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981.
Jiina Hofmanov Josef Slavík Miroslav Ciganek Petra Ovesn Zuzana Tylichov Martina Karasov Ondej Zapletal Nicol Strakov Jiina Prochzkov Jan Bouchal Zdenk Kol Jií Ehrmann Monika Levkov Zlatka Hukov Pavel Skalický Alois Kozubík Miroslav Machala Jan Vondr
ek 《International journal of molecular sciences》2021,22(13)
982.
Dávid Medved' Michal Ivor Alexandra Kovalčíková Erika Múdra Tamás Csanádi Richard Sedlák Hakan Ünsal Peter Tatarko Monika Tatarková Pavol Šajgalík Ján Dusza 《International Journal of Applied Ceramic Technology》2023,20(1):224-235
Wear characteristics of an (Mo–Nb–Ta–V–W)C high-entropy carbide were investigated using ball-on-flat technique. The experimental material with a high relative density of 99.0%, single phase, average grain diameter of 10.7 μm, and nanohardness of grains 28.6 GPa was prepared by ball-milling and two-step field-assisted sintering. The tribological test was realized during dry sliding in air with the SiC ball as tribological partner at applied loads 5, 25, and 50 N. The microstructure, deformation, and damage characteristics were studied using scanning electron microscopy and confocal electron microscopy. The friction coefficient values during the test with 5 and 25 N were very similar and stable, with a value of approximately .4, whereas during the test with 50 N, it decreased from the value of .48–.42. The specific wear rate increased with increasing load from 3.71 × 10–7 mm3/N m at 5 N to 2.59 × 10–6 mm3/N m at 50 N. The dominant wear mechanism was mechanical wear with intensive grains pullout, fracture, and powder formation, without visible tribochemical reactions and tribo-layer formation. The wear rate decreased due to the created rolling contacts among the tribopartners thanks to the hard and spherical nanopowders present. 相似文献
983.
Ewa Janiszewska Stanisław Kowalak Monika Gierczyńska Violetta Dolata Michał Zieliński Maria Wojciechowska 《Catalysis Letters》2006,112(1-2):97-103
The metallosilicalites (MFI) containing copper ([Cu,Si]), zinc ([Zn,Si]) or both elements ([Cu,Zn,Si]) were prepared and modified
as potential catalysts for the NO reduction with propene. The H-[Cu,Si] samples showed the highest activity, which was initially
comparable to that of Cu-ZSM-5, but contrary to the latter, it increased with time. The framework Cu or Cu released from the
framework probably act as active sites. 相似文献
984.
Fruhmann Berger Monika; Johannsen Leif; Karnath Hans-Otto 《Canadian Metallurgical Quarterly》2008,22(6):697
Spatial neglect is characterized by a deviation of the eyes and the head during active search, as well as at rest. Here the authors investigate the hitherto unknown relationship between these striking behaviors in the course of recovery. Gaze, eye-in-head, and head-on-trunk positions were recorded separately under two experimental conditions: (i) at rest (i.e., without any specific requirements, doing nothing) and (ii) during active exploratory search in a large visual array of 240° × 80° over a 10-month period. The authors observed a parallel decrease of eye and head (= gaze) deviation in both conditions, accompanied by a comparable decline in neglect severity. The results strengthen the view that the marked gaze deviation toward the ipsilesional side in patients with spatial neglect is due to a very elementary disturbance of human spatial information processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
985.
Maesschalck Sophie De Colle Didier Lievens Ilse Pickavet Mario Demeester Piet Mauz Christian Jaeger Monika Inkret Robert Mikac Branko Derkacz Jan 《Photonic Network Communications》2003,5(3):203-225
The traffic to be carried by today's European backbone networks increases very rapidly. An important portion of this traffic consists of data traffic (mainly IP-related). In the future data traffic is expected to become the abundantly dominant traffic type, while voice traffic will only account for a very small portion of the total traffic volume. In this paper, some network topologies for such a pan-European fiber-optic backbone network are presented (more details can be found in [1]). These topologies are compared in terms of the efficiency of the network design both from a cost and capacity point of view and in terms of the availability of the connections routed over this network. In order to be able to assess the network topologies under realistic circumstances, the expected traffic demand is forecasted. This enables to make the comparison for the current traffic volume as well as for the traffic patterns of the future. As not all types of (data) traffic require the same degree of survivability and in order to leverage the total capacity cost of the network design, a distinction is made between different recovery options in the optical layer for the different traffic types considered. 相似文献
986.
Monika Karaś 《International Journal of Food Science & Technology》2019,54(5):1486-1496
Food-derived bioactive peptides can be released during digestion and have a potentially beneficial effect on human health. It is known that the penetration of peptides across the small intestine can take place in several ways. The research related to the bioavailability of peptides develops dynamically, but still raises many doubts. Since there are many barriers to absorption of peptides, there is still a need to carry out in vitro and in vivo investigations on the bioavailability of these compounds. Moreover, there are few in vivo studies regarding the absorption and activity of peptides in organs, hence the lack of unequivocal and reliable information about this process. Therefore, this review discusses the current research on in vitro and in vivo absorption of these compounds and factors that play a key role in this process and provides better understanding of the in vitro and in vivo bioavailability and bioaccessibility of peptides. 相似文献
987.
Anuj Kumar Shiva Kumar Monika Mudgel H. Kishan V. P. S. Awana 《Journal of Superconductivity and Novel Magnetism》2008,21(4):259-264
We report synthesis and magnetic characterization of variously processed magneto-superconducting (Rutheno-cuprates) RuSr2Eu1.5Ce0.5Cu2O10−δ
. The compound crystallizes in I4/mmm tetragonal structure. Magnetization measurements showed bulk magnetic ordering and superconductivity
at around 100 K and 30 K, respectively. Further, the careful examination of the low field magnetic susceptibility reveals
two minor magnetic transitions at around 135 K and 200 K, in addition to the major transition at 100 K. When the samples are
processed in different environments of air, O2 and slightly pressurized O2, the nature of magnetic transitions and the superconductivity changes dramatically. The highest superconducting transition
is achieved for the high pressure O2 annealed samples and the lowest for the air annealed one. On the other hand, the minor magnetic transitions are more prominent
in air-annealed samples. Though the minor magnetic transitions are intrinsic to all variously processed samples, they are
not clearly seen for higher O2 content samples. Basically, the Ru spins order antiferro magnetically at around 200 K (first minor transition), and reorients
themselves at 125 K (second minor transition) before finally ordering in canted ferromagnetic state or a spin glass structure.
These results can be explained on the basis of fluctuating valance of Ru4+/Ru5+.
相似文献
988.
Agnieszka Wrblewska Monika Rzepkowska Eugeniusz Milchert 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2004,79(4):343-353
The influence of the technological parameters on the epoxidation of allyl alcohol by a 30 wt% hydrogen peroxide in the medium of methanol over the Ti–BETA catalyst in the direction of glycidol has been presented. The experimental conditions were established on the basis of preliminary experiments and through the applications of statistical experimental design methods (rotatable uniform design). The results of the particular experiments were described by the following functions: the yield of glycidol in relation to allyl alcohol introduced into the reactor, the selectivity of transformation to glycidol in relation to allyl alcohol and hydrogen peroxide reacted, and the degree of conversion of allyl alcohol and H2O2. The optimal values of each function were established. The courses of functions corresponding to the parameters were plotted in the system of two variable parameters. The optimum parameters of the epoxidation process were established after the analysis of the layer drawings. The obtained results were confirmed by a series of verifying syntheses. Copyright © 2004 Society of Chemical Industry 相似文献
989.
Hart Daniel; Keller Monika; Edelstein Wolfgang; Hofmann Volker 《Canadian Metallurgical Quarterly》1998,74(5):1278
The relation of childhood personality to the development of friendship understanding and moral judgment in adolescence was considered in a longitudinal study. Personality at age 7, assessed with the California Child Q-Set, was characterized in terms of ego-resiliency and ego-control. IQ and social class were also measured. Friendship understanding was assessed when the participants were ages 7, 9, 12, 15, and 19, and moral judgment was elicited when the participants were 12, 15, and 19. Ego-resiliency was found to predict social–cognitive development in adolescence, even after the effects of IQ and childhood measures of social–cognitive development were controlled for. Analyses indicate that the effects of ego-resiliency on social–cognitive development are largely unmediated by the ability to focus attention or by social participation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
990.
Efrat Rabinovich Monika Bajorek Michael Glickman Shoshana Bar-Nun 《Israel journal of chemistry》2006,46(2):219-224
The 26S proteasome eliminates multiubiquitinated proteins in cytosol and nucleus, and from the secretory pathway by a mechanism known as ER-associated degradation (ERAD). Access to the proteasomal 20S catalytic core particle is hindered by conserved N-terminal tails of α-subunits that form a gated pore into the central channel. Hence, the isolated 20S core particle possesses slower peptide hydrolysis rates and cannot degrade multiubiquitinated proteins. Purified catalytic particles from an α3α7ΔN open channel double mutant, in which the N-terminal tails of α-subunits from opposite sites of the α ring are deleted, showed significantly enhanced peptidase activity and proteolytic properties. Here we show that also in vivo the access of substrates to the proteasomal catalytic chamber partially limits the overall rate of protein elimination. This regulation applies to unstable cytosolic proteins of the N-end rule and ubiquitin fusion degradation (UFD) pathways, as well as to ERAD substrates that must dislocate from the ER back to the cytosol in order to become ubiquitinated and degraded by the proteasome. Hence, even for a complicated multistep process such as ERAD, traffic through the proteasome itself is partially rate limiting for the entire proteolytic process. However, proteasome gating can be added to a growing list of phenomena that distinguish membrane ERAD substrates from lumenal ones because while gating hinders access of lumenal substrates, it is less effective in controlling the entry of membrane substrates. The open channel mutant is a new class of proteasome mutant, which is unrelated to the catalytic protease active sites or to the “classical” regulatory particle mutants. Its improved performance at high temperatures is in stark contrast to the behavior of the “classical” mutants, suggesting that the α3α7ΔN mutant adapts better to mild stress conditions. 相似文献