bluuebunny/crossref_metadata_2025_split huggingface dataset:
Analytical Constituents of Strawberry and Raspberry and Their Change in Jam Production
Authors: Ryan John J , Dupont Jo Anne 
Published: February 2020

Abstract
The constituents of strawberry and raspberry have been studied in order to regulate the fruit content of jams made from these fruits. Four constituents, potassium, insoluble solids, amino acids, and phosphorus, were examined to ascertain the variation, means, and minimum acceptable values. From data taken after about 1950 from these laboratories and from the literature, the variation of the first 3 constituents was less than 30% and acceptable, while that of phosphorus was too large and rejected. Strawberry and raspberry fruit samples of known constituent content were processed into jams and the amount of fruit in jam was estimated by using the constituent values. There was little or no difference between the per cent fruit in jams found by using potassium and insoluble solids and the true values determined by weighing. The percentage of fruit using total amino acid values was unreliable and could not be used. Minimum and mean values determined for strawberry jam containing 52% fruit are, for potassium, 45 and 77 mg/100 g and, for insoluble solids, 0.49 and 0.87 g/100 g.
Determination of Sulfaquinoxaline in Feeds: Collaborative Study
Authors: Szalkowski Chester R 
Published: February 2020

Abstract
In the method developed, sulfaquinoxaline is extracted from the feed sample with dimethylformamide and separated from interfering substances by chromatography on alumina. The isolated sulfaquinoxaline is diazotized and coupled in the presence of zirconium. The color complex is then extracted with butanol and measured at 550 nm. Recoveries of sulfaquinoxaline from feeds reported by 13 collaborators ranged from 96 to 101%, with a coefficient of variation of 5%. This assay method is suitable for determining sulfaquinoxaline at all levels and has been adopted as official first action, to replace methods 38.139 and 38.140–38.141.
Polychlorinated Terphenyls as Potential Contaminants of Animal Products
Authors: Fries George F , Marrow George S 
Published: February 2020

Abstract
The polychlorinated terphenyl (PCT) Aroclor 5460 has been used in a sealant for concrete stave silos. PCT residues were found in samples of wall scrapings, silage, and milk from farms known to have affected silos. The PCTs are complex mixtures, making identification and quantitation difficult. The samples were allowed to react with SbCl5 to form the 3 tetradecachloroterphenyl derivatives. Formation of the derivatives facilitated identification of PCT residues by gas-liquid chromatography. It also appears to be the most promising approach to a quantitative method.
Versatile Combustion-Amalgamation Technique for the Photometric Determination of Mercury in Fish and Environmental Samples
Authors: Willford Wayne A , Hesselberg Robert J , Bergman Harold L 
Published: February 2020

Abstract
Total mercury in a variety of substances is determined rapidly and precisely by direct sample combustion, collection of released mercury by amalgamation, and photometric measurement of mercury volatilized from the heated amalgam. Up to 0.2 g fish tissue is heated in a stream of O2 (1.2 L/min) for 3.5 min in 1 tube of a 2-tube induction furnace. The released mercury vapor and combustion products are carried by the stream of O2 through a series of traps (6% NaOH scrubber, water condenser, and Mg(ClO4)2 drying tube) and the mercury is collected in a 10 mm diameter column of 24 gauge gold wire (8 g) cut into 3 mm lengths. The resulting amalgam is heated in the second tube of the induction furnace and the volatilized mercury is measured with a mercury vapor meter equipped with a recorder-integrator. Total analysis time is approximately 8 min/sample. The detection limit is less than 0.002 μg and the system is easily converted for use with other biological materials, water, and sediments.
Determination of Fluoride in Household Products by Ion-Selective Electrode and Gran’s Plot
Authors: Schick Ann L 
Published: February 2020

Abstract
In the method presented, variants from mixed electrolyte systems and interferences from complexing cations are avoided. Concentration rather than ionic activity is determined by the simplified combination of several techniques. Millivolt readings are taken as standard NaF is added to products diluted in a buffer background ; the initial fluoride concentration is then extrapolated according to Gran’s theory from a volume-corrected, semi-antilogarithmic plot. The method was applied to 12 reagents of various fluoride salts and to 10 products, including concrete etchers, stain removers, metal fluxes, metal cleaners, and oven cleaners. It could also be applied to wood preservatives and insecticides which contain fluorides. Product concentrations of fluoride ranged from 0 to 30%. Results agreed favorably with those from distillation and thorium nitrate titration methods. The standard deviation was 0.52, relative standard deviation, 2%, and standard recoveries, 98–104%. Sample preparation is adequate only for products containing inorganic fluorides. Products containing organically bound fluoride must be ashed. Eight laboratories analyzed 3 reagents and 5 products by the proposed method with excellent results. The amount of fluoride present ranged from 0 to 30%, w/v. The standard error from collaborative results ranged from 0.046 to 0.930. The method has been adopted as official first action.
Analysis of Ochratoxins A and B and Their Esters in Barley, Using Partition and Thin Layer Chromatography. II. Collaborative Study
Authors: Nesheim Stanley 
Published: February 2020

Abstract
To test the method of Nesheim et al., 6 samples wert; analyzed in 13 laboratories. The samples encompassed a blank and 5 samples containing one or more ochratoxins in the range 50–200 μg/kg. Two samples were spiked with the 4 ochratoxin standards and 3 were spiked with barley naturally contaminated with ochratoxin A. The confirmation of identity of ochratoxins A and B by preparation of their ethyl ester derivatives was also tested. The average recovery of standard ochratoxin A was 112% at levels of 45 and 90 μg/kg, with a 27.1% coefficient of variation calculated from analysis of variance, one analyst, one replicate. Similar satisfactory results were obtained for the ethyl esters of A and B at a level of 120 μg/kg. The results were unsatisfactory for ochratoxin B and for the esters of A and B at the 60 μg/kg level. The chemical confirmation test was satisfactory for both ochratoxins A and B. The method, including chemical confirmation, has been adopted as official first action as quantitative for ochratoxin A and qualitative for the other toxins.
Application of High-Speed Liquid Chromatography to the Analysis of Aflatoxins
Authors: Seiber James N , Hsieh Dennis P H 
Published: February 2020

Abstract
Partial resolution of aflatoxins B1, B2, G1, G2, and P1 was achieved by high-speed liquid chromatography (HSLC) on a porous layer silica adsorbent, using chloroform-isooctane as the eluting solvent and a 254 nm UV monitor for detection. The resolution was somewhat less than, although comparable with, that obtained by thin layer chromatography, using Adsorbosil-1 adsorbent and fluorodensitometric detection. The HSLC response to B1 and G1 was linear in the 400–3000 ng range, allowing application of the technique to the quantitative analysis of B1 and G1 in crude extracts of Aspergillus parasiticus cultures. The coefficients of variation (precision) were 4.2% for B1 and 23.2% for G1 in a series of 4 replicate injections. The advantages and limitations of the technique for quantitative analysis and isolation are compared with those of more conventional chromatographic methods.
Determination of Diuron in Wheat
Authors: Parouchais Constantin 
Published: February 2020

Abstract
A simplified analytical procedure is described for the determination of diuron residues in a large number of wheat grain samples. The sample is subjected to Soxhlet extraction with acetone, the extract is dissolved in an acetone-aqueous phase (1+5) and then extracted with petroleum ether, and diuron is extracted into methylene chloride and carbon tetrachloride. Electron capture GLC is the determinative step, with ultraviolet spectrophotometry as an alternative technique.
Proposed Modification of the Manometric Method for the Determination of Carbon Dioxide in Wine
Authors: Caputi Arthur 
Published: February 2020

Abstract
In the course of a comparative study of various methods for the determination of CO2 in wine, an anomaly was encountered in the manometric method. Results obtained from several apple wines were consistently 15–30 mg/100 ml higher with the manometric method than with the other methods under study. The problem was traced to the formation of CO2 from components of these particular wines due to addition of the H2O2 used in the method to oxidize SO2, which was deemed to be a potential source of interference. Elimination of the H2O2 from the procedure avoided the problem. No measurable effect on results was found with the addition of up to 400 mg SO2/L, even in the absence of H2O2. Either deletion of the H2O2 from the procedure or subtraction of a degassed blank eliminated the problem. It is recommended that method 11.053–11.057 be revised by the addition of a blank to be prepared by degassing a duplicate wine sample at room temperature under about 27″ vacuum for 1–2 min and subjecting it to the same analysis.
Collaborative Study of the Flame Photometric Method for Sodium in Fertilizers
Authors: Corominas Luis F 
Published: February 2020

Abstract
Both methods for determination of sodium in fertilizers, 2.117 (10th edition) and 2.132–2.135 (11th edition), were studied, as well as the influence of resin treatment on the accuracy of results. Four samples containing 4–14% sodium were analyzed. The best accuracy was found for method 2.132–2.135 with the resin treatment omitted. The Sb values increased with greater sodium content; however, accuracy was not affected. The resin treatment in method 2.135 has been repealed, official first action, and an additional standard curve in the 0–10 ppm sodium range has been added for sodium concentrations lower than 1%.
Nitrogen in Feed and Fertilizer
Authors: Rexroad Paul R 
Published: February 2020

Abstract
Low values by Raney powder method 2.056 have been obtained on a few samples from one manufacturer. The values ranged from 0.2 to 5.0% nitrogen low. In relation to pollution, further work is reported in investigating digestion conditions and use of copper as a catalyst in Kjeldahl digestions. Data show that certain digestion conditions that are rugged for 0.5 g nicotinic acid lead to solidification on cooling after digestion. Further study is indicated. Deletion of paragraph (c) from 2.061 is recommended.
Collaborative Study of the Microanalytical Determination of Iodine by Oxygen Flask Combustion
Authors: Lalancette Roger A , Steyermark Al , Lukaszewski Donna M , Kostrzewski Patti L 
Published: February 2020

Abstract
Twenty-two collaborators participated in the study of a specific method using oxygen flask combustion followed by mercurimetric titration of the resulting iodide. With the exception of 2 collaborators, all obtained acceptable results on m-iodobenzoic acid. Statistical evaluation of the data from all collaborators gave: x̿ = 51.07%, x̿ – theory = –0.10%, s̄ = 0.28, and sm = 0.94. When the results of 2 collaborators are omitted, the corresponding values are: 51.07%, –0.10%, 0.15, and 0.19, respectively. Similar results were obtained on p-nitroiodobenzene. The results from all collaborators gave: x̿ = 50.82%, x̿ – theory = – 0.14%, s̄ = 0.19, and sm = 0.43. When the results of 3 collaborators are omitted, the values are: 50.87%, –0.09%, 0.14, and 0.23, respectively. The method has been adopted as official first action, as an alternative to the Carius method, for the determination of iodine in organic compounds.
Color-Specific Reagent for Identification and Semiquantitation of Pyrethrins and Piperonyl Butoxide by Thin Layer Chromatography
Authors: Olive Boyce M 
Published: February 2020

Abstract
A color-specific reagent, a mixture of phosphoric, tannic, and acetic acids and acetone, has been adapted for the thin layer chromatographic identification and quantitation of pyrethrins and piperonyl butoxide in pesticide formulations. Approximately 1 μg of either pyrethrin or piperonyl butoxide can be detected as pink and blue spots, respectively, in aerosol and solid formulations.
Critical Evaluation of the AOAC Method of Analysis for Nitrite in Meat
Authors: Nicholas Rosemary A , Fox Jay B 
Published: February 2020

Abstract
Results of studies on the effects of 5 alternative procedures of sample preparation are presented. The standard deviations for the methods were 0.00505, 0.00142, 0.00307, 0.00265, and 0.00243, with the AOAC method giving the highest values for nitrite. The effects of some variables on the determination of the nitrite content of meat by the official method were also studied. These variables include the addition of mercuric chloride, duration of heating, rate of color reaction, and reagent preparation. The nitrite concentration as measured by the AOAC method varied with the initial dilution of meat sample. A number of compounds were added to the Griess reagent and nitrite solution to see whether they would affect the reaction. Reductants were found to interfere consistently. Suggestions for simplifying and improving the official method are made. These include omitting mercuric chloride, recrystallizing 1-naphthylamine before using, and allowing only 25 min for the completion of the color reaction, using a higher concentration of Griess reagent.
Lower Sulfonated Subsidiary Colors in FD&C Blue No. 1
Authors: Bell Sandra 
Published: February 2020

Abstract
Two postulated lower sulfonated dyes were prepared and purified, and analytical data were obtained. Two subsidiary dyes were isolated from commercial samples of FD&C Blue No. 1 by column and thin layer chromatography. The visible and infrared spectra of these compounds were obtained and found to be identical to those for the prepared lower sulfonated dyes.
Collaborative Study of an Automated Optical Somatic Cell Counting Method for Raw Milk
Authors: Kelley Wesley N 
Published: February 2020

Abstract
A collaborative study was conducted to compare tbe automated optical somatic cell counting method (OSCC) with the direct microscopic somatic cell counting method (DMSCC) for raw milk. Samples were prefixed with formaldehyde and introduced into an Auto-Analyzer system. Dilution, clarification, and cell counting were performed automatically. Eight collaborators participated in the study, analyzing 48 samples in duplicate, using 2 different sampling rates. The results were compared with DMSCC counts reported by 3 different analysts. Statistical results show that the standard deviation for the DMSCC method was 0.1086 and for the OSCC method, at a sampling rate of 30/hr, 0.0911. From comparison of results it appears that the OSCC method is as accurate as, and more precise than, the DMSCC method. The faster sampling rate of the OSCC method (60/hr) has some effect on precision but little effect on accuracy. The method has been adopted as official first action.
Toxic Heavy Metals in Vegetables and Forage Grasses in Missouri’s Lead Belt
Authors: Hemphill Delbert D , Marienfeld Carl J , Reddy Ravula S , Heidlage Walter D , Pierce James O 
Published: February 2020

Abstract
Missouri supplies approximately 75% of the U.S. production of lead. Lead poisoning of horses in the vicinity of one smelter alarmed local residents about the possible hazards of consuming their fruits and vegetables. County Extension Directors selected cooperators in 7 counties in the lead mining and smelting area and 3 “control” counties in N.C. Missouri to grow lettuce, radishes, and greenbeans for toxic metal analysis. Seed and cultural instructions were furnished all cooperators. All samples were washed in distilled water. Atomic absorption analyses detected the following maximum levels of Pb in μg/g dry weight: lettuce leaf 1324, radish root 518, and greenbean pods 136. Cd levels in μg/g dry weight were as follows: lettuce leaf 34.5, radish root 13.7, and greenbean pods 8.5. Vegetables from control counties contained markedly lower levels of Pb and Cd. Only one smelter is located in the new mining area and considerable Pb ore (essentially powdered PbS) is transported by rail or truck to smelters in older mining areas of S.E. Missouri. Forage grasses (Festuca arundinacea and Tridens flavus) were collected along ore truck and control routes. Maximum levels of Pb (4350 μg/g dry weight, unwashed) and Cd (4.32 μg/g) were detected in samples along highway rights-of-way of ore truck routes. Considerably lower levels were detected along control routes.
Polychlorinated Biphenyls and Polychlorinated Terphenyls in Canadian Food Packaging Materials
Authors: Villeneuve David C , Reynolds Lincoln M , Thomas Gordon H , Phillips William E J 
Published: February 2020

Abstract
A survey has been carried out to determine the extent of PCB and PCT content of Canadian food packaging materials. Samples were obtained from 120 manufacturers in early 1972, representing 19 food categories. A total of 569 samples were submitted for PCB analysis and the total number of components analyzed was 911. Of these 81.7% contained less than 1.0 ppm PCB, 14.9% contained 1–10 ppm PCB, and 3.4% contained in excess of 10 ppm PCB. A total of 445 samples were submitted for PCT analysis and the total number of components analyzed was 731. Of these, 84.5% contained less than 1.0 ppm, 11.4% contained 1–10 ppm, and 4.1% contained in excess of 10 ppm PCT. A total of 77 foods were analyzed for PCB of which only 2 contained in excess of 1 ppm PCB. A total of 73 foods were analyzed for PCT and none of these contained in excess of 0.05 ppm PCT.
High Resolution Infrared Spectra of Fragrance and Flavor Compounds
Authors: Morris Walter W 
Published: February 2020

Abstract
High resolution infrared spectra in the region from 4000 to 300 cm−1 (2.5–33 μm) are presented for 99 fragrance and flavor compounds. These compounds were isolated from commercial and natural sources and were purified by preparative gas-liquid chromatography. Nuclear magnetic resonance analysis was utilized in many cases for verification of structure. The 4 strongest infrared bands in the 1100–300 cm−1 region are also tabulated.
Improvement of Dissolution in the SOLIDprep Sampler by Ultrasonics
Authors: Urbányi Tibor , Brunskill William T , Lin Maria 
Published: February 2020

Abstract
This paper describes a novel device which is capable of disintegrating and homogenizing tablets within a very short time and with a minimum of investment. The modification on the existing SOLIDprep Sampler I can be performed in-house. An increase of assay efficiency of at least 50% was observed when these modifications were made. The advantages as well as the disadvantages of the modification are discussed in detail.
Collaborative Study of an Automated Method for the Determination of Total and Direct Available P2O5 in Fertilizers
Authors: Johnson Frank J 
Published: February 2020

Abstract
In a collaborative study, an automated method for the determination of total and direct available P2O5 was compared with the official gravimetric quinolinium molybdophosphate method, 2.023–2.025. Nine laboratories participated in the analysis of the 12 sample solutions, and the results were evaluated by the technique of closely matched pairs. The t-test showed no difference in the means of the results of the 2 methods. The estimates of the random, systematic, and total errors of the automated method all differed significantly from those of the official method when evaluated by the F-test. Further study of the automated method for P2O5 in fertilizers is not recommended.
Collaborative Study of the Quantitative Determination and Chemical Confirmation of Sterigmatocystin in Grains
Authors: Stack Michael E , Rodricks Joseph V 
Published: February 2020

Abstract
A quantitative method of analysis for sterigmatocystin in grains was studied collaboratively by 17 participants. The results show that 7 analysts had difficulty with the corn and oat samples because of an oily residue in the sample extracts which interfered with sterigmatocystin on TLC plates. Barley and wheat samples were analyzed without difficulty. All of the quantitative results show the type of random error expected for visual analyses of TLC plates. Confirmative tests for sterigmatocystin were carried out without difficulty. The methods for the quantitative determination of sterigmatocystin in barley and wheat and the chemical confirmation of sterigmatocystin have been adopted as official first action.
Collaborative Study of Modified AOAC Moisture Method and Other Rapid Moisture Methods for Analysis of Meat and Meat Products
Authors: Pettinati Julio D , Metzger Virginia G , Van Horn David , Cohen Edward II 
Published: February 2020

Abstract
Three new methods for determining moisture content of ground beef, frankfurters, and fresh pork sausage were tested collaboratively by 10 laboratories. Results were compared with those obtained by AOAC official methods. The new methods involved: 1) use of a gravity oven at 125°C in place of a mechanical convection oven, 2) exposure of samples to IR radiation for 40 min, and 3) azeotropic distillation for 30 min, using either cumene, m-xylene, or 2-octanol. Determinations of moisture content by the use of a gravity oven and IR radiation were in agreement with the official methods, but azeotropic distillation with any of the 3 solvents gave lower values for all 3 types of meat product. The expected standard deviation, se, averaged for the 3 types of meat product in per cent moisture was as follows: gravity oven, ±0.65; IR radiation, ±1.18; and azeotropic distillation, ±0.79, ±0.86, and ±0.98, using cumene, m-xylene, and 2-octanol, respectively. For the official methods, ±0.64% moisture was obtained for se. An amendment to the official final action method for the determination of moisture in meat and meat products, 24.003(b), was adopted as official first action to provide for the optional use of an air oven.
Colorimetric Determination of Pyrimethamine in Feeds
Authors: Garber John B , Fink David W , Szalkowski Chester R 
Published: February 2020

Abstract
A method, based upon an acid dye ion-pair extraction colorimetric measurement with bromcresol green reagent, has been developed for the determination of pyrimethamine at the 5 ppm level in feeds. Pyrimethamine is extracted from the feed into benzene and separated from interferences by solvent partition and chromatography on alumina. Amprolium, ethopabate, and sulfaquinoxaline do not interfere with pyrimethamine determinations by this method.
Modified Delves Cup Atomic Absorption Determination of Lead in Blood
Authors: Barthel William F , Smrek Ann L , Angel Gloria P , Liddle John A , Landrigan Philip J , Gehlbach Stephen H , Chisolm J Julian 
Published: February 2020

Abstract
A modification of the Delves atomic absorption micro method for blood lead determinations is presented. The principal differences between the present modification and the original Delves method are the improvement in hardware to overcome problems in reproducibility and a char method to essentially eliminate the smoke peak which normally causes serious interference. The method has been applied to several different types of blood samples with excellent results.