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The aim of this study was to evaluate the impact of sumac on the oxidation status, sensory properties, and physicochemical and microbiological parameters of common carp (Cyprinus carpio) fish during chilled storage. Fillets of carp were treated with ground sumac at percentages of 0% (T0), 0.5% (T1), 1.5% (T2) and 2.5% (T3) and analysed after 24 and 72 h of chilled storage. The fat content, oxidation parameters (thiobarbituric acid reactive substances, TBARS), antioxidant capacity, total volatile basic nitrogen (TVB-N), free fatty acids (FFA), sensory properties, colour indicators (lightness L*, redness a*, yellowness b*), water activity, pH value, aerobic plate count (APC), psychrotrophic microorganism count (PMC), and coliform bacteria count were determined. The TBARS values of T1, T2, and T3 decreased significantly (p < 0.05) after 24 h of chilled storage. The antioxidant capacity increased in a dose-dependent and time-dependent manner. As regards organoleptic properties, sumac was able to reduce the natural fishy odour, increase the sour odour and flavour, and mask the fish odour and flavour significantly. A significant effect of sumac on the redness (a*) values of muscles was observed, which increased with elevation of the sumac ratio. A decrease in fillet pH and lower APC and PMC were observed. No effect was found on water activity or the growth of coliform bacteria. The study found that sumac plays a role in the oxidation status, pH value and organoleptic properties of fish fillets, which could be beneficial for the fish and fishery products industry.

This study investigates the pH values and optical characteristics of Dual Rinse HEDP, either independently or combined with sodium hypochlorite (NaOCl), and compares them to other irrigants used in endodontics. The solutions used in this study were commercially acquired and prepared, followed by pH measurements using a pH meter and spectral analysis using UV/Vis spectrophotometry in specified wavelengths of the ultraviolet (UV) C (190–280 nm), UVB (281–315 nm), UVA (316–400 nm), visible light (VL) (401–780 nm), and near-infrared (NIR) spectra (781–1100 nm). The pH analysis revealed alkaline values for NaOCl, EDTA, Dual Rinse HEDP, and the HEDP + NaOCl combination, an acidic value for citric acid, and nearly neutral values for chlorhexidine and distilled water. Spectral analysis revealed the notable absorption characteristics of endodontic irrigants. In the UV range, all solutions exhibited higher absorption values to water (p < 0.05), with Dual Rinse HEDP resembling EDTA and citric acid, and HEDP + NaOCl resembling NaOCl. The NIR region highlights absorption peaks around 975 nm for all solutions, including NaOCl and Dual Rinse HEDP + NaOCl, suggesting potential applications in laser-activated irrigation. This study provides comprehensive insights into the pH and optical features of endodontic irrigants, emphasizing their potential roles in enhancing disinfection strategies and optimizing laser-activated irrigation protocols.

In this study, the effects of pH and NaCl concentrations on the structure of golden pompano myosin and emulsion gel were analyzed using SEM in combination with molecular dynamics simulations (MDS). The microscopic morphology and spatial structure of myosin were investigated at different pH (3.0, 7.0, and 11.0) and NaCl concentrations (0.0, 0.2, 0.6, and 1.0 M), and their effects on the stability of emulsion gels were discussed. Our results show that pH had a greater effect on the microscopic morphology of myosin than NaCl. The MDS results show that under the condition of pH 7.0 and 0.6 M NaCl, the myosin expanded and experienced significant fluctuations in its amino acid residues. However, NaCl showed a greater effect on the number of hydrogen bonds than pH. Although changes in pH and NaCl concentrations only slightly altered the secondary structures in myosin, they, nevertheless, significantly influenced the protein spatial conformation. The stability of the emulsion gel was affected by pH changes but not NaCl concentrations, which only affect the rheology. The best elastic modulus G″ of the emulsion gel was obtained at pH 7.0 and 0.6 M NaCl. Based on the results, we conclude that pH changes have a greater influence than NaCl concentrations on the spatial structure and conformation of myosin, contributing to the instability of its emulsion gel state. The data from this study would serve as a valuable reference for emulsion gel rheology modification in future research.

To disclose influences of ultrasonic vibration agitation on the carbonation resistance of cement-based materials after absorption of CO2, the variation laws in internal carbonization zone were explored by the testing carbonization depth and carbonization range (pH variation range) of cement mortar after CO2 absorption at different ages. Results demonstrated that when CO2 absorption volumes of the cement mortar before carbonization were 0.44%, 0.88%, 1.32%, 1.76%, and 2.20% (28 d), the carbonization depth under ultrasonic vibration decreased by 5.5%, 12.3%, 21.7%, 20.7%, and 26.7% compared to those under mechanical stirring, respectively. When the ultimate CO2 absorption volume increased to 2.2% of cement mass, the extended degree of cement mortar was 103.23 mm, which decreased by 5.4% compared to that before CO2 absorption. pH variation values of the carbonization range under ultrasonic vibration presented a rising trend with the increase of CO2 absorption volume of cement mortar before carbonation. This indicated that, with the increase of CO2 absorption volume of cement mortar before carbonation increases under ultrasonic vibration, the carbonization process of the hardened body of cement mortar might be decelerated to some extent. Additionally, changes in internal composition and physical images of cement-based materials after absorption of CO2 were analyzed through microtest means like SEM and XRD. A carbonation resistance model was constructed, thus enabling disclosure of the variation mechanism of carbonation resistance of cement-based materials after absorption of CO2 under mechanical stirring and ultrasonic vibration. Results demonstrated that the higher CO2 absorption volume of fresh slurry generated more “nano-level” CaCO3 crystal nucleus. Accordingly, it could improve the porous structure of the cement mortar, decrease the quantity of capillary tubes significantly, improve the compaction degree of cement-based materials effectively, and lower the diffusion rate of CO2 in the cement paste base, thus improving the carbonation resistance. Research conclusions have important significance to decrease CO2 emissions and improve carbonation resistance of concrete.

La-doped α-Fe2O3 nanoparticles were synthesized by a hydrothermal method. The effects of pH value on the morphology, structure, and electrochemical stability of the La-doped α-Fe2O3 nanoparticles were investigated by X-ray diffraction, transmission electron microscopy, Fourier-transform infrared spectrum, and electrochemical methods. The results show that the La-doped α-Fe2O3 nanoparticles exhibit a uniform spherical morphology at pH = 6, and are agglomerated with a poor dispersion at pH = 4 and 8. The iron oxide lattice is distorted by the La-doping, which increases the Fe–O bond strength. The decreased Fe–O bond length and the increased Fe–O bond energy at pH = 6 improve the electrochemical stability of α-Fe2O3. The waterborne coating modified with La-doped α-Fe2O3 nanoparticles exhibits a steady corrosion resistance.