In this study, two kinds of submicron- and micron-sized Sr-Fe-O oxides with soft and hard magnetism were successfully synthesized via a polyol process followed by heat treatment processes. X-ray diffraction (XRD), scanning electron microscopy (SEM), and vibrating sample magnetometer (VSM) techniques have been employed to determine of the structures and properties of the as-prepared Sr-Fe-O oxide powders. Submicron- and micron-sized Sr-Fe-O oxides with soft magnetism synthesized and treated at low temperatures, exhibit high saturation magnetization ($M_{\mathrm{s}}$) but low coercivity ($H_{\mathrm{c}}$) and remanence ($M_{\mathrm{r}}$). An interesting magnetic phenomenon was investigated, confirming that the hard magnetic phase obtained at $650$ and $950\,^{\circ}\mathrm{C}$ corresponds to $\mathrm{SrFe}_{12}\mathrm{O}_{19}/\alpha$-$\mathrm{Fe}_{2}\mathrm{O}_{3}$ hybrid structure. It was found that a $\mathrm{SrFe}_{12}\mathrm{O}_{19}/\alpha$-$\mathrm{Fe}_{2}\mathrm{O}_{3}$ hybrid crystal structure, in which the $\alpha$-$\mathrm{Fe}_{2}\mathrm{O}_{3}$ phase exhibits stronger crystallinity than the $\mathrm{SrFe}_{12}\mathrm{O}_{19}$ phase, was characterized, demonstrating large and stable $H_{\mathrm{c}}$ and $M_{\mathrm{r}}$ but a relatively high $M_{\mathrm{s}}$.
This study focuses on the synthesis and characterization of zinc (Zn)-doped cuprous oxide nanoparticles, denoted as ZnxCu2O, prepared by a room-temperature co-precipitation method. The Zn doping content was varied from 0 to 30%. X-ray diffraction (XRD) confirmed that the nanoparticles predominantly exhibit the cubic Cu2O phase. With increasing Zn content, the crystallite size gradually decreased, consistent with changes in lattice parameters and microstrain. Raman and FTIR analyses verified successful Zn incorporation, revealing modifications in Cu-O vibrational modes and the emergence of Zn-O bonding features. FE-SEM observations showed reduced particle size and increased agglomeration at higher Zn doping levels, in agreement with XRD results. Optically, the band gap energy (Eg) increased at low Zn doping due to the Burstein–Moss effect, then decreased at higher doping levels because of secondary ZnO phase formation. Photocatalytic experiments demonstrated that the sample with an optimal Zn content of 10% (x = 0.1) exhibited superior degradation performance toward common organic pollutants, including Rhodamine B, ciprofloxacin, and sulfamethoxazole. These results highlight the strong potential of ZnxCu2O nanomaterials for wastewater treatment and environmental remediation.
G6PD deficiency, an enzymopathy associated with glucose-6-phosphate dehydrogenase (G6PD), is caused by genetic mutations that reduce the enzyme activity, resulting in hemolytic anemia. Biochemical studies have shown that G6PD deficiency in various variants is associated with reduced thermal stability, reduced catalytic activity, or both. In this study, we investigate the structural stability of the wild-type G6PD monomer at a physiological temperature using molecular dynamics simulations, in the absence and in the presence of its G6P and NADP+ ligands. We find that the G6P ligand has a low affinity for the G6PD monomer, which may result from fluctuations in the size of its binding pocket. This finding is consistent with and helps explain the catalytic inactivity of monomeric G6PD. Our analysis also shows that, with a statistically significant confidence, class I mutations occur preferentially at residues that are more flexible than randomly selected residues, whereas class II mutations tend to occur at residues that are less flexible than randomly selected ones. This result reflects the distinct structural roles of the G6PD mutation sites and further supports the relationship between enzyme activity and thermal stability.
The development of a regularized perturbation theory method for solving the Schrödinger equation of an exciton in a black phosphorus monolayer—a two-dimensional anisotropic material—yields a novel form of double integrals that is substantially more complex than that in previous studies on isotropic excitons. Direct computation of these integrals requires a significant amount of computational time and resources. In this study, we propose an analytical calculation scheme for these integrals based on the Newton binomial theorem, combined with Taylor expansion and a regularization method that utilizes a free parameter. This approach expresses the integrals as linear combinations of simpler single integrals, which can be evaluated through recurrence relations, making them suitable for numerical implementation. Moreover, a free parameter is introduced and optimized to enhance calculation speed. With this scheme, the evaluation speed of the integrals is improved dramatically—by several orders of magnitude—resulting in exciton energy-level calculations that are accelerated by up to five orders of magnitude. These findings present a new approach for the numerical treatment of complicated integrals, thereby enhancing computational efficiency in similar problems.
This study investigates defect states in p-silicon wafer using Deep Level Transient Spectroscopy method. Two-hole traps with activation energy of 0.32 and 0.58 eV were observed at temperatures of 212 and 252 K, respectively. These hole traps could be boron-related defects introduced during doping process. By using capacitance-voltage measurement, the doping concentration was estimated to be approximately 7$\times$10\textsuperscript{15} cm\textsuperscript{-3}, and the maximum defect density of about 4$\times$10\textsuperscript{14} cm\textsuperscript{-3}. The obtained results showed that the high defect states could be formed naturally during deposition progress. Understanding how defects interact within p-Si is essential for defect engineering in the future.
