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Progress of hidden spin polarization in inversion-symmetric crystals

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Science China(Physics,Mechanics & Astronomy) 2022年第3期65卷 1-18页

作者： shan Guan Jia-Xin Xiong Zhi Wang Jun-Wei luo State Key Laboratory of Superlattices and Microstructures Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Beijing Academy of Quantum Information Sciences Beijing 100193China

Hidden spin polarization refers to that doubly degenerate bands protected by combined inversion and time-reversal symmetry in nonmagnetic inversion-symmetric crystals could have opposite non-zero local spin polarizations, which are spatially separated in two real-space sectors paired by the inversion symmetry. Since its first prediction from ab initio calculation, hidden spin polarization has inspired tremendous interest and has been observed experimentally due to its intriguing fundamental properties as well as the great potential for applications. Moving forward, the search for moment-dependent spin splitting has also been extended to antiferromagnets even without considering spin-orbit coupling. This paper systematically reviews recent works in this field with a focus on basic concepts and material realization. It also details several remaining bottlenecks and suggests possible avenues for future research.

关键词： spin-orbit coupling hidden spin polarization tight-binding model ab initio calculation

New observation on a class of old reactions:Chemoselectivity for the solvent-free reaction of aromatic aldehydes with alkylketones catalyzed by a double-component inorganic base system

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Science China Chemistry 2010年第5期53卷 1094-1100页

作者： shan, ZiXing luo, XinXiang Hu, Lin Hu, XiaoYun Department of Chemistry Wuhan University Wuhan 430072 China Department of Chemistry and Environment Engineering Hunan City University Yiyang 413049 China

Solvent-free reactions of aromatic aldehydes with three representative ketones,including acetophenone,acetone and cyclohexanone,have been examined under the catalysis of a low-cost inorganic base system consisting of NaOH and *** was found that the chemoselectivity of the reactions is in close relationship with the composition of the reactants and the doublecomponent *** the optimized experimental conditions,1,2,3,4,5-pentasubstituted cyclohexanols,α,β-unsaturated ketones and Claisen-Schmidt bicondensation products were obtained in high *** Kostanecki's triketones were separated,The composition and structure were affirmed by X-ray crystallographic analysis.

关键词： solvent-free reaction solid base mixture catalysis chemoselectivity aldehyde-ketone reaction

Fast counting the cardinality of flows for big traffic over sliding windows

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Frontiers of Computer Science 2017年第1期11卷 119-129页

作者： Jingsong shan Yinjin FU Guiqiang NI Jianxin luo Zhaofeng WU College of Command Information Systems PLA University of Science and Technology Nanjing 223002 China Huaiyin Institute of Technology Huaian 221002 China

Counting the cardinality of flows for massive high-speed traffic over sliding windows is still a challenging work under time and space constrains, but plays a key role in many network applications, such as traffic management and routing optimization in software defined network. In this pa- per, we propose a novel data structure （called LRU-Sketch） to address the problem. The significant contributions are as follows. 1） The proposed data structure adapts a well-known probabilistic sketch to sliding window model; 2） By using the least-recently used （LRU） replacement policy, we design a highly time-efficient algorithm for timely forgetting stale information, which takes constant （O（1）） time per time slot; 3） Moreover, a further memory-reducing schema is given at a cost of very little loss of accuracy; 4） Comprehensive ex- periments, performed on two real IP trace files, confirm that the proposed schema attains high accuracy and high time *** including IEEE TPDS, ACM ToS, JCST, MIDDLEWARE, CLUSTER, NAS, etc. Currently, his research interests include big data management, cloud storage, and distributed file systems.

关键词： probabilistic data structure sketch streaming data cardinality flow

DETECTION METHOD OF SPOT WELDING BASED ON MULTI-INFORMATION FUSION AND FRACTAL

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维普期刊数据库

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Chinese Journal of Mechanical Engineering 2008年第6期21卷 76-81页

作者： LIU Pengfei shan Ping luo Zhen SHEN Junqi QIN Hede luoyang Ship Material Research Institute Luoyang 471039 China School of Material Science and Engineering Tianjin University Tianjin 300072 China School of Xinxiang Etectromechanical Engineering Xinxiang 453000 China

A novel detection method of support vector machine （SVM） based on fractal dimension of signals is presented. And models of SVM are made based on nugget size defects of spot welding. Classification using these trained SVM models is done to signals of spot welding. It is shown from effect of different SVM models that these models with different inputs. In detection of defects, these models with inputs including sound signal have a high percentage of accuracy, the detection accuracy of these models with inputs including voltage signal will reduce. So the SVM models based on fractal dimensions of sound are some optimal nondestructive detection ones. At last a comparison between SVM detection model and ANNS detection model is researched which indicates that SVM is a more effective measure than Artificial neural networks in detection of nugget size defects during spot welding.

关键词： Multi-information fusion Support vector machine Box counting dimension Detection Spot welding

Improved electrochemical performances of yttrium oxyfluoride-coated Li[Li0.2Mn0.54Ni0.13Co0.13]O2 for lithium ion batteries

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Journal of Energy Chemistry 2018年第4期27卷 1239-1246页

作者： Yaxin Hao Fangning Yang Didi luo Jianhua Tian Zhongqiang shan School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350.China The 18th Research Institute of China Electronics Technology Group Corporation Tianjin 300384.China

The Li-rich layered oxides show a higher discharge capacity over 250 mAh/g and have been developed into a promising positive material for lithium ion batteries. A rare earth metal oxyfluoride YOF-coated Li[Lio.2Mno.54Ni0.13Co0.13]O2 composites have been synthesized by a simple wet chem- ical method. Crystal structure, micro-morphology and element valence of the pristine and YOF-coated Li[Li0.2Mn0.54Ni0.13Co0.13]O2 materials are characterized by XRD, SEM, TEM, and XPS. The results indicate that all materials exhibit a typical layered structure, and are made up of small and homogenous parti- cles ranging from 100 nm to 200 nm. In addition, YOF layer with a thickness of approximately 3-8 nm is precisely coated on the surface of the Li[Li0.2Mn0.54Ni0.13Co0.13]02. Constant current charge/discharge tests at various current densities show that the electrochemical performance of 2 wt% YOF-coated Li[Li0.2Mn0.54Ni0.13Co0.13]O2 has been improved significantly. 2 wt% YOF-coated Li[Li0.2Mn0.54Ni0.13Co0.13]O2 delivers the highest discharge capacity of 250.4 mAh/g at 20 mA/g among all the samples, and capacity retention of 87% after 100 charge/discharge cycles at 200 mA/g while that of the pristine one is only 81.6%. The superior electrochemical performance of 2wt% YOF-coated sample is ascribed to YOF coating layer, which could not only reduce side reactions between the electrode and liquid electrolyte, but also promote lithium ion migration.

关键词： Li[Li0.2 Mn0.54 Ni0.13 Co0.13]O2 YOF-coated Cathode material Lithium ion battery

Study on semantic-oriented hybrid indexing strategy of resource metadata in peer-to-peer network

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第1期8卷 88-94页

作者： LIU Zhen ZHOU Mao-wei HUANG Hong-bin luo Xue-shan College of Information System and Management National University of Defense Technology Changsha 410073 China

Applying ontology to describe resource metadata richly in the peer-to-peer environment has become current research trend. In this semantic peer-to-peer environment, indexing semantic element of resource description to support efficient resource location is a difficult and challenging problem. This paper provided a hybrid indexing architecture, which combines local indexing and global indexing. It uses community strategy and semantic routing strategy to organize key layer metadata element and uses DHT (distributed hash table) to index extensional layer metadata element. Compared with related system, this approach is more efficient in resource location and more scalable.

关键词： Peer-to-peer (P2P) Ontology Metadata Resource indexing

Functional connectivity changes during migraine treatment with electroacupuncture at Shuaigu(GB8)

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Journal of Integrative Medicine 2022年第3期20卷 237-243页

作者： Xiang-yu Wei Shi-lei luo Hui Chen shan-shan Liu Zhi-gang Gong Song-hua Zhan Department of Radiology Shuguang HospitalShanghai University of Traditional Chinese MedicineShanghai 201203China Department of Acupuncture&Moxibustion Shuguang HospitalShanghai University of Traditional Chinese MedicineShanghai 201203China

Objective:To investigate the changes in the functional connectivity(FC)in the right insula between migraine without aura(MWoA)and healthy controls by using resting-state functional magnetic resonance imaging(rs-fMRI),and to observe the instant alteration of FC in MWoA during electroacupuncture(EA)stimulation at Shuaigu(GB8).Methods:A total of 30 patients with MWoA(PM group)and 30 healthy controls(HC group)underwent rs-fMRI *** PM group underwent a second rs-fMRI scan while receiving EA at *** right insula subregions,including the ventral anterior insula(vAI),dorsal anterior insula(dAI)and posterior insula(PI),were selected as the seed points for FC ***:Aberrant FC,including dAI with right postcentral gyrus,PI with left precuneus,was found among PM before EA(PMa),PM during EA(PMb)and ***,decreased FC between dAI and the right postcentral gyrus was found in the PMa compared to the HC and *** FC between the PI and left precuneus was found in the PMa compared to the HC and *** analysis showed that the FC value of the right postcentral gyrus in PMa was negatively correlated with the scores of Hamilton Rating Scale for Depression and Hamilton Rating Scale for *** FC value of the left precuneus in PMa was positively correlated with the visual analogue scale ***:The alteration of FC between the right insula subregions and multiple brain regions may be an important index for *** at GB8 was able to adjust the FC between the right insula subregions and parietal lobe,namely,the right dAI and right postcentral gyrus,and the right PI and left precuneus,thereby rendering an instant effect in the management of MWoA.

关键词： Functional status Migraine Electroacupuncture Shuaigu(GB8) Functional magnetic resonance imaging

Photocatalytic vinyl radical-mediated multicomponent 1,4-/1,8-carboimination across alkynes and olefins/(hetero)arenes

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Science China Chemistry 2024年第2期67卷 558-567页

作者： shan-shan Li Yu-Shi Jiang Xue-Ling luo Xuming Ran Yuqiang Li Dong Wu Cheng-Xue Pan Peng-Ju Xia School of Chemistry and Pharmaceutical Sciences Guangxi Normal UniversityGuilin541004China shanghai Artificial Intelligence Laboratory Shanghai200433China The Institute for Advanced Studies Wuhan UniversityWuhan430064China

We developed a highly selective and efficient multicomponent transformation by utilizing alkynes and olefins/(hetero)arenes through photoinduced energy-transfer *** reaction involves the formation of three distinct chemical bonds,namely C(sp~3)–C(sp~2),C(sp~2)–C(sp~3),and C(sp~3)–N,in a single coordinated *** strategy used a vinyl radical-mediated radical relay approach under mild conditions,exhibiting a broad substrate scope(>70 examples),excellent functional-group tolerance,and remarkable regio-and *** the utilization of a combination of experimental techniques and density functional theory(DFT),we delved deeper into the mechanistic intricacies of this distinctive *** revealed that the selective radical addition to electron-deficient alkynes,rather than olefins,was governed by the inherent reactivity of alkyl *** discovery presented a highly effective approach for the synthesis of stereodefined multisubstituted alkenes.

关键词： alkyne-olefin coupling DFT studies regio-and anti-stereoselectivity multisubstituted alkenes

LOOKNoC: a low-loss, non-blocking, scalable passive optical interconnect network-on-chip architecture

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The Journal of China Universities of Posts and Telecommunications 2021年第1期28卷 94-106页

作者： Deng Junyong Wu Haoyue luo Jiaying shan Rui Liu Xinchuang School of Eltronie and Information Enginering Xian Universily of Posts and TelecommunicaionsXian 710121China

Low-loss, non-blocking, scalable passive optical interconnect network on-chip(LOOKNoC) structure was proposed based on 2×2 optical exchange switches, using wavelength division multiplexing(WDM)technology to expand to 8×8, 16×16, 32×32, 64×64 passive optical interconnection networks, which can achieve non-blocking communication. The experimental results show that based on the 16×16 optical interconnection network structure, the number of microring resonators(MRs) in LOOKNoC was reduced by 90.9%, 90.9%, 20.0% and 75.0% compared with the generic wavelength-routed optical router(GWOR), λ-router, topology and CrossBar structure. By testing the performance parameters based on the structure of 16×16 by the OMNET++ platform, as the result shows, the average insertion loss of LOOKNoC is 3.0%, 11.6%, 4.8% and 16.7% less than that of GWOR, λ-router, Mesh, and CrossBar structures.

关键词： network-on-chip passive optical interconnect wavelength division multiplexing low-loss non-blocking scalable