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Quantum Monte Carlo study of the reaction: C1 + CH3OH -->CH2OH+ HCl

Description: A theoretical study is reported of the Cl + CH{sub 3}OH {yields} CH{sub 2}OH + HCl reaction based on the diffusion Monte Carlo (DMC) variant of the quantum Monte Carlo method. Using a DMC trial function constructed as a product of Hartree-Fock and correlation functions, we have computed the barrier height, heat of reaction, atomization energies and heats of formation of reagents and products. The DMC heat of reaction, atomization energies, and heats of formation are found to agree with experiment to within the error bounds of computation and experiment. Moller-Plesset second order perturbation theory (MP2) and density functional theory, the latter in the B3LYP generalized gradient approximation, are found to overestimate the experimental heat of reaction. Intrinsic reaction coordinate calculations at the MP2 level of theory demonstrate that the reaction is predominantly direct, i.e., proceeds without formation of intermediates, which is consistent with a recent molecular beam experiment. The reaction barrier as determined from MP2 calculations is found to be 2.24 kcal/mol and by DMC it is computed to be 2.39(49) kcal/mol.
Date: December 1, 2003
Creator: Kollias, A.C.; Couronne, O. & Lester Jr., W.A.
Partner: UNT Libraries Government Documents Department

Systematic changes of the Nb-Sn reaction with time, temperature and alloying in Restacked-Rod-Process (RRP) Nb3Sn strands

Description: Reaction heat treatments spanning 605 to 750 C and 24 to {approx}400 hours were applied to several sets of RRP strands. Magnetization and transport measurements were used to track the changes of superconducting properties and the amounts of Nb{sub 3}Sn formed. The experiments showed that temperature increases of 15 C produced equivalent properties in half the time within the temperature range 620-680 C. This result was the same whether Ta or Ti was used to alloy the Nb{sub 3}Sn. The bulk pinning force Fp for Ta-alloyed wires displayed a significant drop for temperatures outside the range above, due to tin gradients at low temperatures and grain growth at high temperatures. The F{sub p} drop at high reaction temperatures prevents wire technology from taking advantage of significantly higher Kramer-plot intercept H{sub K} for high-temperature reactions. On the other hand, Ti alloying provides a quick and potent means to increase H{sub K} at reaction temperatures for which F{sub p} remains high.
Date: September 1, 2008
Creator: Ghosh, A.K.; Sperry, E.A.; D'Ambra, J.; /Brookhaven; Cooley, L.D. & /Fermilab
Partner: UNT Libraries Government Documents Department

Thermal response of a can handling unit (CHU) to a postulated plutonium hydride burn

Description: A series of analyses were performed to support the design of the Can Handling Unit (CHU). The subject analyses focused on determining the time to repressurize a subatmospheric storage can containing plutonium metal versus the initial hole size and the transient thermal response to a postulated chemical reaction of 150 grams of plutonium hydride. Limiting the amount of gaseous reactants either by inerting the CHU or using a very small hole size for the initial opening appears to be a viable method of controlling the rate of the exothermic chemical reactions and system temperatures.
Date: May 21, 1998
Creator: Crea, B. A.
Partner: UNT Libraries Government Documents Department

Thermal analysis of thermo-gravimetric measurements of spent nuclear fuel oxidation rates

Description: A detailed thermal analysis was completed of the sample temperatures in the Thermo-Gravimetric Analysis (TGA) system used to measure irradiated N Reactor fuel oxidation rates. Sample temperatures during the oxidation process did not show the increase which was postulated as a result of the exothermic reactions. The analysis shows the axial conduction of heat in the sample holder effectively removes the added heat and only a very small, i.e., <10 C, increase in temperature is calculated. A room temperature evaporation test with water showed the sample thermocouple sensitivity to be more than adequate to account for a temperature change of approximately 5 C. Therefore, measured temperatures in the TGA are within approximately 10 C of the actual sample temperatures and no adjustments to reported data to account for the heat input from the oxidation process are necessary.
Date: October 9, 1997
Creator: Cramer, E.R.
Partner: UNT Libraries Government Documents Department

[Energies of organic compounds]

Description: The first part of our study of the enthalpy of reduction of carbonyl compounds has been completed and includes four aldehydes, acetone, a series of cyclic ketones and ethyl acetate. Results suggest that some of the literature data for these compounds are significantly in error. Equilibrium constants have been measured for the reaction of carbonyl compounds with water to give hydrates as well as with methanol to give either hemiacetals or acetals. They cover a wide range, and studies are underway to determine the reasons for the differences. Studies of the enthalpies of hydration of some alkenes which yield tertiary alcohols have been completed, as well as a study of the hydrolysis of lactones. The ``gauche effect`` has been studied, and has been shown to result from the formation of bent bonds when atoms of much different electronegativity are joined.
Date: July 1, 1995
Partner: UNT Libraries Government Documents Department

A unique method of neutron flux determination from experimental data

Description: A method is provided for determining the fission heat flux of a prime specimen inserted into a specimen of a test reactor. A pair of thermocouple test specimens are positioned at the same level in the holder and a determination is made of various experimental data including the temperature of the thermocouple test specimens, the temperature of bulk water channels located in the test holder, the gamma scan count ratios for the thermocouple test specimens and the prime specimen, and the thicknesses of the outer clads, the fuel fillers, and the backclad of the thermocouple test specimen. Using this experimental data, the absolute value of the fission heat flux for the thermocouple test specimens and prime specimen can be calculated.
Date: December 1, 1998
Creator: Paxton, Frank A.
Partner: UNT Libraries Government Documents Department

Energies of organic compounds. Technical progress report

Description: A procedure was developed for carbonyl group reduction using triethylborohydride. Esters and lactones are readily reduced and are suitable as substrates. Some enthalpies of hydrolysis of lactones and esters were measured. Heats of trifluoroacetolysis of alkenes leading to tertiary alcohols were measured; some cyclic systems were also investigated. In order to study the effect of {alpha}-alkyl substituents on ketones, rotational barriers adjacent to carbonyl groups were studied.
Date: August 12, 1987
Creator: Wiberg, K.B.
Partner: UNT Libraries Government Documents Department

A first-principles density functional theory study of the electronic structural and thermodynamic properties of M2ZrO3 and M2CO3 (M=Na, K) and their capabilities for CO2 capture

Description: Alkali metal zirconates could be used as solid sorbents for CO{sub 2} capture. The structural, electronic, and phonon properties of Na{sub 2}ZrO{sub 3}, K{sub 2}ZrO{sub 3}, Na{sub 2}CO{sub 3}, and K{sub 2}CO{sub 3} are investigated by combining the density functional theory with lattice phonon dynamics. The thermodynamics of CO{sub 2} absorption/desorption reactions of these two zirconates are analyzed. The calculated results show that their optimized structures are in a good agreement with experimental measurements. The calculated band gaps are 4.339 eV (indirect), 3.641 eV (direct), 3.935 eV (indirect), and 3.697 eV (direct) for Na{sub 2}ZrO{sub 3}, K{sub 2}ZrO{sub 3}, Na{sub 2}CO{sub 3}, and K{sub 2}CO{sub 3}, respectively.The calculated phonon dispersions and phonon density of states for M{sub 2}ZrO{sub 3} and M{sub 2}CO{sub 3} (M = K, Na, Li) revealed that from K to Na to Li, their frequency peaks are shifted to high frequencies due to the molecular weight decreased from K to Li. From the calculated reaction heats and relationships of free energy change versus temperatures and CO{sub 2} pressures of the M{sub 2}ZrO{sub 3} (M = K, Na, Li) reacting with CO{sub 2}, we found that the performance of Na{sub 2}ZrO{sub 3} capturing CO{sub 2} is similar to that of Li{sub 2}ZrO{sub 3} and is better than that of K{sub 2}ZrO{sub 3}. Therefore, Na{sub 2}ZrO{sub 3} and Li{sub 2}ZrO{sub 3} are good candidates of high temperature CO{sub 2} sorbents and could be used for post combustion CO{sub 2} capture technologies.
Date: January 1, 2012
Creator: Duan, Yuhua
Partner: UNT Libraries Government Documents Department

THE HYDROLYSIS AND OXIDATION BEHAVIOR OF LITHIUM BOROHYDRIDE AND MAGNESIUM HYDRIDE DETERMINED BY CALORIMETRY

Description: Lithium borohydride, magnesium hydride and the 2:1 'destabilized' ball milled mixtures (2LiBH{sub 4}:MgH{sub 2}) underwent liquid phase hydrolysis, gas phase hydrolysis and air oxidation reactions monitored by isothermal calorimetry. The experimentally determined heats of reaction and resulting products were compared with those theoretically predicted using thermodynamic databases. Results showed a discrepancy between the predicted and observed hydrolysis and oxidation products due to both kinetic limitations and to the significant amorphous character of observed reaction products. Gas phase and liquid phase hydrolysis were the dominant reactions in 2LiBH{sub 4}:MgH{sub 2} with approximately the same total energy release and reaction products; liquid phase hydrolysis displayed the maximum heat flow for likely environmental exposure with a peak energy release of 6 (mW/mg).
Date: March 13, 2008
Creator: Brinkman, K; Donald Anton, D; Joshua Gray, J & Bruce Hardy, B
Partner: UNT Libraries Government Documents Department

Thermal analyses of the TiH{sub x}/KClO{sub 4} system

Description: Typical pyrotechnic reaction exotherms are shown for a number of pyrotechnic blends prepared from Ti hydrides of several hydride compositions. Rate appears to increase with increasing hydrogen in the Ti hydride.
Date: December 31, 1976
Creator: Reed, J.W.; Ivey, J.L.; Fread, C.L.; Steinmeyer, R.H.; Yauger, R.L. & Abell, G.C.
Partner: UNT Libraries Government Documents Department

Simple relationships for estimating intraparticle transport effects for catalytically promoted endothermic reactions

Description: Relationships for estimating effectiveness factors for porous-solid-catalyzed fluid reactions can result from assuming approximations to temperature and concentration profiles. Approximations designed to simplify the outcome result in simple, explicit, analytic relationships for both isothermal and nonisothermal nth-order reaction systems. For isothermal systems, formulas developed predict effectiveness within 25% of the true isothermal effectiveness factors ({eta}`s) over the range 0.1 > {eta} > 0.99. For isothermal or endothermic reaction systems with {eta} > 0.65, errors are less than 10%. Even in the maximum-error region, estimates for endothermic systems are within a factor of two of those obtained by solution of the rigorous heat and mass transfer equations. For isothermal or endothermic systems with {eta} > 0.95, errors are less than 1%. Thus the formulas can also serve diagnostic uses that confirm presence or absence of significant internal heat or mass transport effects in porous reacting systems. Extension of the approach to non-nth-order reactions is possible; formulas are derived for simple isothermal and nonisothermal Langmuir-Hinshelwood reaction systems. Application of the work to exothermic reactions was not tested, but steeper gradients in such systems would tend to degrade accuracy of the relationships. The equations derived in this work are simpler and easier of application than any others proposed thus far.
Date: June 16, 1998
Creator: Brown, L. F.
Partner: UNT Libraries Government Documents Department

Theoretical energy release of thermites, intermetallics, and combustible metals

Description: Thermite (metal oxide) mixtures, intermetallic reactants, and metal fuels have long been used in pyrotechnic applications. Advantages of these systems typically include high energy density, impact insensitivity, high combustion temperature, and a wide range of gas production. They generally exhibit high temperature stability, and possess insensitive ignition properties. In this paper, the authors review the applications, benefits, and characteristics of thermite mixtures, intermetallic reactants, and metal fuels. Calculated values for reactant density, heat of reaction (per unit mass and per unit volume), and reaction temperature (without and with consideration of phase changes and the variation of specific heat values) are tabulated. These data are ranked in several ways, according to density, heat of reaction, reaction temperature, and gas production.
Date: June 1, 1998
Creator: Fischer, S.H. & Grubelich, M.C.
Partner: UNT Libraries Government Documents Department

Energies of organic compounds. Final report

Description: The objective of this research was to gain information on the energies of organic compounds and on the factors that control energies. The work involved calorimetric measurements of energy changes and theoretical studies of intramolecular interactions and molecular energies.
Date: July 1, 1995
Partner: UNT Libraries Government Documents Department

HEAT OF HYDRATION OF SALTSTONE MIXES-MEASUREMENT BY ISOTHERMAL CALORIMETRY

Description: This report provides initial results on the measurement of heat of hydration of Saltstone mixes using isothermal calorimetry. The results were obtained using a recently purchased TAM Air Model 3116 Isothermal Conduction Calorimeter. Heat of hydration is an important property of Saltstone mixes. Greater amounts of heat will increase the temperature of the curing mix in the vaults and limit the processing rate. The heat of hydration also reflects the extent of the hydraulic reactions that turn the fluid mixture into a ''stone like'' solid and consequently impacts performance properties such as permeability. Determining which factors control these reactions, as monitored by the heat of hydration, is an important goal of the variability study. Experiments with mixes of portland cement in water demonstrated that the heats measured by this technique over a seven day period match very well with the literature values of (1) seven day heats of hydration using the standard test method for heat of hydration of hydraulic cement, ASTM C 186-05 and (2) heats of hydration measured using isothermal calorimetry. The heats of hydration of portland cement or blast furnace slag in a Modular Caustic Side Solvent Extraction Unit (MCU) simulant revealed that if the cure temperature is maintained at 25 C, the amount of heat released over a seven day period is roughly 62% less than the heat released by portland cement in water. Furthermore, both the blast furnace slag and the portland cement were found to be equivalent in heat production over the seven day period in MCU. This equivalency is due to the activation of the slag by the greater than 1 Molar free hydroxide ion concentration in the simulant. Results using premix (a blend of 10% cement, 45% blast furnace slag, and 45% fly ash) in MCU, Deliquification, Dissolution and Adjustment (DDA) and ...
Date: July 2, 2007
Creator: Harbour, J; Vickie Williams, V & Tommy Edwards, T
Partner: UNT Libraries Government Documents Department

INTEGRATED HYDROGEN STORAGE SYSTEM MODEL

Description: Hydrogen storage is recognized as a key technical hurdle that must be overcome for the realization of hydrogen powered vehicles. Metal hydrides and their doped variants have shown great promise as a storage material and significant advances have been made with this technology. In any practical storage system the rate of H2 uptake will be governed by all processes that affect the rate of mass transport through the bed and into the particles. These coupled processes include heat and mass transfer as well as chemical kinetics and equilibrium. However, with few exceptions, studies of metal hydrides have focused primarily on fundamental properties associated with hydrogen storage capacity and kinetics. A full understanding of the complex interplay of physical processes that occur during the charging and discharging of a practical storage system requires models that integrate the salient phenomena. For example, in the case of sodium alanate, the size of NaAlH4 crystals is on the order of 300nm and the size of polycrystalline particles may be approximately 10 times larger ({approx}3,000nm). For the bed volume to be as small as possible, it is necessary to densely pack the hydride particles. Even so, in packed beds composed of NaAlH{sub 4} particles alone, it has been observed that the void fraction is still approximately 50-60%. Because of the large void fraction and particle to particle thermal contact resistance, the thermal conductivity of the hydride is very low, on the order of 0.2 W/m-{sup o}C, Gross, Majzoub, Thomas and Sandrock [2002]. The chemical reaction for hydrogen loading is exothermic. Based on the data in Gross [2003], on the order of 10{sup 8}J of heat of is released for the uptake of 5 kg of H{sub 2}2 and complete conversion of NaH to NaAlH{sub 4}. Since the hydride reaction transitions from hydrogen loading to discharge ...
Date: November 16, 2007
Creator: Hardy, B
Partner: UNT Libraries Government Documents Department

Thermodynamic States in Explosion Fields

Description: Here we investigate the thermodynamic states occurring in explosion fields from the detonation of condensed explosives in air. In typical applications, the pressure of expanded detonation products gases is modeled by a Jones-Wilkins-Lee (JWL) function: P{sub JWL} = f(v,s{sub CJ}); constants in that function are fit to cylinder test data. This function provides a specification of pressure as a function of specific volume, v, along the expansion isentrope (s = constant = s{sub CJ}) starting at the Chapman-Jouguet (CJ) state. However, the JWL function is not a fundamental equation of thermodynamics, and therefore gives an incomplete specification of states. For example, explosions inherently involve shock reflections from surfaces; this changes the entropy of the products, and in such situations the JWL function provides no information on the products states. In addition, most explosives are not oxygen balanced, so if hot detonation products mix with air, they after-burn, releasing the heat of reaction via a turbulent combustion process. This raises the temperature of explosion products cloud to the adiabatic flame temperature ({approx}3,000K). Again, the JWL function provides no information on the combustion products states.
Date: October 16, 2009
Creator: Kuhl, A L
Partner: UNT Libraries Government Documents Department

GEOMETRY, HEAT REMOVAL AND KINETICS SCOPING MODELS FOR HYDROGEN STORAGE SYSTEMS

Description: It is recognized that detailed models of proposed hydrogen storage systems are essential to gain insight into the complex processes occurring during the charging and discharging processes. Such insight is an invaluable asset for both assessing the viability of a particular system and/or for improving its design. The detailed models, however, require time to develop and run. Clearly, it is much more efficient to begin a modeling effort with a good system design and to progress from that point. To facilitate this approach, it is useful to have simplified models that can quickly estimate optimal loading and discharge kinetics, effective hydrogen capacities, system dimensions and heat removal requirements. Parameters obtained from these models can then be input to the detailed models to obtain an accurate assessment of system performance that includes more complete integration of the physical processes. This report describes three scoping models that assess preliminary system design prior to invoking a more detailed finite element analysis. The three models address the kinetics, the scaling and heat removal parameters of the system, respectively. The kinetics model is used to evaluate the effect of temperature and hydrogen pressure on the loading and discharge kinetics. As part of the kinetics calculations, the model also determines the mass of stored hydrogen per mass of hydride (in a particular reference form). As such, the model can determine the optimal loading and discharge rates for a particular hydride and the maximum achievable loading (over an infinite period of time). The kinetics model developed with the Mathcad{reg_sign} solver, runs in a mater of seconds and can quickly be used to identify the optimal temperature and pressure for either the loading or discharge processes. The geometry scoping model is used to calculate the size of the system, the optimal placement of heat transfer elements, and the ...
Date: November 16, 2007
Creator: Hardy, B
Partner: UNT Libraries Government Documents Department

HYDROGEN GENERATION FROM SLUDGE SAMPLE BOTTLES CAUSED BY RADIOLYSIS AND CHEMISTRY WITH CONCETNRATION DETERMINATION IN A STANDARD WASTE BOX (SWB) OR DRUM FOR TRANSPORT

Description: A volume of 600 mL of sludge, in 4.1 L sample bottles (Appendix 7.6), will be placed in either a Super Pig (Ref. 1) or Piglet (Ref. 2, 3) based on shielding requirements (Ref. 4). Two Super Pigs will be placed in a Standard Waste Box (SWB, Ref. 5), as their weight exceeds the capacity of a drum; two Piglets will be placed in a 55-gallon drum (shown in Appendix 7.2). The generation of hydrogen gas through oxidation/corrosion of uranium metal by its reaction with water will be determined and combined with the hydrogen produced by radiolysis. The hydrogen concentration in the 55-gallon drum and SWB will be calculated to show that the lower flammability limit of 5% hydrogen is not reached. The inner layers (i.e., sample bottle, bag and shielded pig) in the SWB and drum will be evaluated to assure no pressurization occurs as the hydrogen vents from the inner containers (e.g., shielded pigs, etc.). The reaction of uranium metal with anoxic liquid water is highly exothermic; the heat of reaction will be combined with the source term decay heat, calculated from Radcalc, to show that the drum and SWB package heat load limits are satisfied. This analysis does five things: (1) Estimates the H{sub 2} generation from the reaction of uranium metal with water; (2) Estimates the H{sub 2} generation from radiolysis (using Radcalc 4.1); (3) Combines both H{sub 2} generation amounts, from Items 1 and 2, and determines the percent concentration of H{sub 2} in the interior of an SWB with two Super Pigs, and the interior of a 55-gallon drum with two Piglets; (4) From the combined gas generation rate, shows that the pressure at internal layers is minimal; and (5) Calculates the maximum thermal load of the package, both from radioactive decay of the ...
Date: March 30, 2010
Creator: DL, RILEY; AE, BRIDGES & WS, EDWARDS
Partner: UNT Libraries Government Documents Department

Heat of hydration of double-shell slurry feed grouts

Description: Samples of double-shell slurry feed (DSSF) grout (used in solidifying the waste stored in DS tanks at Hanford) were prepared and tested in adiabatic calorimeters to determine the effect of waste concentration and dry blend variations on the heat of hydration. Changes in DSSF waste concentration had the greatest impact on the overall heat of hydration of the grouts. Grouts prepared with dilute (100 times) DSSF had temperature rises up to 37 C less than with grouts prepared that for undiluted DSSF (15 C vs 52 C). All the grouts prepared with undiluted DSSF had temperature rises that exceeded 45 C. Partial neutralization of the DSSF with acids resulted in delayed reactions and lower temperature rises than that occurring in the reference grout. The temperature rise of a DSSF grout prepared with waste partially neutralized with HCl was 28 C after 300 hr hydration. Temperature rise for a grout made with DSSF partially neutralized with H3PO4 was 43 C. These values compare with a temperature rise of >52 C for a grout made with untreated DSSF. Decreasing the mix ratio from 9 lb/gal to 7.5 lb/gal did not significantly reduce the adiabatic temperature rise of grouts prepared with partially neutralized DSSF waste.
Date: December 1, 1992
Creator: Lokken, R.O.
Partner: UNT Libraries Government Documents Department

Corrosion and pyrophoricity of ZPPR fuel plates: Implications for basin storage

Description: This paper presents the results of recent experimentation and analysis of the pyrophoric behavior of corroded Zero Power Physics Reactor (ZPPR) HEU fuel plates and the implications of these results for the handling, drying, and passivation of uranium metal fuels stored in water basins. The ZPPR plates were originally clad in 1980; crevice corrosion of the uranium metal in a dry storage environment has occurred due to the use of porous cladding end plugs. The extensive corrosion has resulted in bulging and, in some cases, breaching of the cladding over a 15 year storage period. Processing of the plates has been initiated to recover the highly enriched uranium metal and remove the storage vulnerability identified with the corroded plates, which have been shown to contain significant quantities of the pyrophoric compound uranium hydride (UH{sub 3}). Experiments were undertaken to determine effective passivation techniques for the corrosion product; analysis and modeling was performed to determine whether heat generated by rapid hydride re-oxidation could ignite the underlying metal plates. The results of the initial passivation experiment showed that simple exposure of the hydride-containing corrosion product to an Ar-3 vol.% O{sub 2} environment was insufficient to fully passivate the hydride--flare-up of the product occurred during subsequent vigorous handling in air. A second experiment demonstrated that corrosion product was fully stable following grinding of the product to a fine powder in the Ar-3 vol.% O{sub 2} atmosphere. Numerical modeling of a corroded plate indicated that ignition of the plate due to the heat from hydride re-oxidation was likely if hydride fractions in the corrosion product exceeded 30%.
Date: April 1, 1997
Creator: Totemeier, T.C.; Hayes, S.L.; Pahl, R.G. & Crawford, D.C.
Partner: UNT Libraries Government Documents Department

Thermal properties and chemical reactivity. Quarterly report, January--March, 1970

Description: A method using a chromatograph for a quantitative determination of the FEFO content of LX-09 was investigated. The accuracy of the initial results was variable. Difficulty has been experienced in obtaining reproducible data due to fluctuations of unknown origin in the FEFO peak. Results are given of a sample analysis of LX-09. A modification of the procedure for determining purity with the DSC-1 is discussed. The molar heats of decomposition of PETN, diPEHN, triPEON, and tetraPEDN were measured and correlated with the number of nitrate and ether branches present in each type of molecule and the effective contribution of each branch to the total heat of decomposition was obtained. The heats of fusion and decomposition for each compound are reported.
Date: December 31, 1970
Creator: Wilson, R.S.
Partner: UNT Libraries Government Documents Department

Theoretical Energy Release of Thermites, Intermetallics, and Combustible Metals

Description: Thermite mixtures, intermetallic reactants, and metal fuels have long been used in pyrotechnic applications. Advantages of these systems typically include high energy density, high combustion temperature, and a wide range of gas production. They generally exhibit high temperature stability and possess insensitive ignition properties. For the specific applications of humanitarian demining and disposal of unexploded ordnance, these pyrotechnic formulations offer additional benefits. The combination of high thermal input with low brisance can be used to neutralize the energetic materials in mines and other ordnance without the "explosive" high-blast-pressure events that can cause extensive collateral damage to personnel, facilities, and the environment. In this paper, we review the applications, benefits, and characteristics of thermite mixtures, intermetallic reactants, and metal fuels. Calculated values for reactant density, heat of reaction (per unit mass and per unit volume), and reaction temperature (without and with consideration of phase changes and the variation of specific heat values) are tabulated. These data are ranked in several ways, according to density, heat of reaction, reaction temperature, and gas production.
Date: May 14, 1999
Creator: Fischer, S.H. & Grubelich, M.C.
Partner: UNT Libraries Government Documents Department

A DTA, TGA, and Metallurgical Study of the Exothermic Reactions Between Aluminum and Uranium Compounds: The Solid State Reactions of Uranium Oxides and Uranates with Aluminum

Description: Because recent experience at the Savannah River Plant revealed the pseudo-hexagonal uranates Na2U2O7 and Na6U7O2 will react exothermically in the solid state with aluminum, a systematic thermal study of the aluminothermic reactions of the three crystal classes of uranates and their relationships was begun at the Savannah River Laboratory. This paper discusses that study.
Date: October 23, 2001
Creator: Gray, L.W.
Partner: UNT Libraries Government Documents Department