bluuebunny/crossref_metadata_2025_split huggingface dataset:
Identification of Phenothiazine Derivatives and Analogs by X-Ray Diffraction. II. Active Substances in Pharmaceutical Formulations
Authors: De Leenheer A , Heyndrickx A 
Published: February 2020

Abstract
Procedures have been developed for the isolation of phenothiazines and chemically related compounds from pharmaceutical formulations, namely, injections, solutions, tablets, coated tablets, creams, sirups, lotions, and suppositories. In general, active substances are crystallized as picrates. A few compounds, however, gave better crystalline derivatives as free bases (levomepromazine and propericiazine), quaternary ammonium salt (thiazinamium), or chlorhydrate salts (amitriptyline and nortriptyline). The crystalline derivatives prepared were specifically identified by comparison of their Debye-Scherrer X-ray diffraction patterns with those for reference compounds obtained under the same conditions.
Atomic Absorption Spectroscopy for Determination of ppm Quantities of Copper and Nickel in Tea
Authors: Burke Keith E , Albright C H 
Published: February 2020

Abstract
An atomic absorption spectroscopic method is described for the quantitative determination of 0.0005–0.01% (5–100 ppm) copper and nickel in tea. After acid decomposition of the organic material, the sample is aspirated into an air-acetylene flame. Radiation at 324.7 nm from a copper hollow cathode is passed through the flame, and the attenuation is measured. The measurement is also made with radiation at 232.0 nm with a nickel hollow cathode. The spectrophotometer is calibrated with known concentrations of copper and nickel in the presence of a matrix similar to that of the samples. The method is applicable to all teas regardless of their geographical origin. Results from 7 collaborators on 6 samples are given. For one sample from 7 collaborators the following mean standard deviations were obtained for 32 determinations: copper 19.5±1.7 ppm and nickel 26.0±1.0 ppm. The method has been adopted as official first action.
Collaborative Study of Infrared Analysis of Dicamba–2-Methyl-4-Chlorophenoxyacetic Acid and Dicamba–2,4-Dichlorophenoxyacetic Acid Formulations
Authors: Malina Marshall 
Published: February 2020

Abstract
A collaborative study was conducted on direct and indirect infrared methods of analysis for both dicamba-MCPA aqueous formulations and dicamba-2,4-D aqueous formulations. Twelve laboratories participated in this study, including 3 international CIPAC member laboratories. The indirect methods require acidification, followed by extraction of the formulation samples before quantitative measurement, which is performed by comparing the absorbance of the sample to that of a prepared reference standard. In the direct methods, the absorbances of solutions of the untreated sample are directly compared with those of the prepared reference standard. The results on both formulations from the 12 collaborating laboratories exhibit excellent precision and accuracy for the indirect infrared method, with the following coefficients of variation: dicamba-MCPA, 0.059 and 0.063, respectively; and dicamba-2,4-D, 0.057 and 0.091, respectively. The method has been adopted as official first action. Five laboratories participated in the study of the direct infrared methods and, although results indicate that these methods also exhibit excellent precision, the accuracy obtained is less than desirable.
Semiautomated Determination of Nitrogen and Phosphorus in Feedstuffs
Authors: Law A R , Nicolson N J , Norton R L 
Published: February 2020

Abstract
A method is described which enables nitrogen and phosphorus in a wide range of feedstuffs to be determined from a single digestion. The method employs a conventional digestion on a semimicro scale followed by automated colorimetric analysis of the resulting ammonia and orthophosphate by the indophenol blue and molybdenum blue methods, respectively. Nitrogen is determined in the range from 0 to 15% and phosphorus in the range from 0 to 4%; the rate of analysis is 40 and 30 samples/hr, respectively, after digestion and dilution. The results obtained do not differ significantly from those obtained by proven manual methods, while considerable time, space, and reagents are saved.
Determination of Trace Amounts of Mercury in Fish Tissues: Results of a North American Check Sample Study
Authors: Uthe J F , Armstrong F A J , Tam K C 
Published: February 2020

Abstract
Three homogenized fish samples were distributed to 29 laboratories for analysis for mercury content. The majority (19) of the laboratories used acid digestion followed by atomic absorption analysis to measure the mercury content. Six laboratories used neutron activation; while 2 used dithizone methods and 2 used pyrolysis followed by flameless atomic absorption. Results from 4 laboratories were grossly aberrant or incomplete. Graphic analysis of the results on 2 samples showed that most laboratories tended to get either high or low results with both samples and that several had more consistent results with low fat samples than with high fat samples. Comparison of the combined results by flameless atomic absorption spectroscopy with those obtained by the flame method (t-test) showed that the latter gave just significantly lower results but much poorer precision. Differences between the combined results by flameless atomic absorption spectroscopy and those by neutron activation were probably insignificant.
The Ethical Obligations of the Forensic Scientist in the Criminal Justice System
Authors: Starrs James E 
Published: February 2020

Abstract
There is a definite need for standardization in the obligations of an ethical and moral character imposed upon the forensic scientist both prior to and during the trial. The responsibilities of the forensic scientist as a quasiimpartial witness or as a witness for either of the contending sides are analyzed with particular references to actual cases, some of which have drawn the attention of the courts in lengthy judicial opinions. Certain rough standards are proposed with particular instances in mind. In addition, more generalized criteria are suggested which should bind the activities of the forensic scientist in the criminal justice system. The matter of tactics and strategy is evaluated in connection with the description of ethical and moral norms to guide the forensic scientist, Use of the Microscope in Criminalistics
Use of Neutron Activation Analysis for the Characterization of Paper
Authors: Brunelle R L , Washington W D , Hoffman C M , Pro M J 
Published: February 2020

Abstract
A controlled study was carried out on 600 samples of various types of white and colored paper obtained from 10 different paper manufacturers with known production histories and dates. Neutron activation analysis was employed to measure the characterizing trace elemental compositions. Results indicated that (1) the papers examined were uniform with respect to their trace elemental compositions, (2) papers produced by different manufacturers are readily distinguishable qualitatively and/or quantitatively, (3) different batches of paper produced by the same manufacturer are generally qualitatively similar if produced within a short span of time (however, these specimens can be distinguished by quantitative analysis of the trace elements), and (4) different batches of paper produced by the same manufacturer at least 1 year apart are readily distinguishable qualitatively and/or quantitatively.
Protein Interference in Thiabendazole Determination
Authors: Jeffus Marshall T , Kenner Charles T 
Published: February 2020

Abstract
Protein in sufficient quantities interferes in the reductive step in determination of thiabendazole by AOAC Method II (38.154–38.157) but not by Method I (38.149–38.153). Limited results indicate that modification of Method I to allow measurement in the ultraviolet provides a simplified method of analysis for some feeds.
Effect of Reduced Drying and Extraction Time in Determining Meat Fat Content
Authors: Cohen Edward H , Swift Clifton E 
Published: February 2020

Abstract
The AOAC method for determining the fat content of meat was modified so that it can be applied more rapidly by processors in controlling meat product composition. A saving of 4.25 hr in drying and extraction time was effected without any significant loss in accuracy. Collaborative studies are suggested to reduce the time requirements for the official fat analysis of meat.
Gas-Liquid Chromatographic Determination of Cyclamic Acid
Authors: Conacher H B S , O’Brien R C 
Published: February 2020

Abstract
A quantitative GLC technique is presented for the determination of cyclamic acid in soft drinks. The procedure involves GLC analysis of the cyclamic acid after reaction with diazomethane, using methyl stearate as internal standard. Recoveries of known amounts of cyclamic acid added to water and to soft drinks ranged from 90 to 98%. The procedure permits simultaneous determination of cyclamic acid and saccharin.
Gas Chromatography of the Trimethylsilyl Derivatives of Flavanones
Authors: Coffin D E , Dupont J E 
Published: February 2020

Abstract
A procedure was developed for the detection and measurement by gas-liquid chromatography of the 4 flavanones isosakuranetin, naringenin, hesperetin, and eriodictyol as their trimethylsilyl derivatives. The derivatives were prepared by treatment of the flavanones with N,0-bis(trimethylsilyl) acetamide in N,N-dimethylformamide at room temperature. The derivatives of naringenin and hesperetin were separated, detected, and measured by gas-liquid chromatography on a column of OV-101 on Diatoport S with hydrogen flame detection. Isosakuranetin and eriodictyol derivatives could be detected but were not adequately separated by this system. These procedures were applied to the detection of the flavanones derived from orange and grapefruit juices.
Determination of Water in Molasses by Karl Fischer Method
Authors: Kviesitis Boris 
Published: February 2020

Abstract
Successful use of the method depends on several factors, one of which is the size of the sample because it affects the result of the titration. In this study, 2 sizes of cane molasses samples were tested and the results were compared with those from the vacuum oven method. The use of larger samples with or without the addition of surfactant increased the precision of the analysis. It is recommended that the Karl Fischer method for water determination in molasses and sugar sirups be subjected to collaborative study.
Automated Analysis of Sulfamethazine and Procaine Penicillin in Feed Premixes
Authors: Zagar John B , Ascione Peter P , Chrekian George P 
Published: February 2020

Abstract
An automated technique was developed for simultaneously evaluating mixtures of sulfamethazine and procaine penicillin in feed premixes each at levels of 20 g/lb. The system involves the separation of these drugs by an alkaline-chloroform extraction followed by the Bratton-Marshall color determination performed on each resulting phase. Quantitation progresses at a rate of 20 samples or 40 assays/ hr and is accomplished by direct comparison of samples to appropriate standards treated in a like manner.
Variations of Florisil Activity: Method to Increase Retentive Properties and Improve Recovery and Elution Patterns of Insecticides
Authors: Hall Edward T 
Published: February 2020

Abstract
The adsorptive capacity of 10 different lots of commercial Florisil (60-100 mesh) was tested by determining the recovery and elution patterns of 10 chlorinated and 6 organophosphate insecticides. Four lots were regular grade Florisil (calcined at 1200°F) and 6 lots were PR grade Florisil (calcined at 1250°F). All lots were tested as received and tested after washing with hot distilled water and re-igniting at 1250°F for 2.5 hr. Results indicated a wide variation in the activity and retentive properties of the untreated lots. Certain pesticides were not totally removed from the column by the respective eluant and some were irreversibly held on the column and not apparent in other eluants. After the washing and reigniting treatment, all lots of the PR Florisil gave satisfactory recovery and separation in the proper eluants. The lauric acid value was used to determine the quantity of Florisil to be placed on the column.
Herbicidal Carbamates: Extraction, Cleanup, and Gas Chromatographic Determination by Thermionic, Electron Capture, and Flame Photometric Detectors
Authors: Onley John H , Yip George 
Published: February 2020

Abstract
Extraction, cleanup, and gas chromatographic procedures have been developed for the determination of carbamate herbicides in food crops. Each sample is extracted with ethanol or an ethanol-water mixture and then cleaned up on a MgO-cellulose column. Determinations are made by gas chromatography, using thermionic and electron capture detectors; a flame photometric detector may also be used to quantitate and confirm those carbamates containing sulfur. Recoveries from apples, potatoes, alfalfa, corn, and soybeans at fortification levels of 0.01 to 10 ppm exceeded 80%.
Stability of Metallic Ethylene Bisdithiocarbamates in Chopped Kale
Authors: Howard Samuel F , Yip George 
Published: February 2020

Abstract
Chopped kale samples were fortified with maneb, zineb, or Dithane M-22, a maneb formulation. Samples were stored in a freezer or refrigerator and analyzed daily for 3 days. Using the carbon disulfide evolution procedure, the dithiocarbamate content in the samples was determined. Zineb was more stable than maneb or Dithane M-22 in both the frozen and refrigerated state. Immediately upon mixing, there was a loss of about 10% Dithane M-22 and 25% maneb. Freezing the samples prevented further losses.
Residues of Maneb and Ethylene Thiourea on Field-Sprayed Lettuce and Kale
Authors: Yip George , Onley John H , Howard Samuel F 
Published: February 2020

Abstract
Two crops, lettuce and kale, were treated with a maneb formulation at a rate of 2.4 lb active/acre. Samples were harvested at various times after application for residue analysis. The residues determined were maneb and ethylene thiourea (ETU). On lettuce, residues of maneb decreased from 45 to 5 ppm in 15 days. On kale, the decrease was from 90 to 15 ppm in 7 days. With both crops, ETU which was already present in the formulation did not accumulate, but quickly decreased from 0.6 ppm to undetectable amounts after 7 days.
Fading of Aflatoxin Spots on TLC Plates During Fluorescence Densitometry
Authors: Nesheim Stanley 
Published: February 2020

Abstract
Fading of fluorescence of aflatoxin spots on TLC plates has been previously associated with causes such as exposure of plates to UV light, air, heat, and humidity. In this study it was shown that the lamp-cooling effluent from the high intensity xenon lamp light source of a spectrofluorometer TLC plate scanner reduced the fluorescence of aflatoxins B1 and G1 by about 90%; whereas the B2 and G2 fluorescence was reduced by less than 25%. The fading can be prevented by covering the plate with another glass plate.
Micro determination of Nitrogen in Plant Tissues
Authors: Mitchell H L 
Published: February 2020

Abstract
In the semimicro method for nitrogen, the plant sample is digested with C11SO4 or HgO as catalyst in an acid medium, EDTA is added to prevent interference from metals, and the res ulting solution is neutralized to pH 7. Sod ium nitroprusside is added and the color is allowed to develop 1hr ; the absorbance is measured at 625 n m . The proposed method, with either CUSO4 or HgO, is applicable to dry or fresh plant tissues and yields results which are comparable to those obtained with AOAC 2.049-2.051.
Chlortetracycline Residues in Broiler Tissue and Organs
Authors: Katz Stanley E , Fassbender Carol A , Dorfman Donald , Dowling John J 
Published: February 2020

Abstract
Chlortetracycline was fed continuously to chicks at levels of 50–200 g/ton from the age of 1 day to 12 weeks; t h e tissue, blood, and organs were examined for residues. Average muscle tissue concentrations ranged from 0.036 to 0.109 μ/g in the feeding range, blood levels ranged from 0.043 to 0.076 μ/g, liver residues ranged from 0.058 to 0.199 μ/g? a n d kidney residues ranged from 0.377 to 1.147 μ/g- Tissue, blood, and liver residues disappeared 1 day after withdrawal from the medicated feed but measurable levels remained in the kidneys for 3 days. Storage studies of muscle tissues, intestinal analysis, and kidney levels all indicate a reservoir of activity, most probably the epimer form, in the tissue. Cooking, however, converted residues in the tissue to isochlortetracycline which has no known biological activity. Livers, however, retained some 31% activity after preparation.
Infrared Studies of DDT, Structurally Related Halogenated Pesticides, and Some Metabolites
Authors: Chen Jo-Yun T , Dority Roland W 
Published: February 2020

Abstract
Reference IR spectra of 29 purified halogenated pesticides are presented. The spectra were recorded with micro quantities of the purified pesticide compounds to facilitate identification of pesticide residue isolates. The compounds included DDT and related structures. The observed characteristic frequencies are tabulated in correlation tables, and their significance is interpreted in terms of the substituents and of the electromesomeric and mass effects of the substituents. The relevance of these effects to the stability and persistence of this class of pesticides is noted.
Collaborative Study of a Method for the Extraction of Light Filth from Canned Fish
Authors: Dent Russell G 
Published: February 2020

Abstract
Collaborative results are presented for a method proposed for light filth extraction from canned fish packed in water, oil, or vegetable sauces. The method utilizes an acid digestion and a hot mineral oil extraction from an aqueous phase in a Corning percolator. Recoveries are reproducible and filter papers are relatively clean. This method is recommended for adoption as official first action to replace procedure 40.064.
Mass Spectrometry of Volatile Derivatives. V. N-Dialkylnitrosamines
Authors: Saxby M J 
Published: February 2020

Abstract
Twenty-four dialkyl-N-nitrosamines have been studied under electron impact. They exhibit molecular ions which fragment by cleavage at the carbon atom of the longer alkyl chain and the resulting ion then expels the neutral fragment HNO. The molecular ions from many nitrosamines also lose a hydroxyl radical but deuteration experiments have failed to substantiate a general mechanism for this process. Loss of nitric oxide from the molecular ion was not found in any of the derivatives, except methyl ter 1.-butyl nitrosamine.
Screening Method for the Detection of Chlorodibenzo-p-dioxins in the Presence of Chlorobiphenyls, Chloronaphthalenes, and Chlorodibenzofurans
Authors: Williams D T , Blanchfield B J 
Published: February 2020

Abstract
A method has been devised for the detection of chlorodibenzo-p-dioxins in the presence of chlorobiphenyls, chloronaphthalenes, and chlorodibenzofurans. The chlorodibenzo-p-dioxins are chlorinated to octachlorodibenzo-p-dioxin, which is then identified by electron capture gas-liquid chromatography. 2,3,7,8-Tetrachlorodibenzo-p-dioxin has been determined in corn oil at the 1 ppm level.
Study of the Silicic Acid Procedure of Armour and Burke for the Separation of Polychlorinated Biphenyls from DDT and Its Analogs
Authors: Masumoto Herbert T 
Published: February 2020

Abstract
The silicic acid procedure of Armour and Burke for the separation of polychlorinated biphenyls from DDT and its analogs produces an adequate separation of Aroclor 1260. However, the procedure cannot completely separate p,p′-DDE from Aroclors 1221, 1232, 1242, and 1254. Factors causing variable column properties were examined. The 7 hr minimum period for silicic acid activation was found to be inadequate for reproducible water-silicic acid preparations. A 24 hr minimum period is suggested. The use of Celite in column preparation often results in improperly prepared columns and should be eliminated. Nonreproducible columns might also be due to a heterogeneous water-silicic acid adsorbent which is a result of an irregular distribution of water molecules on to the silicic acid particles.
Precision and Accuracy of Infrared Milk Analysis
Authors: Biggs D A 
Published: February 2020

Abstract
Estimates of precision and accuracy of milk analysis by the IR method are reported for comparison studies done at the University of Guelph, the Ontario Central Milk Testing Laboratory in Guelph, the British Columbia Department of Agriculture Laboratory in Vancouver, B.C., and the Dairyman’s Cooperative Creamery Association in Tulare, Calif. The standard reference methods used were: the Mojonnier method for fat, a semimicro Kjeldahl method for protein, a polarimetric method for lactose, the USDA lactometer method for solids-not-fat, and the AOAC method for total solids. Mean differences of 0.01 or less and standard deviations of difference between means of duplicate tests of the order of ±0.03 have been reported for fat, protein, and lactose; whereas, for solids-not-fat or total solids, mean differences have been about 0.015% and standard deviations of difference about ±0.09%. Best results have been obtained when calibrations have been routinely checked with a reference standard method, and have been adjusted when accumulated calibration data showed either the slope or level calibration to be in need of adjustment. Since the IR method essentially reproduces the results which would be obtained by the standard analytical method used for calibration of the IR instrument, significant differences between the results produced by different laboratories with standard methods will cause significant differences between the IR results produced by the same laboratories. This has been substantiated by the results of a collaborative study in which 5 pasteurized homogenized and 5 raw milk samples were analyzed by both standard and reference methods at the above mentioned laboratories and at Ross Laboratories in Columbus, Ohio. Although regression analysis showed that the calibrations at the various laboratories were producing good estimates of the standard values, there nevertheless were statistically significant differences between the mean values produced by these laboratories for both the standard and IR methods. The IR milk analyzer method for the analysis of milk has been adopted as official first action.
Collaborative Study of the Spectrophotometric Determination of Phosphatase Activity in Milk Utilizing a New Alkaline Phosphatase Assay System
Authors: Kleyn D H , Huang C L 
Published: February 2020

Abstract
A quantitative procedure (modified new method) has been studied that employs phenolphthalein monophosphate as the substrate and dialysis of released phenolphthalein followed by subseqvient measurement of the dialysate in a spectrophotometer at 550 nm. Nine collaborators evaluated 6 unknown samples of milk containing various levels of rawmilk, in triplicate, by the modified new method and the Scharer modified spectrophotometric method. Analysis of variance revealed that the random error of the modified new method was almost twice that of the Scharer technique, while the systematic error of the modified new method was only about ¼ that of the latter method. Two-sample charts indicated that the systematic error of the modified new method was less than that of the Scharer method; this was verified by a statistical comparison which showed that the total analytical error was much lower for the modified new method. A linear relationship was found between the 2 methods by 5 of the collaborators; the correlation coefficients ranged from 0.993 to 0.999. Based on these results, the method has been adopted as official first action for the analysis of milk.