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1.
Microstructural transformations of heat affected zones in duplex steel welded joints 总被引:2,自引:0,他引:2
The influence of the welding thermal conditions exemplified by heat input and heat treatment after welding on the structure of the heat affected zone (HAZ) UNS S31803 has been analysed. The post weld treatment was used to create the precisely defined thermal conditions for the decomposition of primary phases in the HAZ, by a multi-layer welding thermal cycle stimulation. Detailed analyses of the microstructure and chemical composition of the phases in the different post welded conditions were performed by scanning electron microscopy (SEM) combined with energy dispersive spectrometry (EDS) and transmission electron microscopy (TEM). Three types of secondary precipitates have been observed: secondary austenite (γ2), carbides: M23C6 and M7C3. The dependence of the secondary austenite volume fraction and morphology in the HAZ on thermal cycle have been interpreted. The eutectoid decomposition of the primary phases in the analysed thermal conditions was confirmed. 相似文献
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Fast Recognition of Fibonacci Cubes 总被引:1,自引:0,他引:1
Fibonacci cubes are induced subgraphs of hypercubes based on Fibonacci strings. They were introduced to represent interconnection
networks as an alternative to the hypercube networks. We derive a characterization of Fibonacci cubes founded on the concept
of resonance graphs. The characterization is the basis for an algorithm which recognizes these graphs in O(mlog n) time.
A. Vesel supported by the Ministry of Science of Slovenia under the grant 0101-P-297. 相似文献
4.
Anna Iwaniak Damir Mogut Piotr Minkiewicz Justyna ulewska Magorzata Darewicz 《International journal of molecular sciences》2021,22(6)
In silico and in vitro methods were used to analyze ACE- and DPP-IV-inhibiting potential of Gouda cheese with a modified content of β-casein. Firstly, the BIOPEP-UWM database was used to predict the presence of ACE and DPP-IV inhibitors in casein sequences. Then, the following Gouda cheeses were produced: with decreased, increased, and normative content of β-casein after 1 and 60 days of ripening each (six variants in total). Finally, determination of the ACE/DPP-IV-inhibitory activity and the identification of peptides in respective Gouda-derived water-soluble extracts were carried out. The identification analyses were supported with in silico calculations, i.e., heatmaps and quantitative parameters. All Gouda variants exhibited comparable ACE inhibition, whereas DPP-IV inhibition was more diversified among the samples. The samples derived from Gouda with the increased content of β-casein (both stages of ripening) had the highest DPP-IV-inhibiting potency compared to the same samples measured for ACE inhibition. Regardless of the results concerning ACE and DPP-IV inhibition among the cheese samples, the heatmap showed that the latter bioactivity was predominant in all Gouda variants, presumably because it was based on the qualitative approach (i.e., peptide presence in the sample). Our heatmap did not include the bioactivity of a single peptide as well as its quantity in the sample. In turn, the quantitative parameters showed that the best sources of ACE/DPP-IV inhibitors were all Gouda-derived extracts obtained after 60 days of the ripening. Although our protocol was efficient in showing some regularities among Gouda cheese variants, in vivo studies are recommended for more extensive investigations of this subject. 相似文献
5.
Aleksander Peczenik 《Artificial Intelligence and Law》1996,4(3-4):297-329
The main stream of legal theory tends to incorporate unwritten principles into the law. Weighing of principles plays a great role in legal argumentation, inter alia in statutory interpretation. A weighing and balancing of principles and other prima facie reasons is a jump. The inference is not conclusive.To deal with defeasibility and weighing, a jurist needs both the belief-revision logic and the nonmonotonic logic. The systems of nonmonotonic logic included in the present volume provide logical tools enabling one to speak precisely about various kinds of rules about rules, dealing with such things as applicability of rules, what is assumed by rules, priority between rules and the burden of proof. Nonmonotonic logic is an example of an extension of the domain of logic. But the more far-reaching the extension is, the greater problems it meets. It seems impossible to make logical reconstruction of the totality of legal argumentation.The lawyers' search for reasons has no obvious end point. Ideally, the search for reasons may end when one arrives at a coherent totality of knowledge. In other words, coherence is the termination condition of reasoning. Both scientific knowledge and knowledge of legal and moral norms progresses by trial and error, and that one must resort to a certain convention to define what error means. The main difference is, however, that conventions of science are much more precise than those of legal scholarship.Consequently, determination of error in legal science is often holistic and circular. The reasons determining that a legal theory is erroneous are not more certain than the contested theory itself. A strict and formal logical analysis cannot give us the full grasp of legal rationality. A weaker logical theory, allowing for nonmonotonic steps, comes closer, at the expense of an inevitable loss of computational efficiency. Coherentist epistemology grasps even more of this rationality, at the expense of a loss of preciseness. 相似文献
6.
A Review of Critical Plane Orientations in Multiaxial Fatigue Failure Criteria of Metallic Materials 总被引:1,自引:0,他引:1
The paper presents a review of multiaxial fatigue failure criteria based on the critical plane concept. The criteria have
been divided into three groups, according to the fatigue damage parameter used in the criterion, i.e. (i) stress, (ii) strain
and (iii) strain energy density criteria. Each criterion was described mainly by the critical plane orientation. Multiaxial
fatigue criteria based on the critical plane concept usually apply different loading parameters in the critical plane whose
orientation is determined by (a) only shear loading parameters (crack Mode II or III), (b) only normal loading parameters
(crack Mode I) or sometimes (c) mixed loading parameters (mixed crack Mode). There are also criteria based on few critical
plane orientations and criteria based on critical plane orientations determined by a weighted averaging process of rotating
principal stress axes. 相似文献
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9.
Barbara Mendrek Łukasz Sieroń Marcin Libera Mario Smet Barbara Trzebicka Aleksander L. Sieroń Andrzej Dworak Agnieszka Kowalczuk 《Polymer》2014
Core-shell type stars synthesized via atom transfer radical polymerization were used for the delivery of nucleic acids. The interior of the stars consisted of hyperbranched poly(arylene oxindole), while the arms were composed of poly(N,N-dimethylaminoethyl methacrylate). The length of the star arms varied in degree of polymerization (DP) from 14 to 98. The hydrodynamic radius of the structures measured in water indicated the presence of small aggregates, while isolated stars ranging in size from 14 to 29 nm were seen in organic solvent. The phase transition temperatures of the stars in water, measured in basic conditions, were shifted to lower values with increasing DP of the arms. Stable polyplexes of stars with plasmid DNA were formed. Their size varied from 300 nm to 400 nm, depending upon the DP of arms. The zeta potential of the polyplexes was positive, which facilitated their cellular uptake. The DP of the arms influenced the transfection efficiency of HT-1080 cells, demonstrating that stars are promising candidates for synthetic gene vectors. 相似文献