Thermal decomposition studied

It is worth noting that although PuFg(c) has not been characterized pentavalent fluorocomplexes are well known. In the hexava-lent state only oxyfluorocomplexes are known. However, thermodynamic data on these species are almost completely lacking. The thermal decomposition study (42J of the quadrivalent complex (NH4)4PuF8 according to scheme (10)... 

Owens C, Pytlewski LL, Mikulski CM, et al. 1979. X-ray crystallographic, morphological and thermal-decomposition studies of 2-1 adduces of diisopropyl methylphosphonate with stannous and stannic halides. Journal of Inorganic Nuclear Chemistry 41(9) 1261-1268. 

Magnetic susceptibility measurements have been made for the lanthanide complexes of 2,6-DMePyO (171), EPO, BPO, EAsO, BAsO (237, 238), and AAP (95). In all these cases, the measured magnetic susceptibilities agree with the free ion values. Dipole moment measurements have been carried out on complexes of the type Ln(TBP)3-(N03)3 (387, 388). ESR studies on Gd(AP)6 I3 (389) and thermal decomposition studies on the complexes of the lanthanides with DMSO (250), DPSO (250, 259), QNO (175), HOQNO (190), 18-crown-6 (132), 15-crown-5 (131), and gycine (390) have also been reported. 

Triethanolamine complexes of chromium(iii) have been reported and characterized in i.r. spectra and thermal-decomposition studies. The chromium(iii) nitrilotriacetato-complex [CrL(H20)2] [L = N(CH2C02)3 ] complexes with thallium(iii) to give [ CrL3(0H)(H20) gTl] with a formation constant of 9 3 X 10 at 25 The hydrolysis and dimerization of [CrLlOHljV ... 

In the thermal decomposition studies of the transient actinide homoalkyls, eUmination has been shown to be the dominant mechanism 133). 

Santhosh, G., Venkatachalam, S., Krishnan, K., Catherine, B. K., and Ninan, K. N., Thermal Decomposition Studies on Advanced Oxidiser Ammonium Dinitramide, Proceedings of the 3 rd International Conference on High-Energy Materials, Thiruvanan-thapuram, India, 2000. 

Interest in mercury(II) tetrazolates, notably Hg(5-02N-tta)2, as detonators (12, 190) has prompted thermal decomposition studies on mercury salts of 5-nitrotetrazole (34) and 5,5 -azotetrazole (169). Cycloaddition of methyl isocyanide to Hg(N3)2(PPh3)2 under mild conditions yields the C-bonded tetrazolate complex Hg(l-Me-tta)2 (15). Mercury(II) adducts HgX2(l,5-pmtta) (X = Cl, Br, or CN) and Hg(N03)2(l,5-pmtta)2 have been described (174, 236). 

Chloride. — All the rare earth trichlorides except La and Pr crystallize with six molecules of water of crystallization La and Pr chlorides crystallize as heptahydrates. Thermal decomposition studies [280] on... 

Thermal decomposition studies [469] indicate that the onset of weight loss for most of those complexes is rather abrupt. For the Eu3+-complex complete decomposition occurs between 400 and 500° C. 

The spiro sulfurane (121) has been prepared and its thermal decomposition studied [94AG(E)2094], Ring expansion of (122) affords (123) and the X-ray structures of both... 

M.J. Rossi, J.C. Bottaro, D.F. McMillen, Int. J. Chem.Kinet., 25 (1993) 549. M.J. Rossi, D.F. McMillen, D. M.Golden, Low Pressure Thermal Decomposition Studies Selected Nitramine and Dinitramine Energetic Materials ONR Final Report AD-A247 972 March 1992. 

NaC103 is stable to well above its melting point. Three thermal decomposition studies of liquid NaC103 have been published4074111 that agree in their main features. Decomposition starts near 400°C. No Cl2 and C102 are formed. The major reaction is... 

No thermodynamic data are available. The only thermal decomposition study is that of Bancroft and Gesser12 who found that decomposition, beginning near 250°C, goes almost entirely to the oxide ... 

Carbon dioxide and hydrogen also interact with the formation of surface formate. This was documented for ZnO by the IR investigation of Ueno et al. (117) and, less directly, by coadsorption-thermal decomposition study (84). Surface complex was formed from C02 with H2 at temperatures above 180°C, which decomposed at 300°C with the evolution of carbon monoxide and hydrogen at the ratio CO Hs 1 1. When carbon dioxide and hydrogen were adsorbed separately, the C02 and H2 desorption temperatures were different, indicating conclusively that a surface complex was formed from C02 and H2. A complex with the same decomposition temperature was obtained upon adsorption of formaldehyde and methanol. Based upon the observed stoichiometry of decomposition products and upon earlier reported IR spectra of C02 + H2 coadsorbates, this complex was identified as surface formate. Table XVI compares the thermal decomposition peak temperatures and activation energies, product composition, and surface... 

The thermal decomposition studies were initially carried out by following weight-loss as functions of time and temperature of the sample when under vacuum. When the lowest temperature for rapid weight-loss had been established it was our practice to hold the sample at this temperature until constant weight was attained. The volatiles were trapped at -196° and were subsequently examined by gas-phase Infrared spectroscopy. The residual solids in the Monel tubes were examined by X-ray powder photography, Raman and Infrared spectroscopy and were also tested for para- or diamagnetism. 

Hubbard, A. B., and W. E. Robinson, A thermal decomposition study of Colorado oil shale. Report of Investigations 4744, U.S. Department of the Interior, Bureau of Mines (1950). 

The author wishes to acknowledge the able technical assistance of David Santos and Gerald Wagner and helpful discussions with Med Colket and Daniel Seery. The thermal decomposition studies upon which this work was based were supported in part by grant No. AER75-17247 from the National Science Foundation. Additional work has been performed under contract No. ET-78-C-01-3167 with the U.S. Department of Energy. 

There has been speculation about the relationship between the exceptional thermal stability of these compounds and their molecular structure. Thermal decomposition studies show that the stability is associated with higti melting point and low vapour pressure and there is evidence that the rates of decom< position arc enhanced when substances are in liquid or vapour phase they reach a higher energy level when molten or vapourized (81. 

An important effort in this investigation was the thermal decomposition study of the shales. Considerable effort has been made to find a simple kinetic model which will accurately describe the weight loss curves for non-isothermal pyrolysis at various heating rates. In the past, many researchers have proposed and tested theoretical kinetic models for this reaction Q-4), however, most attempts at finding a suitable model have been focused on finding a very accurate fit to experimental data. Successive studies have increasingly emphasized microscopic details (i.e., diffusion models, exact chemical composition, etc.) in an attempt to find a precise model to fit the weight loss curves. In this... 

Hubbard, A. B. Robinson, W. E. "A Thermal Decomposition Study of Colorado Oil Shale," Report of Investigation 4744, Bureau of Mines, Washington, D.C., 1950. 

The Ahrrenius plot., figure 6, which is preliminary, shows time constants at three anneal temperatures. It suggests that, as with loss of crystallinity (ref. 5), there are two regimes of dehydroxylation with activation energies of 0.7 eV above and J3.4 eV below about 750°C. The latter value is not inconsistent with the activation energy of 4.3 eV for diffusion of framework aluminiums deduced from thermal decomposition studies (ref. 5). Further measurements are in progress. 

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