ABSTRACT
We report the design, fabrication and characterization of novel TiO2 nanotube photonic crystals with a crystalline core/disordered shell structure as well as substantial oxygen vacancies for photoelectrochemical (PEC) water splitting. The novel TiO2 nanotube photonic crystals are fabricated by annealing of anodized TiO2 nanotube photonic crystals in hydrogen atmosphere at various temperatures. The optimized novel TiO2 nanotube photonic crystals produce a maximal photocurrent density of 2.2 mA cm-2 at 0.22 V versus Ag/AgCl, which is two times higher that of the TiO2 nanotube photonic crystals annealed in air. Such significant PEC performance improvement can be ascribed to synergistic effects of the disordered surface layer and oxygen vacancies. The reduced band gap owing to the disordered surface layer and localized states induced by oxygen vacancies can enhance the efficient utilization of visible light. In addition, the disordered surface layer and substantial oxygen vacancies can promote the efficiency for separation and transport of the photogenerated carriers. This work may open up new opportunities for the design and construction of the high efficient and low-cost PEC water splitting system.
ABSTRACT
OBJECTIVE: To observe the effects of sacral canal injection in treating lumbar intervertebral disc herniation with different sections, types and courses, in order to provide selective basis for clinical indications. METHODS: From March 2007 to May 2011, 329 patients with lumbar intervertebral disc herniation were treated with sacral canal injection and their data were retrospectively analyzed. There were 178 males and 151 females,ranging in age from 16 to 78 years old with an average of 45 years; ranging in course of disease from 2 days to 41 years with an average of 4.1 years. All the protrusions were simple segment, and L3,4 of 51 cases, L4,5 of 142 cases, L5S1 of 136 cases including central protrusion of 137 cases, posterolateral of 145 cases, extreme posterolateral of 47 cases. According to different sections, types, courses (more than or less than 6 months ) of lumbar intervertebral disc herniation, the patients were divided into several groups, clinical effects of the groups were compared and analyzed. RESULTS: Clinical effect of protrusion in L5S1 group was better than that of L3,4, L4,5 group; the effect of patients with course less than 6 months was better than with course more than 6 months; effect of posterolateral protrution was better than that of central and extreme posterolateral protrusion. Clinical effect of corresponding the three conditions was better than that of others no corresponding the three conditions,the three conditions included the course less than 6 months, protrusion in L5S1 section, with type of posterolateral protrusion. No complications were found in all patients and cured patients were followed up for 1 year with the recurrence rate of 0.05%. CONCLUSION: The patients with short course, lower protrusion, type of posterolateral protrusion can obtained better effects, while the patients who meets the three conditions is appropriate mostly to sacral canal injection therapy.
