Kinetics of CO2 formation in thermal destruction of brown coals

The previously suggested approach to the problem of kinetic system identification /1/ was used for the system of independent first order reactions. The analysis of the curves of CO₂ formation in thermal destruction of brown coal indicates that both structure and model parameters of real processs can be identified in terms of the continuity concepts.

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(I) ë . CO₂ , , .

     

Catalytic conversion of dimethylsulfide to methylmercaptan

The effect of reaction conditions on the methylmercaptan formation from dimethylsulfide in H₂S catalyzed by -Al₂O₃ has been studied. The reaction is first order with respect to dimethylsulfide. It has been revealed that the maximum activity in this reaction is observed for the catalysts whose surface contains a large number of aprotonic acid centers and moderate-strength basic sites.

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-Al₂O₃. , . . , , .

     

Workflow to Investigate Subtle Differences in Wine Volatile Metabolome Induced by Different Root Systems and Irrigation Regimes

To allow for a broad survey of subtle metabolic shifts in wine caused by rootstock and irrigation, an integrated metabolomics-based workflow followed by quantitation was developed. This workflow was particularly useful when applied to a poorly studied red grape variety cv. Chambourcin. Allowing volatile metabolites that otherwise may have been missed with a targeted analysis to be included, this approach allowed deeper modeling of treatment differences which then could be used to identify important compounds. Wines produced on a per vine basis, over two years, were analyzed using SPME-GC-MS/MS. From the 382 and 221 features that differed significantly among rootstocks in 2017 and 2018, respectively, we tentatively identified 94 compounds by library search and retention index, with 22 confirmed and quantified using authentic standards. Own-rooted Chambourcin differed from other root systems for multiple volatile compounds with fewer differences among grafted vines. For example, the average concentration of β-Damascenone present in own-rooted vines (9.49 µg/L) was significantly lower in other rootstocks (8.59 µg/L), whereas mean Linalool was significantly higher in 1103P rootstock compared to own-rooted. β-Damascenone was higher in regulated deficit irrigation (RDI) than other treatments. The approach outlined not only was shown to be useful for scientific investigation, but also in creating a protocol for analysis that would ensure differences of interest to the industry are not missed.     

Pathways of Acetol Formation in the Course of Production of Phenol and Acetone by Cleavage of Cumyl Hydroperoxide

The mechanism of acetol formation in two-stage process of sulfuric acid cleavage of cumyl hydroperoxide was studied and confirmed by comparison with related reaction systems.     

The Synthesis of Crystals of Chalcogenides of K,Zr, Hf,Hg, and Some Other Elements in Halide Melts under Conditions of Stationary Temperature Gradient

Crystallography Reports - The growth of crystals of metals, alloys, chalcogenides, and pnictides in melts of alkali metal halides under conditions of stationary temperature gradient has been...     

Effect of Oxygen on the Quantum,Magnetic, and Thermodynamic Properties of Co Nanowires on the Reconstructed Anisotropic (1 × 2)/Au(110) and (1 × 2)/Pt(110) Surfaces: Ab Initio Approach

Ab initio theoretical study of the quantum magnetic properties of Co nanowires on the pure and oxygen-reconstructed (1 × 2)/Au(110) and (1 × 2)/Pt(110) surfaces is performed. Their structures and electronic configurations are calculated using the electron density functional theory. High values of magnetic moment and magnetic anisotropy energies of Co atoms are found on both pure and oxygen-reconstructed (1 × 2)/Au(110) and (1 × 2)/Pt(110) surfaces. The adsorption of oxygen atoms on the (1 × 2)/Au(110) substrate is shown to affect the structural arrangement of Co nanowire atoms on this substrate and to increase the magnetic anisotropy energy (by 1.91 meV per nanowire atom). The adsorption of oxygen on the Pt(110) substrate substantially decreases the magnetic anisotropy energy of the Co nanowire on it (by 5.98 meV per atom). The origin of these changes is revealed by analyzing the local densities of states of the d electrons of nanowire atoms. The temperature ranges of the states with the lowest free surface energy are determined using the atomistic thermodynamics methods. These data and the available experimental data are used to predict the possibility of observing the structures under study in experiments.     

Experimental observation of different-order components of a vibrational wave packet in a bulk dielectric using high-order Raman scattering

We use high-order Raman scattering in a bulk dielectric to characterize coherent dynamics with precision typical for gas phase experiments. The experimental pump-probe approach allows for the simultaneous observation and separation in space and time of the individual contributions of different-order Raman processes to a coherent wave packet without relying on phase-matching conditions and within the same experimental geometry. We propose a novel technique to discriminate between stimulated excitation of vibronic levels in the impulsive and intermediate excitation regimes, futhermore allowing us to distinguish between different pathways contributing to the same fifth-order Raman processes.