Some aspects of mathematical and chemical modeling of complex chemical processes

Some theoretical questions involved in the mathematical modeling of the kinetics of complex chemical process are discussed. The analysis is carried out for the homogeneous oxidation of ethylbenzene in the liquid phase. Particular attention is given to the determination of the general characteristics of chemical systems from an analysis of mathematical models developed on the basis of linear algebra

The Ion-Exchange between Zn++ and Cd++ on Synthetic Zeolite of Type A

From ion-exchange isotherm at 10 and 25° C the following thermodynamic data for the reaction Cd++ (aq) + ZnZ (s) ~ CdZ (s) + +Zn++ (aq), have been obtained: log K2ss = 0.354; log K298 = 0.33s; A H~98 = - 0.57 ± 0.15 kcal/mo! and A S~8 = - 0.4 ± 0.2 cal/mol K. The results are consistent with the data on Cd++ - Na• and Zn++ - Na• exchanges and confirm that the three counter-ions Na+, Cd++ and zn++ exchange reversibly, independently of the initial composition of the A-zeolite

On Some Geometric Properties of Slice Regular Functions of a Quaternion Variable

The goal of this paper is to introduce and study some geometric properties of slice regular functions of quaternion variable like univalence, subordination, starlikeness, convexity and spirallikeness in the unit ball. We prove a number of results, among which an Area-type Theorem, Rogosinski inequality, and a Bieberbach-de Branges Theorem for a subclass of slice regular functions. We also discuss some geometric and algebraic interpretations of our results in terms of maps from $\mathbb R^4$ to itself. As a tool for subordination we define a suitable notion of composition of slice regular functions which is of independent interest

Conditional BRUNO: A neural process for exchangeable labelled data

We present a neural process that models exchangeable sequences of high-dimensional complex observations conditionally on a set of labels or tags. Our model combines the expressiveness of deep neural networks with the data-efficiency of Gaussian processes, resulting in a probabilistic model for which the posterior distribution is easy to evaluate and sample from, and the computational complexity scales linearly with the number of observations. The advantages of the proposed architecture are demonstrated on a challenging few-shot view reconstruction task which requires generalisation from short sequences of viewpoints

The Exchange of Tritiated Water Between Zn-A Zeolitevand the Surrounding Water

Zeolites are considered as adsorbents for tritiated waste water. The sorption capacity of 4A zeolite is increased, and the speed of tritium release, as THO, decreased if sodium ions in 4A zeolite are replaced with small divalent cations. The exchange kinetics THO/H20 between Zn-A zeolite containing tritiated water and the surrounding water was investigated at 30-60 De, using zinc-exchanged 4A zeolite beads of 0.8 and 1.6 mm radius. The kinetics was controlled by the diffusion of water in the solid particle and interpreted in terrns of the Boyd - Reichenberg diffusion model. Effective self-diffusion coefficients of water in the zeolite beads were obtained and the kinetic data are discussed from the point of view of using zeolites as sorbents and storage material for tritiated waste water

Solvent Extraction of Vanadium (V) with N-Benzoyl-N-phenylhydroxylamine

N-Benzoyl-N-phenylhydroxylamine is a monomeric solute in chloroform which readily extracts vot from acidic aqueous solutions. The vanadium species extracted from concentrated aqueous acid solutions have a characteristic absorption band at 450-550 mμ. Solvent extraction experiments indicate that from aqueous 1-6 N HCl two vanadium species are extracted into chloroform. The compositions of these species correspond to the reagent: vanadium: chloride ratios of 2 : 1 : 1 and 3 : 1 : 1