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Basic Chemical Thermodynamics and Kinetics
Published in Kalliat T. Valsaraj, Elizabeth M. Melvin, Principles of Environmental Thermodynamics and Kinetics, 2018
Kalliat T. Valsaraj, Elizabeth M. Melvin
Reactions in the environment are complex in nature, consisting of several steps. Empirical rate laws determined through experiments can give us ideas about the underlying mechanisms of these complex reactions (Moore and Pearson, 1981). It is best illustrated using a reaction, which admittedly has only limited significance in environmental engineering. The reaction is the formation of hydrogen halides from its elements. The hydrogen halides do play a central role in the destruction of ozone in the stratosphere through their involvement in the reaction of ozone with chlorofluorocarbons. Several introductory physical chemistry textbooks use this reaction as an illustration of complex reactions. Hence, only a cursory look at the essential concept is intended, namely, that of the deduction of reaction mechanism from knowledge of the rate law for the formation of a hydrogen halide.
Interfacial Catalysis at Oil/Water Interfaces
Published in Alexander G. Vdlkdv, Interfacial Catalysis, 2002
B-Elimination of hydrogen halide, induced by organic anions, generated in PT catalyzed systems, is often a first step of many synthetically useful reactions. Ring open- ing of 1,1,2-trihalocyclopropanes with formation of acetylene derivatives serves as an example.
Green synthesis of ionic liquid mediated neodymium oxide nanoparticles via Couroupita guianensis abul leaves extract with its biological applications
Published in Journal of Biomaterials Science, Polymer Edition, 2022
Veerasingam Muthulakshmi, Chinnalagu Dhilip Kumar, Mahalingam Sundrarajan
Ionic liquids (ILs) are well known as molten salt, containing the metal legating group which easily finds use in the extraction of metal ions from a covalently attached functional group. It performs not just as reactive media but also as a designer solvent [16]. All ILs are stable because of the strong basicity of imidazole, which reduces hydrogen halide. The significant role of ILs as a catalyst, by which it controls the reaction depending on the functional group attached to cations and anions [17]. So ILs may behave as acidic, basic or organocatalyst, provide a hydrophobic and hydrophilic region, then high directional polarizability, stability and low toxicity. A solvent free protocol has slight ties with inactivity and control on surface morphology of Nd2O3 NPs [18,19].
Halogenation of used aluminum matrix test reactor fuel – a bench-scale demonstration with surrogate materials
Published in Journal of Nuclear Science and Technology, 2022
Steven D. Herrmann, Haiyan Zhao, Meng Shi, Matthew M. Jones, Michael N. Patterson
Regarding the extension of this halogenation technique to the use of ATR fuel, the simplifying portions of this study need to be addressed. First, ammonium halides were used out of convenience in this study to deliver a hydrogen halide gas to the reactive metals without installing a dedicated gaseous hydrogen halide system. In the halogenation of the used ATR fuel, a gaseous halogenation system would be preferable. As such, ammonia gas would not be present in the off-gas system, as it was in this study. Second, neodymium metal was used in this study as a surrogate for uranium metal. Neodymium forms intermetallics with aluminum (e.g. NdAl2), as does uranium. However, no prepared neodymium and aluminum intermetallics were used in this study because they were expected to halogenate completely, as was observed in the previous work with uranium and aluminum intermetallics [17–20] and as shown in the following chlorination reaction [10].
Relativistic electron detachment energies and spin–orbit splittings from quasiparticle electron propagator calculations
Published in Molecular Physics, 2020
Filip Pawłowski, Joseph Vincent Ortiz
Errors in P3+ ionisation energies of inert–gas atoms and hydrogen halide molecules and electron detachment energies of anions are displayed in Figure 1. (Experimental data [19] are listed in Table 1; data on anions are inferred from atomic excitation energies [50–53] and electron affinities [54–56].) At the double ζ level, underestimates of 0.3–0.5 eV occur for species of the third and fourth periods (red and blue lines in Figure 1, respectively). These errors are diminished at the triple ζ level, giving underestimates of 0.1–0.2 eV. Quadruple ζ results continue this trend: unsigned errors obtained at this level become smaller than 0.1 eV. Basis–set saturation is not yet achieved at the quadruple ζ level; CBS results (placed at 14, where they first match the asymptotic region of the inverse cubic fitting curve defined by Equation (7) of Ref. [47]) overestimate electron binding energies by about 0.1 eV on average. Quadruple ζ results underestimate the CBS limits by 0.1 eV on average. SO splittings for the third and fourth periods are in agreement with experiment to within 10%.