The aim of this work was to investigate the hydrocracking of algae oil derived from Spirulina Platensis species catalyzed with bi-component nickel-zirconia catalysts supported onto different carriers (BEA, ZSM-5 and Al₂O₃) in an autoclave at 320 °C for 2 h with a hydrogen pressure of 75 bar. All catalysts were prepared using the wet co-impregnation method and were characterized by H₂-TPR, XRD, NH₃-TPD, BET and SEM-EDS. Before reactions, catalysts were calcined at 600 °C for 4 h in a muffle furnace, then reduced with 5%H₂-95%Ar reducing mixture at 500 °C, 600 °C or 700 °C for 2 h. The obtained products were analyzed and identified by HPLC and GC-MS techniques. In addition to the investigation of the support effect, the influence of the reduction temperature of catalytic systems on the catalytic activity and selectivity of the products was also examined. The activity results show that Ni-Zr systems supported on zeolites exhibited high conversion of algal oil. A gradual decrease in conversion was observed when increasing the reduction temperature of the catalyst (from 500 °C to 600 °C and 700 °C) for BEA zeolite catalysts. The reaction products contain hydrocarbons from C₇ to C₃₃ (for zeolite-supported catalysts) and C₃₆ (for systems on Al₂O₃). The identified hydrocarbons mainly belong to the gasoil fraction (C₁₄–C₂₂). In the research, the best catalyst for the algal oil hydrocracking reaction was found to be the 5%Ni-5%Zr/BEA system reduced at 600 °C, which exhibited the second highest algal oil conversion (94.0%). The differences in catalytic activity that occur are due to the differences in the specific surface area among the supports and to differences in the acidity of the catalyst surface depending on the reduction temperature.

Nowadays deodorants and antiperspirants play an important role in maintaining daily hygiene, exerting a substantial influence on both physical comfort and social functioning. Consequently, they can be regarded as a pivotal component of contemporary personal hygiene programs. The aim of this study was to undertake a comparative analysis of the elemental composition of diverse samples (72) of various roll-on deodorants and antiperspirants, sticks, and solid natural potassium–aluminium alums. These analyses were performed using ICP-OES and SEM-EDS techniques. The obtained results were then subjected to statistical and chemometric analysis. Studies demonstrated that Al and Zr were the most significant elements in the tested samples. Aluminium, a prevalent component in antiperspirants, was quantified in concentrations ranging from 0.9% to 4.4%, and in potassium–aluminium alums up to 4.7%. Aluminium and zirconium compounds were found to be the predominant elements in stick antiperspirants, with zirconium levels reaching up to 3%. The presence of lead was quantified in 35 of the 72 samples, with 19 samples exhibiting concentrations exceeding 1 mg/L. The highest lead level, reaching 15.90 mg/L, was found in potassium–aluminium alum. Furthermore, SEM-EDS analysis was conducted to verify the elemental composition, to provide data on additional ingredients, and to partially verify the information contained on the product labels.

Methacrylate-POSS (M-POSS) is a novel organic–inorganic additive shown to reinforce dental composites and reduce polymerization shrinkage. This study aimed to evaluate the influence of M-POSS addition (0.5, 2, 10, or 15 wt.%) on the mechanical properties of an experimental polymer matrix (bis-GMA/UDMA/TEGDMA/HEMA = 35/35/20/10 wt.%) and a dental resin composite (45 wt.% silanized silica as filler). Vickers hardness (HV), three-point bending strength (FS), diametral tensile strength (DTS), and shrinkage stress generated during polymerization were studied. The results show HV values between 16 and 18 compared to 15 ± 1 in the control group. Hardness in the control composite was 34 ± 4, and after modification, it showed similar or slightly lower values between 32 and 35. FS increased from 90 ± 4 MPa before modification to 100 ± 5 MPa for 2 wt.% M-POSS, and then decreased to 78 ± 5 MPa for materials containing 15 wt.% M-POSS. FS of composites were within the range of 61–77 MPa, with a similar tendency in variation to that of matrices. DTS values decreased after M-POSS addition, from 37 ± 4 MPa before modification to 31–33 MPa after modification. Flexural modulus decreases after modification, both for matrices and composites. The morphology of composites with >10 wt. % M-POSS showed visible surface irregularities. In conclusion, M-POSS affects matrix hardness, resulting in an increase in HV. The addition of M-POSS also increases FS values of the matrix, but only up to a certain concentration. However, the introduction of M-POSS does not significantly affect the HV or bending strength of the composites. Although DTS values decreased, this change was not statistically significant. Finally, contraction stress was significantly reduced for groups containing 2 wt.% and 10 wt.% M-POSS, representing an anticipated and promising improvement.

The main goal of this work was to determine the role of copper in bimetallic nickel–copper BEA zeolite catalysts prepared by sequential impregnation and co-impregnation, as well as defining the influence of the method of impregnation on the catalytic activity of the described catalysts. The all-prepared samples were tested in hydrocracking reactions with rapeseed oil as a feedstock. The physicochemical properties of the catalytic materials were determined using H₂-TPR, TPD-NH₃, XRD, BET, and SEM-EDS techniques. The reaction products were analyzed using chromatographic techniques (HPLC and GC-MS). The bimetallic systems obtained post-impregnation exhibited lower conversions of rapeseed oil than catalysts synthesized by co-impregnation. For all bimetallic catalysts, oil conversion was higher than for the monometallic copper BEA zeolite catalyst. This indicates that nickel is responsible for better oil conversion. The highest oil conversion (92.7%) was noted for the co-impregnated 5%Ni-5%Cu_BEA zeolite catalyst. For all tested catalysts, the highest selectivity was noted for the gasoil fraction. However, the presence of copper in bimetallic Cu-Ni_BEA zeolite catalysts led to increased selectivity towards gasoline and kerosene compared to the monometallic nickel BEA zeolite catalyst.

The use of resin-based composite imitating gum tissue enhances the aesthetics of fillings located below the physiological gum line. The shear bond strength (SBS) between the gum-imitating composite and the traditional composite with different surface preparation methods was examined. The aim of the study was to evaluate which base material—G-aenial Universal Injectable (GC, Japan, flow) or G-aenial A’CHORD (GC, Japan, paste)—performs better, as well as to determine the most effective preparation method among sandpaper (control), 36% orthophosphoric acid (H₃PO₄), sandblasting, and 9.5% hydrofluoric acid (HF). The tested gum-imitating material was Amaris Gingiva (VOCO, Germany). The connection between the composites was evaluated using a Z005 (Zwick-Roell) universal device. Surface tests were carried out using an SJ-410 (Mitutoyo) profilometer. Evaluation of the prepared surface structures was performed using scanning electron microscopy (HITACHI S-4700). Etching with HF significantly improved the shear bond strength between composites. Sandblasting also enhanced the adhesion results, but the H₃PO₄ group achieved comparable results to the control group. However, since HF is not recommended for intraoral use, sandblasting (30 μm aluminum oxide particles applied with three passes at constant speed under a pressure of 2 bar from 1.5 cm) appears to be the most suitable clinical alternative.

While resin-based dental composites (RBCs) are widely recognized as the golden standard in restorative dentistry, there is a need for improvement in their properties, including their potential biofunctional behavior. The aim of this study was to assess the impact of hydroxyapatite (HA) filler on the mechanical properties and provide preliminary evidence of biofunctional potential of prepared experimental RBCs. The effects of two forms of HA filler, mHA (2.5 μm) and nHA (<200 nm), in three concentrations (2.5, 5.0, and 7.5 wt.%) were tested in regard to hardness (HV), diametral tensile strength (DTS), flexural strength (TPB), flexural modulus, and calcium and phosphate ion release. Modification with HA improves the Vickers hardness and diametral tensile strength of RBCs, but has mixed effects on the flexural strength. The tested materials meet the minimum requirements for DTS and TPB for commercial composites, but their HV is closer to flowable materials. Calcium and phosphorus are detectable on the surface of HA-modified materials via SEM-EDS. There is also preliminary evidence of calcium and phosphate ion release in materials modified with HA, with the concentrations of 5 wt.% HA and above, providing the highest levels.