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A *BEA-type titanosilicate, Ti-Beta, has been synthesized by a new method using mechanochemical reaction. In this new synthesis method, titania and silica powders are used as source materials and ground by using a planetary ball mill. Thus obtained silica–titania composite is hydrothermally treated in the presence of tetraethylammonium fluoride as a structure-directing agent to obtain a Ti-Beta material. The titanosilicate samples obtained are characterized by powder X-ray diffractometry and UV–visible spectroscopy. The crystallization behaviors and the catalytic activities of Ti-Beta materials synthesized by this new method are compared with those synthesized conventionally from silicon and titanium alkoxides.

MFI-type titanosilicate zeolite TS-1 is synthesized via a newly developed mechanochemical route, and the effects of mechanochemical reaction conditions on the physical and chemical properties are investigated. In the mechanochemical route, titania and silica powders are ground by using a planetary ball mill to yield a silica-titania composite powder, which is converted into TS-1 through hydrothermal treatment. TS-1 samples are characterized by powder X-ray diffractometry and UV-visible spectroscopy, and their catalytic activities in the alkene oxidation reaction are evaluated. Several parameters of the mechanochemical reaction such as the disk rotation speed, the grinding time, and the molar ratio of silica and titania are changed to evaluate their effects on the properties of resulting materials. It is demonstrated that these parameters have significant effects on the physical and chemical properties of the final product.

Purpose We sought to evaluate the effectiveness of pneumatic retinopexy as an alternative technique for retinal detachment repair in patients with retinal dialyses that were greater than three clock hours in size and located in the superior eight clock hours of the retina. Methods We reviewed four consecutive cases of retinal detachment secondary to large superior retinal dialyses, extending at least three clock hours, that were successfully treated with pneumatic retinopexy. Results Follow-up ranged from nine to 28 months. All patients had postoperative corrected visual acuity of 20/40 or better. Within two years, one patient was noted to have a new break in the inferior retina not contiguous with the original dialysis that was successfully repaired with laser photocoagulation. Conclusion Pneumatic retinopexy offers a less invasive alternative to scierai buckling surgery in certain cases of superior retinal dialyses.

An easy and highly reproducible synthesis method for titanosilicate zeolites has been developed, which can use bulk titania and silica as source materials. In this method, a uniform silica–titania ...

In this paper we investigate the local adsorption geometry of CoPc films adsorbed on a Ag(100) surface and its effect on the molecule-substrate interactions. Using high-resolution electron energy loss spectroscopy we demonstrate that the charge-transfer mechanism at the organic-metal interface depends on the structural properties of the CoPc film. We discuss these findings in terms of the molecular adsorption sites, as determined by X-ray photoelectron diffraction measurements and multiple scattering simulations. We show that the distance between the central Co atom and the topmost Ag layer is of the order of 0.3 nm. In addition, we demonstrate that the Co Pc molecules adsorb on different atomic sites depending on the superlattice symmetry, as varied by changing the coverage. This is further confirmed by low-energy electron diffraction and scanning tunneling microscopy measurements, emphasizing that, depending on the molecular superstructure adopted by the molecules, there are one or two molecules per unit cell.