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Two Mn0.15Ce0.85O2−δ mixed oxides were synthesized by a co-precipitation method using Mn(NO3)2 and KMnO4 as the manganese precursors, respectively. Structural analyses by X-ray powder diffraction and Raman spectroscopy reveal the formation of MnOx-CeO2 solid solutions. The Mn0.15Ce0.85O2−δ catalyst prepared from the high-valent manganese precursor exhibits higher activity for the catalytic oxidation of NO. The advantage of KMnO4 is related to the improved redox property of the catalyst as supported by H2 temperature-programmed reduction (TPR) and O2 temperature-programmed desorption (TPD). The Mn-Ce interactions create more Mn4+, Ce3+ and oxygen vacancies on the KMnO4-synthesized mixed oxides based on the Raman and X-ray photoelectron spectra (XPS). [ABSTRACT FROM AUTHOR]

This study aimed to identify which element of body composition measurements taken before 17th week gestation was the strongest risk factor for gestational diabetes mellitus (GDM) in Chinese pregnant women. A retrospective study was performed using data retrieved from the Electronic Medical Record database of Chongqing Health Center for Women and Children (China) from January 2014 to December 2015. A total of 22,223 women were included with singleton pregnancies and no preexisting diabetes who underwent bioelectrical impedance analysis (BIA) before 17 gestational weeks and 75-g OGTT at 24–28 gestational weeks. The prevalence of GDM from 2014 to 2015 was 27.13% (IADPSG). All indicators of BIA (total body water, fat mass, fat-free mass, percent body fat, muscle mass, visceral fat levels, proteins, bone minerals, basal metabolic rate, lean trunk mass), age, weight and body mass index (BMI) were risk factors that significantly increased the occurrence of GDM (p <.001 for all). Women older than 30 years or with a BMI more than 23, had a significantly higher GDM prevalence (34.89% and 34.77%). After adjusted covariates, visceral fat levels at the third quartile, the ORs of GDM were 1.142 (95% CI 1.032–1.263) in model I and 1.419 (95% CI 1.274–1.581) in model II used the first quartile as reference (p <.05 for both); bone minerals at the third quartile, the ORs of GDM were 1.124 (95% CI 1.020–1.238) in model I and 1.311 (95% CI 1.192–1.442) in model II (p <.05 for both). After adjusted for age, visceral fat levels and bone minerals, OR of GDM for percent body fat more than 28.77% at the third quartile was 1.334 (95% CI 1.201–1.482) in model II (p <.05 for both). Visceral fat levels, bone minerals and percent body fat were significantly associated with an increased risk of GDM, providing the reference ranges of visceral fat levels, bone minerals and percent body fat as predictive factors for Chinese women to estimate the risk of GDM by BIA during pregnancy. [ABSTRACT FROM AUTHOR]

In this study, a V2O5-Sb2O3/TiO2 monolithic catalyst was modified by introducing WO3. The WO3-modified catalyst exhibited enhanced catalytic activity in the measuring temperature range of 175–320 °C. The changes in dispersion of vanadia species were investigated by ultraviolet-visible (UV-Vis) spectroscopy and H2 temperature-programmed reduction (H2-TPR). A durability test was conducted in a wet SO2-containing atmosphere at 220 °C for 25 h. The sulfate deposition was estimated by temperature-programmed decomposition (TPDC) of sulfates, thermo-gravimetric (TG) analysis, and temperature-programmed desorption (TPD) of NH3. Isothermal SO2 oxidation and temperature-programmed surface reaction (TPSR) of NH4HSO4 with NO were performed. Based on these characterizations, effects of WO3 modification on the sulfate tolerance of the catalyst were explored. [ABSTRACT FROM AUTHOR]

TiO2 has been considered as an ideal photocatalyst for water splitting. However, narrow light absorbance, low charge separation efficiency, and rare surface active sites lead to the low photocatalytic efficiency of TiO2. Although extensive research attempted to improve the situation, there is still lack of method for constructing high active and noble-metal-free TiO2 photocatalyst for H2 evolution reactions (HER). In this work, we loaded single atomic (SA) Ni (or Co) on the surface of anatase TiO2 (TiO2(A)) nanosheets by an isolation strategy. Ethylene diamine tetraacetic acid and ethylene glycol (EDTA-EG) compounds were used to chelate metal ions in solution and form carbon quantum dots in the following thermal treatment to isolate the metal ions on surface of TiO2(A). The prepared Ni SA/TiO2(A) catalyst owned a "skin wrapped body" structure with in-situ formed two-dimensional (2D) heterojunction facilitating the fast electron transfer. As a result, the Ni SA/TiO2(A) catalyst showed a high H2 evolution rate of 2,900 µmol·g−1·h−1. This work provides an isolation strategy for constructing promising single-atom metal catalyst for photocatalysis and beyond. [ABSTRACT FROM AUTHOR]

Noble metal-free MoS2/g-C3N4 photocatalysts have been synthetized by one step thermal treatment of thiourea and sodium molybdate, which has intimate contact interfaces between g-C3N4 and MoS2. The hydrogen generation rate of MoS2/g-C3N4 photocatalyst is 280 µmol·g−1·h−1, 40 times as that of pristine g-C3N4. The enhanced activity is attributed to the in-situ generated intimate interfaces, which leads to enhanced absorption of visible light and higher efficiency of charges separation. [ABSTRACT FROM AUTHOR]