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11.
Mark Bodner Emmanuel Bourret Jiri Patera Marzena Szajewska 《Acta Crystallographica. Section A, Foundations and Advances》2015,71(3):297-300
This paper completes the series of three independent articles [Bodner et al. (2013). Acta Cryst. A 69 , 583–591, (2014), PLOS ONE, 10.1371/journal.pone.0084079] describing the breaking of icosahedral symmetry to subgroups generated by reflections in three‐dimensional Euclidean space as a mechanism of generating higher fullerenes from C60. The icosahedral symmetry of C60 can be seen as the junction of 17 orbits of a symmetric subgroup of order 4 of the icosahedral group of order 120. This subgroup is noted by A1×A1, because it is isomorphic to the Weyl group of the semi‐simple Lie algebra A1×A1. Thirteen of the A1×A1 orbits are rectangles and four are line segments. The orbits form a stack of parallel layers centered on the axis of C60 passing through the centers of two opposite edges between two hexagons on the surface of C60. These two edges are the only two line segment layers to appear on the surface shell. Among the 24 convex polytopes with shell formed by hexagons and 12 pentagons, having 84 vertices [Fowler & Manolopoulos (1992). Nature (London), 355 , 428–430; Fowler & Manolopoulos (2007). An Atlas of Fullerenes. Dover Publications Inc.; Zhang et al. (1993). J. Chem. Phys. 98 , 3095–3102], there are only two that can be identified with breaking of the H3 symmetry to A1×A1. The remaining ones are just convex shells formed by regular hexagons and 12 pentagons without the involvement of the icosahedral symmetry. 相似文献
12.
In this paper the root polytopes of all finite reflection groups W with a connected Coxeter–Dynkin diagram in are identified, their faces of dimensions 0 ≤ d ≤ n − 1 are counted, and the construction of representatives of the appropriate W‐conjugacy class is described. The method consists of recursive decoration of the appropriate Coxeter–Dynkin diagram [Champagne et al. (1995). Can. J. Phys. 73 , 566–584]. Each recursion step provides the essentials of faces of a specific dimension and specific symmetry. The results can be applied to crystals of any dimension and any symmetry. 相似文献
13.
Marzena Filipowicz-Chomko Rafa&#x; Mierzwiak Marcin Nowak Ewa Roszkowska Tomasz Wachowicz 《Entropy (Basel, Switzerland)》2021,23(6)
Negotiation scoring systems are fundamental tools used in negotiation support to facilitate parties searching for negotiation agreement and analyzing its efficiency and fairness. Such a scoring system is obtained in prenegotiation by implementing selected multiple criteria decision-aiding methods to elicit the negotiator’s preferences precisely and ensure that the support is reliable. However, the methods classically used in the preference elicitation require much cognitive effort from the negotiators, and hence, do not prevent them from using heuristics and making simple errors that result in inaccurate scoring systems. This paper aims to develop an alternative tool that allows scoring the negotiation offers by implementing a sorting approach and the reference set of limiting profiles defined individually by the negotiators in the form of complete packages. These limiting profiles are evaluated holistically and verbally by the negotiator. Then the fuzzy decision model is built that uses the notion of increasing the preference granularity by introducing a series of limiting sub-profiles for corresponding sub-categories of offers. This process is performed automatically by the support algorithm and does not require any additional preferential information from the negotiator. A new method of generating reference fuzzy scores to allow a detailed assignment of any negotiation offer from feasible negotiation space to clusters and sub-clusters is proposed. Finally, the efficient frontier and Nash’s fair division are used to identify the recommended packages for negotiation in the bargaining phase. This new approach allows negotiators to obtain economically efficient, fair, balanced, and reciprocated agreements while minimizing information needs and effort. 相似文献
14.
Krzysztof Piasecki Ewa Roszkowska Tomasz Wachowicz Marzena Filipowicz-Chomko Anna &#x;yczkowska-Han&#x;kowiak 《Entropy (Basel, Switzerland)》2021,23(8)
We consider the negotiation problem, in which an agent negotiates on behalf of a principal. Our considerations are focused on the Inspire negotiation support system in which the principal’s preferences are visualised by circles. In this way, the principal describes the importance of each negotiation issue and the relative utility of each considered option. The paper proposes how this preference information may be implemented by the agent for determining a scoring function used to support decisions throughout the negotiation process. The starting point of our considerations is a discussion regarding the visualisation of the principal’s preferences. We assume here that the importance of each issue and the utility of each option increases with the size of the circle representing them. The imprecise meaning of the notion of “circle size” implies that in a considered case, the utility of an option should be evaluated by a fuzzy number. The proposed utility fuzzification is justified by a simple analysis of results obtained from the empirical prenegotiation experiment. A novel method is proposed to determine trapezoidal fuzzy numbers, which evaluates an option’s utility using a series of answers given by the participants of the experiment. The utilities obtained this way are applied to determine the fuzzy scoring function for an agent. By determining such a common generalised fuzzy scoring system, our approach helps agents handle the differences in human cognitive processes associated with understanding the principal’s preferences. This work is the first approach to fuzzification of the preferences in the Inspire negotiation support system. 相似文献
15.
Olga
wider Micha&#x; Wjcicki Marzena Bujak Edyta Juszczuk-Kubiak Magdalena Szczepa&#x;ska Marek &#x;. Roszko 《Molecules (Basel, Switzerland)》2021,26(19)
Salt concentrations in brine and temperature are the major environmental factors that affect activity of microorganisms and, thus may affect formation of biogenic amines (BAs) during the fermentation process. A model system to ferment cucumbers with low salt (0.5%, 1.5% or 5.0% NaCl) at two temperatures (11 or 23 °C) was used to study the ability of indigenous microbiota to produce biogenic amines and metabolize amino acid precursors. Colony counts for presumptive Enterococcus and Enterobacteriaceae increased by 4 and up to 2 log of CFU∙mL−1, respectively, and remained viable for more than 10 days. 16S rRNA sequencing showed that Lactobacillus and Enterobacter were dominant in fermented cucumbers with 0.5% and 1.5% salt concentrations after storage. The initial content of BAs in raw material of 25.44 ± 4.03 mg∙kg−1 fluctuated throughout experiment, but after 6 months there were no significant differences between tested variants. The most abundant BA was putrescine, that reached a maximum concentration of 158.02 ± 25.11 mg∙kg−1. The Biogenic Amines Index (BAI) calculated for all samples was significantly below that needed to induce undesirable effects upon consumption. The highest value was calculated for the 23 °C/5.0% NaCl brine variant after 192 h of fermentation (223.93 ± 54.40). Results presented in this work indicate that possibilities to control spontaneous fermentation by changing salt concentration and temperature to inhibit the formation of BAs are very limited. 相似文献
16.
The analysis of total vitamin C content in food is most frequently performed by reducing dehydroascorbic acid to ascorbic acid, which is then assayed with the technique of high-performance liquid chromatography combined with spectrophotometric detection. Tris(2-carboxyethyl)phosphine is currently the only agent in use that efficiently reduces dehydroascorbic acid at pH < 2. Therefore, there is a continued need to search for new reducing agents that will display a high reactivity and stability in acidic solutions. The objective of the study was to verify the applicability of unithiol and tris(hydroxypropyl)phosphine for a reducing dehydroascorbic acid in an extraction medium with pH < 2. The conducted validation of the newly developed method of determining the total content of vitamin C using tris(hydroxypropyl)phosphine indicates its applicability for food analysis. The method allows obtaining equivalent results compared to the method based on the use of tris(2-carboxyethyl)phosphine. The low efficiency of dehydroascorbic acid reduction with the use of unithiol does not allow its application as a new reducing agent in vitamin C analysis. 相似文献
17.
Alexopoulos T Allen C Anderson EW Areti H Banerjee S Beery PD Biswas NN Bujak A Carmony DD Carter T Cole P Choi Y De Bonte RJ Erwin AR Findeisen C Goshaw AT Gutay LJ Hirsch AS Hojvat C Kenney VP Lindsey CS LoSecco JM McMahon T McManus AP Morgan N Nelson KS Oh SH Piekarz J Porile NT Reeves D Scharenberg RP Stampke SR Stringfellow BC Thompson MA Turkot F Walker WD Wang CH Wesson DK 《Physical review letters》1990,64(9):991-994
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Rapidly solidified nanocomposite Nd9Fe77−xB14Tix alloys, consisting of magnetic Nd2Fe14B phase and soft magnetic phases, were investigated. The effect of titanium addition on the structure and magnetic properties was studied. It was found that 2–4 at% Ti addition leads to substantial increase of the coercivity and maximum energy product, maintaining the remanence unchanged. The highest properties: Jr=0.81 T, JHc=907 kA/m, (BH)max=99 kJ/m3, were achieved for the Nd9Fe73B14Ti4 alloy. This effect we attribute to the formation of fine and homogeneous grain structure and a change of the phase morphology in the Ti-containing alloys. The initial magnetization curve indicates a change of the coercivity mechanisms giving rise to pinning of domain walls, which is caused by reduction of the crystallite size. 相似文献