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A novel layered zincophosphate (ZnPO–MPA) was prepared by hydrothermal crystallization using 3-methylaminopropylamine (MPA) as a structure-directing agent. The structure consists of macroanion [Zn2P3O8(OH)3]2- layers which are built up of 4-membered ring channels. The channels (of about 3.7 Å diameter) arise through the connection of the neighbouring rings by two oxygen bridges. The negative charge of the layers is compensated by diprotonated MPA molecules which are stacked parallel to the ring channels. ZnPO–MPA is stable up to 300 °C. At higher temperatures MPA decomposition begins followed by a dehydration, which occurs through condensation of the framework hydroxyl groups. The activation energy of the MPA decomposition is high due to the fact that the layers and MPA cations are held together by strong hydrogen bonds.

This study aimed to prepare a facile hierarchical aluminium surface using a two-step process consisting of chemical etching in selected concentrations of CuCl2 solution and surface grafting through immersion in an ethanol solution containing 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane. The goal was to achieve superhydrophobic characteristics on the aluminium surface, including enhanced corrosion resistance, efficient self-cleaning ability, and improved anti-icing performance. The surface characterisation of the untreated aluminium and treated in CuCl2 solutions of different concentrations was performed using contact profilometry, optical tensiometry, and scanning electron microscopy coupled with energy dispersive spectroscopy to determine the surface topography, wettability, morphology, and surface composition. The corrosion properties were evaluated using potentiodynamic measurements in simulated acid rain solution and salt-spray test according to ASTM B117-22. In addition, self-cleaning and anti-icing tests were performed on superhydrophobic surfaces prepared under optimal conditions. The results showed that the nano-/micro-structured etched aluminium surface with an optimal 0.5 M concentration of CuCl2 grafted with a perfluoroalkyl silane film achieved superhydrophobic characteristics, with water droplets exhibiting efficient corrosion protection, self-cleaning ability, and improved anti-icing performance with decreased ice nucleation temperature and up to 545% increased freezing delay.

We synthesized four new copper(II) complexes with acetato and chlorido ligands and methylammonium (MA), dimethylammonium (DMA), and tetramethylammonium (TMA) counterions: (MA)4[Cu2Ac4Cl2]Cl2·2H2O (1), (DMA)2[Cu2Ac4Cl2] (2), (DMA)4[Cu2Ac4Cl2]Cl2·2H2O (3), and (TMA)5[Cu2Ac4Cl]Cl4·4H2O (4). All compounds were characterized by single-crystal X-ray diffraction, magnetic measurements, FTIR spectroscopy, and thermogravimetric analysis. Complexes 1, 2, and 3 consist of a dinuclear coordination anion [Cu2(Ac)4Cl2]2− with bridging acetato ligands arranged in a paddle-wheel conformation and square-pyramidal coordination around Cu(II) atoms, while the coordination anion in compound 4 is a polymeric chain, parallel to the c axis, with Cu2(Ac)4 units connected through bridging chlorido ligands. Magnetic measurements carried out between 2 K and 300 K indicate strong antiferromagnetic interactions between Cu(II) ions. The effective magnetic moments range from 1.94 μB to 2.21 μB, exceeding the spin-only value for Cu(II) ions (μeff=1.73 μB) and suggesting significant orbital contributions to the magnetic moment. Thermogravimetric analysis of all complexes showed a multistep decomposition behavior yielding elemental copper as the final product.

Background: Slovenian children are facing considerable health challenges from the rapid social changes that influence their opportunity to engage in daily physical activity. Objective: To overlay the social changes to the established Report Card model as a means of contextualising the extreme changes in physical activity and fitness observed over several years. Methods: Benchmarks were graded for 10 core indicators, plus two (Sleep, Seasonal Variations). Active Healthy Kids Slovenia members met (predominantly via zoom) liaising with team leader(s) on a flexible, individual basis, based on coronavirus disease 2019 (COVID-19) regulations, over the ∼2-year assessment period of the project. Data were separated to the years prior to, ‘pre’ 2018–2020, and ‘during’ the global pandemic (2020–2021). Where sufficient data existed for both timeframes, grades were averaged to produce an overall grade. Results: Grade results are expressed as pre/during/final grade, where the final grade (bolded) is a straight average of the two preceding time epochs: Overall Physical Activity (A-/A-/A-), Organized Sport and Physical Activity (C+/C/C), Active Play (D/C+/C), Active Transport (C/INC/C), Sedentary Behaviour (B/C/C+), Physical Fitness (A+/A-/A), Family and Peers (B+/INC/B+), Schools (A/A/A), Community and Environment (A+/A+/A+), Government (A/F/D), Sleep (D-/INC/D-), Seasonal Variations (D/C-/D+). Conclusion: Although Slovenia has some of the most consistently physically-active children in the world, the effects of the COVID-19 pandemic exerted significant reductions in physical activity opportunities, and especially when coupled with funding re-distributions, resulted in the steepest decline of child physical fitness observed within the >35-year history of Slovenia's well-established national fitness surveillance system.

The rapid progress of electronic devices has necessitated efficient heat dissipation within boiling cooling systems, underscoring the need for improvements in boiling heat transfer coefficient (HTC) and critical heat flux (CHF). While different approaches for micropillar fabrication on copper or silicon substrates have been developed and have shown significant boiling performance improvements, such enhancement approaches on aluminum surfaces are not broadly investigated, despite their industrial applicability. This study introduces a scalable approach to engineering hierarchical micro-nano structures on aluminum surfaces, aiming to simultaneously increase HTC and CHF. One set of samples was produced using a combination of nanosecond laser texturing and chemical etching in hydrochloric acid, while another set underwent an additional laser texturing step. Three distinct micropillar patterns were tested under saturated pool boiling conditions using water at atmospheric pressure. Our findings reveal that microcavities created atop pillars successfully facilitate nucleation and micropillars representing nucleation site areas on a microscale, leading to an enhanced HTC up to 242 kW m−2 K−1. At the same time, the combination of the surrounding hydrophilic porous area enables increased wicking and pillar patterning, defining the vapor–liquid pathways on a macroscale, which leads to an increase in CHF of up to 2609 kW m−2.

The study aimed to develop a superhydrophobic coating on the aluminium alloy 2024-T3 surface. The desired surface roughness and low surface energy were achieved with SiO2 nanoparticles, synthesised via the Stöber method and modified with alkyl silane (AS) or perfluoroalkyl silane (FAS). To enhance particle adhesion to the alloy substrate, nanoparticles were incorporated into a hybrid sol–gel coating composed of tetraethyl orthosilicate, methyl methacrylate, and 3-methacryloxypropyl trimethoxysilane. The coated substrates were characterised using field emission scanning and transmission electron microscopy with energy-dispersive spectroscopy for surface topography, nanoparticle size distribution, composition, and coating thickness. The corrosion resistance of the coatings on AA2024-T3 was evaluated in a 0.1 M NaCl solution using electrochemical impedance spectroscopy. The synthesised SiO2 nanoparticles had an average size between 25 and 35 nm. The water contact angles on coated aluminium surfaces reached 135° for SiO2 + AS and 151° for SiO2 + FAS. SiO2 + FAS, indicating superhydrophobic properties, showed the most uniform surface with the most consistent size distribution of the SiO2 nanoparticles. Incorporation of nanoparticles into the hybrid sol–gel coating further improved particle adhesion. The ~2 µm-thick coating also demonstrated efficient barrier properties, significantly enhancing corrosion resistance for over two months under the test conditions. [ABSTRACT FROM AUTHOR]

This study establishes the subsolidus phase relations in the Bi₂O₃–Mn₂O₃–M₂O₃ (M = Fe, Al, and Ga) systems at 770°C in an oxidizing air environment, with a specific focus on identifying of phase stability and extension of solid solubility of new solid solutions. The pseudoternary nature of these systems is influenced by the presence of both Mn3⁺ and Mn⁴⁺ oxidation states in mullite Bi2Mn4O10‐based phases and Mn4+ in sillenite Bi12MnO20‐based phases. Our findings reveal that the addition of M₂O₃ (where M = Fe, Al, and Ga) in small amounts (up to 1.5 mol%) to Bi₂O₃ promotes the formation of the γ‐Bi₂O₃ phase. However, with increased M₂O₃ addition (up to 7 mol%), isomorphous sillenite compounds Bi₂₅MO₃₉ are formed. These findings clearly show differences between the two phases, γ‐Bi2O3 and sillenite Bi₂₅MO₃₉ which have been largely incorrectly defined in the past. In contrast, in the binary system Bi2O3–Mn2O3 the γ‐Bi2O3 was not identified. The sillenite compounds Bi12MnO20 and Bi25MO39 exhibit solid solubility in all three systems M = Fe, Al, and Ga over the entire composition range. Additionally, the perovskite phase BiFeO₃ exhibits an extended solid solubility, incorporating up to 32 at% of Mn as a substitution for Fe however the perovskite‐type BiGaO3 and BiAlO3 were not confirmed in the investigated systems. In the investigated systems, the mullite‐type Bi2Mn4O10 and Bi2M4O9 (M = Fe, Al, and Ga) form solid solutions with various compositional extensions, which depends on the difference of ionic size of M atoms (Fe, Al, and Ga) in comparison of Mn size. Based on experimental results, the three phase diagrams of the Bi₂O₃–Mn₂O₃–M₂O₃ (M = Fe, Al, and Ga) systems were constructed. [ABSTRACT FROM AUTHOR]

Increasing energy demand and limited non-renewable energy resources have raised energy security concerns within the European Union. With the EU's commitment to becoming the first climate-neutral continent, transitioning to renewable energy sources has become essential. While wind and solar energy are intermittent, consistent and reliable green energy sources, such as biogas and biomethane, offer promising alternatives. Biogas and biomethane production from biomass address key challenges, including grid stability ("supply on demand"), decentralized energy production, energy density, and efficient storage and transportation via existing natural gas infrastructure. This study examines technologies for converting woody biomass into biomethane and proposes a conceptual design utilizing the best available technologies. The system, situated in Slovenia's Kočevje region—one of Europe's richest forest habitats—was scaled based on the availability of low-quality woody biomass unsuitable for other applications. Combining biomass gasification, catalytic methanation, and biomethanation, supplemented by hydrogen from electrolysis, provides an effective method for converting wood to biomethane. Despite the system's complexity and current technological limitations in energy efficiency, the findings highlight biomethane's potential as a reliable energy carrier for domestic and industrial applications. [ABSTRACT FROM AUTHOR]

Prior studies have evidenced the potential for enhancing boiling heat transfer through modifications of surface or fluid properties. The deployment of nanofluids in pool boiling systems is challenging due to the deposition of nanoparticles on structured surfaces, which may result in performance deterioration. This study addresses the use of TiO2–water nanofluids (mass concentrations of 0.001 wt.% and 0.1 wt.%) in pool boiling heat transfer and concurrent mitigation of nanoparticle deposition on superhydrophobic laser-textured copper surfaces. Samples, modified through nanosecond laser texturing, were subjected to boiling in an as-prepared superhydrophilic (SHPI) state and in a superhydrophobic state (SHPO) following hydrophobization with a self-assembled monolayer of fluorinated silane. The boiling performance assessment involved five consecutive boiling curve runs under saturated conditions at atmospheric pressure. Results on superhydrophilic surfaces reveal that the use of nanofluids always led to a deterioration of the heat transfer coefficient (up to 90%) compared to pure water due to high nanoparticle deposition. The latter was largely mitigated on superhydrophobic surfaces, yet their performance was still inferior to that of the same surface in water. On the other hand, CHF values of 1209 kW m−2 and 1462 kW m−2 were recorded at 0.1 wt.% concentration on both superhydrophobic and superhydrophilic surfaces, respectively, representing a slight enhancement of 16% and 27% compared to the results obtained on their counterparts investigated in water.

Atopic dermatitis (AD) is the most common chronic inflammatory skin disease of childhood. The disease is characterized by recurrent eczematoid itchy skin lesions caused by a combination of genetic predisposition and environmental factors (1-2). The disease usually appears in the first year of life and its course is generally mild, although occasionally, due to the intensity of the disease, treatment with systemic immunosuppressive drugs is required. (1-3, 7). In this paper, we present the case of an 8 - year - old boy with severe atopic dermatitis that could not be controlled with local therapy. With cyclosporin treatment at the desired therapeutic level of the drug, the disease subsided, and the number of bacterial superinfections and herpes simplex virus infections decreased. With long-term treatment, good attenuation of skin inflammation was achieved and cyclosporin treatment was successfully discontinued.

Vacuum freeze-drying as a process for achieving high product quality has attracted increasing attention in the last decade. Particularly in the pharmaceutical field and food processing industries, lyophilization can produce high-quality products compared to samples dried by conventional methods. Despite its benefits, lyophilization is a time-consuming and costly process that requires optimization of a number of process parameters, including shelf temperature, chamber pressure, freezing rate, and process time. This paper reports on the implementation of heat flux measurements that allow noninvasive real-time determination of the endpoint of the primary drying stage as an essential parameter for the effective optimization of the overall drying time. Quantitative analysis of the drying kinetics of five fruits (kiwifruit, avocado, Asian pear, persimmon, and passion fruit) was assessed by comparing the heat flux and temperature profiles of samples during the lyophilization process. For a 24 h lyophilization cycle, average heat fluxes in the primary drying phase ranged from 250 to 570 W/m2. A significant correlation was found between the temperature and heat flux distributions at the estimated endpoint of the sublimation process and the corresponding transition into the secondary drying stage. Furthermore, good agreement was also found for the freezing phase. The use of real-time heat flux measurements proved to be a cost-effective experimental method to better understand the process variables in order to reduce the lyophilization cycle time and overall energy consumption.

This study aimed to prepare a facile hierarchical aluminium surface using a two-step process consisting of chemical etching in selected concentrations of CuCl2 solution and surface grafting through immersion in an ethanol solution containing 1H, 1H, 2H, 2H-perfluorodecyltriethoxysilane. The goal was to achieve superhydrophobic characteristics on the aluminium surface, including enhanced corrosion resistance, efficient self-cleaning ability, and improved anti-icing performance. The surface characterisation of the untreated aluminium and treated in CuCl2 solutions of different concentrations was performed using contact profilometry, optical tensiometry, and scanning electron microscopy coupled with energy dispersive spectroscopy to determine the surface topography, wettability, morphology, and surface composition. The corrosion properties were evaluated using potentiodynamic measurements in simulated acid rain solution and salt-spray test according to ASTM B117-22. In addition, self-cleaning and anti-icing tests were performed on superhydrophobic surfaces prepared under optimal conditions. The results showed that the nano-/micro-structured etched aluminium surface with an optimal 0.5 M concentration of CuCl2 grafted with a perfluoroalkyl silane film achieved superhydrophobic characteristics, with water droplets exhibiting efficient corrosion protection, self-cleaning ability, and improved anti-icing performance with decreased ice nucleation temperature and up to 545% increased freezing delay. [ABSTRACT FROM AUTHOR]

We synthesized four new copper(II) complexes with acetato and chlorido ligands and methylammonium (MA), dimethylammonium (DMA), and tetramethylammonium (TMA) counterions: (MA)4[Cu2Ac4Cl2]Cl2·2H2O (1), (DMA)2[Cu2Ac4Cl2] (2), (DMA)4[Cu2Ac4Cl2]Cl2·2H2O (3), and (TMA)5[Cu2Ac4Cl]Cl4·4H2O (4). All compounds were characterized by single-crystal X-ray diffraction, magnetic measurements, FTIR spectroscopy, and thermogravimetric analysis. Complexes 1, 2, and 3 consist of a dinuclear coordination anion [Cu2(Ac)4Cl2]2− with bridging acetato ligands arranged in a paddle-wheel conformation and square-pyramidal coordination around Cu(II) atoms, while the coordination anion in compound 4 is a polymeric chain, parallel to the c axis, with Cu2(Ac)4 units connected through bridging chlorido ligands. Magnetic measurements carried out between 2 K and 300 K indicate strong antiferromagnetic interactions between Cu(II) ions. The effective magnetic moments range from 1.94   μ B to 2.21   μ B , exceeding the spin-only value for Cu(II) ions ( μ e f f = 1.73   μ B ) and suggesting significant orbital contributions to the magnetic moment. Thermogravimetric analysis of all complexes showed a multistep decomposition behavior yielding elemental copper as the final product. [ABSTRACT FROM AUTHOR]

Droplet impacting and freezing on solid surfaces are ubiquitous in nature and crucial to many industrial applications, while the underlying mechanism of this phenomenon remains elusive. In this paper, the effect of surface wettability on dynamic behaviors and freezing mechanism of a water droplet impacting on a solid substrate at a fixed Weber number of 200 has been experimentally investigated at various surface temperatures from −35.2 to −10 °C. With the decrease in temperature of the superhydrophobic surface, the complete rebound behavior moves to partial rebound and ultimately to full adhesion, mainly due to the competition between the fluid dynamics and heat transfer processes. An intense prompt splashing is achieved by altering the surface wettability toward superhydrophobicity. Raising the water repellency enhances the lift of the lamella rim during the initial droplet spreading. The receding velocity on superhydrophobic surfaces is about ten times larger than that on hydrophobic surfaces, while it is barely affected by the surface and droplet temperatures. Three distinct freezing shapes are observed in the experiments, namely, spherical ice, irregular ice, and central cap ice, and those can be explained through the analysis of the differences between the time for the onset of freezing and receding time. Some cases of droplet freezing after full receding, also known as spherical ice, include two freezing stages. First, the liquid–gas interface freezes within a short period. Next, the remaining liquid freezes upward because the evaporation through the liquid–gas interface leads to the temperature of this interface being lower than the liquid–surface interface temperature. A phase diagram described by the final equilibrium contact factor and the surface temperature reveals the conditions to form different freezing processes or to remain a liquid state. [ABSTRACT FROM AUTHOR]

Heat transfer coefficients and nucleation parameters were experimentally measured during saturated nucleate boiling of water–glycerin mixtures on a thin smooth titanium foil. Infrared thermometry was employed to study boiling of water–glycerin mixtures at atmospheric pressure in water mass fraction range from 100 % down to 60 % and heat flux range from 0 to 200 kW m−2. Heat transfer coefficients were found to deteriorate with an increase of concentration of glycerin in the boiling mixture. The deterioration was more pronounced for mixtures with lower water mass fraction and for higher heat fluxes. Bubble departure diameters were observed to be weakly dependent on heat flux and independent of composition of the boiling mixture. Nucleation frequencies were found to increase with heat flux and to be inversely proportional to water mass fraction of the boiling mixture. Thermal energy transferred during nucleation of individual bubbles was independent of both heat flux and mixture composition. Values and trends of evaluated parameters suggest that for investigated mixtures and boiling conditions, heat transfer into the liquid phase is more important relative to the transport of latent heat by nucleating bubbles.