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Effect of vibrational excitation on the dynamics of ion-molecule reactions

Description: A new experimental technique for the study of vibrational effects on ion-molecule reaction cross sections is described. Vibrational and collision energy dependent cross sections are presented for proton and H atom transfer, charge transfer and collision induced dissociation reactions in various isotopic H/sub 2//sup +/ + H/sub 2/ systems. Charge and proton transfer cross sections are presented for the reactions of H/sub 2//sup +/ and D/sub 2//sup +/ with Ar, N/sub 2/, CO, and O/sub 2/. All the reactions are shown to be highly influenced by avoided crossings between the ground and first excited potential energy surfaces. Because of the nature of the crossings, vibrational motion of the systems can cause both adiabatic and non-adiabatic behavior of the system. This makes the vibrational dependences of the various cross sections a very sensitive probe of the dynamics of the collisions particularly, their behavior in the region of the crossings. Evidence is seen for charge transfer between reagents as they approach each other, transition to and in some cases reactions on excited potential energy surfaces, competition between different channels, and strong coupling of proton and charge transfer channels which occurs only for two of the systems studied (H/sub 2//sup +/ + Ar, N/sub 2/). Oscillatory structure is observed in the collision energy dependence of the endoergic H/sub 2//sup +/ (v = 0) + Ar charge transfer reaction for the first time, and a simple model which is commonly used for atom-atom charge transfer is used to fit the peaks. Finally a simple model is used to assess the importance of energy resonance and Franck-Condon effects on molecular charge transfer.
Date: November 1, 1981
Creator: Anderson, S.L.
Partner: UNT Libraries Government Documents Department

Study of the hydrolysis of uranium hexafluoride by Fourier transform infrared spectroscopy

Description: The reaction of uranium hexafluoride with water has been studied by using Fourier transform infrared (FT-IR) spectroscopy. Several different methods for accomplishing this task have been carried out. In addition, interpretatins of the results have been made. These interpretations have been based on literature values for the reactants and for compounds analogous to possible products. It was shown that classical matrix-isolation techniques proved to be unsatisfactory for studying this reaction. Other methods were developed in order to obtain results. They were: (1) the codeposition of pure UF/sub 6/ and H/sub 2/O on a cold window at 16/sup 0/K, (2) the codeposition of argon matrix to sample ratios of 10:1 to 2:1 of UF/sub 6/ and H/sub 2/O at 16/sup 0/K, and (3) the annealing of the samples produced by (1) and (2) while they were being scanned with FT-IR. 78 refs., 86 figs., 7 tabs.
Date: August 1, 1982
Creator: Anderson, S.P.
Partner: UNT Libraries Government Documents Department

Western Gas Sands Project: stratigrapy of the Piceance Basin

Description: The Western Gas Sands Project Core Program was initiated by US DOE to investigate various low permeability, gas bearing sandstones. Research to gain a better geological understanding of these sandstones and improve evaluation and stimulation techniques is being conducted. Tight gas sands are located in several mid-continent and western basins. This report deals with the Piceance Basin in northwestern Colorado. This discussion is an attempt to provide a general overview of the Piceance Basin stratigraphy and to be a useful reference of stratigraphic units and accompanying descriptions.
Date: August 1, 1980
Creator: Anderson, S. (comp.)
Partner: UNT Libraries Government Documents Department

Stability Constants and Intrinsic Solubility of Several Nickel(II)-vic- Dioxime Complexes

Description: An investigation was made to determine the stability constants for several Ni(II) vic-dioximes and to calculate their intrinsic solubility constants. Data and discussion concerning dimethylglyoxime, diethylgiyoxime. di- npropylglyoxime, ethylmethylglyoxime, 4-isoproplynioxime, nioxime, 4- methylnioxime, 3-methylnioxime, heptoxime, and Ni(II) complexes of these vic- dioximes are presented. (J.R.D.)
Date: March 1, 1962
Creator: Banks, C. V. & Anderson, S.
Partner: UNT Libraries Government Documents Department

Western Gas Sands Project: production histories of the Piceance and Uinta basins of Colorado and Utah

Description: Current United States geological tight sand designations in the Piceance and Uinta Basins' Western Gas Sands Project include the Mesaverde Group, Fort Union and Wasatch Formations. Others, such as the Dakota, Cedar Mountain, Morrison and Mancos may eventually be included. Future production from these formations will probably be closely associated with existing trends. Cumulative gas production through December 1979, of the Mesaverde Group, Fort Union and Wasatch Formations in the Piceance and Uinta Basins is less than 275 billion cubic feet. This contrasts dramatically with potential gas in place estimates of 360 trillion cubic feet. If the geology can be fully understood and engineering problems surmounted, significant potential reserves can be exploited.
Date: November 20, 1980
Creator: Anderson, S. & Kohout, J. (comp.)
Partner: UNT Libraries Government Documents Department

VIBRATIONAL ANALYSIS OF UNFIRED HORIZONTAL BAYONET TUBES IN A FLUIDIZED BED CALCINER

Description: The heat exchanger of the calciner consists of a vessel into which unfired, horizontal, bayonet tubes extend in a fluidized bed. Strain measurements were taken on several of the tubes under simulated operating conditions and the associated dynamic stresses were calculated. Vibrations greater than design limitations for indefinite operation were found to exist. To restrict these vibrations and prevent further tube fatigue cracking, a tube support was installed. Since the installation of the support, the calciner has operated satisfactorily over 1275 hours. (auth)
Date: October 19, 1962
Creator: Anderson, S.D. & Hirschi, G.W.
Partner: UNT Libraries Government Documents Department

The effects of chronic radiation on reproductive success of the polychaete worm Neanthes arenaceodentata

Description: The effects of lifetime exposure to chronic irradiation on reproductive success were assessed for laboratory populations of the polychaete worm Neanthes arenaceodentata. Lifetime exposure was initiated upon the spawning of the P1 female and was terminated upon spawning of the F1 female. Groups of experimental worms received either no radiation (controls) or 0.19, 2.1, or 17 mGy/h. The total dose received by the worms was either background or approximately 0.55, 6.5, or 54 Gy, respectively. The broods from the F1 mated pairs were sacrificed before hatching occurred, and information was obtained on brood size, on the number of normal and abnormal embryos, and on the number of embryos that were living, dying, and dead. The mean number of embryos in the broods from the F1 females exposed to lifetime radiation of 0.19 and 2.1 mGy/h was not significantly different from the mean number of embryos from control females; however, the mean number of embryos was different from those F1 females exposed to 17 mGy/h. There was a significant reduction in the number of live embryos in the broods from the F1 mated pairs that were exposed to the lowest dose rate given, 0.19 mGy/h, as well as those exposed to 2.1 and 17 mGy/h. Also, increased percentages of abnormal embryos were determined in the broods of all the radiation-exposed groups. 39 refs., 10 figs., 15 tabs.
Date: December 1, 1988
Creator: Harrison, F.L. & Anderson, S.L.
Partner: UNT Libraries Government Documents Department

Taxonomic and developmental aspects of radiosensitivity

Description: Considerable information is available on the effects of radioactivity on adult and early life stages of organisms. The preponderance of data is on mortality after a single irradiation with relatively high doses. Unfortunately, because experiments were carried out under different conditions and for different time periods, the validity of comparing the results from different laxonomic groups is questionable. In general, the conclusions are that there is a relationship (1) between radioresistance to high doses of acute radiation and taxonomy of the organism, primitive forms being more radioresistant than complex vertebrates and (2) between radiosensitivity and developmental stage, early life stages being more sensitive than later stages. The first conclusion may be related to the capability of the organism to repopulate cells and to differentiate and redifferentiate them; the second to the rate of cellular division and to the degree of differentiation. In question, however, is the relevance of the responses from high levels of acute radiation to that of the responses to long-term exposure to low levels of radiation, which are ecologically of more interest. Data from studies of the effects of acute and chronic exposure on development of gametes and zygotes indicate that, for some fishes and invertebrates, responses at the cellular and molecular levels show effect levels comparable to those observed in some mammals. Acute doses between 0,05 and 0.5Cy and dose rates between 0.02 to 0.2mCy/h appear to define critical ranges in which detrimental effects on fertility are first observed in a variety of radiosensitive organisms. To better understand inherent radiosensitivity, we need more information on the ability of cells to repopulate and differentiate and to prevent or repair damage to biological critical molecules, such as DNA, because these factors may alter significantly organisms` responses to radiation.
Date: November 1, 1996
Creator: Harrison, F.L. & Anderson, S.L.
Partner: UNT Libraries Government Documents Department

Effect of oxidizing environment on mechanical properties of molybdenum and TZM

Description: The effect of environment on mechanical properties of molybdenum and TZM was investigated in low-pressure (1.3-mPa) oxygen at 1150/sup 0/C. Specimens of TZM picked up oxygen and lost carbon. The oxygen concentration increases linearly with exposure time, indicating that the chemisorption of oxygen molecules at the specimen surface, rather than bulk diffusion, controls the kinetics of oxygen absorption at 1150/sup 0/C. Specimens of TZM increase in tensile strength and decrease in ductility with increasing oxygen content. Exposed TZM loses its ductility at elevated temperatures at an oxygen level of 500 ppM. The embrittlement is due to the formation of zones or oxide precipitates, which harden the alloy and promote the brittle fracture associated with cleavage and grain-boundary separation. Unalloyed molybdenum responds to the oxidizing environment quite differently from TZM. The molybdenum (containing no active element such as Ti and Zr) showed no internal oxidation at 1150/sup 0/C. Instead, our results indicate that a trace of oxygen penetrated into molybdenum through its grain boundaries. This penetration raises the ductile-to-brittle transition temperature of molybdenum by 200/sup 0/C lowers the ductility above 900/sup 0/C. The ductility of oxygen-exposed molybdenum is virtually unaffected in the temperature range from 400 to 900/sup 0/C. A ductility minimum (10%) is observed at 1350/sup 0/C because of dynamic embrittlement effects; that is, diffusion of oxygen to grain boundaries or crack tips where high triaxial states of stress are generated during plastic deformation. This embrittlement can be totally eliminated by an increase in strain rate.
Date: October 1, 1978
Creator: Liu, C.T.; Anderson, S.H. & Inouye, H.
Partner: UNT Libraries Government Documents Department

Effects of surface chemistry on the porous structure of coal. Quarterly technical progress report, October 1995--December 1995

Description: The primary objective of this work is to use {sup 129}Xe NMR to characterize the microporous structure of coals. As an aide in this characterization, which is by no means straightforward, another objective is to combine this technique with volumetric adsorption techniques and track the effect of controlled opening of the micropores in a microporous carbon by oxygen chemisorption/desorption. The primary goal of the NMR work is to measure the micropore sizes in coal; more broadly, it is to better tailor the {sup 129}Xe NMR method for use with coal, and to investigate other ways it may be used to describe pore structure in coal, with emphasis on determining whether micropores in coal are connected or isolated. In terms of the primary objectives of the project, the {sup 129}Xe NMR spectra with pressure variation have been obtained for two more coals, completing this task for the sample set of six coals. In terms of the broad objectives of the project, examination of the influence on the xenon signal of packing the powdered coal has been undertaken. These data are of potential value for the determination of whether the porosity is open or closed. Results of powder density and related experiments will be used in the final interpretation of our current data, including the determination of whether, in the NMR of loose powdered, the chemical shift is indicative of the ``true`` gas-solid interaction.
Date: December 31, 1995
Creator: Anderson, S.A.; Radovic, L.R. & Hatcher, P.G.
Partner: UNT Libraries Government Documents Department

First operation of the upgraded SLAC A-Line

Description: The SLAC A-Line has been upgraded to transport electrons to fixed target experiments in End Station A (ESA) with energies up to 50 GeV. From September through November, 1995, this beam line was commissioned and used to deliver 48.36 GeV polarized electrons to Experiment E-154 at 120 pulses/sec and up to 10{sup 11} e{sup {minus}}/pulse. The beam had a full width momentum spread of less than 0.5 percent, and was focused to a small spot ({sigma}=0.7 mm) at the target. In this paper the authors describe the first operational experience with this new beam line.
Date: October 1, 1996
Creator: Erickson, R.; Anderson, S. & Baker, A.
Partner: UNT Libraries Government Documents Department

Effects of surface chemistry on the porous structure of coal. Quarterly technical progress report, October 1996--December 1996

Description: Selective presaturation and saturation transfer {sup 129}Xe NMR experiments were performed on a high volatile C bituminous coal and an anthracite. The experiments detect the movement of xenon atoms among different regions of the internal surface, and to the external surface of the coal particles. The results indicate that adsorbed xenon atoms can move to the external surface of the bituminous coal significantly faster than in the anthracite. The results are interpreted in terms of the porous structure of the coals.
Date: January 1, 1997
Creator: Anderson, S.A.; Hatcher, P.G. & Radovic, L.R.
Partner: UNT Libraries Government Documents Department

Effects of surface chemistry on the porous structure of coal. Quarterly technical progress report, April 1996--June 1996

Description: Objective is to use {sup 129}Xe NMR to study the microporous structure of coals. During this quarter, we have: performed a presaturation experiment on Wyodak subbituminous coal, monitored the progress of Xe adsorption in an anthracite, focusing on the changes observed in the external-surface adsorbed gas signal, used an echo sequence to obtain {sup 129}Xe NMR spectra of Blind Canyon hvAb coal, and improved and repeated the successive oxygen adsorption and desorption experiment on a microporous carbon.
Date: November 1, 1996
Creator: Anderson, S.A.; Radovic, L.R. & Hatcher, P.G.
Partner: UNT Libraries Government Documents Department

Stratigraphy of the unsaturated zone and the Snake River Plain aquifer at and near the Idaho National Engineering Laboratory, Idaho

Description: The unsaturated zone and the Snake River Plain aquifer at and near the Idaho National Engineering Laboratory (INEL) are made up of at least 178 basalt-flow groups, 103 sedimentary interbeds, 6 andesite-flow groups, and 4 rhyolite domes. Stratigraphic units identified in 333 wells in this 890-mile{sup 2} area include 121 basalt-flow groups, 102 sedimentary interbeds, 6 andesite-flow groups, and 1 rhyolite dome. Stratigraphic units were identified and correlated using the data from numerous outcrops and 26 continuous cores and 328 natural-gamma logs available in December 1993. Basalt flows make up about 85% of the volume of deposits underlying the area.
Date: August 1, 1997
Creator: Anderson, S.R. & Liszewski, M.J.
Partner: UNT Libraries Government Documents Department

Effects of surface chemistry on the porous structure of coal. Quarterly technical progress report, July 1996--September 1996

Description: The primary objective of this project is to use {sup 129}Xe NMR to characterize the microporous structure of coals. We will use direct information on pore size, as well as indirect information from adsorption rates and evidence for intra/extraparticle diffusion, to characterize the connectivity of the micropore network. A second objective is to use {sup 129}Xe NMR to describe the effect of controlled opening of the micropores in a microporous carbon by oxygen chemi-sorption/desorption. Our experimental focus in this quarter has been the low power presaturation of the NMR signal of {sup 129}Xe adsorbed in coal. Preliminary work on this experiment was reported in the last quarter. Low power presaturation of {sup 129}Xe adsorbed in two coals produces a hole-burning effect in the adsorbed xenon NMR signals, indicating that these signals are broad due to overlap of a series of chemical shifts. Saturation transfer to the entire adsorbed xenon signal and to the extraparticle gas is observed with increasing presaturation time. Differences in timing of saturation transfer to the external gas have implications for the nature of the connectivity of the pore structures in coal.
Date: October 1, 1996
Creator: Anderson, S.A.; Hatcher, P.G. & Radovic, L.R.
Partner: UNT Libraries Government Documents Department

Effects of surface chemistry on the porous structure of coal. Quarterly technical progress report, January 1996--March 1996

Description: The primary objective of this work is to use {sup 129}Xe NMR to characterize the microporous structure of coals. Another objective is to use this technique to describe the effect of controlled opening of the micropores in a microporous carbon by oxygen chemisorption/desorption. The primary goal of the NMR work is to measure the micropore sizes in coal; more broadly, it is to better tailor the {sup 129}Xe NMR method for use with coal, and to investigate other ways it may be used to describe pore structure in coal, with emphasis on determining whether micropores in coal are connected or isolated. During this quarter, we have: (i) investigated particle size effect on the chemical shift of xenon adsorbed in a set of size-graded vitrinites; (ii) tracked the progress of xenon adsorption via xenon NMR, including particle size effect on the adsorption process; (iii) completed a preliminary test for chemical shift anisotropy in coal; and (iv) examined a microporous carbon by {sup 129}Xe NMR after two cycles of oxygen chemisorption/desorption.
Date: August 1, 1996
Creator: Anderson, S.A.; Radovic, L.R. & Hatcher, P.G.
Partner: UNT Libraries Government Documents Department

Effects of surface chemistry on the porous structure of coal. Technical progress report, September 1994--October 1995

Description: The primary objective of this work is to use {sup 129}Xe NMR to characterize the microporous structure of coals. As an aide in this characterization, another objective is to combine this technique with volumetric adsorption techniques and track the effect of controlled opening of the micropores in a microporous carbon by oxygen chemisorption/desorption. The primary goal of the NMR work is to measure the micropore sizes in coal; more broadly, it is to better tailor the {sup 129}Xe NMR method for use with coal, and to investigate other ways it may be used to describe pore structure in coal, with emphasis on determining whether micropores in coal are connected or isolated. In terms of the primary objectives of the project, the {sup 129}Xe NMR spectra with pressure variation have been completed for four coals, and N{sub 2} and C0{sub 2} adsorption isotherms with surface area measurement have been completed for three coals. A microporous carbon has been subjected to one oxygen chemisorption/desorption cycle and examined by {sup 129}Xe NMR.
Date: December 31, 1995
Creator: Anderson, S.A.; Radovic, L.R. & Hatcher, P.G.
Partner: UNT Libraries Government Documents Department

Evaluation of hydrothermal resources of North Dakota. Phase III final technical report

Description: The hydrothermal resources of North Dakota were evaluated. This evaluation was based on existing data on file with the North Dakota Geological Survey (NDGS) and other state and federal agencies, and field and laboratory studies conducted. The principal sources of data used during the study were WELLFILE, the computer library of oil and gas well data developed during the Phase I study, and WATERCAT, a computer library system of water well data assembled during the Phase II study. A field survey of the shallow geothermal gradients present in selected groundwater observation holes was conducted. Laboratory determinations of the thermal conductivity of core samples were done to facilitate heat-flow calculations on those holes-of-convenience cased.
Date: August 1, 1982
Creator: Harris, K.L.; Howell, F.L.; Wartman, B.L. & Anderson, S.B.
Partner: UNT Libraries Government Documents Department

Evaluation of hydrothermal resources of North Dakota. Phase I, Final technical report

Description: This evaluation is based on an analysis of existing data on file with the North Dakota Geological Survey (NDGS) and other state and federal agencies. The principle source of data used was the oil and gas well files maintained by the NDGS. A computer library was created containing all the necessary oil and gas well data in the North Dakota Geological Survey oil and gas well files. Stratigraphic data, bottomhole-temperature data, and chemical data are presented in map form to show the geothermal gradient, temperature, and depth of potential hydrothermal aquifers and the chemical characteristics of potential hydrothermal aquifers.
Date: April 1, 1980
Creator: Harris, K.L.; Winczewski, L.M.; Umphrey, H.R. & Anderson, S.B.
Partner: UNT Libraries Government Documents Department

Geologic Controls of Hydraulic Conductivity in the Snake River Plain Aquifer At and Near the Idaho National Engineering and Environmental Laboratory, Idaho

Description: The effective hydraulic conductivity of basalt and interbedded sediment that compose the Snake River Plain aquifer at and near the Idaho National Engineering and Environmental Laboratory (INEEL) ranges from about 1.0x10 -2 to 3.2x10 4 feet per day (ft/d). This six-order-of-magnitude range of hydraulic conductivity was estimated from single-well aquifer tests in 114 wells, and is attributed mainly to the physical characteristics and distribution of basalt flows and dikes. Hydraulic conductivity is greatest in thin pahoehoe flows and near-vent volcanic deposits. Hydraulic conductivity is least in flows and deposits cut by dikes. Estimates of hydraulic conductivity at and near the INEEL are similar to those measured in similar volcanic settings in Hawaii. The largest variety of rock types and the greatest range of hydraulic conductivity are in volcanic rift zones, which are characterized by numerous aligned volcanic vents and fissures related to underlying dikes. Three broad categories of hydraulic conductivity corresponding to six general types of geologic controls can be inferred from the distribution of wells and vent corridors. Hydraulic conductivity of basalt flows probably is increased by localized fissures and coarse mixtures of interbedded sediment, scoria, and basalt rubble. Hydraulic conductivity of basalt flows is decreased locally by abundant alteration minerals of probable hydrothermal origin. Hydraulic conductivity varies as much as six orders of magnitude in a single vent corridor and varies from three to five orders of magnitude within distances of 500 to 1,000 feet. Abrupt changes in hydraulic conductivity over short distances suggest the presence of preferential pathways and local barriers that may greatly affect the movement of ground water and the dispersion of radioactive and chemical wastes downgradient from points of waste disposal.
Date: February 1, 1999
Creator: Anderson, S. R.; Kuntz, M. A. & Davis, L. C.
Partner: UNT Libraries Government Documents Department

A program to study CH reactions relevant to combustion/gasification processes

Description: The goal of the proposed work has been to study a small, but important family of CH reactions of interest in combustion-related systems; namely CH + N{sub 2}, H{sub 2}, O{sub 2}, NO, and N{sub 2}O. Until now, these reactions have been studied almost exclusively by IR or UV flash photolysis at moderate temperatures, and little quantitative information about product species has been obtained. The explicit objectives of the present effort were: (1) to develop and characterize a new CW source of CH radicals suitable for use in a fast-flow reactor, (2) to use this source to measure rate constants for several key CH reactions as a function of temperature, and (3) to detect the product channels of these reactions wherever possible. Our accomplishments include: the successful development of a chemical source of CH radicals; the measurement of eight rate constants at 300 K (which agree with previously reported values where available); the detection of OH produced by the CH + NO and O{sub 2} reactions; the completion of a thorough study of isotopic exchange in the products of the reaction CH + CO; and, finally, the taking of the first steps to extending this work to higher temperatures.
Date: January 1, 1989
Creator: Anderson, S.M.; Freedman, A. & Kolb, C.E.
Partner: UNT Libraries Government Documents Department