Hexa-μ-chlorido-hexa­chlorido(η6-hexa­methyl­benzene)trialuminium(III)lanthanum(III) benzene solvate

In the title compound, [Al3LaCl12(C12H18)]·C6H6, all mol­ecules are located on a mirror plane. Three chloridoaluminate groups and a hexa­methyl­benzene mol­ecule are bound to the central lanthanum(III) ion, forming a distorted penta­gonal bipyramid with the η6-coordinated arene located at the apical position. The hexa­methyl­benzene ligand disordered between two orientations in a 1:1 ratio is also involved in parallel-slipped π–π stacking inter­molecular inter­actions with a benzene solvent mol­ecule [centroid–centroid distance 3.612 (4) Å]

Zunderbildung beim Warmwalzen

Einleitung Motivation des Forschungsvorhabens Schwerpunkte der Arbeit Stand der Kenntnisse Ergebnisse und Zusammenfassun

Inactivation and Secondary Structure in the D4/S4-5 Region of the SkM1 Sodium Channel

The D4/S4-5 interhelical region plays a role in sodium channel fast inactivation. Examination of S4-5 primary structure in all domains suggests a possible amphipathic helical conformation in which a conserved group of small hydrophobic residues occupies one contiguous surface with a more variable complement of nonpolar and polar residues on the opposite face. We evaluated this potential structure by replacing each residue in D4/S4-5 of the rat SkM1 skeletal muscle sodium channel with substitutions having different side chain properties. Of the 63 mutations analyzed, 44 produced functional channels. P1473 was intolerant of substitutions. Nonpolar substitutions in the conserved hydrophobic region were functionally similar to wild type, while charged mutations in this region before P1473 were nonfunctional. Charged mutations at F1466, M1469, M1470, and A1474, located on the opposite surface of the predicted helix, produced functional channels with pronounced slowing of inactivation, shifted voltage dependence of steady-state inactivation, and increased rate of recovery from inactivation. The substituted-cysteine-accessibility method was used to probe accessibility at each position. Residues L1465, F1466, A1467, M1469, M1470, L1472, A1474, and F1476C were easily accessible for modification by sulfhydryl reagents; L1464, L1468, S1471, and L1475 were not accessible within the time frame of our measurements. Molecular dynamics simulations of residues A1458 to N1477 were then used to explore energetically favorable local structures. Based on mutagenesis, substituted-cysteine-accessibility method, and modeling results, we suggest a secondary structure for the D4/S4-5 region in which the peptide chain is α-helical proximal to P1473, bends at this residue, and may continue beyond this point as a random coil. In this configuration, the entire resultant loop is amphipathic; four residues on one surface could form part of the binding site for the inactivation particle

Knowledge and innovation dynamics of the Northwest Russia under geopolitical changes

Over the past 25 years, Russia has faced several economic and geopolitical challenges, including the 2008 global financial crisis, sanctions imposed in 2014, and the COVID-19 pandemic. To remain resilient in the face of these challenges, Russia needs to adopt a flexible development strategy and transition to a new path of development. This transition requires the development of new knowledge-intensive industries, expansion into promising markets, strengthening trade and economic partnerships, and achieving technological sovereignty. This study examines the innovation system in Northwest Russia and identifies factors that are critical for its sustainability and innovation security in the face of geopolitical instability. The study uses an integrated approach to trace the knowledge production and innovation process from research findings to the commercialization of new technologies. The study finds that there are strong correlations between innovation activity and R&D investment, patent activity, and the number of innovative organisations. The study also identifies three types of regional innovation systems in Northwest Russia: core, semi-periphery, and periphery. The nature of the regions' involvement in R&D determines the dynamics and specialization of their publications and patents. The study also finds that there is a positive correlation between the volume of innovative products and quantitative factors in the functioning of subsystems involved in knowledge generation and innovation. Finally, the study examines the geography and structure of the international research network that the regions of Northwest Russia had formed by 2022. It shows that the geopolitical transformation requires a significant part of cooperation ties with unfriendly countries to be restructured

Electronic structure and magnetic properties of the spin-1/2 Heisenberg system CuSe2O5

A microscopic magnetic model for the spin-1/2 Heisenberg chain compound CuSe2O5 is developed based on the results of a joint experimental and theoretical study. Magnetic susceptibility and specific heat data give evidence for quasi-1D magnetism with leading antiferromagnetic (AFM) couplings and an AFM ordering temperature of 17 K. For microscopic insight, full-potential DFT calculations within the local density approximation (LDA) were performed. Using the resulting band structure, a consistent set of transfer integrals for an effective one-band tight-binding model was obtained. Electronic correlations were treated on a mean-field level starting from LDA (LSDA+U method) and on a model level (Hubbard model). In excellent agreement of experiment and theory, we find that only two couplings in CuSe2O5 are relevant: the nearest-neighbour intra-chain interaction of 165 K and a non-frustrated inter-chain coupling of 20 K. From a comparison with structurally related systems (Sr2Cu(PO4)2, Bi2CuO4), general implications for a magnetic ordering in presence of inter-chain frustration are made.Comment: 20 pages, 8 figures, 3 table

Spectral structure of a polycapillary lens shaped X-ray beam

Polycapillary X-ray optics is widely used in X-ray analysis techniques to create a small secondary source, for instance, or to deliver X-rays to the point of interest with minimum intensity losses [1]. The main characteristics of the analytical devices on its base are the size and divergence of the focused or translated beam. In this work, we used the photon-counting pixel detector ModuPIX to study the parameters for polycapillary focused X-ray tube radiation as well as the energy and spatial dependences of radiation at the focus. We have characterized the high-speed spectral camera ModuPIX, which is a single Timepix device with a fast parallel readout allowing up to 850 frames per second with 256•256 pixels and a 55 [mu]m pitch defined by the frame frequency. By means of the silicon monochromator the energy response function is measured in clustering mode by the energy scan over total X-ray tube spectrum

Plasma-chemical dissociation of hydrogen sulfide

This article summarizes the existing achievements for hydrogen and elemental sulfur production by plasma-chemical dissociation of hydrogen sulfide. Because of the fact that oil and natural gas will soon end, development of environmentally clean hydrogen-based energetic is especially actual. Also possibility of obtaining the elementally pure sulfur, which is used in the wide range of industries from construction to agriculture, looks attractive. During the industrial test a reactor was designed and the parameters, that allow to proceed the hydrogen sulfide dissociation with minimal energy consumption and acceptable yields of the final products, were found