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Particuology 2024年第6期89卷 88-98页

作者： Ming Liu Guoqiang Shao Pengpeng lv Jun Li Qingshan Zhu State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China

Two critical parameters:Glossiness and chromaticity space of pearlescent pigments were evaluated based on crystallinity and grain *** the roughness and the vertical distance evolution along the surface of deposited TiO_(2)film are affected by the *** optimal crystallinity of TiO_(2)was deposited at the temperature of 350℃.The TiCl4 concentration effectively changed the grain ***,the high flow rate of fluidizing gas and optimal gas–solid ratio(ling the film thickness based on TiO_(2)***,the silver pearlescent pigment with high glossiness was prepared by chemical vapor deposition method in a fluidized bed reactor.

关键词： Fluidized bed chemical vapor deposition TiO_(2)film deposition Pearlescent pigment Free powder restrain Crystal growth

Numerical simulation of granular silicon growth and silicon fines formation process in polysilicon fluidized bed

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Particuology 2024年第4期87卷 74-86页

作者： Guangkai Gu Guoqiang lv Wenhui Ma Shanlin Du Boqiang Fu Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming 650093China State Key Laboratory of Complex Nonferrous Metal Resources Cleaning Utilization in Yunnan Province Kunming 650093China

Operating conditions strongly affect the yield and quality of polysilicon in a polysilicon fluidized *** this study,a new model of polysilicon fluidized bed was established using the Euler-Euler model coupled with population balance model(PBM),which was combined with fluid flow,heat,and mass transfer models,while considering the scavenging effect of silicon *** effects of different operating conditions on the deposition and formation rates of silicon fines were *** show that the model can correctly describe the particle growth process in the fluidized bed of *** silicon fines and the interphase velocity difference show"N"-and"M"-shaped distributions along the axial direction,*** particle temperature and concentration near the wall are higher than those in the central *** decomposition of silane in the bottom region of the bed is dominated by het-erogeneous *** scavenging of silicon fines occurs in the dilute-phase *** effects of operating conditions,*** gas temperature,silane composition,and gas velocity,on the reactor performance were also explored *** the inlet gas composition and velocity enhances the formation rates of solid silicon and *** the inlet gas temperature promotes the growth of solid silicon and inhibits the formation of silicon *** fluidization ratio,low inlet silane concentration,and high inlet gas temperature enhance the selectivity of silicon growth.

关键词： Polysilicon fluidized bed Particle growth Fines CFD Population balance model(PBM)

Monophase-homointerface electrodes intrinsically stabilize high-voltage all-solid-state batteries

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Science China Chemistry 2024年第5期67卷 1729-1739页

作者： Xiaolin Xiong Xianguo Ma Tianshi lv Liquan Chen Liumin Suo Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of ScienceBeijing 100190China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China

The electrochemical stability and contact reliability of heterointerfaces between the solid electrolyte(SE) and electrode are critical for all-solid-state batteries(ASSBs), particularly much more challenging for high-voltage ASSBs, owing to the limited thermodynamically electrochemical window and mechanical inflexibility of SE, aggravating interfacial side reactions and contact failure. Considering all those issues originating from intrinsic heterogeneity in physicochemical features between the cathode material and SE, we are thinking about simplifying the heterointerfaces into a homointerface as a permanent cure to solve all electrochemical-mechanical interfacial failure. Herein, we propose monophase cathodes to construct thermodynamically stable all-in-one homointerfaces in ASS electrodes, removing unstable heterointerfaces by excluding SEs and intrinsically eliminating the Li chemical potential gap to avoid the formation of lithium-depleted space-charge layer and highly resistive mixed ion–electron conductor interphase. Our conception is successfully validated in the layered transition-metal oxide cathodes, which display outstanding stability no matter the MH-LiCoO_(2) cathode charging to 4.7 V or MH-Li_(1.2)Mn_(0.54)Ni_(0.13)-Co_(0.13)O_(2) cathode charging to 5.3 V. It is undeniable that our current version of above-illustrated MH-cathodes would bring out some new challenges for the practical application due to abandoning the SE. However, we believe our work also offers a brandnew direction to ultimately address the electrochemical–mechanical interfacial issues that would be promising for high-energy ASSBs with more discoveries of advanced monophase cathodes in the future.

关键词： monophase-homointerface electrode high-voltage all-solid-state batteries electrochemical-mechanical interfacial issue

Digital twin driven and intelligence enabled content delivery in end-edge-cloud collaborative 5G networks

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Digital Communications and Networks 2024年第2期10卷 328-336页

作者： Bo Yi Jianhui lv Xingwei Wang Lianbo Ma Min Huang College of Computer Science and Engineering Northeastern UniversityShenyang110169China Pengcheng Lab. Shenzhen518055China College of Software Northeastern UniversityShenyang110819China College of Information Science and Engineering Northeastern UniversityShenyang110819China

The rapid development of 5G/6G and AI enables an environment of Internet of Everything(IoE)which can support millions of connected mobile devices and applications to operate smoothly at high speed and low ***,these massive devices will lead to explosive traffic growth,which in turn cause great burden for the data transmission and content *** challenge can be eased by sinking some critical content from cloud to *** this case,how to determine the critical content,where to sink and how to access the content correctly and efficiently become new *** work focuses on establishing a highly efficient content delivery framework in the IoE *** particular,the IoE environment is re-constructed as an end-edge-cloud collaborative system,in which the concept of digital twin is applied to promote the *** on the digital asset obtained by digital twin from end users,a content popularity prediction scheme is firstly proposed to decide the critical content by using the Temporal Pattern Attention(TPA)enabled Long Short-Term Memory(LSTM)***,the prediction results are input for the proposed caching scheme to decide where to sink the critical content by using the Reinforce Learning(RL)***,a collaborative routing scheme is proposed to determine the way to access the content with the objective of minimizing *** experimental results indicate that the proposed schemes outperform the state-of-the-art benchmarks in terms of the caching hit rate,the average throughput,the successful content delivery rate and the average routing overhead.

关键词： Digital twin IoE Content delivery Caching Routing

A Hybrid Integrated and Low-Cost Multi-Chip Broadband Doherty Power Amplifier Module for 5G Massive MIMO Application

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Engineering 2024年第7期38卷 223-232页

作者： Fei Huang Guansheng lv Huibo Wu Wenhua Chen Zhenghe Feng Department of Electronic Engineering Tsinghua UniversityBeijing 100084China

In this paper,a hybrid integrated broadband Doherty power amplifier(DPA)based on a multi-chip module(MCM),whose active devices are fabricated using the gallium nitride(GaN)process and whose passive circuits are fabricated using the gallium arsenide(GaAs)integrated passive device(IPD)process,is proposed for 5G massive multiple-input multiple-output(MIMO)*** inverted DPA structure with a low-Q output network is proposed to achieve better bandwidth performance,and a single-driver architecture is adopted for a chip with high gain and small *** proposed DPA has a bandwidth of 4.4-5.0 GHz that can achieve a saturation of more than 45.0 *** gain compression from 37 dBm to saturation power is less than 4 dB,and the average power-added efficiency(PAE)is 36.3%with an 8.5 dB peak-to-average power ratio(PAPR)in 4.5-5.0 *** measured adjacent channel power ratio(ACPR)is better than50 dBc after digital predistortion(DPD),exhibiting satisfactory linearity.

关键词： 5G Doherty power amplifier Multi-input multi-output Multi-chip modules Hybrid integrated

Laminar Flame Instability of n-Hexane,n-Octane,and n-Decane in Spherical Expanding Flames

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Journal of Thermal Science 2024年第3期33卷 1189-1199页

作者： YIN Geyuan HU Erjiang LI Xiaotian lv Xin HUANG Zuohua State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi’an710049China United Automotive Electronic Systems Co. LtdShanghai201206China Chongqing Changan Automobile Co. Ltd.Chongqing401120China

This paper focuses on the laminar flame instability of three high molecular weight n-alkanes,namely n-hexane,n-octane,and *** experiment was carried out in a constant volume combustion bomb to get the flame *** critical radius under different conditions was extracted using the image processing *** with the existing critical Peclet number theory,the dominant factors of flame instability under current conditions for three n-alkanes can be figured ***,the average cell size(equivalent cell radius,R_(cell))was extracted to provide quantitative analysis of the flame cellular structure,based on the method developed in this *** theoretical R_(cell)were also calculated and compared with the experimental results to validate the proposed method.

关键词： cellular instability equivalent cell radius critical Peclet number spherical flame

An air combat maneuver pattern extraction based on time series segmentation and clustering analysis

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Defence Technology（防务技术） 2024年第6期36卷 149-162页

作者： Zhifei Xi Yingxin Kou Zhanwu Li Yue lv You Li Air Force Engineering University No.1 Baling RoadBaqiao DistrictXi'anShaanxi ProvinceChina

Target maneuver recognition is a prerequisite for air combat situation awareness,trajectory prediction,threat assessment and maneuver *** get rid of the dependence of the current target maneuver recognition method on empirical criteria and sample data,and automatically and adaptively complete the task of extracting the target maneuver pattern,in this paper,an air combat maneuver pattern extraction based on time series segmentation and clustering analysis is proposed by combining autoencoder,G-G clustering algorithm and the selective ensemble clustering analysis ***,the autoencoder is used to extract key features of maneuvering trajectory to remove the impacts of redundant variables and reduce the data dimension;Then,taking the time information into account,the segmentation of Maneuver characteristic time series is realized with the improved FSTS-AEGG algorithm,and a large number of maneuver primitives are extracted;Finally,the maneuver primitives are grouped into some categories by using the selective ensemble multiple time series clustering algorithm,which can prove that each class represents a maneuver *** maneuver pattern extraction method is applied to small scale air combat trajectory and can recognize and correctly partition at least 71.3%of maneuver actions,indicating that the method is effective and satisfies the requirements for engineering *** addition,this method can provide data support for various target maneuvering recognition methods proposed in the literature,greatly reduce the workload and improve the recognition accuracy.

关键词： Maneuver pattern extraction Data mining Fuzzy segmentation Selective ensemble clustering

Longitudinal vibration characteristics of a tapered pipe pile considering the vertical support of surrounding soil and construction disturbance

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Earthquake Engineering and Engineering Vibration 2024年第1期23卷 51-63页

作者： Li Zhenya Pan Yunchao He Xianbin lv Chong Mohammad Towhid Key Laboratory of Ministry of Education for Geomechanics and Embankment Engineering Hohai UniversityNanjing 210098China Geotechnical Research Institute Hohai UniversityNanjing 210098China MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering Zhejiang UniversityHangzhou 310058China

This research is concentrated on the longitudinal vibration of a tapered pipe pile considering the vertical support of the surrounding soil and construction ***,the pile-soil system is partitioned into finite segments in the vertical direction and the Voigt model is applied to simulate the vertical support of the surrounding soil acting on the pile *** surrounding soil is divided into finite ring-shaped zones in the radial direction to consider the construction ***,the shear complex stiffness at the pile-soil interface is derived by solving the dynamic equilibrium equation for the soil from the outermost to innermost *** displacement impedance at the top of an arbitrary pile segment is obtained by solving the dynamic equilibrium equation for the pile and is combined with the vertical support of the surrounding soil to derive the displacement impedance at the bottom of the upper adjacent ***,the displacement impedance at the pile head is obtained based on the impedance function transfer ***,the reliability of the proposed solution is verified,followed by a sensitivity analysis concerning the coupling effect of the pile parameters,construction disturbance and the vertical support of the surrounding soil on the displacement impedance of the pile.

关键词： tapered pipe pile longitudinal vibration vertical support of the surrounding soil construction disturbance displacement impedance

Area Operators on Bergman Spaces

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Acta Mathematica Sinica,English Series 2024年第5期40卷 1161-1176页

作者： Xiao Fen lv Jordi PAU Mao Fa WANG Department of Mathematics Huzhou UniversityHuzhou 313000P.R.China Departament de Matemàtiques i Informàtica Universitat de Barcelona08007 BarcelonaCataloniaSpain School of Mathematics and Statistics Wuhan UniversityWuhan 430072P.R.China

We completely characterize the boundedness of area operators from the Bergman spaces A_(α)^(p)(Bn)to the Lebesgue spaces L^(q)(S_(n))for all 0 详细信息

We completely characterize the boundedness of area operators from the Bergman spaces A_(α)^(p)(Bn)to the Lebesgue spaces L^(q)(S_(n))for all 0lve the cases left open there and extend the results to n-complex dimension.

关键词： Area operator Bergman space tent space area formula

A brief review of tribological properties for black phosphorus

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Friction 2024年第5期12卷 823-844页

作者： Fanfan lv Wei WANG Jinjin LI Yuan GAO Kuaishe WANG College of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an710055China State Key Laboratory of Tribology in Advanced Equipment Tsinghua UniversityBeijing10084China

Black phosphorus (BP) is a new class of two-dimensional (2D) layered material, which shows the unanticipated characteristics in many aspects including electronics, transistors, sensors, energy storage, batteries, photocatalysis, and other applications due to its high charge carrier mobility, tunable direct bandgap, and unique in-plane anisotropic structure. In addition, BP has drawn tremendous attention in the field of tribology due to the low shear strength, the layered structure, and the weak connected force between the layers by van der Waals interaction. In recent years, many significant progresses have been made in experimental studies on BP materials as solid lubricants or lubrication additives. This work offers a review of researching regarding the tribological properties of BP. Moreover, the lubrication mechanisms of BP as the lubrication additive including the formation of the tribo-film, micro-bearing effect, and self-repair performance are also summarized. Finally, the current challenges and prospects of BP material as lubricant are proposed.

关键词： black phosphorus(BP) two-dimensional(2D)layered material lubrication additives tribological mechanisms