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On-chip stackable dielectric laser accelerator

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Nuclear Science and Techniques 2023年第2期34卷 79-87页

作者： Bin Sun Yang‑Fan He ruo‑Yun Luo Tai‑Yang Zhang Qiang Zhou Shao‑Yi wang Jian Zheng Zong‑qing Zhao CAS Key Laboratory of Geospace Environment Department of Plasma Physics and Fusion EngineeringUniversity of Science and Technology of ChinaHefei 230026China Laser Fusion Research Center CAEPP.O.Box 919986Mianyang 621900China The Sciences and Technology on Plasma Physics Laboratory CAEPMianyang 621900China Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 610054China Department of Nuclear Plasmaand Radiological EngineeringUniversity of Illinois at Urbana-Champaign104 South Wright StreetUrbanaIL 61801USA CAS Key Laboratory of Quantum Information University of Science and Technology of ChinaHefei 230026China IFSA Collaborative Innovation Center Shanghai Jiao Tong UniversityShanghai 200240China CAS Center for Excellence in Ultra-Intense Laser Science Shanghai 201800China

In this paper,we propose a novel stacked laser dielectric acceleration *** structure is based on the inverse Cherenkov effect and represented by a parametric design *** to existing dielectric laser accelerators relying on the inverse Smith–Purcell effect,the proposed structure provides an extended-duration synchronous acceleration field without requiring the pulse front tilting *** advantage significantly reduces the required pulse *** addition,the easy to integrate layered structure facilitates cascade acceleration,and simulations have shown that low-energy electron beams can be cascaded through high gradients over extended *** practical advantages demonstrate the potential of this new structure for future chip accelerators.

关键词： Dielectric laser accelerator Inverse Cherenkov effect Laser-driven particle acceleration

Chrysotus Meigen(Diptera: Dolichopodidae) from Shanxi, China, with descriptions of two new species

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Zoological Systematics 2015年第1期40卷 86-92页

作者： ruo-Si Liu Meng-qing wang Ding Yang Department of Entomology China Agricultural University Beijing Entry-Exit Inspection and Quarantine Bureau Technology Center Institute of Plant Protection Chinese Academy of Agricultural Sciences

The species of the genus Chrysotus Meigen from Shanxi, China are reviewed, Two species are described as new to science： C. shanxiensis sp. nov. and C. thornpenis sp. nov. C. biprojicienus Wei ＆ Zhang and C. serratus wang ＆ Yang are recorded from Shanxi for the first time. A key to the species of Chrysotus from Shanxi is presented.

关键词： Diptera Dolichopodidae Diaphorinae Chrysotus Shanxi new species.

Two folate-derived analogues from an aqueous decoction of Uncaria rhynchophylla

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Chinese Journal of Natural Medicines 2019年第12期17卷 928-934页

作者： wang Yue GUO qing-Lan LI ruo-Fei XU Cheng-Bo ZHU Cheng-Gen SHI Jian-Gong State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia Medica Chinese Academy of Medical Sciences and Peking Union Medical College

Two new folate-derived analogues,named uncarophyllofolic acids A(1)and B(2),respectively,were isolated from the Uncaria rhynchophylla hook bearing stem(Gouteng in Chinese).The distinct stereochemical structures of 1 and 2 were determined by spectroscopic data analysis in combination with acidic hydrolysis and Marfey’s derivatization,along with comparison of their specific rotation and Cotton effect(CE)data with those of the biogenetically related known derivatives as well as theoretical calculations of electronic circular dichroism(ECD)spectra.A plausible biosynthetic pathway of 1 and 2,associating to folate metabolism and the previously reported orychophragines A-C from Orychophragmus violaceus,is discussed.

关键词： Rubiaceae Uncaria rhynchophylla Folate derivative Uncarophyllofolic acid Folate metabolism

Distribution of platinum group elements in road dust in the Beijing metropolitan area, China

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Journal of Environmental Sciences 2007年第1期19卷 29-34页

作者： wang Juan ZHU ruo-hua SHI Yan-zhi Department of Chemistry Capital Normal University Beijing 100037 China

Dust samples collected from the Beijing metropolitan area （China） were evaluated to determine the distribution and the concentration of platinum group elements （PGEs）. The dust particles that were smaller than 100 mesh size fraction （150 μm） were analyzed after aqua regia digestion. Concentrations ofPt, Rh, and Pd were found to be between 3.96 and 356.3 ng/g, 2.76 and 97.11 ng/g, and 0.1 and 124.9 ng/g, respectively, in the urban areas of Beijing, whereas for the background samples collected from the suburbs of Beijing, the concentrations of Pt, Pd, and Rh were very low and ranged from 0.1 to 0.9 ng/g, 0.5 to 1.4 ng/g, and 0.8 to 2.2 rig/g, respectively. The distributions of PGEs in road dust were an accurate reflection of the levels of pollution and were found to match with the local traffic conditions. A strong positive correlation was established among all the dements found in road dust. This suggests that emissions of abraded fragments from vehicle exhausts may be the source of the high concentration of Pt, Rh, and Pd in road dust along the main roads of Beijing.

关键词： platinum (Pt) palladium (Pd) rhodium (Rh) road dust distribution environmental pollution

Method of data cleaning for network traffic classification

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The Journal of China Universities of Posts and Telecommunications 2014年第3期21卷 35-45页

作者： wang ruo-yu LIU Zhen ZHANG Ling School of Computer Science and Engineering South China University of Technology

Network traffic classification aims at identifying the application types of network packets. It is important for Internet service providers （ISPs） to manage bandwidth resources and ensure the quality of service for different network applications However, most classification techniques using machine learning only focus on high flow accuracy and ignore byte accuracy. The classifier would obtain low classification performance for elephant flows as the imbalance between elephant flows and mice flows on Internet. The elephant flows, however, consume much more bandwidth than mice flows. When the classifier is deployed for traffic policing, the network management system cannot penalize elephant flows and avoid network congestion effectively. This article explores the factors related to low byte accuracy, and secondly, it presents a new traffic classification method to improve byte accuracy at the aid of data cleaning. Experiments are carried out on three groups of real-world traffic datasets, and the method is compared with existing work on the performance of improving byte accuracy. Experiment shows that byte accuracy increased by about 22.31% on average. The method outperforms the existing one in most cases.

关键词： network traffic classification byte accuracy elephant flow mice flow machine learning

Fructus Zanthoxyli extract improves glycolipid metabolism disorder of type 2 diabetes mellitus via activation of AMPK/PI3K/Akt pathway:Network pharmacology and experimental validation

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Journal of Integrative Medicine 2022年第6期20卷 543-560页

作者： Ting Zhang qing Zhang Wei Zheng Ting Tao ruo-lan Li Li-yu wang Wei Peng Chun-jie Wu School of Pharmacy Chengdu University of Traditional Chinese MedicineChengdu 611137Sichuan ProvinceChina

Objective:This study investigated the potential mechanisms behind the beneficial effects of Fructus Zanthoxyli(FZ)against type 2 diabetes mellitus(T2DM)based on network pharmacology and experimental ***:Ultra-high-performance liquid chromatography coupled with hybrid quadrupole-orbitrap high-resolution mass spectrometry,and gas chromatography-mass spectrometry were used to identify the constituents of ***,the differentially expressed genes linked to the treatment of diabetes with FZ were screened using online databases(including Gene Expression Omnibus database and Swiss Target Prediction online database),and the overlapping genes and their enrichment were analyzed by Kyoto Encyclopedia of Genes and Genomes(KEGG).Finally,the pathway was verified by in vitro experiments,and cell staining with oil red and Nile red showed that the extract of FZ had a therapeutic effect on ***:A total of 43 components were identified from FZ,and 39 differentially expressed overlapping genes were screened as the possible targets of FZ in *** dug component-target network indicated that PPARA,PPARG,PIK3R3,JAK2 and GPR88 might be the core genes targeted by FZ in the treatment of ***,the enrichment analysis of KEGG showed that effects of FZ against T2DM were closely correlated with the adenosine monophosphate-activated protein kinase(AMPK)and phosphatidylinositol-3-kinase(PI3K)/protein kinase B(Akt)signaling *** vitro experiments further confirmed that FZ significantly inhibited palmitic acid-induced lipid formation in Hep G2 ***,FZ treatment was able to promote the AMPK and PI3K/Akt expressions in Hep G2 ***:Network pharmacology combined with experimental validation revealed that FZ extract can improve the glycolipid metabolism disorder of T2DM via activation of the AMPK/PI3K/Akt pathway.

关键词： Fructus Zanthoxyli Zanthoxylum bungeanum Maxim Type 2 diabetes mellitus Network pharmacology Glucose and lipid metabolism Phosphatidylinositol-3-kinase AMPK/PI3K/Akt

Effect of Electric Field on the Electron-Surface Optical Phonon Scattering Rates in Quantum Wires

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Chinese Physics Letters 1996年第4期13卷 297-300页

作者： CHANG Kai wang ruo-zhen MA Ben-kun Department of Physics Beijing Normal UniversityBeijing 100875

By using the variational method and the dielectric continuum model,we investigate the effect of electric Held on the intrasubband scattering rates of electron-surface optical *** results show that the scattering rates tend to increase with the electric field *** scattering rates become significant for wide quantum well wire and sufficiently high fields.

关键词： strength. Electron variational

Optimal state feedback control of brushless direct-current motor drive systems based on Lyapunov stability criterion

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第12期8卷 1889-1893页

作者： wang Wei JIN ruo-jun JIANG Jing-ping College of Mechatronics Engineering China .Jiliang University Hangzhou 310018. China School of Electrical Engineering Zhejiang University Hangzhou 310027 China

This paper develops a unified methodology for a real-time speed control of brushless direct-current motor drive systems in the presence of measurement noise and load torque disturbance. First, the mathematical model and hardware structure of system is established. Next, an optimal state feed back controller using the Kalman filter state estimation technique is derived. This is followed by an adaptive control algorithm to compensate for the effects of noise and disturbance. Those two algorithms working together can provide a very-high-speed regulation and dynamic response over a wide range of operating conditions. Simulated responses are presented to highlight the effectiveness of the proposed control strategy.

关键词： Brushless DC motor Adaptive control Optimal state feedback

Thermodynamics and kinetics of alumina extraction from fly ash using an ammonium hydrogen sulfate roasting method

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International Journal of Minerals,Metallurgy and Materials 2014年第2期21卷 144-149页

作者： ruo-chao wang Yu-chun Zhai Zhi-qiang Ning School of Materials and Metallurgy Northeastern University

A novel method was developed for extracting alumina （Al2O3） from fly ash using an ammonium hydrogen sulfate （NH4HSO4） roasting process, and the thermodynamics and kinetics of this method were investigated. The thermodynamic results were verified experi-mentally. Thermodynamic calculations show that mullite present in the fly ash can react with NH4HSO4 in the 298-723 K range. Process op-timization reveals that the extraction rate can reach up to 90.95% when the fly ash reacts with NH4HSO4 at a 1：8 mole ratio of Al2O3/NH4HSO4 at 673 K for 60 min. Kinetic analysis indicates that the NH4HSO4 roasting process follows the shrinking unreacted core model, and inner diffusion through the product layer is the rate-controlling step. The activation energy is calculated to be 16.627 kJ/mol;and the kinetic equation can be expressed as 1-（2/3）α-（1-α）2/3=0.0374t exp[-16627/（RT）], whereαis the extraction rate and t is the roasting temperature.

关键词： ammonium hydrogen sulfate ore roasting fly ash alumina thermodynamics kinetics