<p>Enhancing dimethyldichlorosilane production in Rochow-Muller reaction by adding ZnO-Sn-P co-promoter in CuO/SiO2</p>

Commercial nonsupported Cu-based catalysts have to be mixed with various promoters to enhance their catalytic performance in the Rochow-Muller reaction. However, considerable debates still exist at a fundamental level on how these promoters function. Herein, we systematically investigated the effects of ZnO, Sn, and P promoters on the catalytic property of the CuO/SiO2 catalyst for synthesizing dimethyldichlorosilane (M2) via the Rochow-Muller reaction. A series of CuO/SiO2 catalysts containing these promoters were prepared by the ball-milling method. The CuO/SiO2 catalyst with the coexistence of ZnO, P, and Sn promoters showed the highest catalytic activity, even superior to the commercial non supported Cu-based catalysts. Detailed characterizations showed the increased capability for oxygen adsorption on the CuO surface and dissociative chemisorption of methyl chloride led to the improved catalytic performance. This work deciphers the promoter mechanism and demonstrates a promising strategy for the efficient synthesis of M2.(C) 2022 Elsevier Inc. All rights reserved

<p>Enhancing dimethyldichlorosilane production in Rochow-Muller reaction by adding ZnO-Sn-P co-promoter in CuO/SiO2</p>

Commercial nonsupported Cu-based catalysts have to be mixed with various promoters to enhance their catalytic performance in the Rochow-Muller reaction. However, considerable debates still exist at a fundamental level on how these promoters function. Herein, we systematically investigated the effects of ZnO, Sn, and P promoters on the catalytic property of the CuO/SiO2 catalyst for synthesizing dimethyldichlorosilane (M2) via the Rochow-Muller reaction. A series of CuO/SiO2 catalysts containing these promoters were prepared by the ball-milling method. The CuO/SiO2 catalyst with the coexistence of ZnO, P, and Sn promoters showed the highest catalytic activity, even superior to the commercial non supported Cu-based catalysts. Detailed characterizations showed the increased capability for oxygen adsorption on the CuO surface and dissociative chemisorption of methyl chloride led to the improved catalytic performance. This work deciphers the promoter mechanism and demonstrates a promising strategy for the efficient synthesis of M2.(C) 2022 Elsevier Inc. All rights reserved

Childhood maltreatment is associated with larger left thalamic gray matter volume in adolescents with generalized anxiety disorder.

BACKGROUND: Generalized anxiety disorder (GAD) is a common anxiety disorder that usually begins in adolescence. Childhood maltreatment is highly prevalent and increases the possibility for developing a variety of mental disorders including anxiety disorders. An earlier age at onset of GAD is significantly related to maltreatment in childhood. Exploring the underpinnings of the relationship between childhood maltreatment and adolescent onset GAD would be helpful in identifying the potential risk markers of this condition. METHODS: Twenty-six adolescents with GAD and 25 healthy controls participated in this study. A childhood trauma questionnaire (CTQ) was introduced to assess childhood maltreatment. All subjects underwent high-resolution structural magnetic resonance scans. Voxel-based morphometry (VBM) was used to investigate gray matter alterations. RESULTS: Significantly larger gray matter volumes of the right putamen were observed in GAD patients compared to healthy controls. In addition, a significant diagnosis-by-maltreatment interaction effect for the left thalamic gray matter volume was revealed, as shown by larger volumes of the left thalamic gray matter in GAD patients with childhood maltreatment compared with GAD patients without childhood maltreatment as well as with healthy controls with/without childhood maltreatment. A significant positive association between childhood maltreatment and left thalamic gray matter volume was only seen in GAD patients. CONCLUSIONS: These findings revealed an increased volume in the subcortical regions in adolescent GAD, and the alterations in the left thalamus might be involved in the association between childhood maltreatment and the occurrence of GAD

Meteorological conditions and structures of atmospheric boundary layer in October 2004 over Pearl River Delta area

High-level concentrations of air pollutants usually occur in autumn and winter over Peal River Delta (PRD), China. Atmospheric boundary layer observations were carried out at Qingyuan, Panyu and Xinken in PRD in October 2004. Wind speed, wind direction, air temperature and aerosol characteristics were measured by radio soundings and Raman LIDAR. The observational results showed that surface high-pressure system (anti-cyclone), descent motion outside of hurricane and sea breeze would result in the high-level concentrations. The averaged height of atmospheric boundary layer in nighttime was about 200 m, while in day time the maximal value was about 1200 m. The aerosol layer typically reached up to 1.5-3.0 km. The averaged aerosol optical depth was 0.91 at 532 nm wavelength and aerosol mainly originated from fossil fuel and biomass-burning emissions. The presence of anti-cyclone high-pressure systems and sea breeze lead to the formation of three inversion layers and two aerosol layers as well as quite specific vertical profiles of the wind velocity over Xinken station.Peer reviewe

Interface Engineering of Hollow CoO/Co₄S₃@CoO/Co₄S₃ Heterojunction for Highly Stable and Efficient Electrocatalytic Overall Water Splitting

The key to improve the performance of electrochemically water splitting and simplify the entire system is to develop a dual-functional catalyst, which can be applied to catalyze the process of HER and OER. Therefore, we synthesized a novel hollow CoO/Co4S3@CoO/Co4S3 heterojunction with a core–shell structure as an excellent dual-functional catalyst. This sample is composed of an outer hollow CoO/Co4S3 cubic thin shell and an inner hollow CoO/Co4S3 sphere, and it can provide abundant catalytic active sites while effectively promoting the flow of reactants, products, and electrolytes. Meanwhile, the O–Co–S bond in the heterojunction interface can promote both the CoO active site in OER and theCo4S3 active site in HER. Therefore, the overpotential of the hollow CoO/Co4S3@CoO/Co4S3 is only 190 mV (OER) and 81 mV (HER), respectively, at the current density of 10 mA cm–2. Moreover, the hollow CoO/Co4S3@CoO/Co4S3 showed the outstanding electrochemical stability in 60 h. In addition, in the two-electrode system assembled from the hollow CoO/Co4S3@CoO/Co4S3, only the potential of 1.48 V can achieve the current density of 10 mA cm–2. Impressively, the commercial solar panel is sufficient to drive the two-electrode electrolyzer consisting of hollow CoO/Co4S3@CoO/Co4S3. This finding offers a promising nonprecious metal-based catalyst that can be applied to catalyze the electrochemical overall water splitting

Ni-Ni3P/SiO2 Catalyst for Highly Selective Production of Silicon Tetrachloride via Silicon Hydrochlorination

: SiHCl3 (TCS) and SiCl4 (STC), important chlorosilanes in the silicon industry, are currently produced by noncatalytic silicon hydrochlorination with a selectivity of 85% for TCS and 15% for STC approximately. It is a significant challenge to selectively produce TCS and STC with the desired ratio in one reactor to realize flexible manufacturing that meets the periodic market demands. In the present work, we develop a novel Ni-Ni3P/ SiO2 catalyst using a simple reduction synthesis method to produce STC selectively in Si hydrochlorination. The catalyst performance is evaluated under different industrial operating conditions. It shows that the Ni-Ni3P/SiO2 catalyst exhibits a selectivity higher than 90% for STC and a selectivity of <10% for TCS under the optimal conditions. The calculations based on the density functional theory show that P-modified Ni-based catalysts promote the breakage of HCl bonds and make the product favor STC instead of TCS. Therefore, it is possible to realize flexible manufacture of TCS and STC in one reactor by combining the CuO-based catalysts reported in our previous work to enhance TCS production and the Ni-Ni3P/SiO2 catalyst developed in this work to promote STC production

Interface Engineering of Hollow CoO/Co₄S₃@CoO/Co₄S₃ Heterojunction for Highly Stable and Efficient Electrocatalytic Overall Water Splitting

The key to improve the performance of electrochemically water splitting and simplify the entire system is to develop a dual-functional catalyst, which can be applied to catalyze the process of HER and OER. Therefore, we synthesized a novel hollow CoO/Co4S3@CoO/Co4S3 heterojunction with a core–shell structure as an excellent dual-functional catalyst. This sample is composed of an outer hollow CoO/Co4S3 cubic thin shell and an inner hollow CoO/Co4S3 sphere, and it can provide abundant catalytic active sites while effectively promoting the flow of reactants, products, and electrolytes. Meanwhile, the O–Co–S bond in the heterojunction interface can promote both the CoO active site in OER and theCo4S3 active site in HER. Therefore, the overpotential of the hollow CoO/Co4S3@CoO/Co4S3 is only 190 mV (OER) and 81 mV (HER), respectively, at the current density of 10 mA cm–2. Moreover, the hollow CoO/Co4S3@CoO/Co4S3 showed the outstanding electrochemical stability in 60 h. In addition, in the two-electrode system assembled from the hollow CoO/Co4S3@CoO/Co4S3, only the potential of 1.48 V can achieve the current density of 10 mA cm–2. Impressively, the commercial solar panel is sufficient to drive the two-electrode electrolyzer consisting of hollow CoO/Co4S3@CoO/Co4S3. This finding offers a promising nonprecious metal-based catalyst that can be applied to catalyze the electrochemical overall water splitting

Interface Engineering of Hollow CoO/Co₄S₃@CoO/Co₄S₃ Heterojunction for Highly Stable and Efficient Electrocatalytic Overall Water Splitting

The key to improve the performance of electrochemically water splitting and simplify the entire system is to develop a dual-functional catalyst, which can be applied to catalyze the process of HER and OER. Therefore, we synthesized a novel hollow CoO/Co4S3@CoO/Co4S3 heterojunction with a core–shell structure as an excellent dual-functional catalyst. This sample is composed of an outer hollow CoO/Co4S3 cubic thin shell and an inner hollow CoO/Co4S3 sphere, and it can provide abundant catalytic active sites while effectively promoting the flow of reactants, products, and electrolytes. Meanwhile, the O–Co–S bond in the heterojunction interface can promote both the CoO active site in OER and theCo4S3 active site in HER. Therefore, the overpotential of the hollow CoO/Co4S3@CoO/Co4S3 is only 190 mV (OER) and 81 mV (HER), respectively, at the current density of 10 mA cm–2. Moreover, the hollow CoO/Co4S3@CoO/Co4S3 showed the outstanding electrochemical stability in 60 h. In addition, in the two-electrode system assembled from the hollow CoO/Co4S3@CoO/Co4S3, only the potential of 1.48 V can achieve the current density of 10 mA cm–2. Impressively, the commercial solar panel is sufficient to drive the two-electrode electrolyzer consisting of hollow CoO/Co4S3@CoO/Co4S3. This finding offers a promising nonprecious metal-based catalyst that can be applied to catalyze the electrochemical overall water splitting

Tailoring the Electronic Structure of Single Ag Atoms in Ag/WO3 for Efficient NO Reduction by CO in the Presence of O2

Developing efficient catalysts for the selective catalytic reduction of NOx by CO (CO-SCR) is the key challenge for commercializing this technology. Ag-based catalysts with relatively low costs are promising but widely believed to be not efficient enough for this reaction. Here, we demonstrate that atomically dispersed Ag supported on ordered mesoporous WO3 (mWO3) can serve as a highly active catalyst for CO-SCR under O2-containing conditions. By altering the amount of the Ag precursor, the local environment of the Ag atom coordinated with the O atom can be tailored. Furthermore, at 250 degrees C and an O2/CO ratio of 2.5:1, 0.3Ag/m-WO3 (0.3 wt % Ag) with six-coordinated Ag-O exhibited much better catalytic performance than 5 Ag/m-WO3 (5 wt % Ag) with two coordinated Ag-O (e.g., 0.43 vs 0.02 molNO gAg -1 h-1 in the reaction rate) and previously reported Ag-based catalysts in the literature. The theoretical calculations confirm that the six-coordinated Ag atoms in 0.3Ag/m-WO3 possess a more positive oxidation state and a higher d-band center than the two-coordinated Ag atoms in 5Ag/m-WO3, promoting its bonding strength with co adsorption of the critical intermediates of N2O* and CO*. This work provides a feasible route for regulating the local environment of a Ag single atomic catalyst to enhance its catalytic property for CO-SCR