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The main purpose of these studies was to obtain carbon–carbon composites with a core built of carbon fibers and a matrix in the form of pyrolytic carbon (PyC), obtained by using the chemical vapor deposition (CVD) method with direct electrical heating of a bundle of carbon fibers as a potential electrode material for nerve tissue stimulation. The methods used for the synthesis of PyC proposed in this paper allow us, with the appropriate selection of parameters, to obtain reproducible composites in the form of rods with diameters of about 300 µm in 120 s (CF_PyC_120). To evaluate the materials, various methods such as scanning electron microscopy (SEM), scanning transmission electron microscope (STEM), high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and tensiometer techniques were used to study their microstructural, structural, chemical composition, surface morphology, and surface wettability. Assessing their applicability for contact with nervous tissue cells, the evaluation of cytotoxicity and biocompatibility using the SH-SY5Y human neuroblastoma cell line was performed. Viability and cytotoxicity tests (WST-1 and LDH release) along with cell morphology examination demonstrated that the CF_PyC_120 composites showed high biocompatibility compared to the reference sample (Pt wire), and the best adhesion of cells to the surface among all tested materials.

In this paper, raw glazes from the SiO2–Al2O3–CaO–MgO–K2O–Na2O system were examined. Zirconium oxide, in five different amounts – 1.5, 3, 6, 12 and 24 wt%, was added to the chosen system and heat treated at 1230 °C, where they were kept for an hour. The addition of zirconium oxide, especially in greater amounts, caused the crystalline phase of zirconium silicate and intact ZrO2 grains to appear. The amounts of these crystalline phases indicate that zirconium cations are present in the amorphous phase. Analysis of structural measurements showed that zirconium ions (Zr4+) have a depolymerizing effect on the glassy matrix of the glazes; however, it does not change subnets of an aluminum-silicon subnetwork. This is a new perspective on the matter, because it confirms that the addition of zirconium oxide causes those ions to be present not only in crystalline phases, but also some Zr4+ cations are located in the aluminosilicate subnetwork (Si–O–Si(Al)), in interstitial spaces, and it interacts only with silicon-oxygen bonds. Measurements of the color in the CIE L*a*b* system of the obtained glazes confirmed that the addition of zirconium oxide results in glaze with significantly higher whiteness (L* parameter increases) and a more monochromatic color (a* and b* parameters tend toward zero). The results of the surface smoothness were also presented, which clearly confirm that the higher content of zirconium crystalline phases results in obtaining a surface with higher roughness.

Organic solar cells are a promising candidate for practical use because of their low material cost and simple production procedures. The challenge is selecting materials with the right properties and how they interrelate in the context of manufacturing the device. This paper presents studies on CdSe/ZnS nanodots as dopants in a polymer–fullerene matrix for application in organic solar cells. An assembly of poly(3-hexylthiophene-2,5-diyl) and 6,6-phenyl-C71-butyric acid methyl ester was used as the active reference layer. Absorption and luminescence spectra as well as the dispersion relations of refractive indices and extinction coefficient were investigated. The morphologies of the thin films were studied with atomic force microscopy. The chemical boundaries of the ternary layers were determined by Raman spectroscopy. Based on UPS studies, the energy diagram of the potential devices was determined. The resistivity of the layers was determined using impedance spectroscopy. Simulations (General-Purpose Photovoltaic Device Model) showed a performance improvement in the cells with quantum dots of 0.36–1.45% compared to those without quantum dots.

The synthesis and characterization of iron oxide nanostructures, specifically snowflake architecture, are investigated for their potential applications in electrochemical sensing systems. A Raman spectroscopy analysis reveals phase diversity in the synthesized powders. The pH of the synthesis affects the formation of the hematite (α-Fe2O3) and goethite (α-FeOOH). Scanning electron microscopy (SEM) images confirm the distinct morphologies of the particles, which are selectively obtained through recrystallization during the elongated reaction time. An electrochemical analysis demonstrates the differing behaviors of the particles, with synthesis pH affecting the electrochemical activity and surface area differently for each shape. Cyclic voltammetry measurements reveal reversible dopamine detection processes, with snowflake iron oxide showing lower detection limits than a mixture of snowflakes and cube-like particles. This research contributes to understanding the relationship between iron oxide nanomaterials’ structural, morphological, and electrochemical properties. It offers practical insights into their potential applications in sensor technology, particularly dopamine detection, with implications for biomedical and environmental monitoring.

In this study, a sonochemical route for the preparation of a new Hf-MIL-140A metal–organic framework from a mixture of UiO-66/MIL-140A is presented. The sonochemical synthesis route not only allows the phase-pure MIL-140A structure to be obtained but also induces structural defects in the MIL-140A structure. The synergic effect between the sonochemical irradiation and the presence of a highly acidic environment results in the generation of slit-like defects in the crystal structure, which increases specific surface area and pore volume. The BET-specific surface area in the case of sonochemically derived Zr-MIL-140A reaches 653.3 m2/g, which is 1.5 times higher than that obtained during conventional synthesis. The developed Hf-MIL-140A structure is isostructural to Zr-MIL-140A, which was confirmed by synchrotron X-ray powder diffraction (SR-XRD) and by continuous rotation electron diffraction (cRED) analysis. The obtained MOF materials have high thermal and chemical stability, which makes them promising candidates for applications such as gas adsorption, radioactive waste removal, catalysis, and drug delivery.

Compounds of the silsesquioxane type are attractive material precursors. High molecular weights and well-defined structures predestine them to create ceramics with a controlled composition at the molecular level. New molecular precursors of ceramic materials with the ratio of Si:Ge = 7:1 atoms were obtained. The influence of organic substituents on the thermal decomposition processes of germasilsesquioxanes was investigated. Some of the structures obtained are characterized by a high non-volatile residue after the thermal decomposition process. The introduction of the germanium atom to the structure of the silsesquioxane molecular cage reduces the thermal stability of the obtained structures.

Glasses and devitrificates from the SiO2–B2O3–P2O5–K2O–CaO–MgO system with constant contents of SiO2 and P2O5 network formers, modified by the addition of B2O3, were analyzed. All materials were synthesized by the traditional melt-quenching technique. The glass stability (GS) parameters (Krg, ∆T, KW, KH) were determined. The effect of the addition of B2O3 on the GS, liquation phenomenon, crystallization process, and the type of crystallizing phases were examined using SEM-EDS, DSC, XRD, and Raman spectroscopy imaging methods. It was observed that the addition of B2O3 increased the tendency of the glass to crystallize. Both phosphates (e.g., Ca9MgK(PO4)7, Mg3Ca3(PO4)4), and silicates (e.g., K2Mg5(Si12O30), CaMg(Si2O6), MgSiO3) crystallized in the studied system. The Raman spectrum for the orthophosphate Mg3Ca3(PO4)4 stanfieldite type was obtained. Boron ions were introduced into the structures of crystalline compounds at high crystallization temperatures. The type of crystallizing phases was found to be related to the phenomenon of liquation, and the order of their occurrence was dependent on the Gibbs free enthalpy.

Abstract One of the most important field of interest in respect to hydrogel materials is their capability to water storage. The problem mentioned above plays an important role regarding to diffusion of fluid media containing nanoparticles, what is very useful in biomedical applications, such as artificial polymeric implants, drug delivery systems or tissue engineering. In presented work, dehydration process in hydrogels used in ophthalmology as intraocular lenses was observed. Before measurements studied materials were immersed in deionized water and saline solution to obtain equilibrium swelling state. Studies of the dehydration process were carried out by use of gravimetric analysis, Fourier-Transform Infrared and Positron Annihilation Lifetime Spectroscopy. Obtained results revealed changes in hydrogen bonding structure and free volume holes induced by saline solution ingredients.

W artykule zaprezentowano przegląd piśmiennictwa dotyczącego zastosowania treningu siłowego kończyn dolnych w rehabilitacji dorosłych pacjentów z mózgowym porażeniem dziecięcym. W tym celu przeszukano medyczne bazy danych przy użyciu słowa kluczowego „mózgowe porażenie dziecięce” w połączeniu ze słowami „dorośli”/„osoby dorosłe”, „młodzi dorośli”, „trening siłowy”, „progresywny trening siłowy” i „trening oporowy”. Zidentyfikowano dziewięć publikacji, do analizy wybrano zaś siedem badań spełniających kryteria włączenia. Poziom dowodu naukowego zaakceptowanych badań oceniono z wykorzystaniem kryteriów zaproponowanych przez Oxford Centre for Evidence-Based Medicine. Wyniki przedstawiono zgodnie z Międzynarodową Klasyfikacją Funkcjonowania, Niepełnosprawności i Zdrowia na trzech poziomach – struktury, aktywności i partycypacji – w formie tabelarycznej. Biorąc pod uwagę wyniki badań innych niż randomizowane, można stwierdzić, że trening siłowy u dorosłych z mózgowym porażeniem dziecięcym prowadzi do wzrostu siły mięśniowej oraz wpływa na poprawę aktywności, mobilności i uczestnictwa w życiu społecznym. Powyższe rezultaty nie zostały jednak do tej pory wystarczająco potwierdzone w pracach randomizowanych. Należy podkreślić, że zastosowane protokoły treningu siłowego nie wywołały negatywnych efektów na poziomie spastyczności i biernego zakresu ruchu. Maksymalizacja korzyści płynących z treningu siłowego w grupie osób dorosłych z mózgowym porażeniem dziecięcym wymaga rozstrzygnięcia szeregu kwestii, dotyczących m.in. szczegółowej charakterystyki pacjentów, protokołu treningowego i potencjalnych czynników kontekstowych mogących wpływać na efektywność terapii tego rodzaju.