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Oxidation behavior and microstructural decomposition of Ti-6Al-4V and Ti-6Al-4V-1B sheet

Description: This article conducts a direct comparison between the oxidation behavior of Ti-6Al-4V and Ti-6Al-4V + 1B to elucidate whether the addition of boron to Ti-^Al-4V impacts the oxidation behavior.
Date: August 1, 2016
Creator: Brice, David. A.; Samimi, P.; Ghamarian, I.; Liu, Yue; Brice, R. M.; Reidy, Richard F. et al.
Partner: UNT College of Engineering

Thermal Decomposition of Some Group I, II, and III Metal Alkyls

Description: Memorandum presenting a mechanism for the thermal decomposition of sodium, lithium, beryllium, magnesium, aluminum, and boron alkyls and for the reverse reaction, the addition of olefins to metal hydrides. The reactions are shown to be nonradical and to probably proceed through a cyclic intermediate.
Date: February 15, 1957
Creator: Rosenblum, Louis
Partner: UNT Libraries Government Documents Department

Caustic Treatment of Zircon in the Preparation of Pure Zirconium Compounds

Description: From abstract: This investigation was conducted in order to develop a process whereby the most abundant zirconium ore, namely zircon, could economically be put into solution and purified adequately for use in hafnium separation processes employing liquid-liquid extraction. Secondary aims concerned the preparation of pure zirconyl chloride, zirconyl nitrate, zirconyl sulfate, and zirconium oxide from the zircon ore.
Date: June 23, 1953
Creator: Spink, Donald R. & Wilhelm, Harley A.
Partner: UNT Libraries Government Documents Department

Aqueous solubilities and water induced transformations of halogenated benzenes

Description: Methods of determining the aqueous solubilities of twelve chlorinated benzenes were evaluated in pure and in different water matrices. In pure water, results were comparable with the calculated values. Higher chlorinated tetrachlorobenzenes (TeCBs), pentachlorobenzenes (PCBz), and hexachlorobenzenes (HCBs) gave better precision and accuracy than lower chlorinated monochlorobenzenes (MCBs), dichlorobenzenes (DCBs), or trichlorobenzenes (TCBs).
Date: August 1989
Creator: Kim, In-Young
Partner: UNT Libraries

A Partial Characterization of Upper Semi-Continuous Decompositions

Description: The goal of this paper is to characterize, at least partially, upper semi-continuous decompositions of topological spaces and the role that upper semi-continuity plays in preserving certain topological properties under decomposition mappings. Attention is also given to establishing what role upper semi-continuity plays in determining conditions under which decomposition spaces possess certain properties. A number of results for non-upper semi-continuous decompositions are included to help clarify the scope of the part upper semi-continuity plays in determining relationships between topological spaces and their decomposition spaces.
Date: December 1973
Creator: Dennis, William Albert
Partner: UNT Libraries

Base Effects on the Thermal Decomposition of Sec-butyllithium Solutions

Description: The pyrolysis of sec-butyllithium in solution was studied in an attempt to understand the loss of stereo-specificity and the atypical kinetics that have been reported. Additionally, the effect of added lithium alkoxides was studied to determine their effects on the highly reactive sec-butyllithium substrate.
Date: June 1966
Creator: Adams, George Michael
Partner: UNT Libraries

Investigation of effects of additives on storage properties of fuming nitric acids

Description: Report presenting a study of the storage properties of fuming nitric acids, with and without additives, at 170 degrees F in closed containers of aluminum bodies and steel caps. The effects on the storage properties indicated that the potassium fluoride dihydrate is most effective in reducing the rate of pressure rise and reducing corrosion on aluminum and stainless steel surfaces.
Date: December 8, 1952
Creator: Feiler, Charles E. & Morrell, Gerald
Partner: UNT Libraries Government Documents Department


Description: A simplified model for solids deposition in the pot calcination of waste was analyzed, and numerical calculations were made. In long calcination pots of 10 to 12 in. diameter, calcination times should not exceed 24 hours and might be as low as three hours if the pot is kept full. If the pots are fed at a constant rate, the cake might form with a steady state V'' when viewed in vertical section which would progress from bottom to top. Cake deposition rates appear to be independent of pot radius. Several advantages to using larger diameter pots are discussed. (auth)
Date: March 23, 1959
Creator: Whatley, M.E. & Perona, J.J.
Partner: UNT Libraries Government Documents Department


Description: The thermal decomposition of unirradiated and heavily reactor irradiated colloidal alpha -PbN/sub 6/ was studied in the temperature range 195 to 253 deg C and 173 to 239 deg C, respectively. The irradiation vastly reduces the induction and acceleratory periods found with unirradiated material and increases the maximum rate and the rate of the final decay. The maximum rate normally occurs at about 40% decomposition but is shifted to approximately zero time on irradiation. The change in decay rate on irradiation is demonstrated by the two rate constants for decay, k (unirradiated) = 10/sup 12.0 plus or minus 1.0/ exp (-38.3 plus or minus 2.3 kc/m/RT) and k (irradiated) = 10/sup 7.9 plus or minus 1.0/ exp (-25.7 plus or minus 2.4 kc/m/RT). The significant drop in activation energy is possibly associated with changes in electronic excitation energies, while the drop in frequency factor is thought to result from gross structaral changes accompanying the irradiation. The power laws observed in the acceleratory region are interpreted in terms of simultaneous surface and 3- dimensional reactions. (auth)
Date: October 31, 1963
Creator: Jach, J.
Partner: UNT Libraries Government Documents Department

Influence of Cr Substitution and Temperature on Hierarchical Phase Decomposition in the AlCoFeNi High Entropy Alloy

Description: This article investigates the length scale of the decomposition into a two-phase mixture of ordered B22 and disordered BCC solid solution as determined by the combination of composition and annealing temperature.
Date: October 22, 2018
Creator: Chaudhary, V.; Gwalani, Bharat; Soni, V.; Ramanujan, R. V. & Banerjee, Rajarshi
Partner: UNT College of Engineering

Factors Affecting the Precipitation of Uranium Peroxide

Description: Abstract: "This is a compilation of the data on uranium peroxide precipitations appearing in several reports. The solubility product is measured. The effect of many individual ions on the hydrogen peroxide decomposition rate and the complexing of uranium is demonstrated. Studies on plant and other highly contaminated solutions are not included."
Date: July 8, 1946
Creator: Mogg, D. W. & Larson, C. E.
Partner: UNT Libraries Government Documents Department

Photo-fragmentation of the closo-carboranes Part 1: Energetics of Decomposition

Description: The ionic fragmentation following B 1s and C 1s excitation of three isomeric carborane cage compounds [closo-dicarbadodecaboranes: orthocarborane (1,2-C2B10H12), metacarborane (1,7-C2B10H12), and paracarborane (1,12-C2B10H12)], is compared with the energetics of decomposition. The fragmentation yields for all three molecules are quite similar. Thermodynamic cycles are constructed for neutral and ionic species in an attempt to systemically characterize single ion closo-carborane creation and fragmentation processes. Lower energy decomposition processes are favored. Among the ionic species, the photon induced decomposition isdominated by BH+ and BH2+ fragment loss. Changes in ion yield associated with core to bound excitations are observed.
Date: November 9, 2007
Creator: Kilcoyne, Arthur L; Feng, Danqin; Liu, Jing; Hitchcock, Adam P.; Kilcoyne, A.L. David; Tyliszczak, Tolek et al.
Partner: UNT Libraries Government Documents Department

The Decomposition of Human-Written Book Summaries

Description: In this paper, the authors evaluate the extent to which human-written book summaries can be obtained through cut-and-paste operations from the original book. The authors analyze the effect of the parameters involved in the decomposition algorithm, and highlight the distinctions in coverage obtained for different summary types.
Date: March 2009
Creator: Ceylan, Hakan & Mihalcea, Rada, 1974-
Partner: UNT College of Engineering

The FB-Line and F-Canyon HAN/Nitric Acid Decomposition Study

Description: Separations requested SRTC study the autocatalytic decomposition of the hydroxylamine nitrate which may occur in the presence of concentrated nitric acid with respect to making-up cold feed solutions. The data obtained from this study will provide Separations an envelope within which safe operations can be conducted.
Date: August 19, 1998
Creator: Hang, T.
Partner: UNT Libraries Government Documents Department

Copper Catalyzed Sodium Tetraphenylborate, Triphenylborane, Diphenylborinic Acid and Phenylboronic Acid Decomposition Kinetic Studies in Aqueous Alkaline Solutions

Description: This work studied the kinetics of copper-catalyzed decomposition of tetraphenylborate, triphenylborane, diphenylborinic acid and phenylboronic acid (NaTPB, 3PB, 2PB and 1PB, respectively) in aqueous alkaline solution over the temperature range of 25 to 70 degrees C. The statistically designed test matrices added copper sulfate to maximum concentrations of 10 mg/L. The relative rates of decomposition increase in the order of NaTPB < 1PB {tilde} 3PB < 2PB. Dependence of decomposition on the amount of added copper increases in the order of 3PB {tilde} 2PB < 1PB {tilde} NaTPB. Activation energies ranged from 82 to 143 kJ/mole over the temperature range studied. Final decomposition products predominately involved benzene and phenol. All 3PB, 2PB and 1PB intermediate phenylborate species proved relatively stable (< 8 percent decomposition over {tilde} 500 h) towards thermal hydrolysis in 1.5 M NaOH when contained in carbon-steel vessels sealed under air at ambient temperature (23 - 25 degrees C) with no added copper. Measurable (> 10-7 Mh-1) thermal hydrolysis of the phenylborate species occurs at 55 to 70 degrees C in alkaline (0.6-2.3 M OH-, 2-4.7 M Na+) solution with no added copper. The experiments suggest an important role for oxygen in copper-catalyzed phenylborate decomposition. NaTPB decomposes promptly under anoxic conditions while 3PB, 2PB and 1PB decompose faster in aerobic solutions. Benzene and phenol form as the predominant end-products from alkaline copper catalysis in static systems sealed under air. Both 2PB and 1PB decompose with near equal rates and quantitatively produce phenol under flowing air-purge conditions at 25 to 60 degrees C. Mechanisms for copper-catalyzed phenylborate decomposition likely involve a redox process giving loss of a phenyl group from the phenylborate with reduction of cupric ion, or dephenylation by reduced cuprous ion involving a phenylated copper intermediate.
Date: March 15, 1999
Creator: Crawford, C.L.
Partner: UNT Libraries Government Documents Department