Механизм образования пироуглерода на поверхности технического углерода

In the article a mechanism of pyrocarbon formation on the soot surface by the decomposition of hydrocarbon gases is suggested. The mechanism involves the formation of decomposition products in the gas phase and their adsorption on the active centers of the soot. The defects of a crystal lattice formed on the contact borders of crystallites can be these active centers. Three models of pyrocarbon formation on the surface of a single soot particle and on the surface of soot structures are considered in detail. The results of mathematical calculations and experimental data are also given in the article. We explained the reason of polyextreme dependence of specific surface changing of technical carbon during the pyrocarbon formation process. Substrate influence on the pyrocarbon deposition regularities on the carbon material surface is also established. These regularities must be taken into account at the production of carbon materials if the stage of pyrocarbon formation is available.Высказана гипотеза механизма образования пироуглерода на поверхности сажи при разложении низших углеводородов в газовой фазе. Механизм предполагает возникновение в газовой фазе продуктов уплотнения, их адсорбцию на активных центрах поверхности сажи, которыми являются дефекты кристаллической решётки, возникающие на границах контактов кристаллитов, и последующую карбонизацию. Гипотеза основывается на результатах математического моде-лирования и экспериментальных данных

Влияние углеродной поверхности на закономерности образования пироуглерода

The article suggests a mechanism of pyrocarbon formation on the soot surface and explains the reason of specific surface polyextremity changing. It is possible only due to heterogeneity of pyrocarbon deposition process. It is assumed that hydrocarbon products adsorption from a gas phase takes place on the surface active centers which are formed on the boundaries of contact of crystallites and places of heteroatoms localization. Experimental results confirming these assumptions are given. It is shown that the length of the boundaries of contact of crystallites will influence the intensity change of specific surface (H-factor) and also on the rate of the chemical reactionВ статье обсуждаются экспериментальные результаты, подтверждающие предположение о взаимосвязи «дефектности» поверхности частиц технического углерода и скорости образования на них пироуглерода

Синтез углеводородов С4+ из газа электрокрекинга органического сырья

The possibility of С4+ hydrocarbon synthesis by the hydroolygomerization of acetylene contained in the gas obtained by electrocracking of organic raw materials is shown.Показана возможность синтеза углеводородов С4+ гидроолигомеризацией ацетилена, содер-жащегося в газе электрокрекинга органического сырья

МЕХАНИЗМ ОБРАЗОВАНИЯ ПИРОУГЛЕРОДА В ПРОЦЕССЕ ПИРОЛИЗА УГЛЕВОДОРОДНОГО СЫРЬЯ

Experimental results confirming the mechanism of pyrocarbon formation through the steps of high-molecular pyrolysis products forming in the gas phase are presented. Adsorption of high-molecular pyrolysis products on the active centers of the substrate localized at the boundaries of the contacts of its crystallites and their subsequent carbonization is confirmed. The decreasing in the length of the substrate crystallites contact boundaries leads to the increase in the content of high-molecular compounds in the gas and to the decrease in the hydrogen concentration is shown. The relation between the composition of the exhaust gas and the surface of the sealing material creates the prerequisites for controlling the pyro-consolidation process according the composition of the off-gas. The composition of high-molecular liquid pyrolysis products was identified. The difference in the composition of high-molecular pyrolysis products of the propane-butane fraction and the electric cracking gas was established. The influence of raw materials and pyrolysis conditions on the group composition of high-molecular pyrolysis products formed is shown.Представлены экспериментальные результаты, подтверждающие механизм образования пироуглерода через стадии возникновения в газовой фазе высокомолекулярных продуктов пиролиза, их адсорбции на активных центрах подложки, локализующихся на границах контактов ее кристаллитов, и последующей карбонизации. Показано, что сокращение протяженности границ контактов кристаллитов подложки приводит к увеличению содержания в газе высокомолекулярных соединений и снижению концентрации водорода. Взаимосвязь между составом отходящего газа и поверхностью уплотняемого материала создает предпосылки для управления процессом пироуплотнения по составу отходящего газа. Идентифицирован состав высокомолекулярных жидких продуктов пиролиза. Установлено различие в составах высокомолекулярных продуктов пиролиза пропан-бутановой фракции и газа электрокрекинга. Показано влияние сырья и условий пиролиза на групповой состав образующихся высокомолекулярных продуктов пиролиза

Bi-allelic <em>ACBD6</em> variants lead to a neurodevelopmental syndrome with progressive and complex movement disorders

\ua9 The Author(s) 2023. Published by Oxford University Press on behalf of the Guarantors of Brain. The acyl-CoA-binding domain-containing protein 6 (ACBD6) is ubiquitously expressed, plays a role in the acylation of lipids and proteins and regulates the N-myristoylation of proteins via N-myristoyltransferase enzymes (NMTs). However, its precise function in cells is still unclear, as is the consequence of ACBD6 defects on human pathophysiology. Using exome sequencing and extensive international data sharing efforts, we identified 45 affected individuals from 28 unrelated families (consanguinity 93%) with bi-allelic pathogenic, predominantly loss-of-function (18/20) variants in ACBD6. We generated zebrafish and Xenopus tropicalis acbd6 knockouts by CRISPR/Cas9 and characterized the role of ACBD6 on protein N-myristoylation with myristic acid alkyne (YnMyr) chemical proteomics in the model organisms and human cells, with the latter also being subjected further to ACBD6 peroxisomal localization studies. The affected individuals (23 males and 22 females), aged 1-50 years, typically present with a complex and progressive disease involving moderate-to-severe global developmental delay/intellectual disability (100%) with significant expressive language impairment (98%), movement disorders (97%), facial dysmorphism (95%) and mild cerebellar ataxia (85%) associated with gait impairment (94%), limb spasticity/hypertonia (76%), oculomotor (71%) and behavioural abnormalities (65%), overweight (59%), microcephaly (39%) and epilepsy (33%). The most conspicuous and common movement disorder was dystonia (94%), frequently leading to early-onset progressive postural deformities (97%), limb dystonia (55%) and cervical dystonia (31%). A jerky tremor in the upper limbs (63%), a mild head tremor (59%), parkinsonism/hypokinesia developing with advancing age (32%) and simple motor and vocal tics were among other frequent movement disorders. Midline brain malformations including corpus callosum abnormalities (70%), hypoplasia/agenesis of the anterior commissure (66%), short midbrain and small inferior cerebellar vermis (38% each) as well as hypertrophy of the clava (24%) were common neuroimaging findings. Acbd6-deficient zebrafish and Xenopus models effectively recapitulated many clinical phenotypes reported in patients including movement disorders, progressive neuromotor impairment, seizures, microcephaly, craniofacial dysmorphism and midbrain defects accompanied by developmental delay with increased mortality over time. Unlike ACBD5, ACBD6 did not show a peroxisomal localization and ACBD6-deficiency was not associated with altered peroxisomal parameters in patient fibroblasts. Significant differences in YnMyr-labelling were observed for 68 co- and 18 post-translationally N-myristoylated proteins in patient-derived fibroblasts. N-myristoylation was similarly affected in acbd6-deficient zebrafish and X. tropicalis models, including Fus, Marcks and Chchd-related proteins implicated in neurological diseases. The present study provides evidence that bi-allelic pathogenic variants in ACBD6 lead to a distinct neurodevelopmental syndrome accompanied by complex and progressive cognitive and movement disorders

Bi-allelic ACBD6 variants lead to a neurodevelopmental syndrome with progressive and complex movement disorders

This is the author accepted manuscript. The final version is available from Oxford University Press via the DOI in this recordData availability: The data that support the findings of this study are available from the corresponding author, upon reasonable request. The mass spectrometry proteomics data have been deposited to the ProteomeXchange Consortium via the PRIDE24 partner repository with the dataset identifiers PXD024957 (YnMyr chemical proteomics in human cells), PXD043676 (YnMyr chemical proteomics in zebrafish), PXD043679 (zebrafish whole proteome), PXD043677 (YnMyr chemical proteomics in X. tropicalis) and PXD043680 (X. tropicalis whole proteome).The acyl-CoA-binding domain-containing protein 6 (ACBD6) is ubiquitously expressed, plays a role in the acylation of lipids and proteins, and regulates the N-myristoylation of proteins via N-myristoyltransferase enzymes (NMTs). However, its precise function in cells is still unclear, as is the consequence of ACBD6 defects on human pathophysiology. Utilizing exome sequencing and extensive international data sharing efforts, we identified 45 affected individuals from 28 unrelated families (consanguinity 93%) with bi-allelic pathogenic, predominantly loss-of-function (18/20) variants in ACBD6. We generated zebrafish and Xenopus tropicalis acbd6 knockouts by CRISPR/Cas9 and characterized the role of ACBD6 on protein N-myristoylation with YnMyr chemical proteomics in the model organisms and human cells, with the latter also being subjected further to ACBD6 peroxisomal localization studies. The affected individuals (23 males and 22 females), with ages ranging from 1 to 50 years old, typically present with a complex and progressive disease involving moderate-to-severe global developmental delay/intellectual disability (100%) with significant expressive language impairment (98%), movement disorders (97%), facial dysmorphism (95%), and mild cerebellar ataxia (85%) associated with gait impairment (94%), limb spasticity/hypertonia (76%), oculomotor (71%) and behavioural abnormalities (65%), overweight (59%), microcephaly (39%) and epilepsy (33%). The most conspicuous and common movement disorder was dystonia (94%), frequently leading to early-onset progressive postural deformities (97%), limb dystonia (55%), and cervical dystonia (31%). A jerky tremor in the upper limbs (63%), a mild head tremor (59%), parkinsonism/hypokinesia developing with advancing age (32%), and simple motor and vocal tics were among other frequent movement disorders. Midline brain malformations including corpus callosum abnormalities (70%), hypoplasia/agenesis of the anterior commissure (66%), short midbrain and small inferior cerebellar vermis (38% each), as well as hypertrophy of the clava (24%) were common neuroimaging findings. acbd6-deficient zebrafish and Xenopus models effectively recapitulated many clinical phenotypes reported in patients including movement disorders, progressive neuromotor impairment, seizures, microcephaly, craniofacial dysmorphism, and midbrain defects accompanied by developmental delay with increased mortality over time. Unlike ACBD5, ACBD6 did not show a peroxisomal localisation and ACBD6-deficiency was not associated with altered peroxisomal parameters in patient fibroblasts. Significant differences in YnMyr-labelling were observed for 68 co- and 18 post-translationally N-myristoylated proteins in patient-derived fibroblasts. N-Myristoylation was similarly affected in acbd6-deficient zebrafish and Xenopus tropicalis models, including Fus, Marcks, and Chchd-related proteins implicated in neurological diseases. The present study provides evidence that bi-allelic pathogenic variants in ACBD6 lead to a distinct neurodevelopmental syndrome accompanied by complex and progressive cognitive and movement disorders

Mechanism of pyrocarbon formation on the soot surface

In the article a mechanism of pyrocarbon formation on the soot surface by the decomposition of hydrocarbon gases is suggested. The mechanism involves the formation of decomposition products in the gas phase and their adsorption on the active centers of the soot. The defects of a crystal lattice formed on the contact borders of crystallites can be these active centers. Three models of pyrocarbon formation on the surface of a single soot particle and on the surface of soot structures are considered in detail. The results of mathematical calculations and experimental data are also given in the article. We explained the reason of polyextreme dependence of specific surface changing of technical carbon during the pyrocarbon formation process. Substrate influence on the pyrocarbon deposition regularities on the carbon material surface is also established. These regularities must be taken into account at the production of carbon materials if the stage of pyrocarbon formation is available

Сarbon surface influence on the pyrocarbon formation regularities

The article suggests a mechanism of pyrocarbon formation on the soot surface and explains the reason of specific surface polyextremity changing. It is possible only due to heterogeneity of pyrocarbon deposition process. It is assumed that hydrocarbon products adsorption from a gas phase takes place on the surface active centers which are formed on the boundaries of contact of crystallites and places of heteroatoms localization. Experimental results confirming these assumptions are given. It is shown that the length of the boundaries of contact of crystallites will influence the intensity change of specific surface (H-factor) and also on the rate of the chemical reactio

Synthesis of С₄₊ hydrocarbons from organic raw materials electro-cracking gas

The possibility of С4+ hydrocarbon synthesis by the hydroolygomerization of acetylene contained in the gas obtained by electrocracking of organic raw materials is shown

THE PYROCARBON FORMATION MECHANISM DURING THE HYDROCARBON PYROLYSIS PROCESS

Experimental results confirming the mechanism of pyrocarbon formation through the steps of high-molecular pyrolysis products forming in the gas phase are presented. Adsorption of high-molecular pyrolysis products on the active centers of the substrate localized at the boundaries of the contacts of its crystallites and their subsequent carbonization is confirmed. The decreasing in the length of the substrate crystallites contact boundaries leads to the increase in the content of high-molecular compounds in the gas and to the decrease in the hydrogen concentration is shown. The relation between the composition of the exhaust gas and the surface of the sealing material creates the prerequisites for controlling the pyro-consolidation process according the composition of the off-gas. The composition of high-molecular liquid pyrolysis products was identified. The difference in the composition of high-molecular pyrolysis products of the propane-butane fraction and the electric cracking gas was established. The influence of raw materials and pyrolysis conditions on the group composition of high-molecular pyrolysis products formed is shown