bluuebunny/crossref_metadata_2025 huggingface dataset:
Design of Piston Gauge Verification Data Processing System Based on LabVIEW
Authors: Yao Cui Yao , Sun Bo , Guang Liu Hong , Wang Zhe
Published: February 2020

In order to check the weight of the quality of piston and its connecting parts more conveniently, this paper designs a set of data processing system for piston gauge measurement and verification based on LabVIEW. The system uses LabVIEW development platform to establish a visual human-machine interface. According to the requirements of JJG59-2007 National Verification Regulation of Piston Pressure Gauge, a set of data processing system is designed and completed. The system can accurately and effectively calculate the special weights of Special Weight, Piston and Connecting Parts of Piston Gauge according to the verification data. It greatly improves the work efficiency. The research lays a foundation for adding piston position indication device and automatic generating and exporting of original records in the system.
Longitudinal Protection of LCC-VSC Bipolar HVDC Transmission Line Based on Model Identification and Current Polarity
Authors: Dan NIU , Shuping GAO , Guobing SONG , Chu ZHANG , Huanfei YE
Published: February 2020

For hybrid bipolar DC transmission systems, combined with model identification and current polarity, a new principle of longitudinal protection of transmission lines is proposed. This paper analyzes the fault network and finds: when the front end of the inverter side fails, the fault model is equivalent to the C model, and when the back side of the inverter side fails, the fault model is equivalent to the RL model; when the front end of the rectification side fails, the rectification side fault current has a positive polarity, and when the rectification side back side fails, the rectification side fault current has a negative polarity. In conclusion, DC line area failure, namely the inverter side front and rectifier side front fault at the same time, the fault model matching C model, there was a positive polarity fault current at the same time; Failure occurs outside the DC line area, namely the inverter side front and rectifier side front no fault at the same time, inverter side failure model does not match the C model, or rectifier side fault current with a negative polarity. This new principle compensates for primary protection and can be used as an improvement to backup protection.
An Alternative Method for GIS Insulation Performance Evaluation
Authors: Lin Wu Song , Xiao Bo , Hu Min , Yao Yong , Fu Wei , Zhang Haiyan
Published: February 2020

The continuous improvement of system capacity and voltage level is somewhat accompanied by insulation fault as one of the main faults of GIS device. In this paper, an alternative method for identifying the GIS insulation performance based on fuzzy evidence theory is proposed by way of judging the four main features of GIS insulation level. Firstly, the fuzzy statistic test was used to obtain the normalized values of the four feature quantities of GIS insulation level. Four methods were used to calculate their respective expectations and deviations. The membership degree value was determined by the membership function, and the difference between the membership degrees was also considered. The degree of fusion was used to determine the weight of each feature quantity, so that the membership degree of the same kind of feature information fusion was obtained. Finally, the merged membership degree was transformed into the basic trust distribution function. The evidence theory then took the job to realize the pairwise fusion of the trust distribution functions between different feature quantities. The experimental results showed that this alternative way was proven to make effective judgment on the GIS insulation performance.
Advantages and limitations of a supernegative GFP in facilitating MyoD intracellular tracking
Authors: Boeri Lucia , Jacchetti Emanuela , Soncini Monica , Negro Alessandro , Albani Diego , Raimondi Manuela Teresa
Published: February 2020

Despite intracellular molecular dynamics being fundamental to understand pathological, biomechanical or biochemical events, several processes are still not clear because of the difficulty of monitoring and measuring these phenomena. To engineer an effective fluorescent tool useful to improve protein intracellular tracking studies, we fused a supernegative green fluorescent protein, (−30)GFP, to a myogenic transcription factor, MyoD. The (−30)GFP-MyoD was able to pass the plasma membrane when complexed with cationic lipids. Fluorescence confocal microscopy showed the protein delivery in just 3 hours with high levels of protein transduction efficiency. Confocal acquisitions also confirmed the maintenance of the MyoD nuclear localization. To examine how the supernegative GFP influenced MyoD activity, we did gene expression analyses, which showed an inhibitory effect of (−30)GFP on transcription factor function. This negative effect was possibly due to a charge-driven interference mechanism, as suggested by further investigations by molecular dynamics simulations. Summarizing these results, despite the functional limitations related to the charge structural characteristics that specifically affected MyoD function, we found (−30)GFP is a suitable fluorescent label for improving protein intracellular tracking studies, such as nucleocytoplasmic transport in mechanotransduction.
Phase composition and dielectric properties of spark plasma sintered PbZr0.52Ti0.48O3
Authors: Gupta Abhishek Kumar , Sil Anjan
Published: February 2020

In the present work, lead zirconate titanate PbZr0.52Ti0.48O3 (PZT) bulk ceramic powders having composition aimed for morphotropic phase boundary (MPB) were synthesized by conventional solid-state reaction and sintered by novel spark plasma sintering (SPS) method. The samples sintered at four different temperatures of 800, 850, 900 and 950 °C are found to have almost same density. The effect of SPS temperature on microstructure, phase constituents and dielectric properties is investigated. Rietveld refinement of XRD patterns of samples was carried out to estimate the phase composition revealing that the enhanced dielectric response is due to the presence of monoclinic phase along with the tetragonal phase in the synthesized material. The maximum room temperature dielectric constant ε
r ∼950 was found for the sample sintered at 900 °C. It is observed that the temperature has a significant role in resulting change of phase composition and dielectric performance of all the samples due to sublimation of PbO content.
Hybridization fluctuates with rainfall in Darwin’s tree finches
Authors: Kleindorfer Sonia , Dudaniec Rachael Y
Published: February 2020

Hybridization in natural populations may be an adaptive response to shifting climatic regimes, but understanding this can be limited by the timing of sampling effort and confident identification of hybrids. On the Galapagos Islands, Darwin’s finches regularly hybridize; the islands also show extreme annual variation in rainfall, but the effect of annual rainfall on the frequency of finch hybridization is little known. Across a 20-year period on Floreana Island, we compare patterns of hybridization in sympatric Darwin’s tree finches (N = 425; Camaryhnchus spp.) and test for an effect of annual rainfall on (1) the frequency of hybrids (C. pauper × C. parvulus) and (2) the percentage of male hybrid birds produced per year (hybrid recruitment). Annual rainfall correlated with recruitment positively for hybrids, negatively for C. parvulus and not at all for C. pauper. Furthermore, the percentage of hybrids (range: 12–56%) and C. parvulus did not change with sampling year, but the critically endangered C. pauper declined. Our findings indicate that hybrid recruitment is recurring and variable according to annual rainfall in Camarhynchus Darwin’s finches.
Contemporary Mythopoiesis: the role of Herodotus in Neil Gaiman’s American Gods
Authors: Zajko Vanda
Published: February 2020

This article explores Neil Gaiman’s transmedial work American Gods as an example of contemporary mythmaking. Published in novel form in 2001 and launched as a television series in 2017, American Gods provides a commentary on the connectedness between different systems of stories and on myth itself as a vital present-day cultural form. It also provides us with a model for repurposing ancient material without reproducing the traditional hierarchies associated with cultures of storytelling. Gaiman’s text is an interesting case-study from the perspective of classical reception because he sidelines the ancient Greek gods in the main body of his story, while simultaneously positioning the ancient historian Herodotus as a significant intertext. The process of evaluating different cultures often veers between analyses which focus on similarities manifested across place and time and those which espouse a form of cultural relativism, a ‘live and let live’ philosophy. Gaiman seems to be offering something else here, namely a more vital and connected model for co-existence, one which is moving towards a pluri-versal perspective that acknowledges the links between political power, knowledge, and identity.
Determination of Hydroxyzine Hydrochloride in Commercial Feeds
Authors: Tuttle L P , Schall E D
Published: February 2020

Commercial feed samples containing 4, 6, and 8 ppm of added hydroxyzine hydrochloride were given a preliminary treatment and then analyzed by nephelometric, spectrophotometric, and polarographic techniques. The feeds included medicated and nonmedicated poultry rations, medicated swine feeds, and cattle supplements. The average recovery of the tranquilizer from the feed was 94.0, 97.8, and 95.6% by the nephelometric, spectrophotometric, and polarographic methods, respectively.
Determination of Dimetridazole in Feeds by D.C. Polarography
Authors: Daftsios A C
Published: February 2020

1,2-Dimethy1-5-nitroimidazole (dimetridazole) is most effectively analyzed by polarography. A portion of feed (usually 5 g) is extracted with methanol. An aliquot is evaporated to dryness, and the residue is dissolved in a solvent to be polarographed. The solution is passed through an alumina column and the eluate is polarographed at the dropping mercury cathode versus a mercury pool. The method is simple, fast, and accurate. Average recovery was 99.5%; standard deviation, 0,98.
Piperazine in Feeds
Authors: Payfer R
Published: February 2020

Foucry’s colorimetric method of analysis, suggested by Cavett and Heotis for the analysis of piperazine in feeds, was studied collaboratively this year in mash and pellets. Early results show that the method can be used for the analysis of piperazine in pelleted feeds; however, there is larger variation than expected and the study of this method should be continued.
Rapid Determination of Guthion Residues on Crops
Authors: Cox William S
Published: February 2020

Collaborative study was made of Bluman’s short method for the determination of Guthion residues stripped from fruits and vegetables, based on conversion of Guthion to anthranilic acid, diazotization, and coupling with N-1-naphthylethy lenediamine dihydrochloride. Residues were recovered from eight crops “spiked” at sub-tolerance levels (0.3—1.6 ppm). Seven of eight collaborators obtained recoveries of 53—137% at levels below 1 ppm and of 62—102% at levels above 1 ppm.
Procedures for Residues of Dinitro Compounds
Authors: Boggs H M
Published: February 2020

Six dinitro compounds, all either phenols or their salts, were studied in a survey of various types of procedures. The paper chromatographic method proposed in 1959 remains the best method for differentiating between these compounds and providing at least semiquantitative determination.
Determination of Particulate Matter and Alkaloids (as Nicotine) in Cigarette Smoke
Authors: Ogg C L
Published: February 2020

A collaborative smoking study for the determination of particulate matter and nicotine deliveries of cigarettes, by a method chosen by the Analytical Methods Committee of the Tobacco Chemists’ Conference, was completed during the year. The 12 collaborators obtained coefficients of variation within laboratories of 4% and between laboratories of 10%. Each collaborator was asked to smoke 40 cigarettes (8 samples of 5 cigarettes). Non-filter (85 mm) cigarettes and filter (85 mm) cigarettes were analyzed. The cigarettes were conditioned for 24 hours at 75°F and 60% r.h. prior to selection for smoking. Cigarettes weighing within 20 mg of the average cigarette weight (50 randomly selected cigarettes) were marked to a 30 mm butt length. The cigarettes were smoked into a Cambridge filter holder by an automatic smoking machine which drew a 35 ml puff of 2-second duration once every minute. Five weight-selected cigarettes, marked to 30 mm butt, were smoked per Cambridge filter and the particulate matter (wet) was determined as the weight gain of the Cambridge filter. Nicotine delivery was determined by distilling the Cambridge filter pads and measuring the nicotine spectrophotometrically.
Antioxidants (BHA and BHT) in Breakfast Cereals
Authors: Takahashi David M
Published: February 2020

A mixture of butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) in cornflakes was analyzed by gas chromatography. BHA and BHT were extracted from ground cornflakes directly with redistilled petroleum ether, filtered, concentrated, and injected. Recoveries of added amounts at levels of 0.5—50 ppm ranged from 83 to 120% for BHT, and 89 to 104% for BHA. BHA and BHT were distinctly separated from each other. Further study on cornflakes and other breakfast cereals is recommended.
Alginates in French Dressing
Authors: Wkier Oscar
Published: February 2020

A collaborative study for the detection of alginates in french dressing gave satisfactory results. The method involved precipitation of alginates with acetone-alcohol, removal of oil with dioxane, decolorization with Celite 545, and development of color with ferric hydroxide-sulfuric acid reagent. The method is recommended as official, first action for french dressing.
Diastase in Honey: The Schade Method
Authors: White Jonathan W
Published: February 2020

Limited collaborative study of the Schade method for determination of diastase in honey indicates need for further examination of the procedure. Because diastase determination is used in quality control of export honey, the 1963 collaborative samples were analyzed by the Institut fur Honigforschung, Bremen, Germany, by their version of the Schade method. Slightly lower values were obtained.
Determination of Ethoxyquin in Feeds
Authors: Gordon Richard S , Conkin Robert A , Machlin Lawrence J
Published: February 2020

Revisions were made in the official, first action method for ethoxyquin in feeds which reduce the blank to the 0— 4 ppm range without reducing the recovery of the antioxidant by more than 5— 10%. Furthermore, the method also is applicable to feeds stored a reasonable length of time under moderate conditions. Blind samples can be spotchecked with a precision of 10— 12% over the range of ethoxyquin expected in feeds. The method can be refined to yield a precision of 2— 3%, if desired for use in production control, by preparing a calibration curve from data obtained by using the method to determine known amounts of ethoxyquin added gravimetrically to a standard feed.
Contact Angles as a Measure of Surface Wetting Properties in Filth Flotation Analysis
Authors: Yakowitz Maryvee G , Eisenberg William V
Published: February 2020

A study was made of the surface wetting properties exhibited by insect fragments, animal hairs, and food particles in contact with oil and aqueous solvent systems used in oil flotation analytical procedures. The differential wetting phenomena involved in flotation separation procedures of both untreated and preliminarily treated materials can be studied by contact angle measurements, which provide valuable information about the degree of wettability and flotability of both filth and plant particles. The solid specimen material is immersed in an inverted position in the aqueous plase, and the applied oil droplet competes with the aqueous phase for "wetting" the solid. The contact angle is measured at the point where the oil droplet, the aqueous phase, and the solid surface meet. The instrument used for measuring contact angles and the accessory apparatus devised for the addition of oil droplets to inverted specimen mounts while immersed in aqueous media are illustrated.
Determination of Strontium-90 in Foods by the Di-(2-ethylhexyl) Phosphoric Acid (HDEHP) Method
Authors: Davis Sidney , Arnold Alphonso
Published: February 2020

A method has been developed for routine surveillance of strontium-90 in foods in which HDEHP extraction is used to separate yttrium-90 from the Sr-90. The counting technique is the same as that in the Harley method. Yttrium carrier is added to correct for losses, to make the method suitable for routine analysis. Average recovery from spiked pre-1945 food ash was 100.4%. There is no statistical difference in effectiveness of extraction between pH 1.1 and 1.5. Strontium-90 is quantitatively separated from yttrium-90. The proposed HDEHP method was compared with the Harley method. It was found to be an adequate substitute for surveillance studies, and saves considerable time.
Spectrophotometric Determination of Aluminum, Iron, Manganese, Phosphorus, and Titanium in Liming Materials
Authors: Chichilo P
Published: February 2020

Methods have been developed for the determination of aluminum with ammonium aurintricarboxylate (Aluminon); iron with 2,4,6-tripyridyl-s-triazine (TPTZ); manganese by oxidation to permanganate with KI04; phosphorus by a heteropoly blue method; and titanium with disodium-1,2-dihydroxybenzene-3,5-disulfonate (Tiron), Detertested are carried out on the filtrate obtained in the AOAC perchloric acid method for silicon. Adequacy of the directions was established by “ruggedness tests,” and the procedures were used to analyze carbonate and silicate liming materials. It is recommended that the methods be studied collaboratively.
The Oxidative Conversion of Thimet to Its Oxygen Analog Sulfone
Authors: Blinn Roger C
Published: February 2020

A qualitative and quantitative evaluation was made of the ability of twelve oxidants to convert Thimet Systemic Insecticide to its oxygen analog sulfone. Thin-layer chromatographic and infrared spectrophotometric techniques were utilized for this purpose. The superiority of m-chloroperbenzoic acid as the oxidant of choice is demonstrated.
Measurement of Residues of Cygon Insecticide and Its Oxygen Analog by Total Phosphorus Determination after Isolation by Thin-Layer Chromatography
Authors: Steller W A , Curry A X
Published: February 2020

A total phosphorus method incorporating thin-layer chromatographic isolation is described for the determination of Cygon Insecticide (generic name, dimethoate) and its oxygen analog. Residues of the insecticides are extracted from macerated plant tissue, and the extract, after solvent partitioning and concentration, is spotted on a thin-layer chromatographic plate. After development of the plate, the areas corresponding to the two compounds are scraped and eluted. The phosphorus content of the respective eluates is determined by an improved molybdenum blue method, and concentrations of dimethoate and its oxygen analog in the original samples are calculated.
Determination of Chlorinated Pesticide Residues in Fat by Electron Capture Gas Chromatography
Authors: Mccully K A , Mckinley W P
Published: February 2020

A general screening method has been developed for the cleanup and estimation of chlorinated pesticide residues in fats and oils. The fats were dissolved in benzene-acetone (1 + 19) and then precipitated at — 70 °C. The precipitated fat was removed by filtration through a column of Darco G-60 and Solka Floe in a jacketed filtering funnel. The filtrate was concentrated to a standard volume and an aliquot was analyzed by electron capture gas chromatography. With the exception of a few pesticides in butterfat and aldrin in beef fat, recoveries were 81 to 112% after a mixture of 12 chlorinated pesticides had been added to the fats prior to precipitation.

A Pyrex gas chromatographic column containing a 10% stationary phase of mixed silicones (4% SE-30 methyl silicone + 6% QF-1 fluoro silicone) was used to resolve this pesticide mixture. The compounds eluted from the column in the following order: lindane, heptachlor, aldrin, Telodrin, heptachlor epoxide, p,p’-DDE, dieldrin, o,p’-DDT, Rhothane, p,p’-DDT, endrin, and methoxychlor.
Identification of Grape Varieties
Authors: Rice A C
Published: February 2020

A series of grape juices and concentrates were diluted with Macllvaine’s buffer at pH levels ranging from 2 to 8 and analyzed spectrophotometrically. The relationship of various Concord and California grape juice samples from different geographical areas were characterized individually and in combination. The spectral characteristics of Concord and Salvador grape juice were found to be similar except at pH 7, where the Concord curve has two peaks (583 and 450 mμ) and the Salvador curve has only one. The anthocyanin components in Concord grape juice were studied chromatographically for an explanation of its unique spectral response at pH 7. Results are incomplete, and further study is recommended.
Iodine-131 in Foods
Authors: Velten Richard J
Published: February 2020

Two collaborative studies have been conducted on the determination of 1-131 in milk. In the first study, eight collaborators analyzed four samples ranging from 58 to 227 pc/L 1-131, but results were inconclusive. In the second study, 15 collaborators reported results for two samples. Results were much better. A third study is planned, on the basis of which a method will be proposed for adoption.
Colorimetric Determination of Oxyphenisatin and Oxyphenisatin Diacetate in Pharmaceutical Preparations
Authors: Major Antoine
Published: February 2020

A method is described which will quantitatively determine 0.1 mg oxyphenisatin or the diacetate in various pharmaceutical preparations. After removal of interferences by organic solvent extractions from aqueous solution and partition column chromatography, the reaction of oxyphenisatin (diacetate) with silver nitrate in alcoholic sodium hydroxide solution produces a violet solution, which follows Beer’s law (1—15 μg per ml). The method was satisfactorily applied to the assay of commercial tablets, liquids, and powders with recoveries, as per cent found of declared, in the range 95—101%.
Total Solids and Ether Extract in Fish and Other Marine Products
Authors: Risley H M
Published: February 2020

The first action rapid modified Babcock method for crude fat in canned fish (18.013) was again studied collaboratively. Two samples of fresh (unfrozen) fish were examined by 6 analysts in 3 different laboratories. The same fish (frozen) together with samples of canned tuna, canned salmon, and a mixture of raw sablefish and canned tuna were examined by a total of 12 analysts in 6 different laboratories. Each analyst also determined fat by the official acid hydrolysis method (18.012). The results show that the rapid modified Babcock method (18.013) has the same degree of reliability as the acid hydrolysis method; it has been rewritten for greater clarity following the suggestions of the collaborators, and the revised form is recommended for adoption as official, final action.
Malt Beverages, Sirups, Extracts, and Brewing Materials
Authors: Stone Irwin
Published: February 2020

A review is given of the collaborative work conducted by the committees of the American Society of Brewing Chemists for the two methods (sulfur dioxide in beer and hop acids by spectrophotiontometry) previously presented for adoption by the AOAC. Eight new methods have been accepted by the ASBC for publication and are in various stages of editorial completion.
Total Volatile Acidity in Wines
Authors: Gowans W J
Published: February 2020

The determination of the total volatile acidity of wines has been studied collaboratively, using modern equipment now available. Procedures studied employed the Cash Electric Still and conventional apparatus, an all-glass unit. Results were good on both types of apparatus and between collaborators. It is recommended that the method, using either type of apparatus, be adopted as official, first action.
Safflower Oil: Physical and Chemical Properties, and Fatty Acid Composition
Authors: Ibrahim Walld , Iverson John , Firestone David
Published: February 2020

Some physical and chemical properties, including fatty acid composition by gas chromatography, of 15 commercially refined safflower oils and three crude oils extracted from safflower seed, were determined. The average and standard deviations found were: refractive index, 1.4748 ± 0.0003; specific gravity, 0.9210 ± 0.0005; iodine number, Wijs, 143.4 ± 1.4; squalene, 7.1 mg/100 g ± 1.1; and Bellier test, 7.4° ± 0.9. The major fatty acid components were; palmitic 6.7 ± 0.3, stearic 2.7 ± 0.4, oleic 12.9 ± 0.6, and linoleic 77.5 ± 1.1. Minor fatty acid components detected were myristic, arachidic, and eicosenoic acids.
Protein Typing of Some Authentic Fish Species by Disc Electrophoresis
Authors: Mancuso Vivian M
Published: February 2020

Disc electrophoresis has been used to identify protein types of authentic fish species. Patterns are given for 22 varieties of fish, representing members of the Snapper, Grouper, and Weakfish families.
Colorimetric Determination of Nemacide and Ronnel in Animal Tissues
Authors: Claborn H V , Ivey M C
Published: February 2020

colorimetric method is described for determining Nemacide® and ronnel in the body tissues of sheep and cattle. After extraction and suitable cleanup, the insecticide is hydrolyzed and the resulting 2,4-dichlorophenol or 2,4,5-trichlorophenol is steam distilled. The phenols are reacted with 4-aminoantipyrine; the colored compound is extracted into a nitromethanepyridine mixture and the absorbance determined at 490 mμ. Recoveries of 88-95% are possible when known amounts of Nemacide are added to the tissues. The method will detect residues as small as 0.05 ppm of Nemacide, and preliminary tests indicate that it is equally sensitive for the determination of ronnel.
Analysis of Lipsticks. II. Chromatographic Separation of Castor Oil-Oleyl Alcohol Mixtures
Authors: Gross Frederick C , Newburger Sylvan H
Published: February 2020

Absorption chromatography with silica gel as the adsorbent was used to separate castor oil-oleyl alcohol mixtures, alone or in the presence of a lipstick base. Results show that oleyl alcohol can be eluted with isopropyl ether-isooctane (65+35) and castor oil with ethyl ether-isooctane (10+30). Identification was made through the infrared spectra of the residues from the eluates.
Reduction of Nitrates in Acid Medium with Raney Catalyst Powders
Authors: Brabson J A , Burch W G
Published: February 2020

Of several Raney catalyst powders (alloys of aluminum with other metals), the most efficient reduetant of nitrates in acid medium was that of Al and Ni; others, in decreasing order of reducing power, were Cu-Al, Ni-Cr-Al, Co-Al, and Fe-Al. In the reduction, nascent hydrogen, generated by the reaction of Al with the acid, is adsorbed on the alloying metal and there reduces the nitrate. A relatively small amount of the alloy is required, and the resulting salts do not interfere with subsequent Kjeldahling and distillation. The method was applied successfully to mixed fertilizers containing nitrates and to mixtures of potassium nitrate with organic materials that are occasional constituents of fertilizers. The method is suitable for solid and liquid fertilizers that contain considerable chloride.
Evaluation of Two Modifications of the Volumetric Ammonium Molybdate Method for Phosphorus
Authors: Hoffman W M , Woolson E A
Published: February 2020

Results are given on a collaborative study for total phosphorus, comparing two volumetric procedures with the “quimociac” modification of the gravimetric quinoline molybdate method. While the NPFI volumetric method seems to be capable of giving accurate phosphorus values its precision is not as yet acceptable; the technique of end point detection needs further study. A ruggedness test showed a significant difference between the use of 0.4 ml of phenolphthalein and electrometric titration to pH 7.85. The TVA volumetric procedure exhibited a trend to lower values than those by the QM method. Even though the differences between the methods are not statistically significant, this negative bias should be eliminated if possible. The results of the quinoline molybdate method further emphasize the recognized accuracy and superior precision of this method. The quimociac modification of the quinoline molybdate method warrants official, final action status.
Identification and Analyses of Five Organophosphate Pesticides: Recoveries from Crops Fortified at Different Levels
Authors: Storherr R W , Getz M E , Watts R R , Friedman S J , Erwin F , Giuffrida L , Ives F
Published: February 2020

The recoveries of five parent organophosphate pesticides from eight different fortified crops were determined hy a “gross” cleanup technique. The primary method of analysis. was GLC. Other determinative methods used for comparison were total phosphorus determination, paper chromatography, and determination of phosphorus esters with p-nitrobenzyl pyridine reagent. The five organophosphate pesticides studied as mixtures and individually were Diazinon, methyl parathion, parathion, malathion, and Trithion. The three fortification levels in crops were 5.0, 1.0, and 0.1 ppm.
Investigation of Two Gas Chromatographic Techniques for the Determination of Organophosphate Pesticide Residues
Authors: Giuffrida Laura , Ives Fred
Published: February 2020

Gas chromatography has been used in a recovery study for the development of a cleanup procedure for organophosphate pesticide residues in various crops. The effluent from one column was divided evenly between two detectors to obtain a dual analysis. A sodium thermionic detector, highly sensitive to phosphorus compounds, was used to give quantitative recovery data. A flame ionization detector was used to determine the efficiency of the cleanup.
Low Boiling Aromatics in Petroleum Fractions by Gas Chromatography
Authors: Klayder T J
Published: February 2020

A sensitive and very specific gas chromatographic method for low boiling aromatics in gasoline has been developed. A gas chromatographic column with Bentone 34 and Versilube F-50 gives an efficient separation of the aromatics. A heated, UV flow-through cell operated at 189.25 mμ shows good sensitivity with practically no interference from low boiling paraffins or saturated cyclic hydrocarbons such as cyclohexane.
Synthesis of Arsanilic-As74 Acid and Arsanilic-l-C14 Acid
Authors: Fredrickson R L , Bocchieri S F , Glenn H J , Overby L R
Published: February 2020

Arsanilic-As74 acid and arsanilic-l-C14 acid (p-aminophenyl arsonic acid) were synthesized in 20–30% yield with high radiopurity by way of the Bart reaction. Appropriately labeled p-nitrophenyl diazonium borofluoride and sodium arsenite were coupled, and the resulting labeled p-nitrophenyl arsonic acid was reduced to arsanilic acid by treatment with iron and hydrochloric acid. Purification procedures are described.
The Specificity of Di-(2-ethylhexyl) Phosphoric Acid (HDEHP) Method for Yttrium-90 in Foods: Modification for Fresh Heavy Fallout Conditions
Authors: Arnold Alphonso , Davis Sidney
Published: February 2020

Di-2-ethylhexyl phosphoric acid reagent from two commercial sources was investigated for a study of specificity of determining yttrium-90. Titration curves indicate no significant quantity of monoalkyl phosphoric acid ester, the only limiting impurity expected. The following radionuclides in pure solution were examined for removal of activity from yttrium-90: Ru-106/Rh-196, Zr-95/Nh-95, Ce-144/Pr-144, Ca-45, Mo-99, Zn-65, Cr-51, Fe-59, Ba-140/La-140, Cs-137, Nd-147/Pr-147. Both sources of reagent were highly effective in removal of activity of the introduced radionuclide. The removal of activity to within 0.1% of that initially introduced was demonstrated in all cases except the Ce-144/Pr-144 pair; in this case activity was reduced to within the 0.1% range by substituting a 0.1M HC1 wash for the normal wash at pH 1.4. Data arc included for the precision of the HDEHP method relative to picocuries of food ash analyzed and the standard deviation of the analysis.
New Penicillin G Working Standard: A Collaborative Study
Authors: Kirshbaum Amiel , Arret Bernard , Wilner Jerome
Published: February 2020

A proposed new penicillin G standard has been assayed collaboratively by eight laboratories. The mean “as is” potency obtained was 1642 u/mg with 95% confidence limits of 1631–1652 u/mg. On the basis of this study, the proposed standard has been adopted as the new official working standard.
Microbiological Assay for Bacitracin in Animal Feed
Authors: Craig G H
Published: February 2020

Eight samples of two types of bacitracin in broiler rations were assayed collaboratively by eight laboratories. One group contained 4, 6, 20, and 40 g of zinc bacitracin per ton; another group contained similar concentrations of bacitracin methylene disalicylate. Known amounts of bacitracin blended into feed were recovered: 80.5 and 71.9% from the 4 g/ton samples; 75.4 and 74.6% from the 6 g/ton; 101.0 and 102.2% from the 20 g/ton; and 97.3 and 97.0% from the 40 g/ton samples. Coefficients of variation of the assays were 29, 9 and 30.1% for 4 g/ton samples, 29.9% for 6 g/ton, 11.7 and 13.4% for 20 g/ton, and 11.0 and 11.8% for the 40 g/ton samples. The method is recommended for adoption as official, first action for samples containing 20 g/ton or more bacitracin.
Fluorometric Determination of Amprolium in Feeds
Authors: Szalkowski C R
Published: February 2020

A fluorometric method for the analysis of amprolium in feeds was studied collaboratively. The method is equivalent in sensitivity and reproducibility to the official AOAC method; however, bias is evident when antibiotics, except procaine penicillin and chlortetracycline, are mixed with amprolium. The method involves extraction with trichloroacetic acid; development of a fluorophor with sodium hydroxide, silver nitrate, and potassium ferricyanide; and measurement of fluorescence on a suitable photofluorometer. The method is applicable to feeds down to 40 ppm of amprolium.
Comparative Study of the Anthranilic Acid Esters by Ultraviolet Spectrophotometry, Colorimetry, Gravimetry, and Gas-Liquid Chromatography
Authors: Brunelle Richard L , Martin Glenn E , Ohanesian V G
Published: February 2020

A rapid and specific gas-liquid chromatographic method has been developed for the separation and quantitative determination of methyl and ethyl anthranilate in grape extracts and imitation grape flavors in the presence of interfering substances. Total methyl and ethyl anthranilate can be quantitatively determined in imitation grape flavors by ultraviolet spectrophotometry after steam distillation of the sample. Methyl and ethyl anthranilate show a characteristic peak at 335 mμ. Results for methyl and ethyl anthranilate by gas-liquid chromatography and ultraviolet spectrophotometry are compared with those obtained by the official AOAC methods.
Colorimetric Method for Determining Residues of Thimet (Phorate)
Authors: Winnett George , Katz Stanley E
Published: February 2020

A colorimetric method developed for Thimet eliminates many of the objectionable features of other methods currently in use. The procedure is fairly sensitive, requires little cleanup, and, except for minor alteration of standard laboratory glassware, requires no specialized equipment. Thimet and its metabolites are completely extracted from the plant material by chloroform, an aliquot is passed through a Florisil column, and the chloroform is evaporated. The residue containing Thimet and its oxidative products is picked up in a hexane-acetonewater system. The oxidized metabolites are removed by partitioning into the acetonewater phase. The hexane phase, containing Thimet, is evaporated to dryness and hydrolyzed with 48% hydrobromic acid. The hydrogen sulfide thus generated is determined colorimetrically as methylene blue.
Gas Chromatography of Unsaponifiable Matter. III. Identification of Hydrocarbons, Aliphatic Alcohols, Tocopherols, Triterpenoid Alcohols, and Sterols Present in Olive Oils
Authors: Eisner Jerome , Iverson John L , Mozingo Alfred K , Firestone David
Published: February 2020

Olive oils, both foreign and domestic, were saponified, and the unsaponifiable matter was fractionated on a Florisil column. Gas chromatography of the first two hydrocarbon fractions confirmed that squalene was the major component of pressed and solvent-extracted pomace oils. However, iso-and/or anteiso- tctratriacontane was the major hydrocarbon in olive kernel oil. Hydrogenation and temperature programming indicated that there were several homologous series present, consisting of normal, iso-and/or anteiso-, and multiple branched chain hydrocarbons. Gas chromatography of the third Florisil fraction (tocopherols, high molecular weight aliphatic alcohols, and triterpenoid alcohol components) indicated the presence of three homologous series of normal, iso- and/or anteiso-, and multiple branched chain alcohols. The triterpenoid alcohols were used to distinguish between pressed and solvent-extracted pomace oils. As little as 5% of pomace oil could be detected in laboratory-prepared mixtures. Campesterol and beta-sitosterol were the two sterols present in olive oils. The Fitelson test detected olive oils consisting entirely or largely of pomace oils.
The Determination of Mono-, Di-, and Triglycerides in Monoglyceride Concentrates by Column Chromatography
Authors: Distler E , Baur F J
Published: February 2020

A method for the quantitative determination of mono-, di-, and triglycerides was studied collaboratively. Samples are adsorbed on silica gel columns and the glycerides are separated by benzene, benzene plus 10% ethyl ether, and ethyl ether alone. Eight samples can be run simultaneously with an average standard deviation of 0.6–1.0%. Nine collaborators obtained average recoveries of 96, 100.3, and 102% for mono-, di-, and triglycerides, respectively.
Rapid Flame Photometric Method for Potassium in Fruit
Authors: Boland Frederick E
Published: February 2020

The flame photometric method of Pro and Mathers for potassium in wines and distilled spirits has been adapted to the analysis of sample solutions of fruit and subjected to collaborative testing. A sample solution of fruit is prepared and aspirated directly into the flame photometer. This eliminates the need for ashing the sample and thus saves time. Six Food and Drug Administration District Laboratories, two State Laboratories, and the Associate Referee participated in the collaborative study. The results indicated that the method is sufficiently accurate for the determination of potassium in frviits.
Chemical Composition of Red Sour Pitted and Sweet Cherries
Authors: Boland Frederick E , Blomquist Victor
Published: February 2020

Authentic data are presented on the composition of red sour pitted and sweet cherries.
Collaborative Studies on the Characterization of Lemon Juice
Authors: Yokoyama Henry
Published: February 2020

Analytical methods for determining the content of total amino acids and total polyphenolics in lemon juice are described and were adopted by the AOAC as official, first action. A procedure is also given for the determination of titratable acidity; further collaborative study will be conducted on the method.
Collaborative Study of Rotenone Methods
Authors: Rund Robert C , Hambleton Larry G
Published: February 2020

Samuel’s infrared procedure continues to show close agreement with the crystallization method. The ultraviolet procedure differed appreciably from the crystallization method and the question of acetone vs. chloroform as the extractant for powdered cube roots is raised. Results from 13 laboratories on 5 samples by the 3 methods are reported and evaluated. Continued study on each of the official, first action methods is recommended.
Collaborative Study of Chlordane by Spectrophotometric Method
Authors: Malina Marshall A
Published: February 2020

Chlordane reacts with a methanolic solution of diethanolamine and potassium hydroxide to form a wine-red product. The intensity of the color is proportional to chlordane concentration and is used as a specific quantitative measure of the assay of chlordane formulations. Eight laboratories made a collaborative study of this method on six formulations. These formulations included all the general types used: granular, dust, emulsifiable concentrates, and oil solutions. Results show that the method is reliable; the coefficient of variation is less than 5%. The method was adopted as official, first action.
Quantitative Determination of Phenylephrine Hydrochloride by Column Acetylation Technique
Authors: Clark William R , Rosenberg Lynn A
Published: February 2020

determination of phenylephrine hydrochloride in combination with other amine-type drugs. The mixture is placed on a sodium borate-Celite column and the nonphenolic amines are removed with chloroform. The phenylephrine remaining on the column is acetylated and removed with a chloroform wash. The acetylated phenylephrine is then saponified with alcoholic KOH and determined spectrophotometrically against standard phenylephrine at about 290 mμ. Recoveries averaged 98.5% with a range of 93.3–101.7%. Mean deviation from the average was 1.8%. The method was adopted as official, first action.
Analysis of Diphenylhydantoin and Phenobarbital Mixtures
Authors: Marino Victor S
Published: February 2020

Diphenylhydantoin and phenobarbital are separated by column partition chromatography using a favorable solvent pair with pH control. Both drugs are solubilized by 15% re-amyl alcohol in chloroform (mobile phase) while saturated trisodium phosphate solution (immobile phase) selectively traps phenobarbital. Spectrophotometry is used to determine both substances quantitatively. Average recovery results of nine collaborators are 101.46% for diphenylhydantoin and 100.46% for phenobarbital with respective average standard deviations of 1.10 and 0.30. The method was adopted as official, first action.
Piperazine in Drugs by Near Infrared Spectrophotometry
Authors: Mohn L
Published: February 2020

A method for the analysis of piperazine in drug formulations has been developed. The piperazine base, or its salt, is dissolved in water, and the solution is made strongly alkaline. The base is then extracted with chloroform and diluted to a definite volume, and the clear extract is examined by near infrared spectrophotometry. A collaborative study has been made this year on two authentic preparations. A mean recovery of 101.7% with a standard deviation of ± 0.99% was observed for a sugar sirup and a mean recovery of 100.9% with a standard deviation of ± 1.30% was observed for a powder. Collaborators report that the method is rapid, simple, and straightforward.
Determination of Nitrate in Feeds
Authors: Hatcher D W , Schall E D
Published: February 2020

Attempts to measure nitrate at the low levels found in feeds by existing methods failed due to interferences from the soluble organic matter extracted from the samples along with the nitrate. The difficulties increased as the nitrate level decreased. A method for low-level materials was developed in which nitrate was isolated from interfering substances by thin-layer chromatography, eluted quantitatively from the absorbent, and measured colorimetrically by a modification of the 3,4-xylenol method. The procedure will determine nitrate accurately down to 10 ppm or less.
Collaborative Study of a Method for Multiple Chlorinated Pesticide Residues in Fatty Foods
Authors: Johnson Loren Y
Published: February 2020

Twenty lahoratories took part in a collaborative study of a method for chlorinated pesticide residues in which gas chromatography is used for the quantitative measurements of the residues. Butterfat and evaporated milk were the sample products; heptachlor epoxide and dieldrin were the pesticides. The results of the study have the precision and accuracy expected of the method. The average recovery was 113% with a standard deviation of ± 0.039 ppm at the 0.29 ppm level for heptachlor epoxide, and 95.9% with a standard deviation of ± 0.052 ppm at the 0.26 ppm level for dieldrin.
Detection and Determination of Fumaric Acid in Foods
Authors: Smith H R , Gajan R J
Published: February 2020

A polarograph method for determination of funiaric acid shows promise and should be studied further.
Colorimetric Determination of Procaine Penicillin in Mixed Feeds
Authors: Stone Loyal R
Published: February 2020

Procaine penicillin is determined by a rapid colorimetric procedure based on conversion of penicillin to penicillamine which turns blue with arsenomolybdic acid reagent. The presence of other antibiotics and chemotherapeutic agents in the feed does not interfere. The method is suitable over the range 10–100 g procaine penicillin per ton of feed.
Sugar Determination in Green and Leafy Plants and Dried Forages
Authors: Potter Earl F , Long Marion C
Published: February 2020

The ion exchange resin method is superior for clarifying extracts of green and leafy plants and dried forages. The principal sugars present should be determined by the micro Shaffer-Somogyi method.
Determination of Trimethylamine Nitrogen in Extracts and in Volatile Fractions of Fish
Authors: Bethea Sammie , Hillig Fred
Published: February 2020

Dyer’s colorimetric procedure was applied to the determination of trimethylamine nitrogen (TMA-N) in distillates from frozen cod and frozen haddock. Studies show that a more accurate estimate of the TMA-N contained in fish is obtained when this colorimetric method is applied to the distillates rather than to the extract. The method is also shortened by the elimination of one distillation, two oxidations, and two titrations.
Dichlone Residues on Foods
Authors: Miller George A
Published: February 2020

A collaborative study was conducted to evaluate a colorimetric method for the determination of residues of the fungicide dichlone. The fruit or vegetable is stripped with benzene; the extract is cleaned up on an activated Florisil column and eluted with 1% acetone in benzene. The dimethylamine reaction product is then read spectrophotometrically. The results of 10 collaborators in the 0.5–4.0 ppm range were: peaches, 78–112%; tomatoes, 88–110%; strawberries, 80–105%. The method is rapid; sensitivity is 0.25 ppm. The method has been adopted as official, first action.
Determination of Sodium Cis-3-Chloroacrylate Residues in Cottonseed and Root Crops
Authors: Johnson D P , Stansbury H A
Published: February 2020

Residues of sodium cis-3-chloroacrylate are determined in cottonseed and root crops by measuring the color produced when the compound is reacted with pyridine and sodium hydroxide. It is extracted by first converting it to free cis-3-chloroacrylic acid and then blending the tissue with l-butanol. The extract is cleaned up by liquid-liquid partitioning of aqueous buffered solutions with ethyl ether and l-butanol, followed by chromatography on alumina. The method sensitivity is about 0.05 ppm and recoveries average 91.9 ± 1.6%. Residues ranging from 0.05 to 2.83 ppm were found in cottonseed from crops treated with 1.5–5 lb per acre. The hulk of the residue was in the lint-hulls-motes fraction of the seed; only 0.1–0.2 ppm was in the meal. Residues were not found in either the crude or refined oil. Both onions and potatoes were free of residues after treatment with up to 5 lb per acre. The half-life in soil was about 3 days.
Evaluation of Colorimetric Procedure for Dilan
Authors: Hansen Kenneth A
Published: February 2020

The colorimetric procedure of Jones and Riddick for Dilan has been modified and evaluated. It is specific, can be modified to be fairly sensitive, and is easy to perform. After further work to improve the cleanup, the method should be studied collaboratively.