This study aims to investigate the influence of result-centric narrative structures in textbooks on teachers' explanatory mechanisms and to analyze the effects of providing mechanism-centered explanatory tools on shifting teachers' perceptions. The research procedure followed a four-stage design, which involved analyzing the narrative structures of textbooks for "Matter and Energy"-a high school elective under the 2022 Revised National Curriculum-and diagnosing the initial explanatory mechanisms of ten in-service chemistry teachers. Subsequently, after providing educational materials on catalytic mechanisms, the changes in teachers' perceptions were analyzed. The results revealed that all four textbooks focused predominantly on result-centric descriptions, such as the reduction of activation energy, and visual representations centered on energy diagrams. This structure was found to be a cause for confining teachers' thinking to a phenomenological level. However, teachers who subsequently encountered qualitative mechanism-based explanatory tools re-envisioned them as essential cognitive scaffolding rather than an instructional burden, demonstrating a distinct epistemological shift from simple 'conclusion transmitters' to 'causal explainers' who reveal the underlying causes of phenomena. This study suggests that for teachers to grow as agents of scientific explanation, it is necessary to strengthen their capacity for causal explanation within teacher education programs. Furthermore, it proposes that institutional legitimacy for providing causal explanations should be granted to teachers by officially specifying the inclusion of mechanistic explanations of catalysis within the national curriculum and textbooks.
This study aims to explore how high school students understand dynamic equilibrium from a kinetic perspective in phase equilibrium contexts. To this end, a survey was administered to 92 students enrolled in Chemistry II at a general high school in Chungcheongnam-do, South Korea. The survey asked students to describe changes in evaporation and condensation rates, as well as the time required to reach equilibrium and the rates at equilibrium under conditions of temperature change. Students' responses were analyzed by categorizing response types and identifying patterns of reasoning. The results showed that students experienced greater difficulty in understanding evaporation rates and rates at equilibrium than condensation rates. In particular, the concept of evaporation rate was found to function as a threshold concept that drives integrative understanding of related kinetic concepts in students' kinetic understanding of dynamic equilibrium. In addition, many students showed a tendency to struggle with integratively considering the time to reach equilibrium and the rates at equilibrium when temperature changed. These findings suggest the need to explicitly address the concept of evaporation rate in teaching dynamic equilibrium and to emphasize an integrative kinetic approach to equilibrium shifts under temperature change, rather than treating each aspect as an isolated category.
This study analyzed teachers' noticing of high school student's problem-solving through the think-aloud method. Ten teachers with diverse backgrounds participated. Student problem-solving videos and worksheets were used during semi-structured interviews. The findings revealed that many teachers attended to the overall aspects of the understanding stage in students' problem-solving process. The teachers focused on student's recall of related concepts or laws where errors occurred, while only a few paid attention to setting of subgoals. In addition, although teachers attended to student's formulation of equations, only a few attended to the deriving physical quantities using alternative approaches. Teachers who did not consider the understanding stage relied on subjective reasoning and provided interpretations that lacked sufficient evidence, while their instructional responses to promote the identification of conditions and the setting of subgoals were generally superficial when suggested. In contrast, among the teachers who considered the understanding stage and distinguished student's problem-solving process into understanding and planning stages offered interpretations based on valid evidence and proposed instructional responses that linked the identified conditions and goals to the planning stage. Some teachers proposed instructional responses that synthesized the related concepts or laws necessary for problem-solving. Additionally, they connected formulating equations and calculation processes to their instructional responses. Based on these findings, we proposed ways to improve teachers' noticing of student's problem-solving process.
Volatile Organic Compounds (VOCs) are significant pollutants emitted during industrial processes, with their release continuously increasing due to rapid industrialization, posing critical threats to environmental quality and human health. Catalytic oxidation is regarded as one of the most effective methods for VOC removal due to its low cost and high elimination efficiency. In pursuit of safety, energy savings, cost-effectiveness, and environmental friendliness, extensive efforts have been devoted to developing efficient catalysts that leverage the synergistic effects of catalysts and reactive oxygen species (ROSs) by incorporating ozone molecules, thereby reducing the temperature required for VOC catalytic oxidation. Based on research into largescale treatment of industrial VOC waste gases, this study proposes an integrated adsorption-catalysis process system that balances cost and efficiency. Waste disposable bamboo chopsticks were recycled as precursors for carbon-based materials, and transition metal manganese oxides with different crystal phases were loaded onto the carbon substrate. The MnOx-BC composite with the highest catalytic activity was selected for the catalytic oxidation of recalcitrant industrial o-xylene.
This study compared entropy descriptions and inquiry-activity structures across Korean high school Chemistry II textbooks aligned with the 2009 revised curriculum, Matter and Energy textbooks aligned with the 2022 revised curriculum, and college-level general chemistry textbooks. We conducted a deductive content analysis with binary coding and frequency summaries, complemented by comparisons of representative passages. The analytic criteria addressed the placement of the disorder metaphor, the presentation and use of the system-surroundings perspective, the inclusion of statistical explanatory elements and thermodynamic definitions and their explicit linkage, and the types, contexts, and process elements of inquiry activities. The results showed that in the 2022 revised textbooks, where Gibbs free energy is not introduced, the selection and organization of explanatory elements and the use of the system-surroundings perspective varied across publishers, whereas the disorder metaphor persisted mainly in definitions and examples. Inquiry activities increased overall, but quantitative experiments and calculations decreased, shifting toward data interpretation, discussion, and project-based tasks. These patterns suggest that presenting explanatory elements as separate components without explicit connections may place greater demands on students as they transition to college general chemistry, where explanations are typically more integrated. Accordingly, we propose that textbook descriptions and task designs explicitly connect statistical and thermodynamic perspectives through system-surroundings reasoning and require students to apply these connections in justification tasks.
This study analyzes the structure, content, and linguistic features of Sinpyeon Hwahak ((sic)(sic)(sic)(sic)), a chemistry textbook published in 1907, to explore its significance in the history of Korean science education. Compiled by Ahn Hyeong-jung and edited by Hyun Gong-ryeom, it represents an early attempt to introduce modern chemistry during the Korean Empire period. The textbook systematically presents basic chemical concepts such as elements, molecules, and reactions in Part I, and applies them to practical chemistry in Part II. It employs a logical conceptual sequence and Sino-Korean terminology familiar to learners. Linguistically, it shows a transitional mixture of Sino-Korean terms, Japanese translation patterns, and Korean explanations. The use of 42 figures and 24 tables reflects an integrated approach linking theory, experiment, and practice. Sinpyeon Hwahak thus provided a foundation for modern chemical education in Korea.
This study explored secondary science teachers' awareness of and ability to implement learning objectives. A questionnaire consisting of three areas - recognition, setting, and implementing learning objectives - was developed and administered to teachers, who were then categorized as beginning or experienced. The results showed that, regardless of their experience, most teachers recognized the importance of learning objectives and utilized them in lesson design and implementation. However, they valued curriculum concepts more than learning objectives and were more likely to present learning objectives directly. Experienced teachers were more likely to focus on the curriculum, set their own learning goals, and use student achievement of learning goals to inform the design of the next lesson. In contrast, beginning teachers were less likely to set learning objectives. They organized their lessons around textbooks and used learning objectives primarily for feedback. They also tended to prefer teacher-centered lessons due to difficulty dealing with various situations that may arise in class and lack of time. They were more likely to present learning objectives clearly and directly in class and less likely to allow students to find their own.
This study aimed to examine the characteristics of learning objectives established by pre-service secondary science teachers during lesson planning and implementation and how these objectives were reflected in actual classroom instruction. Twentyfour fourth-year students majoring in chemistry education at a college of education participated in this research. Data included lesson plans, teaching videos and interviews, which were analyzed qualitatively. The analysis identified two distinct types of perceptions regarding learning objectives. Differences in these perceptions were associated with variations in the coherence between learning objectives and other instructional components when designing and implementing lessons. Most learning objectives were formulated based on textbooks and teacher guides with a predominant focus on 'knowledge and understanding' while objectives related to 'processes' or 'attitudes' were rarely included. In lesson implementation, five types of instructional patterns were identified based on the manner in which learning objectives were introduced and shared with students. However, the overall alignment between learning objectives and assessment practices was found to be weak. These results suggest that while pre-service teachers are aware of the importance of objective-centered lesson design, they face challenges in applying this understanding consistently across all instructional components.
We systematically investigate the photophysical properties of positional isomers of dinaphthyl anthracenes (ADNs) in toluene. Among three ADNs, progressive red-shifting and vibronic broadening in steady-state absorption and emission spectra with increasing 2-substitution indicate changes in effective electronic delocalization and conformational heterogeneity. The fluorescence intensity increases modestly from 1,1-ADN to 2,2-ADN, reflecting the sensitivity of emissive properties to substituent orientation. Femtosecond transient absorption spectroscopy reveals pronounced isomer-dependent excited-state dynamics. Although the excited-state absorption (ESA) features remain largely comparable, the ground-state bleaching and stimulated emission (GSB/SE) signals exhibit significant variations in intensity and kinetics. Particularly, isomers with stronger GSB/SE signals display a distinct rise component on the tens-of-picoseconds timescale, consistent with the gradual formation of a more emissive excitedstate configuration. These results establish a direct link between substituent geometry and excited-state relaxation pathways, providing insights into the molecular design of anthracene-based emissive materials for OLED applications.
. The photo-Fenton-like degradation of pollutants is dependent on the pH of solution. Here, we synthesized pristine ZnO nanorods, silver nanoparticle (AgNPs), and Ag-decorated ZnO (Ag/ZnO) composites. These materials were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and UV-visible (UV-vis) spectroscopy. Their catalytic activities were evaluated for the photo-Fenton-like degradation of 4-nitrophenol (4-NP) under visible-light irradiation at pH 4 and 7. Pristine ZnO nanorods exhibited higher catalytic activity than the Ag/ZnO composite at pH 4, while this trend reversed at pH 7. This pHdependent reversal is attributed to the interplay between the catalyst's surface charge and the speciation of 4-NP into its phenolate form. These findings demonstrate that the key factor for enhanced photocatalytic performance is not the noble metal decoration itself, but rather the interfacial charge and dominant reactive species.
The current study was presented a plain, and highly sensitive to remove Pd (II) from wastewater. A modified magnetic multiwall carbon nanotubes with chitosan (Methionine-Chi/MWCNTs-COOH/Fe3O4) was created. Through coordination and chelation with the -NH2, -COOH, and -S groups of methionine/chitosan, it achieved 170.5 mg g(-1) capacity via chemisorption (pseudo-second-order kinetics) using CCD optimization (pH 6.0, 48 mg adsorbent, 15 min contact time, 11 mL eluent). Pd (II) can be effectively removed from actual industrial effluents using this spontaneous and exothermic process. The results indicated that the Langmuir model offered a superior fit for the isotherm data when compared to models of the Freundlich and Temkin. Additionally, the kinetic data showed excellent agreement with the model of pseudo-second-order adsorption. Both physical and chemical adsorption processes were involved, as shown by the negative Delta H values. Overall, the results indicate that Methionine-Chi/MWCNTs-COOH/Fe3O4 exhibits strong potential as an adsorbent material for selective Pd (II) removal from industrial effluents.
This study investigated the effects of the "elementary science inquiry education" course on pre-service elementary teachers' orientation toward scientific inquiry teaching and the factors of the teaching-learning experience of the course that affected the orientation. To do so, 45 second-year students (11 males and 34 females) taking the course at a university of education were surveyed about their orientation toward scientific inquiry teaching before and after taking the course. In addition, the experience factors that influenced their orientation toward scientific inquiry teaching were examined after the course, and individual in-depth interviews were conducted with some students. The results showed that before the course, the most common orientation toward scientific inquiry teaching was "scientific practice", followed by "concept understanding" and "complex". In particular, "complex" was mainly a mixture of "concept understanding" and "scientific practice". "Process skills", "activity driven", and "engineering practice" were very rare. After taking the course, "complex" was the most common, followed by "scientific practice". While "complex" was still dominated by a mix of "concept understanding" and "scientific practice", there were some new mixes that did not appear before the course. "Concept understanding", "activity driven", "process skills", and "engineering practice" were very rare. By type of change in orientation toward scientific inquiry teaching, "simple -> complex" was the most common, and "simple -> simple" was the second most common. Many pre-service elementary teachers selected "preparing for science class demonstration", "mentoring from a professor in preparing for science class demonstration", "conducting science class demonstration", "mentoring from a professor after conducting science class demonstration", "learning theories about science learning models", "participating in science classes as a learner", "peer discussion and feedback on science class demonstration", "learning theories about process skills", "learning theories about the nature of science", and "analyzing science textbooks" as experience factors that influenced their science inquiry teaching orientation.
This study developed an educational program that integrates AI and data science into chemistry teaching using the no-code machine learning platform Orange3 and examined its effects with 20 in-service chemistry teachers. The program was designed to provide hands-on experience across the entire process of data collection, preprocessing, visualization, and modeling. Quantitative analysis revealed significant improvements in all subdomains of data literacy and in teachers' individual AI teaching efficacy. Qualitative analysis identified three key themes: (1) a shift in perception of AI from an expert-exclusive domain to a universally accessible tool, (2) the enhancement of chemistry concept understanding through Orange3's visualization features, and (3) the strengthening of teachers' practical willingness to apply data-driven lessons to students. These findings suggest that no-code AI tools can expand teachers' instructional competencies and contribute to innovation in data-driven science education.
. The objective of this study is to develop a production technology for polymer gel-type moisture-retaining complex fertilizers by neutralizing the FER-PANS MCD polymer reagent, formaldehyde, and inorganic acids along with mineral components using nitric acid or sulfuric acid. The parameters for synthesizing gel-like substances based on the FER-PANS MCD polymer reagent, cross-linking agents, and inorganic and organic acids were investigated. The consumption norms of formalin, citric acid, and inorganic acids required for gel formation were determined by analyzing their correlation with gelation time and swelling parameters. Based on experimental studies, moisture-retaining complex fertilizers were synthesized by incorporating the mineral component MAP in varying ratios into the optimally selected formulations. The key physicochemical characteristics of the synthesized complex fertilizers were examined using IR spectroscopy, SEM analysis, thermal analysis, and swelling capacity assessment. SEM analysis of the obtained moisture-retaining complex fertilizers revealed that the MAP-containing variant comprised essential plant nutrients, including O (52.59%), P (18.11%), Ca (0.04%), K (0.11%), Fe (0.03%), and S (0.03%). Additionally, the swelling capacity of the fertilizer, which indicates its moisture retention ability, was found to range from 26% to 36.5%.
This study aims to explore changes in the teaching orientations of four high school chemistry teachers in a professional learning community (PLC) focused on scientific inquiry using digital tools. Data was collected through pre-and post-PLC questionnaires, interviews, and PLC discussions. Analysis across three subcomponents, i.e., beliefs about the nature, goals, and teaching-learning of scientific inquiry using digital tools revealed that teacher orientation remained stable, newly emerged, elaborated, expanded, adjusted or narrowed after teacher activities in PLC. These changes seemed to occur through reconstructing the meaning of scientific inquiry using digital tools based on teacher beliefs about science and scientific inquiry, developing goals for teaching scientific inquiry using digital tools, and reorganizing the structure and process of teaching and learning. The findings suggest that PLC activity, classroom practice, teacher and school learning context, and teacher-student interaction collectively shape and transform teaching orientations toward scientific inquiry using digital tools.
In this study, an educational program utilizing decision trees was developed and applied to improve chemistry teachers' metamodeling perceptions regarding oxidation-reduction reaction models. The participants included 23 chemistry teachers enrolled in a master's program at a comprehensive teacher training university. The program was conducted online over three sessions, each lasting four hours, for a total of 12 hours. The educational program consisted of six stages: concept verification and motivation regarding the electron transfer model, oxidation state change model, and bond type change model (Goodstein model); exploration of AI tool functions using the Orange3 program; generation of concept-based data for each model; concept refinement through AI modeling; AI-based error diagnosis and evaluation; and reflection and sharing. Teachers generated information about chemical reaction equations to create a decision tree classification model, identified the causes of classification errors through the decision tree when machine learning indicated errors, and corrected misconceptions independently. To analyze the effectiveness of the program, changes in teachers' values regarding oxidation-reduction reaction models, model-based judgment capabilities, and perceptions of scientific metamodeling were examined through pre-and post-surveys. The results indicated that teachers' values regarding oxidation-reduction reaction models shifted from a hierarchical perspective to a pluralistic perspective, and they developed a higher-level judgment capability to clearly recognize the scope and limitations of the models. In particular, the perception of scientific metamodeling progressed from the level of objective explanatory tools (Level 2) to the level of exploratory and pluralistic tools (Levels 3 and 4). AI tools were utilized as effective teaching and learning instruments that facilitated teachers' metacognitive reflection. Teachers had positive learning experiences through immediate error identification and visualization, promotion of collaborative discussions, and enhancement of metacognitive reflection. These results suggest that inquiry experiences utilizing AI are effective in deepening teachers' understanding of the nature of science and leading to changes in their practical teaching strategies. Therefore, it is essential to continuously develop and expand professional development programs centered on inquiry experiences where teachers construct and evaluate scientific models themselves using AI tools. This will enable chemistry teachers to deeply understand the nature of models and design lessons that foster the scientific thinking and inquiry skills required by future society.
This study examines the types of inquiry activities and the levels of digital tool utilization in the Material units of elementary science textbooks developed under the 2022 revised science curriculum. The results indicate that Experiment and Observation (EO) accounted for the highest proportion (62.4%), followed by Investigation, Discussion, and Presentation (IN) (15.6%) and Expression (EX) (12.1%). In contrast, Discussion and Debate (DE) was absent, and Data Interpretation (ID) accounted for only 3.5%. Digital tools were used in 59.9% of inquiry activities, with Auxiliary Digital Inquiry (AD) being the most common (45.3%), followed by Central Digital Inquiry (CD) (13.4%). Fully Digital Inquiry (FD) had the lowest proportion (1.2%). These findings suggest the need for curriculum development that incorporates diverse inquiry activities, professional training to enhance discussion-based science inquiry instruction, and strategies for effective digital tool integration in inquiry-based learning.
Based on the magnetic properties of commercial cathode material (LiNixMnyCo1-(x+y)O2) for lithium-ion batteries, we have developed a technique utilizing magnetic fields to orient crystal structures, aligning the lithium-ion transfer direction perpendicular to the electrode surface across the entire electrode assembly. Through measurements and analysis of the magnetic properties of the commercial cathode material, we theoretically examined the required magnetic field strength for crystal orientation and secured a technique for crystal orientation using magnetic fields achievable in conventional electromagnets (approximately 1 Tesla (T)). This technique demonstrated comparable crystal orientation and electrochemical performance enhancement to the previous technology developed by our research group using strong magnetic fields (3 T). By validating the effectiveness of crystal orientation of commercial cathode materials at lower magnetic fields theoretically and experimentally, we aim to enhance the industrial applicability of related technologies.
