检索结果-南通市图书馆

Solid particle size characterization by a high-frequency collision response in pneumatic particulate flow

在线全文

学校读者我要写书评

暂无评论

Particuology 2024年第3期86卷 39-54页

作者： kai wang yichen li Ziang Chang Min Qin Guangming Fu Bangtang yin Gang wang jiaqi Tian School of Petroleum Engineering China University of Petroleum(East China)Qingdao266580China Key Laboratory of Unconventional Oil&Gas Development China University of Petroleum(East China)Ministry of EducationQingdao266580China National Engineering Research Center of Oil&Gas Drilling and Completion Technology Qingdao266580China Shock and Vibration of Engineering Materials and Structures Key Lab ofSichuan Province Southwest University of Science and TechnologyMianyang621000China

A novel triaxial vibration method is developed for the real-time characterization of the solid particle size distribution(PsD)in pneumatic particulate flow,which is critical for chemical *** this work,the particle-wall collision and friction behaviours were analysed by the time-domain statistical and timefrequency joint methods to narrow the high-frequency response range by the initial experiment of free fall for a single particle,interparticle,and multiple ***,verification experiments of PSD characterization in pneumatic flow were ***,the quantitative triaxial energy response model that considers the particle size,shape,and mass factors were ***,a good agreement of the particle number identification was found between the triaxial vibration energy and mean particle size of 150-550μ***,the performance with the best accuracy was focused on a range of 42-43 kHz in the x-axis and z-axis and 36.8-38.8 kHz in the ***,the individual particle energy was inversely analysed by the triaxial vibration response within the optimized frequency bands,and the PSD was characterized in real-time by a low error rate,that is,5.2% from the XZ-axis direction of sand(42-43 kHz)and 5.6% from the XYZ-axis of glass(30.9-33.9 kHz,46.2-47.2 kHz,38.3-41.3 kHz for each axis response).Therefore,this research complements the existing approaches for PsD characterization in particulate multiphase flow.

关键词： Solid particulate flow Triaxial vibration High-frequency response Particle wall Particle size distribution

Achieving high carrier mobility and low lattice thermal conductivity in GeTe-based alloys by cationic/anionic co-doping

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rare Metals 2024年第6期43卷 2784-2795页

作者： Xiao-Qiang wang Xiao-Quan Hu Jun-Yan lin Chu-Bin li Xiao-Tong Yu Qi-Yong Chen li-li Xi Qi-Shuo Yang Han li ji-Ye Zhang Shuan-Kui li kai Guo School of Physics and Materials Science Guangzhou UniversityGuangzhou 510006China Research Center for Advanced Information Materials(CAIM) Huangpu Research&Graduate School of Guangzhou UniversitySino-Singapore Guangzhou Knowledge CityGuangzhou510555China School of Materials Science and Engineering Shanghai UniversityShanghai 200444China Materials Genome Institute Shanghai UniversityShanghai 200444China School of Mechanical and Mining Engineering University of QueenslandBrisbaneQLD 4072Australia Key Laboratory of Si-Based Information Materials&Devices and Integrated Circuits Design Department of Education of Guangdong ProvinceGuangzhou 510006China

TheⅣ-Ⅵcompound GeTe is considered as a promising alternative to the toxic PbTe for high-efficiency mid-temperature thermoelectric ***,pristine GeTe suffers from a high concentration of Ge vacancies,resulting in an excessively high hole concentration(>1×10^(21)cm^(-3)),which greatly limits its thermoelectric *** address this issue,CuBiTe_(2)alloying is introduced to increase the formation energy of Ge vacancies in GeTe,thereby inhibiting the high carrier *** carrier scattering caused by the electronegativity difference between different elements is suppressed due to the similar electronegativity of Cu and Ge atoms.A relatively high hole mobility is obtained,which ultimately leads to a high power ***,by introducing Se as an alloying element at the anionic site in GeTe,dense point defects with mass/strainfield fluctuations are *** contributes to the strengthening of phonon scattering,thereby reducing the lattice thermal conductivity from 1.44 W·m^(-1)·K^(-1)for pristine GeTe to 0.28 W·m^(-1)·K^(-1)for Ge_(0.95)Cu_(0.05)Bi_(0.05)Te_(0.9)Se_(0.15)compound at 623 K.

关键词： GeTe Carrier mobility CuBiTe_(2)alloying Lattice thermal conductivity Thermoelectric properties

Sn-decorated CeO_(2) with different morphologies for direct dehydrogenation of ethylbenzene

在线全文

学校读者我要写书评

暂无评论

Journal of Rare Earths 2024年第1期42卷 102-109,I0004页

作者： kai Zhang Guoju Cui Mengzhen Yuan Huiwen Huang Ning li jiale Xu Guowei wang Chunyi li State Key Laboratory of Heavy Oil Processing China University of Petroleum(East China)Qingdao266580China Petrochemical Plant of Sinopec Shengli Oilfield Company Dongying257237China College of Chemical and Biological Engineering Shandong University of Science and TechnologyQingdao266590China

Three Sn-decorated ceria catalysts with various morphologies(rods,particles,and cubes)were prepared and applied to the direct dehydrogenation of ***-technology characterizations,including X-ray photoelectro n spectroscopy(XPS),H_(2)-tempe rature programmed reduction(H_(2)-TPR),and Raman spectroscopy,prove that the oxygen vacancies are the active sites for ethylbenzene dehydrogenation,which can be regulated by engineering CeO_(2) morphology and enhanced via introducing metal *** the results of activity test,the catalytic activities for ethylbenzene dehydrogenation over different samples are closely dependent on the amount of oxygen *** reduced Sn-decorated CeO_(2) catalyst with nanoparticles morphology exhibits better dehydrogenation performance than the other two studied catalysts at 600℃.This work provides an effective approach to regulate the active oxygen vacancies and further enhance the dehydrogenation activities through engineering the surface morphology of the catalyst and introducing suitable additives.

关键词： Ethylbenzene dehydrogenation CeO_(2) Sn Morphology Oxygen vacancy Rare earths

Simulation of the L-valve in the circulating fluidized bed with a coarse-grained discrete particle method

在线全文

学校读者我要写书评

暂无评论

Particuology 2024年第7期90卷 266-280页

作者： Ruixiang Tang Zheng Zou ji Xu Junwu wang Qingshan Zhu Hongzhong li State Key Laboratory of Mesoscience and Engineering Institute of Process EngineeringChinese Academy of SciencesP.O.Box 353Beijing100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing100049China Innovation Academy for Green Manufacture Chinese Academy of SciencesBeijing100190China

Stable and controllable solid flow is essential in circulating fluidized bed (CFB) systems. The L-valve is a typical non-mechanical valve that can provide flexible solid feeding. The investigation of the solid circulation rate and the hydrodynamic characteristics of the L-valve is crucial to its design and operation. The gas-solid flow in the L-valve of a full-loop CFB is studied with the coarse-grained discrete particle method (EMMS-DPM). Good agreements on the solid circulation rate and the pressure drop through the L-valve are achieved between the simulated and experimental data. The solid circulation rate increases linearly with the aeration velocity until the stable particle circulation of the CFB is destroyed. The flow patterns in the horizontal section of L-valve are gas-solid slug flow above the stationary solid layer and the moving solid layer, respectively. The effects of L-valve geometric parameters on the solid flow characteristics are also investigated. The results indicate that reducing the diameter and length of the horizontal section of L-valve can improve the solid transport efficiency, especially at low aeration velocity. Besides, the solid conveying capacity and flow stability are improved when the sharp bend of L-valve is modified to be a gradual bend.

关键词： L-valve Circulating fluidized bed Full loop Discrete particle method Gas-solid flow

Crystal phase control and ignition properties of HNS/CL-20 composite microspheres prepared by microfluidics combined with emulsification techniques

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Particuology 2024年第2期85卷 241-251页

作者： yi liu Yunyan Guo Rui Zhu jinqiang Zhou Zhengxu lin kai Han Chongwei An jingyu wang Bidong Wu School of Environment and Safety Engineering North University of ChinaTaiyuan030051China School of Engineering Beijing Institute of TechnologyBeijing100081China Shanxi Province Ultrafine Powder Engineering Technology Research Center Taiyuan030051China

Improved controllability and energy density of ignition agents are of great significance for the devel-opment of energetic composite *** this study,droplet microfluidics and emulsification tech-niques were combined to prepare HNS/CL-20 composite microspheres with polyglycidyl azide polymer(GAP)as the *** influence of binder content on the morphology of microspheres was investi-gated,and the microspheres were characterized and tested for particle size,crystal structure,thermal decomposition,dispersibility,mechanical sensitivity,combustion behavior and detonation *** results showed that microspheres prepared with a binder content of 3%had higher sphericity and particle size *** microspheres retained the crystal structure of both HNS and CL-20(ε-type).Compared with raw HNS,the microspheres had higher apparent activation energy,better safety per-formance,and good *** ignition experiments and detonation performance tests show that HNS/CL-20 composite microspheres have excellent ignition performance,obvious combustion flame,and significant energy release effects,which are expected to achieve high energy and high-speed response of the igniter,thus improving the ignition reliability in special environments or systems.

关键词： Droplet microfluidics Emulsification technology Energetic materials Composite microspheres Crystal phase control Ignition

Investigating effect of coke porosity on blast furnace performance based on multi-physical fields

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research(International) 2024年第2期31卷 357-367页

作者： ji Chen Zhao Lei Zhe Yao li wang Qiang ling Ping Cui Anhui Province Key Laboratory of Coal Clean Conversion and High Valued Utilization School of Chemistry and Chemical EngineeringAnhui University of TechnologyMa’anshan243002AnhuiChina Shanxi Academy of Printing Technology Research Institute Co. Ltd.Xi’an710077ShaanxiChina

Reducing coke use is an effective measure to reduce carbon emission and energy consumption in the blast furnace(BF)***,BF is a high-temperature moving bed reactor,where complex physical transformations coupled with complicated reactions *** makes it challenging to investigate the factors determining BF performance with the conventional method.A multi-physical field coupling mathematical model of BF was thus developed to describe its mass and heat transfer as well as its intrinsic ***,the proposed model was validated with the production *** coupling conditions,influences of dominating reactions on BF performance(temperature distribution,gas distribution,iron formation reaction,and direct reduction degree)were *** results indicated that coke combustion,indirect reduction,and direct reduction of iron ore mainly took place nearby the shaft tuyere,cohesive zone,and dripping zone,***,the rate of coke solution loss reaction was increased with the rising coke porosity in the cohesive *** the effect of coke porosity on the efficiency and stability of BF,the coke porosity of 0.42 was regarded as a reasonable value.

关键词： Blast furnace Mathematical model Multi-physical field Simulation Coke porosity

Adaptive state-constrained/model-free iterative sliding mode control for aerial robot trajectory tracking

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2024年第4期45卷 603-618页

作者： Chen AN jiaxi ZHOU kai wang College of Mechanical and Vehicle Engineering Hunan UniversityChangsha 410082China Department of Mechanical Engineering The Hong Kong Polytechnic UniversityHong KongChina

This paper develops a novel hierarchical control strategy for improving the trajectory tracking capability of aerial robots under parameter *** hierarchical control strategy is composed of an adaptive sliding mode controller and a model-free iterative sliding mode controller(MFISMC).A position controller is designed based on adaptive sliding mode control(SMC)to safely drive the aerial robot and ensure fast state convergence under external ***,the MFISMC acts as an attitude controller to estimate the unmodeled dynamics without detailed knowledge of aerial ***,the adaption laws are derived with the Lyapunov theory to guarantee the asymptotic tracking of the system ***,to demonstrate the performance and robustness of the proposed control strategy,numerical simulations are carried out,which are also compared with other conventional strategies,such as proportional-integralderivative(PID),backstepping(BS),and *** simulation results indicate that the proposed hierarchical control strategy can fulfill zero steady-state error and achieve faster convergence compared with conventional strategies.

关键词： aerial robot hierarchical control strategy model-free iterative sliding mode controller(MFISMC) trajectory tracking reinforcement learning

Upcycling electroplating sludge into bioengineering-enabled highly stable dual-site Fe-Ni_(2)P@C electrocatalysts for efficient oxygen evolution

在线全文

学校读者我要写书评

暂无评论

Nano Research 2024年第8期17卷 6984-6992页

作者： jiawen liu Zunpeng Zuo Feng Gao kai yi jiahui lin Mengye wang Zhang lin Feng Huang State Key Laboratory of Optoelectronic Materials and Technologies School of MaterialsSun Yat-Sen UniversityGuangzhou 510275China Department of Chemistry City University of Hong KongHong Kong 999077China School of Metallurgy and Environment Central South UniversityChangsha 410083China Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou 341000China

The advancement of bimetallic catalysts holds significant promise for the innovation of oxygen evolution reaction(OER)*** from adsorbate evolution mechanism(AEM)and lattice oxygen oxidation mechanism(LOM),the incorporation of dual active sites has the potential to foster novel OER pathways,such as the coupled oxygen evolution mechanism(COM),which can surpass the limitations of OER and elevate catalytic *** this study,uniformly distributed Fe/Ni dual-site Fe-Ni_(2)P@C electrocatalysts are crafted by upcycling metals in electroplating sludge via an eco-friendly and sustainable microbial engineering *** findings indicate that a substantial number of defects emerge at the Ni2P crystal during the OER process,laying the groundwork for lattice oxygen ***,the displacement of Ni/Fe in the crystal lattice intensifies the asymmetry of the electronic structure at the metal active sites,facilitating the deprotonation *** research introduces an innovative paradigm for the synthesis of effective and robust transition metal-based OER catalysts,with implications for sustainable energy generation technologies.

关键词： oxygen evolution reaction dual active sites adsorbate evolution mechanism lattice oxygen mechanism bioengineering

6DOF pose estimation of a 3D rigid object based on edge-enhanced point pair features

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computational Visual Media 2024年第1期10卷 61-77页

作者： Chenyi liu Fei Chen Lu Deng Renjiao yi lintao Zheng Chenyang Zhu jia wang kai Xu College of Computing National University of Defense TechnologyChangsha410073China Department of Spine Surgery the Second Xiangya HospitalCentral South UniversityChangsha410011China Clinical Nursing Teaching and Research Section the Second Xiangya HospitalChangsha410011China College of Meteorology and Oceanography National University of Defense TechnologyChangsha410073China Beijing Institute of Tracking and Communication Technology Beijing100094China

The point pair feature(PPF)is widely used for 6D pose *** this paper,we propose an efficient 6D pose estimation method based on the PPF *** introduce a well-targeted down-sampling strategy that focuses on edge areas for efficient feature extraction for complex geometry.A pose hypothesis validation approach is proposed to resolve ambiguity due to symmetry by calculating the edge matching *** perform evaluations on two challenging datasets and one real-world collected dataset,demonstrating the superiority of our method for pose estimation for geometrically complex,occluded,symmetrical *** further validate our method by applying it to simulated punctures.

关键词： point pair feature(PPF) pose estimation object recognition 3D point cloud