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Julian Zacharjasz Anna M. Mleczko Pawe Bkowski Tomasz Piontek Kamilla Bkowska-ywicka 《International journal of molecular sciences》2021,22(11)
Knee osteoarthritis (OA) is a degenerative knee joint disease that results from the breakdown of joint cartilage and underlying bone, affecting about 3.3% of the world’s population. As OA is a multifactorial disease, the underlying pathological process is closely associated with genetic changes in articular cartilage and bone. Many studies have focused on the role of small noncoding RNAs in OA and identified numbers of microRNAs that play important roles in regulating bone and cartilage homeostasis. The connection between other types of small noncoding RNAs, especially tRNA-derived fragments and knee osteoarthritis is still elusive. The observation that there is limited information about small RNAs different than miRNAs in knee OA was very surprising to us, especially given the fact that tRNA fragments are known to participate in a plethora of human diseases and a portion of them are even more abundant than miRNAs. Inspired by these findings, in this review we have summarized the possible involvement of microRNAs and tRNA-derived fragments in the pathology of knee osteoarthritis. 相似文献
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The oxidative coupling of methane (OCM) was carried out in a polytropic fixed-bed reactor applying a Zr/La/Sr catalyst developed by the Neste company. Over this catalyst the OCM reaction follows a complex reaction scheme which includes primary parallel reaction steps to CO, CO2 and C2H6 and consecutive reactions of ethane to ethylene or COx. Yield of higher hydrocarbons C2+ obtained with this catalyst strongly depended on reaction conditions, i.e. low partial pressures of methane and oxygen obtained by diluting the feed gas with nitrogen and high reaction temperatures promoted C2+ selectivity and yield. The maximum yield amounted to 21.4% (20 Vol.-% CH4, 9 Vol.-% O2, 71 Vol.-% N2, T = 860°C; XCH4 = 41.8%, S = 52.5%). This result belongs to the highest yields reported in the open literature. 相似文献
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Structured catalysts consisting of metal sheets on which Raney nickel was deposited by the thermal spraying method were tested for the liquid‐phase hydrogenation of glucose to sorbitol and 2‐nitrotoluene to 2‐methylaniline, used as model reactions. Catalytic tests performed in a bench‐scale (1 L) reactor showed that the catalytic activity of Raney Ni sheets is significantly higher than the one of the pellets used for fixed‐bed applications, but lower than the activity of the powder catalyst used in slurry mode. The activity could be significantly improved when applying a two‐phase co‐current flow through a monolith. In this case, the activity was superior to the one obtained with the slurry catalyst. These results confirm the potential of Raney Ni monoliths as structured catalysts. 相似文献
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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
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Marcin Słoma Małgorzata Jakubowska Andrzej Kolek Krzysztof Mleczko Piotr Ptak Adam Witold Stadler Zbigniew Zawiślak Anna Młożniak 《Journal of Materials Science: Materials in Electronics》2011,22(9):1321-1329
This paper presents the results of authors investigations on elaboration of a new thick film composition filled with carbon
nanotubes (CNTs). The polymer composition consists of polymer vehicle, which is the solution of organic resin in certain combination
of solvents, and functional phase—carbon nanotubes well dispersed in the vehicle. The pastes were applied with screen-printing
on several substrates and temperature cured. The properties of obtained layers were characterized. Series of samples were
prepared with different amount of CNTs to evaluate electrical properties. Changes in resistance were investigated during periodic
mechanical and temperature stresses, realized through cyclical bending and rapid temperature change. Tensometric effect was
also investigated. Investigations have proved that polymer composites based on carbon nanotubes exhibit high resilience to
stress factors. Resistance change in function of temperature was also investigated to evaluate temperature coefficient of
resistance (TCR). All this aspects are important for elastic resistors fabrication in printed electronics microcircuits. Resistance
and noise measurements in cryostats have also been involved. 1/f type noise has been observed. Noise intensity, calculated
in decade frequency bands, rises significantly with increasing temperature. Activation energies of thermally activated noise
sources (TANS) have been revealed using low-frequency noise spectroscopy. Relatively large value of negative TCR has been
obtained from resistance versus temperature curve. Calculated dimensionless sensitivity is similar to that observed in cryogenic
temperature sensors. However, bulk noise intensity of resistive layer is larger than obtained for lead containing RuO2 based resistive layers. 相似文献
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In a fluidized-bed membrane reactor the selectivity of separation can be controlled by influencing the hydrodynamics of the fluidized bed. In this reactor type, with the mass transport limitation between bubbles and the emulsion phase, even with the non-selective membranes, high selectivity of separation can be achieved. This opens the possibility for applications of membrane reactors for reaction systems for which selective membranes do not exist, e.g. when Knudsen-type membranes or form-selective separation can not be applied. This paper is aimed at explaining the interaction between the selectivity of separation and the hydrodynamics of the fluidized bed by means of simulations that were performed for a fluidized-bed membrane reactor for catalytic partial oxidation of methane. 相似文献
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K. Mleczko Z. Zawilak A.W. Stadler A. Kolek A. Dziedzic J. Cichosz 《Microelectronics Reliability》2008,48(6):881-885
Low-frequency noise spectroscopy is used to examine the interactions between resistive and conductive films that take place during thick-film resistor (TFR) fabrication. Two noise parameters are introduced to quantitatively describe the strength of these interactions. They refer to intensity and repeatability of the noise generated in the resistor interfaces. Extensive experimental studies performed on ruthenium dioxide and bismuth ruthenate TFRs terminated with gold, platinum–gold, palladium–silver and platinum–silver contacts from various manufacturers allow to establish criteria of pastes compatibility and to evaluate compatible systems of pastes for standard “on-alumina” and low-temperature co-fired ceramic (LTCC) resistors. It is found that gold contacts form low-size-effect, stable, low-noise interfaces both with ruthenium dioxide and bismuth ruthenate TFRs. Silver-containing terminations can be used with bismuth ruthenate but not with ruthenium dioxide resistors. Manufacturer optimized system of pastes for LTCC technology works best when used to produce high-resistive, co-fired devices. 相似文献
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