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In the article, we focus on the stimulation of pupils' experimental activity using escape rooms. The text includes a division of escape rooms into six genres. In one of the genres, we also included the activity of the escape room created by us. By using the escape room we created, we tried to find out whether escape rooms are a suitable tool for stimulating pupils to do experimental activities in physics classes. We conducted a survey with pupils in the third year of an eight-year high school (13-14 years old). The number of pupils varied (18-19) as the survey was conducted over two weeks. We created a questionnaire consisting of seven questions. The questions were about pupil emotional engagement while doing experiments. We determined the suitability of the teaching tool for stimulating pupils using the answers to the questions from the questionnaire, which are related to the stimulation of experimental activity. We also compared the activities - Escape Room and Experiments given by a question using a comparative questionnaire. From the pilot survey, we found that escape rooms stimulate pupils to experiment more than the commonly used experiments given by a question in physics classes.

In astrophysical concepts, a star can be treated as a blackbody. However, teaching blackbody radiation in physics classrooms is not often relevant to astrophysical contexts. Therefore, prospective teacher-students need to have experiences contextualizing blackbody radiation in astrophysics. This study aimed to investigate how the inquiry lesson activities for teaching blackbody radiation in an astrophysics context, including the design of a simple experimental setup and the worksheets. The experimental setup was designed using affordable equipment like a tungsten bulb, a basic meter, a small piece of compact disk, and a smartphone application called lux meter. By manipulating the voltage across the tungsten filament and measuring the current and intensity using a lux meter, students can calculate its temperature, analyze the spectrum through PHET simulation, and construct a graph of wavelength vs intensity. The method of this study combines a qualitative analysis to describe the resulted spectral by the apparatus, lesson design, and description of the implementation. In addition, quantitative analysis using a quasi-experimental one-group pre-test and post-test design was conducted with prospective teacher-student participants who had taken the astronomy course and are still taking the modern physics course. The results show that inquiry lesson using simple apparatus model and materials positively fosters prospective teacher-students understanding of how to contextualize the blackbody radiation concept in astrophysics.

Solid oxide fuel cell (SOFC) systems are spreading worldwide and, for limited applications, also in the transport sector where high power rates are required. In this context, this paper investigates the performance of a six-cell SOFC stack by means of experimental tests at different power levels. The experimental campaign is based on two different stages: the heating phase, useful for leading the system temperature to approximately 750 °C, and the test stage, in which the experimental activities are properly carried out with varying input parameters, such as the DC current load. In addition, a detailed post-processing activity is conducted to investigate the main performance that could be used in the scale-up processes to design and size a SOFC-based system for transportation. The experimental results concern the electrical power, which reaches 165 W, roughly 27 W for each cell and with 52% electrical efficiency, as well as the theoretical thermal power and efficiency, useful for cogeneration processes, with maximum values of 80 W and 25%, respectively, achieved at maximum load. This discussion then shifts to an in-depth analysis of the possible applications of SOFCs in sustainable mobility, particularly in the maritime and aviation industries. The complexities of the issues presented underscore the field’s multidisciplinary nature, ranging from materials science to system integration, and environmental science to regulatory standards. The findings presented could be useful to scientists, engineers, policymakers, and industry stakeholders working on the development and commercialization of SOFC systems in the sustainable transportation sectors.

Recent research advances and technological developments of spouted bed reactors (SBRs) have been discussed in this work. SBR has aroused increasing interest since their invention in 1955 due to its flexibility in processing different feedstocks and the high process yields that can be achieved due to its characteristic fluid dynamics. However, even though highly satisfactory results have been obtained at the laboratory scale for different applications (i.e., drying or thermochemical reactions, among others), their full implementation at an industrial level is still scarce, mainly due to the challenges encountered for their scale-up. In this work, an initial short description of SBR and configurations is followed by a review of the main experimental activities that have been conducted at different scales in the period 2013–2023. Advanced solutions such as multi-unit reactors and the use of rectangular geometries instead of the classical cylindrical ones have arisen as potential areas for further study and development to achieve a reliable implementation of the spouted bed technology at an industrial scale.

The aim of this work was to assess the capability of a hydraulic bottle jack to control vibrations and the effects of earthquakes. The first stage of the present investigation focused on determining the axial stiffness of the apparatus, in order to relate its behavior to that of a linear elastic element. To do this, uniaxial compression tests were carried out using a manually controlled servo system. In the second stage, a conceptual application based on the field of mechanical vibrations was considered. The experimental results confirmed the hypothesis of linear behavior and showed that the stiffness coefficient had distinct values of magnitude that depended on the cylinder height. Simulations were conducted in which the frequencies and the peak displacements of an idealized SDOF system subjected to earthquake excitation were adjusted based on the experimental stiffness. It was possible to conclude that the equipment analyzed here is an effective tool for controlling vibration and reducing displacement during a seismic event, and can be calibrated according to the specific conditions of operation. This is an important aspect of safety and functionality for mechanical and structural systems.

Baccharis dracunculifolia has been used in popular medicine because of its bioactive properties, which include anti-inflammatory, antiulcerative and hepatoprotective potentials. A 2³ central composite rotational design was used to define the best conditions for extracting the bioactive compounds from the leaves of Baccharis dracunculifolia. The parameters studied included the solvent concentration, time and temperature of extraction and the influence of these on the total phenolics content and antioxidant activity. The best conditions were 95 % methanol (v/v), 20 min extraction time, and 70 °C temperature. Under the optimized conditions, high contents of total phenolic compounds (72.5 mg GAE g-1) and high DPPH (865.6 µmol TE g-1) and ABTS (331.11 μmol TE g-1) free radical scavenging capacity and a high ferric reducing antioxidant power (1558.00 μmol FeSO4.7H2O g-1), were obtained. The extract also showed promising anti-microbial activity, demonstrating fungistatic action against C. tropicalis and C. albicans (5 mg mL-1 and 7 mg mL-1, respectively) and bacteriostatic effect against Escherichia coli (60 e 70 mg mL-1), Salmonella enterica typhimurium (40; 60 and 70 mg mL-1) and Staphylococcus aureus (4 mg mL-1). HPLC-DAD analysis showed an extract rich in the phenolic compounds catechin (0.659 mg g-1), caffeic acid (1.135 mg g-1), p-coumaric acid (0.772 mg g-1), ferulic acid (6.24 mg g-1), pinocembrina (0.155 mg g-1) and rutin (0.037 mg g-1).

School experiments represent a necessary means of subject-matter presentation in chemistry education and are important for chemical (scientific) thinking. Despite being a focus of several texts, a complex view on the experimental activity in chemistry education in Czechia is missing. The results of a questionnaire survey among 466 lower-secondary, lyceum and grammar school teachers focused on types of conducted experiments, their frequency, the place they are conducted. The most frequently used chemicals and sources of inspiration are presented in the paper. The results show that despite experiments’ significant role in education, its occurrence is rather seldom and teacher’s demonstrations prevail over students’ experiments. The list of the most often used chemicals suggests the experiments are mostly focused on inorganic chemistry. These results open further questions regarding occupational safety at schools as an important factor which could also be the reason for such a low representation of experiments in Czech chemistry education.

The goal of this study is to develop a clean and efficient thermal unit for a generator set (gen-set) rated at 80 kW, exploring the potential of Dual-Fuel (DF) combustion (Natural Gas-Diesel) on high-speed Compression Ignition (CI) engines. Typically, the most comparable commercial gen-sets are made up of Heavy-Duty (HD) Diesel engines, whose cost and complexity will probably increase to meet more stringent emissions standards. The conversion of a light-duty Diesel engine may permit to match the high efficiency of Diesels with the low emissions of DF combustion at an affordable cost. Moreover, the new thermal unit would be more compact and lighter. Running on Natural Gas (NG) is less expensive than using Diesel fuel, and it offers more opportunities to reduce the environmental impact (e.g., NG can be easily obtained from biomass, in the same site where the gen-set is installed). Last but not the least, in case of interruption of NG supply, the system can be easily switched to conventional Diesel operation, offering a higher fuel flexibility. Despite the large number of scientific publications concerning DF engines, very few of them consider high-speed units equipped with modern Common Rail injection systems. Even more limited are the investigations on the combustion process at medium-high loads (BMEP > 10 bar), carried out by measuring in-cylinder pressure and optimizing all the fundamental control parameters (injection strategy for both Diesel fuel and NG, boost pressure, EGR rates, etc.). It should be observed that the use of state-of-the-art injection systems and the accurate calibration of their parameters at each operating condition is the only way to maximize the benefits of NG in terms of reduction of soot emissions while addressing the well-known issues related to the increase of some pollutants (HC, CO, and NOₓ). This study reviews the results of a theoretical and experimental activity carried out on a four-cylinder, Common Rail, 2.8-liter turbocharged Diesel engine. A gas injection system is installed upstream of the intake plenum, and an open Electronic Control Unit (ECU) is used to calibrate all the most important engine parameters. Thanks to the deep insight into the combustion process provided by in-cylinder pressure analysis and measurement of pollutant emissions, the study presents some general guidelines for setting the control strategy in this type of DF engine. Considering the operating condition at maximum power (BMEP = 12 bar, 3000 rpm, brake power = 83 kW), the following advantages are observed with comparison to the standard Diesel engine: soot is more than halved, NOₓ emissions are reduced by 32% and CO₂ by 31%, and Brake Thermal Efficiency (BTE) increases from 35.8% to 39%. The only drawback is the increase of one order of magnitude of both CO and HC, requiring a specific oxidation catalyst. Another outcome of the study is the limitation on the use of DF NG-Diesel combustion at low loads: the experimental activity demonstrates that it is very difficult to achieve complete combustion of an ultra-lean air-NG premixed charge so that BTE tends to drop. At these conditions, it appears to be more convenient to switch back to standard Diesel operations.

Aim: Experimental models are a powerful aid in visualizing molecular phenomena. This work reports how the worm Caenorhabditis elegans (C. elegans) can be effectively explored for students to learn how molecular cues dramatically condition axonal guidance and define nervous system structure and behavior at the organism level. Summary of work: A loosely oriented observational activity preceded detailed discussions on molecules implied in axonal migration. C. elegans mutants were used to introduce second-year medical students to the deleterious effects of gene malfunctioning in neuron response to extracellular biochemical cues and to establish links between molecular function, nervous system structure, and animal behavior. Students observed C. elegans cultures and associated animal behavior alterations with the lack of function of specific axon guidance molecules (the soluble cue netrin/UNC-6 or two receptors, DCC/UNC-40 and UNC-5H). Microscopical observations of these strains, in combination with pan-neuronal GFP expression, allowed optimal visualization of severely affected neurons. Once the list of mutated genes in each strain was displayed, students could also relate abnormal patterns in axon migration/ventral and dorsal nerve cord neuron formation in C. elegans with mutated molecular components homologous to those in humans. Summary of results: Students rated the importance and effectiveness of the activity very highly. Ninety-three percent found it helpful to grasp human axonal migration, and all students were surprised with the power of the model in helping to visualize the phenomenon.

The inspection of underwater structures is often hampered by harsh environmental conditions, limited access, high costs, and inherent safety issues. This paper focuses on the use of an underwater rover to implement automated imaging techniques for facilitating inspections. The application of such techniques can significantly improve the state of monitoring, reduce operational complexity, and partially offset the financial burden of periodic inspections. To date, there has been very little work on image-based techniques for detecting and quantifying the extent of structural damage, particularly in the submerged part of marine structures. This work seeks to address this knowledge gap through the development and performance evaluation of underwater photogrammetry. The development of the research has been carried out using the FIFISH V6 rover with the Brave 7 camera, which has all the characteristics required for successful photogrammetry. To connect the sensor to the rover, a support was designed accordingly. Finally, experimental photogrammetry tests of an anchor were carried out and compared, both in and out of the sea environment, to validate the model presented. The results obtained so far confirm the validity of the proposed approach and encourage the future development of this apparatus for underwater inspections.