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Coupling interface constructions of hollow Co-Mo mixed multiple oxidation states heterostructure for high-performance aprotic Li-O_(2) battery

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nano Research 2024年第5期17卷 4100-4107页

作者： Xingzi zheng Mengwei Yuan Jingshen Xu Zihan Li Caiyun nan Genban Sun Beijing Key Laboratory of Energy Conversion and Storage Materials College of ChemistryBeijing Normal UniversityBeijing 100875China Center for Advanced Materials Research Beijing Normal UniversityZhuhai 519087China

Constructing interfaces in heterostructures is effective for modulating the electronic properties of *** hollow CoMoO_(4)-Co_(3)O_(4) heterostructure(HCMCH)was prepared as a bifunctional electrocatalyst for Li-O_(2) *** different components in CoMoO_(4)-Co_(3)O_(4) heterostructure presented the efficient coupling and enhanced the electrocatalytic activity for aprotic oxygen reduction reaction(ORR)and oxygen evolution reaction(OER),in which it improved the obviously reduced overpotential of 300 mV(compared with the pure Ketjen black(KB)electrode),enhanced reversibility of 80%capacity retention after 6 full cycles and the superior cyclability of more than 200 cycles with an optimized *** battery performance of the HCMCH was not only associated with the unique hollow structure and rich active sites but also with coupling interface constructions synergetic effects attaching to the improving conductivity and optimized the discharge *** results suggested that this HCMCH electrocatalyst was a promising candidate for the Li-O_(2) battery and it gave a novel insight for high performance electrocatalyst designing.

关键词： Li-oxygen battery heterostructure electrocatalyst coupling interface

A Quick Calculation Method for Radiation Pattern of Submillimeter Telescope with Deformation and Displacement

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Research in Astronomy and Astrophysics 2024年第3期24卷 249-265页

作者： Jia You yi-Wei Yao zheng Wang School of Automation Southeast UniversityNanjing 210096China

Radiation pattern captures the electromagnetic performance of reflector antennas,which is significantly affected by the deformation of the primary reflector due to gravity and the displacement of the secondary *** the design process of large reflector antennas,a substantial amount of time is often dedicated to iteratively adjusting structural parameters and validating electromagnetic *** improve the efficiency of the design process,we first propose an approximate calculation method of optical path difference(OPD)for the deformation of the primary reflector under gravity and the displacement of the secondary *** an OPD fitting function based on the modified Zernike polynomials is proposed to capture the phase difference of radiation over the aperture plane,based on which the radiation pattern will be obtained quickly by the aperture field integration *** experiments demonstrate the effectiveness of the proposed quick calculation method for analyzing the radiation pattern of a 10.4 m submillimeter telescope antenna at its highest operating frequency of 856 *** comparison with the numerical simulation method based on GRASP(which is an antenna electromagnetic analysis tool combining physical optics(PO)and physical theory of diffraction(PTD)),the quick calculation method reduces the time for radiation pattern analysis from more than one hour to less than two ***,the quick calculation method exhibits excellent accuracy for the figure of merit(FOM)of the radiation ***,the proposed quick calculation method can obtain the radiation pattern with high speed and *** to the time-consuming numerical simulation method(PO and PTD),it can be employed for quick analysis of the radiation pattern for the lateral displacement of the secondary reflector and the deformation of the primary reflector under gravity in the design process of a reflector antenna.

关键词： instrumentation high angular resolution-methods data analysis-methods analytical

Clinical observation on 90 cases of primary dysmenorrhea treated by buccal acupuncture therapy:a randomized controlled study

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Journal of Traditional Chinese Medicine 2024年第1期44卷 172-181页

作者： YANG yi YE Huijun zheng Huiling JIN Lihua Department of Obstetrics and Gynecology the Second Affiliated Hospital of Zhejiang Chinese Medical UniversityXinhua Hospital of Zhejiang ProvinceHangzhou 310005China

OBJECTIVE:To explore the short-term and long-term efficacy of buccal acupuncture therapy in the treatment of patients with primary dysmenorrhea(PD).METHODS:A total of 90 patients with PD who were admitted to the Second Affiliated Hospital of Zhejiang University of Traditional Chinese Medicine from January 2020 to December 2021 were included in this study and randomly divided into three groups,including the observation group,the control group,and the placebo group,with 30 patients in each *** in the observation group were treated according to the syndrome types of Traditional Chinese Medicine,those in the control group were treated with Saridon,and those in the placebo group received a *** visual analog scale(VAS)scores of these patients were evaluated at different time points(before treatment,5 min after needle retention,30 min after needle retention,1 h after treatment,2 h after treatment,1 d after treatment,and 2 d after treatment).The Cox Menstrual Symptom Scale(CMSS)scores were assessed before the treatment and after three courses of ***,these two scales were also evaluated during ***,the pain score and adverse reactions of these patients were assessed during ***:After treatment,the VAS and CMSS scores in the observation group decreased significantly(P<0.05)5 and 30 min after needle retention and after ***:Buccal acupuncture therapy is verified to have short-term efficacy in the treatment of *** addition,this therapy has an immediate analgesic effect and long-term efficacy in reducing the severity and frequency of PD.

关键词： buccal acupuncture therapy primary dysmenorrhea pain score randomized controlled trial

Effect mechanism of seepage force on the hydraulic fracture propagation

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International Journal of Coal Science & Technology 2024年第3期11卷 223-240页

作者： Haiyang Wang Desheng Zhou yi Zou Peng zheng School of Petroleum Engineering Xi’an Shiyou UniversityXi’an710065China Engineering Research Center of Development and Management for Low to Extra-Low Permeability Oil and Gas Reservoirs in West China Ministry of EducationXi’an Shiyou UniversityXi’an710065ShaanxiChina Xi’an University of Science and Technology Xi’an710054ShaanxiChina

The flow of fluid through the porous matrix of a reservoir rock applies a seepage force to the solid rock *** the seepage force exerted by fluid flow through the porous matrix of a reservoir rock has a notable influence on rock deformation and failure,its effect on hydraulic fracture(HF)propagation remains ***,in this study,we improved a traditional fluid–solid coupling method by incorporating the role of seepage force during the fracturing fluid seepage,using the discrete element ***,we validated the simulation results of the improved method by comparing them with an analytical solution of the seepage force and published experimental ***,we conducted numerical simulations in both homogeneous and heterogeneous sandstone formations to investigate the influence of seepage force on HF *** results indicate that fluid viscosity has a greater impact on the magnitude and extent of seepage force compared to injection rate,and that lower viscosity and injection rate correspond to shorter hydraulic fracture ***,seepage force influences the direction of HF propagation,causing HFs to deflect towards the side of the reservoir with weaker cementation and higher permeability.

关键词： Hydraulic fracturing Seepage force Fracture propagation Discrete element method Reservoir heterogeneity

A survey on federated learning:a perspective from multi-party computation

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Frontiers of Computer Science 2024年第1期18卷 93-103页

作者： Fengxia LIU Zhiming zheng Yexuan SHI Yongxin TONG yi ZHANG Institute of Artificial Intelligence and Key Laboratory of Mathematics Informatics Behavioral Semantics Beihang UniversityBeijing 100191China State Key Laboratory of Software Development Environment and Advanced Innovation Center for Future Blockchain and Privacy Computing Beihang UniversityBeijing 100191China Pengcheng Laboratory Shenzhen 518055China Zhongguancun Laboratory Beijing 100190China Institute for Mathematical Sciences and Engineering Research Center of Financial Computing and Digital Engineering Renmin University of ChinaBeijing 100872China

Federated learning is a promising learning paradigm that allows collaborative training of models across multiple data owners without sharing their raw *** enhance privacy in federated learning,multi-party computation can be leveraged for secure communication and computation during model *** survey provides a comprehensive review on how to integrate mainstream multi-party computation techniques into diverse federated learning setups for guaranteed privacy,as well as the corresponding optimization techniques to improve model accuracy and training *** also pinpoint future directions to deploy federated learning to a wider range of applications.

关键词： sfederated learning multi-party ycomputation privacy-preserving data mining distributed learning

Distributed Economic MPC for Synergetic Regulation of the Voltage of an Island DC Micro-Grid

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IEEE/CAA Journal of Automatica Sinica 2024年第3期11卷 734-745页

作者： yi zheng Yanye Wang Xun Meng Shaoyuan Li Hao Chen IEEE the Department of Automation Shanghai Jiao Tong UniversityShanghai 200240 the Key Laboratory of System Control and Information Processing Ministry of Education of ChinaShanghai 200240China Haixi Institutes Chinese Academy of SciencesJinjiang 362216China

In this paper,distributed model predictive control(DMPC) for island DC micro-grids(MG) with wind/photovoltaic(PV)/battery power is proposed,which coordinates all distributed generations(DG) to stabilize the bus voltage together with the insurance of having computational efficiency under a real-time *** on the feedback of the bus voltage,the deviation of the current is dispatched to each DG according to cost over the prediction ***,to avoid the excessive fluctuation of the battery power,both the discharge-charge switching times and costs are considered in the model predictive control(MPC) optimization problems.A Lyapunov constraint with a time-varying steady-state is designed in each local MPC to guarantee the stabilization of the entire *** voltage stabilization of the MG is achieved by this strategy with the cooperation of *** numeric results of applying the proposed method to a MG of the Shanghai Power Supply Company shows the effectiveness of the distributed economic MPC.

关键词： Distributed model predictive control(DMPC) Lyapunovbased model predictive control micro-grid(MG) voltage control

Organic Brønsted Acid-Catalyzed Stereoselective Cationic RAFT Polymerization:The Effect of RAFT Agents

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Chinese Journal of Polymer Science 2024年第6期42卷 711-717页

作者： zheng-yi Zhang Zan Yang Yun Liao Sai-Hu Liao Key Laboratory of Molecule Synthesis and Function Discovery(Fujian Province University) College of ChemistryFuzhou UniversityFuzhou350108China State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen361005China Beijing National Laboratory for Molecular Sciences Beijing100190China

The tacticity of vinyl polymers is a key factor affecting the properties of ***,organic Brønsted acids have been demonstrated as effective catalysts for the development of highly stereoselective cationic reversible addition-fragmentation chain transfer(RAFT)polymerizations of vinyl ethers,in which the use of RAFT agents could allow the control the molecular weight and tacticity of polymer products ***,the effect of RAFT agents on the tacticity-regulation remains elusive and lacks of *** this study,we synthesized four types of RAFT agents and evaluated their influence in the stereoselective cationic polymerization of isobutyl vinyl ether in the presence of PADI as a Brønsted acid catalyst,which unveils that the Z group of RAFT agents could not only affect the polydispersity of the products,but also exert a profound effect on the *** extensive screening of the RAFT agents,high stereoregularity(isotacticity,90%m)was obtained when using dithiocarbonate ester-type RAFT agents with a benzyloxy Z group.

关键词： Bronsted acid catalysis Stereoselective cationic polymerization RAFT polymerization Chain transfer agents Tacticity

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林下参人参皂苷分析

吉林农业大学学报 2008年第4期30卷 486-491页

作者：郑毅男吉林农业大学中药材学院长春130118

不同的提取方法对皂苷含量影响显著,热回流法与超声波法和微波法相比对人参皂苷的提取率最高,而且在加热过程中丙二酰基人参皂苷分别转化成相应的中性皂苷。对生长在吉林省的栽培参和林下参的6种主要皂苷(Rg1,Re,Rb1,Rc,Rb2,Rd)进行高... 详细信息

不同的提取方法对皂苷含量影响显著,热回流法与超声波法和微波法相比对人参皂苷的提取率最高,而且在加热过程中丙二酰基人参皂苷分别转化成相应的中性皂苷。对生长在吉林省的栽培参和林下参的6种主要皂苷(Rg1,Re,Rb1,Rc,Rb2,Rd)进行高效液相色谱(HPLC)分析,结果显示不同地区栽培的人参主根中皂苷含量存在显著差别,且人参皂苷Rg1和Re的化学型组成比例差异较大。吉林人参明显存在3种化学型,分别为高Rg1低Re化学型,低Rg1高Re化学型,Rg1、Re几乎相等化学型。人参不同种群、不同生长年限、不同栽培方式对人参皂苷含量及组成比例都会产生影响。

关键词：人参林下参人参皂苷化学型

Data driven reduced modeling for fluidized bed with immersed tubes based on PCA and Bi-LSTM neural networksAuthor links open overlay panel

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Particuology 2024年第8期91卷 1-18页

作者： Jiabin Fang Wenkai Cu Huang Liu Huixin Zhang Hanqing Liu Jinjia Wei Xiang Ma nan zheng School of Chemical Engineering and Technology Xi'an Jiaotong UniversityXi'anShaanxi 710049China

The fast and accurate reduced-order modeling of fluidized beds is a challenging task in the field of fluid dynamics,owing to their high dimensionality and nonlinear dynamic *** this study,a nonintrusive reduced order modeling method,the reduced order model based on principal component analysis and bidirectional long short-term memory networks(PBLSTM ROM),was developed to capture complex spatio-temporal dynamics of fluidized *** combining principal component analysis and Bidirectional long-short-term memory networks,the PBLSTM ROM effectively extracted dynamic evolution information without any prior knowledge of governing equations,enabling reduced-order modeling of unsteady flow *** PBLSTM ROM was validated using the solid volume fraction and gas velocity flow fields of a fluidized bed with immersed tubes,showing superior performance over both the PLSTM and PANN ROMs in accurately capturing temporal changes in the fluidization fields,especially in the region near immersed tubes where severe fluctuations ***,the PBLSTM ROM improved the simulation speed by five orders of magnitude compared to traditional computational fluid dynamics *** findings suggest that the PBLSTM ROM presents a promising approach for analyzing the complex fluid flows in engineering practice.

关键词： Reduced order modeling Fluidized bed Deep learning Bi-LSTM