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BackgroundCurrent literature describes limited and controversial evidence on the associations between maternal preconception and first trimester exposure to particulate matter with a diameter ≤10 µm (PM10) and the risk of oral cleft (OC).MethodsWe conducted a case–control study involving 3086 OC cases and 7950 controls, registered in the Maternal and Child Health Certificate Registry in Liaoning Province between 2010 and 2015. PM10concentrations were obtained from the Environment Protection Bureau. The exposure windows included the 3 months before pregnancy, the first trimester and the individual months. Unconditional logistic regression model was performed to estimate the OR and 95% CI for the association between PM10exposure and the risk of OC, cleft lip only (CLO), cleft palate only (CPO), and cleft lip and palate (CLP).ResultsMaternal PM10exposure was positively associated with an increased risk for OC during the 3 months preconception (per 10 µg/m3increment: OR=1.04, 95% CI 1.01 to 1.07; highest vs lowest quartile: OR=1.23, 95% CI 1.04 to 1.45) and the first trimester (per 10 µg/m3increment: OR=1.05, 95% CI 1.02 to 1.08; highest vs lowest quartile: OR=1.37, 95% CI 1.15 to 1.64). Analyses based on individual months presented similar positive associations, particularly in the second month of pregnancy (OR=1.77, 95% CI 1.51 to 2.09) for highest versus lowest quartile. In the subtype analysis, stronger associations were observed for CLO, whereas there was negligible evidence for CPO and CLP. Sensitivity analyses using propensity score matching generated similar findings.ConclusionsOur study provides evidence that PM10exposure during the 3 months preconception and the first trimester increases the risk of OC.

0.1%Tb3+ and 0.2%Sm3+ co-doped TiO2 have been prepared by sol-gel method and characterized by the techniques such as XRD and SEM/EDAX. The photocatalytic degradation of Methylene blue in aqueous solution was used as a probe reaction to evaluate their photocatalytic activity. The effects of process parameters like, pH and initial methylene blue concentration on the extent of photodegradation have been investigated. The results show when the solution is at pH 7, with initial methylene blue concentration of 4 mg/L, the photodegradation is best. Key words:

Pure BiVO4, single doped and co-doped BiVO4 have been prepared by chemical precipitation method and characterized by the techniques such as XRD and SEM/EDAX. The photocatalytic degradation of methylene blue (MB) in aqueous solution was used as a probe reaction to evaluate pure BiVO4, single doped BiVO4 and co-doped BiVO4 photocatalytic activity. The results show that doping of single doped and co-doped significantly enhance the photocatalytic activity of BiVO4. When the 0.1%Gd3+ and 0.2%Sm co-doped, the BiVO4 degradation rate reaches 91%.

Abstract: The 0.05%Eu3+ and 0.1%Sm3+ co-doped TiO2 composite nanoparticles have been prepared by sol-gel method and characterized by the techniques such as XRD and SEM/EDAX. The photocatalytic degradation of Methylene blue in aqueous solution was used as a probe reaction to evaluate their photocatalytic activity. The effects of process parameters like, solution pH and H2O2 concentration on the extent of photodegradation have been investigated.

Pure BiVO4, Sm doped BiVO4 have been prepared by chemical precipitation method and characterized by the techniques such as XRD and SEM. The photocatalytic degradation of methylene blue (MB) in aqueous solution was used as a probe reaction to evaluate pure BiVO4, Sm doped BiVO4 photocatalytic activity. The results show that doping of Sm decreases the diameter of BiVO4 nano-particles and significantly enhance the photocatalytic activity of BiVO4. When the 0.2% Sm doped, the BiVO4 degradation rate reaches 92.8%.

The 0.05%Gd3+ /0.4%Eu3+ co-doped TiO2 composite nanopowders have been prepared by sol-gel method and characterized by the techniques such as XRD, SEM/EDAX. The photocatalytic degradation of Methylene blue in aqueous solution was used as a probe reaction to evaluate their photocatalytic activity. The results show that the 0.05%Gd3+ /0.4%Eu3+ co-doped TiO2 are only structuresd by anatase phase with grain sizes of about 16nm at 540 ℃ for 4 h. The photocatalutic degradation of Methylene blue was 96.7% in 120 min of irradiation when the pH value was 9.

TiO2 and Sn4+-doped TiO2 were prepared by sol-gel method and characterized by the techniques such as XRD, SEM and DRS. The photocatalytic degradation of methylene blue (MB) in aqueous solution was used as a probe reaction to evaluate their photocatalytic activity. The matrix distortion of TiO2 increases after Sn4+ doping and a blue-shift of the absorption profile are clearly observed. The results show that doped Sn4+ inhibits the phase transformation of TiO2 from anatase to rutile, decreases the diameter of TiO2 and significantly enhance the photocatalytic activity of TiO2. The Sn4+-doped into TiO2 exert a synergistic effect on their photocatalytic activity.

Pure TiO2, Sm3+ and Gd3+ co-doping TiO2 have been prepared by sol-gel method and characterized by the techniques such as XRD and SEM. The photocatalytic degradation of methylene blue (MB) in aqueous solution was used as a probe reaction to evaluate Pure TiO2, Sm3+ and Gd3+ co-doping TiO2 photocatalytic activity. The matrix distortion of TiO2 increases after co-doping of Sm3+ and Gd3+ are clearly observed. The results show that co-doping of Sm3+ and Gd3+ inhibits the phase transformation of TiO2 from anatase to rutile, decreases the diameter of TiO2 nano-particles and significantly enhance the photocatalytic activity of TiO2. When the co-doped amounts for Sm3+ and Gd3+ are 0.1% and 0.2%, its degradation rate reaches 99%.

Pure TiO2, Eu3+ and Sm3+ co-doping TiO2 composite nanoparticles have been prepared by sol-gel method and characterized by the techniques such as XRD, SEM and DRS. The photocatalytic degradation of methylene blue (MB) in aqueous solution was used as a probe reaction to evaluate their photocatalytic activity. The matrix distortion of TiO2 nano-particles increases after co-doping of Eu3+ and Sm3+ and a blue-shift of the absorption profile are clearly observed. The results show that co-doping of Eu3+ and Sm3+ inhibits the phase transformation of TiO2 from anatase to rutile, decreases the diameter of TiO2 nano-particles and significantly enhance the photocatalytic activity of TiO2. The Eu3+ and Sm3+ co-doped into TiO2 nano-particles exert a synergistic effect on their photocatalytic activity.