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The purpose of this paper was to prepare the cerium-based conversion coating on AZ91D magnesium alloy, and its compositions, micro-morphology, corrosion resistance and the chemical valence state of the film elements were investigated.

The methodology comprised preparation of coatings at different temperatures, which then were characterized using scanning electron microscopy coupled with energy dispersive X-ray spectroscopy, an electrochemistry workstation and by means of X-ray photoelectron spectroscopy.

The conversion coating had a micro-cracked morphology. The conversion coatings were composed of MgO (or Mg-OH), CeO₂ and Ce2O₃. The best corrosion resistance of the cerium passivation film appeared when the treatment temperature was about 35°C.

The corrosion current densities of conversion coatings were lower by one to two orders of magnitude than the corrosion current density of the blank sample. The rare earth passivation coating prepared under the best condition could reduce the corrosion current to 3.548 × 10−6 A/cm2.

The theoretical findings serve as a foundation for further research into understanding sulfide-based solid-state electrolytes, ultimately advancing the progress of all-solid-state batteries.

The electronic properties of Li₇P₃S₁₁ are thoroughly explored through first-principles calculations.

This investigation encompasses the intricate atom-dominated valence and conduction bands, spatial charge density distribution and the breakdown of atom and orbital contributions to van Hove singularities. Additionally, the compound’s wide and discrete energy spectra reflect the substantial variations in bond lengths and its highly anisotropic geometric structure. The complex and nonuniform chemical environment indicates the presence of intricate hopping integrals.

This study provides valuable insights into the critical multiorbital hybridizations occurring in the Li-S and P-S chemical bonds. To validate the theoretical predictions, experimental techniques can be employed. By combining theoretical predictions with experimental data, a comprehensive understanding of the geometric and electronic characteristics of Li₇P₃S₁₁ can be achieved.

The purpose of this paper is to introduce and analyze a new blast-wave impact-mitigation concept using advanced computational methods and tools. The concept involves the use of a protective structure consisting of bimolecular reactants displaying a number of critical characteristics, including: a high level of thermodynamic stability under ambient conditions (to ensure a long shelf-life of the protective structure); the capability to undergo fast/large-yield chemical reactions under blast-impact induced shock-loading conditions; large negative activation and reaction volumes to provide effective attenuation of the pressure-dominated shockwave stress field through the volumetric-energy storing effects; and a large activation energy for efficient energy dissipation. The case of a particular bimolecular chemical reaction involving polyvinyl pyridine and cyclohexyl chloride as reactants and polyvinyl pyridinium ionic salt as the reaction product is analyzed.

Direct simulations of single planar shockwave propagations through the reactive mixture are carried out, and the structure of the shock front examined, as a function of the occurrence of the chemical reaction. To properly capture the shockwave-induced initiation of the chemical reactions during an impact event, all the calculations carried out in the present work involved the use of all-atom molecular-level equilibrium and non-equilibrium reactive molecular-dynamics simulations. In other words, atomic bonding is not pre-assigned, but is rather determined dynamically and adaptively using the concepts of the bond order and atomic valence.

The results obtained clearly reveal that when the chemical reactions are allowed to take place at the shock front and in the shockwave, the resulting shock front undergoes a considerable level of dispersion. Consequently, the (conserved) linear momentum is transferred (during the interaction of the protective-structure borne shockwaves with the protected structure) to the protected structure over a longer time period, while the peak loading experienced by the protected structure is substantially reduced.

To the authors’ knowledge, the present work is the first attempt to simulate shock-induced chemical reactions at the molecular level, for purposes of blast-mitigation.

This study aims to present a high-end lesson study (HELS) model to develop students' subject competency. Data were collected from a Beijing suburban key senior high school in China. How the subject competency framework (SCF) supports HELS and develops students' subject competency in practice are discussed in this study.

This study provides a four-dimensional SCF developed by the chemistry education research team at Beijing Normal University. Basic procedures of the HELS model involve the project plan, students' pre-test, lesson design workshop, first-round teaching implementation and improvement, second-round teaching implementation and evaluation, students' post-test, and results discussion. Data were collected from each of the procedures, and analysis of the data is conducted in both qualitative and quantitative approaches.

The results show that the SCF supports HELS implementation by (1) identifying key teaching objectives based on curriculum standard requirements and students' subject competency performance; (2) organizing teaching content based on the core knowledge to develop cognitive mode; (3) designing tasks and activities regarding understanding–applying–transferring and innovating categories and sub-categories of SCF; (4) establishing students' cognitive perspectives and reasoning paths to promote their subject competency by teacher–student interaction.

The HELS model provides theory-based pedagogical guidance for conducting lesson studies. It presents the SCF and orientation. The SCF is used throughout the entire process of HELS, including the identification of teaching objectives, the selection and organization of teaching content, and the design and implementation of teaching activities. It reflects a systematic instructional design–implementation–discussion–improvement–evaluation process. The SCF-based HELS can be applied to different topics and disciplines.

Given the limited empirical work investigating personal characteristics of industrial sales people as related to their reward valences and the limitation of measuring valences at a single level, previous research is extended by examining the relationships between industrial sales people′s personal characteristics and their valences for multiple levels of various rewards. A conceptual framework is presented, previous studies reviewed, hypotheses offered, the methodology explained, and the results and implications of the study discussed.

Recent years have witnessed a rise in interest in neuromarketing from academia and industry, as it offers practical tools for determining consumers' subconscious reactions to marketing stimuli. Despite this, the current state of neuromarketing research is not well supported by empirical data. To offer a thorough overview of the studies conducted on this discipline in the past few years, a bibliometric analysis of neuromarketing is carried out, taking into account its techniques, key areas and publication patterns trends from several viewpoints.

This study searched 463 documents for the web of science databases published during the previous sixteen years and visualized them. The graphical display of data was created using the VOS Viewer software.

Electroencephalogram (EEG) appeared as a predominantly tool used in neuromarketing research. EEG is either used alone or together with Human Eye-Tracking (HET). “Emotions” was identified in the study as a crucial area of neuromarketing, among other pertinent concepts. The study's results also showed that authors from the United States produced the most articles on neuromarketing, followed by those from the United Kingdom and Spain. The publishing trend, sources and major contributors in neuromarketing are identified using Web of Science data from 2006 to 2021. Overall, the research provides insight into neuromarketing's past, present and future as well as the most widely utilized analytical techniques.

The study's conclusions will be of interest to researchers in understanding the journals that publish neuromarketing research, the themes that contributors and writers have identified, and the countries where research is carried out. This is the first comprehensive study, to the authors' knowledge, that provides a general summary of the key trends in neuromarketing research throughout its history. To the authors' knowledge, this is the first thorough study that offers a broad overview of the most important developments in neuromarketing research from 2006 to 2021.

The aim of this paper is to examine how indoor aromatization affects the expressed and unexpressed satisfaction with the work environment in the production hall of an industrial company.

The aroma was flavored by an aromatization unit, the expressed satisfaction was measured on a scale and biometrics of facial recognition (FaceReader) was used to measure unexpressed satisfaction, enabling the recording of eight emotions and two basic emotions.

Research has shown the effect of aroma on two emotions – neutral and angry – which partially confirmed the sense of flavoring production facilities. Previous research has shown that positive feelings caused by a pleasant smell influence customers' purchasing decisions. As the use of aroma affects the mental state of the individual, it could be also applied for non-marketing purposes.

To date, there has been no research that systematically addresses the impact of aromatization on the perception of the work environment in a manufacturing company. The presented study is unique in its design and focus and provides basic information about the impact of aroma on individuals. The findings of this study can help to examine further aspects that indirectly affect performance.

APPLICATION of the so‐called high energy liquid fuels and high energy liquid oxidizers to power plants based on the jet propulsion principle is receiving the increasing interest and attention of rocket propellant chemists and power plant engineers universally. The aspect of substantially increased—as much as 50 per cent— energy per pound of propellant load or per cubic foot of propellant tankage over today's propellants has whetted scientific appetites and justified probing the field of high energy chemicals to determine, as logically and as practically as we can at the present time, the gains, problems, limitations and applications of these higher energy chemicals. The object of this paper is, in a general way, to discuss the subject of chemical rocket propellants in such a way that the following five questions will be, in part at least, answered or recalled to the minds of this audience for additional deliberation.

The purpose of this paper is to analyze various properties of anatase titanium dioxide (TiO₂) nanoparticles. Further, it proposes to implement Linear Combinations of Atomic Orbitals (LCAO) basis set under the framework of density functional theory and outline how LCAO is able to provide improved results in terms of various mechanical properties rather than plane wave and other theoretical results.

This paper provides an exploratory study on anatase TiO₂ by implementing OLCAO–DFT–LDA–LBFGS–EOS–PZ algorithms to find out various ground-level properties. The data so obtained are complemented by various analysis using mathematical expressions, description of internal processes occurred and comparison to others’ analytical results.

The paper provides some empirical insights on how mechanical properties of anatase TiO₂ improved by implementing LCAO methodology. From the analysis of electronic properties, it is seen that the anatase TiO₂ supports the inter band indirect transition from O-2p in valence region to Ti-3d in the conduction region.

Most of the electronic properties are underestimated because a single exchange-correlation potential is not continuous across the gap. This gap can be enhanced by implementing Green’s function in place of DFT and the other way is to implement self-interaction correction.

The use of anatase TiO₂ is primarily used for catalytic applications. This is also used to enhance the quality of paper in the paper industry. Additionally, this is used as a prime ingredient in cosmetic industry.

This paper fulfills an identified need to study how LCAO, another basis set, plays an important role in improving material properties.

This study aims to investigate the effect of V doping on the microstructure, chemical stability, mechanical and vacuum tribological behavior of sputtered MoS₂ coatings.

The MoS₂-V coatings are fabricated via tuning V target current by magnetron sputtering technique. The structural characteristic and elemental content of the coatings are measured by field emission scanning electron microscopy, X-ray diffractometer, electron probe X-ray micro-analyzer, Raman, X-ray photoelectron spectroscopy, high resolution transmission electron microscope and energy dispersive spectrometer. The hardness of the deposited coatings are tested by a nanoindentation technique. The vacuum tribological properties of MoS₂-V coatings are studied by a ball-on-disc tribometer.

Introducing V into the MoS₂ coatings results in a more compact microstructure. The hardness of the coatings increases with the doping of V. The MoS₂-V coating deposited at a current of 0.2 A obtains the lowest friction coefficient (0.043) under vacuum. As the amount of V doping increases, the wear rate of the coating decreases first and then increases, among which the coating deposited at a current of 0.5 A has the lowest wear rate of 2.2 × 10–6 mm³/N·m.

This work elucidates the role of V doping on the lubrication mechanism of MoS₂ coatings in a vacuum environment, and the MoS₂-V coating is expected to be applied as a solid lubricant in space environment.