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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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Knowledge and Technology Transfer in Materials Science and Engineering in Europe

Knowledge and Technology Transfer in Materials Science and Engineering in Europe

Historically, Materials Science and Engineering (MSE) emerged as an interdisciplinary field with its roots in several traditional disciplines, such as phys- ics, chemistry, biology, mathematics and mechanical engineering. MSE integrates concepts or methods that may have been originally developed by these disciplines, and applies them to the design of new materials, materials systems and, ultimately, new products. MSE-based research and development seeks new concepts and methods to character- ise and tailor materials properties, and to provide engineering solutions for the most appropriate mate- rials systems to meet predefined specifications. This includes identifying the most appropriate processes for fabrication and life cycle management taking the necessary economic and ecological considerations into account. Thus, MSE has evolved over the last half century into a truly transdisciplinary field in its own right, crossing the boundaries of root disci- plines to describe, model and engineer new materials properties for target applications and new products. MSE is fundamental for several technologies. It addresses all stages of the innovation chain from fundamental research to advanced engineering applications, better production technologies and new products. The results of MSE research and development are found in all stages of the value chain from raw materials, via products and engi- neering systems, to technology validation; from new services to new solutions that meet the challenges that face today’s society. MSE continuously improves the competitiveness of both conventional industries and novel technology sectors. MSE innovation is the ‘raison d’être’ for many small-, medium- and large- scale industries.
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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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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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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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Advanced Density Functional Theory Methods tor Materials Science

Advanced Density Functional Theory Methods tor Materials Science

For me, this thesis has been more of a journey than a destination, and as with any voyage it is the people you travel with that makes it possible and worthwhile. I would first like to thank the entire Materials Science department for even admit- ting such a long-shot candidate as me in the first place and for being an amazing group of teachers. In particular, I have had valuable conversations with professors Brent Fultz, Harry Atwater, and Julia Greer who have been very generous with their time. Harry was especially helpful with his input on the photovoltaic work as was his students Jeff Bosco and Greg Kimball. I appreciate that Julia kindly let me play with some cutting-edge fabrication work down in the cleanroom. Finally, I am very grateful to my advisor Axel who brought me to Caltech and has been supportive of my work these past years and has had to put up with the temperamental artist in me.
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The components of abstracts: The logical structure of abstracts in the areas of materials science and technology and of library and information science

The components of abstracts: The logical structure of abstracts in the areas of materials science and technology and of library and information science

Rabinowitz and Vogel, cop. 2009). However, guidelines for the components of abstracts in the area of technical sciences were already researched in 1963 when Weil et al. (1963 b) stated that abstracts should be reader-oriented. In their opinion, abstracts in the area of technical sciences rarely need to mention WHO did the work, WHEN, or WHERE it was done or reported – unless these things were not clear in the bibliographic citation. Abstracts should state WHAT was found and, only when appropriate, WHY and HOW the work was done. An abstract in technical sciences should contain the purpose, findings, conclusions, recommendations, the chief experimental results (from which the conclusions were drawn), and indications of the methods used to obtain the data. It should not contain introductory or background materials, details of the experiment method, or detailed experiment results. Background materials should be included only if they are intended for readers who are not knowledgeable in the area. Details of the experimental methods should be included only if they are new. They should also be included if the full- length document is not readily available, or is in a language that readers are not likely to know.
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Fundamentals of Materials Science and Engineering 5th Edition pdf

Fundamentals of Materials Science and Engineering 5th Edition pdf

The earliest humans had access to only a very limited number of materials, those that occur naturally: stone, wood, clay, skins, and so on. With time they discovered techniques for producing materials that had properties superior to those of the natural ones; these new materials included pottery and various metals. Fur- thermore, it was discovered that the properties of a material could be altered by heat treatments and by the addition of other substances. At this point, materials utilization was totally a selection process, that is, deciding from a given, rather limited set of materials the one that was best suited for an application by virtue of its characteristics. It was not until relatively recent times that scientists came to understand the relationships between the structural elements of materials and their properties. This knowledge, acquired in the past 60 years or so, has empowered them to fashion, to a large degree, the characteristics of materials. Thus, tens of thousands of different materials have evolved with rather specialized characteristics that meet the needs of our modern and complex society; these include metals, plastics, glasses, and fibers.
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Planetary Materials Science and Astrobiology

Planetary Materials Science and Astrobiology

Planetary materials are composed largely of minerals. Other constituents include mineraloids (glasses and other amorphous solids), liquid phases (aqueous solutions, melts, pore fluids, organic compounds and others) and volatiles (atmospheres). None of the non- mineral components can be completely understood without consideration of the minerals with which they interact. Therefore, an understanding of planetary processes necessarily requires mineralogical investigation. Geochemistry and cosmochemistry are inextricably linked with mineralogy because minerals, and the aforementioned other constituents of planetary materials, are largely chemical systems. Therefore, an approach to planetary science grounded in mineralogy and chemistry can provide a wealth of insight into the processes and conditions that have shaped the solid material of the solar system. The guiding philosophy outlined above has been used as a grand-scale framework for the varied and diverse studies contained herein. Within this framework, mineral structures, assemblages, and compositions are integrated to elucidate planetary processes and environments. The general question addressed may be framed as follows: How can studies of primitive meteorites, impact crater secondary processes, and the bioalteration of subaqueous basaltic glass inform our understanding of the potential for life in the universe? This single question has been addressed in three distinct but related research streams.
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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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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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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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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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Requirements for the transfer of lead-free piezoceramics into application

Requirements for the transfer of lead-free piezoceramics into application

Hysteretic cyclic processes have the potential to lead to fatigue with increasing number of loading cycles [142]. Investigation of fatigue resistance can be conducted using bipolar, unipolar, or sesquipolar cycling. While the former is in general more severe and of interest for ferroelectric memories, unipolar loading results in slower property degradation and is relevant for actuators. However, please note that fatigue of ferroelectric memories is not considered here as we focus on piezoelectric applications. In the case of pie- zoceramic multilayer actuators, stability up to 10 9 electric cycles at temperatures up to 150 C may be required. It should also be noted that fatigue resistance was listed as the most important non- piezoelectric property in our survey of piezoceramic producers. Extensive summaries of the current state-of-the-art on electric fa- tigue of lead-free piezoceramics [143], which compare PZT to KNN- based, BCTZ-based, and NBT-based piezoceramics [130], can be found in the recent literature. Mechanistic considerations for fa- tigue of PZT included the effects of temperature and maximum electric fi eld and cumulated in a model based on charge carrier migration due to the depolarization fi eld [144]. Later studies found related effects in KNN-based [145] and BCTZ-based [146,147] ma- terials and were able to apply this model successfully. Moreover, fatigue in these two systems was found to be sensitive to vicinity of the phase transitions [147,148]. These determine the extent of the extrinsic domain contributions to the fi eld-induced strain, which are strongly in fl uenced by the agglomerated charge carriers. Acceptor doping was proposed as an approach to improve fatigue resistance in KNN-based materials [145], whereby the exact mechanism is still not clear. NBT-based ergodic relaxors reveal very low cyclic degradation, which was surmised to be due to the disappearance of the domain structure under decreasing electric fi eld and, therefore, the reduced depolarization fi eld [149]. Related materials also featured very low degradation, which was proposed to be related to the very low defect concentrations in the material [150].
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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

Science resources that were most available and sufficient in schools included. Text Books for science subjects: Biology, Chemistry and Physics for all classes. Also, most of the laboratory chemicals, science equipment and facilities were available in most schools. The science resources with least availability and low usage included the aquarium, animal cage, voltmeters, retort stands and science charts and diagrams.The ICT equipment which was rated as available in some schools included office computers, printers and photocopier. On the other hand, ICT hardware which was rated as not available and never used included LCD projector, satellite dish and decoder, overhead projector, television and video decoder/player (VHS). The average number of available laboratories per school and frequency of experiments was generally low. Most schools had only one room used for all three science laboratories. This makes it difficult for learners to differentiate one laboratory from the other. The frequency of experiments was also very low. Most experiments were conducted for Form IV class as the national examination approached. This deprives the learners the possibility of adequately comprehending the objectives and procedures of experiments as they are performed at a critical moment when the pressure for the examination is already very high. Consequently experiments are subjected to memorization diverting them from their original purpose of giving to students a hands-on application as per topic taught in science classes. The Government through the Ministries of Education Science and Technology (MoEST) and that of the President’s Office, Regional Administration and Local Governments (PORALG) should consider empowering the stakeholders on the relevance of compulsory science education.
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Advanced Composite Materials of the Future in Aerospace Engineering

Advanced Composite Materials of the Future in Aerospace Engineering

1) The Future of Composites in Aerospace Industry: Ceramic Matrix Composites (CMC): Efforts have been made to develop light weight, high temperature composite material at national aeronautics and space administration for use in Aircraft parts. Temperature rises as high as 1650 o c for turbine inlets of a conceptual engine and also for many parts in the engine. In order for materials to withstand such temperatures, the use of ceramic matrix composites (CMC) has been recommended. The uses of CMC’s in advanced engines withstand an increase in the temperature at which the engine can be operated, leading to increased yield.
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E-LEARNING MATERIALS FOR SOCIAL SCIENCE STUDENTS

E-LEARNING MATERIALS FOR SOCIAL SCIENCE STUDENTS

Today’s student population is rightfully categorized as digital natives. From the beginning of their educa- tion, they used ICT. The technological gadgets, internet, and social networks are like a glove to them. Such generation of students require more than just textbooks. In the 2013 University of Maribor establish a task force for e-learning materials development. The goal was to identify the optimal technological, didactical and financial approach to the long process of e-learning materials development. Members of the task force have many workshops presenting different views, acquired experiences from their previous projects, technological constraints, prediction, etc. During these workshops it was decided it would be the best to prepare different types of e-learning materials and test them by the students. From their feedbacks we could set the guidelines for large scale production. At the Faculty of Arts, Faculty of Natural Sciences and Mathematics and Faculty of Education students needs to acquire also the digital competences to become successful teachers. For special didactics study programs different types of e-learning materials were produced with different technological approach. The concept was to upgrade the previous deliver- ables (PowerPoint slides) and narrate them. Narrated slides would enable students to refresh their lec- tures and should be used as blended e-learning materials. Narrations were prepared in different format: textual narration, voice narration and video narration. But later it was decided that these types are not enough and a mix of narratives (integrated multimedia learning materials) could be used on individual slides depending on the content of the slide.
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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

(99.995+% purity, 45Im, Aldrich) was slowly added to a mixture of fuming nitric acid (25mℓ) and sulfuric acid (50mℓ). The mixture was kept for 30 minutes. The mixture was cooled down to 5°C in an ice bath. Also 25.0g of potassium chlorate was slowly added to the solution while stirring for 30 minutes. Since a lot of heat was produced while adding potassium chlorate into the mixture, special care during this step is needed to smear out temperature effect. The solution was heated up to 70°C for 24 hours and was then placed in air for 3 days. Most of graphite was precipitated on the bottom but some reacted carbons were floating. The floating carbon materials were transferred into DI water (1ℓ). After stirring it for 1 hour, the solution was immediately filtrated and the sample was dried. The formed CNT was doped by TiO 2 using thermal annealing at temperatures 450,500,550 and 600
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