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Analysis of Copper in the In-Tank Precipitation Process Caustic Samples

Description: Inductively Coupled Plasma Emission Spectroscopy (ICPES) and Inductively Coupled Plasma Mass Spectrometry (ICPMS) procedures for measuring Cu in In-Tank Precipitation (ITP) caustic samples have been tested and implemented in the Analytical Development Section at the Savannah River Technology Center.
Date: December 12, 1996
Creator: Tovo, L.L. & Boyce, W.T.
Partner: UNT Libraries Government Documents Department

Voltametric analysis apparatus and method

Description: An apparatus and method are disclosed for electrochemical analysis of elements in solution. An auxiliary electrode a reference electrode and five working electrodes are positioned in a container containing a sample solution. The working electrodes are spaced apart evenly from each other and auxiliary electrode to minimize any inter-electrode interference that may occur during analysis. An electric potential is applied between auxiliary electrode and each of the working electrodes. Simultaneous measurements taken of the current flow through each of the working electrodes for each given potential in a potential range are used for identifying chemical elements present in sample solution and their respective concentrations. Multiple working electrodes enable a more positive identification to be made by providing unique data characteristic of chemical elements present in the sample solution.
Date: December 1991
Creator: Almon, A. C.
Partner: UNT Libraries Government Documents Department

Field analysis of mercury in water, sediment and soil using static headspace analysis

Description: We developed a field screening method for rapid analysis of Hg in water, soil, and sediment, which can be applied cost-effectively at Hg-contaminated sites. Samples are chemically pretreated in ordinary containers, followed by analysis of the sample headspace Hg vapor using a portable commercial analyzer. Hg in water samples is reduced directly by the addition of stannous chloride, while solids are first digested with aqua regia or piranha solution to liberate the Hg from the solids. Aided by vigorous agitation after adding the reductant, the elemental Hg partitions between solution and headspace according to Henry`s Law. The method requires about 2 and 15 minutes to complete for water and solids, respectively. The method provides very useful detection limits for water (0.1 {mu}g/L) and solids (2-3{mu}g/g). Intercomparisons with laboratory-analyzed environmental samples show good agreement.
Date: December 31, 1994
Creator: Kriger, A.A. & Turner, R.R.
Partner: UNT Libraries Government Documents Department

Procedure for plutonium determination using Pu(VI) spectra

Description: This document describes a simple spectrophotometric method for determining total plutonium in nitric acid solutions based on the spectrum of Pu(VI). Plutonium samples in nitric acid are oxidized to Pu(VI) with Ce(IV) and the net absorbance at the 830 nm peak is measured.
Date: September 1, 1996
Creator: Walker, L.F.; Temer, D.J. & Jackson, D.D.
Partner: UNT Libraries Government Documents Department

Thin-film device for process measurement. Final report

Description: The development of a compact, portable planar waveguide spectrometer has been developed and successfully applied to a variety of chemical and petrochemical analytical problems. The technology is well suited to liquid samples that are difficult to analyze by conventional means.
Date: February 1, 1996
Creator: Goldman, D.S.
Partner: UNT Libraries Government Documents Department

Background concentrations of metals in wetland soils on and near the Savannah River site

Description: A study was conducted to determine the naturally occurring concentrations of metals in unimpacted wetland soils at the Savannah River Site located near Aiken, SC. Soil samples were collected from three broad categories of wetlands: (1) large stream floodplain wetlands, (2) small stream floodplain wetlands, and (3) upland bays and depressions. Samples were collected from 75 locations to a depth of 3.1 m. All samples were analyzed for selected metals using EPA protocol and standard methods. Additionally, the pH, exchange capacity, and total organic carbon content of each sample was determined. Standard summary statistics were calculated and results are presented for each constituent. Box plots were also created relating metals concentrations to grain size distribution. Metals concentrations were found to increase with increasing silt and clay content. This increase in concentration was attributed to increasing cation exchange capacity and increasing organic matter content.
Date: September 1, 1997
Creator: Dixon, K.L.
Partner: UNT Libraries Government Documents Department

ICPES analyses using full image spectra and astronomical data fitting algorithms to provide diagnostic and result information

Description: ICP emission analyses are prone to errors due to changes in power level, nebulization rate, plasma temperature, and sample matrix. As a result, accurate analyses of complex samples often require frequent bracketing with matrix matched standards. Information needed to track and correct the matrix errors is contained in the emission spectrum. But most commercial software packages use only the analyte line emission to determine concentrations. Changes in plasma temperature and the nebulization rate are reflected by changes in the hydrogen line widths, the oxygen emission, and neutral ion line ratios. Argon and off-line emissions provide a measure to correct the power level and the background scattering occurring in the polychromator. The authors` studies indicated that changes in the intensity of the Ar 404.4 nm line readily flag most matrix and plasma condition modifications. Carbon lines can be used to monitor the impact of organics on the analyses and calcium and argon lines can be used to correct for spectral drift and alignment. Spectra of contaminated groundwater and simulated defense waste glasses were obtained using a Thermo Jarrell Ash ICP that has an echelle CID detector system covering the 190-850 nm range. The echelle images were translated to the FITS data format, which astronomers recommend for data storage. Data reduction packages such as those in the ESO-MIDAS/ECHELLE and DAOPHOT programs were tried with limited success. The radial point spread function was evaluated as a possible improved peak intensity measurement instead of the common pixel averaging approach used in the commercial ICP software. Several algorithms were evaluated to align and automatically scale the background and reference spectra. A new data reduction approach that utilizes standard reference images, successive subtractions, and residual analyses has been evaluated to correct for matrix effects.
Date: October 1, 1997
Creator: Spencer, W.A. & Goode, S.R.
Partner: UNT Libraries Government Documents Department

Review of analytical results from the proposed agent disposal facility site, Aberdeen Proving Ground

Description: Argonne National Laboratory reviewed the analytical results from 57 composite soil samples collected in the Bush River area of Aberdeen Proving Ground, Maryland. A suite of 16 analytical tests involving 11 different SW-846 methods was used to detect a wide range of organic and inorganic contaminants. One method (BTEX) was considered redundant, and two {open_quotes}single-number{close_quotes} methods (TPH and TOX) were found to lack the required specificity to yield unambiguous results, especially in a preliminary investigation. Volatile analytes detected at the site include 1, 1,2,2-tetrachloroethane, trichloroethylene, and tetrachloroethylene, all of which probably represent residual site contamination from past activities. Other volatile analytes detected include toluene, tridecane, methylene chloride, and trichlorofluoromethane. These compounds are probably not associated with site contamination but likely represent cross-contamination or, in the case of tridecane, a naturally occurring material. Semivolatile analytes detected include three different phthalates and low part-per-billion amounts of the pesticide DDT and its degradation product DDE. The pesticide could represent residual site contamination from past activities, and the phthalates are likely due, in part, to cross-contamination during sample handling. A number of high-molecular-weight hydrocarbons and hydrocarbon derivatives were detected and were probably naturally occurring compounds. 4 refs., 1 fig., 8 tabs.
Date: September 1, 1997
Creator: Brubaker, K.L.; Reed, L.L.; Myers, S.W.; Shepard, L.T. & Sydelko, T.G.
Partner: UNT Libraries Government Documents Department

Inductively coupled plasma mass spectrometry with a twin quadrupole instrument using laser ablation sample introduction and monodisperse dried microparticulate injection

Description: The focus of this dissertation is the use of a twin quadrupole inductively coupled plasma mass spectrometer (ICP-MS) for the simultaneous detection of two m/z values. The twin quadrupole ICP-MS is used with laser ablation sample introduction in both the steady state (10 Hz) and single pulse modes. Steady state signals are highly correlated and the majority of flicker noise cancels when the ratio is calculated. Using a copper sample, the isotope ratio {sup 63}Cu{sup +}/{sup 65}Cu{sup +} is measured with a relative standard deviation (RSD) of 0.26%. Transient signals for single laser pulses are also obtained. Copper isotope ratio measurements for several laser pulses are measured with an RSD of 0.85%. Laser ablation (LA) is used with steel samples to assess the ability of the twin quadrupole ICP-MS to eliminate flicker noise of minor components of steel samples. Isotopic and internal standard ratios are measured in the first part of this work. The isotope ratio {sup 52}Cr{sup +}/{sup 53}Cr{sup +} (Cr present at 1.31 %) can be measured with an RSD of 0.06 % to 0.1 %. For internal standard elements, RSDs improve from 1.9 % in the Cr{sup +} signal to 0.12% for the ratio of {sup 51}V{sup +} to {sup 52}Cr{sup +}. In the second part of this work, one mass spectrometer is scanned while the second channel measures an individual m/z value. When the ratio of these two signals is calculated, the peak shapes in the mass spectrum are improved significantly. Pulses of analyte and matrix ions from individual drops are measured simultaneously using the twin quadrupole ICP-MS with monodisperse dried microparticulate injection (MDMI). At modest Pb concentrations (500 ppm), a shoulder on the leading edge of the Li{sup +} signal becomes apparent. Space charge effects are consistent with the disturbances seen.
Date: February 1, 1997
Creator: Allen, L.A.
Partner: UNT Libraries Government Documents Department

Determination of halogens in a petroleum product by ion chromatography

Description: A rapid, high-performance ion chromatography (HPIC) method with isocratic separation and the anion self-regenerating suppressor (in the chemical suppression mode, specifically for the determination of fluoride, chloride, bromide, and iodide in a petroleum product) is discussed. This is a proposed new method for a production laboratory within the Analytical Services Organization at the Oak Ridge Y-12 Plant.
Date: July 15, 1994
Creator: Tucker, H.L.
Partner: UNT Libraries Government Documents Department

Coulometric Titration of Microgram Amounts of Americium at the Conducting Glass Electrode

Description: Coulograms of Am(III) in carbonate electrolyte exhibit a well-defined wave for the Am(III)-Am(V) oxidation step at the conduction glass electrode. This wave provides the basis of a method for the quantitative titration of this element at the 30-microgram level with a precision of 1.5 percent. The method is restricted to pure solutions; corrections are required for the partial oxidation of Am(V) to Am(VI) and the reduction of Am(VI) by water.
Date: August 29, 2001
Creator: Propst, R.C.
Partner: UNT Libraries Government Documents Department

Evaluation on the use of cerium in the NBL Titrimetric Method

Description: An alternative to potassium dichromate as titrant in the New Brunswick Laboratory Titrimetric Method for uranium analysis was sought since chromium in the waste makes disposal difficult. Substitution of a ceric-based titrant was statistically evaluated. Analysis of the data indicated statistically equivalent precisions for the two methods, but a significant overall bias of +0.035% for the ceric titrant procedure. The cause of the bias was investigated, alterations to the procedure were made, and a second statistical study was performed. This second study revealed no statistically significant bias, nor any analyst-to-analyst variation in the ceric titration procedure. A statistically significant day-to-day variation was detected, but this was physically small (0.01 5%) and was only detected because of the within-day precision of the method. The added mean and standard deviation of the %RD for a single measurement was found to be 0.031%. A comparison with quality control blind dichromate titration data again indicated similar overall precision. Effects of ten elements on the ceric titration`s performance was determined. Co, Ti, Cu, Ni, Na, Mg, Gd, Zn, Cd, and Cr in previous work at NBL these impurities did not interfere with the potassium dichromate titrant. This study indicated similar results for the ceric titrant, with the exception of Ti. All the elements (excluding Ti and Cr), caused no statistically significant bias in uranium measurements at levels of 10 mg impurity per 20-40 mg uranium. The presence of Ti was found to cause a bias of {minus}0.05%; this is attributed to the presence of sulfate ions, resulting in precipitation of titanium sulfate and occlusion of uranium. A negative bias of 0.012% was also statistically observed in the samples containing chromium impurities.
Date: March 1, 1995
Creator: Zebrowski, J.P.; Orlowicz, G.J.; Johnson, K.D.; Smith, M.M. & Soriano, M.D.
Partner: UNT Libraries Government Documents Department

Selective spectroscopic methods for water analysis

Description: This dissertation explores in large part the development of a few types of spectroscopic methods in the analysis of water. Methods for the determination of some of the most important properties of water like pH, metal ion content, and chemical oxygen demand are investigated in detail. This report contains a general introduction to the subject and the conclusions. Four chapters and an appendix have been processed separately. They are: chromogenic and fluorogenic crown ether compounds for the selective extraction and determination of Hg(II); selective determination of cadmium in water using a chromogenic crown ether in a mixed micellar solution; reduction of chloride interference in chemical oxygen demand determination without using mercury salts; structural orientation patterns for a series of anthraquinone sulfonates adsorbed at an aminophenol thiolate monolayer chemisorbed at gold; and the role of chemically modified surfaces in the construction of miniaturized analytical instrumentation.
Date: June 24, 1997
Creator: Vaidya, B.
Partner: UNT Libraries Government Documents Department

Rapid analysis of hay attributes using NIRS. Final report, Task II alfalfa supply system

Description: This final report provides technical information on the development of a near infrared reflectance spectroscopy (NIRS) system for the analysis of alfalfa hay. The purpose of the system is to provide consistent quality for processing alfalfa stems for fuel and alfalfa leaf meal products for livestock feed. Project tasks were to: (1) develop an NIRS driven analytical system for analysis of alfalfa hay and processed alfalfa products; (2) assist in hiring a qualified NIRS technician and recommend changes in testing equipment necessary to provide accurate analysis; (3) calibrate the NIRS instrument for accurate analyses; and (4) develop prototype equipment and sampling procedures as a first step towards development of a totally automated sampling system that would rapidly sample and record incoming feedstock and outbound product. An accurate hay testing program was developed, along with calibration equations for analyzing alfalfa hay and sun-cured alfalfa pellets. A preliminary leaf steam calibration protocol was also developed. 7 refs., 11 figs., 10 tabs.
Date: October 24, 1997
Partner: UNT Libraries Government Documents Department

Development and evaluation of high resolution quadrupole mass analyzer and an inductively coupled plasma-Mach disk

Description: By definition a plasma is an electrically conducting gaseous mixture containing a significant concentration of cations and electrons. The Inductively Coupled Plasma (ICP) is an electrodeless discharge in a gas at atmospheric pressure. This discharge is an excellent one for vaporizing, atomizing, and ionizing elements. The early development of the ICP began in 1942 by Babat and then by Reed in the early 1960s. This was then followed by the pioneering work of Fassel and coworkers in the late 1960s. Commercial ICP spectrometers were introduced in the mid 1970s. A major breakthrough in the area of ICP took place in the early 1980s when the ICP was shown to be an excellent ion source for mass spectrometry.
Date: December 10, 1999
Creator: Amad, Ma'an Hazem
Partner: UNT Libraries Government Documents Department

Waste minimization methods for treating analyticl instrumentation effluents at the source

Description: Recently there has been increasing interest in minimizing analytical laboratory wastes. The driving forces behind this interest are the ever increasing costs and liabilities associated with waste disposal. Thus, many analytical laboratories, like the Defense Waste Processing Technology-Analytical Laboratory (DWPT-AL), located at the Savannah River Site (SRS), are looking into treating their own wastes. The DWPT-AL operates four laboratory modules that produce hazardous liquid effluents from the analytical instrumentation: Spectroscopy, Chromatography I, Chromatography II, and Wet Chemistry. The hazardous waste from these modules is being sent to SRS Waste Management at a cost of approximately $13,000 per drum, which corresponds to approximately $325,000 to $520,000 per year. If the hazardous characteristics of and the hazardous components in the analytical instrument effluents or example preparation wastes can be altered and/or reduced in such a way as to render the stream non-hazardous, the large volume of non-hazardous waste can be disposed of via process drains. Therefore, the primary goal of this project was to reduce the amount of hazardous waste being generated by the DWPT-AL, thereby substantially reducing the costs associated with its disposal. A secondary goal was to develop in-line methods using primarily adsorption/ion exchange columns that can be used to treat the liquid effluent as it emerges from the analytical instrument as a slow, dripping flow. The second goal allows the treatment method to become part of the operating procedure associated with the instrument; thus, the effluent would not be considered a waste until it emerges from the in-line column.
Date: December 1, 1995
Creator: Policke, T.R.; Ritter, J.A. & Barnhart, C.
Partner: UNT Libraries Government Documents Department

Laser desorption mass spectrometry for fast DNA analysis

Description: During the past few years, major effort has been directed toward developing mass spectrometry to measure biopolymers because of the great potential benefit to biomedical research. Hellenkamp and his co-workers were the first to report that large polypeptide molecules can be ionized and detected without significant fragmentation when a greater number of nicotinic acid molecules are used as a matrix. This method is now well known as matrix-assisted laser desorption/ionization (MALDI). Since then, various groups have reported measurements of very large proteins by MALDI. Reliable protein analysis by MALDI is more or less well established. However, the application of MALDI to nucleic acids analysis has been found to be much more difficult. Most research on the measurement of nucleic acid by MALDI were stimulated by the Human Genome Project. Up to now, the only method for reliable routine analysis of nucleic acid is gel electrophoresis. Different sizes of nucleic acids can be separated in gel medium when a high electric field is applied to the gel. However, the time needed to separate different sizes of DNA segments usually takes from several minutes to several hours. If MALDI can be successfully used for nucleic acids analysis, the analysis time can be reduced to less than I millisecond. In addition, no tagging with radioactive materials or chemical dyes is needed. In this work, we will review recent progress related to MALDI for DNA analysis.
Date: September 1995
Creator: Chen, C.H.; Ch`ang, L.Y.; Taranenko, N.I.; Allman, S.L.; Tang, K. & Matteson, K.J.
Partner: UNT Libraries Government Documents Department

A device for the determination of low concentrations of oxygen in carbonaceous materials

Description: Oxygen in carbonaceous materials is converted to carbon monoxide (CO) by pyrolyzing the material in a stream of oxygen-free helium. The CO is reacted with Ni{sup 63}, a radioactive isotope of nickel, to form nickel tetracarbanyl (Ni{sup 63}(CO){sub 4}) which is carried by the helium stream into a flow-through gas proportional counter. The quantity of Ni(CO){sub 4} is determined by the radioactivity of the gas as measured by the gas proportional counter. After exiting the flow through counter the Ni{sub 63}(CO){sub 4} is destroyed by exposing it to high temperatures. The Ni{sub 63} is retained within the apparatus while the CO is flushed from the system after being oxidized to carbon dioxide (CO{sub 2}). The detection limit is estimated to be less than 1 part per billion oxygen for a 10 mg sample.
Date: December 31, 1991
Creator: Schultz, H.
Partner: UNT Libraries Government Documents Department

Chlorophyll fluorescence analysis and imaging in plant stress and disease

Description: Quantitative analysis of chlorophyll fluorescence transients and quenching has evolved rapidly in the last decade. Instrumentation capable of fluorescence detection in bright actinic light has been used in conjunction with gas exchange analysis to build an empirical foundation relating quenching parameters to photosynthetic electron transport, the state of the photoapparatus, and carbon fixation. We have developed several instruments that collect video images of chlorophyll fluorescence. Digitized versions of these images can be manipulated as numerical data arrays, supporting generation of quenching maps that represent the spatial distribution of photosynthetic activity in leaves. We have applied this technology to analysis of fluorescence quenching during application of stress hormones, herbicides, physical stresses including drought and sudden changes in humidity of the atmosphere surrounding leaves, and during stomatal oscillations in high CO{sub 2}. We describe a recently completed portable fluorescence imaging system utilizing LED illumination and a consumer-grade camcorder, that will be used in long-term, non-destructive field studies of plant virus infections.
Date: December 1, 1994
Creator: Daley, P. F.
Partner: UNT Libraries Government Documents Department