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Pedagogical Content Knowledge (PCK) is crucial for effective teaching, but it is a complex and implicit knowledge, especially in chemistry education. Therefore, this study explores the use of the LBCD (Learning by Collaborative Design) model to support PCK development among pre-service chemistry teachers. This study adopted a one-group pretest-posttest experimental design, conducting the intervention with 210 participants. After data collection, the study first conducted exploratory and confirmatory factor analyses on the pre-and post-test data, confirming the good reliability and validity of the designed chemistry PCK questionnaire. Additionally, paired sample t-tests were used to measure pre-service teachers' PCK development in dimensions of CTO, KOA, KOC, KOL, and KOS. Furthermore, unstructured interviews helped to further clarify the participants' views of the effectiveness of the LBCD curriculum. The results showed that the developed chemistry PCK questionnaire and the LBCD model had a significant statistical impact on the PCK elements development among pre-service teachers, although the development of these elements was not balanced. Finally, the study provides suggestions for the measurement of PCK elements, as well as chemistry teacher education, such as applying the LBCD model to different teacher groups and testing PCK element models using the methods of this study.

This study utilized the SEC (Survey of Enacted Curriculum) method to examine the alignment between Chinese high school chemistry curriculum standards (HSCCS) and the assessment of 'Chemical Reaction Principles' in the National College Entrance Examinations (NCEEs). The HSCCS and NCEEs were coded into two-dimensional matrices separately using SPSS, MATLAB, and EXCEL. The alignment coefficients were analyzed both macroscopically and specifically based on two dimensions: themes and cognitive levels. The findings indicated a generally low alignment between NCEEs and HSCCS in the 'Chemical Reaction Principles' domain, and no statistically significant alignment was observed. Comparing Porter alignment coefficients revealed a gradual increase in the overall alignment level between 2018-2022 NCEEs and HSCCS due to curricular reforms. Further specific analyses and comparisons highlighted significant discrepancies between NCEEs and HSCCS concerning themes and cognitive levels. Regarding themes, 'Ionic Reactions and Equilibrium in Aqueous Solutions' showed substantial alignment between NCEEs and HSCCS. However, for 'Application of Ionic Reactions and Equilibrium' and 'Systems and Energy,' NCEEs diverged significantly from or exceeded HSCCS requirements. Concerning cognitive levels, NCEEs demanded higher levels of student cognition compared to HSCCS.

Active participation in project-based learning (PBL) could develop students` knowledge and crucial learning skills across various disciplines. However, the implementation of PBL in the K-12 classroom is usually impeded by the stepby-step PBL cycle. Micro project-based learning (MPBL), which advocates and adheres to the learning principles and mechanisms of PBL with constraining the learning cycle in shorter periods, has been considered as a lightweight alternative to PBL process. As an exploration, this study explored the impact of MPBL on the conceptual understanding of sodium bicarbonate and the crucial learning skills in chemistry class at upper-secondary schools. The quasi-experimental research was implemented for 125 students, with an experimental group receiving MPBL teaching and a control group receiving conventional teaching. In the study, data including knowledge tests, crucial learning skills survey, and student interview were collected and analysed. The results indicated that MPBL was effective in the development of students' conceptual understanding and crucial learning skills (i.e., communication and collaboration, information integration, independent learning, and problem-solving). The study will inform the pedagogical innovation in chemistry education and teaching practices in chemistry class.

In upper-secondary chemistry education, the concept of 'Amount of Substance' occupies a central position within the computation framework. However, comprehending this concept often poses a challenge for students. To address this issue, our study aimed to design and implement a computation skills test to assess the varying levels of students' computation skills in understanding Amount of Substance. The test was administered to a total of 214 first-year students at the secondary schools. To analyse the test scores and unveil students' comprehensive and mastery levels of computation skills, the SOLO Taxonomy was employed for scoring the levels. Additionally, interviews were conducted to identify the underlying reasons for their learning difficulties. Findings revealed that the majority of students demonstrated proficiency in solving relatively straightforward problems and applying basic formulas. Only a small fraction of students reached the advanced relational level, showcasing their ability to apply chemical concepts and methodologies to solve complex problems. Moreover, students exhibited varying degrees of proficiency when dealing with different types of knowledge and problems associated with computations involving solutions and the quantification of microscopic particles. Interviews uncovered students' major learning difficulties. These findings inform the teachers' teaching of Amount of Substance in chemistry education.

Level 3 characteristics are increasingly important for fingerprint identification, particularly when the fingerprints are problematic and lack level 2 details. In practice, no reliable visualization methods for level 3 features are transferred into a course for the general public, forensic students, or investigators. Our group has reported the membrane/water technique and wet-membrane method as simple, instantaneous, high-resolution, and reproducible methods for visualizing level 3 features of latent fingerprints (LFPs). Herein, we designed a simple-to-operate laboratory course on sweat pore visualization and analysis via the two methods mentioned. Three modules are included, and students participate in different modular combinations according to their interests and specialties. Module 1, consisting of a 15 min lecture on fingerprint theory followed by a brief demonstration of visualization procedures, is designed for broad audiences ranging from primary school to college laboratories. In module 2, students explored the deposition force impact on level 3 features (for students majoring in forensic science). Module 3 customized for forensic upper-division undergraduates and postgraduates invites them to conduct Gaussian fitting of the pore area and adjacent pore distance. After discussion, students form their own opinions on the identifiable strengths of the above parameters in fingerprint matching. In a way, this experiment can be evolved into the elective course and specialized curriculum, where elective course containing module 1 can stimulate public interest in chemistry and specialized curriculum including modules 1-2 (or modules 1-3) may guide students to extract level 3 features and understand the role of level 3 features at a quantitative level.

A comprehensive laboratory-style teaching activity involving the synthesis, characterization, and analysis of structure-activity relationships of metal-organic framework (MOF) nanozymes was developed specifically for undergraduates at Tianjin University. The students acquired familiarity with the general approach in synthesizing MOFs by solvothermal method using substituted MIL-101­(Fe)-X (MIL is an acronym for Materials of Institute Lavoisier). Several modern characterization methods were taught, including powder X-ray diffraction and fluorescence spectroscopy for assessing MIL-101­(Fe)-X crystal structures and superoxide dismutase (SOD)-like activities. In particular, students were guided by the instructor to investigate the relationship between structural differences in MOFs caused by ligand changes and their SOD-like activities. The Hammett relationships were later demonstrated to be an accurate method of quantifying structure-activity relationships of MIL-101­(Fe)-Xnanozymes. By participating in this laboratory experience, students are able to improve their scientific thinking, practical abilities, and teamwork. Additionally, a fundamental principle of material design can be conveyed to undergraduates based on the structure-activity relationship, thereby deepening their understanding of nanozymes and the course's content.

Current science elective courses in Chinese high schools overemphasize subject knowledge, lack course resources, and apply a single instruction methodology. This study attempts to reform high school elective chemistry courses and aims to promote chemical science literacy in students. It takes the example of the development and practice of elective courses titled "The Mysteries of Chemistry in Intangible Cultural Heritage". This course encompasses seven chemical themes closely related to health and safety, environmental protection, and social development: combustion, compounds, aqueous solutions, metallic materials, nonmetallic materials, biomacromolecules, and natural resins. The course contents are combined with the human intangible cultural heritage to stimulate student interest by incorporating a rich experience of the chemical sciences. The course focuses on experiential learning processes and employs student-centered situational teaching and project-based learning, combining experimental learning, class discussions, and reflective essay writing. The study results reveal that the course improves academic performance and enhances student interest and self-efficacy in chemistry learning; it also provides students with continuous help in engaging in the safeguarding and inheritance of their intangible cultural heritage and substantially develops scientific literacy.

The continuous distillation experiment in the Unit Operations Lab was moved to a virtual platform. Students used old data and equipment specifications to simulate the column in Aspen HYSYS. Students experimented without the limitations of existing equipment. For example, they studied the number of trays in the virtual column, something that is impossible with the physical set-up. In this work, we present the outline for the module and discuss student experiences and feedback.

For chemistry, where learners are required to integrate experimental observations with theoretical knowledge, laboratory work appears to be a viable instructional strategy. However, research has shown that chemistry laboratory instruction often fails to live up to its potential. The scheduling practice in higher education (HE) separating theory lessons and practical work into temporally disjointed sessions could exacerbate the theory-laboratory disconnect. This paper continues an earlier work, in which integrated schedules of chemistry tutorial and laboratory classes were implemented in two general chemistry courses in a freshman chemical engineering programme. Traditionally separate tutorial and laboratory classes were chained into 3 hour blocks in the experimental classes. Worked examples, group presentations and course materials designed as a merged package to connect theory with practical work were implemented for selected tasks in integrated teaching. Prior ability was measured based on previous titration experience or grades in earlier general chemistry courses. Lesson experiences were collected on the validated Meaningful Learning in the Laboratory Instrument (MLLI) (Galloway and Bretz, 2015). Block (or integrated) and traditional learners performed equally on theory tests, but integrated learners scored higher on a titration skills assessment. The origin of differences in skills performance could not be ascertained conclusively. Perceptions across the MLLI domains declined across schedules, with significant losses in the cognitive domain. MLLI scores did not differ by schedules. There is some evidence favouring stronger theory-laboratory connection from the qualitative MLLI data and the focus group interviews, although cognitive overloading may adversely impact low ability learners. This work showed that block scheduling does not affect the chemistry skills-set equally, which opens the topic for future research. Suggestions for future implementation of chemistry block teaching were also proposed.

The development of the skills to read and understand scientific literature is crucial to the future success of students. A literature review project was introduced into an organic chemistry laboratory course, in which undergraduate students were asked to acquire the skills of scientific literature searching, reading, and summarizing. The course project was improved during the COVID-19 pandemic, and a step-by-step study schedule in 7 weeks was carried out. The students wrote and handed in their reviews successfully through the training process. The literature review helped the undergraduate students to get a further comprehensive understanding of the relationship between organic chemistry and medical science.

A new type of bismuth selenide nanosheet layer material was synthesized by solvent thermal method, which is harmless to human body and can be used in combination with hydrogen peroxide solution as a new type of modern insecticide. The particle size of the bismuth selenide nanosheet material is about 80 nm, and it has good dispersion in water. In this experiment, the antibacterial ability of the material was investigated using Escherichia coli and Staphylococcus aureus as bacterial models and plant pathogens such as strawberry gray mold and tomato gray mold as fungal models. In addition, the in vivo bioassay indicated that Bi2Se3+H2O2 possessed effective control against Pepper Anthrax Disease. The biocompatibility of this material was also investigated using human umbilical vein endothelial cells (HUVEC) as a model, and the results showed that the bismuth selenide nanosheet material has good antibacterial ability and biocompatibility.

Abstract Predicting protein-small molecule binding sites, the initial step in structure-guided drug design, remains challenging for proteins lacking experimentally derived ligand-bound structures. Here, we propose CLAPE-SMB, which integrates a pre-trained protein language model with contrastive learning to provide high accuracy predictions of small molecule binding sites that can accommodate proteins without a published crystal structure. We trained and tested CLAPE-SMB on the SJC dataset, a non-redundant dataset based on sc-PDB, JOINED, and COACH420, and achieved an MCC of 0.529. We also compiled the UniProtSMB dataset, which merges sites from similar proteins based on raw data from UniProtKB database, and achieved an MCC of 0.699 on the test set. In addition, CLAPE-SMB achieved an MCC of 0.815 on our intrinsically disordered protein (IDP) dataset that contains 336 non-redundant sequences. Case studies of DAPK1, RebH, and Nep1 support the potential of this binding site prediction tool to aid in drug design. The code and datasets are freely available at https://github.com/JueWangTHU/CLAPE-SMB . Scientific contribution CLAPE-SMB combines a pre-trained protein language model with contrastive learning to accurately predict protein-small molecule binding sites, especially for proteins without experimental structures, such as IDPs. Trained across various datasets, this model shows strong adaptability, making it a valuable tool for advancing drug design and understanding protein-small molecule interactions.

The Tibetan Plateau (TP) is highly susceptible to climate change, and nitrogen-containing organic compounds (NOCs) in fine particulate matter (PM2.5) represent one of the largest uncertainties with respect to their impact on the climate in high-altitude areas. Previous studies have shown that NOCs play a vital role in the nitrogen budget of PM2.5. However, our understanding of the composition and sources of NOCs in PM2.5, particularly in the TP, is limited. Here, we aim to enhance our understanding of NOCs in the TP region by examining their identification, concentration levels, sources, and origins. We conducted field sampling at a regional background sampling site in Gaomeigu, in the southeastern margin of the TP from 11 March to 13 May 2017, followed by laboratory analysis of the NOCs collected on the filters. The daily mass concentrations of NOCs ranged from 714.4 to 3887.1 ng m−3, with an average of 2119.4 ± 875.0 ng m−3 during the campaign. This average concentration was approximately 40 % higher than that reported at a typical regional site in the North China Plain (NCP), highlighting a more significant presence of NOCs in the Tibetan area. Biomass burning and secondary sources were identified as the major contributors to total NOCs. This was further substantiated by a regional air quality model, which indicated that over 80 % of the aerosol in the southeast of the TP originated from neighboring countries. This study improves our understanding of NOCs' contribution to PM2.5 in the TP and their potential impacts on climate stability in high-altitude areas.

Abstract Background superparamagnetic ferroferric oxide (Fe3O4) nanoparticles can be extensively functionalized for applications in drug enrichment and separation. Their high magnetic responsiveness and controllable surface modification enable rapid drug enrichment and separation under external magnetic fields. This study aimed to enhance the application potential of superparamagnetic Fe3O4 nanoparticles in the field of drug enrichment and separation by functionalizing these nanoparticles to improve their biocompatibility and targeting capabilities. Methods superparamagnetic Fe3O4 nanoparticles functionalized with dopamine were synthesized using benzyl alcohol as the solvent and iron acetylacetonate as the precursor. The dopamine-functionalized superparamagnetic iron oxide nanoparticles were used to analyze protein enrichment and separation. Characterization of the nanoparticles was conducted, including analysis of particle size distribution, Zeta potential, and fluorescence spectra using a fluorescence spectrophotometer. Results the Fe3O4 nanoparticles maintained high magnetism from the original material and exhibited uniform particle size distribution and stable Zeta potential. The saturation magnetization of dopamine-functionalized superparamagnetic Fe3O4 nanoparticles showed no significant difference compared to before coating, indicating minimal influence of dopamine on the internal magnetic core of the nanoparticles. The Fe3O4 nanoparticles demonstrated good biocompatibility and stability. Conclusion functionalization of superparamagnetic Fe3O4 nanoparticles significantly enhances their efficiency in drug enrichment and separation processes, suggesting broad applications in the pharmaceutical industry.

The coupling between surface ozone (O3) and vegetation significantly influences the regional to global climate. O3 uptake by plant stomata inhibits the photosynthetic rate and stomatal conductance, impacting evapotranspiration through land surface ecosystems. Using a climate–vegetation–chemistry coupled model (the NASA GISS ModelE2 coupled with the Yale Interactive terrestrial Biosphere, or ModelE2-YIBs), we assess the global climatic responses to O3–vegetation interactions during the boreal summer of the present day (2005–2014). High O3 pollution reduces stomatal conductance, resulting in warmer and drier conditions worldwide. The most significant responses are found in the eastern US and eastern China, where the surface air temperature increases by +0.33 ± 0.87 and +0.56 ± 0.38 °C, respectively. These temperature increases are accompanied by decreased latent heat and increased sensible heat in both regions. The O3–vegetation interaction also affects atmospheric pollutants. The surface maximum daily 8 h average O3 concentrations increase by +1.46 ± 3.02 ppbv in eastern China and +1.15 ± 1.77 ppbv in the eastern US due to the O3-induced inhibition of stomatal uptake. With reduced atmospheric stability following a warmer climate, increased cloud cover but decreased relative humidity jointly reduce aerosol optical depth by −0.06 ± 0.01 (−14.67 ± 12.15 %) over eastern China. This study suggests that vegetation feedback should be considered for a more accurate assessment of climatic perturbations caused by tropospheric O3.

Chemical dyeing and finishing processes used in the clothing and textile industries are among the main contributors that can increase the impact of climate change. Photocatalysis using nanosized titanium dioxide (TiO2) has been continuously developed as a promising technology for purifying dye wastewater into simpler and environmentally friendly components. In addition, the decoration of iron cations (Fe2+) and (Fe3+) increases the reusability of the photocatalyst due to their magnetic properties, which are easy to collect for the recycling process. Magnetic Fex+/TiO2 microfibers have been successfully prepared using a hydrothermal method using titanium dioxide in an alkaline solution. Cations were added into the solution with the different molar ratios of Ti/Fex+ to produce Fe2+/TNW and Fe3+/TNW, respectively. Photocatalysis activity test using magnetic Fex+/TNW was carried out using methylene blue in a reactor equipped with an incandescent bulb lamp representing solar light. The results showed that adding the cations resulted in a new shape of palm tree leaves, like titanate microfibers. Controlling the cation’s molar ratio produces the magnetic Fex+/TNW with a 50-150 µm length. SEM images of each material presented the uniformly elongated shape and aggregated on one side morphology. In addition, paramagnetic properties indicate that magnetic Fex+/TNW can be easily separated from the dispersion in less than 1 minute using an external magnet. A photocatalysis activity test of magnetic Fex+/TNW was performed by calculating the percent degradation of methylene blue with variations in irradiation time in visible light conditions. The result showed the effectiveness of photodegradation of methylene blue was significantly increased in materials with 3.3 molar ratios of both Ti/Fe2+ and Ti/Fe3+ with a percent degradation reaching 79% and 70%, respectively, in 5 hours. In conclusion, magnetic Fex+/TNW is introduced as an alternative dye wastewater treatment technology that has reusable properties and works well on sustainable energy sources of solar light.

Abstract Developing dynamic color‐tunable ultra‐long room temperature phosphorescence (URTP) polymers with afterglow of over 1 s, photo‐chromism, and multi‐stimuli response for practical anti‐counterfeiting and information security applications is attractive but very challenging. Herein, by doping multicolor phosphorescence pyridinium bromide L block or viologen‐based photo‐chromic V block into polyvinyl alcohol matrixes, the water‐stimuli‐responsive color‐tunable URTP polymer films with afterglow of up to 8 s and the reversible viologen‐based photochromic polymer films have been developed. More significantly, a series of dynamic color‐tunable URTP polymer films with ultra‐long afterglow of over 6 s, photo‐chromism, and water‐stimuli response have been successfully exploited by integrating L and V blocks into one polymer system. Mechanistic investigations have revealed that their photo‐chromism mainly comes from the photo‐generated viologen free radicals. Furthermore, their dynamic multilevel anti‐counterfeiting applications have been demonstrated. These results pave the way to develop smarter multifunctional URTP materials for anti‐counterfeiting and optical sensing.

Mandatory use of low-sulfur fuel according to the global sulfur limit regulation has reduced the emissions of SO2 and particulate matter (PM) significantly on ships, and it also leads to a very large uncertainty in volatile organic compound (VOC) emissions. Therefore, an on-board test of VOCs from nine typical cargo ships with low-sulfur fuels in China was carried out in this study. Results showed that the emission factor of VOCs (EFVOCs) varied largely from 0.09 to 3.01 g kg−1 of fuel, with domestic coastal cargo ships (CCSs) having the highest level, followed by inland cargo ships (ICSs) and ocean-going vessels (OGVs). The switch of fuels from heavy fuel oil (HFO) to diesel increased EFVOCs by 48 % on average, which enhanced both O3 and secondary organic aerosol (SOA) formation potential, especially for OGVs. Besides, the use of low-sulfur fuels for OGVs also led to a significant increase in naphthalene emission. These indicated that the implementation of a global ultra-low-sulfur oil policy in the near future needs to be optimized. Moreover, aromatics were the most important common contributors to O3 and SOA in ship exhausts, which need to be controlled as a matter of priority. It was also found that the benzene, toluene, and ethylbenzene ratio of 0.5:0.3:0.2 on average could be considered a diagnostic characteristic to distinguish ship emissions from other emission sources.

Water-insoluble organic carbon (WIOC) constitutes a substantial portion of organic carbon (OC) and contributes significantly to light absorption by brown carbon (BrC), playing pivotal roles in climate forcing. China is a hotspot region with high levels of OC and BrC, but information regarding the sources and light-absorbing properties of WIOC on a national scale remains scarce. Here, we investigated the light-absorbing properties and sources of WIOC in 10 representative urban cities in China. On average, WIOC made up 33.4 ± 7.66 % and 40.5 ± 9.73 % of concentrations and light absorption at 365 nm (Abs365) of extractable OC (EX-OC), which includes relatively hydrophobic OC (WIOC and humic-like substances, HULIS-C) and hydrophilic OC (non-humic-like substances, non-HULIS-C). The mass absorption efficiency of WIOC at 365 nm (MAE365) was (1.59 ± 0.55 m2 (g C)−1) comparable to that of HULIS (1.54 ± 0.57 m2 (g C)−1) but significantly higher than non-HULIS (0.71 ± 0.28 m2 (g C)−1), indicating that hydrophobic OC possesses a stronger light-absorbing capacity than hydrophilic OC. Biomass burning (31.0 %) and coal combustion (31.1 %) were the dominant sources of WIOC, with coal combustion sources exhibiting the strongest light-absorbing capacity. Moreover, employing the simple forcing efficiency (SFE300–700 nm) method, we observed that WIOC exhibited the highest SFE300–700 nm (6.57 ± 5.37 W g−1) among the EX-OC fractions. The radiative forcing of EX-OC was predominantly contributed by hydrophobic OC (WIOC – 39.4 ± 15.5 % and HULIS – 39.5 ± 12.1 %). Considering the aromaticity, sources, and atmospheric processes of different carbonaceous components, we propose a light-absorbing carbonaceous continuum, revealing that components enriched with fossil sources tend to possess stronger light-absorbing capacity, higher aromatic levels, increased molecular weights, and greater recalcitrance in the atmosphere. Reducing fossil fuel emissions emerges as an effective means of mitigating both gaseous (CO2) and particulate light-absorbing carbonaceous warming components.