Deformation mechanism crossover and mechanical behaviour in nanocrystalline materials

We use molecular dynamics simulations to elucidate the transition with decreasing grain size from a dislocation- to a grain-boundary-based deformation mechanism in nanocrystalline fcc metals. Our simulations reveal that this crossover is accompanied by a pronounced transition in the mechanical behaviour of the material; namely, at the grain size where the crossover occurs (the 'strongest size'), the strain rate under tensile elongation goes through a minimum. This simultaneous transition in both the deformation mechanism and the corresponding mechanical behaviour offers an explanation for the experimentally observed crossover in the yield strength of nanocrystalline materials, from Hall-Petch hardening to 'inverse Hall-Petch' softening.     

Valence band structure of the NiAl–Mo alloy from the photoelectron spectrum

The valence band structures of the NiAl–Mo alloy was investigated by photoelectron spectroscopy. The valence band spectra of the NiAl–Mo alloy was shifted away from the Fermi level so that the Ni-d-band centroid moved to a higher energy by 0.22 eV as Mo was added. A possible explanation lied in the overlap of Ni-d bands in the energy with Mo-d and Al-p bands. The participation of Mo-d bands was correlated with the site preference of Mo in NiAl alloys.     

A structural model for surface-enhanced stabilization in some metallic glass formers

A structural model for surface-enhanced stabilization in some metallic glass formers is proposed. In this model, the alloy surface structure is represented by five-layer Kagomé-net-based lateral ordering. Such surface structure has intrinsic abilities to stabilize icosahedral-like short-range order in the bulk, acting as ‘a cloak of liquidity’. In particular, recent experimental observations of surface-induced lateral ordering and a very high glass forming ability of the liquid alloy Au₄₉Ag_5.5Pd_2.3Cu_26.9Si_16.3 can be united using this structural model. This model may be useful for the interpretation of surface structure of other liquid alloys with a high glass forming ability. In addition, it suggests the possibility of guiding the design of the surface coating of solid containers for the stabilization of undercooled liquids.     

Quasi-two-dimensional or hcp palladium nanoparticles with host-guest interaction prepared at room temperature

Quasi-two-dimensional palladium nanoparticles with an average lateral dimension of 7 nm have been prepared by reduction of a PdCl₂ graphite intercalation compound precursor by lithium-diphenylide in tetrahydrofuran at room temperature. Selected-area electron diffraction patterns provide evidence that the palladium nanoparticles are hcp single-crystal particles. Owing to the template effect of the graphite lattice, the lattice parameter of palladium was found to have a strong relation with the graphite, and a 3a _graphite superstructure was inferred. The palladium structure is rotated by 30^o with regard to the carbon host lattice. Raman spectroscopy on this sample showed that a charge transfer between carbon and palladium occurs. The sample can be considered as a common Pd-graphite intercalation compound with palladium nanoparticles as guest. This behaviour is different from palladium nanoparticles prepared by hydrogen reduction at higher temperatures from the same precursor material. These particles may represent an early stage of nanoparticle formation.     

Crystal growth and defect study of BiSbTe3

BiSbTe₃ single crystals have been grown by the Bridgman technique. Microscopic observations of the as-grown crystals reveal typical features, such as striations on the top free surface, which are attributed to the effect of growth conditions. A nitric-acid-based reagent capable of revealing dislocations has been developed and tested. Etch pits are produced at the dislocation sites, but some discrepancies have been observed on matched cleavage surfaces. The structural difference between the matched cleavage surfaces is discussed.     

Life: Definition,Origin, and Evolution

Out of all the natural phenomena surrounding us, the phenomena Life, as a matter of course, is that which is the most mysterious and least understood of all. In many aspects, it seems as though it would be possible to investigate, study, and explain Life, like so many of the other subjects that fall within the category of the natural sciences: time, space, mass, movement, and so on. However, in its essence, Life is organized and managed differently than all other natural phenomena, operating, as it were, according to its own laws. Life certainly has certain clearly recognizable characteristics, such as: metabolism, homeostasis, continuity, and more. However, up until the present time, no definition for Life has been provided, which unifies it as an entity, and differentiates it unmistakably from other natural phenomenon. The current article offers a definition of the true nature of the phenomenon of Life, which in turn helps to explain the big questions of life—evolution, the mind–body problem, consciousness, and more.     

Systems evolution,structures of long‐waves,and systems management

By classifying the evolution of systems into inter‐level evolution and intra‐level evolution and dividing the intra‐level evolution into four stages which are interrelated but quite different from each other, we discuss structures of several typical systems long‐waves, and strategies of systems management.     

Revisiting the dimensional structure of the emotion domain

Recent research has claimed that a novelty dimension is needed to represent the cognitive emotion structure over and above valence, power and arousal. Novelty emerged when student samples evaluated the meaning of 24 emotion terms on 142 emotion features. This claim is debatable, however, because to date novelty has never been found in similarity sorting studies. It is possible that novelty emerged because sophisticated student samples evaluated emotion terms on emotion features. The current research identified a large, representative set of emotion terms using a free-listing task in a middle childhood up to early adulthood sample (N = 5071). Children, adolescents, students and adults (N = 1184) then evaluated the similarity between these emotion terms using a similarity rating task without priming any emotion feature. Novelty robustly emerged as the fourth dimension. The existence of novelty is thus confirmed with a different method across a wide variety of participants.     

Perversion – structure or organization?

Abstract

This paper aims to discuss perversion, its implications in the clinical setting, and some of the key concepts around it. First, the etymology of the words “perversion”, “structure”, and “organization” is analyzed. Next follows a discussion on the sexual organization of instincts – from the Unconscious to the Oedipus complex in Freud and Lacan – setting the ground for a disavowal-based theory of perversion. An instructive approach has been chosen so as better to organize the various points presented.

Laender NR et al. Perversion – Struktur oder Organisation?

Der Aufsatz diskutiert die Perversion, ihre Auswirkungen im klinischen Setting und einige Schlüsselkonzepte. Zuerst wird die Herkunft der Wörter Perversion, Struktur und Organisation analysiert. Dann folgt eine Diskussion über die Organisation der Sexualität bzw. der Instinkte – vom Unbewussten bis zum Ödipuskomplex bei Freud und Lacan – wodurch eine Theorie der Perversion auf der Basis von Ablehnung begründet wird. Ein instruktiver Zugang, bei dem die verschiedenen Punkte von Interesse gut strukturiert sind, wurde gewählt.

Laender NR et al . Perversion – organización o estructura?

Este trabajo intenta discutir la perversión, sus implicaciones en la clínica y algunos de los conceptos clave alrededor de la perversión.

Primero, es analizada la etimología de las palabras Perversión, Estructura y Organización. Despúes sigue una discusión sobre la organización sexual de los instintos- desde lo Inconsciente hasta el complejo de Edipo en Freud y Lacan- planteando las bases para una teoría de la negación-desaprobación de la perversión.

Para organizar mejor los varios aspectos presentados se escogió una aproximación instructiva.