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991.
Malgorzata Lewandowska Tomasz Wejrzanowski Krzysztof J. Kurzydłowski 《Journal of Materials Science》2008,43(23-24):7495-7500
Ultrafine grained materials can be produced by a number of techniques among which one can distinguish hydrostatic extrusion. In aluminium, this method can be used to obtain a structure with the grain size of 300 nm and high fraction of HAGBs (more than 70%). During annealing this structure undergoes significant changes which were evaluated quantitatively. Annealing for 1 h at temperatures up to 200 °C results in normal grain growth whereas at higher temperatures or for longer annealing times a transition from normal to abnormal growth is observed. The activation energy for low temperature regime is 43 kJ/mol whereas for high temperature annealing—128 kJ/mol. The former corresponds to grain boundary diffusion whereas the latter is close to activation energy of self diffusion in aluminium. The change in activation energy well corresponds to the transition in grain growth mechanism from normal to abnormal. 相似文献
992.
993.
Kuśmierczyk Filip Zimowski Sławomir Łukaszczyk Alicja Kopia Agnieszka Cieniek Łukasz Moskalewicz Tomasz 《Metallurgical and Materials Transactions A》2021,52(9):3880-3895
Metallurgical and Materials Transactions A - In this study, molybdenum disulfide nanosheets, bioactive hydroxyapatite particles of two types in various amounts, and PEEK 704 microparticles were... 相似文献
994.
MSQL: A Query Language for Database Mining 总被引:9,自引:1,他引:8
The tremendous number of rules generated in the mining process makes it necessary for any good data mining system to provide for powerful query primitives to post-process the generated rulebase, as well as for performing selective, query based generation. In this paper, we present the design and compilation of MSQL, the rule query language developed as part of the Discovery Board system. 相似文献
995.
Anna Bereznicka Krzysztof Mikolajczyk Katarzyna Szymczak-Kulus Katarzyna Kapczynska Edyta Majorczyk Anna Modlinska Tomasz Piasecki Radoslaw Kaczmarek Marcin Czerwinski 《International journal of molecular sciences》2021,22(18)
Most glycosyltransferases show remarkable gross and fine substrate specificity, which is reflected in the old one enzyme-one linkage paradigm. While human Gb3/CD77 synthase is a glycosyltransferase that synthesizes the Galα1→4Gal moiety mainly on glycosphingolipids, its pigeon homolog prefers glycoproteins as acceptors. In this study, we characterized two Gb3/CD77 synthase paralogs found in pigeons (Columba livia). We evaluated their specificities in transfected human teratocarcinoma 2102Ep cells by flow cytofluorometry, Western blotting, high-performance thin-layer chromatography, mass spectrometry and metabolic labelling with 14C-galactose. We found that the previously described pigeon Gb3/CD77 synthase (called P) can use predominately glycoproteins as acceptors, while its paralog (called M), which we serendipitously discovered while conducting this study, efficiently synthesizes Galα1→4Gal caps on both glycoproteins and glycosphingolipids. These two paralogs may underlie the difference in expression profiles of Galα1→4Gal-terminated glycoconjugates between neoavians and mammals. 相似文献
996.
In this study, the authors present a model of the inelastic impact of bodies that takes place during handling of unit loads (cubiform parcels). A modified non‐linear Kelvin model is proposed, in which the relationships between object strains and elastic and damping forces of the impact are represented by power functions. The results of analytical investigations on the proposed model were confirmed by experiments consisting in tests of free fall of the load on rigid ground and on elastic beam. The developed model allows the assessment of the influence of mechanical properties of loads and conveyor‐line deflection mechanisms as well as impact velocity, on the dynamic forces exerted on the manipulated objects during the impact. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
997.
Tomasz Borowski Agnieszka Brojanowska Marcin Kost Halina Garbacz Tadeusz Wierzcho 《Vacuum》2009,83(12):1489-1493
The nickel alloys of the Inconel type (containing above 15wt% of chromium), used in many industrial applications including the manufacture of aircraft, chemistry, power generation, and material processing, have advantageous mechanical properties, high plasticity and good corrosion resistance, but their frictional wear resistance is poor. This drawback can be obviated by subjecting the alloys to various surface treatments.The paper describes the structure and properties of nitrided layers produced on the Inconel 625 nickel alloy (20wt%Cr, 10wt%Mo, 5wt%Fe, 1wt%Co, balance-Ni). It has been found that the diffusion-type chromium nitride layer produced on the alloy surface improves the hardness, frictional wear resistance, fatigue strength and corrosion resistance of the alloy. It was demonstrated that the nitriding process can be successfully used for prolonging the service life of the fiberizing disc intended for the fabrication of what is known as glass wool. 相似文献
998.
Anna Bogda Andrzej Badeski Magorzata Pac Anna Wjcicka Marta Badeska Agnieszka Didyk Elbieta Trembecka-Dubel Nel Dbrowska-Leonik Magorzata Walaszczyk Natalia Matysiak Aurelia Morawiec-Knysak Tomasz Szczepaski Maria Szczepaska 《International journal of molecular sciences》2021,22(17)
Hemolytic uremic syndrome (HUS) is defined by the triad of microangiopathic hemolytic anemia, thrombocytopenia, and acute kidney injury (AKI). Atypical HUS (aHUS), distinguished by its etiology, is caused by uncontrolled overactivation of the alternative complement pathway. The correct diagnosis of aHUS is complex and involves various gene mutations. Severe combined immunodeficiency (SCID), characterized by severe T-cell lymphocytopenia and a lack of antigen-specific T-cell and B-cell immune responses, is of seldom occurrence. In 10–15% of pediatric patients, SCID is caused by adenosine deaminase (ADA) deficiency. The authors describe the case of a boy who suffered from both aHUS and ADA-deficient SCID. At the age of 9 months, the patient presented acute kidney injury with anuria and coagulopathy. The diagnosis of aHUS was established on the basis of alternative complement pathway deregulation and disease-associated gene mutations. Further examination revealed immune system failure and, at the age of 13 months, the ADA deficiency was confirmed by genetic tests and the boy was diagnosed with ADA-SCID. ADA SCID has recently been described as a possible triggering factor of aHUS development and progression. However, more research is required in this field. Nevertheless, it is crucial in clinical practice to be aware of these two co-existing life-threatening diseases. 相似文献
999.
Effect of supplementation of cows diet with linseed and fish oil and different variants of β‐lactoglobulin on fatty acid composition and antioxidant capacity of milk 下载免费PDF全文
1000.
Tomasz S. Wiltowski Kurt Sangster William S. O'Brien 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1996,67(2):204-212
This paper deals with catalytic reduction of SO2 with methane using molybdenum sulfide catalyst supported on two different activated carbons (Darco TRS and Norit ROZ-3). The experiments evaluated the effects of MoS2 catalyst loading (10%, 15%, and 20% Mo, by weight), gas feed-rate concentration ratios of CH4 to SO2 (CH4: SO2 ratios of 2: 1, 1: 1, and 1: 2) and reaction temperatures (450°C, 500°C, and 600°C). The reactivity of each catalyst was evaluated by three different parameters: (a) SO2 conversion, (b) CH4 conversion and (c) the yield of elemental sulfur. The results show that the catalytic activity of MoS2 supported on activated carbons is strongly related to the reaction temperature and the CH4 : SO2 feed ratio, with a secondary dependency on the loading of the MoS2. The 20% MoS2 catalyst supported on Darco TRS in a reactor stream with CH4 : SO2 = 1 : 1 demonstrated the highest activity of all the catalysts tested, having an SO2 conversion of 99·8%. At 600°C and with a CH4 : SO2 = 1 : 1, the catalysts with 20% loading supported on both Dacro TRS and Norit ROZ-3 exhibited comparable SO2 conversion, both above 90%. 相似文献