Authors: Sloan Douglas M , Veales Ronald W 
Published: February 2020

Abstract
A simple method has been developed for determining the composition of fertilizer solutions containing ammonium nitrate, urea, and water. The specific gravity and refractive index are measured under controlled conditions and lines corresponding to these values are plotted on a triangle diagram. Composition is then read at the intercept, with a standard deviation &lt;0.25%, and total nitrogen is computed. The result varies from that obtained by chemical analysis by &lt;±0.25%.
Semiautomated Method for Total Nitrogen in Fertilizers
Authors: Wall Larry L , Gehrke Charles W 
Published: February 2020

Abstract
A semiautomated method (SAM) for total nitrogen in fertilizers has been developed which parallels the official first action semiautomated method for crude protein in feeds, 7.B05–7.B11. The SAM is simple, accurate, precise, flexible, rapid, and requires a minimum of laboratory space. Nitrate was reduced and organic nitrogen materials were digested by the sulfuric-salicylic acid chemistry in the block digestor. The nitrogen, as ammonia, in the digestate was determined automatically at the rate of 40 samples/hr with the automated ammonia analysis system. A small amount of CuSO4, (33 mg/sample) as the SAM digestion catalyst gave total recovery of organic nitrogen in fertilizer. Repeated analyses by the SAM and the AOAC official final action comprehensive nitrogen method (CNM) were made on Magruder fertilizer check samples, liquid and suspension fertilizers, and bulk blended commercial fertilizer materials. Average per cent nitrogen in liquid and suspension samples was higher by the SAM than by the CNM when sample weights similar to those for solid fertilizer were used. The precision of the SAM on liquids also agreed closely with that by the CNM. The only limitation of the semiautomated method was for fertilizer samples containing a Cl/NO3 ratio greater than 0.75 w/w. The SAM recoveries on 3 samples with very high Cl/NO3 ratios wert 94.1–99.1% of those by the CNM. Precision was also less than on any other samples. The average per cent nitrogen found for all experimental samples was 14.68 by the SAM and 14.67 by the CNM. The average relative standard deviation (RSD) for all 22 samples was 1.06% by the SAM and 0.74% by the CNM. When 3 samples with high Cl/NO3 ratios (&gt;0.75) were excluded, the average per cent nitrogen was 15.77 (CNM) and 15.81 (SAM); respective RSDs were 0.68 and 0.65% for the SAM and CNM, respectively. A comparison of results on 405 commercial fertilizer samples by both methods showed an average difference (SAM — CNM) of + 0.017% nitrogen and aver age relative difference of 1.23%.
Gas-Liquid Chromatographic Determination of Trans Unsaturation in Fats and Oils on Packed Columns: Preliminary Studies
Authors: Conacher Henry B S , Iyengar Jagannath R , Beare-Rogers Joyce L 
Published: February 2020

Abstract
Trans isomers in several methyl ester mixtures and in some commercial margarines were separated on a 15′ × ⅛″ stainless steel column containing 10% Silar 10C as stationary phase. With the methyl ester mixtures, good agreement was obtained among known trans contents, trans contents determined by infrared (IR) spectroscopy, and trans contents determined by gas-liquid chromatography (GLC). With commercial margarines, agreement between IR and GLC results was less satisfactory; the latter were approximately 80–85% of the former when trans contents were &gt;20%. When trans contents were &lt;20%, discrepancies were larger. This was considered due to overlap of certain cis and trans positional isomers.
Gas-Liquid Chromatographic Determination of the Plant Growth Regulator Ancymidol in Plant Tissue, Soil, and Water
Authors: West Sheldon D , Day Edgar W 
Published: February 2020

Abstract
A method is presented for the determination of the plant growth regulator ancymidol (α-cyclopropyl-α-(4-methoxyphenyl)-5-pyrimidinemethanol) in plant tissue, soil, and water. Residues are converted to an electron-capturing derivative with phosphorus tribromide prior to analysis by gas-liquid chromatography. The method is sensitive to about 0.10 ppm for plant tissue, 0.02—0.05 ppm for soil, and 0.02 ppm for water. Recoveries have averaged greater than 70% for all types of samples.
Assessment of Analytical Method Performance Characteristics : Systematic Error
Authors: Dols Thomas J , Armbrecht Bernard H 
Published: February 2020

Abstract
A random review of the analytical literature shows the need to define more clearly the terms for techniques that are used to assess the merits of analytical methods for a particular purpose. One such performance characteristic is the systematic error or bias of a method. This term is defined and contrasted with other terms commonly used in method assessment. Components of the systematic error are described and techniques are given for their measurement.
Spectrophotometric Determination of Capsaicin
Authors: Ramos Palacio José Jorge 
Published: February 2020

Abstract
A rapid method has been developed for determining the pungency of hot paprika. Paprika is extracted with ethyl acetate, and an ethyl acetate solution of vanadium oxytrichloride is added just before reading at 720 nm. The method is sensitive for small quantities, i.e., less than 0.05%, and it is not necessary to isolate and purify the capsaicin.
High Pressure Liquid Chromatographic Determination of Ethopabate in Feeds
Authors: Schronk Leonard R , Colvin Billy M , Hanks Alan R , Bushway Rodney J 
Published: February 2020

Abstract
A high pressure liquid chromatographic (HPLC) method is described for determining ethopabate in poultry feeds. Feed samples containing ethopabate are finely ground, extracted 30 min by sonification with methanol-water (80+20), and filtered. The extract is cleaned up on an alumina column, and the first 4 ml eluate collected is analyzed. The drug is eluted through a μBondapak C18 column with acetonitrile-water (30+70) at a flow rate of 1.4 ml/min and detected by ultraviolet absorption at 280 nm. Chromatography is complete in 7 min, and detector response is linear. The drug is quantitated by peak height ratios. The procedure described is reproducible and shows good agreement with the official AOAC colorimetric method. The lower limit of detection is 2 ng by HPLC, making the method applicable to residue analyses.
Atomic Absorption Spectrophotometric Determination of Dibutyltin Dilaurate in Finished Feeds: Collaborative Study
Authors: George Glenn M , Frahm Larry J , McDonnell J Patrick 
Published: February 2020

Abstract
Dibutyltin dilaurate is administered in the feed as an active drug for the removal of large roundworms, cecal worms, and several species of tapeworms from chickens and turkeys. The drug is extracted from finished feed with warm CHCl3, the CHCl3 extract is filtered, and a 25 ml aliquot is concentrated in the presence of methanol until all traces of CHCl3 are removed. The methanol solution is diluted and filtered to remove feed interferences, and then aspirated into an atomic absorption spectrophotometer with a triple-slot burner head, using an air/acetylene flame. The instrument response to tin at 286.3 nm is recorded. Recoveries of 100.5–101.9% tin were obtained for laboratory-prepared feeds. This method was collaboratively studied. The average recovery for dibutyltin dilaurate from 3 feed samples for 8 collaborators was 98.3% with an average coefficient of variation of 5.83%. The method has been adopted as official first action.
High Pressure Liquid Chromatographic Determination of Sulfanitran and Dinsed in Medicated Feeds and Premixes
Authors: Eaves Kathleen L , Colvin Billy M , Hanks Alan R , Bushway Rodney J 
Published: February 2020

Abstract
A simple reverse phase high pressure liquid chromatographic method is described for determining sulfanitran (acetyl-p-nitrophenylsulfanilamide) and Dinsed (dinitrodiphenylsulfonylethylenediamine) in a variety of feed premixes and formulations. Feed premixes are extracted with dimethylformamide, and formulated feeds are extracted with hot methanol. The extract is filtered through medium porosity paper and injected into a liquid chromatograph equipped with a 254 nm ultraviolet detector and a 30 cm column packed with μBondapak C18. The mobile phase is acetonitrile-water (45+55) at a flow rate of 1.0 ml/min. Chromatography was complete in 10 min and peak heights were used for quantitation. Comparison of analyses of commercial samples by this method and by the AOAC colorimetric method, 42.176–42.179, showed close agreement. Recovery of spiked feed samples ranged from 98 to 105%. Butynorate and roxarsone, 2 other drugs which are normally found in combination with sulfanitran and Dinsed, do not interfere.
High Pressure Liquid Chromatographic Determination of Uncombined Intermediates and Subsidiary Colors in Orange B
Authors: Singh Manjeet 
Published: February 2020

Abstract
A high pressure liquid chromatographic (HPLC) method has been developed for isolating and determining uncombined intermediates and subsidiary colors in Orange B. Samples of Orange B containing 0.1–0.3% naphthionic acid, 0.05–0.2 % phenylhydrazine-p-sulfonic acid, 0.2–0.8% pyrazolone-T and ethyl ester of pyrazolone-T, 0.2–1.0% 3-[(4-sulfo-l-naphthalenyl)-azo]-4-amino-l-naphthalenesulfonic acid, and 0.1–6.0% Orange K were prepared and analyzed by using this method. Recoveries ranged from 95 to 103%, except for the phenylhydrazine-p-sulfonic acid which ranged from 95 to 140%. Ten samples of Orange B were analyzed by conventional column and thin layer chromatographic methods as well as by the HPLC method. Good agreement was obtained for naphthionic acid, Orange K, and naphthionic acid plus the naphthionic acid subsidiary.
Analysis of Pesticide Residues by Chemical Derivatization. V. Multiresidue Analysis of Eight Phenoxyalkanoic Acid Herbicides in Natural Waters
Authors: Agemian Haig , Chau Alfred S Y 
Published: February 2020

Abstract
A multiresidue method is presented for the gas-liquid chromatographic determination of phenoxyalkanoic acid herbicides in natural waters. Extraction efficiencies of different organic solvents are considered in developing a solvent extraction scheme for these herbicides from water. Reactions for derivatizing these compounds by using pentafluorobenzyl bromide, boron trichloride-2-chloroethanol, and dicyclohexylcarbodiimide-2-chloroethanol were studied in order to obtain extracts with low blanks to provide the lowest detection limits. Advantages and disadvantages of the 3 methods are discussed. Retention times are twice as long for the pentafluorobenzyl (PFB) esters as for the 2-chloroethyl (2-Cl) esters under the same conditions, although electron capture sensitivity to the former was greater. The PFB esters are easier to form, but the 2-Cl reaction is more specific for these herbicides. Solutions from the boron trichloride reaction gave the cleanest blanks.
Detection of Residual Penicillins in Milk by Using a Bacillus stearothermophilus Disk Assay
Authors: Ouderkirk Larry A 
Published: February 2020

Abstract
A paper disk method based on a procedure described by the International Dairy Federation is presented for the detection of 4 β-lactam antibiotics (penicillin G, ampicillin, cephapirin, and cloxacillin) in whole milk. Bacillus stearothermophilus var. calidolactis, prepared as a stable spore suspension, was used as the test organism. Levels of 0.005 unit penicillin G/ml, 0.005 μg ampicillin or cephapirin/ml, and 0.05 μg cloxacillin/ml were readily detected in whole milk. Results were produced in 3–4 hr. The method offers several advantages, including greater simplicity, sensitivity, and rapidity, over methods now commonly used to detect residual levels of these drugs in milk.
Fluorometric Determination of Histamine in Tuna: Collaborative Study
Authors: Staruszkiewicz Walter F 
Published: February 2020

Abstract
Six samples of canned tuna, albacore, yellow-fin, and skipjack, in water or oil pack were analyzed in duplicate by a fluorometric method and the AOAC colorimetric method. For the fluorometric method, recoveries of histamine added to acceptable tuna averaged 99% with a range of 91 to 107%. Agreement between laboratories for the analyses of decomposed tuna containing 20–200 mg histamine/100 g sample was excellent. Results from the fluorometric method are comparable with those from the AOAC colorimetric method ; the fluorometric method has been adopted as official first action.
Nitration of Benzene as Method for Determining Nitrites and Nitrates in Meat and Meat Products
Authors: Wu Weh S , Saschenbrecker Peter W 
Published: February 2020

Abstract
Nitrites and nitrates in meat and meat products are determined by nitration of benzene in the presence of sulfuric acid. Nitrites are converted to nitrates by permanganate oxidation prior to nitration. The heat of dilution originating from the sulfuric acid is sufficient to complete the reaction. The final product, nitrobenzene, is determined by gas-liquid chromatography and electron capture detection. Peak height quantitation is both accurate and reproducible. Interferences from impurities are rarely encountered, and may be differentiated easily. The method also has potential application to samples other than meat.
High Pressure Liquid Chromatography of Folpet in Formulations: Collaborative Study
Authors: Carlstrom A Aner 
Published: February 2020

Abstract
A simple, rapid method is described for measuring folpet, specifying ultraviolet (UV) detection after high pressure liquid chromatographic separation in a 30 cm by 4 mm column packed with 10 μm diameter silica gel. Formulations are extracted with methylene chloride which contains dibutyl phthalate as an internal standard. After inert materials are precipitated, the supernate is added directly to the column, and the compound is quantitated by peak height ratios. Most pesticides commonly formulated with folpet do not interfere, nor do the related compounds captan and captafol. Retention times and UV response factors relative to folpet are listed for the pesticides most commonly formulated with folpet. Sixteen collaborators made single determinations on 6 samples. The average coefficients of variation were 0.95% for the 2 technical samples, 1.77% for the two 50% wettable powders, and 1.12% for the two 5% dusts. No systematic error was detected. The method has been adopted as official first action.
Determination of Vinylidene Chloride in Saran Films by Electron Capture Gas-Solid Chromatography and Confirmation by Mass Spectrometry
Authors: Birkel Thomas J , Roach John A G , Sphon James A 
Published: February 2020

Abstract
A method is presented for determining vinylidene chloride (VdC) in Saran food packaging films by using electron capture gas-solid chromatography. The VdC present was confirmed by combined gas-solid chromatography-mass spectrometry, employing selected ion recording. The method is capable of detecting ≥5 ppm VdC in films. Production lots of Saran film were analyzed and found to contain 6–30 ppm VdC.
Aflatoxin in Corn: Evaluation of Filter Fluorometer Reading of Minicolumns
Authors: Shotwell Odette L , Goulden Marion L , Kwolek William F 
Published: February 2020

Abstract
A minicolumn method using a filter fluorometer was compared with thin layer chromatography for determining aflatoxin in com. The minicolumn-fluorometer method identified many more samples as aflatoxin-positive than the AOAC CB method. Some corn samples contain a blue-fluorescing substance that interferes with minicolumn chromatography of aflatoxins. Aflatoxin levels measured by the minicolumn-fluorometer method did not correspond to those obtained by the CB method. The mention of firm names or trade products does not imply that they are endorsed or recommended by the U.S. Department of Agriculture over other firms or similar products not mentioned.