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Margienė, Asta, and Simona Ramanauskaitė. "Toward Adaptability of E-Evaluation: Transformation from Tree-Based to Graph-Based Structure." Applied Sciences 11, no. 9 (April 29, 2021): 4082. http://dx.doi.org/10.3390/app11094082.
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The COVID-19 pandemic and quarantine have forced students to use distance learning. Modern information technologies have enabled global e-learning usage but also revealed a lack of personalization and adaptation in the learning process when compared to face-to-face learning. While adaptive e-learning methods exist, their practical application is slow because of the additional time and resources needed to prepare learning material and its logical adaptation. To increase e-learning materials’ usability and decrease the design complexity of automated adaptive students’ work evaluation, we propose several transformations from a competence tree-based structure to a graph-based automated e-evaluation structure. Related works were summarized to highlight existing e-evaluation structures and the need for new transformations. Competence tree-based e-evaluation structure improvements were presented to support the implementation of top-to-bottom and bottom-to-top transformations. Validation of the proposed transformation was executed by analyzing different use-cases and comparing them to the existing graph-to-tree transformation. Research results revealed that the competence tree-based learning material storage is more reusable than graph-based solutions. Competence tree-based learning material can be transformed for different purposes in graph-based e-evaluation solutions. Meanwhile, graph-based learning material transformation to tree-based structure implies material redundancy, and the competence of the tree structure cannot be restored.
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Gorobets, Valery, Ievgen Antypov, Viktor Trokhaniak, and Yurii Bohdan. "Experimental and numerical studies of heat and mass transfer in low-temperature heat accumulator with phase transformations of accumulating material." MATEC Web of Conferences 240 (2018): 01009. http://dx.doi.org/10.1051/matecconf/201824001009.
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Accumulation of thermal energy is produced with the aim of storing at certain times, when there is an overabundance of this energy and its further use in other periods of time when there is a deficit thermal energy. Thermal energy storage may be carried out under heating of any material (water, solid materials etc.) or by using the phase or chemical transformation of the material (melting and crystallization processes, direct and reverse chemical reaction). Thermal accumulators with phase or chemical transformations are allowed to concentrate a large amount of energy in a relatively small volume of accumulating material. In this paper an experimental study and numerical modeling of heat and mass transfer in the heat accumulator during phase transformations of the accumulating material are presented. The experimental plant consists of a chamber filled with paraffin. In experimental studies, the changes of the temperature distribution in heat accumulating material and tube bundles have investigated. Numerical simulation of melting and solidification of heat accumulating material during the heated and cooled of tube bundles were performed. As the results of research, the basic laws of melting and crystallization processes in heat accumulator during phase transformations of heat accumulating material were determined.
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Antoni, Grégory. "Effects of ThermoMechanical Coupling in Tribological Surface Transformations: A One-Dimensional Modelling Including Irreversible Solid-Solid Phase Transformations and Classical Plasticity." Journal of Materials 2013 (April 28, 2013): 1–7. http://dx.doi.org/10.1155/2013/892050.
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Under compressive loads combined with friction, some materials undergo Tribological Surface Transformations (TSTs) on the surface of the loaded parts and in the immediately vicinity, which in the case of metals, are known as irreversible solid-solid phase transformations. During the solid-solid phase transformations occurring under mechanical loads, TRansformation Induced Plasticity (TRIP) processes are generated at much lower stress levels than those associated with the yield strength of the material in classical plasticity. In order to assess the effects of thermomechanical coupling in these TSTs, a one-dimensional modelling based on irreversible solid-solid phase transformations and classical plasticity is presented and discussed.
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Weng, Zi-Hua. "Basic postulates of some coordinate transformations within material media." AIP Advances 12, no. 12 (December 1, 2022): 125016. http://dx.doi.org/10.1063/5.0132194.
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This paper aims to explore the physical quantities of several invariants, including the basic postulates of some types of crucial coordinate transformations, conservation laws, and continuity equations, in the electromagnetic and gravitational fields. Maxwell first utilized quaternions to describe the electromagnetic theory. Subsequent scholars make use of octonions to study the physical properties of electromagnetic and gravitational fields simultaneously, including the octonion field strength, field source, angular momentum, torque, and force. When an octonion coordinate system transforms rotationally, the scalar part of one octonion will remain unchanged, although the vector part of the octonion may alter. In the octonion space [Formula: see text], some invariants can be derived from this octonion property. A part of these invariants can be selected as the basic postulates of Galilean transformation or Lorentz transformation. Similarly, several invariants can be derived from the octonion property in the transformed octonion space [Formula: see text], and the invariants can be chosen as the basic postulates of a few new types of coordinate transformations. Furthermore, the combination of invariants in the octonion spaces can be applied as the basic postulates of some new coordinate transformations, relevant to the norm of physical quantities. Through the analysis, it is easy to find that each conserved quantity has its preconditions from the perspective of octonion spaces. This is helpful to deepen the further understanding of the physical properties of conservation laws and other invariants.
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Cottam, Ryan, Vladimir Luzin, Kevin Thorogood, Yat C. Wong, and Milan Brandt. "The Role of Metallurgical Solid State Phase Transformations on the Formation of Residual Stress in Laser Cladding and Heating." Materials Science Forum 777 (February 2014): 19–24. http://dx.doi.org/10.4028/www.scientific.net/msf.777.19.
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There are two major types of solid state phase transformations in metallic materials; the formation of second phase particles during heat treatments, and the transformation of the matrix from one crystalline packing arrangement to another during either heating or cooling. These transformations change the spacing between adjacent atoms and can thus influence the residual stress levels formed. The heating and cooling cycles of materials processing operations using lasers such as cladding and melting/heating, can induce phase transformations depending on the character of the material being processed. This paper compares the effects of the different phase transformations and also the influence of the type of laser processing on the final residual stress formed. The comparisons are made between laser clad AA7075, laser clad Ti-6Al-4V and laser melted nickel-aluminium bronze using neutron diffraction and the contour method of measuring residual stress.
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Waimann, Johanna, Philipp Junker, and Klaus Hackl. "A variational material model for transformation-induced plasticity in polycrystalline steels." Journal of the Mechanical Behavior of Materials 24, no. 5-6 (December 1, 2015): 153–59. http://dx.doi.org/10.1515/jmbm-2015-0022.
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AbstractThis work presents a variational material model for transformation-induced plasticity in steels. We will use the principle of the minimum of the dissipation potential to develop a coupled material model for plastic deformations and phase transformations that simultaneously accounts for the hardening effects that play an important role. We will use a polycrystalline approach and introduce a combined Voigt/Reuß bound and a coupled ansatz for the dissipation functional to model the simultaneous effects of plastic deformations and phase transformations. Finally, we will present the first numerical results for a tension/compression test.
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Jensen, Casper Bruun. "Material Itineraries: Southeast Asian Urban Transformations." East Asian Science, Technology and Society: An International Journal 15, no. 2 (April 3, 2021): 124–34. http://dx.doi.org/10.1080/18752160.2021.1917840.
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Gubin, Sergey P. "Triad matter –- substance – material." Radioelectronics. Nanosystems. Information Technologies. 14, no. 3 (September 19, 2022): 341–48. http://dx.doi.org/10.17725/rensit.2022.14.341.
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An essay on the philosophical aspects of materials science in the absence of a modern philosophical category "material" is presented. The features of the categories "substance" and "material" are considered, which express the distinctive properties of the corresponding objects of nature - the formlessness of the substance and the proper form of the material, the size of the particles of the substance and the structural form of the material. Substance-material mutual transformations, their energy aspects, a certain conditionality of the substance-material boundary, and adequate filling of the corresponding categories are analyzed. Also noted is the virtual reality of the elements of the structure of matter and material, its dependence on the distorting influence of experimental tools. The prospects of translating the regularities of matter-material transformation to extraterrestrial objects are noted.
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Ding, Zi Shan, Bei Zhi Li, Pan Zou, and Steven Y. Liang. "Material Phase Transformation during Grinding." Advanced Materials Research 1052 (October 2014): 503–8. http://dx.doi.org/10.4028/www.scientific.net/amr.1052.503.
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This study investigated the process parameters effect on the phase transformation during grinding by experimental validation and correlation analyses. The quantitative material phase link to the kinetics of diffusion-controlled as well as diffusionless transformations in different strain rate and contact zone temperature by examining process parameters is presented. Based upon the mechanical physics-based modeling and prediction for the volume fraction of phase transformation in continuous heating under anisothermal conditions, the correlation between volume fractions of phase in sequential segmented isothermal processes, and grinding process parameters characteristic are developed. In validation of the correlation, a series of maraging steel 250 grinding experiments, XRD measurements, and correlation analyses were pursued. Certain linear correlations between the cutting parameters and the phase transformation were calculated by using the correlation coefficient and the affected degree of cutting parameter, temperature, and strain rate was evaluated by applying partial relation coefficient analysis method. It is practical to alter the part material properties through the phase transformation with process parameters optimal control.
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Hubbell, Jeffrey A. "In Situ Material Transformations in Tissue Engineering." MRS Bulletin 21, no. 11 (November 1996): 33–35. http://dx.doi.org/10.1557/s0883769400031821.
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Novel applications exist for biomedical materials that can undergo transitions in material properties in situ—that is, at the site of implantation in the body. Such transitions in polymeric biomaterials can be accomplished by crosslinking a material in situ, by heating or cooling to induce thermal transitions, and by precipitating polymer from solution in situ. This article will point out the need for materials that can be induced to undergo such transitions in situ and will describe selected tissue-engineering approaches that have been employed for this purpose.Delivering materials to the body in one form and utilizing them in another form after a transition at the site of implantation has, generally speaking, two potential advantages: (1) the ability to match the morphology of a material implant to a complex tissue shape and (2) the ability to deliver a large device through a small hole in the body. With respect to the former motivation, tissue shapes in the body have an enormous range of complexity: a region of a blood vessel—for example with a curved central axis, a diameter that varies along the length, an eccentric diseased plaque, and numerous side branches. One could develop a variety of implant shapes—arterial stents in this example (for use in structurally supporting arteries after balloon angioplasty, thereby creating a larger cross section for blood flow above the diseased plaque)—and then select the most appropriate implant shape after detailed imaging of the tissue site. One can alternatively attempt to employ some material transformation to deliver a precursor to the final shape of the implant, utilizing the tissue shape to obtain the proper final implant morphology. With regard to the second motivation, it may be desirable to deliver a large object through a small hole, utilizing material transformations. Advances in surgery have focused on manipulating (cutting, coagulating, suturing, stapling) large tissue sites through small holes in the body via minimally invasive surgery. Using such approaches, it has become possible to perform many complex surgical procedures in the joints, abdominopelvic cavity, thoracic cavity, and nasal sinuses, for example, using surgical instruments that are manipulated through surgical access holes less than 1 cm in diameter. Even procedures as complex as coronary-artery bypass surgery have been performed in this way. It still remains generally impossible however to implant devices in the body through such holes unless these implants are very small. If such devices were for example able to be delivered as liquids and then shaped into devices at the implant site, such minimally invasive surgical-device placement could be envisioned.
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Burow, Juri, Egor Prokofiev, Christoph Somsen, Jan Frenzel, Ruslan Valiev, and Gunther F. Eggeler. "Martensitic Transformations and Functional Stability in Ultra-Fine Grained NiTi Shape Memory Alloys." Materials Science Forum 584-586 (June 2008): 852–57. http://dx.doi.org/10.4028/www.scientific.net/msf.584-586.852.
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Martensitic transformations in NiTi shape memory alloys (SMAs) strongly depend on the microstructure. In the present work, we investigate how martensitic transformations are affected by various types of ultra-fine grained (UFG) microstructures resulting from various processing routes. NiTi SMAs with UFG microstructures were obtained by equal channel angular pressing, high pressure torsion, wire drawing and subsequent annealing treatments. The resulting material states were characterized by transmission electron microscopy and differential scanning calorimetry (DSC). The three thermomechanical processing routes yield microstructures which significantly differ in terms of grain size and related DSC chart features. While the initial coarse grained material shows a well defined one-step martensitic transformation on cooling, two-step transformations were found for all UFG material states. The functional stability of the various UFG microstructures was evaluated by thermal cycling. It was found that UFG NiTi alloys show a significantly higher stability. In the present work, we also provide preliminary results on the effect of grain size on the undercooling required to transform the material into B19’ and on the related heat of transformation.
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Esmonde, Harry. "Fractal and Fractional Derivative Modelling of Material Phase Change." Fractal and Fractional 4, no. 3 (September 14, 2020): 46. http://dx.doi.org/10.3390/fractalfract4030046.
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An iterative approach is taken to develop a fractal topology that can describe the material structure of phase changing materials. Transfer functions and frequency response functions based on fractional calculus are used to describe this topology and then applied to model phase transformations in liquid/solid transitions in physical processes. Three types of transformation are tested experimentally, whipping of cream (rheopexy), solidification of gelatine and melting of ethyl vinyl acetate (EVA). A liquid-type model is used throughout the cream whipping process while liquid and solid models are required for gelatine and EVA to capture the yield characteristic of these materials.
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Antoni, Grégory, Frédéric Lebon, and Thierry Désoyer. "Return Mapping Algorithms (RMAs) for Two-Yield Surface Thermoviscoplastic Models Using the Consistent Tangent Operator." International Journal of Nonlinear Sciences and Numerical Simulation 19, no. 7-8 (December 19, 2018): 681–97. http://dx.doi.org/10.1515/ijnsns-2017-0073.
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AbstractThe return mapping algorithms (RMAs) presented here are designed for use with pressure-dependent thermoviscoplastic constitutive models involving irreversible effects associated with solid–solid phase transformations. During the volume solid–solid phase transformations occurring under mechanical loads, an “anomalous” plasticity, the so-called “TRansformation Induced Plasticity” (TRIP), is generated at much lower stress levels than those related to the yield stress of the material in the context of the classical plasticity. TRIP mechanisms are superimposed on the classical plasticity which is liable to occur in the case of metallic materials. Based on a non-standard generalized material framework, two different models are presented in which an “associative” plastic flow is introduced in the context of classical plasticity and a “non-associative” flow rule in the context of TRIP-like plasticity. In this paper, a complete algorithmic treatment of these two rate-dependent constitutive models is therefore proposed with the associated consistent tangent operator for dealing the quasi-surface irreversible solid–solid transformations which can appear in metal alloys during specific thermomechanical solicitations. The predictive abilities of the presented numerical procedure for modelling this kind of the irreversible solid–solid transformations involving two plasticity processes are tested and assessed by performing a two-dimensional finite-element analysis on some numerical examples.
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de Bortoli, Daniel, Fauzan Adziman, Eduardo A. de Souza Neto, and Francisco M. Andrade Pires. "Constitutive modelling of mechanically induced martensitic transformations." Engineering Computations 35, no. 2 (April 16, 2018): 772–99. http://dx.doi.org/10.1108/ec-03-2017-0087.
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Purpose The purpose of this work is to apply a recently proposed constitutive model for mechanically induced martensitic transformations to the prediction of transformation loci. Additionally, this study aims to elucidate if a stress-assisted criterion can account for transformations in the so-called strain-induced regime. Design/methodology/approach The model is derived by generalising the stress-based criterion of Patel and Cohen (1953), relying on lattice information obtained using the Phenomenological Theory of Martensite Crystallography. Transformation multipliers (cf. plastic multipliers) are introduced, from which the martensite volume fraction evolution ensues. The associated transformation functions provide a variant selection mechanism. Austenite plasticity follows a classical single crystal formulation, to account for transformations in the strain-induced regime. The resulting model is incorporated into a fully implicit RVE-based computational homogenisation finite element code. Findings Results show good agreement with experimental data for a meta-stable austenitic stainless steel. In particular, the transformation locus is well reproduced, even in a material with considerable slip plasticity at the martensite onset, corroborating the hypothesis that an energy-based criterion can account for transformations in both stress-assisted and strain-induced regimes. Originality/value A recently developed constitutive model for mechanically induced martensitic transformations is further assessed and validated. Its formulation is fundamentally based on a physical metallurgical mechanism and derived in a thermodynamically consistent way, inheriting a consistent mechanical dissipation. This model draws on a reduced number of phenomenological elements and is a step towards the fully predictive modelling of materials that exhibit such phenomena.
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Miryuk, O. A. "Thermal Transformations of the Technogenic Component of the Cement Raw Material Mixture." Ecology and Industry of Russia 24, no. 4 (April 24, 2020): 36–41. http://dx.doi.org/10.18412/1816-0395-2020-4-36-41.
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There are presented the results of physicochemical studies of the composition and thermal transformations og large-tonnage wastes of beneficiation of scarnified-magnetite ores from Kazakhstan. To determine the composition of materials and thermal transformations, the following methods were used: X-ray phase analysis, differential-thermal analysis, Mцssbauer and infrared spectroscopy. There was revealed the stepwise nature of the transformation of anthropogenic material during roasting, due to polymineral composition of ore beneficiation. It has been established that the chemical-mineral characteristics of natural silicates determine the formation processes and properties of clinker phases. An integrated approach to the study of technogenic raw materials allowed not only to substantiate the possibility and expedience of using scarnified-magnetite ore beneficiation wastes in cement production, but also to determine the preference for the phase composition of cement clinker. Research result from the basis for the development of low-energy cement clinkers with a high content of belite phase.
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Urzhumov, Yaroslav, Fabrizia Ghezzo, John Hunt, and David R. Smith. "Acoustic cloaking transformations from attainable material properties." New Journal of Physics 12, no. 7 (July 12, 2010): 073014. http://dx.doi.org/10.1088/1367-2630/12/7/073014.
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Eremets, M., I. Trojan, and S. Medvedev. "Phase transformations in silane – hydrogen-dominant material." Acta Crystallographica Section A Foundations of Crystallography 64, a1 (August 23, 2008): C100. http://dx.doi.org/10.1107/s0108767308096803.
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Correa, David, Athina Papadopoulou, Christophe Guberan, Nynika Jhaveri, Steffen Reichert, Achim Menges, and Skylar Tibbits. "3D-Printed Wood: Programming Hygroscopic Material Transformations." 3D Printing and Additive Manufacturing 2, no. 3 (September 2015): 106–16. http://dx.doi.org/10.1089/3dp.2015.0022.
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Chen, Chunlin, Deqiang Yin, Takeharu Kato, Takashi Taniguchi, Kenji Watanabe, Xiuliang Ma, Hengqiang Ye, and Yuichi Ikuhara. "Stabilizing the metastable superhard material wurtzite boron nitride by three-dimensional networks of planar defects." Proceedings of the National Academy of Sciences 116, no. 23 (May 17, 2019): 11181–86. http://dx.doi.org/10.1073/pnas.1902820116.
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Wurtzite boron nitride (w-BN) is a metastable superhard material that is a high-pressure polymorph of BN. Clarifying how the metastable high-pressure material can be stabilized at atmospheric pressure is a challenging issue of fundamental scientific importance and promising technological value. Here, we fabricate millimeter-size w-BN bulk crystals via the hexagonal-to-wurtzite phase transformation at high pressure and high temperature. By combining transmission electron microscopy and ab initio molecular dynamics simulations, we reveal a stabilization mechanism for w-BN, i.e., the metastable high-pressure phase can be stabilized by 3D networks of planar defects which are constructed by a high density of intersecting (0001) stacking faults and {101¯0} inversion domain boundaries. The 3D networks of planar defects segment the w-BN bulk crystal into numerous nanometer-size prismatic domains with the reverse crystallographic polarities. Our findings unambiguously demonstrate the retarding effect of crystal defects on the phase transformations of metastable materials, which is in contrast to the common knowledge that the crystal defects in materials will facilitate the occurrence of phase transformations.
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Koroni, Cyrus, Tristan Olsen, Janelle P. Wharry, and Hui Xiong. "Irradiation-Induced Amorphous-to-Crystalline Phase Transformations in Ceramic Materials." Materials 15, no. 17 (August 27, 2022): 5924. http://dx.doi.org/10.3390/ma15175924.
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Amorphous ceramics are a unique class of materials with unusual properties and functionalities. While these materials are known to crystallize when subjected to thermal annealing, they have sometimes been observed to crystallize athermally when exposed to extreme irradiation environments. Because irradiation is almost universally understood to introduce disorder into materials, these observations of irradiation-induced ordering or crystallization are unusual and may partially explain the limited research into this phenomenon. However, the archival literature presents a growing body of evidence of these irradiation-induced amorphous-to-crystalline (a-to-c) phase transformations in ceramics. In this perspective, the summary and review of examples from the literature of irradiation-induced a-to-c transformations for various classifications of ceramics are provided. This work will highlight irradiation conditions and material parameters that appear most influential for activating a-to-c transformations, identify trends, examine possible mechanisms, and discuss the impact of a-to-c transformations on material properties. Finally, future research directions that will enable researchers to harness a-to-c transformations to tailor materials behaviors will be provided.
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Schmidt, Ina. "A Phenomenological Model for Superelastic NiTi Wires Based on Plasticity With Focus on Strain-Rate Dependency Caused by Temperature." Journal of Engineering Materials and Technology 128, no. 3 (March 3, 2006): 279–84. http://dx.doi.org/10.1115/1.2204940.
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A simple one-dimensional model has been developed to illustrate methods to account for transformation bands in plasticity-based models. Austenite-martensite and martensite-austenite transformations are described by two transformation surfaces in analogy to yield surfaces in plasticity theory. The strain-rate dependence of the material behavior is caused solely by the latent heat of the transformations. Optical and thermographical experiments have been carried out to clarify the dependence of the transformation bands on the distribution of latent heat and therefore on the thermomechanical behavior.
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Joosten, Martina M. "Numerical Analysis of the Effect of Phase Transformation on Residual Stresses in an Autogenous Beam Edge Weld." Materials Science Forum 768-769 (September 2013): 652–59. http://dx.doi.org/10.4028/www.scientific.net/msf.768-769.652.
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This paper presents the numerical analysis of phase proportions and residual stresses in an autogenous beam edge weld. The thin beam was welded running a heat source along its longer edge using a TIG process. There is no addition of any material so the focus of modelling the process could be concentrated on the thermal analysis and the phase transformations. Temperature dependent material properties and a continuous cooling transformation (CCT) diagram of the base material were provided. The simulations took into account metallurgical effects and used a Goldak-type heat source. Simulations with and without phase transformations were carried out, in order to analyse the effect on the predicted residual stress.
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Issers, Oxana. "Potential of Transformations in Polycode Internet Meme Within the Event-Related Context of 2020." Vestnik Volgogradskogo gosudarstvennogo universiteta. Serija 2. Jazykoznanije, no. 2 (June 2021): 26–41. http://dx.doi.org/10.15688/jvolsu2.2021.2.3.
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The article deals with a specific polycode text that functions in the field of virtual communication – Internet meme. The focus is on its regular transformations. Considering possible methodological approaches to the analysis of this phenomenon, the author comes to the conclusion about the efficiency of using the methodology of intertext linguistic theory. The essential characteristic of a meme is its transformational potential, which allows to create new meanings and use this communication unit in a wide range of relevant contexts. The polycode structure of a meme determines the spectrum of its potential transformations by changing the verbal and visual elements. The material of observations was one of the most popular memes of 2020 – "Get up, Natasha, we dropped everything". The author identifies 8 meme transformations, which can be considered as regular: development of the visuals with the addition of a verbal element; contraction of the visuals with the same verbal element / transformation of the verbal element; the reframing of the context; pragmatic transformation; intertextual transformation, including the effect of meta-communication; reduction of the image with the same visual markers; reframing with the change of verbal and visual elements; adaptation of the meme in the media texts. The latter transformation indicates the successful inclusion of the Internet meme as a communication element of network coverse in modern discursive practices.
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Bragan, Ken. "Transformations of Narcissism." Australian & New Zealand Journal of Psychiatry 23, no. 2 (June 1989): 207–11. http://dx.doi.org/10.3109/00048678909062137.
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The self's contrary needs for separateness and for belonging are introduced as a significant polarity in the developmental process, and one which narcissistic persons have failed to resolve in a particular way resulting in a sense of self-distinction but with increasing alienation. Clinical material and material from literature are used to demonstrate this, as well as to raise the possibility that transformations of narcissism sometimes can occur quite quickly. The theoretical implications of this possibility are considered and Jungian ideas put forward as a possible explanation. Finally, brief consideration is given to the practical consequences for therapy that could follow if this understanding has some validity.
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Carmona, José A., Carlos Rodríguez-Franco, Rosario Fernández, Valentín Hornillos, and José M. Lassaletta. "Atroposelective transformation of axially chiral (hetero)biaryls. From desymmetrization to modern resolution strategies." Chemical Society Reviews 50, no. 5 (2021): 2968–83. http://dx.doi.org/10.1039/d0cs00870b.
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Atroposelective transformations of (hetero)biaryls are classified into desymmetrization, kinetic resolution, dynamic kinetic resolution, and dynamic kinetic asymmetric transformation depending on the nature and behavior of the starting material.
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Alipour Skandani, A., R. Ctvrtlik, and M. Al-Haik. "A Novel In-Situ Nanoindentation Characterization of Phase Transforming Materials." MRS Proceedings 1754 (2015): 19–24. http://dx.doi.org/10.1557/opl.2015.198.
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ABSTRACTMaterials with different allotropes can undergo one or more phase transformations based on the changes in the thermodynamic states. Each phase is stable in a certain temperature/pressure range and can possess different physical and mechanical properties compared to the other phases. The majority of material characterizations have been carried out for materials under equilibrium conditions where the material is stabilized in a certain phase and a lesser portion is devoted for onset of transformation. Alternatively, in situ measurements can be utilized to characterize materials while undergoing phase transformation. However, most of the in situ methods are aimed at measuring the physical properties such as dielectric constant, thermal/electrical conductivity and optical properties. Changes in material dimensions associated with phase transformation, makes direct measurement of the mechanical properties very challenging if not impossible. In this study a novel non-isothermal nanoindentation technique is introduced to directly measure the mechanical properties such as stiffness and creep compliance of a material at the phase transformation point. Single crystal ferroelectric triglycine sulfate (TGS) was synthetized and tested with this method using a temperature controlled nanoindentation instrument. The results reveal that the material, at the transformation point, exhibits structural instabilities such as negative stiffness and negative creep compliance which is in agreement with the findings of published works on the composites with ferroelectric inclusions.
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Schmidt, Filipp. "The Art of Shaping Materials." Art and Perception 8, no. 3-4 (October 28, 2019): 407–33. http://dx.doi.org/10.1163/22134913-20191116.
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Material perception — the visual perception of stuff — is an emerging field in vision research. We recognize materials from shape, color and texture features. This paper is a selective review and discussion of how artists have been using shape features to evoke vivid impressions of specific materials and material properties. A number of examples are presented in which visual artists render materials or their transformations, such as soft human skin, runny or viscous fluids, or wrinkled cloth. They achieve this by expressing the telltale shape features of these materials and transformations, often by carving them from a single block of marble or wood. Vision research has just begun to investigate these very shape features, making material perception a prime example of how art can inform science.
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Nikitina, Tatiana G., and Elena I. Rogaleva. "Russian proverbs in linguo-axiological and lexicographic interpretation: Traditions and innovations." Voprosy leksikografii, no. 24 (2022): 70–92. http://dx.doi.org/10.17223/22274200/24/4.
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The aim of the research presented in this article is to develop the concept of a linguo-axiological dictionary representation of proverbs and proverbial concepts in their current state, taking into account various structural and semantic transformations and new axiological components of their meaning. The sources of the material of the study were the paroemiological collections of I. M. Snegirev, I. I. Illustrov, V. I. Dahl, and modern authors; Internet sites; and recordings of live speech of modern native speakers of the Russian language. The development of the lexicographic aspect of the topic was preceded by a comprehensive linguistic analysis of paroemias. The methods of historical-etymological, component, contextual, linguo-axiological analysis reveal their modern semantics and cultural-historical background. The mechanisms of transformations are studied by the method of structural and semantic modeling. The authors’ method of axiologically oriented lexicographic parameterization of the material, developed to solve the research problems, is based on the domestic experience of the dictionary description of paroemias and the authors’ developments in this field. The developed model of the linguo-axiological dictionary representation of paroemias is presented on the material of the proverbial concept “House”, one of the basic concepts of Russian linguaculture. The representation of the paroemiological material in the alphabetical headword dictionary implies the explication of the evaluativeness not only of the original paroemia, but also of its transformations through emotive-evaluative labels, axiologically oriented definitions, and functional-pragmatic commentaries. The transformations of the original proverb are grouped according to structural and semantic models of transformation, which allows us to systematically reflect the transformational potential of the paroemia, to show the dynamics of its formal and conceptual sides, the displacement of its axiological vector. In the thematic dictionary of a new type, the evaluative component of the proverbial concept is reflected by the headings of dictionary macro-entries that convey the general axiological meaning of the group of paroemias. The dictionary macroentries with such axiological headings are grouped within thematic sections in the order from traditional value orientations of linguaculture to new evaluative attitudes represented by new paroemias and proverbial transformations. The emotive and evaluative characteristics of the proverbial material reflecting the new axiologemes allow us to conclude that the neo-paroemias and transformations of traditional proverbs convey the jokingly ironic attitude of nominators to the denial of traditional values rather than their real denial and ridicule. The proposed concept makes a theoretical contribution to the development of problems of linguo-axiological interpretation of paroemias and will find practical implementation in the creating of modern dictionaries of proverbs. The authors declare no conflicts of interests.
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Knitter, Daniel, Jan Piet Brozio, Wolfgang Hamer, Rainer Duttmann, Johannes Müller, and Oliver Nakoinz. "Transformations and Site Locations from a Landscape Archaeological Perspective: The Case of Neolithic Wagrien, Schleswig-Holstein, Germany." Land 8, no. 4 (April 21, 2019): 68. http://dx.doi.org/10.3390/land8040068.
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Societies undergo continuous dynamics and change. By investigating the spatial structure of societal remains and material culture, we tried to get insights into the processes of their landscapes creation. Ritual practices, economic strategies, or the societal structure are stored in the landscape as a form of cultural contextualization. We presumed that changes of these will be strongest during phases of transformation and investigated to which degree transformation processes are mirrored in the spatial structure of material remains. Absolute and relative locations were investigated using data from Neolithic domestic and ritual sites in Wagrien, Schleswig-Holstein, Germany. The results showed that transformations have a different influence on ritual and domestic locations: There are no discernible influences on the choice of relative domestic site locations, in contrast to ritual sites, whose relative location changes as a result of sociocultural transformations. This illustrates the importance of cultural and socioeconomic functions of individual sites and shows that transformations, even when they impact the fundamental structure of a society, do act on different relative and absolute scales and spheres.
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Kryvytskyi, Y. V. "Legal transformation as a component of modern legal development." TRANSFORMATION LEGISLATION OF UKRAINE IN MODERN CONDITIONS DOCTRINAL APPROACHES AND MEASUREMENTS, no. 14 (September 2023): 248–53. http://dx.doi.org/10.33663/2524-017x-2023-14-248-253.
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The article summarizes, expands and substantiates scientific knowledge about legal transformation as a component of modern legal development. The problems of transformations are understood by scientists of various directions and branches of social knowledge, primarily philosophers, political scientists, sociologists, economists and lawyers, since historical progress is directly determined by the ideas of democracy, freedom, free market, law and statehood. The points of view available in the specialized literature regarding the understanding of social transformation, its types, forms, trends and factors are analyzed. Social transformation covers the entire sphere of relations and interests (needs) in society, is the basis of the material and ideological structure on which both theory and practice of human life are based. Social transformation means the process of transformations in society, in particular in the cultural, political, economic and legal spheres. Qualitative and quantitative indicators of these transformations depend on many reasons and factors – internal and external, purposeful and spontaneous, objective and subjective, etc. Based on the study and systematization of transformational issues in legal science, the essence of legal transformation is revealed, under which it is proposed to understand qualitative and quantitative, substantive and formal, progressive and regressive, rational and irrational, regular, random and tendentious transformations of legal matter, legal life,legal reality, legal phenomena and processes under the action, influence, in the context, in the conditions of internal and external, purposeful and spontaneous, objective and subjective causes and factors (globalization, European integration, digitalization, sustainable development, etc.). The prerequisites for determining the common, distinctive and special features of legal transformation and legal reform within the framework of the development of the theory of the latter are outlined. Legal transformation is a component (component) of legal development along with such legal changes as formation, functioning, destruction, and is also carried out in the form of legal evolution, legal revolution, and legal reform. Turning to transformational (transformative) processes in legal reality is intended to continue the scientific search for an optimal, effective model of legal development, initiated by domestic scientists, in fundamentally new realities – in the conditions of war and post-war state reconstruction. Key words: development, social development, legal development, changes, social changes, legal changes, transformation, social transformation, legal transformation, transformation of legislation, transformation of the legal system, reform, social reform, legal reform, theory of legal reform.
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Eremeyev, Victor A., and Violetta Konopińska-Zmysłowska. "On Dynamic Extension of a Local Material Symmetry Group for Micropolar Media." Symmetry 12, no. 10 (October 3, 2020): 1632. http://dx.doi.org/10.3390/sym12101632.
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For micropolar media we present a new definition of the local material symmetry group considering invariant properties of the both kinetic energy and strain energy density under changes of a reference placement. Unlike simple (Cauchy) materials, micropolar media can be characterized through two kinematically independent fields, that are translation vector and orthogonal microrotation tensor. In other words, in micropolar continua we have six degrees of freedom (DOF) that are three DOFs for translations and three DOFs for rotations. So the corresponding kinetic energy density nontrivially depends on linear and angular velocity. Here we define the local material symmetry group as a set of ordered triples of tensors which keep both kinetic energy density and strain energy density unchanged during the related change of a reference placement. The triples were obtained using transformation rules of strain measures and microinertia tensors under replacement of a reference placement. From the physical point of view, the local material symmetry group consists of such density-preserving transformations of a reference placement, that cannot be experimentally detected. So the constitutive relations become invariant under such transformations. Knowing a priori a material’s symmetry, one can establish a simplified form of constitutive relations. In particular, the number of independent arguments in constitutive relations could be significantly reduced.
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Barker, Joshua. "Postscript: Material Itineraries in Southeast Asian Urban Transformations." East Asian Science, Technology and Society: An International Journal 15, no. 2 (April 3, 2021): 233–37. http://dx.doi.org/10.1080/18752160.2021.1917166.
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Suurla, Susanna. "Material Transformations – Making as a Catalyst of Experience." Research in Arts and Education 2018, no. 3 (December 1, 2018): 379–403. http://dx.doi.org/10.54916/rae.118875.
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Marinero, E. E. "Material transformations in semiconductor and magnetic thin films." Applied Surface Science 43, no. 1-4 (December 1989): 117–27. http://dx.doi.org/10.1016/0169-4332(89)90200-6.
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Karlsson, A. M. "On the Mechanical Response in a Thermal Barrier System Due to Martensitic Phase Transformation in the Bond Coat." Journal of Engineering Materials and Technology 125, no. 4 (September 22, 2003): 346–52. http://dx.doi.org/10.1115/1.1605107.
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Recent studies have shown that Pt-aluminide—a common bond coat material in thermal barrier coatings—undergoes martensitic transformations during thermal cycling. The transformations are associated with both large transformation strain and a strain hysteresis, leading to accumulation of a mismatch strain. Thermal barrier systems based on Pt-aluminide bond coats are susceptible to interfacial morphological instabilities. In this study, we investigate how the cyclic martensitic transformation influences the morphology. Two key results are: (i) the morphological instabilities are highly sensitive to the thermo-mechanical properties of the substrate due to the martensitic transformation; (ii) the hysteresis associated with cyclic martensitic transformation cannot drive the morphological instabilities; the strains associated with the formation of the thermally grown oxide do.
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Adiguzel, Osman. "The Role of Twinned and Detwinned Structures on Memory Behaviour of Shape Memory Alloys." Advanced Materials Research 1105 (May 2015): 78–82. http://dx.doi.org/10.4028/www.scientific.net/amr.1105.78.
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Shape memory alloys have a peculiar property to return to a previously defined shape or dimension when they are subjected to variation of temperature. Shape memory effect is facilitated by martensitic transformation governed by changes in the crystalline structure of the material. Martensitic transformations are first order lattice-distorting phase transformations and occur with the cooperative movement of atoms by means of lattice invariant shears in the materials on cooling from high temperature parent phase region. The material cycles between the deformed and original shapes on cooling and heating in reversible shape memory effect. Thermal induced martensite occurs as twinned martensite, and the twinned martensite structures turn into detwinned structures by deforming the material in the martensitic condition. Deformation of shape memory alloys in martensitic state proceeds through a martensite variant reorientation. The deformed material recovers the original shape on first heating over the austenite finish temperature in reversible and irreversible shape memory cases. Meanwhile, the parent phase structure returns to the twinned structure in irreversible shape memory effect on cooling below to martensite finish temperature and to the detwinned structure in reversible shape memory effect. Therefore, the twinning and detwinning processes have great importance in the shape memory behaviour of the materials. Copper based alloys exhibit this property in metastable β-phase region, which has bcc-based structures at high temperature parent phase field, and these structures martensitically turn into layered complex structures with lattice twinning following two ordered reactions on cooling.
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Tachoire, H., and V. Torra. "New trends in differential scanning calorimetry." Canadian Journal of Chemistry 67, no. 6 (June 1, 1989): 983–90. http://dx.doi.org/10.1139/v89-150.
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Recent applications of differential scanning calorimetry in the study of solid–solid transformations are presented. The importance of the deconvolution of the thermograms and of the modelling of the calorimetric equipment is stressed.Investigations of the phase transformations of the martensitic type in shape-memory alloys have made clear the influence of thermomechanical treatment of the material and have evaluated the influence of defects on the dynamics of transformation. A combination of calorimetric and acoustical observations has demonstrated irreversibilities, even in the so-called thermoelastic transitions. Keywords: martensitic transformation, differential scanning calorimetry, entropy production, thermomechanical treatments, acoustic emission.
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Tari, Dariush Ghaffari, Michael J. Worswick, and Usman Ali. "Asymmetric Yield Locus Evolution for HCP Materials: A Continuum Constitutive Modeling Approach." Key Engineering Materials 554-557 (June 2013): 1184–88. http://dx.doi.org/10.4028/www.scientific.net/kem.554-557.1184.
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A continuum-based plasticity approach is considered to model the anisotropic hardening response of hexagonal closed packed (hcp) materials. A Cazacu-Plunkett-Barlat (CPB06) yield surface is modified to create anisotropic hardening in terms of the accumulated plastic strain. The anisotropy and asymmetry parameters are replaced with saturation-type functions and the new modified model is then optimized globally to fit the material response. Furthermore, the effect of the number of linear stress transformations performed on the deviatoric stress tensor is investigated on the capability of the model to capture the response from the experiments. By increasing the number of stress transformations, more flexibility is obtained. However, increasing the number of stress transformations increases the arithmetic calculations involved in the material model. The proposed approach is an effective and time efficient method to create material models with complex evolving tension/compression behavior.
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Ustinova, Daniela V., and Natalia V. Lashtabova. "TRANSLATION TRANSFORMATIONS OF THE LIBRETTO BY N. TATE FOR THE OPERA “DIDO AND AENEAS”." Sovremennye issledovaniya sotsialnykh problem 14, no. 2 (June 30, 2022): 260–70. http://dx.doi.org/10.12731/2077-1770-2022-14-2-260-270.
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The article is devoted to the analysis of translation transformations in musical compositions. Studies in the field of musical translation and opera compositions were considered, difficulties that an interpreter may face were identified. Using the example of N. Tate’s libretto for the opera “Dido and Aeneas”, the texts of the recitative and Dido’s aria were analyzed, as well as the ways of its translation into Russian.
Background. To achieve adequacy in the translation of musical compositions, in particular opera librettos, translators resort to the use of various types of transformations. On basis of the libretto for the opera “Dido and Aeneas”, the analysis of Y. Dimitrin’s translation is carried out.
Purpose. To identify and analyze the translation transformations of Y. Dimitrin’s libretto of the opera “Dido and Aeneas” in comparison with the literal translation.
Materials and methods. The research material was G. Purcell’s opera “Dido and Aeneas” and its translation into Russian. During the analysis of the material, the method of analysis and synthesis of theoretical scientific material on the topic under study, as well as the comparative method were used.
Results. The results of the study proved that due to the difference in the structures of languages, the interpreter faced a number of problems in translation of the recitative and Dido’s aria of the opera. In the process, he was forced to use such translation methods as addition, omission, and integral transformation, which helped him make the Russian version close in meaning and in content.
Practical implications. The results of the research can be used by students of linguistic universities interested in poetic translation, as well as by translators with experience in translating musical compositions, for a profound understanding of the possibilities of using translation transformations.
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Đorđević, Nataša, Slavica Mihajlović, Katarina Pantović-Spajić, Jasmina Lozanović-Šajić, and Mirko Grubišić. "Transformations of mechanochemical activated Na2CO3." Podzemni radovi, no. 41 (2022): 15–21. http://dx.doi.org/10.5937/podrad2241015q.
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During mechanical activation, energy of treated material is increase to a higher level. This can lead to chemical transformation of the activated material. This is the point where we can talk about mechanochemical transformations that have occurred as a result of mechanical activation. The subject of this paper is to monitor mass changes of material after different degrees of activation. One of the substances which is often used in the processes of mechanochemical synthesis is sodium carbonate. The mass changes occurring during the treatment were detected and measured by various methods, depending on the processing environment. The mass increase was attributed to chemisorption of moisture and carbon-dioxide present in air, as a consequence of the sodium carbonate activation. The methods we used were calcimetric chemical analysis. According to obtained results, it was found that activated sodium carbonate is mass-transformed into sodium bicarbonate, whereby these changes are functionally dependent on activation time and the processing atmosphere.
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Pirouz, Pirouz. "Stress-Induced Phase Transformations in SiC." Microscopy and Microanalysis 4, S2 (July 1998): 548–49. http://dx.doi.org/10.1017/s1431927600022868.
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Tetrahedrally co-ordinated materials can undergo stress-induced structural transformations often under invariant plane strain conditions; examples of such transformations are twinning and polytypism. The structure of a tetrahedrally co-ordinated material, XY, may be considered in terms of an assembly of “normal”, Ti’and “twinned” tetrahedra, T'I’all connected to each other at their corners. In some of these materials, e.g. SiC, GaN or CdS, these corner-sharing tetrahedra may be connected to each other in different ways, giving rise to different polytypes. In this paper, a dislocation model for polytypic transformations is discussed and a few examples of stress-induced transformations are illustrated.In general, dislocations in XY polytypes he on basal (0001) planes and are generally dissociated into “leading’ and “trailing” partial dislocations with Burgers vectors b1 and bt’ respectively. There is also good evidence that dissociated dislocations in tetrahedrally-coordinated materials belong to the glide set and move on the slip plane in a dissociated manner.
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Baihaki, Baihaki, Soraya Djamilah, and Ahmad Lazwardi. "DEVELOPING INTERACTIVE LEARNING MEDIA BASED ON ADOBE ANIMATE APPLICATIONS FOR GEOMETRY TRANSFORMATION." Kalamatika: Jurnal Pendidikan Matematika 7, no. 2 (November 30, 2022): 191–206. http://dx.doi.org/10.22236/kalamatika.vol7no2.2022pp191-206.
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Some mathematical material will be challenging to understand without learning media, primarily topics that requires visualization, such as geometric transformations. This study aims to describe the process of developing interactive learning media based on the Adobe Animate application of geometry transformation. It also describes the validity and practicality of the developed learning media. This type of research is research and development. The product developed was an interactive learning media application on geometry transformation material created using Adobe Animate. The development model used was the Multimedia Development Life Cycle (MDLC), consisting of six stages: concept, design, collection of materials, manufacture, testing, and distribution. The research found that the interactive learning media developed were fairly valid (80.12%), with a high level of practicality (4.19). Overall, the learning media developed is feasible to be used in the learning process or as a means of independent learning for students of geometry transformation.
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Liu, Xueyan, Hongwei Li, and Mei Zhan. "A review on the modeling and simulations of solid-state diffusional phase transformations in metals and alloys." Manufacturing Review 5 (2018): 10. http://dx.doi.org/10.1051/mfreview/2018008.
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Solid-state diffusional phase transformations are vital approaches for controlling of the material microstructure and thus tailoring the properties of metals and alloys. To exploit this mean to a full extent, much effort is paid on the reliable and efficient modeling and simulation of the phase transformations. This work gives an overview of the developments in theoretical research of solid-state diffusional phase transformations and the current status of various numerical simulation techniques such as empirical and analytical models, phase field, cellular automaton methods, Monte Carlo models and molecular dynamics methods. In terms of underlying assumptions, physical relevance, implementation and computational efficiency for the simulation of phase transformations, the advantages and disadvantages of each numerical technique are discussed. Finally, trends or future directions of the quantitative simulation of solid-state diffusional phase transformation are provided.
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Mahesh, K. K., and F. M. Braz Fernandes. "Phase transformations in Ni-Ti SMA spring." Journal of Physics: Conference Series 2603, no. 1 (October 1, 2023): 012017. http://dx.doi.org/10.1088/1742-6596/2603/1/012017.
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Abstract Equi-atomic Nickel-Titanium (Ni-Ti) alloy is one of the prominent materials to exhibit two way shape memory effect (TWSME). Since the material by itself can change shape due to variation in temperature, it is also used as an actuator. In the present study, Ni-Ti (49.5at%Ni-Ti) alloy wire is converted into a spring coil with straight portions on either ends by shape setting. Training is provided to the spring coil portion to achieve TWSME. Separate specimens from the spring and straight portions were extracted. Phase transformations were observed in the spring and straight portions during heating and cooling. Phase transformation behaviour of the spring coil and straight portions were studied using differential scanning calorimetry (DSC). The straight portion undergoes simple thermal cycles. But the spring coil portion undergoes thermomechanical (TM) cycles due to change in shapes during heating and cooling. The thermograms obtained show difference in their nature of phase transformations. Discussion focusses on the difference in the thermograms appearing for the specimens from straight and coil portions.
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Bobrova, Maria V. "CONTEMPORARY RURAL ZOONYMICON IN THE DERIVATIONAL ASPECT (on the Material of Zoonyms of One Group of Villages)." Вестник Пермского университета. Российская и зарубежная филология 13, no. 2 (2021): 5–13. http://dx.doi.org/10.17072/2073-6681-2021-2-5-13.
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The article is devoted to the study of zoonyms functioning in the speech of the inhabitants of Troel’ga rural settlement, Kungur district (Perm Krai). Methodologically, animal names are considered in the article in line with the theory of derivation, that is, as a result of dynamic processes at different levels of the language system. It is necessary to distinguish between nicknames that appeared in the course of zoonymic transformations and those that appeared due to transformations of ready-made lexical means (products of pre-zoonymic transformations). We have found that the first ones form as a result of six types of derivation: word-forming derivation (with the formation of words that are absent in the literary language), lexical and word-forming derivation (with the formation of words that are homonymous to the words of the literary language), lexical derivation (with the use of non-derived words that are absent in the literary language: neologisms and barbarisms), lexical-semantic derivation (with the reinterpretation of the semantics of the generating word), lexical-grammatical derivation (with the functional transformation of the generating word), morphological derivation (with the grammatical transformation of the generating word). The words of the second group are included in the zoonymicon through lexical derivation (using derived and non-derived words of the literary language), lexical-semantic derivation (with semantic transformation of all-Russian words), morphological-syntactic derivation (with a change of the part of speech of all-Russian words). Within these types, certain derivational models are implemented, in particular k-suffixation, word convergence based on paronomasia, onymization and transonymization, substantivization, etc. The paper provides a conclusion about a variety of ways of forming modern zoonymicon, about the specificity of some particular derivational models for the given sample.
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Song, Miao, Zexi Lu, and Dongsheng Li. "Phase transformations among TiO2 polymorphs." Nanoscale 12, no. 45 (2020): 23183–90. http://dx.doi.org/10.1039/d0nr06226j.
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Kromm, Arne, Thomas Kannengiesser, and Jens Gibmeier. "In Situ Observation of Phase Transformations during Welding of Low Transformation Temperature Filler Material." Materials Science Forum 638-642 (January 2010): 3769–74. http://dx.doi.org/10.4028/www.scientific.net/msf.638-642.3769.
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Tensile residual stresses introduced by conventional welding processes diminish the crack resistance and the fatigue lifetime of welded components. In order to generate beneficial compressive residual stresses at the surface of a welded component, various post-weld treatment procedures are available, like shot peening, hammering, etc. These post-weld treatments are, however time and cost extensive. An attractive alternative is to generate compressive stresses over the complete weld joint in the course of the welding procedure by means of so-called Low Transformation Temperature (LTT) filler materials. The volume change induced by the transformation affects the residual stresses in the weld and its vicinity. LTT fillers exhibit a relatively low transformation temperature and a positive volume change, resulting in compressive residual stresses in the weld area. In-situ measurements of diffraction profiles during real welding experiments using Gas Tungsten Arc (GTA)-welding process were realized successfully for the first time. Transformation temperatures during heating and subsequent cooling of LTT welding material could be assessed by means of energy dispersive diffraction using high energy synchrotron radiation. The results show that the temperature of martensite start (Ms) is strongly dependent on the content of alloying elements. In addition the results indicate that different phase transformation temperatures are present depending on the welding depth. Additional determination of residual stresses allowed it to pull together time and temperature resolved phase transformations and the resulting phase specific residual stresses. It was shown, that for the evaluation of the residual stress state of LTT welds the coexisting martensitic and austenitic phases have to be taken into account when describing the global stress condition of the respective material in detail.
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Cardone, F., G. Albertini, D. Bassani, G. Cherubini, E. Guerriero, R. Mignani, M. Monti, et al. "Deformed space–time transformations in Mercury." International Journal of Modern Physics B 31, no. 23 (September 14, 2017): 1750168. http://dx.doi.org/10.1142/s0217979217501685.
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A mole of Mercury was suitably treated by ultrasound in order to generate in it the same conditions of local Lorentz invariance violation that were generated in a sonicated cylindrical bar of AISI 304 steel and that are the cause of neutron emission during the sonication. After 3 min, part of the mercury turned into a solid material which turned out to contain isotopes having a different mass (higher and lower) with respect to the isotopes already present in the initial material (mercury). These transformations in the atomic weight without gamma production above the background are brought about during Deformed Space–Time reactions. We present the results of the analyses performed on samples taken from the transformation product. The analyses have been done in two groups, the first one using five different analytical techniques: ICP-OES, XRF, ESEM-EDS, ICP-MS, INAA. In the second group of analyses, we used only two techniques: INAA and ICP-MS. The second group of analyses confirmed the occurring of the transformations in mercury.
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Vazquez, Elena, Benay Gürsoy, and Jose Pinto Duarte. "Formalizing shape-change: Three-dimensional printed shapes and hygroscopic material transformations." International Journal of Architectural Computing 18, no. 1 (December 25, 2019): 67–83. http://dx.doi.org/10.1177/1478077119895216.
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Shape-changing materials have become increasingly popular among architects in designing responsive systems. One of the greatest challenges of designing with these materials is their dynamic nature, which requires architects to design with the fourth dimension, time. This article presents a study that formalizes the shape-changing behavior of three-dimensional printed wood-based composite materials and the rules that serve to compute their shape-change in response to variations in relative humidity. In this research, we first developed custom three-dimensional printing protocols and analyzed the effects of three-dimensional printing parameters on shape-change. We thereafter three-dimensional printed kirigami geometries to amplify hygroscopic material transformation of wood-based composites.
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Serra, M. F., M. S. Conconi, G. Suarez, E. F. Agietti, and N. M. Rendtorff. "Firing transformations of an argentinean calcareous commercial clay." Cerâmica 59, no. 350 (June 2013): 254–61. http://dx.doi.org/10.1590/s0366-69132013000200010.
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Mineralogical transformations caused by firing are usually studied by XRD methods only semi-quantitatively. In this work the original mineral disappearance and the neo-mineralization were evaluated quantitatively. Furthermore an indirect non crystalline phase quantification was performed under 1100 ºC was also carried out using the quartz content as internal standard. This study specifically discusses the behavior of an Argentinean white calcareous earthenware commercial when subjected to traditional ceramic firing, besides the technological importance of this particular material, it acts as a model for other clay based ceramic materials. Materials were subjected to thermal treatments between 700 ºC and 1100 ºC. A preliminary sintering characterization was carried out by contraction and porosity evolution. Simultaneous thermogravimetric and differential thermal analysis (TG-DTA) was carried out to elucidate the actual temperature at which the chemical changes occur. Finally, a quantitative analysis based on the Rietveld refinement of the X-ray diffraction patterns was performed to characterize the crystalline phases present in both the clay and in the materials obtained after different thermal treatments. The actual chemical reactions are proposed. The phases identified after firing at traditional working temperature (1040 ºC) are quartz, plagioclase, and the Spinel type alumino-silicate, accompanied by the non-diffracting un-reacted metakaolin and some amount of amorphous glassy phase. At intermediate temperatures (900 ºC) the presence of gehlenite was also detected. The carbonates (calcite and dolomite) presence and decomposition were also evaluated and demonstrated to determine the sintering characteristics of this material.