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This paper aims to investigate the effect and mechanism of O atom single doping, Ce and O atoms co-doping on the interfacial microscopic behavior of brazed Ni-Cr/diamond.

Using first-principles calculations, the embedding energy, work of separation, interfacial energy and electronic structures of Ni-Cr-O/diamond and Ni-Cr-O-Ce/diamond interface models were calculated. Then, the effect of Ce and O co-doping was experimentally verified through brazed diamond with CeO₂-added Ni-Cr filler alloy.

The results show that O single-doping reduces the interfacial bonding strength between Ni-Cr filler alloy and diamond but enhances its interfacial stability to some extent. However, the Ce and O co-doping simultaneously enhances the interfacial bonding strength and stability between Ni-Cr filler alloy and diamond. The in-situ formed Ce-O oxide at interface impedes the direct contact between diamond and Ni-Cr filler alloy, which weakens the catalytic effect of Ni element on diamond graphitization. It is experimentally found that the fine rod-shaped Cr₃C₂ and Cr₇C₃ carbides are generated on diamond surface brazed with CeO₂-added Ni-Cr filler alloy. After grinding, the brazed diamond grits, brazed with CeO₂-added Ni-Cr filler alloy, present few fracture and the percentage of intact diamond reaches 67.8%. Compared to pure Ni-Cr filler alloy, the brazed diamond with CeO₂-added Ni-Cr filler alloy exhibit the better wear resistance and the slighter thermal damage.

Using first-principles calculations, the effect of Ce and O atoms co-doping on the brazed diamond with Ni-Cr filler alloy is investigated, and the calculation results are verified experimentally. Through the first-principles calculations, the interface behavior and reaction mechanism between diamond and filler alloy can be well disclosed, and the composition of filler alloy can be optimized, which will be beneficial for synergistically realizing the enhanced interface bonding and reduced thermal damage of brazed diamond.

The purpose of this paper is to explore the scientific nature of work-based learning (WBL) and research as operationalized in Professional Studies by examining first principles of scientific inquiry.

This paper introduces a Professional Studies program as it has been implemented at University of Southern Queensland in Australia and examines it from the perspective of five first principles of scientific inquiry: systematic exploration and reporting, use of models, objectivity, testability and applicability. The authors do so not to privilege the meritorious qualities of science or to legitimise WBL or its example in Professional Studies by conferring on them the status of science, but to highlight their systematised approach to learning and research.

If the authors define Professional Studies to mean the systematic inquiry of work-based people, processes and phenomena, evidence affirmatively suggests that it is scientific “in nature”.

WBL has been well documented, but its orientation to research, particularly mixed methods (MM) research through Professional Studies, and its adherence to first principles of science have never been explored; this paper begins to uncover the value of work-based pedagogical approaches to learning and research.

This paper aims to study the mechanism of hydrogen embrittlement in 12Cr2Mo1R(H) steel, which will help to provide valuable information for the subsequent hydrogen embrittlement research of this kind of steel, so as to optimize the processing technology and take more appropriate measures to prevent hydrogen damage.

The hydrogen diffusion coefficient of 12Cr2Mo1R(H) steel was measured by the hydrogen permeation technique of double electrolytic cells. Moreover, the influence of hydrogen traps in the material and experimental temperature on hydrogen diffusion behavior was discussed. The first-principles calculations based on density functional theory were used to study the occupancy of H atoms in the bcc-Fe cell, the diffusion path and the interaction with vacancy defects.

The results revealed that the logarithm of the hydrogen diffusion coefficient of the material has a linear relationship with the reciprocal of temperature and the activation energy of hydrogen atom diffusion in 12Cr2Mo1R(H) steel is 23.47 kJ/mol. H atoms stably exist in the nearly octahedral interstices in the crystal cell with vacancies. In addition, the solution of Cr/Mo alloy atom does not change the lowest energy path of H atom, but increases the diffusion activation energy of hydrogen atom, thus hindering the diffusion of hydrogen atom. Cr/Mo and vacancy have a synergistic effect on inhibiting the diffusion of H atoms in α-Fe.

This article combines experiments with first-principles calculations to explore the diffusion behavior of hydrogen in 12Cr2Mo1R(H) steel from the macroscopic and microscopic perspectives, which will help to establish a calculation model with complex defects in the future.

Guidelines for the design of knowledge-based e-learning usability systems are absent from the current recognized set of usability design heuristics and from an established evaluation methodology of e-learning system developments. Such systems can help Web designers and instructional designers design for different user needs and decide which properties are of a higher priority, thus meriting more design and development efforts. The authors aim to help students develop higher-order thinking skills, such as application, evaluation and syntheses of knowledge.

The authors applied Merrill ' s first principles of instruction and usability properties as pedagogical and usability design guidelines, knowledge management (KM) and hierarchical task analysis as methodological knowledge bases. The authors proposed a KM e-learning usability framework which frames our mapping of Web usability attributes to e-learning usability properties. The authors aim to investigate whether adopting Merrill ' s first principles of instruction and usability properties as knowledge-based guidelines/design factors would help learners develop higher-order thinking skills and whether this design would result in positive technology acceptance. The authors also developed a method matrix to map the selected methods of cognitive engineering to its potential uses in the KM e-learning usability framework of this paper and mapped e-learning usability tools with components in the KM e-learning usability system.

Findings indicated that our design effectively helped learners to demonstrate higher-order thinking skills and positive technology acceptance, promising indications toward the design and development of knowledge-based usability frameworks and systems.

The sample size of this paper is small. Hence, conclusions are not generalizable at this moment.

The authors’ contributions are twofold: First, the authors proposed a KM e-learning usability framework, which frames the mapping of KM processes to e-learning principles and usability properties. Second, the authors proposed a method matrix which maps the selected methods of cognitive engineering to its potential uses in their KM e-learning usability framework. Based on these mappings and focusing on the usability properties navigation and learning support, the authors used ICT/Web2.0 tools to present/visualize information more clearly and more sensibly/manageably to students, to help trigger new knowledge and develop higher-order thinking skills, such as application, evaluation and syntheses of knowledge and articulate information from different perspectives throughout the KM life cycle.

With excellent mechanic properties and hydrogen embrittlement (HE) resistance, 12Cr2Mo1R(H) steel is suitable to make hot-wall hydrogenation reactors. However, longtime exposure to a harsh environment of high-pressure hydrogen at medium temperature in practical application would still induce severe hydrogen uptake and eventually damage the mechanical properties of the steel. The study aims to evaluate the HE resistance of the steel under different tensile strain rates after hydrogen charging and analyze the hydrogen effect from atomic level.

This research studied the HE properties of 12Cr2Mo1R(H) steel by slow strain rate tests. Meanwhile, the effect of hydrogen on the structures and the mechanical properties of the simplified models of the steel was also investigated by first-principle calculations.

Experimental results showed that after hydrogen pre-charging in this work, hydrogen had little effect on the microstructure of the steel. The elongations and reduction of cross-sectional area of the samples reduced a lot, by contrast, the yield and tensile strengths changed slightly. The 12Cr2Mo1R(H) steel was not very susceptible to HE with a maximum embrittlement index of about 20.00%. First principles calculation results showed that after H dissolution, lattice distortion occurred and interstitial H atoms would preferentially occupy the tetrahedral interstitial site in bcc-Fe crystal and increase the stability of the supercells. With the increase of H atoms added into the simplified model, the steel still possessed a good ductility and toughness at a low hydrogen concentration, while the material would become brittle as the concentration of hydrogen continued to increase.

These finds can provide valuable information for subsequent HE studies on this steel.

Today's technology supports the design of more and more sophisticated interactive learning environments. This paper aims to argue that such design should develop from first principles.

In the paper by first principles is meant: learning theory and principles of course design. These principles are briefly outlined, key features of which include: the use of knowledge and task analysis methodology; the use of topic maps; and learning design that supports adaptive teaching. The paper goes on to describe how this approach to course design has been applied at the UK Defence Academy.

The paper shows how conversation theory serves as a source of first principles for the design of interactive learning environments, as exemplified in the Course Assembly System and Tutorial Environment (CASTE).

A principled approach to the design of interactive learning environments is of value in bringing order to a conceptually and methodologically confused domain of practice.

With the increasing mobility of higher education students across the world, institutions and instructors are confronted with the need to mitigate the linguistic challenges that multilingual students face in learning advanced content in universities or colleges where English or another language is the medium of instruction. This usually pertains to students who have low competence in the language of instruction, as it is a second or third foreign language for them, hence encountering difficulties in the mastery of discipline-specific content and knowledge. First and foremost, this chapter explores the specific linguistic barriers that multilingual students encounter in this context, which relate to several elements of communicative competence in the language of instruction, while investigating empirical studies on instructional strategies for multilingual classes. Secondly, it discusses the use of Merrill’s (2013) first principles of instruction as the main framework in the design of technology-enhanced lesson plans and in the selection implementation of technology-nested instructional strategies, which can assist instructors in creating linguistically inclusive learning environments across disciplines, while maintaining high academic standards. The chapter critically addresses the use of ICT tools in supporting instructional strategies and lesson plan design to mitigate students’ linguistic difficulties with the receptive and productive language skills within discipline-specific contexts. Finally, it provides a lesson plan template and examples encouraging instructors to carefully plan and design instruction and to experiment and monitor the outcomes in their classes.

This chapter outlines potential steps to take in designing active learning experiences based on several theories underlying the learning process. The chapter examines theories of learning and instruction including information processing, schema acquisition, and cognitive load theory. Next follows an explanation of how these theories support problem-centered learning as well as a rationale for the need to help learners develop domain-general, flexible problem-solving skills that will transfer to future needs and contexts. The second half of the chapter focuses on designing active learning experiences based on the selection of real-world problems as the foundation for learning, activating prior knowledge, demonstration of the process or concept, multiple opportunities for practice with relevant scaffolding, and the chance to integrate that knowledge into the learners’ own context based on M. D. Merrill’s (2002) First Principles of Instruction. Examples of assessments, strategies, and activities to foster active, problem-centered learning drawn from the literature are also provided.

This chapter presents a comparative analysis of the English, Northern Irish, Arab Israeli, Trinidad and Tobago and the US cases. The focus is what we have learned from the research about: the relationships within Education Governance Systems to navigate turbulence; building capacity for empowering senior-level leaders to deliver on their manifestos and outstanding track records for school improvement; reducing the achievement gap between dominant groups and marginalised groups in International Governance Systems. The chapter identifies that all cases require participatory multi-stakeholder action to develop and support collaborative networked learning communities in practice. Such communities of and for practice need to Empower Young Societal Innovators for Equity and Renewal (EYSIER). Policy and Education Governance Systems have the potential to synthesise the best of what has been said and done in the past, with innovative ways of working by empowering networks of knowledge building and advocacy. These networks co-create opportunities for action learners to work together to describe intersectionalities of discrimination and begin to remove fear of discrimination and marginalisation from Education Governance Systems. From this position, senior-level leaders can work with their leaders, teachers, parents and students to optimise how learning about the self, and learning how to learn improves community education for all students and EYSIER.

This article seeks to reflect on the role of key concepts in foresight and futures work. The goal is to explore a set of concepts and link them to the effects they have in the world of foresight practice. It is argued that concepts order foresight practice and that though each foresight context and practitioner is unique, concepts bring a sense of order and coherence to foresight work and futures thinking. This reflection is placed in the context of a set of first principles the author acknowledges as his starting place for futures thinking and foresight practice.

The paper takes the form of conceptual analysis.

Concepts have effects and these can be assessed based on their ability to increase social and personal resilience in contexts characterised by change, complexity and uncertainty.

Foresight practitioners clarify their own values and ethics through reflection on the concepts they use and the processes they deploy when working with clients.

More reflective foresight practice; greater conceptual clarity when reflecting on and communicating/teaching foresight and futures thinking.

This paper offers a basis for orienting foresight work towards the broader social goal of resilience through a deepened appreciation of how concepts inform process and structure meaning.