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International Journal of Minerals,Metallurgy and Materials 2015年第4期22卷 437-445页

作者： Yan-bo Wu Jun Bi Ting Lou tie-ben song Hong-quan Yu School of Environmental and Chemical Engineering Dalian Jiaotong University

Polyacrylonitrile （PAN）, PAN/cellulose acetate （CA）, and PAN/CA-Ag based activated carbon nanofiber （ACNF） were prepared using electrostatic spinning and further heat treatment. Thermogravimetrylifferential scanning calorimetry （TG-DSC） analysis indicated that the addition of CA or Ag did not have a significant impact on the thermal decomposition of PAN materials but the yields of fibers could be improved. Scanning electron microscopy （SEM） analysis showed that the micromorphologies of produced fibers were greatly influenced by the viscosity and conductivity of precursor solutions. Fourier transform infrared spectroscopy （FT-IR） analysis proved that a cyclized or trapezoidal structure could form and the carbon scaffold composed of C=C bonds appeared in the PAN-based ACNFs. The characteristic dif- fraction peaks in X-ray diffraction （XRD） spectra were the evidence of a turbostratic structure and silver existed in the PAN/CA-Ag based ACNF. Brurmer-Emmett-Teller （BET） analysis showed that the doping of CA and Ag increased surface area and micropore volume of fi- bers; particularly, PAN/CA-Ag based ACNF exhibited the best porosity feature. Furthermore, SO2 adsorption experiments indicated that all the three fibers had good adsorption effects on lower concentrations of SO2 at room temperature; especially, the PAN/CA-Ag based ACNF showed the best adsorption performance, and it may be one of the most promising adsorbents used in the fields of chemical industry and en- vironment protection.

关键词： activated carbon nanofibers polyacrylonitrile electrospinning adsorption sulfur dioxide

Preparation of metal oxide doped ACNFs and their adsorption performance for low concentration SO_2

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International Journal of Minerals,Metallurgy and Materials 2013年第11期20卷 1102-1106页

作者： Hong-quan Yu Yan-bo Wu tie-ben song Yue Li Yu Shen College of Environmental and Chemical Engineering Dalian Jiaotong University

Metal oxide （TiO2 or Co304） doped activated carbon nanofibers （ACNFs） were prepared by electrospinning. These nanofibers were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, and Brunner- Emmett-Teller method （BET）. The results show that the average diameters of ACNFs were within the range of 200-500 nm, and the lengths were several tens of micrometers. The specific surface areas were 1146.7 m2/g for TiO2-doped ACNFs and 1238.5 m2/g for Co304-doped ACNFs, respectively. The electrospun nanofibers were used for adsorption of low concentration sulfur dioxide （SO2）. The results showed that the adsorption rates of these ACNFs increased with an increase in SO2concentration. When the SO2 concentration was 1.0 μg/mL, the adsorption rates of TiO2-doped ACNFs and Co3Oa-doped ACNFs were 66.2% and 67.1%, respectively. The adsorption rate also increased as the adsorption time increased. When the adsorption time was 40 min, the adsorption rates were 67.6% and 69.0% for TiO2-doped ACNFs and Co304-doped ACNFs, respectively. The adsorption rate decreased as the adsorption temperature increased below 60℃, while it increased as the adsorption temperature increased to more than 60℃.

关键词： activated carbon nanofibers metal oxides electrospinning adsorption sulfur dioxide

Determination of ice jam thickness—A new approach

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Journal of Hydrodynamics 2024年第3期36卷 570-581页

作者： Jun Wang Lian-sheng Sang Fei-hu song tie-jie Cheng Jueyi Sui School of Civil and Water Engineering Hefei University of TechnologyHefei230009China School of Engineering University of Northern British ColumbiaPrince GeorgeCanada

In winter,rivers in cold regions often experience flood disasters resulted from ice jams or ice *** of the variation of ice jam thickness and water level during an ice jammed period are not only a practical need for ice prevention to avoid disaster and plan water resource,but also essential for the development of any mathematical model for predicting the evolution of ice *** far,some equations based on the energy equation have been proposed to describe the relationship between ice jam thickness and water ***,in the derivation of these equations,the local head loss coefficient at the ice jam head and the riverbed slope factor were ***,those reported equations cannot be used to preciously describe the flow energy equation with ice jams and accurately calculate the ice jam thickness and water *** the present study,a more comprehensive theoretical model for hydraulic calculation of ice jam thickness has been derived by considering important and essential factors including riverbed slope and local head loss coefficient at the ice jam ***,based on the data collected from laboratory experiments of ice jam accumulation,the local head loss coefficient at the ice jam head has been calculated,and the empirical equation for calculating the local head loss coefficient has been established by considering flow Froude number and the ratio of ice discharge to flow *** results of this study not only provide a new reference for calculating ice jam thickness and water level,but also present a theoretical basis for accurate CFD simulation of ice jams.

关键词： Energy equation ice jam thickness local head loss coefficient ice jam head riverbed slope

Study of the Lift Force Induced by An Interceptor on A High-Speed Mono-Hull:The Affecting Factors and Estimation Formula

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China Ocean Engineering 2024年第4期38卷 557-571页

作者： DENG Rui HU Yu-xiao HUANG Si-chong song Zhi-jie WANG Shi-gang WU tie-cheng School of Ocean Engineering and Technology Sun Yat-sen Universityand Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China

To find a better way to estimate the lift force induced by an interceptor on a high-speed mono-hull ship,a series of high-speed mono-hull ship models are designed and investigated under different *** lift forces are obtained by numerical calculations and validated by a model test in a towing *** factors that influence the force are the interceptor height,velocity,draft,and deadrise *** relationship between each factor and the induced lift force is investigated and *** found that the induced lift mainly depends on the interceptor height and advancing velocity,and is proportional to the square of the interceptor height and *** results also showed that the effects of the draft and deadrise angle are relatively less important,and the relationship between the induced lift and these two factors is generally *** on the results,a formula including the combined effect of all factors used to estimate the lift force induced by the interceptor is developed based on systematic *** proposed formula could be used to estimate the lift force induced by interceptors,especially under high-speed condition.

关键词： high-speed mono-hull ship interceptor lift force formula lift force towing tank test computational fluid dynamics

Flexible polydimethylsiloxane pressure sensor with micro-pyramid structures and embedded silver nanowires:A novel application in urinary flow measurement

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Nanotechnology and Precision Engineering 2024年第3期7卷 1-12页

作者： ben-song Wang Ang Gao song-Wei Huang Qi-Hong Ning Cheng Zhou Qi-Xiang song Da-XiangCui School of Electronic Information and Electrical Engineering Shanghai Jiao Tong UniversityShanghai 200240China Department of Urology Renji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200240China

Flexible pressure sensors are lightweight and highly sensitive,making them suitable for use in small portable devices to achieve precise measurements of tiny *** article introduces a low-cost and easy-fabrication strategy for piezoresistive flexible pressure *** embedding silver nanowires into a polydimethylsiloxane layer with micro-pyramids on its surface,a flexible pressure sensor is created that can detect low pressure (17.3 Pa) with fast response (<20 ms) and high sensitivity (69.6 mA kPa-1).Furthermore,the pressure sensor exhibits a sensitive and stable response to a small amount of water flowing on its *** this basis,the flexible pressure sensor is innovatively combined with a micro-rotor to fabricate a novel urinary flow-rate meter (uroflowmeter),and results from a simulated human urination experiment show that the uroflowmeter accurately captured all the essential shape characteristics that were present in the pump-simulated urination *** ahead,this research provides a new reference for using flexible pressure sensors in urinary flow-rate monitoring.

关键词： Flexible pressure sensor Silver nanowires Portable device Uroﬂowmeter Healthcare

Effect of post rolling stress on phase transformation behavior of microalloyed dual phase steel

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Journal of Iron and Steel Research International 2024年第3期31卷 688-699页

作者： Wen-quan Sun Sheng-yi Yong tie-heng Yuan Ting-song Yang An-rui He Chao Liu Rui-chun Guo National Engineering Research Center for Advanced Rolling and Intelligent Manufacturing University of Science and Technology BeijingBeijing 100083China

The slow phase transformation of microalloyed dual phase steel makes the nonuniform stress and temperature fields during the post rolling cooling process have a significant impact on the phase transformation *** the relatively slow phase transformation of DP780 steel within the microalloyed dual phase steel series,the influence of stress on the phase transformation behavior of DP780 steel was *** quantify the nonuniform thermal and stress conditions in the steel coil,a thermo-mechanical coupled finite element model of the hot-rolled strip cooling process was *** on the simulation data,DP780 steel was chosen as the research material,and Gleeble 3500 thermal simulation equipment was used for experimental *** thermal expansion curves were analyzed through regression to establish the dynamic model of DP780 steel phase transformation under ***,metallographic analysis was conducted to determine phase transformation type and grain size of DP780 *** results confirmed that the stress promotes the occurrence of semi-diffusion-type bainite ***,an appropriate level of stress facilitates the growth of bainitic grains,while the increased stress inhibits the growth of ferritic grains.

关键词： Microalloyed dual phase steel Stress Bainitic transformation Grain Finite element method

Full waveform inversion based on hybrid gradient

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Petroleum Science 2024年第3期21卷 1660-1670页

作者： Chuang Xie Zhi-Liang Qin Jian-Hua Wang Peng song Heng-Guang Shen Sheng-Qi Yu ben-Jun Ma Xue-Qin Liu Qingdao Innovation and Development Base Harbin Engineering UniversityQingdao266000ShandongChina Qingdao Innovation and Development Center Harbin Engineering UniversityQingdao266000ShandongChina CNOOC Research Institute Co. Ltd.Beijing100028China College of Marine Geoscience Ocean University of ChinaQingdao266100ShandongChina Weihai Sunfull Geophysical Exploration Equipment Co. Ltd.Weihai264209ShandongChina

The low-wavenumber components in the gradient of full waveform inversion(FWI)play a vital role in the stability of the ***,when FWI is implemented in some high frequencies and current models are not far away from the real velocity model,an excessive number of low-wavenumber components in the gradient will also reduce the convergence rate and inversion *** solve this problem,this paper firstly derives a formula of scattering angle weighted gradient in FWI,then proposes a hybrid *** hybrid gradient combines the conventional gradient of FWI with the scattering angle weighted gradient in each inversion frequency band based on an empirical formula derived *** weighted hybrid mode,we can retain some low-wavenumber components in the initial lowfrequency inversion to ensure the stability of the inversion,and use more high-wavenumber components in the high-frequency inversion to improve the convergence *** results of synthetic data experiment demonstrate that compared to the conventional FWI,the FWI based on the proposed hybrid gradient can effectively reduce the low-wavenumber components in the gradient under the premise of ensuring inversion *** also greatly enhances the convergence rate and inversion accuracy,especially in the deep part of the *** the field marine seismic data experiment also illustrates that the FWI based on hybrid gradient(HGFWI)has good stability and adaptability.

关键词： Full waveform inversion Hybrid gradient Scattering angle weighted Low-wavenumber component

Hierarchical Reduced Graphene Oxide-MnO_(2)@Polypyrrole Coaxial Nanotube Composite Hydrogel as a Potential Adsorbent for Cr(Ⅵ)Removal

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Journal of Wuhan University of Technology(Materials Science) 2024年第5期39卷 1287-1293页

作者： LIU ben XU Yaowei TONG Yuxing WANG Ziwei LIU Zhichang YAN Qunshan JI Jiayou GAO song LI Shaoping China Tobacco Hubei Industrial Co. LtdWuhan 430040China Hubei Xinye Reconstituted Tobacco Development Co. Ltd.Wuhan 430056China Applied Technology Research of Reconstituted Tobacco Hubei Province Key Laboratory Wuhan 430040China School of Materials Science and Engineering Wuhan Institute of TechnologyWuhan 430205China Hubei Three Gorges Laboratory Yichang 443008China

A hierarchical reduced graphene oxide-MnO_(2)@polypyrrole coaxial nanotube composite hydrogel was prepared via oxidative polymerization of pyrrole in the presence of MnO_(2)nanotubes,followed by the hydrothermal treatment of graphene oxide and MnO_(2)@polypyrrole coaxial *** stable composite hydrogel with a hierarchical network was composed of one-dimensional MnO_(2)@polypyrrole coaxial nanotube and two-dimensional graphene nanosheet and characterized by scanning electron microscope,Fourier transform infrared spectroscopy,X-ray diffraction,Brunauer-Emmett-Teller surface,and X-ray photoelectron spectroscopy *** composite hydrogel can be used as an efficient adsorbent for Cr(Ⅵ)removal due to the synergistic interaction between graphene and MnO_(2)@polypyrrole and the hierarchical structure of the ***,the composite hydrogel is easily separated because of its stable monolith,and it is reusable(76.8%of removal ability remaining after five adsorption-desorption cycles).The simple fabrication and cost-effective separation process together with the excellent absorption performance endow the composite hydrogel with great potential for practical wastewater treatment.

关键词： hydrogel polypyrrole MnO_(2) graphene Cr(Ⅵ)removal

Triple the steady-state reaction rate by decorating the In_(2)O_(3)surface with SiO_(x)for CO_(2)hydrogenation

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Journal of Energy Chemistry 2024年第8期95卷 96-105,I0003页

作者： Hao Wang Chun Yang Xiaoyan Yu Mingrui Wang Runze Yang Xiaowa Nie ben Hang Yin Alex C.K.Yip Chunshan song Guanghui Zhang Xinwen Guo State Key Laboratory of Fine Chemicals Frontier Science Center for Smart MaterialsPSU-DUT Joint Center for Energy ResearchSchool of Chemical EngineeringDalian University of TechnologyDalian 116024LiaoningChina Department of Chemistry the Chinese University of Hong KongHong Kong 999077China Paihau-Robinson Research Institute the MacDiarmid Institute for Advanced Materials and NanotechnologyVictoria University of WellingtonWellington 6012New Zealand Department of Chemical and Process Engineering The University of CanterburyChristchurch 8041New Zealand

Indium oxide(In_(2)O_(3)),as a promising candidate for CO_(2)hydrogenation to C_(1) products,often suffers from sintering and activity decline,closely related to the undesirable structural evolution under reaction *** on the comprehension of the dynamic evolution,this study presents an efficient strategy to alleviate the agglomeration of In_(2)O_(3)nanoparticles by the surface decoration with highly dispersed silica species(SiO_(x)).Various structural characterizations combined with density functional theory calculations demonstrated that the sintering resulted from the over-reduction,while the enhanced stability originated from the anchoring effect of highly stable In-OSi bonds,which hinders the substantial formation of metallic In(In^(0))and the subsequent agglomeration.0.6Si/In_(2)O_(3)exhibited CO_(2)conversion rate of10.0 mmol g^(-1)h^(-1)at steady state vs.3.5 mmol g^(-1)h^(-1)on In_(2)O_(3)in CO_(2)*** steady-state activity was also achieved on Pd-modified *** to the traditional Pd/In_(2)O_(3)catalyst,the methanol production rate of Pd catalyst supported on 0.6Si/In_(2)O_(3)was enhanced by 23%,showing the potential of In_(2)O_(3)modified by SiO_(x)in serving as a platform *** work provides a promising method to design new In_(2)O_(3)-based catalysts with improved activity and stability in CO_(2)hydrogenation.

关键词： CO_(2)hydrogenation In_(2)O_(3)sintering Dynamic structural evolution Surface SiO_(x)modification DFT simulations

The Persistence and Zonal Scale of Atmospheric Dipolar Modes

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Advances in Atmospheric Sciences 2024年第3期41卷 478-492页

作者： Jie song State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics(LASG) Institute of Atmospheric Physics(IAP)Chinese Academy of SciencesBeijing 100029China

This study investigates the relationship between the persistence and the zonal scale of atmospheric dipolar modes(DMs). Results from the daily data of ERA5 and the long-term output of an idealized atmospheric model show that the atmospheric DMs with a broader(narrower) zonal scale dipolar structure possess a longer(shorter) persistence. A detailed vorticity budget analysis indicates that the persistence of a hemispheric-scale DM(1/1 DM) and a regional or sectoral DM(1/8 DM) in the model both largely rely on the persistence of the nonlinear eddy forcing. Linear terms can indirectly reduce the persistence of the anomalous nonlinear eddy forcing in a 1/8 DM by modifying the baroclinicity via the arousal of anomalous vertical motions. Therefore, the atmospheric DMs with a broader(narrower) zonal scale possess a longer(shorter) persistence because the effects of the linear terms are less(more) pronounced when the atmospheric DMs have better(worse) zonal symmetry. Further analyses show that the positive eddy feedback effect is weak or even absent in a 1/8DM and the high-frequency eddy forcing acts more like a concomitant phenomenon rather than a leading driving factor for a 1/8 DM. Thus, the hemispheric-scale DM and the regional or sectoral DMs are different, not only in their persistence but also in their dynamics.

关键词： NAM NAO eddy feedback persistence linear term