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X-Ray Fine Structure of a Limb Solar Flare Revealed by Insight-HXMT,RHESSI and Fermi

Research in Astronomy and Astrophysics 2022年第5期22卷 47-55页

作者： ping Zhang Wei wang Yang Su Shuangnan Zhang Liming Song Fangjun Lu Shu Zhang Department of Physics and Technology Wuhan UniversityWuhan 430072China WHU-NAOC Joint Center for Astronomy Wuhan UniversityWuhan 430072China Purple Mountain Observatory of the Chinese Academy of Sciences Nanjing 210023China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China

We conduct a detailed analysis of an M1.3 limb flare occurring on 2017 July 3,which have the X-ray observations recorded by multiple hard X-ray telescopes,including Hard X-ray Modulation Telescope(Insight-HXMT),Ramaty High Energy Solar Spectroscopic Imager(RHESSI),and the Fermi Gamma-ray Space Telescope(Fermi).Joint analysis has also used the extreme ultraviolet(EUV)imaging data from the Atmospheric Imaging Assembly(AIA)aboard the Solar Dynamic *** hard X-ray spectral and imaging evolution suggest a lower corona source,and the non-thermal broken power law distribution has a rather low break energy~15 *** EUV imaging shows a rather stable plasma configuration before the hard X-ray peak phase,and accompanied by a filament eruption during the hard X-ray flare peak *** X-ray image reconstruction from RHESSI data only shows one foot point *** also determined the DEM for the peak phase by SDO/AIA *** integrated EM beyond 10 MK at foot point onset after the peak phase,while the>10 MK source around reconnection site began to *** evolution of EM and hard X-ray source supports lower corona plasma heating after non-thermal energy *** combination of hard X-ray spectra and images during the limb flare provides the understanding on the interchange of non-thermal and thermal energies,and relation between lower corona heating and the upper corona instability.

关键词： Sun flares-Sun corona-Sun X-rays-gamma-rays-plasmas-radiation mechanisms non-thermal-radiation mechanisms thermal

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Evolution regularity of the Neogene shallow water delta in the Laibei area, Bohai Bay Basin, northern China

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Journal of Palaeogeography 2014年第3期3卷 257-269页

作者： Jian-ping Li Hao Liu cheng-Min Niu Rui-Bo Guo Exploration & Exploitation Research Institute Tianjin Branch of China National Offshore Oil Corporation School of Ocean Sciences China University of Geosciences (Beijing) Petroleum Engineering College China University of Petroleum (East China)

According to the characteristics of sedimentary microfacies, unique vertical depositional sequences and well logging response, the authors propose that a shallow water delta was widely developed in the Neogene of the Laibei area, Bohai Bay Basin of northern China. Based on seismic minimum amplitude slices, well logging data, test analytical data and so forth, detailed research on the evolution of the shallow water delta of the Neogene Lower Member of Minghuazhen Formation was conducted. The results indicate that the third-order sequence base level controls sandbody types. During a period of low base level, a distribu- tary channel sandbody of shallow water deltaic plain was developed. With base level rising, the sandbody type gradually changed into a subaqueous distributary channel sandbody and a sheet sand can be found as well. The fourth-order sequence base level controls mediumshort term evolution of the sandbody. Within a sequence, due to the rising and falling of base level, the sandbody assemblages are identified as an upward-coarsening type, an upwardfining and a compound type respectively. Regionally, from the Laibei Low Uplift to the Huang- hekou Sag, the shallow water delta evoluted from a dendritic shape, to a cuspate shape and finally to a sheet shape.

关键词： shallow water delta evolution Lower Member of the Minghuazhen Formation Neogene Laibei area Huanghekou Sag Bohai Bay Basin

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Finite-time Reliable Stabilization for Switched Stochastic Systems Under Asynchronous Switching

Finite-time Reliable Stabilization for Switched Stochastic S...

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第25届中国控制与决策会议

作者： wang Ronghao Qian Zhigen Xing Jianchun wang ping Yang Qiliang College of Defense Engineering PLA University of Science and Technology PLA Academy of National Defense Information

ISBN: (纸本)9781467355339

In this paper, the finite-time stabilization problems for switched stochastic systems are addressed. Firstly, when there exists asynchronous switching between the controller and the system, a sufficient condition for the existence of stabilizing switching law for switched stochastic systems is derived. It is proved that the switched stochastic systems are finite-time stabilizable under asynchronous switching satisfying the average dwell-time condition. Furthermore, the problem of reliable control for switched stochastic systems under asynchronous switching is also investigated. Finally, a numerical example is given to illustrate the effectiveness of the proposed method.

关键词： Asynchronous Switching Switched Stochastic Systems Average Dwell-time Finite-time Reliable Control

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Effect of Post-Annealing on Structural and Electrical Properties of ZnO:In Films

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Chinese Physics Letters 2019年第4期36卷 79-82页

作者： Guo-ping Qin Hong Zhang Hai-Bo Ruan Jiang wang Dong wang Chun-Yang Kong College of Physics and Electronic Engineering Chongqing Normal University College of Physics Chongqing University Research Center for Materials Interdisciplinary Sciences Chongqing University of Arts and Sciences

Indium-doped ZnO(ZnO:In) films are deposited on quartz substrates by rf magnetron sputtering. The effects of post-annealing on structural, electrical, optical and Raman properties are investigated by x-ray diffraction,Raman scattering, Hall measurement and first-principles calculation. The results indicate that all of the ZnO:In films have excellent crystallinity with a preferred ZnO(002) orientation. It is found that the incorporation of In can dramatically increase the intensity of the 274 cm^(-1) Raman mode. However, both post-annealing treatment and increasing O_2 partial pressure in the process of preparing thin films can reduce the intensity of the 274 cm^(-1) mode or even eliminate it, and relax compressive stress of the ZnO:In film judged by analyzing the shifts of the(002) Bragg peaks and E_2(high) mode. Finally, the origin of the 274 cm^(-1) mode is inferred to be the vibration of Zn interstitial(Zni) defects, which play a crucial role in the high electron concentration and low resistivity of ZnO:In films annealed in an appropriate temperature range(450–600℃).

关键词： structural Hall measurement temperature

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Origin and the Hardening Mechanism of Twinned Lenticular Martensite in a Fe-33Ni Alloy

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Acta Metallurgica Sinica(English Letters) 2023年第6期36卷 899-905页

作者： Yong Li Zuohua wang Lihua Qian Jian Zhao Wu Zhang ping Wei Hongwang Zhang National Engineering Research Center for Equipment and Technology of Cold Strip Rolling College of Mechanical EngineeringYanshan UniversityQinhuangdao 066004China State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China School of Physics Huazhong University of Science and TechnologyWuhan 430074China China Copper Huazhong Copper Cooperation Limited Huangshi 435004China College of Weaponry Engineering Naval University of EngineeringWuhan 430033China

The twinned substructure of lenticular martensite in a quenched Fe–33Ni alloy was *** contrary to the traditional viewpoint that the twinned laths come from{112}deformation twins and show insignificant hardening,we demonstrate that they are actually originated from the twinned Kurdjumov Sachs(KS)variants and can give rise to 3–4 times hardening up to~420 HV(~130 HV for the starting sample).The underlying mechanisms responsible for the propensity for twinned variants and the carbon-independent hardening for Fe–Ni system were discussed.

关键词： Twinned variants Midrib Lenticular martensite Hardening mechanism Fe-33Ni

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Artificial intelligence for brain disease diagnosis using electroencephalogram signals

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第10期25卷 914-940页

作者： Shunuo SHANG Yingqian SHI Yajie ZHANG Mengxue LIU Hong ZHANG ping wang Liujing ZHUANG Biosensor National Special Laboratory Key Laboratory for Biomedical Engineering of Education MinistryDepartment of Biomedical EngineeringZhejiang UniversityHangzhou 310027China The MOE Frontier Science Center for Brain Science&Brain-Machine Integration Zhejiang UniversityHangzhou 310027China The State Key Lab of Brain-Machine Intelligence Zhejiang UniversityHangzhou 310027China

Brain signals refer to electrical signals or metabolic changes that occur as a consequence of brain cell *** the various non-invasive measurement methods,electroencephalogram(EEG)stands out as a widely employed technique,providing valuable insights into brain *** deviations observed in EEG reading serve as indicators of abnormal brain activity,which is associated with neurological ***‒computer interface(BCI)systems enable the direct extraction and transmission of information from the human brain,facilitating interaction with external ***,the emergence of artificial intelligence(AI)has had a profound impact on the enhancement of precision and accuracy in BCI technology,thereby broadening the scope of research in this *** techniques,encompassing machine learning(ML)and deep learning(DL)models,have demonstrated remarkable success in classifying and predicting various brain *** comprehensive review investigates the application of AI in EEG-based brain disease diagnosis,highlighting advancements in AI algorithms.

关键词： Brain disease Electroencephalography Brain computer interface Artificial intelligence

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Predicting Ecological Distribution of the Toxic Dinoflagellate Alexandrium minutum in China Sea Using Ecological Niche Modeling

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Journal of Ocean University of China 2023年第4期22卷 1119-1128页

作者： wang Changyou ZHENG ping GU Haifeng LUO Zhaohe LUO Zhuhua MAO Longjiang ZHANG Yuanzhi School of Marine Sciences Nanjing University of Information Science and TechnologyNanjing 210044China Third Institute of Oceanography Ministry of Natural ResourcesXiamen 361005China Key Laboratory of Marine Biogenetic Resources Third Institute of OceanographyMinistry of Natural ResourcesXiamen 361005China

Alexandrium minutum from the China Sea produces a range of toxins and causes damage to the local ecosystems and *** is essential to understand environmental factors affecting potential *** distributions of *** in the China Sea were predicted based on maximum entropy modeling,and dominant environmental variables were studied through analyses of variable contributions and response *** results showed that highly suitable areas were mainly located in the southwest of the Yellow Sea,the Laizhou Bay,and north of Haizhou *** coast of the South China Sea was predicted as a low-suitability area,and the coast of the East China Sea as an unsuitable *** temperature of the coldest month(T_min)had the largest drop in permutation importance but a low percent *** probability of presence of *** increased with increasing concentration of nitrate(NO3−)and annual mean temperature(T_ann)over a wide range of *** response curves decreased with increasing concentration of phosphate(PO43−)and ratio of NO_(3)^(−)to PO_(4)^(3−)(N_P_ratio)when PO_(4)^(3)−is above 0.049μmolL^(-1) and N_P_ratio above 4,indicating that low values of PO_(4)^(3−) concentration and N_P_ratio favour the occurrence of *** a predictor,the variance of annual temperature(T_Var)had the highest percent contribution and ***_(4)^(3−) was predicted to have much more information than the other variables,and exhibited the second largest drop in permutation importance and percent *** T_Var and PO_(4)^(3−) are the most important dominant predictor variables.

关键词： Alexandrium minutum MaxEnt,habitat suitability environmental variable potential distributions

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Late Holocene glacier variations indicated by theδ18O of ice core enclosed gaseous oxygen in the central Tibetan Plateau

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Journal of Mountain Science 2023年第2期20卷 325-337页

作者： LI Jiu-le XU Bai-qing wang Ning-lian YAO ping XU Xiang-ke Institute of Tibetan Plateau Research Chinese Academy of SciencesBeijing 100101China State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China CAS Center for Excellence in Tibetan Plateau Earth Sciences Chinese Academy of SciencesBeijing 100101China College of Urban and Environmental Sciences Northwest UniversityXi’an710069China

Theδ18O of ice core enclosed gaseous oxygen(δ18Obub)has been widely used for climate reconstruction in polar ***,less is known about its climatic implication in the mountainous glaciers as the lack of continuous ***,we present a long-term,continuousδ18Obub record from the Tanggula glacier in the central Tibetan Plateau(TP).Based on comparisons of its variation with regional climate and glacier changes,we found that there was a good correlation between the variation of theδ18Obub in this alpine ice core and the accumulation and melting of this *** more developed the firn layer on glacier surface,the more positive theδ***,the more intense the glacier melting,the more negative theδ*** with the chronology of ice core enclosed gases,the glacier variations since the late Holocene in the central TP were *** result showed that there were four accumulation and three deficit periods of glaciers in this *** strongest glacier accumulation period was 1610-300 B.C.,which corresponds to the *** most significant melting period was the last 100 years,which corresponds to the recent global *** Medieval Warm Period was relatively significant in the central ***,during the Little Ice Age,there was no significant glacier accumulation in the central TP,and even short deficit events *** of the late Holocene glacier variation in the central TP with glacier and climate variations in the TP and the Northern Hemisphere showed that it was closely related to the North Atlantic Oscillation.

关键词： Ice core air bubble Stable isotope ratio Gaseous oxygen Glacier variation Late Holocene Tibetan Plateau

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Gastrolatathioneine,an unusual ergothioneine derivative from an aqueous extract of "tian ma":A natural product co-produced by plant and symbiotic fungus

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Chinese Chemical Letters 2016年第10期27卷 1577-1581页

作者： Qing-Lan Guo Sheng Lin Ya-Nan wang cheng-Gen Zhu cheng-Bo Xu Jian-Gong Shi State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical College

Gastrolatathioneine （1）, an unusual natural product derived from ergothioneine, a fungal amino acid containing an imidazole-2-thione moiety, was isolated from an aqueous extract of ＂tian ma＂（the Gastrodia elata rhizomes）. The structure of 1 including the absolute configuration was determined by extensive spectroscopic data analysis, combined with comparison of an experimental circular dichroism spectrum and calculated electronic circular dichroism spectra of stereoisomers, and confirmed by X-ray crystallography. The natural origin of 1 was proved by HPLC-ESIMS analysis of the crude extract. A biogenetic pathway of I is proposed on the basis of metabolic post-modification of ergothioneine that is biosynthesized by a symbiotic fungus. The plant and symbiotic fungus are co-uroducers of 1.

关键词： Gastrodia elataOrchidaceaeErgothioneine(+)-L-N N-bis(4-hydroxybenzyl)ergothioneineGastrolatathioneine

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Sequential Ir-Catalyzed Allylation/2-aza-Cope Rearrangement Strategy for the Construction of Chiral Homoallylic Amines

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Chinese Journal of Chemistry 2020年第8期38卷 807-811页

作者： Ruo-Qing wang Chong Shen Xiang cheng Zuo-Fei wang Hai-Yan Tao Xiu-Qin Dong Chun-Jiang wang Engineering Research Center of Organosilicon Compounds&Materials Ministry of EducationCollege of Chemistry and Molecular SciencesWuhan UniversityWuhanHubei 430072China State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 230021China

Sequential Ir-catalyzed asymmetric allylation/2-aza-Cope rearrangement of arylidene aminomalonates with allylic carbonates was successfully developed,and a variety of enantioenriched homoallylic amine derivatives were obtained in high yields with good chirality transfer and excellent E/Z-geometry control(up to 99%yield,96%ee).Compared with previous dual catalytic system established for this transformation,the current mono metal catalytic system provides a simpler and more practical protocol employing the readily available starting materials.

关键词： materials system starting

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