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Ethyl and butyl acetate oxidation over manganese oxides 被引量:2
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作者 Olívia Salomé G.P.Soares Raquel P.Rocha +2 位作者 Jose J.M.Orfao Manuel F.R.Pereira José L.Figueiredo 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第1期27-36,共10页
Mangenese oxides were synthesized using two new methods,a novel solvent‐free reaction and a reflux technique,that produced cryptomelane‐type products(K‐OMS‐2).Oxides were also synthesized using conventional method... Mangenese oxides were synthesized using two new methods,a novel solvent‐free reaction and a reflux technique,that produced cryptomelane‐type products(K‐OMS‐2).Oxides were also synthesized using conventional methods and all specimens were applied to the oxidation of ethyl acetate and butyl acetate,acting as models for the volatile organic compounds found in industrial emissions.The catalysts were also characterized using N2adsorption,X‐ray diffraction,scanning electron microscopy,temperature programmed reduction and X‐ray photoelectron spectroscopy.Each of the manganese oxides was found to be very active during the oxidation of both esters to CO2,and the synthesis methodology evidently had a significant impact on catalytic performance.The K‐OMS‐2nanorods synthesized by the solvent‐free method showed higher activity than K‐OMS‐2materials prepared by the reflux technique,and samples with cryptomelane were more active than those prepared by the conventional methods.The catalyst with the highest performance also exhibited good stability and allowed90%conversion of ethyl and butyl acetate to CO2at213and202°C,respectively.Significant differences in the catalyst performance were observed,clearly indicating that K‐OMS‐2nanorods prepared by the solvent‐free reaction were better catalysts for the selected VOC oxidations than the mixtures of manganese oxides traditionally obtained with conventional synthesis methods.The superior performance of the K‐OMS‐2catalysts might be related to the increased average oxidation state of the manganese in these structures.Significant correlations between the catalytic performance and the surface chemical properties were also identified,hig-hlighting the K‐OMS‐2properties associated with the enhanced catalytic performance of the materials.?2018,Dalian Institute of Chemical Physics,Chinese Academy of Sciences.Published by Elsevier B.V.All rights reserved. 展开更多
关键词 Volatile organic compound Ethyl acetate Butyl acetate Manganese oxide Catalytic oxidation
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A novel S-scheme 3D ZnIn_(2)S_(4)/WO_(3) heterostructure for improved hydrogen production under visible light irradiation 被引量:4
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作者 Mengyu Zhao Sen Liu +3 位作者 Daimei Chen Sushu Zhang Sónia A.C.Carabineiro Kangle Lv 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第10期2615-2624,共10页
In-plane epitaxial growth of ZnIn_(2)S_(4) nanosheets on the surface of hexagonal phase WO_(3) nanorods was achieved by a facile solvothermal method.The unique 3D heterostructure not only enlarged the specific surface... In-plane epitaxial growth of ZnIn_(2)S_(4) nanosheets on the surface of hexagonal phase WO_(3) nanorods was achieved by a facile solvothermal method.The unique 3D heterostructure not only enlarged the specific surface area,but also red-shifted the absorption edge from 381 to 476 nm to improve the light harvesting ability,which largely enhanced the photocatalytic hydrogen evolution.The H_(2) production rate of the best performing ZnIn_(2)S_(4)/WO_(3) photocatalyst(ZIS-2.5/W,the material with a molar rate of ZnIn_(2)S_(4)(ZIS)to WO_(3)(W)of 2.5)was 300μmol·g^(–1)·h^(–1),around 417 times and 2 times higher than the rates of pristine WO_(3) and ZnIn_(2)S_(4),respectively.The apparent quantum efficiency for ZIS-2.5/W composite was up to 2.81%at 400 nm.Based on the difference in Fermi levels between WO_(3) and ZnIn_(2)S_(4),and the distribution of the redox active sites on WO_(3)/ZnIn_(2)S_(4) heterostructure,a S-scheme electron transfer mechanism was proposed to illustrate the improved photocatalytic activity of WO_(3)/ZnIn_(2)S_(4) heterojunction,which not only stimulated the spatial separation of the photogenerated charge carriers,but also maintained the strong reduction/oxidation ability of the photocatalyst. 展开更多
关键词 WO_(3) ZnIn_(2)S_(4) PHOTOCATALYSIS S-Scheme Hydrogen evolution
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Antidepressant-like Effects of Ginsenoside Rg1 in the Chronic Restraint Stress-induced Rat Model 被引量:8
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作者 JIANG Ning LV Jing-Wei +6 位作者 WANG Hai-Xia HUANG Hong WANG Qiong CHEN Shan-Guang QU Li-Na Alberto Carlos Pires Dias LIU Xin-Min 《Digital Chinese Medicine》 2019年第4期207-218,共12页
Objective To investigate the ameliorating effect of ginsenoside Rg1 on the depression-like behaviors induced by chronic restraint stress(CRS)in rats and the underlying mechanisms.Methods Forty male Wistar rats were di... Objective To investigate the ameliorating effect of ginsenoside Rg1 on the depression-like behaviors induced by chronic restraint stress(CRS)in rats and the underlying mechanisms.Methods Forty male Wistar rats were divided into 4 groups according to their baseline sucrose preference:control group,model group,and Rg1-treated groups(5 and 10 mg/kg).Except for control group,the groups were exposed to CRS(6 h/day)for 28 days.All drugs were intraperitoneally administered once daily to CRS rats after restraint stress for 14 days.The behavioral tests were carried out via the open field test(OFT),sucrose preference test(SPT),forced swim test(FST),and the Morris water maze(MWM)4 weeks following CRS induction.The levels of serum corticosterone(CORT)and the activities of the antioxidant defense biomarkers(SOD,MDA and GSH-x)in the prefrontal cortex(PFC)were analyzed using commercial ELISA kits.The levels of the neurotransmitter(5-HT,5-HIAA,Ach,NE,GABA and Glu)in the PFC were measured by ultra-performance liquid chromatography tandem mass spectrometry.The protein expression of BDNF,Trkb,Bax and Bcl-2 in the PFC was detected by western blotting.Results Owing to increased sucrose consumption in the SPT,decreased immobility time in the FST,and the improved cognitive performance in MWM,chronic treatment with Ginsenoside Rg1 was found to significantly attenuate depressionlike behaviors(anhedonia,behavioral despair and poor spatial memory)in rats.Moreover,CRS exposure caused evident alterations in the levels of the neurotransmitters(5-HT,5-HIAA,Ach,GABA and Glu)and the activities of the antioxidant defense biomarkers(SOD,MDA and GSH-x)in the PFC and the levels of corticosterone in serum.However,Ginsenoside Rg1 treatment could restore these levels to normal values.Additionally,Ginsenoside Rg1 treatment significantly reverted the decreased expression of BDNF,Trkb and Bcl-2 and the increased expression of Bax in the PFC of CRS rats.Conclusions Ginsenoside Rg1 could attenuate the CRS-induced depression-like behaviors,in part,by regulating neurotransmitter levels and HPA function,antagonizing oxidative stress and apoptosis,and restoring BDNF-TrkB signaling in PFC.Altogether,our results provide a novel basis regarding the potential therapeutic effects of Rg1 on depression. 展开更多
关键词 Ginsenosides Rg1 DEPRESSION Chronic restraint stress NEUROTRANSMITTER Oxidative stress BDNF
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矿产资源与矿石储量估算和报表的实际状况(一)
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作者 R.A.奥拉姆 林参 肖远秀 《国外金属矿山》 2002年第5期10-15,共6页
矿产资源与矿石储量估算、矿山规划、矿山测量、工厂作业以及生产结果与原先期望值的调整等工作 ,在矿山生产中是持续不断的作业过程。这些活动在延续很长的整个周期内包含了若干不同的学科部门。尽管生产条件、政策和人员可能会有变动 ... 矿产资源与矿石储量估算、矿山规划、矿山测量、工厂作业以及生产结果与原先期望值的调整等工作 ,在矿山生产中是持续不断的作业过程。这些活动在延续很长的整个周期内包含了若干不同的学科部门。尽管生产条件、政策和人员可能会有变动 ,都必须持续不断地进行估算和报道 ,以便在周期性的评估和调整中做到准确可靠。生产实践被认为是与采矿和管理机构致力于“资源”与“储量”定义改进的背景条件相适应的。文中的实例是关于地下金矿开采的 ,但其原则也可适用于其他环境。该系统的许多基本要点已在生产的某些适当位置中加以叙述 ,但可能不会始终如一地被采用。在其他一些矿山 ,可能会在某种特定的基础上对该系统作了修改 ,其结果是并非每个人都能理解它们 ,或者是某些人可能会对数据产生误解。当业主或关键的雇员出现变动时 ,或者是当第三方对资源、储量和生产数据的陈述持有不一致的解释时 (如 ,在确证研究中 ) ,就可能会有严重的后果文中对资源与储量估算效能的监测和发展趋势的有效报道进行了讨论。指出了可适用于大多数环境的某些术语和系数的定义 ,并建议把“验证的矿产资源估算”作为一种内部工具 ,用来在采矿工作开始以前 ,即时地提供最终的矿产资源检验。文中强调了务实的开采计划和回采与开拓物? 展开更多
关键词 矿产资源 储量估算 矿石储量 采矿
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