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Hydrogen Permeation Properties of Perovskite-type BaCe_(0.9)Mn_(0.1)O_(3-δ)Dense Ceramic Membrane

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Chinese Chemical Letters 2001年第10期12卷 937-940页

作者： Guang Tao LI Guo Xing XIONG shi shan sheng Wei Shen YANG State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023

The electrical conduction properties of dense BaCe0.9Mn0.1O3-d (BCM10) membrane were investigated in the temperature range of 600-900oC. High ionic and electronic conductivities at elevated temperatures make BCM10 a potential ceramic material for hydrogen separation. Hydrogen permeation through BCM10 membranes was studied using a high- temperature permeation cell. Little hydrogen could be detected at the sweep side. However, appreciable hydrogen can permeate through BCM10 membrane coated with porous platinum black, which shows that the process of hydrogen permeation through BCM10 membranes was controlled by the catalytic decomposition and recomposition of hydrogen on the surfaces of BCM10 membranes.

关键词： Hydrogen permeation dense ceramic membranes barium cerate proton and electron conductivity.

Sol-Gel Method for Preparation of LiLaNiO/γ-Al_2O_3 Catalyst over Monoliths used in POM Reaction

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Chinese Chemical Letters 2001年第3期12卷 253-256页

作者： Ran RAN Guo Xing XIONG Yu Hong ZHANG shi shan sheng Wei Shen YANG State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesP.O.Box 110Dalian 116023

A new method for preparing LiLaNiO/γ(-Al2O3 monolithic catalyst was described and discussed. The catalyst, which was supported over the monolith, was evaluated in a POM to syngas process. Relative stable catalytic properties during the 120 hours operation at atmospheric pressure were found for the catalyst. Under the high space velocity of 9.0×104l/(kg·（h）（CH4）, the conversion of methane came to 95.5%, and the selectivity of carbon monoxide was not below 96.0% at 1123K when ratio of the feedstock （CH4/O2） was equal to 2.0.

关键词： Monolith LiLaNiO/γ-Al2O3 catalyst POM syngas.

Research on the macro-and meso-mechanical properties of frozen sand mold based on Hertz-Mindlin with Bonding model

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Particuology 2024年第5期88卷 176-191页

作者： Jianpei shi Zhongde shan Haoqin Yang College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjing 210016China State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China College of Material Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 210016China

In this study,macro-and meso-mechanical properties of frozen sand molds were discussed based on the Hertz-Mindlin with Bonding(HMB)***-Burman,steepest ascent,and central composite designs were utilized to propose a parameter calibration *** effects of mesoscopic parameter variations on the compressive strength and average gradient of stress-strain were investigated through response surface method *** showed that the relative error between the simulated and measured repose angle is 3.1%under calibrated intrinsic contact *** compressive strength and average stress-strain gradient primarily depend on the normal and shear stiffness per unit area,as well as the particle size and porosity of the silica ***,taking load-displacement curves of three frozen sand molds with different geometric characteristics as the target value,the reliability and effectiveness of the frozen sand mold HMB model were verified through uniaxial compression tests and discrete element simulations.

关键词： Frozen sand mold Hertz-Mindlin with Bonding model Uniaxial compression test Discrete element method Mechanical properties

Cofeeding of Methane and Ethane to Produce Syngas over a LiLaNiO/γ-Al_2O_3 Catalyst

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Chinese Chemical Letters 2000年第2期11卷 175-178页

作者： sheng Lin LIU Guo Xing XIONG Long Ya XU shi shan sheng Wei Shen YANG (State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, CAS, P. O. Box 1 10. Dalian 116023) CAS Dalian Inst Chem Phys State Key Lab Catalysis Dalian 116023 Peoples R China

Partial oxidation of methane and ethane to syngas over a LiLaNIO/γ-Al_2O_3 catalyst was investigated with a flow-reactor, XPS and XRD. Excellent reaction performance for CH_4-C_2H_6-O_2 to syngas over the LiLaNiO/γ-Al_2O_3 catalyst was achieved at 1073K, obtaining CO selectivity of 90%-95% and CH_4 conversion of ~ 97%, with a wide range of C_2H_6 content in the feed and of space velocity.

关键词： partial oxidation cofeeding of methane and ethane syngas LiLaNiO/γ-Al_2O_3.

New formula for predicting the plastic buckling pressure of steel torispherical heads under internal pressure

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第8期25卷 618-630页

作者： sheng YE Keming LI Jinyang ZHENG shan SUN Institute of Process Equipment Zhejiang UniversityHangzhou 310027China Engineering Research Center for High Pressure Process Equipment and Safety of Ministry of Education Hangzhou 310027China State Key Laboratory of Fluid Power and Mechatronic Systems Hangzhou 310058China

Thin-walled torispherical heads under internal pressure can fail by plastic buckling because of compressive circumferential stresses in the head ***,existing formulas still have limitations,such as complicated expressions and low accuracy,in determining buckling *** this paper,we propose a new formula for calculating the buckling pressure of torispherical heads based on elastic-plastic analysis and experimental ***,a finite element(FE)method based on the arc-length method is established to calculate the plastic buckling pressure of torispherical heads,considering the effects of material strain hardening and geometrical *** buckling pressure results calculated by the FE method in this paper have good consistency with those of BOSOR5,which is a program for calculating the elastic-plastic bifurcation buckling pressure based on the finite difference energy ***,the effects of geometric parameters,material parameters,and restraint form of head edge on buckling pressure are ***,a new formula for calculating plastic buckling pressure is developed by fitting the curve of FE results and introducing a reduction factor determined from experimental ***,based on the experimental results,we compare the predictions of the new formula with those of existing *** is shown that the new formula has a higher accuracy than the existing ones.

关键词： Torispherical head Plastic buckling Elastic-plastic analysis Prediction formula Finite element method

Design and performance evaluation of a large field-of-view dual-particle time-encoded imager based on a depth-of-interaction detector

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Nuclear Science and Techniques 2024年第4期35卷 1-14页

作者： Dong Zhao Xu-Wen Liang Ping-Kun Cai Wei Cheng Wen-Bao Jia Da-Qian Hei Qing shan Yong-sheng Ling Chao shi Department of Nuclear Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing 211106China Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions Suzhou 215000China School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China

Time-encoded imaging is useful for identifying potential special nuclear materials and other radioactive sources at a *** this study,a large field-of-view time-encoded imager was developed for gamma-ray and neutron source hotspot imaging based on a depth-of-interaction(DOI)*** imager primarily consists of a DOI detector system and a rotary dual-layer cylindrical coded *** EJ276 plastic scintillator coupled with two SiPMs was designed as the DOI detector to increase the field of view and improve the imager *** difference in signal time at both ends and the log of the signal amplitude ratio were used to calculate the interaction position *** position resolution of the DOI detector was calibrated using a collimated Cs-137 source,and the full width at half maximum of the reconstruction position of the Gaussian fitting curve was approximately 4.4 *** DOI detector can be arbitrarily divided into several units to independently reconstruct the source distribution *** unit length was optimized via Am-Be source-location experiments.A multidetector filtering method is proposed for image *** method can effectively reduce image noise caused by poor DOI detector position *** vertical field of view of the imager was(-55°,55°)when the detector was placed in the center of the coded mask.A DT neutron source at 20 m standoff could be located within 2400 s with an angular resolution of 3.5°.

关键词： Time-encoded imager Depth-of-interaction detector Dual-particle imaging Hotspot imaging

Effects of data smoothing and recurrent neural network(RNN)algorithms for real-time forecasting of tunnel boring machine(TBM)performance

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1538-1551页

作者： Feng shan Xuzhen He Danial Jahed Armaghani Daichao sheng School of Civil and Environmental Engineering University of Technology SydneyNSW2007Australia

Tunnel boring machines(TBMs)have been widely utilised in tunnel construction due to their high efficiency and *** predicting TBM performance can improve project time management,cost control,and risk *** study aims to use deep learning to develop real-time models for predicting the penetration rate(PR).The models are built using data from the Changsha metro project,and their performances are evaluated using unseen data from the Zhengzhou Metro *** one-step forecast,the predicted penetration rate follows the trend of the measured penetration rate in both training and *** autoregressive integrated moving average(ARIMA)model is compared with the recurrent neural network(RNN)*** results show that univariate models,which only consider historical penetration rate itself,perform better than multivariate models that take into account multiple geological and operational parameters(GEO and OP).Next,an RNN variant combining time series of penetration rate with the last-step geological and operational parameters is developed,and it performs better than other models.A sensitivity analysis shows that the penetration rate is the most important parameter,while other parameters have a smaller impact on time series *** is also found that smoothed data are easier to predict with high ***,over-simplified data can lose real characteristics in time *** conclusion,the RNN variant can accurately predict the next-step penetration rate,and data smoothing is crucial in time series *** study provides practical guidance for TBM performance forecasting in practical engineering.

关键词： Tunnel boring machine(TBM) Penetration rate(PR) Time series forecasting Recurrent neural network(RNN)

In-situ growth of MIL-53(Fe)on charcoal sponge as a highly efficient and recyclable photocatalyst for removal of Cr(Ⅵ)

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Rare Metals 2024年第9期43卷 4344-4355页

作者： Zhuo-Fan Yu Ye Yang Hai-Feng Zhuang sheng-Dao shan Mihail-Simion Beldean-Galea Qing-Quan Xue Xiao-Feng Shen shi-Jie Li Key Laboratory of Recycling and Eco-Treatment of Waste Biomass of Zhejiang Province School of Environmental and Natural ResourcesZhejiang University of Science and TechnologyHangzhou 310023China Faculty of Environmental Science and Engineering Babes-Bolyai University400294 Cluj-NapocaRomania Key Laboratory of Pollution Exposure and Health Intervention of Zhejiang Province Interdisciplinary Research Academy(IRA)Zhejiang Shuren UniversityHangzhou 310015China National Engineering Research Center for Marine Aquaculture Institute of Innovation&ApplicationZhejiang Ocean UniversityZhoushan 316022China

The application of metalDorganic frameworks(MOFs)is hindered by several crucial factors,including low photocatalytic efficiency,poor stability and challenges in *** this study,MIL-53(Fe)was grown in situ on a charcoal sponge(CS)with a large surface area,excellent mechanical properties,and high photocatalytic efficiency using a solvothermal method,thus addressing the above-mentioned shortcomings of MOF ***,CS/MIL-53(Fe)has an amazing light-harvesting capacity in the visible range,leading to a significant improvement in the utilization of *** results of the experiments indicate that CS/MIL-53(Fe)displays a higher photocatalytic activity(87%Cr(Ⅵ))when exposed to visible light than CS(58%)or MIL-53(Fe)(27%),attributing to the increased separation of photogenerated carriers.e-is the main reactive radical and dominates the photocatalytic reduction process,rooting from that e-can reduce Cr(Ⅵ)to low-toxicity Cr(Ⅲ).This study presents a novel method for constructing photocatalysts with large surface areas,superior mechanical characteristics,and enhanced photocatalytic ***,it achieves the resource utilization of agricultural and forestry waste.

关键词： Cr(Ⅵ) Charcoal sponge MIL-53(Fe) Photocatalysis Light absorption

Influences of shale microstructure on mechanical properties and bedding fractures distribution

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Petroleum Science 2024年第3期21卷 1944-1954页

作者： Ming-Zhe Gu Mao sheng shi-Zhong Cheng Fan-Hao Gong Gen-sheng Li State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum-BeijingBeijing2249China College of Petroleum Engineering China University of Petroleum-BeijingBeijing102249China Shenyang Center of China Geological Survey ShenyangLiaoning110034China

The difference in microstructure leads to the diversity of shale mechanical properties and bedding fractures distribution *** this paper,the microstructure and mechanical properties of Longmaxi marine shale and Qingshankou continental shale were studied by X-ray diffractometer(XRD),field emission scanning electron microscope(FE-SEM)with mineral analysis system,and ***,the typical bedding layers area was properly stratified using Focused Ion Beam(FIB),and the effects of microstructure and mechanical properties on the distribution patterns of bedding fractures were *** results show that the Longmaxi marine shale sample contains more clay mineral grains,while the Qingshankou continental shale sample contains more hard brittle mineral grains such as *** Longmaxi marine shale sample,hard brittle minerals with grain sizes larger than 20μm is18.24%and those with grain sizes smaller than 20μm is 16.22%.For Qingshankou continental shale sample,hard brittle minerals with grain sizes larger than 20μm is 40.7%and those with grain sizes smaller than 20μm is 11.82%.In comparison to the Qingshankou continental shale sample,the Longmaxi marine shale sample has a lower modulus,hardness,and *** shales are formed by alternating coarse-grained and fine-grained layers during *** average single-layer thickness of Longmaxi marine shale sample is greater than Qingshankou continental shale *** two types of shale have similar bedding fractures distribution patterns and fractures tend to occur in the transition zone from coarse-grained to fine-grained *** orientation of the fracture is usually parallel to the bedding plane and detour occurs in the presence of hard brittle *** fracture distribution density of the Longmaxi marine shale sample is lower than that of the Qingshankou continental shale sample due to the strong heterogeneity of the Qingshankou continental *** current resea

关键词： Shale Nanoindentation Microstructure Mechanical property Fracture