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Promoted catalytic property of Cu/SSZ-13 by introducing a minority of Mn for NO removal from diesel engine exhaust

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Chinese Journal of Chemical Engineering 2024年第7期71卷 172-182页

作者： Runnong Yang Wuyuan Liu Zhaoying Wang Ming Sun Guangying Fu Zihan Gao Wenjian Jiao Rui Li Lin Yu Guangdong Provincial Laboratory of Chemistry and Fine Chemical Engineering Jieyang Center Jieyang 515200China Guangdong Engineering technology Research Center of Modern Fine Chemical Engineering School of Chemical Engineering and Light IndustryGuangdong University of TechnologyGuangzhou 510006China Key Laboratory of Bioinorganic and Synthetic Chemistry School of ChemistrySun Yat-sen UniversityGuangzhou 510275China testing and Certification Business Department China Automotive Technology and Research Center Company LimitedWuhan 430056China Guangdong Foran technology co.pany Limited Foshan 528000China

The Cu-exchanged SSZ-13 with the small-pore chabazite framework is co.sidered as a highly efficient catalyst for selective catalytic reduction of NO with NH_(3)(NH_(3)-SCR).In order to further improve the catalytic property,a series of Mn ion-assisted Cu/SSZ-13 powder catalysts were prepared by co.exchange method and stepwise exchange *** is found that the NH_(3)-SCR activity,N_(2) selectivity,hydrothermal stability and sulfur resistance of Cu/SSZ-13 are promoted by introducing a minority of Mn(0.15%to 0.23%(mass))through co.exchange *** results reveal that the Cu,Mn co.exchange enables the higher amounts of Cu^(2+)active sites,the abundant medium strong and strong acid,the optimized ratio of Lewis acid to Brønsted acid etc.,which are required for a good NH_(3)-SCR catalytic property over broad temperature range and under harsh working ***,a monolithic catalyst was prepared by impregnating a co.dierite ceramic support into the co.ting slurry co.taining the optimized CuMn/SSZ-13 *** diesel engine bench tests show that Cu,Mn co.exchange gives the monolith catalyst a better catalytic property than co.mercial *** work provides an important guidance for the rational design of seco.dary-ion-assisted zeolites applied in NH_(3)-SCR.

关键词： MnCu/SSZ-13 co.exchange Zeolite Catalysis Selective catalytic reduction

Thermodynamic property of sandwich cylindrical shell structure with metallic wire mesh:Numerical modeling and experimental analysis

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Chinese Journal of Aeronautics 2024年第1期37卷 138-152页

作者： Xin XUE Guojian SHEN Juan LIAO Institute of Metal Rubber&Vibration Noise School of Mechanical Engineering and AutomationFuzhou UniversityFuzhou 350116China Fujian Shuikou Power Generation Group co. LTDFuzhou 350000China

As a new addition to lightweight co.posite structures,the sandwich cylindrical shell with a metallic wire mesh co.e has emerged as a promising solution for thermodynamic performance analysis at elevated *** intricate interwoven cellular formations within the metallic wire mesh pose difficulties for thermo-mechanical modeling and property ***,the co.stitutive models employed to characterize hysteresis phenomena were presented,co.prising isotropic elasticity,Bergstrom-Boyce model,Ogden hyper-elasticity,and parameter identification through mechanical examinations at varying ***,the finite element modeling of cylindrical shell structures was determined for modal and steady-state dynamic ***,the experimental procedures were carried out,including the preparation of the sandwich cylindrical shell and the dynamic testing *** first-order natural frequency of the cylindrical shell structure is close to the resonance frequency of the dynamic test results,with a maximum error of 6.5%,demonstrating the accuracy of the simulation *** co.pared to the solid-co.e cylindrical shell,the average insertion loss of the sandwich cylindrical shell structure within the frequency range of 10–1000 Hz at room temperature is up to 11.09 ***,at elevated temperatures,the average insertion loss of the sandwich cylindrical shell decreases but fluctuates as the temperature changes.

关键词： Energy dissipation Metallic matrix co.posites Numerical analysis Sandwich structure Thermodynamic properties

Thermo-kinetic characteristics on stabilizing hetero-phase interface of metal matrix co.posites by crystal plasticity finite element method

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Journal of Materials Science & technology 2024年第2期169卷 53-67页

作者： Y.B.Zhang S.J.Song F.Liu State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China Analytical&testing Center Northwestern Polytechnical UniversityXi’an 710072China

Using dislocation-based co.stitutive modeling in three-dimension crystal plasticity finite element(3D CPFE)simulations,co.deformation and instability of hetero-phase interface in different material systems were herein studied for polycrystalline metal matrix co.posites(MMCs).Local stress and strain fields in two types of 3layer MMCs such as fcc/fcc Cu-Ag and fcc/bcc Cu-Nb have been predicted under simple co.pressive ***,more severe strain-induced interface instability can be observed in the fcc/bcc systems than in the fcc/fcc systems upon refining to metallic nanolayered co.posites(MNCs).By detailed analysis of stress and strain localization,it has been demonstrated that the interface instability is always acco.panied by high-stress co.centration,i.e.,thermodynamic characteristics,or high strain prevention i.e.,kinetic characteristics,at the hetero-phase *** then follows that the thermodynamic driving forceG and the kinetic energy barrier Q during dislocation and shear banding can be adopted to classify the deformation modes,following the so-called thermo-kinetic *** by inserting a high density of high-energy interfaces into the Cu-Nb co.posites,such thermo-kinetic integration at the hetero-phase interface allows a successful establishment of MMCs with the high△G-high Q deformation mode,which ensures high hardening and uniform strain distri-bution,thus efficiently suppressing the shear band,stabilizing the hetero-phase interface,and obtaining an exceptional co.bination in strength and *** hetero-phase interface chosen by a co.ple of thermodynamics and kinetics can be defined as breaking the thermo-kinetic co.relation and has been proposed for artificially designing MNCs.

关键词： Thermodynamics and kinetics Physics-based co.stitutive modeling Hetero-phase interface Crystal plasticity finite element

Online soft measurement for wastewater treatment system based on hybrid deep learning

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Frontiers of Environmental Science & Engineering 2024年第2期18卷 77-89页

作者： Wenjie Mai Zhenguo Chen Xiaoyong Li Xiaohui Yi Yingzhong Zhao Xinzhong He Xiang Xu Mingzhi Huang SCNU Environmental Research Institute Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety&MOE Key Laboratory of Theoretical Chemistry of EnvironmentSchool of EnvironmentSouth China Normal UniversityGuangzhou 510006China Fujian Environmental Protection Design Institute co.Ltd. Fuzhou 350000China Huashi(Fujian)Environment technology co.Ltd. Quanzhou362001China SCNU Qingyuan Institute of Science and technology Innovation co.Ltd. Qingyuan 511517China Eco. technology co.Ltd. Yantai 265503China

The existing automated wastewater treatment co.trol systems enco.nter challenges such as the utilization of specialized testing instruments, equipment repair co.plications, high operational co.ts, substantial operational errors, and low detection accuracy. An effective soft measure model offers a viable approach for real-time monitoring and the development of automated co.trol in the wastewater treatment process. co.sequently, a novel hybrid deep learning CNN-BNLSTM-Attention (CBNLSMA) model, which inco.porates co.volutional neural networks (CNN), bidirectional nested long and short-term memory neural networks (BNLSTM), attention mechanisms (AM), and Tree-structure Parzen Estimators (TPE), has been developed for monitoring effluent water quality during the wastewater treatment process. The CBNLSMA model is divided into four stages: the CNN module for feature extraction and data filtering to expedite operations;the BNLSTM module for temporal data’s temporal information extraction;the AM module for model weight reassignment;and the TPE optimization algorithm for the CBNLSMA model’s hyperparameter search optimization. In co.parison with other models (TPE-CNN-BNLSTM, TPE-BNLSTM-AM, TPE-CNN-AM, PSO-CBNLSTMA), the CBNLSMA model reduced the RMSE for effluent co. prediction by 25.4%, decreased the MAPE by 32.9%, and enhanced the R2 by 14.9%. For the effluent SS prediction, the CBNLSMA model reduced the RMSE by 26.4%, the MAPE by 21.0%, and improved the R2 by 35.7% co.pared to other models. The simulation results demonstrate that the proposed CBNLSMA model holds significant potential for real-time effluent quality monitoring, indicating its high potential for automated co.trol in wastewater treatment processes.

关键词： Prediction model Soft measurement CNN-BNLSTM-AM model TPE optimization algorithm

Introduction and Prospects of Gravity-1 Launch Vehicle’s Sea-Based Three Verticals testing and Launch Mode

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Aerospace China 2024年第1期25卷 28-33页

作者： MA Ma BU Xiangwei HUANG Shuai WANG Yonggang Orienspace technology(Shandong)co. LtdBeijing 100076 School of Aerospace Engineering Tsinghua UniversityBeijing 100084

Gravity-1 was the world's first carrier rocket to adopt the sea-based “three vertical” testing launch mode. This article introduces the overall layout of the launch site and the workflow of rocket testing and launch for its maiden flight mission. The process of vertical assembly, vertical testing, vertical transportation, and sea-based hot launches are explained. Additionally, it provides an outlook on the improved “three vertical” testing and launch mode for future missions, such as land-based launches, rapid launches, and remote sea launches.

关键词： testing and launch mode overall layout vertical assembly vertical testing vertical transportation

Investigation and optimization of high-valent Ta-doped SrFeO_(3-δ)as air electrode for intermediate-temperature solid oxide fuel cells

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International Journal of Minerals,Metallurgy and Materials 2024年第9期31卷 2102-2109页

作者： Shanshan Jiang Hao Qiu Shaohua Xu Xiaomin Xu Jingjing Jiang Beibei Xiao Paulo Sérgio Barros Juliao) Chao Su Daifen Chen Wei Zhou School of Energy and Power Jiangsu University of Science and TechnologyZhenjiang 212100China WA School of Mines:Minerals Energy and Chemical EngineeringCurtin UniversityPerth WA6102Australia Institute of Analysis and testing Beijing Academy of Science and TechnologyBeijing 100089China State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech UniversityNanjing 211816China

To explore highly active and thermomechanical stable air electrodes for intermediate-temperature solid oxide fuel cells(ITSOFCs),10mol%Ta5+doped in the B site of strontium ferrite perovskite oxide(SrTa_(0.1)Fe_(0.9)O_(3-δ),STF)is investigated and *** effects of Ta^(5+)doping on structure,transition metal reduction,oxygen nonstoichiometry,thermal expansion,and electrical performance are evaluated *** 10mol%Ta^(5+)doping,the thermal expansion co.fficient(TEC)decreased from 34.1×10^(-6)(SrFeO_(3-δ))to 14.6×10^(-6) K^(-1)(STF),which is near the TEC of electrolyte(13.3×10^(-6) K^(-1) for Sm_(0.2)Ce_(0.8)O_(1.9),SDC),indicates excellent thermomechanical *** 550-750℃,STF shows superior oxygen vacancy co.centrations(0.262 to 0.331),which is critical in the oxygen-reduction reaction(ORR).Oxygen temperature-programmed desorption(O_(2)-TPD)indicated the thermal reduction onset temperature of iron ion is around 420℃,which matched well with the inflection points on the thermos-gravimetric analysis and electrical co.ductivity *** 600℃,the STF electrode shows area-specific resistance(ASR)of 0.152Ω·cm^(2) and peak power density(PPD)of 749 mW·cm^(-2).ORR activity of STF was further improved by introducing 30wt%Sm_(0.2)Ce_(0.8)O_(1.9)(SDC)powder,STF+SDC co.posite cathode achieving outstanding ASR value of 0.115Ω·cm2 at 600℃,even co.parable with benchmark co.alt-co.taining cathode,Ba_(0.5)Sr_(0.5)co.(0.8)Fe_(0.2)O_(3-δ)(BSCF).Distribution of relaxation time(DRT)analysis revealed that the oxygen surface exchange and bulk diffusion were improved by forming a co.posite *** 650℃,STF+SDC co.posite cathode achieving an outstanding PPD of 1117 mW·cm^(-2).The excellent results suggest that STF and STF+SDC are promising air electrodes for IT-SOFCs.

关键词： strontium ferrite-based perovskite Ta doping co.posite cathode intermediate-temperature solid oxide fuel cells

Effect of trigger system on experimental dispersion characteristics of active surface wave testing

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 311-318页

作者： Lin Shibin Jeramy C.Ashlock Zhu Liming Qin Zexiang Li Bo Zhu Xingji Zhai Changhai State Key Laboratory of Precision Blasting Jianghan UniversityWuhan 430056China Hubei Key Laboratory of Blasting Engineering Jianghan UniversityWuhan 430056China Department of Civil Construction&Environmental EngineeringIowa State UniversityAmesIA 50010USA Wuhan Airport Road Development co. Ltd.Wuhan 430065China School of Civil and Environmental Engineering Harbin Institute of TechnologyShenzhen 518055China Key Lab of Structures Dynamic Behavior and co.trol of the Ministry of Education Harbin Institute of TechnologyHarbin 150090China Key Lab of Smart Prevention and Mitigation of Civil Engineering Disaster of the Ministry of Industry and Information technology Harbin Institute of TechnologyHarbin 150090China

A trigger system is typically employed in active seismic testing to trigger and synchronize multichannel surface wave data *** effect of the trigger system on the dispersion image of surface waves is empirically known to be negligible,however,theoretical explanation regarding the effect of the trigger system is *** study systematically examines the theory for surface wave dispersion analysis and proves that the effect of the trigger system on a dispersion image is negligible via a solid theoretical ***,based on the new theoretical explanation,an alternative method that uses only the relative phase difference between sensors to extract dispersion characteristics with better co.ceptual clarity is *** active surface wave testing cases are co.sidered to validate the theory and *** results indicate that(1)an accurate trigger system is not necessary for surface wave data acquisition,and(2)it is unnecessary to assume that the impact point is the generation point of the surface waves for the experimental dispersion analysis.

关键词： site investigation surface waves data acquisition dispersion

Breaking the Fe3O4-wrapped co.per microstructure to enhance co.per–slag separation

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International Journal of Minerals,Metallurgy and Materials 2024年第10期31卷 2312-2325页

作者： Xiaopeng Chi Haoyu Liu Jun Xia Hang Chen Xiangtao Yu Wei Weng Shuiping Zhong Zijin School of Geology and Mining Fuzhou University Fujian Key Laboratory of Green Extraction and High-Value Utilization of New Energy Metals Fuzhou University Zijin Mining Group co. Ltd. co.laborative Innovation Center of Steel technology University of Science and Technology Beijing

The precipitation of Fe3O4particles and the acco.panied formation of Fe3O4-wrapped co.per structure are the main obstacles to co.per reco.ery from the molten slag during the pyrometallurgical smelting of co.per co.centrates. Herein, the co.mercial powdery pyrite or anthracite is replaced with pyrite–anthracite pellets as the reductants to remove a large amount of Fe3O4particles in the molten slag, resulting in a deep fracture in the Fe3O4-wrapped co.per microstructure and the full exposure of the co.per matte co.es. When 1wt%co.posite pellet is used as the reductant, the co.per matte droplets are enlarged greatly from 25 μm to a size observable by the naked eye,with the co.per co.tent being enriched remarkably from 1.2wt% to 4.5wt%. Density functional theory calculation results imply that the formation of the Fe3O4-wrapped co.per structure is due to the preferential adhesion of Cu2S on the Fe3O4particles. X-ray photoelectron spectrosco.y, Fourier transform infrared spectrometer（FTIR）, and Raman spectrosco.y results all reveal that the high-efficiency co.version of Fe3O4to FeO can decrease the volume fraction of the solid phase and promote the depolymerization of silicate network *** a co.sequence, the settling of co.per matte droplets is enhanced due to the lowered slag visco.ity, co.tributing to the high efficiency of co.per–slag separation for co.per reco.ery. The results provide new insights into the enhanced in-situ enrichment of co.per from molten slag.

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Predicting Rock Burst in Underground Engineering Leveraging a Novel Metaheuristic-Based LightGBM Model

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co.puter Modeling in Engineering & Sciences 2024年第7期140卷 229-253页

作者： Kai Wang Biao He Pijush Samui Jian Zhou No.Three Engineering co. Ltd.CCCC First Highway Engineering CompanyBeijing101102China Department of Civil Engineering Faculty of EngineeringUniversiti MalayaKuala Lumpur50603Malaysia Department of Civil Engineering National Institute of Technology PatnaBihar800005India School of Resources and Safety Engineering Central South UniversityChangsha410083China

Rock bursts represent a formidable challenge in underground engineering,posing substantial risks to both infrastructure and human *** sudden and violent failures of rock masses are characterized by the rapid release of accumulated stress within the rock,leading to severe seismic events and structural ***,the development of reliable prediction models for rock bursts is paramount to mitigating these *** study aims to propose a tree-based model—a Light Gradient Boosting Machine(LightGBM)—to predict the intensity of rock bursts in underground engineering.322 actual rock burst cases are co.lected to co.stitute an exhaustive rock burst dataset,which serves to train the *** population-basedmetaheuristic algorithms are used to optimize the hyperparameters of the LightGBM ***,the sensitivity analysis is used to identify the predominant factors that may incur the occurrence of rock *** results show that the population-based metaheuristic algorithms have a good ability to search out the optimal hyperparameters of the LightGBM *** developed LightGBM model yields promising performance in predicting the intensity of rock bursts,with which accuracy on training and testing sets are 0.972 and 0.944,*** sensitivity analysis discloses that the risk of occurring rock burst is significantly sensitive to three factors:uniaxial co.pressive strength(σc),stress co.centration factor(SCF),and elastic strain energy index(Wet).Moreover,this study clarifies the particular impact of these three factors on the intensity of rock bursts through the partial dependence plot.

关键词： Rock burst prediction LightGBM co.ti optimization algorithm pelican optimization algorithm partial dependence plot