Urchin-like hollow SiO2@γ-MnO2 microparticles for the rapid degradation of organic dyes.

In this paper, using hollow silica microspheres as carriers, we developed a facile one-pot method for the preparation of hollow SiO2@MnO2 composite microparticles. Under a certain proportion of hollow silica microspheres and manganese salt, a novel kind of hollow urchin-like SiO2@γ-MnO2 microparticles was obtained. The structure and morphology of the composite microparticles were characterized by XRD, SEM and TEM. On this basis, using rhodamine B and methyl orange as model molecules, the oxidative degradation ability of the hollow SiO2@γ-MnO2 microparticles for organic dyes in water was investigated through UV-vis analysis technology. The urchin-like SiO2@γ-MnO2 microparticles showed excellent performance for the rapid oxidative degradation of organic dyes under acidic conditions. This study indicated that γ-MnO2 loaded on hollow materials can be used as an efficient tool for treating organic dye wastewater, and shows broad application prospects for solving environmental problems in the related industry.

Enhanced Catalytic Activity of Magnetic Bimetallic Ag-Au Nanoparticles Mediated by Surface Plasmon Resonance.

We firstly discover the enhanced catalytic activity of magnetic noble metal nanoparticles mediated by surface plasmon resonance. Under light irradiation with certain wavelength, the catalytic performance of magnetic noble metal nanoparticles shows changes with different degrees and directions that are associated with the surface plasmon resonance (SPR) of the noble metal. Moreover, the coupling of silver and gold allows the catalytic performance of magnetic bimetallic Ag-Au nanoparticles to show more positive response to surface plasmon resonance. The magnetic bimetallic Ag-Au nanoparticles show excellent catalytic performance toward the reduction reaction of aromatic nitro group, and corresponding rate constant of the catalytic reduction reaction increases about three times with light irradiation.

[Expression of receptor activator of NF-κB ligand and osteoprotegerin in peri-implant tissues during unloading period].

OBJECTIVE: To observe the expression of receptor activator of NF-κB ligand (RANKL) and its decoy receptor osteoprotegerin (OPG) during unloading period of dental implants. METHODS: An animal model of dental implants was established in Beagle dogs. Bone remodeling was tested at 3, 7, 15, 30, 60 and 90 days after the placement of implants. RANKL and OPG mRNA expression were quantified by real-time PCR. Then mandibular bones were resected and some sections were observed. RESULTS: The most prominent period of bone remodeling occurred at 7 day after the placement of implants (OPG/RANKL mRNA, 2.15 ± 0.1). The expression of RANKL and OPG increased in a time-dependent manner in both soft and hard tissue. After 7 days they gradually decreased. CONCLUSIONS: Both OPG and RANKL were expressed in peri-implant tissues, and the changing tendency of RANKL and OPGmRNA was consistent with the change of bone remodeling. The active stage for bone remodelling in peri-implant tissues during unloading period is about 7 days after implantation.

[The application of guided bone regeneration technique in the restoration of maxillary lateral incisor with bone defect].

PURPOSE: To evaluate the clinical effectiveness and the satisfaction on aesthetic effectiveness of application of guided bone regeneration (GBR) technique in maxillary lateral incisor implant site. METHODS: Ninety patients were selected who only lost maxillary lateral incisor and placed with 101 implants(the implant systems were 3i, Osstem, ITI, Ankylos, BLB). The final restorations were porcelain-fused-to-metal crowns. Clinical and X-ray examinations were conducted and esthetic results were observed at 3, 6,12 months after dental implant prosthetics. RESULTS: The follow-up time was 12 months, all patients achieved successful implantation and good osseointegration around the implant. The esthetic results were perfect .Among the 90 cases, 90.7%, 92.8% and 95.5% of the patients were satisfied with the final outcomes 3,6,12 months after prosthetics. CONCLUSIONS: Good clinical effectiveness and satisfaction on aesthetic effectiveness can be obtained with GBR technique applied in maxillary lateral incisor implant site. Appropriate use of GBR technique is the solution of bone defect of maxillary lateral incisor implant site.