Сорбція наночастинок при осадженні шарів

Статтю присвячено вивченню процесу самоорганізації шару поліанілінових наночастинок при гетерокоагуляції на поліамідних волокнах. Показано, що розподіл за розмірами дисперсії поліаніліну, одержаної окиснювальною конденсацією аніліну, є нормальним з максимумом при 150 нм. Встановлено, що опір багатошарових волоконних матеріалів з поліаніліновим покриттям, одержаним методом layer-by-layer, залежить від кількості шарів і типу ПАР. Процес гетерокоагуляції поліанілінових частинок на поліамідних волокнах описано за допомогою квазіхімічної моделі реакції. Показано, що в цих умовах виникають структури з обмеженою тривалістю існування і з подальшою самоорганізацією.The article is dedicated to the study of self-organization processes of conductive layer of polyaniline nanoparticles in heterocoagulation on polyamide fiber. It is shown that the particle size distribution of polyaniline dispersion obtained by the oxidative condensation of aniline is normal with a maximum of 150 nm. It is found out that the resistance of the multilayer fibrous material with a polyaniline coating obtained layer-by-layer depends on the number of layers and the type of the surfactants. The process of heterocoagulation of polyaniline particles on the polyamide fiber is described by the quasi-chemical reaction model. It has been shown that in these conditions, the structures with a limited lifetime and with following self-organization emerge

Ecological aspects of dyeing on a geterokoagulyation mechanism

Запропоновано нову технологію гетерокоагуляційного фарбування, яка базується на засадах «зеленої хімії», і призводить до суттєвого зменшення викидів токсичних речовин, економії обсягів води та енергоресурсів, покращення умов праці.Technology of the geterokoagulyation of dyeing is based on principles of «green chemistry». Results in the substantial diminishing of consumption of water, power expenses, improvements condition of labour of working personnel.Предложено новую технологию гетерокоагуляционного крашения, которая основана на принципах «зеленой химии», и приводит к существенному уменьшению выбросов токсических веществ, экономии воды и затрат энергоносителей, улучшению условий труда

Guidance for Planning and Hosting a Successful Hybrid Event - Reflections from the ACCESS Annual Assembly 2022

This is the final version.Economic and Social Research Council (ESRC

Estimation of the global amount of submarine gas hydrates formed via microbial methane formation based on numerical reaction-transport modeling and a novel parameterization of Holocene sedimentation

This study provides new estimates for the global offshore methane hydrate inventory formed due to microbial CH4 production under Quaternary and Holocene boundary conditions. A multi-1D model for particular organic carbon (POC) degradation, gas hydrate formation and dissolution is presented. The novel reaction-transport model contains an open three-phase system of two solid compounds (organic carbon, gas hydrates), three dissolved species (methane, sulfates, inorganic carbon) and one gaseous phase (free methane). The model computes time-resolved concentration profiles for all compounds by accounting for chemical reactions as well as diffusive and advective transport processes. The reaction module builds upon a new kinetic model of POC degradation which considers a down-core decrease in reactivity of organic matter. Various chemical reactions such as organic carbon decay, anaerobic oxidation of methane, methanogenesis, and sulfate reduction are resolved using appropriate kinetic rate laws and constants. Gas hydrates and free gas form if the concentration of dissolved methane exceeds the pressure, temperature, and salinity-dependent solubility limits of hydrates and/or free gas, with a rate given by kinetic parameters. Global input grids have been compiled from a variety of oceanographic, geological and geophysical data sets including a new parameterization of sedimentation rates in terms of water depth. We find prominent gas hydrate provinces offshore Central America where sediments are rich in organic carbon and in the Arctic Ocean where low bottom water temperatures stabilize methane hydrates. The world’s total gas hydrate inventory is estimated at 0.82 x 10sup13 m3 - 2.10 x 10sup15 m3 CH4 (at STP conditions) or, equivalently, 4.18–995 Gt of methane carbon. The first value refers to present day conditions estimated using the relatively low Holocene sedimentation rates; the second value corresponds to a scenario of higher Quaternary sedimentation rates along continental margins. Our results clearly show that in-situ POC degradation is at present not an efficient hydrate forming process. Significant hydrate deposits in marine settings are more likely to have formed at times of higher sedimentation during the Quaternary or as a consequence of upward fluid transport at continental margins

CASCADE-The Circum-Arctic Sediment CArbon DatabasE

Biogeochemical cycling in the semi-enclosed Arctic Ocean is strongly influenced by land–ocean transport of carbon and other elements and is vulnerable to environmental and climate changes. Sediments of the Arctic Ocean are an important part of biogeochemical cycling in the Arctic and provide the opportunity to study present and historical input and the fate of organic matter (e.g., through permafrost thawing). Comprehensive sedimentary records are required to compare differences between the Arctic regions and to study Arctic biogeochemical budgets. To this end, the Circum-Arctic Sediment CArbon DatabasE (CASCADE) was established to curate data primarily on concentrations of organic carbon (OC) and OC isotopes (δ13C, Δ14C) yet also on total N (TN) as well as terrigenous biomarkers and other sediment geochemical and physical properties. This new database builds on the published literature and earlier unpublished records through an extensive international community collaboration. This paper describes the establishment, structure and current status of CASCADE. The first public version includes OC concentrations in surface sediments at 4244 oceanographic stations including 2317 with TN concentrations, 1555 with δ13C-OC values and 268 with Δ14C-OC values and 653 records with quantified terrigenous biomarkers (high-molecular-weight n-alkanes, n-alkanoic acids and lignin phenols). CASCADE also includes data from 326 sediment cores, retrieved by shallow box or multi-coring, deep gravity/piston coring, or sea-bottom drilling. The comprehensive dataset reveals large-scale features of both OC content and OC sources between the shelf sea recipients. This offers insight into release of pre-aged terrigenous OC to the East Siberian Arctic shelf and younger terrigenous OC to the Kara Sea. Circum-Arctic sediments thereby reveal patterns of terrestrial OC remobilization and provide clues about thawing of permafrost. CASCADE enables synoptic analysis of OC in Arctic Ocean sediments and facilitates a wide array of future empirical and modeling studies of the Arctic carbon cycle. The database is openly and freely available online (https://doi.org/10.17043/cascade; Martens et al., 2021), is provided in various machine-readable data formats (data tables, GIS shapefile, GIS raster), and also provides ways for contributing data for future CASCADE versions. We will continuously update CASCADE with newly published and contributed data over the foreseeable future as part of the database management of the Bolin Centre for Climate Research at Stockholm University

(Table 1) Composition of organic matter in bottom sediments from the Kuril-Kamchatka Trench

From results of analyses of sediment samples collected on a profile crossing the Kuril-Kamchatka Trench distribution of organic D, N. carbohydrates, lipids and humic substances was established, as well as nature of their relationship with amorphous silica and clay fraction. Sum of the main biochemical groups of organic matter in the surface layer of sediments (0-1 cm) from the Kuril-Kamchatka Trench amounts to about 15%; neogenetic forms not encountered in living organisms make up 85% of organic matter. Among such forms 26% comprise humic substances formed during initial stages of polymerization of decomposition products of biochemical macromolecules

Organic matter in bottom sediments of the Northeast Pacific

The book is devoted to study of diagenetic changes of organic matter and mineral part of sediments and interstitial waters of the Pacific Ocean due to physical-chemical and microbiological processes. Microbiological studies deal with different groups of bacteria. Regularities of quantitative distribution and the role of microorganisms in geochemical processes are under consideration. Geochemical studies highlight redox processes of the early stages of sediment diagenesis, alterations of interstitial waters, regularities of variations in chemical composition of iron-manganese nodules