bluuebunny/crossref_metadata_2025 huggingface dataset:
A Combination Carbon-Graphite Electrode for DC Arc Analysis
Authors: Mellichamp J. W. , Finnegan J. J.
Published: November 2005

A two-section electrode for d c. arc analysis is described. The crater section is amorphous carbon and the holder is graphite. In this way the advantages of the burning properties of amorphous carbon are obtained and the disadvantage of its poor machinability is largely eliminated The electrode found suitable for this adaptation is the cathode layer electrode which is used in a variety of analyses The two-section electrode requires no complex cutting tools and proper dimensions are easily maintained by the dimensional consistency of the carbon and graphite rods used in their construction A summary of test results is given in table form.
Infrared Spectra of Perfluorocarbon Derivatives of Sulfur Hexafluoride and Cyclic Nitrides
Authors: Halpern Ernest , Goldenson Jerome
Published: November 2005

The infrared spectra of 8 new fluoro-organic compounds are presented in the region from 2 to 15 microns Included are the spectra of cyclic nitrides and derivatives of sulfur hexafluoride Characteristic details of the spectra are discussed.
Statistical Evaluation of Spectrographic Methods
Authors: Nelson Benjamin N.
Published: November 2005

By using some of the excellent background material available from the literature, the tool of the statistically designed experiment is applied in the development and evaluation of spectrographic methods A preliminary design is carried through to determine the major factors affecting a method's total variability Further designs then study these gross variables in greater detail Eventually a reliable method, of known precision and bias, is developed, and the method is ready for routine use During the routine use, a quality control program is carried on to maintain a check on the results and yield a realistic estimate of variability over a period of time

The paper gives a bibliography of books and articles that the author has found particularly useful
The Determination of Uranium in Solution by X-Ray Spectrometry
Authors: Wilson Harry M. , Wheeler G. V.
Published: November 2005

A rapid, precise method for the determination of uranium in nitric acid solution is presented. The uranium in solution is excited by a primary x-ray beam from a molybdenum tube. The intensity of the uranium La, emission line is measured by means of a crystal spectrometer employing a scintillation counter and pulse height analyzer. This intensity is converted to concentration by relating to standard solutions

The modification of commercial equipment that simplified the solution analysis are described, as are comparisons of various instrument components.
The Spectrochemical Analysis of White Metals by the Point to Plane Spark Technique
Authors: Nausester Henry K.
Published: November 2005

A method for the spectrochemical analysis of white metals by the point to plane spark technique for the determination of major, minor and impurity elements is described Part one of this paper covers the common lead base alloys such as antimonial lead, typemetals, babbitts and solders. Part two deals with the common tin base alloys, namely babbitts and solders.
X-Ray Spectrography--Two Theta Values for EDDT
Authors: Fagel John E. , Madden Robert B. , Pikler Harold , Stephenson Harry T.
Published: November 2005

Two theta values for EDDT have been calculated and tabulated for wavelengths between 0 701 A and 8.735 A in the first through fourth orders.
Oscillographic Mass Spectrometric Monitoring of Gas Chromatography
Authors: Holmes J. C. , Morrell F. A.
Published: November 2005

A means of continuously monitoring the effluent from a gas chromatography column with a mass spectrometer and an oscilloscope is described. Any sixteen-mass-unit portion of a spectrum can be displayed and the smallest change in the pattern seen immediately. The scan rate can be altered so as to decrease the time required for the sixteen-mass-unit display, or to present a larger portion of the spectrum.

The method can be adapted to the study of such events as pyrolysis, reaction rate, thermal cracking, etc. The presence of intermediate compounds formed during a reaction can be detected quickly. These are only a few of the many uses to which a commercially available mass spectrometer may be adapted by means of this easily made modification which make it a more valuable tool where investigations of volatile materials are being made.
Spectrochemical Determination of Ferric Oxide and Silicon Dioxide in Alumina
Authors: Conrad Doris
Published: November 2005

A rapid and accurate spectrochemical method is presented for the determination of ferric oxide and silicon dioxide in alumina. This method is much more convenient than time-consuming gravimetric methods in which fusions are necessary for dissolution of the sample. The spectrographic method employs the use of finely divided germanium metal and graphite powder as buffers. The addition of germanium yields uniform, reproducible spectral lines. Data on the reproducibility of intensity ratios are included.
A Method of Monitoring Spectroscopic Sources
Authors: Bryan F. R. , Runge E. F.
Published: November 2005

A means of controlling spark excitation has been devised for the purpose of improving the accuracy of spectrochemical analysis. The system applies to currently popular air-interrupted sources regardless of the type of analysis being performed.

The control procedure consists of resolving and counting individual spark discharges to determine an exact discharge rate Previous control methods have depended on an ammeter and oscilloscope which neither indicate discharge rate accurately, nor resolve random irregularities in rate Reproducibility of the discharge rate can provide an improved means of repeating spectral line intensities as required for quantitative analysis.

The control system consists of a phototube pickup triggering an electronic scaling circuit Illumination from the spark discharge produces the phototube signal Individual discharges are counted to provide an indication of the exact spark discharge rate per unit time is used to determine the number of interruptions per half-cycle, and the ammeter reading assists in establishing proper primary input voltage in relation to breakdown potential of the air-gap.
The Spectrochemical Analysis of Corrosion Products on Lead Sheath of Cables
Authors: Bennett W. J.
Published: November 2005

A procedure for the spectrochemical analysis of lead samples, such as corrosion products of lead sheath is described. The powdered material is buffered with germanium dioxide and graphite powder and the resultant mixture pelletized. Multisource type discharges are used. Desired elements can be measured over a wide range of composition.
Correlations in Ultraviolet Spectrophotometry
Authors: Friedel R. A.
Published: November 2005

In the process of collecting a library of spectra of aromatic compounds for investigation of synthetic liquid fuels, various correlations have been observed. (1) Phenylnaphthalene-type spectra have been noted in related compounds, (2) spectra and structures of fluorene derivatives have been studied; (3) graphs of intensity as a function of wavelength for the first band in the spectra of several alkyl- and alicyclic-benzenes and phenols have revealed interesting properties; (4) spectral effect of three classes of alicyclic rings on the first band in spectra of polynuclear condensed aromatics have been discussed, and (5) ring-strain, produced by substituents in an aromatic nucleus because of steric hindrance, has been found to cause drastic changes in the spectra.
Comparisons of Spectra from Different Types of Mass Spectrometers
Authors: Caldecourt V. J.
Published: November 2005

A comparison of the cracking patterns of various compounds taken on different types of mass spectrometers shows large differences. Mass discrimination is a large factor, and this is to be expected, particularly when comparing 180° with 60° or 90° instruments. Variations because of the nature of the compounds are also evident.
Infrared Spectra of Some Biochemical Substances in Water
Authors: Parker Frank S.
Published: November 2005

Infrared spectra in water as a solvent are presented for some substances of biochemical interest, including members of the citric acid cycle. Use is made of a barium fluoride cell in conjunction with a transmittance screen. An example is given of the use of such spectra to show a chemical change attendant upon the dissolution of an unstable compound. The spectra of α-ketoglutaric acid in the solid state and in aqueous solution are given as examples showing typically distinct differences between spectra observed in water solution and in the solid state
Some Publication Trends in Spectroscopic Literature
Authors: Bryan Ford R.
Published: November 2005

Some simple statistics are derived from the ten-year bibliography of spectroscopic literature compiled by the Bell Telephone Laboratories and published in Applied Spectroscopy. The numbers of indexed articles are tabulated according to subject, year, and periodical in order to observe publication trends over the period including 1948 through 1957. Among the observations is strong evidence of the desirability of organized technical literature searching to obtain adequate coverage of the literature of spectroscopy.
A Study of Preliminary Curves for SA-I Emulsions
Authors: Green Milton
Published: November 2005

In some previous work we have found that for SA-II and 103F emulsions on film the logarithm of the density (log D) prelimininary curves are essentially straight lines. This experimental result leads to a rather simple and convenient expression for the equation of the characteristic curve. For SA-I emulsion on film, we found that the linearty of the log D preliminary curve depends considerable on the wave length region for which the measurements were made and the magnitude of the calibration intensity ratio employed, e.g. the step filter ratio.

A more careful analysis of preliminary curves of SA-I emulsions shows the reasons for such a behavior. Actually, the log D preliminary curves are always curved and the degree of curvature varies roughly in proportion to the product of the step ratio of the filter and the gamma at the wavelength at which the measurements are made Probably this same condition exists for SA-II and 103F emulsions, but because their gammas are low, the curvature is not readily observable with a step-filter of moderate ratio.

In spite of the curvature of the logD preliminary curve of SA-I emulsions, a straight line fits the data well for the useful range of density measurements for spectrochemical purposes, that is, for a range of densities corresponding to a range of transmittance values between 75% and 1%, the fit is nearly perfect.

In attempting to fit various analytical functions, theoretically derived by other investigators, to the erperimental data for SA-I emulsion for the wavelength range 4000A-4200A, it was found that the error function gives the best fit.
The Preliminary Curve Method of Plate Calibration When Densities of Spectral Lines are Measured in Seidel Values or Changed to Seidel Values
Authors: Strasheim A.
Published: November 2005

A procedure is described for the precise and convenient construction of preliminary emulsion calibration curves using Seidel values. The method employs the calculation of coordinate points representing averages of readings within specific Seidel unit intervals A standard deviation of 1.15% was obtained for gamma values on repetitive calibration exposures using the described preliminary curve construction techniques. The reading of galvanometer deflection directly in Seidel units is recommended for maximum efficiency.
The Spectrographic Determination of Potassium in Coal Ash
Authors: Rekus Andrew F.
Published: November 2005

Indium, which is relatively absent in coal, is described as the ideal internal standard for the determination of potassium in coal ash. The chemical composition of the coal ashes examined varied over considerable limits. The standard deviation was slightly less than % 6±. Indium is also suggested as a possible ideal internal standard for sodium determinations.
Determination of Sodium in Residual Fuel Oil Using A.C. Spark and Rotating Platform Electrode
Authors: Hullings Robert S.
Published: November 2005

An emission spectrographic procedure has been developed for the determination of sodium in residual fuel oil, using a.c. spark, excitation. The analysis is done directly on the oil using the rotating platform electrode technique. This technique may be used for the determination of sodium in the oil, as received, and also for very low concentrations, after the oil has been treated to remove the bulk of the sodium.
Spectrochemical Determination of Strontium-to-Calcium Ratio in Food, Milk, Cream, Blood Feces, and Urine of Cows
Authors: Shalimoff George V. , Conway John G. , Pitzer Ann E.
Published: November 2005

A d.c carbon-arc spectrochemical method has been developed for the determination of strontium-to-calcium ratios in the food, milk, cream, blood, feces, and urine of cows. In this method sodium is added to the samples to produce uniformly enhanced and reproducible spectral lines in the range of 10−4 to 5 × 10−2 strontium-to-calcium ratio. Typical examples of analyses of the food and products of three cows are included, with a precision of ±12%
Infrared Spectra of Xanthates and Related Compounds
Authors: Pearson F. Gardiner , Stasiak R. B.
Published: November 2005

Infrared spectra of Nujol mulls of several xanthates, oxyxanthates, and dixanthates are presented. Constancy of frequencies within each group is discussed, and correlation of these frequencies with molecular structure is attempted.
X-Ray Spectrographic Analysis of Nickel-Containing Alloys with Varied Sample Forms
Authors: Davis C. M. , Clark G. R.
Published: November 2005

Techniques are presented whereby x-ray spectrographic analyses are carried out on alloys and metallurgical products which enter the laboratory in the form of drillings, millings, or filings. The techniques described include direct analysis, with and without internal standards Analysis of high temperature alloys without a series of chemically analyzed standards by these techniques greatly extended the usefulness of the x-ray spectrograph.
The Internally Standardized Nujol Mull as a Method of Quantitative Infrared Spectroscopy
Authors: Bradley K. B. , Potts W. J.
Published: November 2005

The usefulness of the Nujol mull technique for quantitative infrared analysis of solids is often overlooked. When an internal standard is employed, the technique is accurate, generally applicable, and reliable Choice of internal standard, expermimental procedures, general accuracy, limitations, and specific examples of quantitative analysis are discussed.
Spectrographic Porous Cup Technique for the Analysis of Indium Alloys
Authors: Hyman Harry M.
Published: November 2005

A quantitative spectrographic procedure is described for the determination of the following alloying constituents in indium within the designated concentration ranges, silver (1.0 to 3 0%), gallium (0 1 to 2 0%), zinc (0 1 to 2 0%), and aluminum (0 1 to 1 0%) A porous cup solution technique is used with a c spark excitation and indium as an internal standard reference The accuracy of the method ranges from 4.0 to 8 3% of the amount found, depending on the element and concentration level of interest
A Semi-Quantitative Universal Method of Spectrochemical Analysis
Authors: Mohan P. V. , Fry D. L.
Published: November 2005

A semi-quantitative universal method of spectrochemical analysis designed for the determination of all metallic elements in powder samples has been calibrated for twenty elements The method uses lithium carbonate as a common matrix. It is accurate for many concentration ranges to within factors of 1/2 to 3/2 of the amount present Numerous variations of apparatus and conditions were investigated, with the results indicating that the deviations due to these factors were not large compared with the method error. The method may be improved in the future through a systematic investigation of sampling in the arc—the most likely source of error in the present method. Matrix effects, which were previously the greatest source of error, seem to have been largely overcome
Emission Spectrographic Determination of Metallic Impurities in Powdered Boron
Authors: Lader Seymour
Published: November 2005

A spectrographic method of analysis has been developed for the determination of eleven elements, in specified ranges, in powdered boron. Samples were converted to the oxide with H2O2 and nitric acid to permit the determination of greater percentages than those listed by proper dilution of the sample with pure boric oxide The method showed an average error of estimate of ±13 6% with a maximum of ± 16 6 and a minimum ±10 6 Samples from various manufacturers gave a coefficient of variation for the impurities ranging from 6% to 15%.
Long-Path Infrared Spectrocopy for Air Pollution Research
Authors: Stephens Edgar R.
Published: November 2005

A long-path absorption cell was developed for the measurement of gaseous contaminants in the atmosphere and for the studies of reactions of contaminants in the laboratory The instrument is based on the White multiple-reflection system, having two large spherical mirrors at one end of the 3-meter cell and one smaller one at the other end of equal radius.

To avoid excessive loss of radiant energy, the infrared source image is magnified and demagnified to match the cell to the spectrometer Optimum path-length for maximum signal is reached when reflection losses reduce the energy to 1/e of its initial value. CO2 and water vapor interfere with, but do not prohibit, useful analyses of the atmosphere

Two of these cells are in use, one in the Philadelphia laboratory and one in a field-study trailer in the Los Angeles area
A Three Stage Mass Spectrometer
Authors: White F. A. , Rourke F. M. , Sheffield J. C.
Published: November 2005

A three stage mass spectrometer, utilizing two consecutive magnetic focusing lenses of 20″ radii followed by a 20” radius of curvature electrostatic analyzer, is described An abundance sensitivity of 1010 was measured for this instrument in the low mass region. Application of this instrument to analytical and research problems in the field of mass spectrometry and results obtained are discussed.
A Digital Recorder for Mass Spectra
Authors: Caldecourt V. J.
Published: November 2005

As a mass spectrum, is scanned, the maximum value of each peak is stored in a capacitor Then the difference between the stored voltage and the lesser voltage seen after the scan has proceeded down the side of the peak operates a peak detector, which in turn initiates measurement of the stored peak height by a digital voltmeter At the same time the mass is determined by measuring the ion accelerating voltage with a modified self balancing potentiometer equipped with a shaft position digitizer.
Some Effects of Irradiation on an Air-Blast Spark Gap
Authors: Bryan F. R. , Runge E. F.
Published: November 2005

Effects of ultraviolet and radioisotope irradiation on the breakdown voltage of an air-blast gap have been measured. The type of gap selected for study simulates the control device incorporated in conventional spectrographic excitation sources. The effects of irradiation on the discharge characteristics of the air-blast gap were determined by exposing the gap to a quartz enclosed mercury arc and to the radiation from Radium D. There is found to be definite evidence that both ultraviolet and radioisotope radiations are effective stabilizers of gap breakdown voltage. The use of an irradiated air-blast gap should therefore be beneficial to precision spectrochemical analysis. The two types of radiation appear to be almost equally effective for this purpose.
Application of Nuclear Magnetic Resonance to Field Monitoring and Control in Mass and Alpha Energy Spectrometry
Authors: Sheffield James C. , White Frederick A.
Published: November 2005

Nuclear magnetic resonance instrumentation was applied to mass spectrometers in several arrangements of magnet field stabilization and control and as a monitor of the relative fields of paired magnet systems. Precise measurements of the magnetic field of an alpha spectrometer were made in determining alpha particle energies by monitoring the resonance frequency with an accurate frequency meter
Water Determination in Oil-Contaminated “Freon-12” by Infrared Spectrophotometry
Authors: Diamond W. J.
Published: November 2005

Modification of Benning's infrared method permits determination of water in Freon-12 refrigerant contaminated by as much as 1% oil. Quantity of oil is determined at the 2.34μ H band. The sum of water and the water equivalent value of oil is determined at 2 67μ. Difference between these two is the true moisture content of Freon-12®.
Ultraviolet Spectrophotometric Determination of 1,10-Phenanthroline
Authors: Secrest P. J. , Pawley J. A. , Lucchesi Claude A.
Published: November 2005

A method for determining the 1,10-phenanthrohne content of technical 1,10-phenanthrohne is described. The sample is dissolved directly in alcohol. The difference in absorbance of this solution at 323 5 mμ and 820 mμ is an approximate measure of the amount of 1,10-phenanthroline present. By differential comparison of a sample solution of technical 1,10-phenanthrohne with a reference solution containing a known amount of pure 1,10-phenanthrohne, a more exact determination can be made. Results obtained with the method were in close agreement with those obtained by a colorimetric method based on the formation of a red to orange complex by the reaction of 1,10-phenanthrohne with ferrous ions. The standard deviation of the method based on five duplicate determinations is less than 0.2%.
Theory of Thick Emulsions and the Kaiser Function
Authors: Arrak Arno
Published: November 2005

A mathematical theory of thick emulsions, based upon a previously published theorem, is developed. All important properties of the H and D curve and the Kaiser function are deduced and physical interpretations of the parameters of both functions are given. Deviations from Beer's law by a photographic emulsion are seen to be responsible for the occurrence of reciprocity failure phenomena. The occurrence of a reverse primary process is shown to be capable of invalidating the Poisson distribution of exposure.
Spectrographic Determination of Vanadium and Iron in Petroleum Coke
Authors: Vigler Mildred S. , Conrad Anne L.
Published: November 2005

A rapid spectrographic method has been investigated for the determination of vanadium and iron in coke, ranging in concentration from 0 001 to 0 05 percent The analysis was performed on the volatile-free coke previously powdered and dried by standard procedures. A spark-ignited, low voltage a.c arc was used to excite the sample and results agreed within ±10 percent with those obtained by the ASTM D-271 procedure Coefficients of variation were 12 8 percent for iron and 55 percent for vanadium The method is applicable to the simultaneous determination of many other metals
Slopes of Working Curves in Emission Spectrometric Analysis of Certain Silicates
Authors: Hurwitz J. K.
Published: November 2005

In the emission spectrometric analysis of silicates, Strock recently reported large deviations from unity of the working curve slopes He suggested that these abnormal slopes resulted from collisions of the second kind occurring in the direct-curent arc discharge. These experiments were repeated, and data were treated statistically. Deviations from a slope of unity in nearly every case were satisfactorily explained by the experimental errors inherent in the method or by self-absorption.
A New Infrared Spectrometer in the 12.5–25 Micron Region
Authors: Alpert N. L. , Behnke F. , Strauss P. A.
Published: November 2005

In order to extend wavelength region to 25 microns a Perkin-Elmer Infracord has been adapted for use with a KBr prism. Design of the instrument and its performance characteristics will be described Experiments have been performed to illustrate several classes of chemical problems for which the 12 5 to 25 micron region of the spectrum is particularly useful in solving Typical spectra are shown.
A Comparison of Carbon and Graphite Electrodes
Authors: Mellichamp J. W. , Finnegan J. J.
Published: November 2005

The electrode material in which the sample is excited is an important factor in spectrochemical analysis. While physical differences between carbon and graphite electrodes are found to be slight, a difference in consumption rates in a direct-current arc is observed. Thermal conductivity of the electrode material produces a temperature gradient which, along with arc conditions, determines electrode consumption rates. Selective volatilization of impurity elements as well as intensities of impurity spectral lines are modified by changes in consumption rates.
Accuracy in Spectrochemical Analysis
Authors: Arrak Arno , Mitteldorf A. J.
Published: November 2005

Accuracy is one of the broad areas of spectrochemical analysis where improvement by an order of magnitude would result in vast new fields of application. This paper discusses the subject under the topics of sampling, the source, electrodes, the spectrograph, photometry and calculations New techniques for reducing variables will be discussed These include optics for reducing the effects of arc wandering, the Elpac for reproducible packing of powders into electrodes, devices for mechanically traversing a flat sample during sparking, the Stallwood jet and enclosed arc chamber,
The Spectrochemical Analysis of High Purity Gallium
Authors: Owens E. B.
Published: November 2005

Gallium is separated from its impurities by solvent extraction of the HGaCl4 complex with isopropyl ether from 6–7 N HCl. Two extractions suffice to lower the Ga concentration to negligible amounts. The volume of the HCl phase after extraction is reduced and a measured portion dried on waxed graphite electrodes. The spectra are excited with a condensed spark and photographed. Maximum sensitivities reported are (parts impurity per million parts gallium). Al – .03, Ca – .03, Cr – .06, Cu – .015, Pb – .06, Mg – .015, Ni – .06, Zn -, 12. The coefficient of variation of measurement varies from 3.6% for Cu to 14.8% for Pb.
The Mass Spectra of Alkylindoles
Authors: Beynon J. H. , Williams A. E.
Published: November 2005

The mass spectra of 11 alkylindoles have been obtained Correlations between their structures and mass spectra are given and peaks characteristic of alkylindoles are discussed. The major fragmentation mode corresponds to cleavage of bonds β to the ring system, certain re-arrangement ions can be shown to be formed in a two-stage fragmentation process, the first stage involving β-bond cleavage and the second loss of the stable neutral fragment HCN. The stabilities of the fragment ions formed is suggested to add drive to some of the fragmentation processes observed and the possible structures of some of the ions are discussed.
Infrared Spectra of Metal Nitrates
Authors: Vratny Frederick
Published: November 2005

The spectra of 35 metal nitrates are presented A tabulation of observed absorption maxima is made and an interpretation of the spectra provided This is based on symmetry changes on the nitrate group, resulting from changes in the metal-to-nitrate bond The compounds are classified as to the degree of ionic or covalent character
Appearance Potentials as Obtained with an Analytical Mass Spectrometer
Authors: Lambdin W. J. , Tuffly B. L. , Yarborough V. A.
Published: November 2005

A method is presented for measuring appearance potentials with an analytical mass spectrometer. Slight modifications of the ion source and a unique method of interpreting ionization efficiency curves produce values which are generally accurate to within 0 5 per cent. Electron energy in the bombarding beam is partially controlled by a grid The differential ion current due to a small change in ionizing potential is recorded and the interpretation produces efficiency curves which approach the form which could be obtained with mono-energetic electrons Conventional use of the instrument is not affected by the modification Bond-strengths determined from data by this method are in good agreement with published data
A Variation of the Compensation Technique in Infrared Spectrophotometry
Authors: Manno R. P. , Paraskevopoulos N. , Matsuguma H. J.
Published: November 2005

A novel variation of the classical method of spectral cancellation used with double-beam infrared spectrophotometers is presented The technique described involves the simultaneous utilization of both beams of a double-beam spectrophotometer to compare the spectra of chemically related but not identical substances The results of preliminary studies, and quantitative application of this new technique, are described
The Spectrochemical Analysis of Super Pure Chromium for Impurities
Authors: Baird C. G.
Published: November 2005

A method is described for the spectrochemical analysis of super pure chromium for six impurity elements. The chromium is removed by volatilisation as chromyl chloride and the impurities collected on a calcium sulphate matrix. This is burned in a d.c. arc and the intensities of the impurity lines are measured with reference to indium, which is added as an internal standard. Working curves are shown for the six elements, Mg, Pb, Fe, Al, Cu and Ag in the concentration range 0.005 – 0.0001 per cent. Results are given of a typical analysis and the standard deviations.
Spectrophotometric Determination of Nickel with Mercaptoacetic Acid
Authors: Christopher Philip C. , Hamme Harry W.
Published: November 2005

A new method for the determination of nickel with mercaptoacetic acid is described. The method is sensitive down to 0.001 mg nickel per ml of solution and Beer's law is followed up to concentrations of 0.7 mg per ml. The color is stable for several hours and the pH of the solution is not critical as long as it is in the alkaline range. Preliminary separation of nickel by the dimethylglyoxime extraction method eliminates interferences. Sodium citrate, when present in the solution before color development, prevents interference from metals extracted with the nickel during the separation and enhances the sensitivity of the method.
An Induced Percussion Electrode Packing Machine
Authors: Strasheim A. , Tappere E. J.
Published: November 2005

An induced percussion electrode packing machine is described Using this packer more material (on weight basis) can be packed into an electrode cavity than is possible by hand, or using a vibrational type packer. The amount of material packed into the electrodes depends on the size of the electrode cavities and weight of the plunger. For some materials the reproducibility of the amount of material packed is better than 1%. Electrodes packed with the machine give superior spectrochemical results when compared with results obtained when the electrodes are packed manually.
The Longest Wavelength Band in the Electronic Spectra of Polycyclic Aromatic Hydrocarbons for Analytical Use
Authors: Karr Clarence
Published: November 2005

A table is presented listing 408 polycyclic aromatic hydrocarbons, with three or more aromatic rings, according to increasing values in millimicrons of the longest wavelength absorption band. Structural formulas, the values in millimicrons of additional absorption bands, solvents, and literature references partly through 1958 are also given A procedure is recommended for utilization of this table in the spectrophotometric analysis of samples, such as those obtained in fractionation by elution chromatography.
Mass Spectra of Various Quinones and Polycyclic Ketones
Authors: Beynon J. H. , Williams A. E.
Published: November 2005

The mass spectra of anthraquinone and 21 substituted anthraquirtones have been obtained, together with those of three other quinones and two polycyclic ketones. The spectra are discussed both from the point of view of understanding the processes involved in the fragmentation of compounds containing keto groups and from that of being able to distinguish between various isomers and to identify unknown compounds m these classes.
The Spectrochemical Analysis of Bismuth Using a Photoelectric Spectrometer
Authors: Forrest Joseph , Finston H. L.
Published: November 2005

The Liquid Metal Fuel Reactor Program requires rapid, accurate analyses of large numbers of bismuth metal samples. A spectrochemical solution procedure using a rotating disc technique with a Baird-Atomic Research Direct Reading Spectrograph is described. Yttrium is added as an internal standard. Magnesium and zirconium are determined with a precision of 2% of the amount present; the precision for iron, chromium, manganese, nickel and molybdenum is within 4–12%.
Spectrographic Analysis of Indium Metal for Impurities
Authors: Hyman H. M.
Published: November 2005

A quantitative spectrographic method has been developed for the determination of eight impurity elements in indium within the range 0 0005–0 1%. The elements chosen are those considered to be of most probable occurrence and importance and are as follows; copper, gallium, iron, lead, nickel, silver, tin and zinc. The analytical method utilizes a high-voltage a.c arc excitation on a platform-centerpost electrode coated with dried sample salts. The method is versatile in that it can be extended to include higher, lower or other impurity element concentrations of interest. An over-all accuracy of approximately ±15% of the amount found can be expected.
Output Systems for Time-Of-Flight Mass Spectrometers
Authors: Betts J. F. , Paufve E. H. , Wiley W. C.
Published: November 2005

The three major types of output systems for time-of-flight mass spectrometers are described and their applications discussed. An oscilloscope output system is used to obtain quick answers with accuracy being limited to the accuracy of the oscilloscope employed For very small mass peaks, accuracy degenerates to zero. An analog output system is considered to be the most useful and versatile output system. It uses a selective gated input to measure simultaneously the areas under several mass peaks. Using this type of output, spectral patterns which are normally generated in several miscrosec can be recorded on recorders with a response of 100 cps or less. When the average number of ions per mass peak per mass spectrum is considerably less than one, a counter circuit (digital output system) can be used to totalize the ions which occur in specific mass peaks. Several mass peaks can be counted simultaneously
Direct Reading Spectrometric Determination of Zinc, Copper and Lead in Plant Material
Authors: Strasheim A. , Eve D. J.
Published: November 2005

A method is described for the direct reading spectrometric determination of zinc, copper and lead in plant material. The metals to be determined are separated by dithizone extraction from a solution of 1 gram of the plant material. The excitation source consists of an interrupted d c. arc struck between a graphite counter electrode and a rotating graphite-sodium carbonate disc, on to which a chloroform solution of the metal dithizonates is sprayed. Spectrum line emission measurements are made by means of a medium dispersion quartz prism spectrograph with direct reading attachment A series of plant material samples has been analysed by the method and the standard deviations of the results obtained from the mean of two arcings in each of ten replicate analyses were found to be 5.1% for zinc, 73% for copper and 61 % for lead.
Theory of the Accuracy of Wedge Density Matching of Logarithmically Sectored Spectra
Authors: Green Milton
Published: November 2005

An elementary theory on the accuracy of wedge-density matching for logarithmically sectored spectra is given The results of the theory show that, other things being equal, the fractional error, as a result of wedge-density matching, in the measurement of intensity ratios of line pairs varies inversely as the intensity scale gamma of the emulsion employed, and within limits, is independent of both the magnification of the spectrum and the sector constant.
Characteristic Infrared Frequencies of 3,3-Diphenylphthalides in the Region of 2000 to 330 Cm−1
Authors: Jakobsen R. J. , Wyant R. E.
Published: November 2005

The infrared spectra of ten 3,3-bis(phenyl)-phthalides were obtained in order to select frequencies characteristic of the phthalide ring system, and to observe the effects of phenyl substitution in the 3 position of the phthahde ring system. Bands characteristic of the phthahde ring system per se were observed near 1284 cm−1, 1107 cm−1, 1016 cm−1, 503 cm−1, and 479 cm−1. Bands characteristics of 3,3-bis (phenyl)-phthalides were seen near 632 cm−1, 530 cm−1, and 370 cm−1. The effect of substituents on the 3,3-phenyl rings upon frequency was noted for several bands, bands characteristic of these substituents were also observed These data indicate that the various bands can be used for identification of the 3,3-bis(phenyl)-phthalide structure.
Spectrographic Analysis of Air Samples for Beryllium Contamination
Authors: Brash M. P.
Published: November 2005

A spectrographic technique for the determination of beryllium in atmospheric dust has been developed. Both a permanently installed low volume air sampler and a portable high volume sampler are employed for obtaining the air-borne dust samples. Solutions of the filtering media are used for spectrographic analyses, by a solution-spark technique using a rotating disk electrode The method is sensitive to 0 05 micrograms of beryllium per cubic meter of air, with a coefficient of variation of less than 11% in the 0 5 to 2 microgram range.
Some Industrial and Biological Applications of a Recording Reflectometer
Authors: Anacreon R. E. , Noble R. H.
Published: November 2005

Data are presented which have been obtained on a spectrophotometer with a diffuse reflectance accessory. These data include reflectance records with or without specular rejection. Tristimulus values are computed from certain records to show similarity to results from other instruments. Close agreement has been found Transmission measurements and scattered light measurements on turbid samples are also demonstrated
Spectroscopic Analysis of Polyvinyl Chloride Compounds
Authors: Burley R. A. , Bennett W. J.
Published: November 2005

A quantitative procedure is described for the determination of plasticizer, resin, stabilizer, and filler in formulations based on polyvinyl chloride and polyvinyl chloride-polyvinyl acetate copolymers The plasticizer is extracted with ethyl ether, the resin is dissolved in tetrachloroethane, and the solution is centrifuged to remove the stabilizer and filler The infrared spectrum of the plasticizer is determined either on the recovered material directly or in solution in carbon disulphide. The infrared spectrum of the resin is obtained from a film cast from solution. The stabilizer and filler are examined as Nujol mulls or potassium bromide pellets. Part of the stabilizer and filler is reserved for emission spectrographic analysis. Analytical results on a typical compound are given
Spectrographic Determination of Uranium 235
Authors: Lee Ted , Hallowell A. L. , Rogers Lewis H.
Published: November 2005

This report is the first of a series associated with the development of the spectrographic determination of uranium 235 at the Oak Ridge Gaseous Diffusion Plant The present report, summarizing the development prior to November 1950, deals with the precision obtained using d c arc excitation, photographic recording, and a 21-foot Jarrell-Ash Wadsworth spectrograph in the second order. Measurements were made employing different spectral lines, slit widths, and slit types. For each determination consisting of the average of 10 measurements, a precision of ±0.04 weight per cent uranium 235, expressed at the 95% confidence level, was obtained in the vicinity of naturally occurring uranium (0.7115% uranium 235).
An Electrical Spectrographic Calculator
Authors: Epstein S.
Published: November 2005

An electrical circuit based on analog computer principles has been designed that calculates spectrographic results directly from spectral line transmission values. It operates by solving the equation of the working curve of the element under analysis which must be a straight line in the range that includes all the percentage values of interest. If not straight, the intensity ratio of the analysis and standard lines can be calculated and percentage read from the working curve. Corrections for background and variation in emulsion response with wavelength can also simultaneously be included in the calculation.
The Standard Addition Technique in Flame Spectrometry
Authors: Beukelman T. E. , Lord S. S.
Published: November 2005

The standard addition—logarithmic extrapolation technique has been successfully applied to flame spectrometric analyses. The use of this method makes possible the determination of trace metals in samples without extensive calibration or in standards which have undefined matrices. The mathematical theory of the method has been extended to allow the calculation of the optimum addition sizes and the magnitude of the extrapolation errors. Normally three additions which are equal to, twice, and four times the original amount are optimum. Under these conditions the relative error caused by extrapolation is approximately seven times the relative error in the original intensity measurements. Thus, if the errors in the intensity measurements are ±0.5%, the error in the analysis will be of the order of 4% The utility of the method has been demonstrated in the difficult determination of calcium in the presence of phosphate and the determination of calcium and sodium in a highly viscous organic liquid.
Infrared Spectra of Polynuclear Aromatic Compounds in the C-H Stretching and Out-of-Plane Bending Regions
Authors: Wiberley Stephen E. , Gonzalez Richard D.
Published: November 2005

A study has been made of the infrared spectra of 33 poly-nuclear aromatic compounds including some known carcinogens. In most cases, the number of fused rings may be determined by measuring the frequency of the characteristic aromatic (C-H) stretching vibration with a LiF prism. For unsubstituted fused rings, the (C-H) stretching vibration shifts to lower frequencies as the number of fused rings increases. In addition, the position of the fused rings can be established from data obtained from the out-of-plane (C-H) bending vibrations in the range of 700 to 900 cm−1.
Application of the Tape Technique to the Spectrographic Determination of Mg, Mn, P, and B in Unashed Plant Material
Authors: Zeeman P. B. , Coetzer F. J.
Published: November 2005

A multisource unit and tape machine were employed in the determination of Mg, Mn, P, and B in unashed plant material. The use of working curves from synthetic standards was investigated and found suitable in the case of P. Analysed natural standards were used for obtaining working curves for Mg, Mn, and B. In all cases carbon powder was used as buffer material. The coefficients of variation determined for Mg, Mn, P, and B were 1.44, 4.23, 1 04, and 2 57% respectively.
The Analysis of Uranium Alloys Using a Hollow Cathode
Authors: Goleb Joseph A. , Brody James K.
Published: November 2005

This paper describes investigations that have been made with the Schuller-Gollnow water-cooled hollow-cathode tube for the purpose of using it as an analytical source to analyze fuel materials employed in nuclear reactors. A number of unirradiated normal and enriched uranium alloys have been tested with the above tube using a 21-ft, Wadsworth, Jarrell-Ash grating spectrograph and photographic plates. Results obtained for molybdenum, ruthenium, rhodium, and palladium, in the range of 2 5, 2.0, 0 3, and 0.2% respectively, compare favorably with the point-to-plane technique.
Use of Resolidified Melts in Infrared Spectroscopy: Application to Polymorphism and Solvation Studies
Authors: Grostic Marvin F. , Bronson George E.
Published: November 2005

A sample melt technique has been developed for the rapid identification by infrared spectra of polymorphs and solvates. Excellent spectra are obtained; no decomposition or rearrangements have been detected in studies with 35 compounds, which included 25 steroids Resolidified melt spectra of known polymorphs have been identical. The problems of low solubility and unusable regions of the spectra encountered in solution studies are avoided. In the case of solvates, the solvent may be identified by its spectrum in the gaseous or liquid state, and the spectrum of the solvent-free compound may be determined on the resolidified melt.
Far Ultraviolet Spectroscopy. II. Analytical Applications
Authors: Kaye Wilbur I.
Published: November 2005

One of the prime requirements for the use of a spectral region for analytical purposes is a library of reference spectra. Since no adequate libraries exist, the literature since 1941 has been indexed and references to spectra are listed by empirical formula. The few published analytical applications of far ultraviolet spectroscopy are discussed. With the commercial spectrophotometers that are now available it seems certain that the analysts will make frequent use of this region in the future
Some Characteristics of an Ebert Spectrograph
Authors: Berman S. S. , Tymchuk P. , Russell D. S.
Published: November 2005

Some of the characteristics of an Ebert 34 m plane grating spectrograph have been examined in order to ascertain the optimum conditions for its use in quantitative spectrographic analysis. Of special interest were the higher order; not conveniently reached by many spectrographs produced for general analytical work. A limitation on the use of high dispersions when the dc arc or ac spark is employed as the excitation source is discussed
Far Ultraviolet Spectroscopy. I. Modification of the Beckman DK Spectrophotometer for Automatic Transmittance Recording in the Region 1700–2000 A
Authors: Kaye Wilbur I.
Published: November 2005

Abundant opportunities exist for analytical and molecular structure studies using the far ultraviolet region of the spectrum since almost all compounds in the vapor state possess intense, characteristic, and often detailed absorption spectra. Unfortunately, the experimental difficulties in working in this region have discouraged its widespread use Beckman Model DK-1 and DK-2 spectrophotometers have been modified to perform to 1700 A for the automatic recording of relative transmittance spectra This performance has been accomplished through the use of very high quality quartz and fused silica for prisms and windows. The absorption of the atmosphere in the optical path has been eliminated by purging with nitrogen. The resolution achieved is remarkably good, because of the high dispersion of quartz in this region. Except for the necessity of purging, the experimental difficulties of working to 1700 A are little different from those in near ultraviolet spectroscopy.
The Spectrographic Determination of Molybdenum in Uranium-Molybdenum Alloys
Authors: Purcell Douglas H.
Published: November 2005

Molybdenum can be determined as an alloying constituent in uranium-molybdenum alloys by the point-to-plane spark method of spectrographic analysis. The method covers a concentration range of 1 to 5% molybdenum, and the precision at the 95% confidence level is ± 7%. Time required for the analysis of one sample is about fifteen min.
Minimizing Matrix Effects in Stainless Steel, Type 422, Using Oxygen in the Analytical Gap
Authors: Hullings Robert S.
Published: November 2005

A routine emission spectrographic procedure has been developed for the analysis of stainless steel, Type 422, using the point-to-plane technique. By directing a stream of oxygen onto the face of the sample the accuracy and reproducibility were made better than that obtained in an atmosphere of all.
Infrared Spectra of Vitamins, a Schiff Base, and an Amino Acid Chelate in Water
Authors: Parker Frank S.
Published: November 2005

The infrared spectra of some vitamins in water are presented. The spectra of two forms of vitamin B6 are included and that of the Schiff base formed between pyridoxal phosphate and glycine. The spectrum of copper (L-lysine)2 is given as an example of an amino acid chelate compound in water.