bluuebunny/crossref_metadata_2025_split huggingface dataset:
Identification of Antibiotics in Pharmaceutical Preparations. I. Identification of Penicillin Types
Authors: Weiss Peter J , Taliaferro Brenda , Huckins Robert , Chastonay Richard 
Published: February 2020

Abstract
Methods for the rapid confirmatory identification of various penicillin types in pharmaceutical preparations are presented. Ultraviolet absorption spectra are useful after simple purification, and thin layer chromatography is applicable in some cases. A method based on differential distribution between chloroform and buffer phases, using solutions prepared for routine potency assays, can also be used
False-Positive Coagulase Reactions in the Characterization of Microorganisms Isolated from Foods
Authors: Litkenhous Claudia J , Baer Edward F , Gilden Mildred M , Bromer Marcia B 
Published: February 2020

Abstract
From 3578 cultures tested for coagulase production, 66 suspected false-positive coagulase cultures were selected on the basis of delayed clotting time (3—4 hr). Coagulase production by these cultures was compared, using citrated rabbit plasma and citrated rabbit plasma containing heparin. Twentynine of these cultures were also tested, using plasma containing EDTA. Results indicate that either EDTA or heparin should be used in conjunction with citrated plasma to eliminate false-positive reactions, or, if citrated plasma is used, that all delayed positives (3—4 hr) be considered suspect and additional confirmatory tests be performed
Extraction and Estimation of Polycyclic Aromatic
Hydrocarbons in Total Diet Composites
Authors: Howard John W , Fazio Thomas , White Richard H , Klimeck Barbara A 
Published: February 2020

Abstract
A general method for polycyclic aromatic hydrocarbons and a specific procedure for benzo(a)pyrene in various total diet composites (dairy products; oils, fats, and shortenings; beverages; meat, fish, and poultry; and root vegetables) have been developed. Recoveries ranged from 75 to 100% at the 2 ppb level. Pyrene and fluoranthene were found to be present in all of the total diet samples analyzed. Trace quantities of benzo ( a ) pyrene, benzo(k)- fluoranthene, benzo ( b ) fluoranthene, and other hydrocarbons were isolated from various lots of the oils, fats, and shortenings composites.
Comparison of Optical Emission and Atomic Absorption
Methods for the Analyses of Plant Tissues
Authors: Brech Frederick 
Published: February 2020

Abstract
Practical farmers are now realizing the value of plant tissue assays for trace metals and many laboratories offer services for such analyses by optical emission spectroscopy. The newer technique of atomic absorption could also be used, but not as many elements can be detected because the dynamic range of concentration for some elements is limited and the analyses take longer. A study of these limitations was made in order to improve the applicability of the atomic absorption method; Al, Si, and Mo can now be measured by this method.
A New Direct Colorimetric Method for Determining
Aldehydes in Alcoholic Beverages
Authors: Owades Joseph L , Dono Joseph M 
Published: February 2020

Abstract
A direct, colorimetric method for determining aliphatic aldehydes in alcoholic beverages has been developed. Free acetaldehyde and acetaldehyde bound to bisulfite and to alcohol (acetal) can be determined on separate aliquots. 3-Methyl-2-benzothiazolinone hydrazone hydrochloride reacts with the aldehydes to form a highly colored compound which is measured spectrophotometrically. The average recovery of acetaldehyde added to various wines and distilled liquors was about 98% ; levels of about 30—175 ppm were detected
Efficiency Parameters of Gas Chromatography Columns
Used in Pesticide Residue Analysis
Authors: Bostwick David C , Giuffrida Laura 
Published: February 2020

Abstract
The parameters in the preparation and operation of columns used in the gas chromatography of pesticide residues were studied and effects of varying each were compared. The parameters investigated were column length, diameter, configuration, amount of liquid phase, and solid support mesh size. Experimental conditions have been determined for more efficient columns, as follows: 4—10% liquid phase, 4 mm i.d column, length not less than 6 feet, 100—120 mesh for 6 foot column, 80—100 mesh for 6—12 foot columns
Effects of Chemical Preservatives and Storage on
Constituents Used to Characterize Lemon Juice
Authors: Vandercook Carl E , Guerrero Henry C 
Published: February 2020

Abstract
The effects of sulfur dioxide, sodium benzoate, and potassium sorbate preservatives on the analytical methods for chemically characterizing lemon juice were studied. None of the preservatives had any effects on the analyses for total acidity as citric acid, the l-malic acid, the UV absorbance at the 330 m/x peak (referred to as the total phenolics), or the formol determination of total amino acids (after expelling the S02 by boiling 1 min). The study was continued over storage periods of up to 17 weeks at room temperature and 6 weeks at 30 °C. The constituents measured remained relatively stable except for some small but statistically significant changes that were apparently a function of both the juice and, in the case of the total phenolics, the preservative used. For practical applications, the changes did not affect the multiple regression approach to the chemical characterization of lemon juice
Collaborative Study of "A Versatile Procedure for Assay of
Aflatoxins in Peanut Products," Including Preparatory Separation and Confirmation of Identity
Authors: Eppley R M , Stoloff L , Campbell A D 
Published: February 2020

Abstract
collaborative study of the CB procedure for aflatoxin in peanut products was carried out on naturally contaminated peanut butter and peanut meal and on peanut butter to which known amounts of aflatoxin Bx and Gi were added. Part of the study included preparatory isolation of the aflatoxin Bx fovind in the naturally contaminated samples and confirmation of the identity by both chemical and biological tests. The results from 13 collaborators demonstrate both between- and withinlaboratory precision and accuracy equal to the official, first action procedure; advantages in speed and convenience were noted. The preparatory separation was easily accomplished with clear chemical and biological proof of satisfactory isolation by seven of the nine participants in this phase of the study.
Analysis of Carbaryl in Formulations
Authors: Broderick E J , Sherman R M , Mack G L 
Published: February 2020

Abstract
Four methods of analysis for carbaryl in mixed formulations were compared. The ultraviolet absorption method is the most sensitive but the least specific becavise of many interferences. The alkaline distillation method is the least sensitive and is subject to interference from several common pesticides. The infrared and near infrared are intermediate in sensitivity and relatively free from interference. The near infrared was the method of choice on the basis of specificity, accuracy, sensitivity, and rapidity.
Separation of Penicillins by Paper and Thin Layer Chromatography
Authors: Hellberg Hans 
Published: February 2020

Abstract
The development of a paper and a thin layer chromatographic method for separating many of the most common penicillins is described. The separation on thin layer plates of the two epimers of phenoxyethyl penicillin (phenethicillin) and phenoxypropyl penicillin (propicillin) as their a-penicilloic esters is also reported.
Fat as a Factor in the Epimerization of Chlortetracycline in Feeds
Authors: Katz Stanley E , Fassbender Carol A 
Published: February 2020

Abstract
Fats were investigated in depth as a contributing factor in the conversion of chlortetracycline to epichlortetracycline in feeds. Fats with a free fatty acid content of 0.4— 100% and iodine values of 0.3—132 from both animal and vegetable sources were studied. An average of 12.5% of the added chlortetracycline potency was converted to epichlortetracycline but neither free fatty acid content nor unsaturation could be shown to be contributory factors to the epimerization reaction. Fats, per se, accelerated the rate of the attainment of equilibrium between chlortetracycline and epichlortetracycline but in themselves did not change the equilibrium point.
Collaborative Study of the Ultraviolet Spectrophotometric Determination of Sulfoxide in Formulations
Authors: Haus Joseph B , Manolev Lazar 
Published: February 2020

Abstract
A spectrophotometric method for the analysis of sulfoxide formulation was studied by six collaborators. The method consists of separating the sulfoxide from other components by column chromatography on silicic acid with three successive eluting solutions: chloroform, 2% acetone in chloroform, and 1 0% acetone in chloroform. Sulfoxide is removed in the last eluate and is determined by UV spectrophotometry. Solvents, emulsifiers, pyrethrins, compounds related to sulfoxide, and other insecticides are separated by the column. Results on standard samples of four formulations showed good agreement between samples and laboratories with the exception of one sample which, because of its complex nature and low sulfoxide content, resulted in poor correlation within and between the laboratories. It is recommended that the method for the assay of sulfoxide formulations be adopted as official, first action.
Determination of Trace Component Distribution in Illicit Spirits by Neutron Activation Analysis (NAA), Atomic Absorption (AA), and Gas-Liquid Chromatography (GLC)
Authors: Hoffman C M , Brunelle R L , Pro M J , Martin G E 
Published: February 2020

Abstract
Trace inorganic constituents of illicit spirits were measured by neutron activation analysis and atomic absorption; organic constituents were determined by gas-liquid chromatography. These identifying components were evaluated statistically, and the data were applied to actual case work. Results also show that the use of multiple techniques increased the probability of matching two or more samples in determinating a common source.
Gas Chromatographic Separation and Quantitative Estimation of Barbiturate Mixtures in Solid Dosage Forms
Authors: Allen John L 
Published: February 2020

Abstract
A gas chromatographic method has been described for the analysis of mixed barbiturates in solid dosage forms. Analysis on a 10% SE-30 column gave good separations for butabarbital, amobarbital, secobarbital, pentobarbital, and/or phenobarbital; amobarbital is not separated adequately from pentobarbital. An internal standard, mephobarbital, is used to minimize injection errors. The method gives both good quantitative and qualitative results on the barbiturates investigated. Two synthetic tablet mixtures were analyzed by this procedure and recoveries were 98—103%. It is recommended that the method be subjected to collaborative study.
Collaborative Study of the Separation and Spectrophotometric Determination of Acetylcarbronial and Bromisovalum
Authors: Look James M 
Published: February 2020

Abstract
The method for Celite column separation and infrared spectrophotometric determination of acetylcarbronial and bromisovalum, reported to the AOAC last year, was studied collaboratively. Nine collaborators made duplicate determinations for each ingredient on a powder from a commercial tablet and a powder prepared by the Associate Referee. Recovery on the authentic powder was 104.7 ± 3.1% for acetylcarbronial and 95.8 ± 2.5% for bromisovalum. The tablet powder assayed 101.1 ± 3 . 1 % of declared acetylcarbronial and 91 ± 3.6% of declared bromisovalum. The Associate Referee recommends that the method be adopted as official, first action
Comparison of Sample Preparation Methods for Phosphorus in Grains and Stock Feeds
Authors: Rash Aaron E 
Published: February 2020

Abstract
The nitric-perchloric acid digestion, 22.070(b) and 22.073, for the determination of phosphorus in grains and stock feeds was compared with three other methods of sample preparation (destruction of organic material) : quinoline molybdate precipitation, perchloric-sulfuric-sodium molybdate digestion, and the plant method. The values obtained by the nitric-perchloric acid method were not in good agreement with those obtained by the other methods studied. Six samples of commercial feeds and one barley sample were analyzed. The barley sample gave very poor recoveries by method 22.073.
Separation of Vitamins D2 and D3 as Isotachysterols D2 and D3 by Gas-Liquid Chromatography
Authors: Sheppard A J , Lacroix Denis E , Prosser A R 
Published: February 2020

Abstract
A method for the quantitative determination of 0.5—20 μg vitamins D2 and D3 by gas-liquid chromatography is described. Vitamins D2 and D3 are completely isomerized to their respective isotachysterol isomers by acetyl chloride as demonstrated by ultraviolet and infrared absorption data. Dihydrotachysterol D2, isotachysterol D2, and isotachysterol D3 are completely resolved with a 3% JXR on 100-120 mesh Gas Chrom Q column packing. Calibration studies show that each compound exhibited a characteristic dose-response plot. Therefore, one isomer cannot be used as a direct internal standard for the quantitative measurement of the other isomer.
Total Nitrogen in Fertilizers
Authors: Rexroad Paul R , Krause Gary F 
Published: February 2020

Abstract
A three-laboratory collaborative study was made of the comprehensive nitrogen method and the new Raney catalyst powder method for total nitrogen in fertilizers. Both methods worked quite well and, with minor modifications, they should provide the basis for a broader collaborative stvidy to provide an official method for total nitrogen in fertilizer applicable to all samples. The limitations of method 2.045 are reviewed and a rephrasing of the official applications of the method is recommended. Further work is recommended toward adoption of a new method and possible deletions or change of status in current official methods.
Sampling Bulk Fertilizers
Authors: Gehrke C W , Baker W L , Krause G F , Russell C H 
Published: February 2020

Abstract
An experimental "D" sampler, which encompasses a core of fertilizer in place, and a powered auger sampler are compared with official compartmented probe and stream samplers on dry mixed fertilizer from three types of blending plants in six states. Standard deviations reflecting variability and precision of the "D" tube indicate performance comparable or superior to the official samplers in both chemical and mechanical analysis. The powered auger compared favorably to the official samplers in chemical analysis, but comparison as to mechanical analysis could not be made because particle size reduction occurred. The official stream sampler failed to secure representative samples from baffle-type mixers when the discharge time was unusually short. Improved indexes of sampling accviracy and precision were secured for all samplers used. It is recommended that sec. 2.001(b), as expanded, be raised to official, final action status.
Extraction Procedures for DDT Residues in Firm Fruits and in Hay: Colorimetric Method
Authors: Wilderman Milton , Shuman Harry 
Published: February 2020

Abstract
The stripping (tumbling) procedure for residue removal is no longer considered adequate for DDT in firm fruits and hay. On the premise that barriers to extraction in fruit tissue do not exceed those in leafy vegetables, the isopropanol:hexane (1 + 2) blending extracting procedure was applied to chopped apple and peach samples with DDT added prior to extraction. Recoveries of 92-97% agreed with previous results by several investigators on vegetable products. Three procedures were compared for effectiveness in the removal of fieldincurred DDT residues from hay: the twostage blending-Soxhlet "exhaustive" procedure of Mumma et al., the 35% water: acetonitrile procedure of Bertuzzi et al., and isopropanol:hexane (1 + 2) extraction following sample hydration. All three procedures gave essentially equal results and the 35% water:acetonitrile procedure is recommended for adoption as official, first action.
Temperature-Dose Relationships with Aflatoxin on the Brine Shrimp, Artemia salina
Authors: Brown R F , Wildman J D , Eppley R M 
Published: February 2020

Abstract
Temperature-dose relationships with aflatoxin B1 were studied, using the brine shrimp, Artemia salina. Increase in temperature resulted in increased sensitivity by the brine shrimp to aflatoxin. Optimum sensitivity occurred at 37.5°C. Positive results were obtained at 0.5 μg aflatoxin B1/ml artificial sea water with a mortality of over 60%. Greater than 90% mortality occurred at dose levels of 1.0 μ/ml and above. The test can be conducted in 24 hours, and highly trained personnel are unnecessary.
Determination of Sulfonamides in Milk
Authors: Houston Stanley F , Umstead John E 
Published: February 2020

Abstract
Sulfonamide residues were determined in milk by first treating the milk with acetone and acetic acid and then purifying and concentrating the sulfonamides on an ion exchange column. This method yields a low control reading, an achievement which has been difficult to obtain by other procedures. This control reading, which shows up as false sulfonamides, can result in erroneous recovery and residue data unless a correction procedure is used. The average recovery is 85%, the sensitivity is 0.1 ppm, and the control milk samples read less than 0.1 ppm
Microcrystalline Identification of Phenothiazine-Type Tranquilizers. I. Development of the Method
Authors: Andres Carolyn X 
Published: February 2020

Abstract
Microcrystalline reactions are described for the identification of twelve related phenothiazine-type compounds with six reagents (1% ammonium reineckate, 5% ammonium thiocyanate, gold chloride, picric acid, platinum bromide, and stannous chloride). The procedure involves the diffusion of a drop of reagent into a drop of a solution of substituted phenothiazine in HC1 ( 1 : 9 9 ) . The resultant crystalline derivatives are described, and photomicrographs are included as an additional identification guide. By the use of these microchemical tests, it is possible to detect and identify microgram quantities of promazine, chlorpromazine, trifiupromazine, mepazine, prochlorperazine, trifluoperazine, methoxypromazine, promethazine, propiomazine, fluphenazine, acetophenazine, and chlorprothixene. The method was successfully applied to ten trade-name drug products. A collaborative study is underway
The Effect of the Route of Administration of Single Doses of
p,Ṕ-DDT on Residues in Adipose and Liver Tissues
Authors: Mccully K A , Mckinley W P , Phillips W E J 
Published: February 2020

Abstract
p,Ṕ-DDT was administered orally, intraperitoneally, and intramuscularly (10 mg/kg body weight) to rats, sheep, chickens, rabbits, and guinea pigs. Animals were killed 5 days after dosing and fat and liver samples removed. All animals except chickens stored a greater concentration of total residues in the fat and livers following intraperitoneal injection than by oral or intramuscular administration. Residues in the fat demonstrated that oral administration of p,Ṕ-DDT resulted in greater conversion of p,Ṕ-DDT to p,Ṕ-DDD than administration by the other routes. Conversion appeared to be greatest in sheep (ruminant) and rabbits (functional cecum). Livers of all treated animals contained p,Ṕ-DDD residues, regardless of the route of administration
Determination of Fluorine in Feeds by the Fluoride Ion Activity Electrode
Authors: Torma Laszlo , Ginther Burton E 
Published: February 2020

Abstract
A specific ion electrode was utilized in the determination of fluorine in feed materials. A National Bureau of Standards rock phosphate standard sample, an AAFCO check feed sample, and commercial feed samples were analyzed by the specific ion electrode method. The results obtained by the developed method were compared with the results of the AOAC fluorine method (24.029—24.035). Comparison shows that the two methods are in very good agreement, but the specific ion electrode method is faster.
Solid State Fluorescence Emission of Aflatoxins on Silica Gel
Authors: Robertson James A , Pons Walter A 
Published: February 2020

Abstract
The solid state fluorescence emission maxima of aflatoxins B1, B2, G1, and G2 on silica gel range from 427 to 455 mµ, with excitation maxima at 368—369 mµ. Both the order and the magnitude of the relative fluorescence intensities of individual aflatoxins are different in solution and in the solid state on silica gel.
Identification and Quantitative Estimation of Aldrin Residues in the Presence of Interfering Materials in Samples of Plant and Animal Origin
Authors: Osadchuck M , Wanless E B 
Published: February 2020

Abstract
Aldrin is converted to dieldrin by epoxidation with m-ehloroperbenzoic acid and, after the removal of epoxidizing agent, the resulting derivative (dieldrin) is measured by GLC. The original amount of aldrin may be calculated from a predetermined per cent yield of dieldrin. Other substances with GLC responses similar to aldrin do not yield derivatives with GLC peaks in the region of dieldrin.
Gas Chromatography of Fusel Oils in Alcoholic Distillates
Authors: Kahn J H , Trent F M , Shipley P A , Vordenberg R A 
Published: February 2020

Abstract
A single gas-liquid chromatographic column is described which will separate all the major fusel oil components rapidly and directly without prior concentration or extraction procedures. Quantitative data obtained using a 1:1 2% 1,2,6-hexanetrio 1:2% glycerol column compare favorably with those of the official AOAC colorimetric fusel oil method. Four additional components may be determined simultaneously and quantitatively.
Collaborative Study of the Kjeldahl Method for Determination of Protein Content of Milk
Authors: Strang D R , Sherbon J W 
Published: February 2020

Abstract
Nitrogen in 12 milk samples was measured in 19 laboratories by the Kjeldahl method. Three of the 19 laboratories were excluded from statistical analysis because the nitrogen values they reported differed markedly from those reported by the remaining 16 laboratories. The average standard deviation for the determinations was 0.012% nitrogen, which is equal to 0.077% protein. Analysis of variance indicated that the error due to the laboratories effect was significant when 16 laboratories were considered. When the laboratories were sorted according to various experience criteria, the variations due to laboratories were significant. When the laboratories were blocked according to catalyst used, the variation among laboratories was not significant.
Thermistor Cryoscopic Determination of the Freezing Point Value of Milk Produced in North America
Authors: Henningson R W 
Published: February 2020

Abstract
A survey of the freezing point value of 660 milk samples, known to contain no added water, taken from dairying areas in 22 States and 4 Canadian Provinces was conducted during late spring of 1968. The data collected were subjected to analysis of variance and simple linear regression statistical procedures and tested for significant relationships and differences at the 5 and 1% levels. The mean freezing point value for all samples was estimated as —0.5404°C with a standard error of 0.0003°C and a standard deviation of —0.00676°C. Thirty-five (5.3%) of 660 samples yielded freezing point values of —0.530°C or higher; twenty-five (3.8%) yielded a freezing point value of —0.551°C or lower. Significant differences were found among mean freezing point values for States and for breeds.
Method for Extraction of Light Filth from Flours by Defatting and a Mineral Oil Flotation
Authors: Thrasher Joel J 
Published: February 2020

Abstract
AOAC methods 36.027 and 36.028 are only suitable for flours of low bran content. With these methods, fdter papers usually contain excessive amounts of plant debris and recoveries are low and varied. A new method has been developed that results in reproducible recoveries and cleaner filter papers. This method is applicable to flours with a wider range and a higher level of bran content.