bluuebunny/crossref_metadata_2025 huggingface dataset:
Fremde Galaxien und abstrakte Welten
Authors: Taubert Niels
Published: April 2019

Frei zugängliches digitales Publizieren wird innerhalb der Scientific Community intensiv diskutiert. Dennoch ist nur wenig darüber bekannt, wie sich das wissenschaftliche Kommunikationssystem mit der Nutzung von Open Access verändert. An den Beispielen der Astronomie und Mathematik untersucht Niels Taubert im Ländervergleich Deutschland/Südafrika die Besonderheiten der darauf basierenden Sozialität und erklärt, wie die Organisation der freien Zugänglichkeit von Publikationen die Rollen der Beteiligten formt. Die Studie trägt damit nicht nur zur Etablierung einer wissenschaftssoziologischen Informationsinfrastrukturforschung bei, sondern leistet mit Blick auf die wissenschaftspolitische Debatte auch soziologische Aufklärung.
Kolonialität und Geschlecht im 20. Jahrhundert
Authors: Purtschert Patricia
Published: April 2019

Auf welche Weise ist Kolonialität an der Herausbildung von Geschlecht beteiligt? Diese Frage erörtert Patricia Purtschert am Beispiel der Schweiz im 20. Jahrhundert. Dabei wird der Blick auf zwei Figuren gerichtet, die zentral sind für die Herstellung der Schweizer Nation: die »Hausfrau« und der »Bergsteiger«. Die Studie zeichnet nach, wie die bürgerliche Hausfrau, die als Norm für die Schweizerin fungiert, in ständiger Abgrenzung von rassifizierten Anderen als weiße Vorsteherin einer zivilisierten und konsumorientierten Häuslichkeit entworfen wird. Im Unterschied dazu entsteht das Ideal des weißen Bergsteigers, das als Vorbild für den männlichen Schweizer Bürger dient, im kolonialen Wettstreit um die höchsten Gipfel der Welt. Koloniales Weiß-Machen erweist sich in dieser postkolonialen Analyse als grundlegendes Element einer zutiefst vergeschlechtlichten Nation.
The painter as professional observer
Authors: Krispinsson Charlotta
Published: April 2019

Charlotta Krispinsson explores in her chapter »The Painter as Professional Observer: Eye-witnessing through Portraiture in Early Twentieth-Century Art Historiography« German-language art-historical texts on early modern portraiture from the beginning of the twentieth century. This was a point in time when the history and ontology of portraiture was established as its own field of research within art history. Krispinsson argues that the sitting was given renewed value as more than just an opportunity for the artist to render the external features of the sitter's face and body, clothes and hair. The sitting came to be conceptualised as a key event that shaped the portrait painter's impression and perception of who the sitter was, turning the painter into a professional observer and interpreter of the sitter's individual characteristics and personality traits. At the beginning of the twentieth century, the portrait sitting came to be considered by art historians an act of eye-witnessing of a more complex kind, in which not only what was seen but also what was understood played a role.
»Ein furchtbarer Haß stieg in ihm auf.«
Authors: Winterstein Stefan
Published: April 2019

Stefan Winterstein widmet sich Franz Innerhofers Roman »Schöne Tage« (1974), der von der Forschung bislang vorwiegend unter den Schlagwörtern »Heimatliteratur« bzw. »Anti-Heimatliteratur« verbucht wurde. Der Beitrag führt vor, dass sich der Roman in doppelter Weise als Hasstext verstehen lässt: Der Hass ist einerseits Romanthema, sodass sich aus Beobachtungen am Text Rückschlüsse auf das außertextliche Phänomen Hass ziehen lassen. Andererseits dient der Hass aber auch als literarische Quelle und Motor; sohin als Strukturprinzip verstanden, lässt sich an ihm das innertextliche Funktionieren des Romans untersuchen. Die Bezeichnung als Hasstext ist dabei eine vom Interpreten zugeschriebene und doch wieder nicht: Denn auch wenn er vom Autor selbst nicht so bezeichnet wird, legt der Roman, wie Winterstein zeigt, seine eigene Konstruktion als Hasstext durchaus offen.
Hass als kritische Haltung?
Authors: Wagner-Egelhaaf Martina
Published: April 2019

Der Beitrag beschäftigt sich mit Max Billers Hass-Kolumnen »Hundert Zeilen Hass«, die zwischen 1986 und 1996 in der Zeitschrift »Tempo« und 2017 nochmals gesammelt als Buch erschienen. Er ordnet Billers kritisch-sarkastische Auseinandersetzung mit den gesellschaftlichen Verhältnissen in Deutschland in die aktuelle Hass-Debatte ein, die durch eine neue Konjunktur des Wortes »Hass« und seiner Attribution bestimmt ist.
Moral Bricolage - über das Gute sprechen
Authors: Hobl Barbara
Published: April 2019

Taumelt der Mensch? Es scheint kein intellektuelles Angebot in der Lage zu sein, den gesellschaftlichen Diskurs über den offensichtlich desolaten Zustand unserer Welt mit einer starken Idee an sich zu ziehen. Warum ist es so schwer, über das Gute zu sprechen? Mit einem fein gewebten und überraschenden Entwurf gibt Barbara Hobl hier mit ihrem Ansatz der »Bricolage« eine Antwort. Sie schlägt in einem disziplinübergreifenden Gedankengang vor, wie dem allgegenwärtigen Bösen eine eigene Qualität, eine Dynamik des Guten, entgegengehalten werden kann. Der Begriff der Paradoxie wird dabei neu aufgelegt: als ›Drehmoment‹, das den Denkraum öffnet. Die Kraft der Negativität sowie die Notwendigkeit, unsere Wirklichkeit bricolierend sowohl mit Wahrheit als auch mit Fiktion in Verbindung zu bringen, sind dafür zentral.
Projektbeschreibung: Würde im Stadtraum
Authors: Krämer-Hoppe Rike , Mosayebi Reza , Radermacher Martin , Weber Philipp
Published: April 2019

Dieser Beitrag präsentiert ein Teilprojekt der Arbeitsgruppe »Spaces of Dignity«, gefördert vom Mercator Research Center Ruhr im Rahmen der Global Young Faculty V. Er stellt Ziele, Vorgehensweise und Ergebnisse des Projekts vor und thematisiert dabei unter anderem die folgenden Fragen: Wie ermöglichen und beschränken materiell-räumliche Infrastrukturen ein menschenwürdiges Zusammenleben im Stadtraum? Inwiefern erlauben urbane Räume Einzelnen und Gruppen, sich in würdiger Weise zu entfalten? Als Fallbeispiel wird die Dortmunder Nordstadt, insbesondere das Quartier am Nordmarkt, untersucht.
Strukturen des Affektiven
Authors: Dahms Susann
Published: April 2019

»Affektivität« steht für etliche Phänomene wie Emotionen, Stimmungen, Grundgestimmtheiten und affektive Hintergründe. Häufig nehmen Forschungsansätze diese separat in den Blick. Susann Dahms geht indes der Frage nach dem Affektiven grundlegend nach. In der Besprechung inhärenter Strukturen des Affektiven der Resonanztheorie Hartmut Rosas sowie des Modells Emotionaler Energie von Randall Collins wird die Begegnung als bedeutsamer Ort der Generierung und Realisierung des Affektiven diskutiert. Kulturell prädisponierte Aufmerksamkeiten bringen dabei die elementarste und unsichtbarste Verschränkung sozialer Bedeutungen mit den affektiven Hintergründen der Individuen ins Gespräch.
L’émergence de l’allophonie comme construction d’une politique éducative
Authors: Armagnague Maïtena , Tersigni Simona
Published: April 2019

Fondé sur une méthodologie qualitative associant monographies et entretiens réalisés dans huit établissements durant trois années scolaires, cet article analyse ce que le qualificatif d’allophone produit comme catégorisation scolaire et mécanisme de filtrage institutionnel, dissociant les élèves migrants entre eux, en référence à une norme implicite de francophonie. Alors que les politiques éducatives prétendent promouvoir l’accessibilité, l’allophonie étiquette les élèves et les hiérarchise sous sa forme « totale » et « tempérée ». Une telle dynamique entérine une forme de sélection scolaire en pratiquant un aggiornamento de la rhétorique selon laquelle certains enfants seraient « sauvables » par l’école, tandis que d’autres ne le seraient pas. La désignation d’« allophone » peut alimenter de multiples formes de minorisation entre élèves ainsi qu’entre les élèves migrants et les adultes en charge d’eux dans les établissements scolaires.
Les pratiques des professionnelles de la petite enfance en Inde du Sud
Authors: Ponceaud Goreau Émilie
Published: April 2019

L’article propose de comprendre comment l’attitude des enseignantes du préscolaire au Tamil Nadu et à Pondichéry peut faire progresser les relations entre les familles et les institutions et valoriser les savoirs construits par les professionnelles. Tout d’abord, les étapes de la diffusion de la préscolarisation ainsi que la diversité des attentes exprimées vis-à-vis de l’école seront clarifiées dans le contexte particulier de l’Inde du Sud. Ensuite, l’article s’intéressera plus particulièrement à la manière dont les enseignantes du préscolaire créent un lien avec les familles et comment elles construisent des compétences expérientielles.
Innowacyjny nauczyciel, czyli kto? Próba definicji pojęcia
Authors: Półtorak Ewa , Gałan Beata
Published: April 2019

Innovativeness constitutes one of the core elements of modern ducation development. The phenomenon in question can be analysed in the context of the actions taken by each of the participants of the learning/teaching process. The paper is focused mostly on the teacher’s activity. On the basis of an empirical study, the Authors aim at defining the notion of an innovative teacher, and, more specifically, a language teacher.
Detrital zircon trace elements from the Mesozoic Jiyuan Basin, central China and its implication on tectonic transition of the Qinling Orogenic Belt
Authors: Wang Min , Guo Wenfei , Yang Wentao
Published: April 2019

The Qinling Orogen and the Jiyuan Basin constitute a basin-mountain system during the Early Mesozoic. Therefore, sediments from the Jiyuan Basin can be used to deduce the orogenic process of the Qinling Orogen. This paper attempts to use detrital zircon trace elements with ages ranging from the Late Carboniferous to the Middle Triassic that were obtained from the Jiyuan Basin to discuss the tectonic evolution of Qinling Orogen. On the tectonic setting discriminating diagrams, most grains are concentrated in convergent continental margins/orogenic settings,whereas the remaining samples (268 Ma, 265Ma, 264 Ma and 254Ma) are plotted in anorogenic field. Compared to the Early Paleozoic (400-500Ma) zircons, 306Ma and 281Ma grains represent higher Th/ Nb ratios, which might be related to the Mianlve oceanic crust subduction. The lower Th/Nb ratios containing 268 Ma, 265Ma, 264 Ma and 254Ma grains might indicate lithospheric extension subsequently. The final continent-continent collision between South China and North China blocks took place after the Middle Triassic (242Ma).
Herennius Dexippus und die Tradition der Perserkriege im Imperium Romanum
Authors: Rollinger Robert
Published: April 2019

Der Beitrag setzt sich kritisch mit der Bedeutung des Narratives „Perserkriege“ im Imperium Romanum vom 1. bis 3. Jahrhundert n. Chr. auseinander. Ausgangspunkt der Überlegungen bildet ein erst kürzlich entdecktes Fragment des am Ende des 3. Jahrhunderts n. Chr. schreibenden Herennius Dexippus, das ausführlich diskutiert und in einen größeren historischen Kontext gestellt wird. Dabei wird deutlich, dass die Perserkriege zwar auch im Imperium eine breite literarische Rezeption erfuhren, dass sie jedoch nicht jene Bedeutung in der ‚offiziellen‘ Reichsideolgie hatten, die ihnen von der modernen Forschung gemeinhin zugeschrieben wird. Zwar mögen griechische Intellektuelle, die stark auf Athen fokussiert waren, die Auseinandersetzung mit den Parthern und Sasaniden im Kontext der Perserkriege nach wie vor als eine ständige Konfrontation zwischen Asien und Europa gesehen haben, doch entsprach dies keineswegs einem von ‚offiziellen‘ Stellen verbreiteten Deutungsmuster. Diese griffen zur Legitimation ihrer Politik vielmehr auf andere historische Ereignisse zurück, denen als Bezugspunkt eine wesentlich größere Rolle zukam. Neben dem Alexanderfeldzug scheint dabei der Syrische Krieg gegen Antiochos III., den „König Asiens“, eine besondere Rolle gespielt zu haben.
Machtkalkül und Effizienzstreben. Lloyd George, der Kernbereich der britischen Exekutive und die institutionelle Ausformung eines Mehrebenensystems (1916–1919)
Authors: Wolf Klaus
Published: April 2019

Der Essay hinterfragt die weitverbreitete Ansicht, Lloyd George habe bei seinem Amtsantritt 1916 ein premierministerielles Regierungssystem im Vereinigten Königreich eingeführt. Ausgehend von R. A. W. Rhodes’ Definition von „Core Executive“ und S. Piattonis Definition von Mehrebenenpolitik werden die Interaktionen zwischen zentralen Akteuren und die organisatorischen Neuerungen auf gesamt-, sub- und suprastaatlicher Ebene untersucht. Hierdurch gelingt eine Präzisierung des Begriffs „executive prime minister“, den P. Dunleavy und G. W. Jones dazu verwenden, eine Fokussierung auf die vollziehende Gewalt und die Vernachlässigung parlamentarischer Aufgaben zu beschreiben. Angesichts des Ersten Weltkriegs und seiner Folgen gab Lloyd George nicht nur der britischen Exekutive einen leistungsstarken Kernbereich, sondern trieb im Rahmen des British Empire, der alliierten Kriegsführung und der Pariser Friedenskonferenz auch die Institutionalisierung der Steuerungs-, Koordinierungs- und Verhandlungssysteme auf supranationaler Ebene voran. Auf substaatlicher Ebene verschärfte sich indes die Destabilisierung der politischen Ordnung, als das von Lloyd George zur Lösung der Irischen Frage initiierte Partizipationsverfahren scheiterte. Bei den institutionellen Reformen und der Verlagerung politischer Kompetenzen verband er das Ziel gesteigerter Effizienz stets mit dem Wunsch, den Einfluss missliebiger Akteure zu reduzieren. Die grundsätzliche Abhängigkeit des Premiers von der Mitwirkung der Core Executive blieb jedoch auf allen Ebenen bestehen.
Evaluation of agricultural soil radiotoxic element pollution around a lignite-burning thermal power plant
Authors: Turhan Şeref
Published: April 2019

Lignite coal is a major and an essential domestic energy source in Turkey. Many environmental problems and human health hazards may arise during lignite coal exploitation, combustion, and waste (fly and bottom ash and slag) disposal. In addition, lignite-burning power plants can be significant contributors to deposition of radiotoxic elements and/or toxic heavy metals on soil and water. The concentrations of thorium (Th) and uranium (U) in a 140 agricultural soil samples collected from the vicinity of a lignite-burning thermal power plant (LBTPP), located in Kangal district of Sivas province in the Central Anatolia region of Turkey, were determined using energy dispersive X-ray fluorescence spectroscopy. The concentrations of Th and U varied from 2.9 to 12.7 μg g−1 with an average value of 5.8 μg g−1 and 0.3–12.3 μg g−1 with an average value of 1.5 μg g−1, respectively. The radiotoxic elements pollution in agricultural soils was evaluated using pollution indices such as geo-accumulation index (I
geo), enrichment factors (E
F

), pollution index (P
I

) and Nemerow integrated pollution index (NIP

I
). The average value of I
geo, E
F

and P
I

estimated for Th and U were found as −1.8, 1.2 and 0.44 and −1.7, 1.7 and 0.58, respectively. The results indicated that the soils around Kangal LBTPP were practically unpolluted to low polluted with Th and U. The NIP

I
values varied from 0.3 to 4.0 with an average value of 0.6. The evaluation result of NIP

I
revealed that 86 % of total soil samples were non-polluted.
Dirac Material Graphene
Authors: Sheka Elena F.
Published: April 2019

The paper presents an overview of graphene electronic structure in light of a general concept of emergent phenomena that result from the quantum phase transition caused by continuous symmetry breaking. In the current case, the spin symmetry breaking is provided by a drastic enhancement of pz odd electron correlation when the shortest distance between them, defined by C=C bond length, exceeds critical value Rcri. The UHF formalism clearly evidences the broken symmetry occurrence and perfectly suits to self-consistent description of the issue. Empirically supported and convincingly certified, the UHF emergents, such as (i) open-shell character of electron spinorbitals; (ii) spin polarization of electron spectrum; (iii) spin contamination; (iv) depriving the spin multiplicity of electronic states; (v) local spin pool at zero total spin density, and so forth greatly extend the view on ground states of graphene and other sp2 nanocarbons and not only give a clear vision of spin peculiarities of graphene chemistry but predicatively point to the occurrence of emergents related to graphene physics, such as ferromagnetism, superconductivity and topological nontriviality. The paper presents numerous experimental evidences supporting a deep interrelationship between emergent chemistry and emergent physics of graphene.
A Brief Review on Importance of Surface Texturing in Materials to Improve the Tribological Performance
Authors: Arumugaprabu V. , Ko Tae Jo , Kumaran Thirumalai , Kurniawan Rendi , Uthayakumar M.
Published: April 2019

Surface texturing in materials is one of the current process that satisfying the industrial needs and providing ample support to the production managers in machining. During machining for producing various products the major task is the reduction of materials waste, assessment of tool wear and its happening. Tool wear affects the production cost severely also incurring the material waste. One of the effective methods to reduce this problem and improving the tool life considerably is the surface texturing process. This can be carried out in work piece material neither the tool also. Surface texturing done on the surface of the tool or the work piece material to give aesthetic look alsomainly enhances the performance in various aspects.Many industrialists and researchers carried out the surface texturing process for various machining applications such as lathe, milling with various surface texturing techniques. This article present a detail review about the need for surface texturing in materials , its importance and its role in tool life enhancement had been discussed and reported.
Application of Iron Oxide Nanoparticles in Contemporary Experimental Physiology and Cell Biology Research
Authors: Nikolovski Dubravka , Jeremic Marta , Paunovic Jovana , Vucevic Danijela , Radosavljevic Tatjana , Radojević-Škodrić Sanja , Rakocevic Rastko , Nesic Dejan , Pantic Igor
Published: April 2019

Recent findings have suggested that iron oxide nanoparticles (IONPs) have some exceptional chemical characteristics which make them useful in both experimental physiology and cell biology research. These nanoparticles might be applied as drug delivery systems for anti-cancer and other medications. Also, IONPs might be a valuable part of many novel bioassays in various fundamental medical fields. In recent years, several studies have indicated that IONPs may have certain cytotoxic and genotoxic potential in living systems. During in vitro conditions, IONPs might induce generation of reactive oxygen species and cause oxidative stress in some cell populations. The toxicity of IONPs is not yet fully understood, and additional research is needed to confirm if IONPs have detrimental effects on human health. This short article focuses on the recent developments and trends in the fields of nanomedicine and nanobiology regarding iron oxide nanomaterials and their application in fundamental medical disciplines such as experimental physiology. We discuss our previously published works on structural effects of IONPs and other metallic nanoparticles on cell nucleus in in vitro conditions. We also describe our recent findings regarding the impact of IONPs on certain biophysical properties of subcellular components.
Synthesis and Applications of Nano Titania Particles: A Review
Authors: Khitab A. , Ahmad S. , Munir M.J. , Kazmi S.M.S. , Arshad T. , Khushnood R.A.
Published: April 2019

This paper reviews the synthesis methods of nano titania particles and their utilization in various applications with concise discussion on the related health concerns. Owing to the efficient photocatalytic properties of nano titania particles along with high stability, super hydrophilicity and low cost, these particles are perfect candidate for the production for coatings on the surfaces of construction materials i.e. tiles, facades, wall etc. The nano titania coatings are capable of decomposing dust, dirt and organic pollutants in the presence of sunlight. These decomposed products may then easily be washed away by rinsing thus providing easy cleaning and keeps the buildings in younger or fresh look for decades.
Emerging Advanced Nanomaterials for Cancer Photothermal Therapy
Authors: Zhang Haohao , Chen Guihuan , Yu Bing , Cong Hailin
Published: April 2019

As a new minimally invasive technique, photothermal therapy has attracted worldwide attention in the treatment of cancer. Photothermal therapy kills cancer cells by converting photon energy into heat energy. At the time of selection, the photothermal agents will be required to be water solubility, cytotoxicity, high photothermal conversion efficiency, metabolic pathway and so on. This report introduces the current research status of various nanoparticles used in photothermal therapy, and looks forward to the future development of photothermal therapy.
A Review on Recent Advances in Transient Liquid Phase (TLP) Bonding for Thermoelectric Power Module
Authors: Jung D. H. , Sharma A. , Mayer M. , Jung J. P.
Published: April 2019

In this study, the authors have reviewed recent advances on the transient liquid phase (TLP) bonding technology for various applications especially power module packaging in view of the recent increasing demand for the production of vehicles, smartphones, semiconductor devices etc. TLP bonding is one of the potential technologies from clean technology that can replace the Pb-base solder technology without causing any serious environmental issues. It is based on the concept of both brazing as well as diffusion bonding. During TLP bonding, the liquid phase is transiently formed at the bonding interface. At this point, the melting point of filler metal increases due to the diffusion of element which degrades the melting point from liquid phase to base metal. Subsequently, the bonding occurs by isothermal solidification at the bonding temperature of liquid phase. Here, after bonding, the melting temperature of the joint layer becomes higher than bonding temperature. This review introduces the various aspects of TLP bonding including its principle, materials, applications, advantages and properties in detail.
On the Common Origin of Structural Superplasticity in Different Classes of Materials
Authors: Padmanabhan K. A. , Basariya M. Raviathul
Published: April 2019

The present model starts with an assumption that grain/ interphase boundary sliding (GBS) that is dominant during optimal superplastic flow is slower than the accommodation processes of dislocation emission from sliding boundaries, highly localized diffusion in the boundary regions and/ or grain rotation that are present as a concomitant of the GBS process. When boundary sliding develops to a mesoscopic scale (of the order of a grain diameter or more), by the alignment of contiguous boundaries, plane interface formation/ mesoscopic boundary sliding is observed. Significant and simultaneous sliding along different plane interfaces and their interconnection can lead to large scale deformation and superplasticity. The accommodation steps, being faster than GBS, do not enter the strain rate equation. Mathematical development of these ideas using transition state theory results in a transcendental strain rate equation for steady state optimal superplastic flow, which when solved numerically helps one to describe the phenomenon quantitatively in terms of two constants, the activation energy for the rate controlling process, ΔF0and the threshold stress needed to be overcome for the commencement of mesoscopic boundary sliding, σ0.The analysis also explains quantitatively texture randomization as a function of superplastic strain. It is also pointed out, without going into details, that recently the problem has been reduced to FOUR “universal” constants, viz. the mean strain associated with a unit boundary sliding event g0, specific grain boundary energy γB, which is assumed to be isotropic, N the average number of boundaries that align to form a plane interface during mesoscopic boundary sliding and “a” a grain-size- and shape- dependent constant that obeys the condition 0 <a <0.5, in terms of which one can account for superplasticity in any material. In combination with the regression equations popularized by Frost and Ashby to predict the shear modulus of any material at any temperature, these four constants allow one to predict the steady state strain rate of any structurally superplastic material accurately, including those whose superplastic response is not considered for the analysis. The details of the last mentioned result, which are unpublished, will be presented elsewhere.
Hydrogen Embrittlement of Ultrafine-Grained Austenitic Stainless Steels
Authors: Astafurova E. G. , Astafurov S. V. , Maier G. G. , Moskvina V. A. , Melnikov E. V. , Fortuna A. S.
Published: April 2019

The effect of electrochemical hydrogen-charging on tensile properties, mechanisms of plastic deformation and fracture micromechanisms was studied using two ultrafine-grained (UFG) Cr-Ni austenitic stainless steels. UFG austenitic structures with an average subgrain size of 200 nm for CrNiMo (316L-type) and 520 nm for CrNiTi (321-type) steel were produced using hot-to-warm ABC-pressing. Hydrogen-charging up to 100 hours weakly influences stages of plastic flow, strength properties and elongation of the UFG steels. TEM analysis testifies to hydrogen-assisted partial annihilation and rearrangement of dislocations into dislocation tangles, and to hydrogen-induced variation in ratio of low- and high-angle misorientations in UFG structure of both steels. Hydrogen-alloying promotes mechanical twinning and deformation-induced γ ® e martensitic transformation in the UFG steels under tension. Ultrafine-grained CrNiTi steel with lower stacking fault energy (SFE) is more susceptible to mechanical twinning and deformation-induced γ ® e martensitic transformation in comparison with CrNiMo steel with higher SFE. The micromechanism of the fracture in hydrogen-assisted surface layers of the steels is compositional, grain-size and hydrogen content dependent characteristic. The present results demonstrate that the steels with UFG structure possess higher resistance to hydrogen embrittlement compared to coarse-grained analogues.
Superplasticity in Ultrafine-Grained Materials.
Authors: Kawasaki Megumi , Langdon Terence G.
Published: April 2019

Superplasticity refers to the ability of a polycrystalline solid to exhibit a high elongation, of at least 400% or more, when testing in tension. The basic characteristics of superplastic flow are now understood and a theoretical model is available to describe the flow process both in conventional superplastic materials where the grain sizes are a few micrometers and in ultrafinegrained materials processed by severe plastic deformation where the grain sizes are in the submicrometer range. This report describes the basic characteristics of superplastic metals, gives examples of flow in ultrafine-grained materials, demonstrates the use of deformation mechanism mapping for providing a visual display of the flow processes and provides a direct comparison with the conventional model for superplastic flow. The report also describes the potential for using nanoindentation to obtain detailed information on the flow properties using only exceptionally small samples.
Mechanism of Stress-Driven Grain Boundary Migration in Nanotwinned Materials
Authors: Skiba N.V.
Published: April 2019

Stress-driven grain boundary (GB) migration in ultrafine-grained materials with nanotwinned structure is theoretically described. In the framework of the theoretical model, the stress-driven high-angle GB migration is accompanied by migration of twin boundaries which adjoin this GB. Energetic characteristics and critical stresses of the GB migration accompanied by the twin boundary migration are calculated.
Annealing-Induced Grain Rotation In Ultrafine-Grained Aluminum Alloy
Authors: Danilenko V. N. , Bachurin D. V. , Nazarov A. A.
Published: April 2019

Results of in situ transmission electron microscopic studies of annealing-induced evolution of grain boundary misorientations in ultrafine-grained aluminum alloy Al-4%Cu-0.5%Zr (wt.%) processed by high pressure torsion are presented. An experimental procedure based on the single reflection technique was applied for the measurements of orientations of individual grains before and after annealing that allowed for determining misorientations between them. The measurements revealed that relaxation processes occurring in non-equilibrium grain boundaries during short-time annealing are accompanied by a change of grain boundary misorientations, grain rotation, grain migration as well as grain growth. Obtained results were compared with theoretical studies considering the kinetics of grain rotation in discrete-dislocation as well as continuum approaches.
Influence of the Support on the Morphology of Co-Sn, Ni-Sn, Co-Ni Nanoparticles Synthesized Through a Borohydride Reduction Method Applying a Template Technique
Authors: Markova I. N. , Piskin M. B. , Zahariev I. Z. , Hristoforou E. , Milanova V. L. , Ivanova D. I. , Fachikov L. B.
Published: April 2019

Intermetallic (Co-Sn, Ni-Sn, Co-Ni) nanoparticles have been synthesized through a borohydride reduction with NaBH4 in aqueous solutions of the chloride salts of Co, Ni, Sn at room temperature using a template technique with a carbon support. As a result nanocomposite materials have been obtained in situ. The ratio of the metallic components has been chosen according the phase diagrams of the relevant binary (Co-Sn, Ni-Sn, Co-Ni) systems: Co:Sn=35:65, Ni:Sn=45:55, Co:Ni=50:50. As carbon supports have been used graphite and carbon powder. To avoid the nanoparticle’s aggregation b-cyclodextrin has been added to the reaction solutions. To study the influence of the supports used on the morphology, specific surface area, elemental and phase composition of the synthesized intermetallic nanoparticles and their carbon nanocomposites SEM, EDS, BET, and XRD investigation techniques have been used. The particle’s morphology varies with the different supports, but in the all cases it is typical for alloyed materials. The nanoparticles are different in shape and size and exhibit a tendency to aggregate. The last-one is due to the unsaturated nanoparticle’s surface and the existing magnetic forces. Regardless of the elemental composition, the nanosized particles are characterized by a relatively high specific surface area (SSA). The Ni-Sn nanoparticle have the largest SSA (80 m2/g), while the Co-Sn particles have the lowest SSA (69 m2/g). The use of a carrier modifies the SSA of the resulting nanocomposites differently depending on the size and shape of the carrier’s particles. The studies conducted on the intermetallic nanoparticles synthesized with various carriers demonstrate that the particle’s morphology, size, and specific surface area for the different supports are suitable for use as catalysts, electrode materials in Li-ion batteries and as magnetic materials for biomedical applications.
A Review on Mechanical and Tribological Properties of Graphite Reinforced Self Lubricating Hybrid Metal Matrix Composites
Authors: Khatkar S. K. , Suri N. M. , Kant S. , Pankaj
Published: April 2019

Hybrid metal matrix composites (HMMC’s) are next generation metal matrix composite materials that have the potential of gratifying recent demands of advanced energy applications in the field of aerospace, automobile and biomedical. The MMC’s have to work at elevated temperature or vacuum environment where lubrication using liquid lubricants is ineffective or difficult to achieve; moreover, liquid lubricants are not environmental friendly, since they releases pollutants into environment. Solid lubricants such as graphite, CNT’s, MoS2and graphene have been widely used as secondary reinforcements to meet such operational needs by fabricating green or environmental friendly self lubricating HMMC’s. This article outlines recent advances in the area of self lubricating HMMC’s reinforced with graphite as secondary reinforcement. The focus of the study was on mechanical and tribological behavior of Aluminum and magnesium based self lubricating HMMC’s. The effect of graphite, different hybrid reinforcements and their strengthening mechanisms are also discussed in detail.
Length Scale Plasticity: A Review from the Perspective of Dislocation Nucleation
Authors: Bagheripoor Mahdi , Klassen Robert
Published: April 2019

Sub-micron and nano-size material systems and components are now regularly being fabricated for use in a wide variety of new applications. These systems exhibit mechanical properties that can be drastically different from their macroscopic counterparts and recently much work has focused on the size effects on the mechanical behaviour of materials. Although the size dependent behaviour has been observed in all of the crystal structures, the governing mechanisms have been found to be different. Different theories have been proposed to describe the size dependent behaviour of metallic samples and the governing mechanisms and it is well known that the surface plays an important role in the plasticity of small scales. Some of the theories indicate the importance of surface in nucleating dislocation and some other ones consider the surface importance as its effect on truncating dislocation loops and activation of internal sources. Moreover, recent studies have revealed that while dislocation based deformation in fcc metals is not very sensitive to temperature, deformation is strongly temperature dependent in bcc metals. The effect of orientation is more clear in the size scale behavior of hcp metals. This review covers recent literature that has focused on uniaxial compression of single crystals at the sub-micron and nanometer scale. The fundamental mechanisms governing the size dependent mechanical behaviour of different crystal structures are described. The effect of fabrication process and current experimental techniques for micro and nano-compression are studied as well.
Synthesis and Properties of Zirconia-Graphene Composite Ceramics: A Brief Review
Authors: Glukharev A. G. , Konakov V. G.
Published: April 2019

The paper summarizes current data on ceramic zirconia-graphene composites. Basic types of graphene-containing additives and the main approaches for composite synthesis are considered. The effect of the additive type and synthesis procedure on the composite structure, mechanical (microhardness and crack resistivity) and electrical (conductivity at room and at elevated temperature) properties of the material is discussed.
EPR, Nexafs Study and Magnetic Properties of Fe-Doped Ferroelectric Ceramics
Authors: Zhuk N. A. , Lutoev V. P. , Makeev B. A. , Chezhina N. V. , Belyy V. A. , Nekipelov S. V.
Published: April 2019

Magnetic susceptibility and EPR of iron-containing solid solutions with layered perovskite-like structure Bi2BaNb2-2xFe2xO9-δ and Bi5Nb3-3xFe3xO15-δ have been studied. The solid solutions Bi2BaNb2-2xFe2xO9-δ as well as iron oxides FeO, Fe2O3, and Fe3O4 were studied by the NEXAFS spectroscopy. The formation of exchange-bound aggregates of Fe(III) atoms with antiferroand ferromagnetic exchange types has been found in the solid solutions. In the ESR spectra of the solid solution samples, the lines with g ≈ 2.0 and g = 4.27 having a weak shoulder at g ~ 8 were attributed to Fe(III) atoms in the octahedral field with strong rhombic distortion.
Demarcating Exercise Intensity Domains in Freestyle Swimming: Is There an Alternative to Incremental Step Test and Beats Below HRmax Method?
Authors: Piatrikova Eva , Sousa Ana C. , Willsmer Nicholas J. , Gonzalez Javier T. , Williams Sean
Published: April 2019

Piatrikova, E, Sousa, AC, Willsmer, NJ, Gonzalez, JT, and Williams, S. Demarcating exercise intensity domains in freestyle swimming: is there an alternative to incremental step test and beats below HRmax method? J Strength Cond Res 34(9): 2575–2584, 2020—Critical power derived from the 3-minute all-out test (3MT) was recently used to estimate the exercise intensity boundaries in competitive cyclists. Considering that physiological testing is challenging in swimming, the purpose of this study was to examine whether critical speed (CS) derived from the 3MT could be used for the same purpose in swimming. The second aim was to assess the accuracy of the 50-40 and 30-20 beats below the maximal (BBM) heart rate method, currently used by swimming coaches to demarcate boundaries between moderate-heavy and heavy-severe exercise, respectively. Thirteen swimmers completed an incremental step test (IST) and 3MT in freestyle to establish speeds at: lactate threshold (LT), lactate turnpoint (LTP), maximum aerobic speed (Smax), and CS. Using linear regression through origin, speeds at LT, LTP, and Smax were predicted at 89, 98, and 104% of CS derived from the 3MT, respectively. There were no significant differences between threshold speeds derived from the IST and 3MT (p > 0.05), and nearly perfect correlations at LT (1.21 ± 0.06; 1.21 ± 0.06 m·s−1; r = 0.92) and LTP (1.33 ± 0.07; 1.33 ± 0.07 m·s−1; r = 0.90), and very large correlations at Smax (1.40 ± 0.06; 1.40 ± 0.07 m·s−1; r = 0.88; all p < 0.0001). Speeds estimated at 50 (1.11 ± 0.08 m·s−1) and 40 BBM (1.17 ± 0.07 m·s−1) were lower compared with LT, and speeds estimated at 30 (1.23 ± 0.07 m·s−1) and 20 BBM (1.29 ± 0.07 m·s−1) were lower compared with LTP and CS (all p < 0.02). The 3MT can therefore be used as an alternative to the IST to estimate exercise intensity boundaries, in practical settings where resources or time might be limited. However, the BBM significantly underestimates speeds at LT, LTP, and CS.
Predictors of Fat Oxidation and Caloric Expenditure With and Without Weighted Vest Running
Authors: Purdom Troy M. , Mermier Christine , Dokladny Karol , Moriarty Terence , Lunsford Leigh , Cole Nathan , Johnson Kelly , Kravitz Len
Published: April 2019

Purdom, TM, Mermier, C, Dokladny, K, Moriarty, T, Lunsford, L, Cole, N, Johnson, K, and Kravitz, L. Predictors of fat oxidation and caloric expenditure with and without weighted vest running. J Strength Cond Res 35(7): 1865–1872, 2021—This study evaluated the effect of weighted vest running (WVR) on fatty acid oxidation (FAox) and caloric expenditure at predesignated steady-state exercise intensities. Seventeen recreationally trained runners (9 men and 8 women) performed 4 separate graded exercise tests (GXTs) separated by at least 24 hours. The first GXT was a V̇o
2max test to establish running velocities (percentage of max) at the prespecified exercise intensities (60, 65, 70, 75, and 80% V̇o
2max). The following randomized WVR trials included a control (no vest), 5% body mass (BM) vest, and 10% BM vest using 3-minute incrementally increasing steady-state stages. Indirect calorimetry was used to measure both FAox (g·min−1) and caloric expenditure (kcal·min−1) at each stage. The ANOVA/ANCOVA analysis revealed that intensity had the largest effect on and FAox (p < 0.001) while WVR had a significant main effect on both caloric expenditure and FAox (p < 0.05). Pairwise comparisons revealed that the 10% BM significantly increased caloric expenditure for all exercise intensities compared with control and 5% BM (except 60% V̇o
2max), while FAox decreased in the 10% BM 70 and 75% V̇o
2max intensities only. Marginal r-squared (

) demonstrate that when sex + fat-free mass (FFM) + fat mass (FM) were included as covariates, sex was a significant predictor of caloric expenditure but was further explained by the large FFM (kg) differences between the sexes significantly influencing caloric expenditure (

= 0.87, p < 0.001). Exercise intensity, body composition (FFM + FM), and external mass placement are relevant considerations for runners looking to maximize FAox and caloric expenditure.
Examining the Accuracy of the Polar A360 Monitor
Authors: Rider Brian C. , Conger Scott A. , Ditzenberger Grace L. , Besteman Summer S. , Bouret Claire M. , Coughlin Adam M.
Published: April 2019

Rider, BC, Conger, SA, Ditzenberger, GL, Besteman, SS, Bouret, CM, and Coughlin, AM. Examining the accuracy of the Polar A360 monitor. J Strength Cond Res 35(8): 2165–2169, 2021—The purpose of this study was to determine the accuracy of the Polar A360 heart rate (HR) monitor during periods of rest, walking/running, and active/passive recovery from exercise. Thirty collegiate athletes (women n = 15 and men n = 15) wore an A360 monitor and a previously validated chest HR monitor (Polar RS400) that served as the criterion measurement across a range of resting and walking/running intensities. First, subjects rested in a supine, seated, and standing position. Next, each subject walked on a treadmill at 1.6 kilometers per hour (kph). Speed was increased by 1.6 kph every 2 minutes until volitional fatigue. Then, subjects walked at 4.8 kph followed by a seated recovery stage. Heart rate was recorded in 30-second increments. Total mean difference in HR readings, percent accuracy, and intraclass correlation coefficient (ICC) analysis established the level of agreement between devices. Bland-Altman plots and a regression were used to examine the agreement between devices. The A360 demonstrated a strong correlation with the RS400 (r
2 = 0.98) across time points. The analysis of variance with repeated measures indicated an overall significant difference (p < 0.001) between devices. The A360 significantly underestimated HR during the 6.4-kph speed only (p < 0.05) (effect size 0.26). The greatest percent accuracy occurred during rest (91%) and recovery (90%). An ICC of 0.98 (SEM: 0.35) demonstrates a strong level of agreement between devices. The A360 is accurate at rest and during various walking and running speeds and thus is a device that can be used with confidence by athletes for specific training purposes. Future research should examine accuracy during weight training and other sport-specific activities.
Load-Power Relationships for High-Speed Knee Extension Exercise
Authors: Chen Ling , Davison Steve W. , Selimovic Ema A. , Mueller Rebecca E. , Beatty Samantha R. , Carter Kathy A. , Parmar Prashant J. , Symons Thorburn B. , Pantalos George M. , Caruso John F.
Published: April 2019

Chen, L, Davison, SW, Selimovic, EA, Mueller, RE, Beatty, SR, Carter, KA, Parmar, PJ, Symons, TB, Pantalos, GM, and Caruso, JF. Load-power relationships for high-speed knee extension exercise. J Strength Cond Res 33(6): 1480–1487, 2019—Seventy subjects did 4 knee extensor workouts with their left legs to assess load-power relationships produced on a high-speed trainer (HST; Newnan, GA, USA). Each workout is composed of 4 sets done on the HST at a different load (1, 4.4, 6.7, 9 kg). A Latin Squares Design determined load sequence per workout. Average power (AP) and peak power (PP) and those same values normalized to body mass (BM) and fat-free mass (AP/BM, PP/BM, AP/FFM, PP/FFM) were each analyzed with 2 (gender) × 4 (load) analysis of variances, with repeated measures for load. We assessed relationships between normalized loads and AP and PP values with correlation coefficients. Average power results revealed a significant interaction, with men > women at 9 kg. Peak power/body mass also yielded an interaction, with women > men at 6.7 and 9 kg. Average power/fat-free mass and PP/FFM each produced interactions, with women > men at 4.4, 6.7, and 9 kg. Correlation coefficients showed significant (r = 0.80–0.82) relationships between normalized loads and AP and PP values. In conclusion, the very low inertial resistance to initiate each repetition on this novel device may in part explain our PP/BM, AP/FFM, PP/FFM results, in which higher values were achieved by women. Our practical applications imply that the low inertial resistance for HST repetitions negates male size and strength advantages typically seen when power is measured.
Biomechanical Comparison of the Reverse Hyperextension Machine and the Hyperextension Exercise
Authors: Lawrence Michael A. , Chin Andrew , Swanson Brian T.
Published: April 2019

Lawrence, MA, Chin, A, and Swanson, BT. Biomechanical comparison of the reverse hyperextension machine and the hyperextension exercise. J Strength Cond Res 33(8): 2053–2056, 2019—The purpose of this study was to compare activation of the erector spinae, gluteus maximus, and biceps femoris muscles, lower back extension moment, and lower extremity range of motion (ROM) between the reverse hyperextension (RHE) and hyperextension (HE) exercises. Motion and muscle activation of the trunk and lower extremity were measured while 20 recreationally active individuals performed 2 sets of 10 repetitions of each exercise. Equivalent loads were used for each exercise. Peak, average, and integrated muscle activity, low back moment, and ROM between the trunk and pelvis and the thigh and trunk were calculated. A Wilcoxon signed-rank test (p = 0.05) revealed significantly greater integrated activity of the biceps femoris and gluteus maximus during the HE exercise. The RHE exercise generated greater peak (+129%), integrated (+63%), and mean (+78%) low back moment as compared to the HE exercise. The RHE resulted in a significantly greater thigh to trunk ROM, 76.6° compared with 64.7°. However, the RHE used less lumbar flexion, 20.4° compared with 31.1° for the HE. The RHE movement profile is preferable because it provides greater hip ROM with less angular stress and equivalent erector spinae activity.
The Role of Distinct Facets of Perfectionism and Sociocultural Idealization of Thinness on Disordered Eating Symptoms
Authors: Habashy Jessica , Culbert Kristen M.
Published: April 2019

Introduction: Perfectionism is a multidimensional personality style implicated in risk for disordered eating (DE), yet the types of perfectionism most predictive of DE and how perfectionistic tendencies lead to the development of DE remains less clear. This study aimed to determine the types of perfectionism most strongly associated with DE and whether perceived pressures for thinness and thin-ideal internalization serve as intervening variables that explain associations between perfectionism and DE.

Methods: An ethnically diverse sample of female college students (n = 154–292) completed well-validated self-report questionnaires assessing overall DE symptoms, perfectionism, and two sociocultural factors: pressures for thinness and thin-ideal internalization.

Results: Only perfectionism constructs encompassed under the “maladaptive evaluative concerns” domain were significantly associated with DE. Double mediation models indicated that heightened pressures for thinness and thin-ideal internalization fully mediate perfectionism-DE associations.

Discussion: Results suggest that disorder-specific risk factors related to idealization of thinness may be important for understanding how a transdiagnostic factor, like perfectionism, results in DE.