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The RuO2@CemZr1−mO2−SiO2 catalysts were synthesized by the spontaneous deposition method. Based on the XRD patterns of various RuO2@CemZr1−mO2−SiO2 catalysts, it was suggested that the Ru noble metal nanoparticles were distributed with high dispersion on the surface of Ce‐modified porous matrix of ZrO2. H2‐TPR and NH3‐TPD confirmed that all catalysts possessed superior redox ability as well as acidity, which were facilitated to the catalytic dichloroethane (DCE) oxidation. From the systematic study of texture structure, surface properties and catalytic activity, we knew that acid sites were shown to be favorable for adsorption as well as activation of DCE and improve the anti‐poisoning property of the catalyst, and the redox ability could facilitate the further oxidation of the intermediate. The optimized RuO2@Ce0.1Zr0.9O2−SiO2 catalyst exhibited superior activity (T90=275 °C at a space velocity of 15000 h−1), good stability (at 300 °C for 50 h) and outstanding tolerance towards moisture (in 5 % moisture). Our work demonstrated the important role of acidity and redox ability over these functionalized catalysts, providing guidance for the advanced catalyst design. [ABSTRACT FROM AUTHOR]

Adjusting the acidity and/or oxygen species on the surface of metal oxide nanostructures could fabricate the high active and durable catalysts for the combustion of chlorinated volatile organic compounds (CVOCs). Herein, Al‐modified mesoporous SiO2 matrix supported uniform CeO2 nanodots (CeO2@xAlSiO2) was synthesized and evaluated in dichloroethane (DCE) catalytic combustion. From the systematic study of the texture structure, surface properties, and catalytic activity, we deduced that the improved surface acidity and oxygen species activity enhanced the DCE conversion and reduced the formation of chlorinated organic byproduct, while increasing the formation of the desired product, HCl. The optimized CeO2@0.5AlSiO2 sample showed superior activity (90 % conversion of DCE at 260 °C), excellent durability (at 280 °C for 60 h) and good tolerance towards moisture (in 1 % and 3 % moisture for 10 h, respectively). Our work identified the important role of surface acidity and oxygen species over these functionalized catalysts, providing guidance for the advanced catalyst design. [ABSTRACT FROM AUTHOR]

A side‐reactor column (SRC) configuration, which integrates vacuum distillation with atmospheric reaction, was developed for dimethyl adipate (DMA) production. The sequential optimization method was applied to optimize the design parameters including side stream drawn stage, reactor numbers, and catalyst loading with total annual cost (TAC) as objective function in order to realize the economical design. The best economic performance was achieved as the result of the specific SRC configuration featuring one column with 20 stages where DMA was drawn from the 5th stage and one side‐reactor was equipped in the bottom. Moreover, a proportion‐temperature cascade control structure was successfully developed which avoids the disturbance of inlet flow rate and composition. [ABSTRACT FROM AUTHOR]

Central sensitization is the potential pathogenesis of chronic migraine (CM) and is related to persistent neuronal hyperexcitability. Dysfunction of excitatory amino acid transporter 2 (EAAT2) leads to the accumulation of glutamate in the synaptic cleft, which may contribute to central sensitization by overactivating glutamate N‐methyl‐D‐aspartate receptors and enhancing synaptic plasticity. However, the therapeutic potential of CM by targeting glutamate clearance remains largely unexplored. The purpose of this study was to investigate the role of EAAT2 in CM central sensitization and explore the effect of EAAT2 expression enhancer LDN‐212320 in CM rats. The glutamate concentration was measured by high‐performance liquid chromatography in a rat model of CM. Then, q‐PCR and western blots were performed to detect EAAT2 expression, and the immunoreactivity of astrocytes was detected by immunofluorescence staining. To understand the effect of EAAT2 on central sensitization of CM, mechanical and thermal hyperalgesia and central sensitization‐associated proteins were examined after administration of LDN‐212320. In addition, the expression of synaptic‐associated proteins was examined and Golgi‐Cox staining was used to observe the dendritic spine density of trigeminal nucleus caudalis neurons. Also, the synaptic ultrastructure was observed by transmission electron microscope (TEM) to explore the changes of synaptic plasticity. In our study, elevated glutamate concentration and decreased EAAT2 expression were found in the trigeminal nucleus caudalis of CM rats, administration of LDN‐212320 greatly up‐regulated the protein expression of EAAT2, alleviated hyperalgesia, decreased the concentration of glutamate and the activation of astrocytes. Furthermore, reductions in calcitonin gene‐related peptide, substance P(SP), and phosphorylated NR2B were examined after administration of LDN‐212320. Moreover evaluation of the synaptic structure, synaptic plasticity‐, and central sensitization‐related proteins indicated that EAAT2 might participate in the CM central sensitization process by regulating synaptic plasticity. Taken together, up‐regulation of EAAT2 expression has a protective effect in CM rats, and LDN‐212320 may have clinical therapeutic potential. Cover Image for this issue: https://doi.org/10.1111/jnc.14769. [ABSTRACT FROM AUTHOR]

Ceria (CeO2) has been regarded as one of the most promising industrial catalysts for hydrochloric acid (HCl) oxidation to replace RuO2‐based catalysts. Thermal sintering and chlorination of CeO2 limit its large‐scale application. In this work, ultrafine CeO2 nanodots embedded in a porous ZrO2 matrix (CeO2@ZrO2) are successfully prepared by a spontaneous deposition method and evaluated in HCl catalytic oxidation for sustainable Cl2 recycle. The physicochemical properties of CeO2@ZrO2 catalysts are characterized by means of XRD, Raman, SEM, TEM, BET, XPS, H2‐TPR and oxygen storage capacity (OSC). The results reveal that all CeO2@ZrO2 catalysts display large specific surface area, pore volume, perfect low‐temperature reduction performance and oxygen storage‐release capacity. More importantly, the unique structure of the CeO2 nanodots isolated by amorphous ZrO2 improves the dispersion and inhibits the sintering of active sites. The optimized 40CeO2@ZrO2 catalyst reveals superior activity (1.90 gCl2 ⋅ gcat−1 ⋅ h−1) and good durability (100 h under 430 °C). Kinetic studies reveal that the adsorption of O2 and HCl is competitive at the active sites, and the desorption of surface Cl is the rate‐determining step. [ABSTRACT FROM AUTHOR]

In this study, highly‐dispersed perovskite‐type oxides LaMnxCo1‐xO3 supported on mesoporous SiO2 (LMxC1‐xO/SiO2) were synthesized by a citric acid‐assisted deposition method. For LMxC1‐xO/SiO2 catalysts, the double B‐site transition metal ions can not only significantly arise the surface defects, but also lead to the formation of (Mn3++Co3+)/(Co2++Mn4+) redox cycle, both of which were able to improve the catalytic performance of LMxC1‐xO/SiO2 in n‐butylamine combustion. Strikingly, LM0.2C0.8O/SiO2 catalyst showed the optimum catalytic performance (T90%=210 °C at a space velocity of 15,000 mL gcat−1 h−1) and the lowest NOx yield among the LMxC1‐xO/SiO2 samples, which could be greatly assigned to the accelerated activation and circulation of the oxygen species initiated by the surface defects and redox cycle. [ABSTRACT FROM AUTHOR]

Abstract: In order to investigate the effect of the pore and surface properties of carbon aerogels on carbon dioxide adsorption, carbon aerogels were synthesized at different calcination temperatures. The adsorbents were characterized by various technologies, such as X‐ray diffraction, Raman, N2 sorption, and Fourier transform infrared technologies. It was found that the adsorption sites for CO2 caused by pore and surface of the adsorbent determined the CO2 adsorption abilities. The CA‐800 sample carbonized at 800 °C showed the excellent CO2 adsorption capacity (93.98 cm3⋅g−1 at 0 °C) because of the largest pore volume (1.55 cm3⋅g−1) and the highest relative microporous volume determined by the ratio of microporous volume and total volume (0.31/1.55). The richness of the surface functional groups of the carbon aerogels declined and the surface defects determined by the intensity ratio of D and G bands (ID/IG) increased from 0.7584 (CA‐600) to 1.1029 (CA‐900) gradually as the carbonization temperature increasing. It was used to predict the relationship between the CO2 adsorption capacity and the structure properties by the means of equation fitting. The result showed that the highest ratio of Vmicro/Vtol and the lowest surface defects were crucial to the CO2 adsorption performance. A serials of carbon aerogels were synthesized at different calcination temperatures to investigate the effect of the pore and surface properties of carbon aerogels on carbon dioxide adsorption. It was found that high ratio of Vmicro/Vtol and low surface defects for carbon aerogels were crucial to the CO2 adsorption performance, which may provide a new approach to enhance CO2 performance for carbon aerogels. [ABSTRACT FROM AUTHOR]

A series of carbon aerogels were synthesized by polycondensation of resorcinol and formaldehyde using cetyltrimethyl ammonium bromide (CTAB) as a catalyst. The structure and properties of carbon aerogels were characterized by X-ray diffraction (XRD), Raman, scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FT-IR), and N2 adsorption-desorption technologies. Besides, the CO2 capture behavior of carbon aerogels was also investigated. It was found that the amount of CTAB affected the structure and morphology of carbon aerogels, thus influenced the CO2 adsorption behavior. The sample CA-125 (the ratio of resorcinol and CTAB is 125) had the highest CO2 adsorption capacity (63.71 cm3·g-1 at 1 bar and 24.14 cm3·g-1 at 0.15 bar) at 25 °C. In addition, the higher CO2 adsorption capacity was ascribed to the higher surface area, pore volume and appropriate pore size, as well as the more defects over carbon aerogels. [ABSTRACT FROM AUTHOR]

The development and validation of a novel kinetic model for the chlorination of 1,2-dichloroethane to ultimately hexachloroethane catalyzed by blue light are presented. A factor ( X m) related to the chlorination depth was introduced into the kinetics model, and the results showed that the dynamic features of the photo-chlorination are better predicted by the modified model than by the conventional one. Furthermore, to enhance the selectivity towards tetrachloroethane and pentachloroethane, a novel reactive distillation with side-reactor configuration (SRC) for the photo-chlorination process was proposed. In order to demonstrate the technical feasibility of the process, semi-batch SRC experiments on the laboratory scale were carried out. Up to 96.5 wt % of tetrachloroethane and pentachloroethane with molar ratios varying from 7 to 0.7 over time were obtained in the bottom product. [ABSTRACT FROM AUTHOR]

Lean-oxygen oxidation of HCl, in which O2 conversion can reach as high as ∼60 to ∼90 %, can greatly simplify the process of recycling Cl2 using gas-phase catalysis technology. The O2 consumption rate in lean-oxygen HCl oxidation over a supported CuO-CeO2 composite oxide catalyst was studied using an integral tube reactor. After eliminating the diffusion effects, three empirical kinetic models were proposed, which assumed O2 adsorption, surface reaction, and Cl2 desorption as the rate-controlling steps, respectively. Based on O2 adsorption as the rate-controlling step, the results indicate that the kinetic Model I best describes the coincidence between the predicted results and the experimental data. The results laid an essential foundation for reactor simulation, scale-up, and optimization of the industrial process. [ABSTRACT FROM AUTHOR]

The nanostructures of silica-encapsulated NiO nanoparticles (NPs) doped with La, Ce, Ba, Co, Cu, and Fe were prepared and tested as catalysts for the partial oxidation of methane to syngas. Techniques that include TEM, XRD, Brunauer-Emmett-Teller (BET), X-ray photoelectron spectroscopy (XPS), H2 temperature-programmed reduction (TPR), and O2 temperature-programmed oxidation (TPO) were employed to characterize the fresh and used catalysts to understand the structure-performance relationship. The La-doped Ni@SiO2 catalyst is superior to those doped with other elements. The effect of the reaction conditions on the catalyst performance over the best catalyst were also studied. The La2O3 species that were distributed uniformly throughout the NiO or Ni cores not only modify the core surfaces, but also enhance the resistance toward surface coking, which results in superior catalyst activity and durability. [ABSTRACT FROM AUTHOR]