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121.
Journal of Mining Science - 相似文献
122.
A Novel Technology for Natural Gas Conversion by Means of Integrated Oxidative Coupling and Dry Reforming of Methane 下载免费PDF全文
Dr. Joris W. Thybaut Prof. Guy B. Marin Dr. Claude Mirodatos Dr. Yves Schuurman Dr. Andre C. van Veen Prof. Vladislav A. Sadykov Dr. Helmut Pennemann Dr. Rainer Bellinghausen Prof. Leslaw Mleczko 《化学,工程师,技术》2014,86(11):1855-1870
A novel process concept for the oxidative coupling of methane followed by the oligomerization to liquids has been developed within the frame of the EU integrated project OCMOL. This technology is based on process intensification principles via cutting‐edge structured microreactor technology. It is also a fully integrated industrial process through the re‐use and the recycling of by‐products, in particular CO2, at every process stage. The focus of this contribution is on the reaction engineering aspects of the core steps, i.e., catalysts, kinetics and reactor design for the methane coupling and reforming. 相似文献
123.
Anastasia V. Poznyak Vasily N. Sukhorukov Alexander Zhuravlev Nikolay A. Orekhov Vladislav Kalmykov Alexander N. Orekhov 《International journal of molecular sciences》2022,23(3)
For more than a decade, atherosclerosis has been one of the leading causes of death in developed countries. The issue of treatment and prevention of the disease is especially acute. Despite the huge amount of basic and clinical research, a significant number of gaps remain in our understanding of the pathogenesis of atherosclerosis, and only their closure will bring us closer to understanding the causes of the disease at the cellular and molecular levels and, accordingly, to the development of an effective treatment. One of the seemingly well-studied elements of atherogenesis is the mTOR signaling pathway. However, more and more new details are still being clarified. Therapeutic strategies associated with rapamycin have worked well in a number of different diseases, and there is every reason to believe that targeting components of the mTOR pathway may pay off in atherosclerosis as well. 相似文献
124.
Marie Ebeyer-Masotta Tanja Eichhorn Ren Weiss Vladislav Semak Lucia Laukov Michael B. Fischer Viktoria Weber 《International journal of molecular sciences》2022,23(3)
Inflammation and thrombosis are closely intertwined in numerous disorders, including ischemic events and sepsis, as well as coronavirus disease 2019 (COVID-19). Thrombotic complications are markers of disease severity in both sepsis and COVID-19 and are associated with multiorgan failure and increased mortality. Immunothrombosis is driven by the complement/tissue factor/neutrophil axis, as well as by activated platelets, which can trigger the release of neutrophil extracellular traps (NETs) and release further effectors of immunothrombosis, including platelet factor 4 (PF4/CXCL4) and high-mobility box 1 protein (HMGB1). Many of the central effectors of deregulated immunothrombosis, including activated platelets and platelet-derived extracellular vesicles (pEVs) expressing PF4, soluble PF4, HMGB1, histones, as well as histone-decorated NETs, are positively charged and thus bind to heparin. Here, we provide evidence that adsorbents functionalized with endpoint-attached heparin efficiently deplete activated platelets, pEVs, PF4, HMGB1 and histones/nucleosomes. We propose that this elimination of central effectors of immunothrombosis, rather than direct binding of pathogens, could be of clinical relevance for mitigating thrombotic complications in sepsis or COVID-19 using heparin-functionalized adsorbents. 相似文献
125.
Wei Li Zhen Yue Artur Lozovoi Oleg Petrov Carlos Mattea Siegfried Stapf 《Journal of Polymer Research》2018,25(11):239
The structure of chain entanglements in the solid state is important for revealing the relationship of structure and properties of polyolefin. In this work, low-field solid-state 1H NMR is used to study the chain dynamics of ultra-high molecular weight polyethylene (UHMWPE) in the solid state. It has been found that the relaxation distribution, analyzed by a multi-exponential inversion program, is an effective method to characterize the heterogeneous chain mobility. It is evidenced from the results that the UHMWPE in a less entangled state presents an obviously heterogeneous distribution of chain mobility in the non-crystalline phase, corresponding to its heterogeneous distribution of entangled points. In comparison, the commercial UHMWPE with a large number of entanglements shows a much more uniform mobility of the non-crystalline components. This heterogeneous distribution of chain mobility becomes even more critical after annealing the samples below the melting point, especially for the less entangled UHMWPE. 相似文献
126.
It is shown that the decomposition of a mixture of nitrates or coprecipitated carbonates or hydroxides of Mg and Nd form catalysts manifesting similar catalytic properties, while the catalyst obtained by impregnation is more active but much less selective. The mechanism of formation of the catalytically active phase and the nature of the active sites are discussed. 相似文献
127.
Robert C. Pullar Yong Zhang Lifeng Chen Shoufeng Yang Julian R.G. Evans Peter Kr. Petrov Andrei N. Salak Dmitry A. Kiselev Andrei L. Kholkin Victor M. Ferreira Neil McN. Alford 《Journal of the European Ceramic Society》2007,27(16):4437-4443
Applying combinatorial methods to materials science offers the opportunity to accelerate the discovery of more efficient dielectric ceramics. High-throughput methods have the potential to investigate the effects of a wide range of dopants on the dielectric properties, and to optimise existing systems, encouraging the short innovation cycles that the communications technology industry requires. The London University Search Instrument (LUSI) is a fully automated, high-throughput combinatorial robot that has the potential capability to produce large numbers of sintered bulk ceramic samples with varying composition in 1 day, as combinatorial libraries on alumina substrates. Ba1−xSrxTiO3 (BST) libraries were produced by LUSI as a proof-of-principle, with x = 0–1 in steps of 0.1, and fired to 1350 and 1400 °C for 1 h. Part I of this paper described the manufacture and physical characterisation of BST libraries, showing a regular change in composition with x across the libraries. In this second part, the dielectric properties of BST libraries produced by LUSI are assessed at frequencies between 100 Hz and 1 MHz, and at temperatures between 150 and 500 K. Local piezoelectric properties were also characterised by scanning probe microscope (SPM). All measurements showed evidence of a clear functional gradient varying with x across the library, with measured r corresponding to expected values for BST. 相似文献
128.
129.
Togobitskaya D. N. Piptyuk V. P. Petrov A. F. Grekov S. V. Mirgorodskaya A. S. 《Metallurgist》2019,62(11-12):1115-1122
Metallurgist - A procedure is developed for calculating criteria for estimation and evaluation of chemical and structural micro-inhomogeneity of ferroalloy production melts. Models are proposed for... 相似文献
130.
P. Petrov 《Zeitschrift für Jagdwissenschaft》1972,18(2):66-76
Zusammenfassung Durch Rundfrage und ergänzende Untersuchungen wurde der gegenwärtige Bestand an Auerwild im südlichen Teil des Verbreitungsgebiets der Art ermittelt. Gegenwärtig leben in Bulgarien etwa 2600 Stück in fünf Vorkommen mit Schwerpunkten in den Rhodopen (70%) und im Rilagebirge (20%). Der zahlenmäßige Rückgang und das Verschwinden an den Rändern der Vorkommensgebiete wird für die letzten 50 Jahre dargestellt. Die Ursache für den Rückgang ist in der zunehmenden Nutzung der Wälder und in der Störung durch die wirtschaftliche Tätigkeit und den Verkehr zu suchen.
Summary By means of questionnaires and supplementary studies, the present conditions of Capercaillie in the southern part of its habitat was ascertained. Currently, about 2,600 birds are living in Bulgaria in five main areas, with concentrations in the Rhodope (70%) and in the Rila Moun-
Résumé Par voie d'enquête complétée par des recherches, l'effectif actuel de l'Urogalle est établi pour la partie méridionale de l'aire d'extension de l'espèce: quelque 2600 têtes d'Urogalle sont réparties en cinq stations, principalement dans les Rhodopes (70%) et dans le Mont Rila (20%). On fait état de la régression de l'espèce en périphérie de son aire de dispersion au cours des cinquante dernières années.Les causes de cette diminution sont à rechercher dans l'exploitation de plus en plus intensive des forêts, dans l'activité économique croissante et dans le développement des voies de communication.相似文献