In adults treated with hemodialysis, poorer dental health was associated with early death, whereas preventive dental health practices were associated with longer survival.

TiO 2 hollow structures (HS) were synthesized by carbon sphere template removal method. Nanometer sized carbon spheres (CS) were prepared by mild hydrothermal treatment of ordinary table sugar (sucrose). The size of these spheres can be controlled by the parameters of the hydrothermal treatment (e.g. time and pH). The obtained CSs were characterized by scanning electron microscopy (SEM), Raman spectroscopy, infrared spectroscopy (IR), X-ray diffraction (XRD) and thermogravimetry (TG). CSs were successfully coated with TiO 2 via sol-gel method. The phase composition of the TiO 2 hollow spheres were controlled by the annealing temperature during crystallization and CSs template removal. TiO 2 hollow structures (HSs) were characterized by SEM, XRD, Raman spectroscopy, TG and energy-dispersive X-ray spectroscopy (EDX). Photocatalytic performance of the TiO 2 HSs was evaluated by phenol degradation in a batch-type foam reactor under low powered UV-A irradiation. The degradation reaction was followed by high-performance liquid chromatography (HPLC) and total organic carbon (TOC) measurement techniques. Photocatalytic activity test results pointed out that increased rutile content up to a certain extent (resulting mixed phase anatase-rutile TiO 2) effects advantageously the photocatalytic performance of TiO 2 HSs and the unique morphology proved to enhance the photocatalytic activity (six times) as well as TOC removal efficiency (twelve times) compared to the sample which was prepared by the same method without the CSs.

Carbon nanospheres (CNSs) were prepared by hydrothermal synthesis, and coated with TiO2 and ZnO nanofilms by atomic layer deposition. Subsequently, through burning out the carbon core templates hollow metal oxide nanospheres were obtained. The substrates, the carbon-metal oxide composites and the hollow nanospheres were characterized with TG/DTA-MS, FTIR, Raman, XRD, SEM-EDX, TEM-SAED and their photocatalytic activity was also investigated. The results indicate that CNSs are not beneficial for photocatalysis, but the crystalline hollow metal oxide nanospheres have considerable photocatalytic activity.

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Rationale Complete decomposition of silicate rock matrices is crucial in determining their isotopic compositions, but acid dissolution in a high‐pressure steel‐jacketed bomb, which has been the only powerful, effective technique thus far, is time‐consuming and expensive. Rock dissolution using ammonium bifluoride (ABF), as described here, is a viable alternative. Methods Geological reference materials (GRMs) were digested using ABF in closed Teflon beakers at temperatures of 220/230°C in a convection oven and subsequently treated with HNO3. Hf‐Sr‐Nd were separated and purified using ion‐exchange chemistry columns calibrated for 50–2 mg samples. The isotopic compositions of Sr‐Nd were measured by Thermal Ionization Mass Spectrometry, while that of Hf by Multi‐Collector Inductively Coupled Plasma Mass Spectrometry, both with normal 1011 Ω and gain calibrated 1013 Ω amplifiers. Results Total procedural blanks of our protocol are 0.5 ng for Sr, 0.2 ng for Nd and <25 pg for Hf. Test runs with GRMs, ranging in composition from basic to felsic and dissolved in ABF, yield accurate 87Sr/86Sr, 143Nd/144Nd and 176Hf/177Hf isotope ratios as compared with those obtained with the bomb dissolution technique. Reproducibilities were comparable, on the order of 10–20 ppm. Our technique allows combined Hf‐Sr‐Nd isotope analyses of low‐mass (50–2 mg) samples. Conclusions The ABF digestion is an alternative technique to high‐pressure bomb dissolution in matrix decomposition for accurate and reproducible Hf‐Nd‐Sr isotope analyses of geological samples within a reasonable time (3–4 days), with high sample throughput and low costs in geochemistry and environmental sciences.