Superspace description of the homologous series Ga2O3(ZnO) m

2010 ◽  
Vol 66 (2) ◽  
pp. 117-129 ◽  
Author(s):  
Yuichi Michiue ◽  
Noboru Kimizuka
Keyword(s):  
Homologous Series ◽  
Ideal Model ◽  
Modulated Structure ◽  
Superspace Formalism ◽  
Alternative Settings ◽  
Complex Phenomena ◽  
Modular Structures ◽  
Unified Description ◽  
Superspace Description ◽  
The Ideal

A unified description for the structures of the homologous series Ga2O3(ZnO) m , gallium zinc oxide, is presented using the superspace formalism. The structures were treated as a compositely modulated structure consisting of two subsystems. One is constructed with metal ions and the other with O ions. The ideal model is given, in which the displacive modulations of ions are well described by the zigzag function with large amplitudes. Alternative settings are also proposed which are analogous to the so-called modular structures. The validity of the model has been confirmed by refinements for phases with m = 6 and m = 9 in the homologous series. A few complex phenomena in real structures are taken into account by modifying the ideal model.

Structure of (Ga2O3)2(ZnO)13 and a unified description of the homologous series (Ga2O3)2(ZnO)2 n + 1

2012 ◽  
Vol 68 (3) ◽  
pp. 250-260 ◽  
Author(s):  
Yuichi Michiue ◽  
Noboru Kimizuka ◽  
Yasushi Kanke ◽  
Takao Mori
Keyword(s):  
Homologous Series ◽  
Unit Cell ◽  
Dimensional Model ◽  
X Ray Diffraction ◽  
X Ray ◽  
Cell Parameters ◽  
Modulated Structures ◽  
Superspace Formalism ◽  
Complex Phenomena ◽  
Unified Description

The structure of (Ga2O3)2(ZnO)13 has been determined by a single-crystal X-ray diffraction technique. In the monoclinic structure of the space group C2/m with cell parameters a = 19.66 (4), b = 3.2487 (5), c = 27.31 (2) Å, and β = 105.9 (1)°, a unit cell is constructed by combining the halves of the unit cell of Ga2O3(ZnO)6 and Ga2O3(ZnO)7 in the homologous series Ga2O3(ZnO) m . The homologous series (Ga2O3)2(ZnO)2n + 1 is derived and a unified description for structures in the series is presented using the (3+1)-dimensional superspace formalism. The phases are treated as compositely modulated structures consisting of two subsystems. One is constructed by metal ions and another is by O ions. In the (3 + 1)-dimensional model, displacive modulations of ions are described by the asymmetric zigzag function with large amplitudes, which was replaced by a combination of the sawtooth function in refinements. Similarities and differences between the two homologous series (Ga2O3)2(ZnO)2n + 1 and Ga2O3(ZnO) m are clarified in (3 + 1)-dimensional superspace. The validity of the (3 + 1)-dimensional model is confirmed by the refinements of (Ga2O3)2(ZnO)13, while a few complex phenomena in the real structure are taken into account by modifying the model.

Modular crystals as modulated structures: the case of the lillianite homologous series

2008 ◽  
Vol 64 (6) ◽  
pp. 684-701 ◽  
Author(s):  
Luis Elcoro ◽  
J. M. Perez-Mato ◽  
Karen Friese ◽  
Václav Petříček ◽  
Tonči Balić-Žunić ◽  
...  
Keyword(s):  
Homologous Series ◽  
Robust Method ◽  
Composite Approach ◽  
Modulated Structures ◽  
Superspace Formalism ◽  
Study Case ◽  
Starting Model ◽  
Modular Structures ◽  
Composite Description

The use of the superspace formalism is extended to the description and refinement of the homologous series of modular structures with two symmetry-related modules with different orientations. The lillianite homologous series has been taken as a study case. Starting from a commensurate modulated composite description with two basic subsystems corresponding to the two different modules, it is shown how a more efficient description can be achieved using so-called zigzag modulation functions. These linear zigzag modulations, newly implemented in the program JANA2006, have very large fixed amplitudes and introduce in the starting model the two orientations of the underlying module sublattices. We show that a composite approach with this type of function, which treats the cations and anions as two separate subsystems forming a misfit compound, is the most appropriate and robust method for the refinements.

Superspace description of the crystal structures of Ca n (Nb,Ti) n O3n + 2 (n = 5 and 6)

2007 ◽  
Vol 63 (2) ◽  
pp. 183-189 ◽  
Author(s):  
Jonathan Guevarra ◽  
Andreas Schönleber ◽  
Sander van Smaalen ◽  
Frank Lichtenberg
Keyword(s):  
Crystal Structures ◽  
Homologous Series ◽  
Three Dimensional ◽  
Natural Explanation ◽  
Modulated Structures ◽  
Superspace Formalism ◽  
Superspace Description

The crystal structures of two members of the homologous series Ca n (Nb,Ti) n O3n + 2, with n = 5 and 6, are presented within the superspace formalism. A common (3 + 1)-dimensional superspace model is used to describe the crystal structures of both compositions within a particular homologous series, where the primary modulation wavevector and the width of the atomic domains vary systematically with composition. The two crystal structures are characterized as commensurately modulated structures consisting of discontinuous atomic domains described by occupational crenel functions. The displacive modulation functions for the two compounds exhibit similarities, but they also show that the idea of a unified superspace model does not extend toward the precise atomic positions. For n = 6, the centrosymmetric (3 + 1)-dimensional superspace symmetry provides a natural explanation for the pseudo-symmetries that are present in the non-centrosymmetric (three-dimensional) superstructure of this compound. The efficiency of the superspace approach is demonstrated by structure refinements in (3 + 1)-dimensional superspace and by comparing these results with the refinements in their three-dimensional superstructures.

Happiness, Virtue, and Political Society

2018 ◽  
Author(s):  
T. M. Rudavsky
Keyword(s):  
Moral Philosophy ◽  
Political Behavior ◽  
Political Society ◽  
Ideal Model ◽  
The Road ◽  
Doctrine Of The Mean ◽  
The Mean ◽  
The Ideal ◽  
Divine Law

Chapter 9 is concerned with social and political behavior. Even in the context of moral philosophy, Jewish philosophers discuss issues within the wider context of a rational scientific perspective. This chapter begins with specific moral codes developed by Jewish thinkers, focusing in particular upon the works of Ibn Gabirol, Baḥya ibn Paquda, Maimonides, and Crescas. Can there be ethical dictates independent of the commandments? The rabbis already worried whether there existed a domain of “right behavior” that pre-dates, or exists independently of, divine commandment. Does Aristotle’s doctrine of the mean apply to divine law? Furthermore, can all humans achieve intellectual perfection? Is the road the same, and open, to all? And is there only one road to ultimate felicity, or are there many routes? The chapter ends with a discussion of whether human felicity can be achieved in this life, and whether the prophet best represents the ideal model for such achievement.

scholarly journals Using argumentation theory to identify the challenges of shared decision-making when the doctor and the patient have a difference of opinion

2012 ◽  
Vol 1 (2) ◽  
pp. 26 ◽  
Author(s):  
Claudia A. Zanini ◽  
Sara Rubinelli
Keyword(s):  
Decision Making ◽  
Dispute Resolution ◽  
Shared Decision Making ◽  
Communication Skills ◽  
Critical Discussion ◽  
Argumentation Theory ◽  
Shared Decision ◽  
Ideal Model ◽  
Difference Of Opinion ◽  
The Ideal

This paper aims to identify the challenges in the implementation of shared decision-making (SDM) when the doctor and the patient have a difference of opinion. It analyses the preconditions of the resolution of this difference of opinion by using an analytical and normative framework known in the field of argumentation theory as the ideal model of critical discussion. This analysis highlights the communication skills and attitudes that both doctors and patients must apply in a dispute resolution-oriented communication. Questions arise over the methods of empowerment of doctors and patients in these skills and attitudes as the preconditions of SDM. Overall, the paper highlights aspects in which research is needed to design appropriate programmes of training, education and support in order to equip doctors and patients with the means to successfully engage in shared decision-making.

SUR L'APPROXIMATION DES BOSONS ET L'ANTISYMÉTRIE

1967 ◽  
Vol 45 (10) ◽  
pp. 3241-3245 ◽  
Author(s):  
P. A. Simard
Keyword(s):  
Ideal Space ◽  
Quasi Particle ◽  
Anharmonic Corrections ◽  
Spherical Nuclei ◽  
Unified Description ◽  
Boson Approximation ◽  
The Ideal

A method is presented in the scheme of the boson approximation such that the antisymmetry between the quasi-particles is introduced naturally. Based on the transcription of the quasi-particle into the ideal space, the method enables one to give a unified description of the anharmonic corrections in the even–even and odd spherical nuclei.

Analytical Solutions of the Ideal Model for Gradient Liquid Chromatography

2006 ◽  
Vol 78 (22) ◽  
pp. 7828-7840 ◽  
Author(s):  
Weiqiang Hao ◽  
Xiangmin Zhang ◽  
Keyong Hou
Keyword(s):  
Liquid Chromatography ◽  
Analytical Solutions ◽  
Ideal Model ◽  
Gradient Liquid Chromatography ◽  
The Ideal

A VISUAL METAPHOR OF THE MEDIEVAL SOCIETY IN THE LATE 15th - EARLY 16th CENTURIES RUSSIAN “IN THEE REJOICETH” ICONS

2021 ◽  
Vol 29 (1) ◽  
pp. 99-122
Author(s):  
Ludmila Sukina ◽  
Keyword(s):  
Capital City ◽  
Visual Metaphor ◽  
Ideal Model ◽  
Human Race ◽  
City Community ◽  
Russian State ◽  
Spiritual Authority ◽  
The City ◽  
The Ideal

The author examines the “In Thee rejoiceth” icons as visual sources that make it possible to reconstruct the ideal model of medieval society in the Moscow culture of the late 15th and early 16th centuries. This icon type, which includes the scenes of “Human race” collective praying to the Mother of God, is of Russian origin. Unlike other works of that time typologically close to it (“The Intercession”, “The Congregation of Our Lady”, “The Congregation of All Saints”, etc.), the “In Thee rejoiceth” icons demonstrate a historical connection to religious and socio-cultural facts of the Muscovy state. They clearly express the idea of Muscovy enjoying special patronage of the Mother of God, whose cult was actively developed in Moscow, the city that, as was believed at the Grand Dukes’ court, inherited the traditions and the spiritual authority of Constantinople. The depiction of the “Human race” in the “In Thee rejoiceth” icons can be viewed as a metaphorical image of the capital city community consisting of different groups of clergy and laity. This image corresponded to the ideas of the authorities and the population of the Russian state that existed under Ivan III and Vasili III.

Staročeskéite, Ag0.70Pb1.60(Bi1.35Sb1.35)Σ2.70S6, from Kutná Hora, Czech Republic, a new member of the lillianite homologous series

2018 ◽  
Vol 82 (4) ◽  
pp. 993-1005 ◽  
Author(s):  
Richard Pažout ◽  
Jiří Sejkora
Keyword(s):  
Czech Republic ◽  
Homologous Series ◽  
Electron Probe ◽  
New Mineral ◽  
Orthorhombic Space Group ◽  
Calculated Density ◽  
New Mineral Species ◽  
Reflected Light ◽  
Ore District ◽  
The Ideal

ABSTRACTA new mineral species, staročeskéite, ideally Ag0.70Pb1.60(Bi1.35Sb1.35)Σ2.70S6, has been found at Kutná Hora ore district, Czech Republic. The mineral occurs in the late-stage Bi-mineralization associated with other lillianite homologues (gustavite, terrywallaceite, vikingite, treasurite, eskimoite and Bi-rich andorite-group minerals) and other bismuth sulfosalts (izoklakeite, cosalite and Bi-rich jamesonite) in quartz gangue. The mineral occurs as lath shaped crystals or anhedral grains up to 80 µm × 70 µm, growing together in aggregates up to 200 µm × 150 µm across. Staročeskéite is steel-grey in colour and has a metallic lustre, the calculated density is 6.185 g/cm3. In reflected light staročeskéite is greyish white; bireflectance and pleochroism are weak with greyish tints. Anisotropy is weak to medium with grey to bluish grey rotation tints. Internal reflections were not observed. The empirical formula based on electron probe microanalyses and calculated on 11 apfu is: (Ag0.68Cu0.01)Σ0.69(Pb1.56Fe0.01Cd0.01)Σ1.58(Bi1.32Sb1.37)Σ2.69(S6.04Se0.01)Σ6.05. The ideal formula is Ag0.70Pb1.60(Bi1.35Sb1.35)Σ2.70S6, which requires Ag 7.22, Pb 31.70, Bi 26.97, Sb 15.72 and S 18.39 wt.%, total 100.00 wt.%. Staročeskéite is a member of the lillianite homologous series with N = 4. Unlike gustavite and terrywallaceite, staročeskéite, similarly to lillianite, is orthorhombic, space group Cmcm, with a = 4.2539(8), b = 13.3094(8), c = 19.625(1) Å, V = 1111.1(2) Å3 and Z = 4. The structure of staročeskéite contains four sulfur sites and three metal sites: one pure Pb site and two mixed sites, M1 (0.52Bi + 0.356Ag + 0.124Sb) and M2 (0.601Sb + 0.259Pb + 0.14Bi). The mineral is characterized by the Bi:Sb ratio 1:1 (Bi/(Bi + Sb) = 0.50) and the Ag+ + Bi3+, Sb3+ ↔ 2 Pb2+ substitution (L%) equal to 70%. Thus the mineral lies between two series of the lillianite structures with N = 4, between the lillianite–gustavite series and the andorite series.

scholarly journals Sports Training – Optimizing Mode of Improving the Motric Capacity in Preparation Military Students

2017 ◽  
Vol 22 (1) ◽  
pp. 30-34
Author(s):  
Robert Stănciulescu
Keyword(s):  
Exercise Capacity ◽  
Weather Condition ◽  
Human Potential ◽  
Military Students ◽  
Ideal Model ◽  
High Quality ◽  
The One ◽  
High Level ◽  
And Training ◽  
The Ideal

Abstract Specialized studies show how a fighter should physically be, not just any fighter, but the one who possesses the qualities and features of the ideal model, i.e. those elements that define the near-perfect fighter. The demands of the modern battlefield impose a high quality human potential that provides a good basis for the selection and training of fighters. Resistance to physical, climate, season and weather condition demands, to the prolonged efforts fighting requires is one of the important conditions of success. The paper presents information with particular impact in optimizing exercise capacity for future officers of the land forces, emphasizing once again the idea that a high level of motric ability is an essential objective.

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