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The authors are developing a model for rural science teacher professional development, building teacher expertise and collaboration and creating high-quality science lessons: technology-mediated lesson study (TMLS).

TMLS provided the means for geographically distributed teachers to collaborate, develop, implement and improve lessons. TMLS uses technology to capture lesson implementation and collaborate on lesson iterations.

This paper describes the seven steps of the TMLS process with examples, showing how teachers develop their content and pedagogical knowledge while building relationships.

The TMLS approach provides an innovative option for teachers to collaborate across distances and form strong, lasting relationships with others.

Referring to transaction costs theory, resource based view and social exchange theory, this paper examines the interplay between selected dimensions of suppliers’ relationships with foreign buyers, specifically relational trust, contract specificity and relationship-specific investments, as well as analyzes the effects those dimensions have on the suppliers’ product innovation.

This study uses survey data from 179 small- and medium-sized Polish manufacturing suppliers of high-tech products. Information was collected on dyadic relationships with their key foreign buyers and used as an input to a structural model consisting of multiple linear regressions.

It was discovered that trust and investments have a mutual positive impact on each other and individually contribute to the supplier’s product innovation. However, once both trust and investments were included in the model, only the latter showed significant effect. Contracts, on the other hand, showed different impact on innovation depending on how it was measured.

Managers should treat trust only as a mechanism to create supportive environment for investments, which exclusively have the power to improve supplier’s product innovation. Contracts’ role, in turn, should be limited to facilitating business relationships.

Only single quantitative studies analyzed trust, investments and contracts as determinants of supplier’s product innovation. Also, focus was not placed on high-tech SMEs in relationships with foreign buyers. As a result, our study provides unique insights on such relationships and unveils new details on an indirect link between trust and product innovation.

The purpose of this study is to prepare a new adsorbent activated carbon immobilized on polystyrene (ACPS) for uranium (VI) and thorium (IV) removal from an aqueous solution. Activated carbon (AC) was derived from biochar material by chemical activation to increase the active sites on its surface and enhance the adsorption capacity. Activated carbon (AC) was immobilized on polystyrene (PS) to improve the physical properties and facilitate separation from the working solution. A feasibility study for the adsorption of uranium (VI) and thorium (IV) on the new adsorbent (ACPS) has been achieved. Adsorption kinetics, isotherms, and thermodynamics models of the adsorption process were used to describe the reaction mechanism.

Activated carbon was synthesized from biochar charcoal by 2 M H₂SO₄. Activated carbon was immobilized on the pretreatment polystyrene by hydrothermal process forming new adsorbent (ACPS). Characterization studies were carried out by scanning electron microscope, energy-dispersive X-ray spectrometer, infrared spectroscopy and X-ray diffraction techniques. Different factors affect the adsorption process as pH, contact time, solid/liquid ratio, initial concentration and temperature. The adsorption mechanism was explained according to kinetic, isothermal and thermodynamic studies. Also, the regeneration of spent ACPS was studied.

The experimental results showed that pH and equilibrium time of the best adsorption were 6.0 and 60 min for U(VI), 4.0 and 90 min for Th(IV), (pH_PZC = 3.4). The experimental results fit well with pseudo-second order, Freundlich and Dubinin–Radushkevich models proving the chemisorption and heterogenous adsorption reaction. Adsorption thermodynamics demonstrated that the adsorption process is exothermic and has random nature of the solid/liquid interface. In addition, the regeneration of spent ACPS research showed that the adsorbent has good chemical stability. According to the comparative study, ACPS shows higher adsorption capacities of U(VI) and Th(IV) than other previous bio-adsorbents.

This study was conducted to improve the chemical and physical properties of bio-charcoal purchased from the local market to activated carbon by hydrothermal method. Activated carbon was immobilized on polystyrene forming new adsorbent ACPS for eliminating U(VI) and Th(IV) from aqueous solutions.

This paper aims to demonstrate that, in line with the emerging trend of multifunctional yarn development, cotton yarn can effectively harness renewable solar energy to achieve photothermal conversion and thermochromism. This innovation not only maintains the comfort associated with natural fiber cotton yarn but also enhances its ultraviolet (UV) light resistance.

In this work, 4% zirconium carbide (ZrC) and thermochromic powder were adhered to cotton yarn through polyurethane (PU) by sizing coating method. After sizing, the two cotton yarns are twisted by ring spinning to obtain composite yarns with photothermal conversion and thermochromic functions.

The yarn obtained by cotton/6%PU/8% thermochromic dye single yarn and cotton/6%PU/4% ZrC single yarn composite is the best match. After 5 min of infrared light, the temperature of the composite yarn rose to the maximum, increasing by 36.1°C. The ΔE* value before and after irradiation of infrared lamp is 26.565, which proves that the thermochromic function is good. The yarn dryness unevenness was significantly reduced by 27.2%. The composite yarn has a UPF value of up to 89.22, and its performance characteristics remain stable after 100 minutes of washing.

The composite yarn’s photothermal conversion and thermochromism functions are mutually reinforcing. Using sunlight can simultaneously achieve heating and discoloration effects without consuming additional energy. The cotton yarn used in this application is versatile, and suitable for a wide range of uses including clothing, temperature visualization detection and other scenarios.

The study assesses the most significant architectural core technological system that converges into a Battery Electric Vehicle (BEV).

Conceptually grounded in the convergence phenomenon and utilizing the graph theory-based network construction approach, based on the Betweenness Centrality (BC) metric, core International Patent Classifications (IPCs) have been empirically identified. Based on these IPCs, the ownership structure of the patents was established through assignee analysis.

Analyzing the networks obtained at different IPC levels, we found that multiple technologies have converged in a BEV, from battery chemistry to electrical engineering and thermal management of electrical machines.

The outcome of this work has led to the identification of BEV technologies, which can be further developed to assess the trends of technologies and associated gaps and aid technology management for the selection, acquisition, and exploitation of technology.

The outcome of this work will aid technology management practitioners in better planning the selection, acquisition, and exploitation of technologies associated with BEV.

The paper adds an evidence-based approach to the body of knowledge to identify the built-in technologies that produce a BEV.

Metaverse means a world in which virtual and reality interact and co-evolve, and social, economic, and cultural activities are carried out in it immersively. In this scenario, it goes beyond just combining the physical and virtual worlds – there is a continuity between them, creating an ecosystem that merges the two universes (physical and virtual). This scenario is considered an innovative educational environment that enhances technologies related to the metaverse, which results in the fusion of resources and elements from the real with the virtual. Thus, the goal of this chapter is to map what an innovative digital learning environment with the metaverse looks like. In order to address these issues, a comprehensive and integrative review was conducted in the Scopus and Web of Science (WoS) databases. (1) What is the metaverse? and (2) How can metaverse be used to create a cutting-edge digital learning environment? Results show that the metaverse may be integrated with problem-based learning, gamification, and maker culture approaches to create an even more creative and successful learning environment. This chapter will give an illustration of how a creative digital learning environment may be created utilizing the metaverse.

This study aims to synthesize two different benzoxazines (Bz) monomers using bio-based and petroleum-based primary amines, respectively, and they have been compared to study their thermal and mechanical performances.

A bio-based bisphenol, Divanillin (DiVa), was formed by reacting two moles of vanillin with one mole of ethylenediamine (EDA) which was then reacted firstly with paraformaldehyde and EDA to form the benzoxazine DiVa-EDA-Bz, and secondly with paraformaldehyde and furfuryl amine (FFA) to form the benzoxazine DiVa-FFA-Bz. The molecular structure and thermal properties of the benzoxazines were characterized by fourier transform infrared spectroscopy and nuclear magnetic resonance (1H,13C) spectroscopies, differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), respectively. The benzoxazines were further coated on mild steel panels to evaluate their mechanical properties and chemical resistance.

The DSC results of DiVa-FFA-Bz showed two exothermic peaks related to crosslinking compared to the one in DiVa-EDA-Bz. The DiVa-FFA-Bz also showed a higher heat of polymerization than DiVa-EDA-Bz. The TGA results showed that DiVa-FFA-Bz exhibited higher thermal stability with a residual char of 54.10% than 43.24% for DiVa-EDA-Bz. The chemical resistance test results showed that DiVa-FFA-Bz showed better chemical resistance and mechanical properties due to its higher crosslinking density.

This study shows the use of bio-based materials, vanillin and FFA, for synthesizing a benzoxazine resin and its application at high temperatures.

This study aims to prepare thymol-based deep eutectic solvents (DESs) and use them as lubricates for friction and wear tests to simulate the wear conditions of hybrid bearings.

Through the characterization and analysis of the morphology of wear scars and the elemental composition of friction films, the tribological behavior and wear mechanism of sample materials as lubricants were investigated and the anti-wear mechanism of thymol-based DESs was discussed.

The findings demonstrate that because of the formation of a fluid lubrication film and excellent kinematic viscosity, the lubrication effect of the prepared DES is improved by about 50% compared to the base lubricating oil. The prepared [Ch]Cl-thymol DES has a better anti-friction and lubrication effect than citric-thymol, EG-thymol and urea-thymol DESs, with an average friction coefficient of about 0.04.

In this work, the friction reduction properties of thymol-based DESs were studied as lubricants for the first time, and the lubrication mechanism of sample materials was investigated.

The lubricating fluid stored in the porous matrix will spontaneously exude to supplement the lubricating film in the damaged area, thus ensuring the long-term self-lubricating function of the porous surface. To reveal the repair mechanism of oil film, it is necessary to understand the flow characteristics of oil in micropores. The purpose of this study guides the design of micropore structure to realize the rapid exudation of oil to the porous surface and the rapid repair of the lubricating film.

In this paper, cylindrical orifice, convergent orifice and divergent orifice were studied. The numerical model of lubricating oil exudation in micropores was established. The distribution characteristics of oil pressure, velocity and three-phase contact line in the process of oil exudation were investigated. The effects of different orifice shapes and orifice structure parameters on the pinning and spreading characteristics of oil droplet were analyzed. Then the internal mechanisms of oil droplet formation and spread on the orifice surface were summarized.

The results show that during the process of oil exudation, the three-phase contact line of the oil drop is pinned once at the edge of the cylindrical and convergent orifice. Compared with the three orifice structures, the inlet pressure of the oil drop is low, and the oil velocity at the pinning point is stable in the divergent orifice. Resulting in favorable oil exudation. It is easier for oil droplet to depin by appropriately reducing the wall wetting angle, increasing the aperture or controlling the wall inclination angle. Ensure the self-healing and long-lasting lubrication film of porous oil-bearing surfaces.

The effect of pore structure on the flow behavior of lubricating fluid has always been concerned. But the mechanism by which different orifice shape affect the pinning behavior of oil droplets is not yet clear, which is crucial for understanding the self-healing mechanism of oil films on porous surfaces. It is meaningful to analyze the mechanism of oil exudation and spreading on the porous surface of oil in the special orifice, to optimize the design of the orifice structure.

Orifice shape has influence on internal flow field parameters. There is no report on the influence of orifice shape on the film formation process of oil seepage and diffusion from pores. The effects of different orifice shapes and orifice structure parameters on the characteristics of oil droplet pinning and diffusion were studied.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-04-2024-0118/