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In this reported work, lotus leaves‐derived biochar (LBC) was modified using various chemical methods. LBC prepared by different modification methods was used as the carrier for the development of low‐temperature selective catalytic reduction (SCR) catalysts. A comparative study of low‐temperature SCR manganese catalysts based on LBC chemically modified using NaOH, HNO3 and hexadecylcetyltrimethylammonium bromide (CTAB) was performed, revealing different deNOx performance of these catalysts. For the supported catalysts, the 25%Mn/LBC‐OH catalyst appeared to be optimum since it exhibited over 95% NOx conversion at 225 °C with a space velocity of 37 500 h−1. The microstructure, phase composition, redox properties and surface acidity were determined using field emission scanning electron microscopy, Brunauer–Emmett–Teller surface area, X‐ray diffraction, H2‐temperature‐programmed reduction, NH3‐temperature‐programmed desorption, and so forth. The results showed that the excellent SCR performance of 25%Mn/LBC‐OH was closely related to its abundant high valence Mn, suitable surface acidity and high redox capability. More importantly, highly dispersed MnOx easily formed on the surface of the LBC‐OH support, which was the key factor in the excellent catalytic activity of 25%Mn/LBC‐OH catalyst. Furthermore, the highly dispersed 25%Mn/LBC‐OH catalyst also exhibited improved tolerance to SO2 and H2O, making this catalyst a good candidate for reducing the NOx emission from coal‐fired power plants. © 2022 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

To eliminate nitrogen oxides (NOx), composite carrier-supported catalysts (Mn-Ce/MWCNT-W) and traditional catalysts (Mn-Ce/MWCNT and W-Mn-Ce/MWCNT) were prepared using an ultrasonic impregnation method that preformed low-temperature ammonia-selective catalytic reduction (SCR) removal of NOx. The promotion effects of MWCNT-W composite carriers for low temperature SCR activities and SO2 tolerance of the catalysts were systematically investigated. Compared to traditional catalyst, Mn-Ce/MWCNT-W catalyst, with a 30% WOx/MWCNT mass ratio, demonstrated improved SCR activity and high N2-selectivity from 100°C to 200°C. A series of characterizations were carried out and it was found that there were more redox sites and the stronger the NH3 adsorption capacity over the composite carrier-supported catalysts than traditional catalysts. Also, with this composite carrier-supported catalyst, the improvement of SCR reaction was considered to be from the abundance of high valence state Mn and well dispersed active components. Notably, compared to traditional catalyst, the composite carrier-supported catalyst exhibited the stronger sulfur resistance. Thus, using MWCNT-W composite carriers to prepare Mn-Ce/MWCNT-W catalysts resulted in excellent NOx conversion and SO2 resistance at low temperatures. Implications: LT NH3-SCR of NOx is an effective way to remove NOx from stationary sources. The physicochemical properties of the support not only affect a catalyst's LT SCR activity but also affect the catalyst's anti-poisoning performance. The modified carriers could promote active component dispersion, which is conducive to SCR reaction. However, for LT SCR reactions, few reports have addressed the design and preparation of composite carrier-supported catalysts. The goal of this study was to design and synthesize Mn-Ce/MWCNT-W catalysts and to observe the influence of composite support in Mn-based catalysts on LT SCR activity and sulfur resistance. [ABSTRACT FROM AUTHOR]

DOPO and boron nitride (BN) fillers with different particle sizes and several loadings were employed to improve the properties of cyanate ester (CE) resin. The effects of BN content and particle size on the thermal conductivity of the BN‐DOPO/CE ternary composites were discussed. The influence of enhancing the thermal conductivity of the ternary composites on their flame retardancy was studied. The consequences showed that increasing the thermal conductivity of BN‐DOPO/CE composites had an active impact on their flame retardancy. Approving flame retardancy of the ternary composites was certified by the high limiting oxygen index (LOI), UL‐94 rating of V‐0, and low heat release rate (HRR) and total heat release (THR). For instance, in contrast with pure CE matrix, peak of HRR (pk‐HRR), average of HRR (av‐HRR), THR, and average of effective heat of combustion (av‐EHC) of CEP/BN0.5 μm/10 composite were decreased by 51.7%, 33.8%, 18.7%, and 18.9%, respectively. Thermal gravimetry analysis (TGA) showed that the addition of BN fillers improves the thermal stability of the composites. Moreover, the ternary composites possess good dielectric properties. Their dielectric constants (ε) are less than 3, and dielectric loss tangent (tgδ) values are lower than neat CE resin. [ABSTRACT FROM AUTHOR]

To eliminate nitrogen oxides (NOx), composite carrier-supported catalysts (Mn-Ce/MWCNT-W) and traditional catalysts (Mn-Ce/MWCNT and W-Mn-Ce/MWCNT) were prepared using an ultrasonic impregnation method that preformed low-temperature ammonia-selective catalytic reduction (SCR) removal of NOx. The promotion effects of MWCNT-W composite carriers for low temperature SCR activities and SO2 tolerance of the catalysts were systematically investigated. Compared to traditional catalyst, Mn-Ce/MWCNT-W catalyst, with a 30% WOx/MWCNT mass ratio, demonstrated improved SCR activity and high N2-selectivity from 100°C to 200°C. A series of characterizations were carried out and it was found that there were more redox sites and the stronger the NH3 adsorption capacity over the composite carrier-supported catalysts than traditional catalysts. Also, with this composite carrier-supported catalyst, the improvement of SCR reaction was considered to be from the abundance of high valence state Mn and well dispersed active components. Notably, compared to traditional catalyst, the composite carrier-supported catalyst exhibited the stronger sulfur resistance. Thus, using MWCNT-W composite carriers to prepare Mn-Ce/MWCNT-W catalysts resulted in excellent NOx conversion and SO2 resistance at low temperatures. Implications: LT NH3-SCR of NOx is an effective way to remove NOx from stationary sources. The physicochemical properties of the support not only affect a catalyst's LT SCR activity but also affect the catalyst's anti-poisoning performance. The modified carriers could promote active component dispersion, which is conducive to SCR reaction. However, for LT SCR reactions, few reports have addressed the design and preparation of composite carrier-supported catalysts. The goal of this study was to design and synthesize Mn-Ce/MWCNT-W catalysts and to observe the influence of composite support in Mn-based catalysts on LT SCR activity and sulfur resistance. [ABSTRACT FROM AUTHOR]

Mesoporous Mn-doped Co 3 O 4 catalysts were successfully prepared via a dry soft reactive grinding method based on solid state reaction, and their catalytic performances on CO oxidation were evaluated at a high space velocity of 49,500 mL g −1 h −1 . A significant promoted effect was observed once the atomic ratios of Mn/(Co+Mn) were lower than 10%, for instance, the temperature for 50% conversion decreased to about −60 °C, showing superior catalytic performance compared to the single metal oxide. Especially, the Mn-promoted Co 3 O 4 catalyst with a Mn/(Co+Mn) molar ratio of 10% could convert 100% CO after 3000 min of time-on-steam without any deactivation at room temperature. As prepared catalysts were characterized by XRD, N 2 -adsorption/desorption, TEM, H 2 -TPR, O 2 -TPD and CO-titration analysis. The significant enhancement of performance for oxidation of CO over Mn-Co-O mixed oxides was associated with the high active oxygen species concentrations formed during the pretreatment in O 2 atmosphere. [ABSTRACT FROM AUTHOR]

Various urchin-like MnO 2 materials were obtained with a facile hydrothermal method through controlling the Mn precursor, reaction time, and reaction temperature. The property of MnO 2 materials was characterized by scanning electron microscopy, X-ray diffraction, and H 2 temperature-programmed reduction. The results showed that the Mn precursor could significantly impact the morphology of as-prepared MnO 2 . When the precursor was Mn(CH 3 COO) 2 ·4H 2 O, the MnO 2 morphology consisted of tennis-like microspheres assembled by nanorods. While the precursor was MnCl 2 ·4H 2 O, the sample morphology was a chestnut shell, and the samples were sea urchin microspheres, as the precursor was MnSO 4 ·H 2 O. At the same time, the morphology of MnO 2 was affected by hydrothermal time and temperature. The nanoneedles on the microsphere surface gradually lengthened with increasing hydrothermal time and hydrothermal temperature, until nanowires were formed. MnO 2 crystallinity was also influenced by hydrothermal temperature. It was γ-MnO 2 as the temperature was 50 and 80 °C while evolved to be α-MnO 2 and β-MnO 2 when the temperature increased to 140 °C. As MnO 2 (MnO 2 -1 h, MnO 2 -2 h, MnO 2 -4 h, and MnO 2 -6 h) was prepared to degrade toluene, all the samples could completely catalyze toluene at the temperature of 225 °C. However, the MnO 2 -4 h showed the best catalytic effect at a lower temperature., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

To eliminate nitrogen oxides (NO x ), composite carrier-supported catalysts (Mn-Ce/MWCNT-W) and traditional catalysts (Mn-Ce/MWCNT and W-Mn-Ce/MWCNT) were prepared using an ultrasonic impregnation method that preformed low-temperature ammonia-selective catalytic reduction (SCR) removal of NO x . The promotion effects of MWCNT-W composite carriers for low temperature SCR activities and SO 2 tolerance of the catalysts were systematically investigated. Compared to traditional catalyst, Mn-Ce/MWCNT-W catalyst, with a 30% WO x /MWCNT mass ratio, demonstrated improved SCR activity and high N 2 -selectivity from 100°C to 200°C. A series of characterizations were carried out and it was found that there were more redox sites and the stronger the NH 3 adsorption capacity over the composite carrier-supported catalysts than traditional catalysts. Also, with this composite carrier-supported catalyst, the improvement of SCR reaction was considered to be from the abundance of high valence state Mn and well dispersed active components. Notably, compared to traditional catalyst, the composite carrier-supported catalyst exhibited the stronger sulfur resistance. Thus, using MWCNT-W composite carriers to prepare Mn-Ce/MWCNT-W catalysts resulted in excellent NO x conversion and SO 2 resistance at low temperatures. Implications : LT NH 3 -SCR of NO x is an effective way to remove NO x from stationary sources. The physicochemical properties of the support not only affect a catalyst's LT SCR activity but also affect the catalyst's anti-poisoning performance. The modified carriers could promote active component dispersion, which is conducive to SCR reaction. However, for LT SCR reactions, few reports have addressed the design and preparation of composite carrier-supported catalysts. The goal of this study was to design and synthesize Mn-Ce/MWCNT-W catalysts and to observe the influence of composite support in Mn-based catalysts on LT SCR activity and sulfur resistance.

Background: It remains unclear whether or not a positive family history of affective disorders predicts the effectiveness of antidepressant treatment of depression., Aims: Assess the relationship of a family history of affective disorders to the efficacy of duloxetine in the treatment of depressive disorder., Methods: Seventy-seven patients with depressive disorder (as defined by the 10th edition of the International Classification of Diseases, ICD-10) were enrolled in the study and treated with standard doses of duloxetine for 12 weeks. Among these patients 37 had a family history of affective disorder in first-degree relatives and 40 did not. The Hamilton Depression rating scale (HAMD-17), Hamilton Anxiety rating scale (HAMA), Side Effects Rating Scale (SERS), Snaith-Hamilton Pleasure Scale (SHAPS), and Beck Depression Inventory (BDI) were assessed at baseline and at the end of the 2(nd), 4(th), 6(th), 8(th), and 12(th) week after enrollment. Repeated measures analysis of variance and logistic regression were used to analyze the association between a family history of affective disorders and the efficacy of duloxetine., Results: Patients with a positive family history of affective disorders had an earlier age of onset, a longer duration of illness, a higher level of psychic anxiety, and more prominent anhedonia. Repeated measures analysis of variance showed a significant improvement in the severity of depression over the 12 weeks but no differences in the magnitude or speed of improvement between the two groups. Treatment was considered effective (i.e., drop in baseline HAMD-17 total score of ≥50%) in 75.7% of those with a family history of affective disorders and in 77.5% of those without a family history (X(2)=0.04, p=0.850)., Conclusions: Family history of affective disorders is not associated with the effectiveness of duloxetine in the acute treatment of depressive disorder.