Correction: Unravelling potential reaction intermediates during catalytic pyrolysis of polypropylene with microscopy and spectroscopy

Correction for ‘Unravelling potential reaction intermediates during catalytic pyrolysis of polypropylene with microscopy and spectroscopy’ by Ina Vollmer et al., Catal. Sci. Technol., 2024, 14, 894–902, https://doi.org/10.1039/d3cy01473h

The Role of Social Responsibility in Big Business Practics

The study of corporate social responsibility has become especially relevant in national science in the context of the development of big business able to assume significant social responsibilities. The article focuses on the issues of the nature and specificity of social responsibility of big business in Russia. The levels of social responsibility and the arrangements for social programmes implementation are also highlighted

Geomorphology of the Central Kamchatka Depression, the Kamchatka Peninsula, NE Pacific

ABSTRACTThe Kamchatka Peninsula lies on the eastern active margin of Eurasia, adjacent to the Kuril-Kamchatka subduction zone. In this study, we provide a geomorphological map of the Central Kamchatka Depression – the largest sedimentary basin in Kamchatka and also in all the island arcs of the North Pacific. The depression extends along Kamchatka at latitudes ∼44–46° N for more than 400 km and is up to 100 km wide. The geomorphological map of the Central Kamchatka Depression is designed at a scale of 1:500,000 and contains ∼3000 mapped objects. Volcanic and tectonic landforms have been collected from published sources and generalised to the map scale. Glacial and fluvial landforms have been mapped using remote sensing data and field geomorphological surveys. Areas of ambiguous interpretation have been outlined. This map is the most detailed geomorphological map published for this region that may guide further geomorphological and paleogeographical investigations

Brands. critical and managerial perspectives

The development of probes for biomedical applications demands materials with low toxicity levels besides fluorescence or magnetic properties to be detected by confocal microscopes or MRI resonators. Several drug delivery systems or other biomedical materials prepared with hydroxyapatite have been proposed, however, toxicity effects might arise when the size of particles is nanometric. In this study, hydroxyapatite functionalized with glucuronic or folic acids presented lower oxidative stress, measured from lipoperoxides and nitric oxide indicators in rats than pure hydroxyapatite. In separated experiments, hydroxyapatite was doped with dysprosium cations by coprecipitation producing a single crystal phase with fluorescent properties easily visualized by confocal microscopy when excited at 488 nm. These particles also presented the ability to modify the proton relaxation time in T1 maps collected by magnetic resonance imaging. These modified hydroxyapatite nanoparticles could be candidates to design bimodal probes with low toxicity. © 2014 Elsevier B.V. All rights reserved

MACROMOLECULAR COMPOUNDS AND POLYMERIC MATERIALS Chemical Structure and Physicochemical Properties of Oxidized Hydrolysis Lignin

Abstract-The structure of hydrolysis lignin oxidized with hydrogen peroxide in acid medium was studied by NMR spectroscopy and by matrix-assisted laser desorption/ionization and electrospray ionization mass spectrometry. The sorption, ion-exchange, and surfactant properties of oxidized hydrolysis lignin were studied, and possible application areas of this substance were suggested

How Short is the Strongest Hydrogen Bond in the Proton-Bound Homodimers of Pyridine Derivatives?

Hydrogen bond geometries in the proton-bound homodimers of ortho-unsubstituted and ortho-methylsubstituted pyridine derivatives in aprotic polar solution were estimated using experimental NMR data. Within the series of homodimers studied the hydrogen bond lengths depend on the proton affinity of pyridines andat least for the ortho-methylsubstituted pyridineson the p<i>K</i>_a of the conjugate acids in an approximately quadratic manner. The shortest possible hydrogen bond in the homodimers of ortho-unsubstituted pyridines is characterized by the N···N distance of 2.613 Å. Steric repulsion between the methyl groups of the ortho-methylsubstituted pyridines becomes operative at an N···N distance of ∼2.7 Å and limits the closest approach to 2.665 Å

NMR Study of Solvation Effect on the Geometry of Proton-Bound Homodimers of Increasing Size

Hydrogen bond geometries in the proton-bound homodimers of quinoline and acridine derivatives in an aprotic polar solution have been experimentally studied using H-1 NMR at 120 K. The reported results show that an increase of the dielectric permittivity of the medium results in contraction of the N center dot center dot center dot N distance. The degree of contraction depends on the homodimer's size and its substituent-specific solvation features. Neither of these effects can be reproduced using conventional implicit solvent models employed in computational studies. In general, the N center dot center dot center dot N distance in the homodimers of pyridine, quinoline, and acridine derivatives decreases in the sequence gas phase > solid state > polar solvent

Reconstruction of relative sea-level changes based on a multiproxy study of isolated basins on the Onega Peninsula (White Sea, northwestern Russia)

This study presents the results of lithological, diatom, geochemical analyses and radiocarbon chronology of the bottom lake sediments and peat bogs in the central part of the Onega Peninsula (the southern coast of the White Sea): Lake Maloye Murakanskoye (11.0 m a.s.l.), Lake Zhirovskoye (9.5 m a.s.l.), Lake Murakanskoye (7 m a.s.l.), and the Gorbovatiy Mokh bog (6.5 m a.s.l.). The bottom topography and sediments of Lake Murakanskoye were examined using sonar and ground penetration radar (GPR) survey, whereas in the other locations only the water depth was measured. Then, the digital models of the lake bottom topography were created. As an additional indicator of the relative sea-level (RSL) position, we used data on the altitude of the coastal terraces. Evidences of two transgressions in the White Sea (late glacial and Middle Holocene) are revealed. The transgressions were interrupted by two regressions (Early and Late Holocene). Our studies do not allow us to make a clear conclusion about the time and maximum level of the late glacial transgression. However, we may suggest that its level was above 11 m a.s.l. The regression of the Early Holocene started before 10.6–10.2 ka cal BP when the water level in the study area dropped below the altitude of 11m. At 9.4–9.1 ka cal BP the RSL was at an altitude of ca 7m. The Middle Holocene transgression (Tapes) started after 8.4 ka cal BP. The maximum level was reached before 7.4 ka cal BP and did not exceed an altitude of 9.5 m. The RSL stabilized at an altitude about 8.5–8 m during 7.4–6.0 ka cal BP. During 6.0–3.9 ka cal BP RSL very slowly decreased or fluctuated by the level of 8–7 m. RSL began to fall from the 7 m altitude about 4.0–3.9 ka cal BP and by 2.7–2.3 ka cal BP the sea-level reached 4.5 m. After that RSL dropped to its modern position. During the last 4.0 ka cal BP the rate of RSL fall was approximately 0.17–0.18 cm/year. © 202