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Two-phase sink vortex suction mechanism and penetration dynamic characteristics in ladle teeming process

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Journal of Iron and Steel Research International 2017年第7期24卷 669-677页

作者： Da-peng Tan Ye-sha.Ni Li-bin Zhang Key Laboratory of E & M Ministry of Education & Zhejiang ProvinceZhejiang University of Technology

At the late stage of continuous casting（CC）ladle teeming,sink vortex can suck the liquid slag into tundish,and cause negative influences on the cleanliness of molten *** address this issue,a twophase fluid mechanical modeling method for ladle teeming was ***,a dynamic model for vortex suction process was built,and the profiles of vortex flow field were ***,based on the level set method（LSM）,a two-phase 3Dinterface coupling model for slag entrapment was ***,in combination with high-order essentially non-oscillatory（ENO）and total variation diminishing（TVD）methods,a LSM-based numerical solution method was proposed to obtain the 3Dcoupling evolution regularities in vortex suction *** results show that the vortex with higher kinetic energy can form an expanded sandglass-sha.e region with larger slag fraction and lower rotating velocity;there is a pressure oscillation phenomenon at the vortex penetration state,which is caused by the energy shock of two-phase vortex penetration coupling.

关键词： Ladle teeming Sink vortex Suction mechanism Two-phase coupling Level set method Pressure oscillation

Genesis of the Maoling gold deposit in the Liaodong Peninsula:Constraints from a combined fluid inclusion,C-H-O-S-Pb-He-Ar isotopic and geochronological studies

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Geoscience Frontiers 2022年第4期13卷 11-33页

作者： peng Zhang Linlin Kou Yan Zhao Deming sha Shenyang Geological Survey Center China Geological SurveyShenyang 110034China

The large tonnage Maoling gold deposit(25 t@3.2 g/t)is located in the southwest Liaodong Peninsula,North China *** deposit is hosted in the Paleoproterozoic metamorphic *** stages of mineralization were identified in the deposit:(stageⅠ)quartz-arsenopyrite±pyrite,(stageⅡ)quartz-goldarsenopyrite-pyrrhotite,(stageⅢ)quartz-gold-polymetallic sulfide,and(stageⅣ)*** this paper,we present fluid inclusion,C-H-O-S-Pb-He-Ar isotope data,zircon U-Pb,and gold-bearing sulfide(*** and pyrrhotite)Rb-Sr age of the Maoling gold deposit to constrain its genesis and ore-forming *** types of fluid inclusions were distinguished in quartzbearing veins,including liquid-rich two-phase(WL type),gas-rich two-phase(GL type),and daughter mineral-bearing fluid inclusions(S type).Fluid inclusions data show that the homogenization at temperatures 197 to 372°C for stageⅠ,126 to 319°C for stageⅡ,119 to 189°C for stageⅢ,and 115 to 183°C for stageⅣ,with corresponding salinities of 3.7 to 22.6 wt.%,4.7 to 23.2 wt.%,5.3 to 23.2 wt.%,and 1.7 to14.9 wt.%Na Cl equiv.,*** boiling was the critical factor controlling the gold and associated sulfide precipitation at *** and oxygen stable isotopic analyses for quartz yielded δ^(18)O=-5.0‰ to 9.8‰ and δD=-133.5‰ to-77.0‰.Carbon stable isotopic analyses for calcite and ankerite yielded δ^(13)C=-2.3‰to-1.2‰ and O=7.9‰ to 14.1‰.The C-H-O isotope data show that the oreforming fluids were originated from magmatic water with meteoric water input during *** inclusions in arsenopyrite have ^(3)He/^(4)He ratios of 0.002 Ra to 0.054 Ra,and ^(40)Ar/^(36)Ar rations of 1225 to 3930,indicating that the ore-forming fluids were dominantly derived from crustal sources almost no mantle *** isotopic values of Maoling fine-grained granite range from6.‰1 to 9.8‰,with a mean of 7.7‰,δ^(34)S values of arsenopyrite from the mineralized phyllite(host rock)range fr

关键词： Geochronology Fluid inclusions Isotope geochemistry Maoling gold deposit Liaodong Peninsula

Parametric identification of time-varying systems from free vibration using intrinsic chirp component decomposition

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Acta Mechanica Sinica 2020年第1期36卷 188-205页

作者： sha.Wei Shiqian Chen Xingjian Dong Zhike peng Wenming Zhang School of Mechanics and Engineering Science Shanghai UniversityShanghai200072China sha.ghai Institute of Applied Mathematics and Mechanics Shanghai UniversityShanghai200072China sha.ghai Key Laboratory of Mechanics in Energy Engineering Shanghai UniversityShanghai200072China State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai200240China

Time-varying systems are applied extensively in practical applications,and their related parameter identification techniques are of great significance for structural health monitoring of time-varying *** improve the identification accuracy for time-varying systems,this study puts forward a novel parameter identification approach in the time-frequency domain using intrinsic chirp component decomposition(ICCD).ICCD is a powerful tool for signal decomposition and parameter extraction,with good signal reconstruction capability in a high-noise *** maintain good identification effects for the time-varying system in a noisy environment,the proposed method introduces a redundant Fourier model for the non-stationary signal,including instantaneous frequency(IF)and instantaneous amplitude(IA).The accuracy and effectiveness of the proposed approach are demonstrated by a single-degree-of-freedom system with three types of time-varying parameters,as well as an example of a multi-degree-of-freedom *** effects of different levels of measured noise on the identified results are also discussed in *** results show that the proposed method is very effective in tracking the smooth,periodical,and non-smooth variations of time-varying systems over the entire identification time period even when the response signal is contaminated by intense noise.

关键词： System identification Time-varying system Time-frequency domain Intrinsic chirp component decomposition

Selective catalytic reduction of NO_(x) with NH_(3) over core-shell Ce@W catalyst

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Journal of Rare Earths 2023年第6期41卷 959-964,I0006页

作者： Ruiyang Chen sha.peng Yao Wang Xiaoying Qi Zhiming Liu State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China Beijing Key Laboratory of Energy Environmental Catalysis Beijing University of Chemical TechnologyBeijing 100029China CAS Key Laboratory of Standardization and Measurement for Nanotechnology CAS Center for Excellence in NanoscienceNational Center for Nanoscience and TechnologyBeijing 100190China

An environmentally benign WO_(3) wrapped cubic CeO_(2) core-shell catalyst(Ce@W)was developed for the selective catalytic reduction of NO_(x) with NH_(3).Compared with CeW particles prepared via the conventional co-precipitation method,this core-shell catalyst not only displays higher tolerance to SO_(2) and H_(2)O,but also exhibits a wider activity tempe rature window of 250-450℃,in which NO_(x)conversion and N_(2) selectivity reaches 100%.The improved performance of Ce@W catalysts can be contributed to the strong interactions between CeO_(2)(100) and WO_(3),which generates more Ce^(3+) and surface chemisorbed *** situ diffuse reflectance infrared Fourier transform spectroscopy(DRIFTs)reveal that the more thermally stable Br?nsted acid sites on Ce@W lead to its excellent high-temperature activity.

关键词： NH_(3)-SCR Nitrogen oxides Ce@W In situ DRIFTs Rare earths

An Efficient Solid State Method for Deoximation under Mild Conditions

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Chinese Chemical Letters 2006年第12期17卷 1559-1562页

作者： Wang ZHOU Qian He LI sha.peng Institute of Fine Catalysis and Synthesis Hunan Normal University Changsha 410080

Oximes of ketones and aldehydes are efficiently converted to the corresponding carbonyl compounds, using a combination of NaHSO4.H20 and paraformaldehyde in good to excellent yields under solid state conditions at roo... 详细信息

关键词： Solid state deoximation oxime carbonyl compound.

Modal identification of multi-degree-of-freedom structures based on intrinsic chirp component decomposition method

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Applied Mathematics and Mechanics(English Edition) 2019年第12期40卷 1741-1758页

作者： sha.WEI Shiqian CHEN Zhike peng Xingjian DONG Wenming ZHANG State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University

Modal parameter identification is a mature ***,there are some challenges in its practical applications such as the identification of vibration systems involving closely spaced modes and intensive noise *** paper proposes a new time-frequency method based on intrinsic chirp component decomposition(ICCD)to address these *** this method,a redundant Fourier model is used to ameliorate border distortions and improve the accuracy of signal *** effectiveness and accuracy of the proposed method are illustrated using three examples:a cantilever beam structure with intensive noise contamination or environmental interference,a four-degree-of-freedom structure with two closely spaced modes,and an impact test on a cantilever rectangular *** comparison with the identification method based on the empirical wavelet transform(EWT),it is shown that the presented method is effective,even in a high-noise environment,and the dynamic characteristics of closely spaced modes are accurately determined.

关键词： modal identification closely spaced mode time-frequency domain intrinsic chirp component decomposition(ICCD) multi-degree-of-freedom(MDOF) system

Regularity and sensitivity analysis of main parameters of plate effects on the aerodynamic braking drag of a high-speed train

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Transportation Safety and Environment 2023年第2期5卷 71-78页

作者： peng Li sha.Huang Yong Liu Jiqiang Niu School of Rail Transport Wuyi UniversityJiangmen 529020GuangdongChina School of Mechanical Engineering Southwest Jiaotong UniversityChengdu 610031SichuanChina Maglev Technology Key Laboratory of Railway Industry Tongji UniversityShanghai 201804China

With increase of train speed,braking plate technology has a good application prospect in the high-speed stage of the *** on the 1/8 scaled symmetrical train model composed of two half cars,the Reynolds Av era ge Navier-Stokes(RANS)equations and Shear Stress Transfer(SST)k-ωturbulence model are adopted to simulate the aerodynamic performance of the train with *** aer odynamic dra g de pendence of single par ameter of the plate(sha.e,area,angle,position and n umber)is anal ysed,and identification resear c h of the main aerodynamic parameters of the plate is carried *** numerical settings used in this paper are verified by wind tunnel test *** show that the braking plate with an aspect ratio of one has better performance on aerodynamic *** area,opening angle and number of plates are basically positively correlated with the total aerodynamic drag of the target car and *** anging plates at the downstream of the vehicle is a good method of raising total aerodynamic *** the range of plate parameter design in this paper,by using orthogonal design of experiment and the method of range analysis and analysis of variance,the influence degrees of plate parameters on aer odynamic dra g ar e determined,and the order is n umber,ar ea and opening angle of *** research results provide theoretical support for the design and safe operation of high-speed trains with aerodynamic braking plates.

关键词： high-speed train braking plate aerodynamic drag orthogonal design parameter identification

Development of a key-variable-based parallel HVAC energy predictive model

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Building Simulation 2022年第7期15卷 1193-1208页

作者： Huajing sha.peng Xu Chengchu Yan Ying Ji Kenan Zhou Feiran Chen Terminus(sha.ghai)Information Technology Co. LTDShanghai 200062China Deportment of Mechanical and Energy Engineering Tongji UniversityShanghai 201804China Department of Urban Construction Nanjing Tech UniversityNanjing 211816China Beijing Key Laboratory of Green Built Environment and Energy Efficient Technology Beijing University of TechnologyBeijing00124China China Southern Power Grid Guangdong Fosha. Power Supply Bureau GuangdongChina

Building heating,ventilation,and air conditioning(HVAC)systems consume large amounts of energy,and precise energy prediction is necessary for developing various energy-efficiency *** prediction using data-driven models has received increasing attention in recent ***,two types of driven models are used for building energy prediction:sequential and parallel predictive *** latter uses the historical energy of the target building as training data to predict future energy ***,for newly built buildings or buildings without historical data records,the energy can be estimated using the parallel model,which employs the energy data of similar buildings as training *** second predictive model is seldom studied because the model input feature is difficult to identify and ***,we propose a novel key-variable-based parallel HVAC energy predictive *** model has informative input features(including meteorological data,occupancy activity,and key variables representing building and system characteristics)and a simple architecture.A general key-variable screening toolkit which was more versatile and flexible than present parametric analysis tools was developed to facilitate the selection of key variables for the parallel HVAC energy predictive model.A case study is conducted to screen the key variables of hotel buildings in eastern China,based on which a parallel chiller energy predictive model is trained and *** average cross-test error measured in terms of the coefficient of variation of the root mean square error(CV-RMSE)and normalized mean bias error(NMBE)of the parallel chiller energy predictive model is approximately 16%and 8.3%,which is acceptable for energy prediction without using historical energy data of the target building.

关键词： HVAC energy prediction data-driven model sequential predictive model parallel predictive model key-variable screening sensitivity analysis

Laser solid-phase synthesis of single-atom catalysts

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Light(Science & Applications) 2021年第9期10卷 1736-1749页

作者： Yudong peng Jianyun Cao Yang sha.Wenji Yang Lin Li Zhu Liu Department of Materials School of Natural SciencesThe University of ManchesterManchesterM139PLUK National Graphene Institute The University of ManchesterManchesterM139PLUK Laser Processing Research Centre Department of MechanicalAerospace and Civil EngineeringThe University of ManchesterManchesterM139PLUK

Single-atom catalysts(SACs)with atomically dispersed catalytic sites have shown outstanding catalytic performance in a variety of ***,the development of facile and high-yield techniques for the fabrication of SACs remains *** this paper,we report a laser-induced solid-phase strategy for the synthesis of Pt SACs on graphene *** by rapid laser scanning/irradiation of a freeze-dried electrochemical graphene oxide(EGO)film loaded with chloroplatinic acid(H2PtCl6),we enabled simultaneous pyrolysis of H2PtCl6 into SACs and reduction/graphitization of EGO into *** rapid freezing of EGO hydrogel film infused with H2PtCl6 solution in liquid nitrogen and the subsequent ice sublimation by freeze-drying were essential to achieve the atomically dispersed *** pulsed infrared(IR;1064 nm)and picosecond pulsed ultraviolet(UV;355 nm)lasers were used to investigate the effects of laser wavelength and pulse duration on the SACs formation *** atomically dispersed Pt on graphene support exhibited a small overpotential of−42.3 mV at−10 mA cm−2 for hydrogen evolution reaction and a mass activity tenfold higher than that of the commercial Pt/C *** method is simple,fast and potentially versatile,and scalable for the mass production of SACs.

关键词： mechanism. synthesis dispersed