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Catalytic ozonation is a new method used for removal of NH4OH solution. Therefore, high catalytic performance (activity and selectivity) should be achieved. In this work, we report the synthesis and catalytic performance of Fe2O3-Co3O4 modified dolomite in the catalytic ozonation of NH4OH solution. Dolomite was successfully activated and modified with Fe2O3 and Co3O4. Firstly, dolomite was activated by heating at 800°C for 3 h and followed by KOH treatment. Activated dolomite was modified with Fe2O3 by the atomic implantation method using FeCl3 as Fe source. Fe2O3 modified dolomite was further modified with Co3O4 by precipitation method. The obtained catalysts were characterized by X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), energy-dispersive X-ray spectroscopy (EDS), scanning electron microscopy (SEM), N2 adsorption–desorption (BET), and temperature-programmed reduction (H2-TPR). From SEM image, it was revealed that nano-Fe2O3 and Co3O4 particles with the size of 80–120 nm. Catalytic performance of activated dolomite, Fe2O3 modified dolomite, and Fe2O3-Co3O4 modified dolomite in catalytic ozonation of NH4+ solution was investigated and evaluated. Among 3 tested catalysts, Fe2O3-Co3O4 modified dolomite has the highest NH4+ conversion (96%) and N2 selectivity (77.82%). Selectivity toward N2 over the catalyst was explained on the basis of bond strength M-O in oxides through the standard enthalpy Δ H ° f of oxide. Catalyst with lower Δ H ° f value has higher N2 selectivity and the order is the following: Co3O4 (Δ H ° f of 60 kcal (mole O)) > Fe2O3 (Δ H ° f of 70 kcal (mole O)) > MgO (Δ H ° f of 170 kcal (mole O)). Moreover, high reduction ability of Fe2O3-Co3O4 modified dolomite could improve the N2 selectivity by the reduction of NO3- to N2 gas. [ABSTRACT FROM AUTHOR]

Photoelectrochemical devices based on p-type nanostructured semiconducting materials show strong potentialities for various applications, such as photovoltaics and photocatalysis. While only one study was reported on the use of the reference dye P1 for solid-state p-type dye-sensitized solar cells (DSSC), in this work we have systematically investigated two diketopyrrolopyrrole (DPP) derivatives as sensitizers for solid-state p-type DSSC based on NiO and [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) as solid-state electron transporter material. We report on the performance in solid-state p-type DSSC of a simple DPP dye bearing a thienyl carboxylic acid as the binding group and a parent compound substituted by a pyromellitimide (PYRO) playing the role of a secondary inner electron acceptor. By focusing on the dye/PCBM interface, we specifically show using transient photoluminescence measurements that the presence of a secondary electron acceptor unit can efficiently favor the formation of the (dye+/PCBM-) state, owing to its significant reducing ability and lifetime of the charge separated state. As a consequence, using these DPP derivatives leads to unprecedented photocurrents up to 0.45 mA cm-2, which are 10 times larger than previously reported values for the system based on P1. Our analysis also demonstrates the strong correlation between the ability of the dyes to efficiently generate charge carriers and the resulting photocurrents. [ABSTRACT FROM AUTHOR]

Introduction: Several studies have reported women's worry that sexual intercourse may harm the course of pregnancy. This worry might lead to avoidance of sexual intercourse during pregnancy., Aim: To assess if fears about harming the pregnancy are associated with avoidance of sexual intercourse during pregnancy., Methods: A cross-sectional study was conducted on 250 Vietnamese pregnant women in the first or second trimester who visited our hospital for antenatal care. We explored 5 types of fears including miscarriage/preterm labor, premature rupture of membranes, bleeding, infection, and injury to the fetus. Fears were measured by modified questions from the Reasons For Not Engaging in Sexual Activity During Pregnancy questionnaire. Using the total fear score, pregnant women were categorized into having low, moderate, and high fear., Main Outcome Measure: Not having sexual intercourse during the past 4 weeks., Results: 72 (28.8%) pregnant women had no sexual intercourse for the past 4 weeks. All types of fear were considered important among pregnant women; the more important fears were infection and injury to the fetus. In multivariable regression analysis, the prevalence of not having sexual intercourse was higher in both women who had moderate (adjusted prevalence ratio = 2.84, 95% CI 1.42-5.67) and high fear (adjusted prevalence ratio = 4.39, 95% CI 2.28-8.44)., Conclusion: Avoidance of sexual intercourse was common among Vietnamese pregnant women and was associated with the fears about harming the pregnancy. This can be a target in the health education programs for pregnancy couples. Thanh C. Phan, Long B. Hoang, Thanh K. Tran, et al. Fear-Related Reasons for Avoiding Sexual Intercourse in Early Pregnancy: A Cross-Sectional Study. Sex Med 2021;9:100430., (Copyright © 2021 International Society for Sexual Medicine. Published by Elsevier Inc. All rights reserved.)