The Role of Oxygen Vacancies in Phase Transition and the Optical Absorption Properties within Nanocrystalline ZrO2.

Zirconia (ZrO2) nanoparticles were synthesized using a solvothermal method under varying synthesis conditions, namely acidic, neutral, and alkaline. X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM) were leveraged to investigate the phase evolution and topographical features in detail. The resulting crystal phase structures and grain sizes exhibited substantial variation based on these conditions. Notably, the acidic condition fostered a monoclinic phase in ZrO2, while the alkaline condition yielded a combination of tetragonal and monoclinic phases. In contrast, ZrO2 obtained under neutral conditions demonstrated a refinement in grain sizes, constrained within a 1 nm scale upon an 800 °C thermal treatment. This was accompanied by an important transformation from a monoclinic phase to tetragonal phase in the ZrO2. Furthermore, a rigorous examination of XPS data and a UV-visible spectrometer (UV-vis) analysis revealed the significant role of oxygen vacancies in phase stabilization. The notable emergence of new energy bands in ZrO2, in stark contrast to the intrinsic bands observed in a pure monoclinic sample, are attributed to these oxygen vacancies. This research offers valuable insights into the novel energy bands, phase stability, and optical absorption properties influenced by oxygen vacancies in ZrO2. Moreover, it proposes an innovative energy level model for zirconia, underpinning its applicability in diverse technological areas.

Mesoporous Poly(3,4-ethylenedioxythiophene):Poly(styrenesulfonate) as Efficient Iodine Host for High-Performance Zinc-Iodine Batteries.

Here, by introducing polystyrenesulfonate (PSS) as a multifunctional bridging molecule to synchronously coordinate the interaction between the precursor and the structure-directing agent, we developed a mesoporous conductive polymer of poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) featuring adjustable size in the range of 105-1836 nm, open nanochannels, large specific surface area (105.5 m2 g-1), and high electrical conductivity (172.9 S cm-1). Moreover, a large-area ultrathin PEDOT:PSS thin film with well-defined mesopores can also be obtained by controllable growth on various functional interfaces. As an example, we demonstrated that the iodine-loaded mesoporous PEDOT:PSS nanospheres can serve as a promising cathode for aqueous zinc-iodine batteries with high specific capacity (241 mAh g-1), excellent rate performance, and superlong 20,000 cycle life. In-depth theoretical calculations and systematic experimental results together reveal that the exposed sulfur- and oxygen-containing functional groups hold strong interactions with iodine species, resulting in effectively anchoring iodine species and inhibiting the shuttling of polyiodide intermediates, thus ensuring the long-term stability of the batteries. This work introduces a member to the family of mesoporous materials as well as porous polymers with versatile applications.

Enhanced flotation efficiency of metal from waste printed circuit boards modified by alkaline immersion.

Efficient recycling of waste printed circuit boards by flotation has become a research focus. In this study, waste printed circuit boards were treated by alkaline immersion to enhance the flotation efficiency. Firstly, the SEM-EDS analysis of the crushed products shown that metal and nonmetal were completely liberated in the -0.25 mm fraction. When the printed circuit boards were modified by alkaline immersion, the recovery of metal increased from 64.34% to 72.35%. Further, the mixture of metal and nonmetal at the edge of nonmetal was discovered by EPMA. This was the cause of metal loss during the flotation process. Secondly, by adjusting the alkaline immersion time and pH value, a good flotation effect was achieved at 40 min alkaline immersion time and the pH = 11. Meanwhile, the XPS analysis of nonmetal found that the intensity of the OH peak was significantly enhanced, while the intensity of the O peak was evidently decreased. The change of the resin molecular structure indicated that the O linked to the benzene ring was broken under the action of alkaline immersion, resulting a free bond was generated on the benzene ring. This made the free OH adsorb to the free bond. This conduct promoted the dispersion of nonmetal in the slurry due to the increased nonmetal surface energy and metal hydrophilicity. Thus, this study provides a new route to improve the flotation efficiency of waste printed circuit boards.

Effects of single-port laparoscopic percutaneous extraperitoneal closure on the orientation of the vas deferens and testicular perfusion and volume: Experience from a single center.

OBJECTIVE: To investigate the influence of single-port laparoscopic percutaneous extraperitoneal closure (LPEC) on the orientation of the vas deferens and testicular perfusion and volume in pediatric patients undergoing inguinal hernia repair. METHODS: A total of 92 consecutively enrolled boys preoperatively diagnosed with a unilateral inguinal hernia underwent single-port LPEC between June 2013 and June 2014. The orientation of the vas deferens and the testicular perfusion and volume of these patients were ultrasonographically assessed preoperatively, one month after surgery and six months after surgery. RESULTS: The surgical procedures were performed successfully without conversion or serious perioperative complications. Ultrasonography showed no angulation or distortion of the vas deferens on the surgical side during a six-month follow-up period. Similarly, there were no perioperative changes in testicular perfusion or volume. CONCLUSION: Our experience suggests that the single-port LPEC technique can be safe and effective in pediatric patients with an inguinal hernia and that this technique does not affect the orientation of the vas deferens or testicular perfusion or volume.

Application of a Laparoscopic, Single-port, Double-needle Technique for Pediatric Hydroceles With Multiple Peritoneal Folds: A Trial From a Single-center 5-Year Experience.

OBJECTIVE: To report our 5-year experience with a modified single-port, double-needle, minilaparoscopic technique for patent processus vaginalis with multiple peritoneal folds in the hydrocele sac orifice. METHODS: A total of 125 consecutive cases of boys with unilateral pediatric hydrocele underwent minilaparoscopic repair between June 2008 and June 2013. The patients were divided into 2 groups. Group 1 consisted of 65 patients who underwent a 2-port laparoscopic procedure, during which a 3-mm grasping forceps was used to grasp the folds around the internal inguinal ring. Group 2 included 60 patients who received a modified single-port, double-needle, minilaparoscopic surgery. An Endo Close needle was used to spread the peritoneal folds and facilitate circular extraperitoneal suturing in group 2. The principal outcome factors were assessed between the groups. RESULTS: A total of 151 minilaparoscopic procedures were performed in 125 patients (age range, 12-68 months; median, 21.5 months). In total, 26 extra procedures were performed for simultaneous repair of a potential contralateral patent processus vaginalis. No significant difference in operation time was noted between group 1 and group 2 (25.9 ± 6.4 vs 27.1 ± 5.5 minutes). The procedures were performed successfully without serious preoperative complications. During a median follow-up period of 18 months (range, 6-36 months), no postoperative hydrocele recurrence was encountered. CONCLUSION: Our limited experience suggests that the modified single-port, double-needle, minilaparoscopic technique could be safe, effective, and more cosmetically appealing for the management of complicated pediatric hydroceles.

Development of a conjugate vaccine against invasive pneumococcal disease based on capsular polysaccharides coupled with PspA/family 1 protein of Streptococcus pneumoniae.

The efforts were focused on exploring alternative pneumococcal vaccine strategies, aimed at addressing the shortcomings of existing formulations, without compromising efficacy. Our strategy involved the use of the carrier protein, pneumococcal surface protein A (PspA), conjugated with capsular polysaccharides (CPS), to provide effective and non-serotype-dependent protection. In this study, we generated a stable Escherichia coli construct expressing functional PspA from a capsular serotype 6B strain and confirmed it belonging to family 1, which was conjugated with CPS. The distribution of anti-CPS antibody response was almost completely of IgG2a subclass followed by IgG3 and low level of IgG1 subclass, but that of anti-PspA IgG subclass antibodies was almost equal IgG1 and IgG2a subclasses. Though PspA was less conspicuous on the surface of pneumococci than the capsule, the antibodies induced with CPS-rPspA conjugate possessed more accessibility to the surface of Streptococcus pneumoniae serotype 6B and 19F (the same family 1 PspA). By survival experiment, the result suggested that the level of cross-protection after immunized with the conjugate was more measurable within the same family 1. The CPS-rPspA conjugate not only induced CPS-specific protection but also provided PspA specific cross-protection.