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Removal of VOCs from gas streams with double perovskite-type catalysts

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Journal of Environmental Sciences 2018年第7期30卷 205-216页

作者： Kuan Lun Pan Guan Ting Pan Siewhui Chong moo been chang Graduate Institute of Environmental Engineering National Central University Department of Chemical Engineering National Taipei University of Technology Department of Chemical and Environmental Engineering University of Nottingham Malaysia Campus

Double perovskite-type catalysts including La2 CoMnO6 and La2 CuMnO6 are first evaluated for the effectiveness in removing volatile organic compounds（VOCs）, and single perovskites（La CoO3, LaMnO3, and La Cu O3） are also tested for comparison. All perovskites are tested with the gas hourly space velocity（GHSV） of 30,000 hr^-1, and the temperature range of100–600℃ for C7H8 removal. Experimental results indicate that double perovskites have better activity if compared with single perovskites. Especially, toluene（C7H8） can be completely oxidized to CO2 at 300℃ as La2 Co MnO6 is applied. Characterization of catalysts indicates that double perovskites own unique surface properties and are of higher amounts of lattice oxygen,leading to higher activity. Additionally, apparent activation energy of 68 k J/mol is calculated using Mars-van Krevelen model for C7 H8 oxidation with La2 Co Mn O6 as catalyst. For durability test, both La2 Co Mn O6 and La2 CuMnO6 maintain high C7 H8 removal efficiencies of 100% and98%, respectively, at 300℃ and 30,000 hr^-1, and they also show good resistance to CO2（5%） and H2 O（g）（5%） of the gas streams tested. For various VOCs including isopropyl alcohol（C3H8 O）,ethanal（C2H4O）, and ethylene（C2H4） tested, as high as 100% efficiency could be achieved with double perovskite-type catalysts operated at 300–350℃, indicating that double perovskites are promising catalysts for VOCs removal.

关键词： Volatile organic compounds(VOCs) Toluene(C7H8) Double perovskite-type catalyst Catalysis Activation energy

Removal of formaldehyde over Mn_xCe_(1- x)O_2 catalysts: Thermal catalytic oxidation versus ozone catalytic oxidation

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Journal of Environmental Sciences 2014年第12期26卷 2546-2553页

作者： Jia Wei Li Kuan Lun Pan Sheng Jen Yu Shaw Yi Yan moo been chang Graduate Institute of Environmental Engineering National Central University Industrial Technology Research Institute

MnxCe1- xO2（x： 0.3–0.9） prepared by Pechini method was used as a catalyst for the thermal catalytic oxidation of formaldehyde（HCHO）. At x = 0.3 and 0.5, most of the manganese was incorporated in the fluorite structure of Ce O2 to form a solid solution. The catalytic activity was best at x = 0.5, at which the temperature of 100% removal rate is the lowest（270°C）. The temperature for 100% removal of HCHO oxidation is reduced by approximately 40°C by loading 5 wt.% Cu Oxinto Mn0.5Ce0.5O2. With ozone catalytic oxidation, HCHO（61 ppm） in gas stream was completely oxidized by adding 506 ppm O3 over Mn0.5Ce0.5O2 catalyst with a GHSV（gas hourly space velocity） of 10,000 hr-1at 25°C. The effect of the molar ratio of O3 to HCHO was also investigated. As O3/HCHO ratio was increased from 3 to 8, the removal efficiency of HCHO was increased from 83.3% to 100%. With O3/HCHO ratio of 8, the mineralization efficiency of HCHO to CO2 was 86.1%. At 25°C, the p-type oxide semiconductor（Mn0.5Ce0.5O2） exhibited an excellent ozone decomposition efficiency of 99.2%,which significantly exceeded that of n-type oxide semiconductors such as Ti O2, which had a low ozone decomposition efficiency（9.81%）. At a GHSV of 10,000 hr-1, [O3]/[HCHO] = 3 and temperature of 25°C, a high HCHO removal efficiency（≥ 81.2%） was maintained throughout the durability test of 80 hr, indicating the long-term stability of the catalyst for HCHO removal.

关键词： Formaldehyde Volatile organic compounds Indoor air pollutant Thermal catalytic oxidation Ozone catalytic oxidation

Photocatalytic conversion of CO2 and CH4 into syngas

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Photocatalytic conversion of CO2 and CH4 into syngas

Evaluation of Atmospheric PCDD/F Depositions via Automated and Traditional Water Surface Samplers in Taiwan

第十五届海峡两岸气胶技术研讨会

作者： Wei Chieh Chung Yun En Li moo been chang Graduate Institute of Environmental Engineering "Central University"

Human activities including fossil fuel combustion,agriculture and husbandry lead to increasing anthropogenic emission of greenhouse gases(GHGs).Emission of GHGs including CO and CH has resulted in global warming and climate *** a result,effective reduction of CO and CH emissions is an urgent issue in 21 st *** dioxide utilization can be a candidate to effectively reduce CO emission and reforming of CO/CH-4 mixture stands for a potential carbon dioxide utilization technique and possesses capability to generate the energy carrier,syngas(mixture of H/CO).Among several reforming techniques,photocatalytic conversion of CO/CH is a promising approach since the driving force of the system is solar energy,the most abundant energy and the advantage of easy ***-type photocatalyst has the advantages of high resistivity toward photocorrosion and easy *** this study,perovskite-type photocatalyst(La eO) is prepared to convert CO/CH mixture into syngas with an irradiance of Xenon *** show that the self-prepared photocatalyst has a bandgap of 2.06 eV and can absorb visible light during ***,our photocatalysis system can effectively convert CO/CH into syngas and the conversion rate increase with increasing irradiance as shown in Figure *** information and relevant mechanisms will be presented and elucidated in this paper.

关键词： greenhouse gases reforming of CO2 photocatalysis Themes Alternative studies related to aerosol greenhouse gas and air

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Evaluation of Atmospheric PCDD/F Depositions via Automated a...

Destruction and removal efficiency of PICs by various iron ores during sintering-exploratory testing

第九届海峡两岸气溶胶技术研讨会暨第二届海峡两岸环境保护双门论坛

作者： Kai Hsien Chi Shuh Ji Kao Shu Hao chang moo been chang Institute of Environmental and Occupational Health Sciences Taiwan Yang Ming University Research Center for Environmental changes Academia Sinica Graduate Institute of Environmental Engineering Taiwan Central University

Polychlorinated dibenzo-p-dioxins and dibenzofurans(PCDD/Fs)are a group of compounds of major environmental *** emitted into the atmosphere,PCDD/Fs undergo photochemical reactions and enter other environmental compartments via wet and dry *** this study,atmospheric PCDD/F depositions were collected via an automated PCDD/F deposition sampler and traditional cylindrical vessels,respectively,in northern,central and southern Taiwan from 2008 to *** automated PCDD/F precipitation sampler used in this study can prevent both re-suspension and photodegradation of the PCDD/Fs collected and also effectively separates the PCDD/F samples into dry and wet *** results indicate that the average atmospheric PCDD/F concentrations collected by the high-volume sampling trains were:13.6±10(n=10),15.6+5.2(n=7)and 10.9+6.3(n=6)fg I-TEQ/m in northern,central and southern Taiwan,*** addition,the results also indicate that the PCDD/F deposition flux collected with an automated PCDD/F sampler(1.84±0.90.68±5.1 pg I-TEQ/m/day,n=23)is significantly higher than that sampled with cylindrical vessels(1.11±0.69.64±5.2 pg I-TEQ/m/day,n=23).Based on the Mann-Whitney statistical analysis,the p value(0.037)of PCDD/F deposition flux between those two samplers measurement is lower than *** difference is attributed to the fact that part of the PCDD/F depositions collected by traditional cylindrical vessels is photo degraded and re-volatilization.

关键词： Dioxins deposition water surface sampler aerosol

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Baosteel Technical Research 2010年第S1期4卷 131-页

作者： Alfons Georges BUEKENS Joeri DENAYER Guy REGGERS Robert CARLEER Damien DEBECKER moo been chang Zhejiang University Hangzhou China Vrije Universiteit Brussel VUB BrusselsBelgium Universiteit Hasselt Diepenbeek Belgium Universite catholique de Louvain UCL Louvain-la-Neuve Belgium NATIONAL CENTRAL UNIVERSITY C HUNGLITAIWAN

Worldwide,iron ore sintering is the largest industrial single source of dioxin emissions^(1-3).Conversely, some ores may help in reducing emissions,because of their aptitude of(a) adsorbing and(b) oxidising or decomposing TOC and dioxins^(4,5).Such dioxin abatement abilities were tested for five types of ores,representing major ore origins(Australia,Brazil,and South Africa ),minerals(magnetite,haematite,goethite,pisolite ),and properties,***,and Loss on Ignition(LOI) *** total,11 exploratory experimental runs were conducted on iron ores,to test the oxidation in air of four different organic trace test substances:acetone, chloroform,n-hexane,and toluene contained in a test gas were led simultaneously over the ore over a preestablished temperature *** test comprehends a first part with a programmed temperature rise,a brief soaking period at the temperature maximum(>400℃),and a ballistic cooling *** concentration of the four organics is continuously monitored by Mass Spectrometry(MS) operating in a full-scan mode(m/e < 100). Exploratory experiments allowed differentiating the ores tested according to the Destruction & Removal Efficiency(DRE) *** check the results the products of oxidation in the effluent were sampled on Tenax and ***,the dioxin load remaining on several test residues was examined and found to be quite limited (pg I-TEQ/g).

关键词： acetone catalytic oxidation chloroform dioxins goethite haematite iron ore magnetite mass spectrometry n-hexane,pisolite sintering,sorption Tenax,toluene

Data-based neural controls for an unknown continuous-time multi-input system with integral reinforcement

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Control Theory and Technology 2025年第1期23卷 118-130页

作者： Yongfeng Lv Jun Zhao Wan Zhang Huimin chang College of Electrical and Power Engineering Taiyuan University of TechnologyTaiyuanShanxi030024China College of Transportation Shandong University of Science and TechnologyQingdao266590ShandongChina School of Mathematical Sciences Shanxi UniversityTaiyuan030006ShanxiChina

Integral reinforcement learning(IRL)is an effective tool for solving optimal control problems of nonlinear systems,and it has been widely utilized in optimal controller design for solving discrete-time ***,solving the Hamilton-Jacobi-Bellman(HJB)equations for nonlinear systems requires precise and complicated ***,the research and application of IRL in continuous-time(CT)systems must be further *** develop the IRL of a CT nonlinear system,a data-based adaptive neural dynamic programming(ANDP)method is proposed to investigate the optimal control problem of uncertain CT multi-input systems such that the knowledge of the dynamics in the HJB equation is ***,the multi-input model is approximated using a neural network(NN),which can be utilized to design an integral reinforcement ***,two criterion networks and one action network are constructed based on the integral reinforcement signal.A nonzero-sum Nash equilibrium can be reached by learning the optimal strategies of the multi-input *** this scheme,the NN weights are constantly updated using an adaptive *** weight convergence and the system stability are analyzed in *** optimal control problem of a multi-input nonlinear CT system is effectively solved using the ANDP scheme,and the results are verified by a simulation study.

关键词： Adaptive dynamic programming Integral reinforcement Neural networks Heuristic dynamic programming Multi-input system

Long-duration aqueous Zn-ion batteries achieved by dual-salt highly-concentrated electrolyte with low water activity

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Journal of Energy Chemistry 2025年第2期101卷 778-785页

作者： Lvzhang Jiang Lingbo Yao Gege Wang chang Liu Xiaowei Chi Yu Liu Shanghai Institute of Ceramics Chinese Academy of Sciences University of Chinese Academy of Sciences

Aqueous Zn-ion batteries have attracted much attention due to their unique high safety and low-cost ***,their practical applications are at a slow pace due to their short cycle life,which fundamentally results from the instability of the positive/negative electrode interface in the traditional dilute aqueous electrolytes with high water *** highly concentrated electrolyte（HCE）has been considered as an effective *** previous studies of single salt-based HCE（SSHCE）,herein,a new dual-salt HCE（15 m ZnCl2+10 m NH4NH2SO3DS-HCE） was proposed for the first ***-HCE was proven to simultaneously possess higher conductivity than traditional dilute electrolytes and ultralow water activity of SS-HCE by the regulation of dual high-concentration salts on the solvation structure,which renders the Zn‖Zn symmetric cell the record-long cycling life of 2200 h compared with those with SS-HCE（30 m ZnCl2,300 h） and other reported ***,the Zn‖NH4V4O10full cell with DS-HCE demonstrated impressed rate capability within a wide-range current densities from 0.1 to 10 A ***,at the high current density of 5 A g-1,the full cell shows almost100% capacity retention after 4000 cycles,which indicates the promising future of the DS-HCE system for long-duration aqueous Zn-ion batteries.

关键词： Ammonium vanadate Aqueous zinc battery Cycling stability Electrolyte

Status analysis on sputtering and erosion evaluation methods of ion optic systems

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Chinese Journal of Aeronautics 2025年第1期38卷 254-270页

作者： Long MIAO Tongxun YANG Zhengxi ZHU chang LU Zhiwen WU Ningfei WANG School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Chongqing Innovation Center Beijing Institute of TechnologyChongqing 404100China Advanced Aerospace Power and Energy Research Center Beijing Institute of TechnologyZhuhai 519088China

In the past few decades,ion engines have been widely used in deep-space propulsion and satellite *** aim of extending the thruster lifetime is still one of the most important parts during the design stage of ion *** one of the core components of ion engine,the grid assembly of ion optic systems may experience long-term ion sputtering in extreme electro-thermal environments,which will eventually lead to its structural and electron-backstreaming *** this paper,the current studies of the grid assembly erosion process are systematically analyzed from the aspects of sputtering damage process of grid materials,numerical simulations,and measurements of erosion characteristics of grid *** advantages and disadvantages of various erosion prediction models are highlighted,and the key factors and processes affecting the prediction accuracy of grid assembly erosion patterns are *** different types of experimental methods of grid assembly erosion patterns are *** analysis in this paper is of great importance for selecting the sputter-resistant grid materials,as well as establishing the erosion models and measurement methods to accurately determine the erosion rate and failure modes of grid ***,the working conditions and structure parameters of ion optic systems could be optimized based on erosion models to promote the ion engine lifetime.

关键词： Electric propulsion Ion optic systems Sputtering yield Erosion characteristics Erosion pattern measurement Lifetime evaluation

Spatiotemporal evolution of Ediacaran-Cambrian(ca.551–523 Ma)sponges in South China and their simulated contributions to marine oxygenation

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Science China Earth Sciences 2025年第2期68卷 549-563页

作者： Yan YE Lei ZHANG Can CHEN Shan chang Yuhao YI Qinglai FENG State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430074China School of Earth Science China University of GeosciencesWuhan 430074China Department of Geology Lund UniversityLund 22362Sweden Institute of Sedimentary Geology Chengdu University of TechnologyChengdu 610059China Key Laboratory of Deep-time Geography and Environment Reconstruction and Applications of Ministry of Natural Resources Chengdu University of TechnologyChengdu 610059China Second Geological Brigade of Hubei Geological Bureau Enshi 445000China College of Urban and Environmental Sciences Hubei Normal UniversityHuangshi 435002China Exploration and Development Research Institute SINOPEC Jianghan Oilfield CompanyWuhan 430223China

The origin and evolution of sponges have attracted interest,not only because they are among the most basal metazoans,but also because they act as important ecological engineers in the *** research suggested that sponge groups diversified quickly during the Cambrian Series 2,while Terreneuvian sponge fossils are conspicuously rare and poorly ***,an increasing number of sponge spicules have been reported from the Ediacaran-Cambrian(E-C,ca.551–523 Ma)transitional carbonates/cherts worldwide,particularly in South China,which calls for updated *** oxygenation has been widely proposed to play a critical role in organismal evolution,but its relationship with sponges is unclear and falls into a“chicken-egg”*** this study,we summarize reported sponge spicule distributions from five E-C sections in South China to investigate the early evolutionary pattern of siliceous *** to current stratigraphic correlation,monaxons first appear in the late Ediacaran in the intrashelf basin-slope area,and then potentially expand to the continental shelf and deep basin in the lower *** these sections,the abundance,size,and diversity of monaxons increase upwards,followed by the appearance of diaxons,triaxons and then *** the uncertain affinity of the sponge fossils,it is possible that siliceous hexactinellids evolved later than siliceous demosponges,given that the earliest spicule assemblages are exclusively composed of monaxons,which commonly form bundles comparable to modern *** geochemical data from the Sifangjing section,Guizhou Province and the Yanziqiao section,Hunan Province,South China show that the appearance of sponges usually corresponds to anoxic *** addition,we applied the recently proposed Biological Pump,Oxygen and Phosphorus(BPOP)model to trace the evolution of oceanic oxygen concentrations with the radiation of *** results indicate that the possible contribution o

关键词： Cambrian Sponge Oxygenation Silicon concentration Box model

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