Materials science (Materials)

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Materials Science and Engineering Expert Committee (MatSEEC)

Materials Science and Engineering Expert Committee (MatSEEC)

MatSEEC is an independent science-based committee of over 20 experts active in materials science and its applications, materials engineering and technologies and related fields of science and research management. Committee members are nominated by the member institutions and they maintain strong links with their nominating organisations and their respective scientific communities.

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A New Paradigm for Metallic Alloys in Materials Science

A New Paradigm for Metallic Alloys in Materials Science

1) Our understanding of this or that physical phenomenon always changes with time and usually corresponds to the level of experimental technique at the given period. However, some theories and views which formed many years ago (when the modern research methods did not yet exist) persisted to the present. They have so deeply rooted into our minds, that even now, when the experiment does not verify them, we believe that they are the unquestionable truth. For example, we cannot imagine equilibrium phase diagrams without regions of solid solutions at high temperatures, although the latter, from the point of view of thermodynamics, is not an equili- brium phase at any temperature. We cannot imagine the probability of decomposition of a quenched solid solu- tion without its “supersaturation” in the alloying component, which occurs at a decrease of the solution temper- ature. We cannot imagine a heat treatment carried out to obtain a highly dispersed two-phase structure, which will not include a preliminary high-temperature quenching from the solid solution region. The discovery of the phase transition “ordering-phase separation” in alloys makes us look more critically at some ideas existing in Materials Science, and to understand that it is precisely the chemical interactions between dissimilar atoms and their dependence on the transition temperature that are the source of all structural changes in alloys.
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The Materials Science Procedural Text Corpus: Annotating Materials Synthesis Procedures with Shallow Semantic Structures

The Materials Science Procedural Text Corpus: Annotating Materials Synthesis Procedures with Shallow Semantic Structures

planning performance using massive organic re- action knowledge bases as training data (Segler et al., 2018). There are, however, currently no com- prehensive knowledge bases which systematically document the methods by which inorganic materi- als are synthesized (Kim et al., 2017a,b). Despite efforts to standardize the reporting of chemical and materials science data (Murray-Rust and Rzepa, 1999), inorganic materials synthesis procedures continue to reside as natural language descriptions in the text of journal articles. Figure 1 presents an example of such a synthesis procedure. To achieve similar success for inorganic synthesis as has been achieved for organic materials, we must develop new techniques for automatically extracting struc- tured representations of materials synthesis proce- dures from the unstructured narrative in scientific papers (Kim et al., 2017b).
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Materials Science and Engineering Expert Committee (MatSEEC)

Materials Science and Engineering Expert Committee (MatSEEC)

The Review Panel welcomes and commends increasing interaction with industry as illustrated by the latest participation in meetings and discussions. This is also important for the future of materials science in Europe. The Review Panel regrets that the Technology and Knowledge Transfer report has not yet been produced as it addresses critical issues for the economic exploitation of materials science and engineering capacity. Comparison with other parts of the world will be instructive. However, it welcomes and strongly supports early recommendations presented by the Committee Chair: technology validation concept – a very innovative and valuable concept. The membership structure gives constraints, but
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Cathode Lens Mode of the SEM in Materials Science Applications

Cathode Lens Mode of the SEM in Materials Science Applications

The cathode lens (CL) mode of the SEM, employing sample as a cathode of the beam-decelerating electrostatic lens, enables one to preserve the image resolution down to lowest electron energies and in the same time secures an excellent collection efficiency of signal species. In the range of tens and units of eV, new image contrasts become available, based on the quantum mechanical character of scattering and the electron wavelength comparable with inter-atomic distances. However, already in the low keV and hundreds of eV ranges the CL mode has proven itself very efficient in many materials science applications, overcoming some weak points the conventional SEM modes suffer from. Selected material structures are presented as demonstration examples. [doi:10.2320/matertrans.48.944]
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Knowledge and Technology Transfer in Materials Science and Engineering in Europe

Knowledge and Technology Transfer in Materials Science and Engineering in Europe

Advanced Materials is one of the Key Enabling Technologies identified by the European Com- mission1. Together with Advanced Manufacturing it underpins almost all other Key Enabling and Industrial Technologies. The basic science and engineering research that results in the develop- ment of Advanced Materials lies within the field of Materials Science and Engineering (MSE). The transfer of knowledge from basic research into final products and applications in the field of MSE involves certain MSE-typical motifs and specific issues, as well as certain aspects that are special to Europe. In comparison with underlying traditional (or basic) disciplines such as physics, chemistry or biology, MSE involves a range of aspects that are more characteristic of applied science, where rel- evance has equal importance to curiosity in order to drive the research effort and justify expenditure – the defined goals often being a proven innovative technology or indeed a particular product. MSE and the related transfer of knowledge and technology includes consideration of factors such as materials and product life cycles, the abundance of materials, the technical, ecological and economic feasibility of materials engineering and processing, as well as the multidisciplinarity of the ‘background’ knowledge and the efficiency of the academic effort involved. This is even more the case for situations that involve successful validation of technologies and effec- tive transfer of knowledge between academia and industry. The state of knowledge and technology transfer in Europe differs from that of other global players, such as the US, China or Japan. Europe’s cultural diversity gives rise to both positive and
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Materials Science and Engineering in Europe: Challenges and Opportunities

Materials Science and Engineering in Europe: Challenges and Opportunities

Due to their chemical and thermal stability, nar- row pore size distribution, high porosity, high flux, mechanical strength (enabling back flush- ing), microbiological resistance and long lifetime, ceramic membranes are foreseen for filtration purposes in a broad range of industries such as biotechnology and pharmaceutical, dairy, food and beverage, as well as chemical and petrochemi- cal, microelectronics, metal finishing and power generation (Figure 3). Current barriers to their effi- cient implementation in such fields are scaling up and enhanced interaction (information exchange) with industry. Mid-term challenges are more effi- cient (generalised) access to large instruments for improved processing of these materials and for better understanding of their properties, more generally through extended use of analytical tools. This should allow new design of membranes, par- ticularly targeting increased efficiency and at the same time improved recycling. Further progress in this field concerns multiscale modelling and simu- lation with subsequent understanding of transport mechanisms and materials properties. This in turn should contribute towards improved transport properties at low temperature and should confer ceramic membranes with targeted functionalities through optimised formulation design and struc-
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NANOSTATE PHENOMENON IN MATERIALS SCIENCE OF METAL-POLYMERIC SYSTEMS

NANOSTATE PHENOMENON IN MATERIALS SCIENCE OF METAL-POLYMERIC SYSTEMS

Abstract : There were considered the physical, structural and morphological prerequisites for the realization of the nanostate phenomenon of dispersed particles of condensed matter of different composition, nature and technology for production. It was shown the role of the size factor in the occurrence of the nanostate phenomenon due to the change of the energy parameters of the surface layers of particles that contribute to their effective modifying effect on the high-molecular matrix. Physical models of the formation of a particular energy state of dispersed particles and metallic and non-metallic materials substrates, characterized by the presence of local areas ("charge-mosaic") with a long relaxation time are proposed.It was considered practical application of the nanostate phenomenon when creating high-strength and wear-resistant materials based on thermoplastic matrices (PA6, PTFE, PET), consistent lubricant and lubricating oils, tribological and protective coatings for friction units and metalwares used in mechanical engineering, automotive and mining engineering. It was made the examples of the effective use of developed nanocomposite materials in practice.
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Planetary Materials Science and Astrobiology

Planetary Materials Science and Astrobiology

Planetary materials contain signatures of diverse processes in their mineralogy, chemistry, textures and assemblages. The record contained in planetary materials reflects the complex and commonly overprinting relationships between many processes. Discerning what mechanisms have operated to produce the rocks we observe requires first a careful characterization of various properties. These include the chemical and structural makeup of the rocks (that is, the mineralogy and mineral chemistry), the textural relations within and between rocks (petrology) Therefore, the key to how the studies here hold together is also in the methodology and guiding philosophy: understanding what is there (what atoms and how they are arranged, what their interrelationships are) is the first step to unravelling the record of processes stored in planetary materials of all kinds. In this thesis, the tools of mineralogy and geochemistry/cosmochemistry and petrology have been used along with an understanding of the grand-scale astrophysical constraints on planetary formation to interpret diverse planetary materials: terrestrial rocks and meteorites. In this thesis, detailed mineralogical and chemical study of various planetary materials have enabled some new constraints to be placed on asteroidal melting and shock metamorphic processes, the nature of habitable environments in post-impact hydrothermal systems, and the preservation mechanisms of microbial ichnofossils in basaltic glass. These studies all concern the emergence and development of terrestrial planets and habitable environments within them, and the preservation of records of biological activity through deep geologic time. This work therefore represents, in a broad sense, an exploration of the astrobiological implications of planetary materials including likely precursors to terrestrial planets (enstatite chondrites); and important possible planetary habitats including post-impact hydrothermal mineral deposits and their associated weathering assemblages; and the fossilization of records of an ecosystem based on the microbial leaching of seafloor basaltic glass.
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Overview of Borophene as a Potential Candidate in 2D Materials Science for the Energy Applications

Overview of Borophene as a Potential Candidate in 2D Materials Science for the Energy Applications

the UV region [87], therefore, resultant activity was not that great. To overcome this problem we should have semiconductor materials, which as bandgap in the visible region, afterwards many materials have discovered, nevertheless, now it has been great demanding for 2D based materials because of its tunable bandgap so that we could overcome the previous hurdle. Besides, 2D material has high surface area that provides active sites for catalytical activity [88]. The graphene [89,90] is having high catalytical activity and showed for water splitting as well. However, currently, 2D transition metal dichalcogenides have been drastically highlighted for the photocatalytic activity due the long-time stability, tunable bandgap and available active sites for the reaction are existing effectively such WO 3 [91], TiS 2
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Fundamentals of Materials Science and Engineering 5th Edition pdf

Fundamentals of Materials Science and Engineering 5th Edition pdf

For ionic compounds, the situation is more complicated than for metals inasmuch as it is necessary to consider the diffusive motion of two types of ions that have opposite charges. Diffusion in these materials occurs by a vacancy mechanism (Figure 6.3a). And, as we noted in Section 5.3, in order to maintain charge neutrality in an ionic material, the following may be said about vacancies: (1) ion vacancies occur in pairs [as with Schottky defects (Figure 5.3)], (2) they form in nonstoichio- metric compounds (Figure 5.4), and (3) they are created by substitutional impurity ions having different charge states than the host ions (Example Problem 5.2). In any event, associated with the diffusive motion of a single ion is a transference of electrical charge. And in order to maintain localized charge neutrality in the vicinity of this moving ion, it is necessary that another species having an equal and opposite charge accompany the ion’s diffusive motion. Possible charged species include another vacancy, an impurity atom, or an electronic carrier [i.e., a free electron or hole (Section 12.6)]. It follows that the rate of diffusion of these electrically charged couples is limited by the diffusion rate of the slowest moving species.
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Improvement of the Thermoelectric Performance of Pseudogap and Narrow Gap Compounds via Theoretical Calculations

Improvement of the Thermoelectric Performance of Pseudogap and Narrow Gap Compounds via Theoretical Calculations

The author acknowledges Prof. Dr. Kaoru Kimura (The University of Tokyo), Prof. Dr. Jeffrey Snyder (Northwestern University), as well as Dr. Yoshikazu Shinohara, Dr. Yukihiro Isoda, and Dr. Masahiro Goto (National Institute for Materials Science) for their kind support and fruitful discussions. This work is partially supported by KAKENHI grants Nos. 21860021, 23760623, 26709051, and 17H03421 from the Japan Society for the Promotion of Science, the Thermal & Electric Energy Technology Foundation, the Sumitomo Foundation, and the Murata Science Foundation. A synchrotron radiation X-ray diffraction measurement was performed at the BL02B2 beamline of SPring-8 with the approval of the Japan Synchrotron Radiation Research Institute (proposal Nos. 2011A1230 and 2013A1495). This work was partially supported by “Materials research by Information Integration” Initiative (MI 2 I) project of the Support Program for Starting Up Innovation Hub from Japan Science and Technology Agency (JST).
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Significance of value added materials (vams) for modernity and development

Significance of value added materials (vams) for modernity and development

framework for complex hierarchical materials, which enables us to define future scientific hypothese sin the field of biological and synthetic materials and nanotechnology in a systematic way. Such hypothesis must be proved through a unified approach that combines theory, experiment, and simulation, leading to a detailed understanding of how Nature successfully links structure, processes, properties, and functions simultaneously over many length scales, from nano to macro. With the aim of maintaining academic excellence and at the same time reinforcing the capacity to innovate, national funding agencies and European institutions must consider coherent and compatible long­term strategic research plans covering the entire span from exploratory research to market implementation. This should be performed on a well­defined set of the topics presented above and especially on multifunctional and bio­based materials which are still in a nearly development stage and show potential for meeting numerous if not allgr and societal challenges. In addition, the following cross­cutting topics were confirmed as being of critical importance to improve the research process across the material sciences’ board : analytical tools and characterisation methods; combinatorial materials science; data storage and processing tools; simulation ; surface science as an enabling technology; multi functionality; availability of natural resources and recycling.
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Advanced Composite Materials of the Future in Aerospace Engineering

Advanced Composite Materials of the Future in Aerospace Engineering

A380 uses composite materials in its wings as a structural material which is a load carrying structure and helps to enable a 17% lower fuel use per passenger than other comparable aircraft.A highly mechanized production process was established to determine if high material cost could be compensated by increased manufacturing efficiency. Although material costs were 35% greater than a comparable aluminum structure, total manufacturing costs were lowered around 70 to 85%. Robotic assemblies were developed to handle and process materials in an optimal and repeatable fashion.
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Requirements for the transfer of lead-free piezoceramics into application

Requirements for the transfer of lead-free piezoceramics into application

During operation, piezoelectric materials are often exposed to external stresses. For example, internal residual strains can origi- nate from temperature changes, either through self-heating from large- fi eld hysteretic losses or external sources of heat, such as a knock-sensor on a car engine that heats up during the initial engine warm-up phase. As the electro-active elements must be in contact with other components for force transmission, strain in- compatibilities can increase the mechanical stress of the piezo- electric component proportional to its elastic modulus. Stresses can also originate from preloads purposefully applied to decrease cracking, by dynamic electrical loading of actuators, or in piezo- electric fi lms due to various phenomena resulting in mismatch strains, e.g., epitaxial, fi lm densi fi cation, thermal expansion mismatch, etc. The elastic stiffness is an important parameter that helps to determine both the force that can be generated during actuation as well as the resonance frequency of the piezoelectric material. In the case of a clamped fi lm on a substrate, for example, the elastic properties also help determine the effective piezoelec- tric response. Force generation, an important advantage of piezo- electric systems, is also directly related to the system con fi guration, e.g., multilayer actuators have a higher effective stiffness than unimorph bending actuators and can, therefore, transmit more force, albeit with a lower displacement. In resonance applications, such as ultrasonic transduction, the elastic properties play a crucial role in determining the emitter ef fi ciency and the receiver sensi- tivity through the electromechanical coupling factor. An additional consideration is acoustic impedance matching of the piezoelectric to the investigated medium, e.g., body tissue, which allows for a more ef fi cient transduction of acoustic waves. Therefore, changes to the elastic properties during operation are detrimental to ef fi - ciency, requiring accurate knowledge of the elastic properties as a function of temperature to account for this.
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Exploring Funding for Instructional Materials in Secondary Science Classrooms.

Exploring Funding for Instructional Materials in Secondary Science Classrooms.

Bourdieu (1986) argued that capital presents itself in various forms: economic capital, cultural capital, and social capital. Bourdieu (1986) referred to economic capital as being immediately and directly convertible into money and the “root of all other types of capital” (p. 54). He further explained cultural capital exists in embodied, objectified, and institutional forms. Embodied capital is capital that is acquired over time and becomes part of a person, a habitus (Bourdieu, 1986). Bourdieu likened embodied capital to developing a suntan, unable to be immediately undone, or built over time. Embodied science capital includes knowledge of science principles, the ability to design experiments, as well as the ability to plan science lessons (Wilson-Lopez et al., 2018). Bourdieu (1986) labeled objectified capital as being in the form of cultural goods such as “pictures, books, dictionaries, instruments, machines, etc.” (p. 47). Wilson-Lopez et al. (2018) argued “objectified capital is converted to embodied capital when youth acquire knowledge of scientific principles and applications through interactions with science-related objects” (p. 250). Objectified science capital would include teachers interacting with science related goods, such as science kits, and acquiring
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Availability and Adequacy of teaching/learning Materials for the Implementation of Compulsory Science Curriculum in Public Secondary Schools in Bukoba District Council, Tanzania

Availability and Adequacy of teaching/learning Materials for the Implementation of Compulsory Science Curriculum in Public Secondary Schools in Bukoba District Council, Tanzania

were BoM members. Both probability and non-probability sampling procedures were employed to sample target groups. To ensure proportionality in sampling schools, the researchers used stratified sampling technique to sample schools from the four political divisions of BDC namely: Bugabo, Katerero, Kyamutwara and Rubale. Thus, it was possible to apply the method of proportional allocation which guarantees the presence of key subgroups within the sample thereby warranting reliable and detailed information (Kothari, 2004). Other categories of respondents were sampled as summarised in Table 1 and explained in the following paragraphs. As shown in Table 1, tenheads of school and 10 Heads of Science Department of the sampled schools were automatically included in the study. The study used simple random sampling techniques to select science teachers. From the ten sampled schools, teachers for biology, chemistry and physics in Form III were selected for the study (one teacher for each science subject; three teachers from each selected school). Form III students were purposively sampled to participate in the study because they had ample experience in the school and were at ease to respond to the study’s questionnaires. Conscious of gender, researchers used stratified random sampling procedures to sample individual students. In each sampled school, a total number of 26 students from Form III was identified. Half of the number was composed of females and another half of males. Simple random sampling techniques were employed to determine individual participants from each gender group. Eventually, a total number of 211 sampled students was obtained for the study. Ten parents from the BoM of the sampled schools were included in the study. Simple random sampling procedure was used to determine individual parents from the schools’ BoM. Purposive sampling technique was used to sample the DEOSS. His role in the planning, supervising and managing education in the area qualified him to be a reliable source of information for the study. He was selected on the basis that he was the only Education Officer for Secondary Schools in BDC.
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Science Question Answering using Instructional Materials

Science Question Answering using Instructional Materials

Alignment is a common technique in many NLP applications such as MT (Blunsom and Cohn, 2006), RTE (Sammons et al., 2009; MacCartney et al., 2008; Yao et al., 2013; Sultan et al., 2014), QA (Berant et al., 2013; Yih et al., 2013; Yao and Van Durme, 2014; Sachan et al., 2015), etc. Yet, there are three key differences between our approach and alignment based approaches for QA in the literature: (i) We incorporate the curriculum hierarchy (i.e. the book, chapter, section bifurca- tion) into the latent structure. This helps us jointly learn the retrieval and answer selection modules of a QA system. Retrieval and answer selection are usually designed as isolated or loosely connected components in QA systems (Ferrucci, 2012) lead- ing to loss in performance – our approach mit- igates this shortcoming. (ii) Modern textbooks typically provide a set of review questions after each section to help students understand the ma- terial better. We make use of these review prob- lems to further improve our model. These re- view problems have additional value as part of the latent structure is known for these questions. (ii) We utilize domain-specific knowledge sources such as study guides, science dictionaries or semi- structured knowledge tables within our model.
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Magnetic anisotropy and phase transitions in single-crystal Tb5(Si2.2Ge1.8)

Magnetic anisotropy and phase transitions in single-crystal Tb5(Si2.2Ge1.8)

This research was supported by the U.S. Department of Energy, Office of Science 共 OS 兲 , Office of Basic Energy Sci- ences 共 BES 兲 , and Materials Sciences Division. Ames Labo- ratory is operated for the U.S. Department of Energy by Iowa State University under Contract No. W-7405-ENG-82.

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The Effect of Annealing Temperature Change on Carbon Nano Tube Absorption and Refractive Index When Doped With TiO2, CuO, ZnO and MgO

The Effect of Annealing Temperature Change on Carbon Nano Tube Absorption and Refractive Index When Doped With TiO2, CuO, ZnO and MgO

molecular electronics, synthetic bio molecular motors, DNA-based self-assembly, and manipulation of individual atoms via a scanning tunneling microscope, nanotechnology has become the principal focus of a growing cadre of scientists and engineers and has captured the attention and imagination of the general public. This field is defined primarily by a unit of length, the nanometer at which lies the ultimate control over the form and function of matter. Indeed, since the types of atoms and their fundamental properties are limited by the laws of quantum physics, the smallest scale at which we have the freedom to exercise our creativity is in the combination of different numbers and types of atoms used to fabricate new forms of matter. This is the arena of nanotechnology: to build materials and devices with control down to the level of individual atoms and molecules. Such capabilities result in properties and performance far superior to conventional technologies and, in some cases, allow access to entirely new phenomena only available at such scales[ 1, 2].The rapid growth of the field in the past two decades has been enabled by the sustained advances in the fabrication and characterization of increasingly smaller structures.
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