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31.
Mieczyslaw Korzynski Tomasz Zarski Katarzyna Korzynska 《Journal of Materials Processing Technology》2011,211(12):1982-1988
The present work compares the states of the surface textures and the oscillatory fatigue strengths of specimens made of an AZ91 alloy after turning and dynamic bearing ball peening. It was found that the specimens ball peened at different time have similar surface geometric structure parameters but different strengthening intensity. It was shown that fatigue strength follows greater peening intensity and random and isotropic surface. It was also ascertained that improving (by peening) the condition of the surface layer means enhancing fatigue strength by 20–87% compared with turning. 相似文献
32.
Physicochemical quality and oxidative stability of linseed (Linum usitatissimum) and camelina (Camelina sativa) cold‐pressed oils from retail outlets 下载免费PDF全文
33.
Daniela M. Ushizima Hrishikesh A. Bale E. Wes Bethel Peter Ercius Brett A. Helms Harinarayan Krishnan Lea T. Grinberg Maciej Haranczyk Alastair A. Macdowell Katarzyna Odziomek Dilworth Y. Parkinson Talita Perciano Robert O. Ritchie Chao Yang 《JOM Journal of the Minerals, Metals and Materials Society》2016,68(11):2963-2972
34.
Katarzyna Grzybowska Zaneta Wojnarowska Andrzej Grzybowski Marian Paluch Juan M. Giussi M. Susana Cortizo Iwona Blaszczyk-Lezak Carmen Mijangos 《Polymer》2014
In this paper, dielectric and calorimetric studies of the small-molecule glass former allyl acetoacetate monomers as well as its newly synthetized homopolymer and copolymers with different styrene composition were performed in both the liquid and glassy states. The molecular dynamics studies by the broadband dielectric spectroscopy and the stochastic temperature modulated differential scanning calorimetry enabled us to explore relaxation processes of examined materials in the wide frequency range. We found that the copolymers reveal two co-existing glass transitions characterized by the glass transition temperatures, which are very close to those of the corresponding homopolymers. These results suggest that the copolymers exhibited some sequences of acetoacetate units with a microphase-separated morphology in agreement with the value of reactivity ratio previously determined. We investigated effects of copolymerization compositions on the glass transition temperature, the isobaric fragility index, the dielectric and calorimetric intensity, and the dynamic heterogeneity on the glass transitions of the materials. 相似文献
35.
Katarzyna Lechowska ukasz Wojtyla Muriel Quinet Szymon Kubala Stanley Lutts Magorzata Garnczarska 《International journal of molecular sciences》2022,23(1)
Currently, seed priming is reported as an efficient and low-cost approach to increase crop yield, which could not only promote seed germination and improve plant growth state but also increase abiotic stress tolerance. Salinity represents one of the most significant abiotic stresses that alters multiple processes in plants. The accumulation of polyamines (PAs) in response to salt stress is one of the most remarkable plant metabolic responses. This paper examined the effect of osmopriming on endogenous polyamine metabolism at the germination and early seedling development of Brassica napus in relation to salinity tolerance. Free, conjugated and bound polyamines were analyzed, and changes in their accumulation were discussed with literature data. The most remarkable differences between the corresponding osmoprimed and unprimed seeds were visible in the free (spermine) and conjugated (putrescine, spermidine) fractions. The arginine decarboxylase pathway seems to be responsible for the accumulation of PAs in primed seeds. The obvious impact of seed priming on tyramine accumulation was also demonstrated. Moreover, the level of ethylene increased considerably in seedlings issued from primed seeds exposed to salt stress. It can be concluded that the polyamines are involved in creating the beneficial effect of osmopriming on germination and early growth of Brassica napus seedlings under saline conditions through moderate changes in their biosynthesis and accumulation. 相似文献
36.
Wanda ankowska-Jasiska Katarzyna Ostrowska 《Advanced Synthesis \u0026amp; Catalysis》1991,333(4):619-624
3-Benzoyl-2,4,5-pyrrolidinetrione ( 1a , b ) with aliphatic diamines, phenylhydrazine, semicarbazide, and guanidine derivatives yields mono and binary salts ( 4 , 7 , 10 , 11 - 14 ), enamines ( 2 , 3 ), imine ( 5 ), pyrrolo[3,4-c]pyrazole ( 6 ) and pyrrolo [3,4-e][1,4]diazepine ( 8 ), respectively. The influence of the reagents basicity on the route of cyclocondensation is studied. 相似文献
37.
Anna Z. Szeremeta Sebastian Pawlus Andrzej Nowok Katarzyna Grzybowska Maciej Zubko Andrzej Molak 《Journal of the American Ceramic Society》2020,103(6):3732-3738
Electrical impedance of bismuth manganite ceramics was studied under ambient and high hydrostatic pressure. Local disorder of crystal lattice was confirmed using XRD and DSC. Two relaxation processes were discerned. One was attributed to small polarons, which showed a changeover from variable range hopping features related to Fermi glass and structural disorder to the nearest neighbor hopping behavior in higher temperature range related to uniform distribution of energy levels. Hydrostatic pressure shortened relaxation times that would be interesting for applications. The second process, which was assigned to the nearest neighbor hopping of polarons, also exhibited a changeover to glassy features in a high-temperature range. 相似文献
38.
Anna Kloska Grzegorz M. Cech Dariusz Nowicki Monika Macig-Dorszyska Aleksandra E. Bogucka Stephanie Markert Drte Becher Katarzyna Potrykus Paulina Czaplewska Agnieszka Szalewska-Paasz 《International journal of molecular sciences》2022,23(2)
Osmotic changes are common challenges for marine microorganisms. Bacteria have developed numerous ways of dealing with this stress, including reprogramming of global cellular processes. However, specific molecular adaptation mechanisms to osmotic stress have mainly been investigated in terrestrial model bacteria. In this work, we aimed to elucidate the basis of adjustment to prolonged salinity challenges at the proteome level in marine bacteria. The objects of our studies were three representatives of bacteria inhabiting various marine environments, Shewanella baltica, Vibrio harveyi and Aliivibrio fischeri. The proteomic studies were performed with bacteria cultivated in increased and decreased salinity, followed by proteolytic digestion of samples which were then subjected to liquid chromatography with tandem mass spectrometry analysis. We show that bacteria adjust at all levels of their biological processes, from DNA topology through gene expression regulation and proteasome assembly, to transport and cellular metabolism. The finding that many similar adaptation strategies were observed for both low- and high-salinity conditions is particularly striking. The results show that adaptation to salinity challenge involves the accumulation of DNA-binding proteins and increased polyamine uptake. We hypothesize that their function is to coat and protect the nucleoid to counteract adverse changes in DNA topology due to ionic shifts. 相似文献
39.
Ewa Witkowska Magda Godlewska Jowita Osiejuk Sandra Gtarz Beata Wileska Katarzyna Kosiska Joanna Starnowska-Sok Anna Piotrowska Piotr F. J. Lipiski Joanna Mataliska Jolanta Dyniewicz Pawe K. Halik Ewa Gniazdowska Barbara Przewlocka Aleksandra Misicka 《International journal of molecular sciences》2022,23(2)
Based on the mechanism of neuropathic pain induction, a new type of bifunctional hybrid peptidomimetics was obtained for potential use in this type of pain. Hybrids consist of two types of pharmacophores that are connected by different types of linkers. The first pharmacophore is an opioid agonist, and the second pharmacophore is an antagonist of the pronociceptive system, i.e., an antagonist of the melanocortin-4 receptor. The results of tests in acute and neuropathic pain models of the obtained compounds have shown that the type of linker used to connect pharmacophores had an effect on antinociceptive activity. Peptidomimetics containing longer flexible linkers were very effective at low doses in the neuropathic pain model. To elucidate the effect of linker lengths, two hybrids showing very high activity and two hybrids with lower activity were further tested for affinity for opioid (mu, delta) and melanocortin-4 receptors. Their complexes with the target receptors were also studied by molecular modelling. Our results do not show a simple relationship between linker length and affinity for particular receptor types but suggest that activity in neuropathic pain is related to a proper balance of receptor affinity rather than maximum binding to any or all of the target receptors. 相似文献
40.