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1.
The reactions of ten main group acidic oxides and oxyanions with molten alkali metal carbonate eutectics have been studied by thermogravimetry. Products have been identified by IR and Raman spectroscopy and stoichiometries suggested for the several reactions as oxide is progressively incorporated. Ultimately the tetrahedral ortho-oxyanion was formed except with the less acidic oxides (As2O3, Sb2O3, SiO2). Sulphite was partially oxidised by the carbon dioxide atmosphere to sulphate. 相似文献
2.
The reactions of lanthanum(III), cerium(III), praseodymium(III) and europium(III) chlorides have been studied in the molten lithium nitrate-potassium nitrate and sodium nitrate-potassium nitrate eutectics. The ultimate reaction products have been shown to be oxides (La2O3, CeO2, Pr6O11 and Eu2O3, respectively) which increased the rate of decomposition of the melts, while in three cases an intermediate oxide nitrate was formed (LaONO3, PrONO3 and EuONO3). The temperatures and stoichiometries of the reactions have been established. 相似文献
3.
Molybdenum(VI) oxide, ammonium molybdate and molybdic acid reacted in molten sodium nitrite—potassium nitrite eutectic to form orthomolybdate, nitrogen dioxide and nitric oxide (with nitrate as a secondary product), a more polymerised polymolybdate being formed as an intermediate product. Tungsten(VI) oxide reacted similarly but less rapidly. Molybdenum and tungsten metals reacted to form the orthoxyanion and nitrogen, the latter metal reacting considerably faster and forming smaller amounts of nitric oxide and nitrous oxide. Reaction temperatures and stoichiometries are given and reaction pathways suggested. 相似文献
4.
Thomas Pugh Andrew Kerridge Richard A. Layfield 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2015,127(14):4329-4332
Deprotonation of the yttrium–arsine complex [Cp′3Y{As(H)2Mes}] ( 1 ) (Cp′=η5‐C5H4Me, Mes=mesityl) by nBuLi produces the μ‐arsenide complex [{Cp′2Y[μ‐As(H)Mes]}3] ( 2 ). Deprotonation of the As H bonds in 2 by nBuLi produces [Li(thf)4]2[{Cp′2Y(μ3‐AsMes)}3Li], [Li(thf)4]2[ 3 ], in which the dianion 3 contains the first example of an arsinidene ligand in rare‐earth metal chemistry. The molecular structures of the arsine, arsenide, and arsinidene complexes are described, and the yttrium–arsenic bonding is analyzed by density functional theory. 相似文献
5.
W. E. Garner C. A. Waters H. Lüers C. W. G. Hetterschy Aristides Kanitz F. Liebert A. Uhl W. Kestranek J. M. Kolthoff B. D. Hartong J. Pinkhof E. Biilmann A. Klit F. Haber Z. Klemensiewicz W. S. Hughes A. L. v. Steiger W. E. L. Brown Phyllis M. T. Kerridge Th. Arnd W. Siemers K. H. Goode W. D. Treadwell J. W. Williams Th. A. Whitenack U. Ehrhardt und E. Linde 《Fresenius' Journal of Analytical Chemistry》1930,80(5-6):203-213
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6.
Concomitant Carboxylate and Oxalate Formation From the Activation of CO2 by a Thorium(III) Complex
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Alasdair Formanuik Dr. Fabrizio Ortu Christopher J. Inman Dr. Andrew Kerridge Dr. Ludovic Castro Prof. Laurent Maron Dr. David P. Mills 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(50):17976-17979
Improving our comprehension of diverse CO2 activation pathways is of vital importance for the widespread future utilization of this abundant greenhouse gas. CO2 activation by uranium(III) complexes is now relatively well understood, with oxo/carbonate formation predominating as CO2 is readily reduced to CO, but isolated thorium(III) CO2 activation is unprecedented. We show that the thorium(III) complex, [Th(Cp′′)3] ( 1 , Cp′′={C5H3(SiMe3)2‐1,3}), reacts with CO2 to give the mixed oxalate‐carboxylate thorium(IV) complex [{Th(Cp′′)2[κ2‐O2C{C5H3‐3,3′‐(SiMe3)2}]}2(μ‐κ2:κ2‐C2O4)] ( 3 ). The concomitant formation of oxalate and carboxylate is unique for CO2 activation, as in previous examples either reduction or insertion is favored to yield a single product. Therefore, thorium(III) CO2 activation can differ from better understood uranium(III) chemistry. 相似文献
7.
Using KCl/ZnSO4 eutectic it has been shown that cooling the melt into a room temperature enclosure forms a lamellar structure, whereas cooling into a heated enclosure (225 °C) forms a conglomerate structure, while an enclosure temperature of 125 °C gave a partially conglomerate structure with some lamellae in process of forming conglomerates.Consideration of the thermal gradients imposed on solidification and consequently the relative time available during which the ions are sufficiently mobile to rearrange their positions, can explain the observation that lamellar structures are formed by higher melting point eutectics, whereas eutectics of lower melting point form conglomerate structures. 相似文献
8.
ter Steege DH Smits M de Lange CA Westwood NP Peel JB Visscher L 《Faraday discussions》2000,(115):259-69; discussion 303-30
A (2 + 1) one-colour resonance-enhanced multiphoton ionisation study is carried out on the C 2 sigma- state of the ClO radical in the one-photon energy range 29,500-31,250 cm-1. The ClO radical is produced by one-photon photolysis of ClO2 employing 359.2 nm photons derived from a separate laser. In this way a significant concentration of vibrationally excited ClO in its spin-orbit split X 2 pi omega (omega = 3/2 or 1/2) electronic ground state is produced. In addition to mass-resolved excitation spectra, kinetic-energy resolved photoelectron spectra for the X 3 sigma-(v+)<--C 2 sigma-(v' = 3-5) transitions are measured. These transitions are not completely Frank-Condon diagonal, and indicate a decrease in bond length on removal of the Rydberg electron from the C 2 sigma- state. In addition to an unambiguous assignment of the C 2 sigma- state, valuable information is obtained on the degree of vibrational excitation with which the nascent ClO radical is formed in the photolysis of ClO2. Analysis of the photoelectron spectra is supported by Franck-Condon calculations based on potential energy curves either from experimental spectroscopic parameters, or obtained by theoretical ab initio methods. 相似文献
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10.
The design, fabrication, and testing of photoelastic models of double-lap, multiple-pin connectors are discussed. Interest
is in the stresses in the inner laps. These stresses are determined by constructing models with photoelastic inner laps and
transparent-acrylic outer laps. The connectors have two pins, in tandem, parallel to the load direction. A photoelastic-isotropic
point is shown to permit the evaluation of load sharing between the two pins. A numerical scheme, utilizing the isochromatic-
and isoclinic-photoelastic data and a finite-difference representation of the planestress equilibrium equations, is used to
compute the stresses around the two pins. Representative stress distributions and stress-concentration factors are shown. 相似文献