Закономерности превращения метанола в присутствии катализаторов на основе углеродных носителей

Methanol transformation in the presence of catalysts based on various carbon materials - nanofibres synthesized in the presence of Co-, Ni- and Fe-catalysts and of the carbon-carbon composite material Sibunit were studied. It was shown that the conditions of the synthesis of carbon nanofibres influence their structure and catalytical properties. A research of Cu-containing systems based on carbon nanofibers was carried out. It was found that a particle of the catalyst metal applied to the synthesis of carbon nanofibres actively participates in the interaction with methanol. Copper and cobalt promote the decomposition of methanol giving synthesis gas. Copper and ferrum show synergism in the reaction of dehydration of methyl alcohol.Изучены закономерности превращения метанола в присутствии катализаторов на основе различных углеродных материалов - нановолокон, синтезированных в присутствии кобальт-, никель- и железосодержащих катализаторов, и углерод-углеродного композиционного материала сибунит. Показано, что условия синтеза углеродных нановолокон оказывают влияние на их структуру и каталитические свойства. Проведено исследование каталитических свойств медьсодержащих систем на основе углеродных нановолокон. Установлено, что частица металла катализатора, примененного для синтеза углеродного нановолокна, активно участвует во взаимодействии с метанолом. Показано, что медь и кобальт способствуют протеканию реакции разложения метанола на синтез-газ. Медь и железо проявляют синергизм в реакции дегидрирования метилового спирта

ДЕГИДРИРОВАНИЕ ЭТАНОЛА В АЦЕТАЛЬДЕГИД В ПРИСУТСТВИИ МЕДНЫХ НАНЕСЕННЫХ КАТАЛИЗАТОРОВ НА ОСНОВЕ УГЛЕРОДНЫХ МАТЕРИАЛОВ

The process of ethanol dehydrogenation to acetaldehyde upon different copper supported on carbon catalysts has been studied. Different carbon materials – activated carbon Norit, carbon-carbon composite sibunit and activated carbon fibers (ACF) – were used as a support for the catalyst. The BET surface area as well as the porous structure of the materials were determined with the use of N2 adsorption-desorption technique. The catalysts prepared by wetness impregnation contained 5% of Cu. The effect of the carrier texture on the distribution of active metal has been shown using scanning electron microscopy. Copper deposited on ACF was well distributed in comparison with the other supports studied and had an average particle size of 20 nm. This led to higher activity of the 5% Cu/ACF catalyst. Besides, it appeared more selective in the process of dehydrogenation.Исследован процесс дегидрирования этилового спирта в присутствии медьсодержащих каталитических систем на основе различных углеродных материалов. Показано влияние структуры носителя на распределение активного компонента

Влияние предварительного окисления углеродного носителя на активность нанесенного медьсодержащего катализатора дегидрирования этанола

Copper supported catalysts based on preliminary oxidized carbon fibers have been studied. Nitric acid and hydrogen peroxide have been used for prior oxidation treatment of the supports. To characterize this materials N<sub>2</sub> adsorption-desorption and titration technics were used. Compared to nonoxidized activated carbon fibers, no significant changes in the texture of the modified supports were found, while there were differences in surface functionalities. Cupper supported catalysts were prepared by wetness impregnation and characterized by TPR, SEM. The influence of different surface functional groups on the distribution of active metal has been discussed. Besides, the catalysts were tested in the process of ethanol dehydrogenation. Cupper supported on activated carbon fibers preliminary oxidized with HNO<sub>3</sub> appeared to be more active in the process, although less stable at high temperatures. The reasons of the loss of activity have been also discussed.Исследованы медные катализаторы на основе активированных углеродных волокон, при-меняемые в процессе дегидрирования этанола. Показано влияние предварительной окислительной обработки (азотной кислотой или перекисью водорода) носителя на свойства каталитических систем

The OpenMolcas Web: A Community-Driven Approach to Advancing Computational Chemistry

The developments of the open-source OpenMolcas chemistry software environment since spring 2020 are described, with a focus on novel functionalities accessible in the stable branch of the package or via interfaces with other packages. These developments span a wide range of topics in computational chemistry and are presented in thematic sections: electronic structure theory, electronic spectroscopy simulations, analytic gradients and molecular structure optimizations, ab initio molecular dynamics, and other new features. This report offers an overview of the chemical phenomena and processes OpenMolcas can address, while showing that OpenMolcas is an attractive platform for state-of-the-art atomistic computer simulations

Cause of Death and Predictors of All-Cause Mortality in Anticoagulated Patients With Nonvalvular Atrial Fibrillation : Data From ROCKET AF

M. Kaste on työryhmän ROCKET AF Steering Comm jäsen.Background-Atrial fibrillation is associated with higher mortality. Identification of causes of death and contemporary risk factors for all-cause mortality may guide interventions. Methods and Results-In the Rivaroxaban Once Daily Oral Direct Factor Xa Inhibition Compared with Vitamin K Antagonism for Prevention of Stroke and Embolism Trial in Atrial Fibrillation (ROCKET AF) study, patients with nonvalvular atrial fibrillation were randomized to rivaroxaban or dose-adjusted warfarin. Cox proportional hazards regression with backward elimination identified factors at randomization that were independently associated with all-cause mortality in the 14 171 participants in the intention-to-treat population. The median age was 73 years, and the mean CHADS(2) score was 3.5. Over 1.9 years of median follow-up, 1214 (8.6%) patients died. Kaplan-Meier mortality rates were 4.2% at 1 year and 8.9% at 2 years. The majority of classified deaths (1081) were cardiovascular (72%), whereas only 6% were nonhemorrhagic stroke or systemic embolism. No significant difference in all-cause mortality was observed between the rivaroxaban and warfarin arms (P=0.15). Heart failure (hazard ratio 1.51, 95% CI 1.33-1.70, P= 75 years (hazard ratio 1.69, 95% CI 1.51-1.90, P Conclusions-In a large population of patients anticoagulated for nonvalvular atrial fibrillation, approximate to 7 in 10 deaths were cardiovascular, whereasPeer reviewe

Improved functionalization of oleic acid-coated iron oxide nanoparticles for biomedical applications

Superparamagnetic iron oxide nanoparticles can providemultiple benefits for biomedical applications in aqueous environments such asmagnetic separation or magnetic resonance imaging. To increase the colloidal stability and allow subsequent reactions, the introduction of hydrophilic functional groups onto the particles’ surface is essential. During this process, the original coating is exchanged by preferably covalently bonded ligands such as trialkoxysilanes. The duration of the silane exchange reaction, which commonly takes more than 24 h, is an important drawback for this approach. In this paper, we present a novel method, which introduces ultrasonication as an energy source to dramatically accelerate this process, resulting in high-quality waterdispersible nanoparticles around 10 nmin size. To prove the generic character, different functional groups were introduced on the surface including polyethylene glycol chains, carboxylic acid, amine, and thiol groups. Their colloidal stability in various aqueous buffer solutions as well as human plasma and serum was investigated to allow implementation in biomedical and sensing applications.status: publishe

The OpenMolcas Web: A Community-Driven Approach to Advancing Computational Chemistry

The developments of the open-source OpenMolcas chemistry software environment since spring 2020 are described, with a focus on novel functionalities accessible in the stable branch of the package or via interfaces with other packages. These developments span a wide range of topics in computational chemistry and are presented in thematic sections: electronic structure theory, electronic spectroscopy simulations, analytic gradients and molecular structure optimizations, ab initio molecular dynamics, and other new features. This report offers an overview of the chemical phenomena and processes OpenMolcas can address, while showing that OpenMolcas is an attractive platform for state-of-the-art atomistic computer simulations

Effects of alirocumab on types of myocardial infarction: insights from the ODYSSEY OUTCOMES trial

Aims  The third Universal Definition of Myocardial Infarction (MI) Task Force classified MIs into five types: Type 1, spontaneous; Type 2, related to oxygen supply/demand imbalance; Type 3, fatal without ascertainment of cardiac biomarkers; Type 4, related to percutaneous coronary intervention; and Type 5, related to coronary artery bypass surgery. Low-density lipoprotein cholesterol (LDL-C) reduction with statins and proprotein convertase subtilisin–kexin Type 9 (PCSK9) inhibitors reduces risk of MI, but less is known about effects on types of MI. ODYSSEY OUTCOMES compared the PCSK9 inhibitor alirocumab with placebo in 18 924 patients with recent acute coronary syndrome (ACS) and elevated LDL-C (≥1.8 mmol/L) despite intensive statin therapy. In a pre-specified analysis, we assessed the effects of alirocumab on types of MI. Methods and results  Median follow-up was 2.8 years. Myocardial infarction types were prospectively adjudicated and classified. Of 1860 total MIs, 1223 (65.8%) were adjudicated as Type 1, 386 (20.8%) as Type 2, and 244 (13.1%) as Type 4. Few events were Type 3 (n = 2) or Type 5 (n = 5). Alirocumab reduced first MIs [hazard ratio (HR) 0.85, 95% confidence interval (CI) 0.77–0.95; P = 0.003], with reductions in both Type 1 (HR 0.87, 95% CI 0.77–0.99; P = 0.032) and Type 2 (0.77, 0.61–0.97; P = 0.025), but not Type 4 MI. Conclusion  After ACS, alirocumab added to intensive statin therapy favourably impacted on Type 1 and 2 MIs. The data indicate for the first time that a lipid-lowering therapy can attenuate the risk of Type 2 MI. Low-density lipoprotein cholesterol reduction below levels achievable with statins is an effective preventive strategy for both MI types.For complete list of authors see http://dx.doi.org/10.1093/eurheartj/ehz299</p