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Chinese Physics Letters 2014年第4期31卷 155-158页

作者： gao pei-feng wang xing-zhe Key Laboratory of Mechanics on Western Disaster and Environment (Ministry of Education) and College of Civil Engineering and Mechanics Lanzhou University Lanzhou 730000

Superconducting materials are always severely restricted in practical engineering applications due to their carrying- current degradation under mechanical loads. Based on Ekin＇s exponential model and Weibull＇s distribution func- tion, we propose an empirical degradation model for describing the mechanical deformation influence on the critical-current of Bi-based superconducting multi-filamentary composite tapes under axial loading. The critical currents of superconducting tapes depending on the axial strain are investigated analytically. It is shown that the predictions by the developed degradation model agree with the experimental data, in the processes of axial mechanical loading and unloading on the samples. The effect of the critical tension and compression damage strains on the normalized critical currents is also discussed.

关键词： CRITICAL currents MULTIFILAMENTARY superconductors WEIBULL distribution SUPERCONDUCTING tape COMPRESSION loads

IoT Empowered Early Warning of Transmission Line Galloping Based on Integrated Optical Fiber Sensing and Weather Forecast Time Series Data

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Computers, Materials & Continua 2025年第1期82卷 1171-1192页

作者： zhe Li Yun Liang Jinyu wang Yang gao State Grid Henan Electric Power Company Electric Power Scientific Research Institute State Grid Henan Electric Power CompanyZhengzhou450052China

Iced transmission line galloping poses a significant threat to the safety and reliability of power systems,leading directly to line tripping,disconnections,and power *** early warning methods of iced transmission line galloping suffer from issues such as reliance on a single data source,neglect of irregular time series,and lack of attention-based closed-loop feedback,resulting in high rates of missed and false *** address these challenges,we propose an Internet of Things(IoT)empowered early warning method of transmission line galloping that integrates time series data from optical fiber sensing and weather ***,the method applies a primary adaptive weighted fusion to the IoT empowered optical fiber real-time sensing data and weather forecast data,followed by a secondary fusion based on a Back Propagation(BP)neural network,and uses the K-medoids algorithm for clustering the fused ***,an adaptive irregular time series perception adjustment module is introduced into the traditional Gated Recurrent Unit(GRU)network,and closed-loop feedback based on attentionmechanism is employed to update network parameters through gradient feedback of the loss function,enabling closed-loop training and time series data prediction of the GRU network ***,considering various types of prediction data and the duration of icing,an iced transmission line galloping risk coefficient is established,and warnings are categorized based on this ***,using an IoT-driven realistic dataset of iced transmission line galloping,the effectiveness of the proposed method is validated through multi-dimensional simulation scenarios.

关键词： Optical fiber sensing multi-source data fusion early warning of galloping time series data IoT adaptive weighted learning irregular time series perception closed-loop attention mechanism

Recent Advances in Fibrous Materials for Hydroelectricity Generation

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Nano-Micro Letters 2025年第2期17卷 109-133页

作者： Can Ge Duo Xu Xiao feng xing Yang zheheng Song Yuhang Song Jingyu Chen Yingcun Liu Chong gao Yong Du zhe Sun Weilin Xu Jian Fang College of Textile and Clothing Engineering Soochow UniversitySuzhou 215123People’s Republic of China National Engineering Laboratory for Modern Silk Soochow UniversitySuzhou 215123People’s Republic of China State Key Laboratory of New Textile Materials and Advanced Processing Technologies Wuhan Textile UniversityWuhan 430200People’s Republic of China Institute of Functional Nano&Soft Materials(FUNSOM) Soochow UniversitySuzhou 215123People’s Republic of China Department of Electrical and Computer Engineering University of MassachusettsAmherstMA 01003USA Department of Materials Imperial College LondonSouth Kensington CampusLondon SW72AZUK College of Textile Science and Engineering Zhejiang Sci-Tech UniversityHangzhou 310018People’s Republic of China School of Materials Science and Engineering Shanghai Institute of Technology100 Haiquan RoadShanghai 201418People’s Republic of China

Depleting fossil energy sources and conventional polluting power generation pose a threat to sustainable *** generation from ubiquitous and spontaneous phase transitions between liquid and gaseous water has been considered a promising strategy for mitigating the energy *** materials with unique flexibility,processability,multifunctionality,and practicability have been widely applied for fibrous materials-based hydroelectricity generation(FHG).In this review,the power generation mechanisms,design principles,and electricity enhancement factors of FHG are first ***,the fabrication strategies and characteristics of varied constructions including 1D fiber,1D yarn,2D fabric,2D membrane,3D fibrous framework,and 3D fibrous gel are ***,the advanced functions of FHG during water harvesting,proton dissociation,ion separation,and charge accumulation processes are analyzed in ***,the potential applications including power supply,energy storage,electrical sensor,and information expression are also ***,some existing challenges are considered and prospects for future development are sincerely proposed.

关键词： Hydroelectricity Fibrous material Streaming potential Ion diffusion

Effect of order–disorder transition on thermodynamic and electronic properties of σ and χ phases in W–Re alloy: the first-principles calculation

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Tungsten 2025年第1期 195-213页

作者： Zhi-Peng Zhu Dian Jia William Yi wang Jun-Lei Yin xing-Yu gao Shu-feng Yang Hai-feng Song Jin-Shan Li State Key Laboratory of Solidification Processing Northwestern Polytechnical University Laboratory of Computational Physics Institute of Applied Physics and Computational Mathematics School of Metallurgical and Ecological Engineering University of Science and Technology Beijing

The Tungsten-Rhenium(W-Re) alloys,celebrated for their high melting point,strength at elevated temperatures,electrical resistivity,and radiation resistance,have been widely utilized in high-temperature components,aerospace,electronics,and nuclear *** constituents of the topologically close-packed(TCP) phases,the sigma phase(σ) and chi phase(χ) formed within W-Re alloys wield considerable influence on the mechanical properties and the stability of the *** calculations were utilized in the present work to explore the structural,thermodynamic,and electronic properties of both ordered and disordered configurations within the σ and χ phases,culminating in a systematic elucidation of the higher phase stability exhibited by the ordered *** is found that the bulk modulus of these two phases is directly proportional to the concentration of Re in the alloy,while the equilibrium volume is inversely *** thermodynamic parameters of the σ and χ phases are calculated via the mean-field potential *** similar trends observed in the isobaric heat capacity,enthalpy increment,and entropy change curves for these two phases suggest they possess comparable thermodynamic *** is noteworthy that the contribution of ionic vibrations predominantly affects the isobaric heat capacity,while the contribution of thermal electronic excitations increases linearly with *** the structure and thermodynamic properties of TCP phases in W-Re alloys at low temperatures has profound significance for optimizing material performance,microstructures features,establishing theoretical foundations,and predicting material behavior.

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Technology diffusion and population migration reflected in blade technologies in northern China in the Late Pleistocene

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Science China Earth Sciences 2016年第8期59卷 1540-1553页

作者： LI feng CHEN FuYou wang YingHua gao xing Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China Inner Mongolia Museum Hohhot 010010 China

In recent years, the origin and evolution of modern human behaviors have become a common topic of research in Paleolithic archaeology. One important part of modern human behavior, blade technology, was once thought to be unique to modern humans. Recent studies have suggested that variations in blade technology do not fully correspond to modern populations. However, the standardization, diversity, discontinuity in terms of time distribution, and differences in spatial distribution of blade technology give it an important role in discussions of modes of adaptation, diffusion of technology, and population migration of hominins. By categorizing the major blade assemblages in China, we show that there were two blade reduction methods in northern China: the Levallois method and the prismatic method. Dating back 40000–30000 years, the Levallois and prismatic blade method combined to form the characteristics of the early stage of the Upper Paleolithic. Artifacts bearing such characteristics are located in Northwest China, Northeast China, and the Qinghai-Tibet Plateau. The unearthed blades are similar in technological organization and are connected geographically with those discovered in Siberia and Mongolia, which also indicates a distinct border from those discovered in northern China. This fact is suggestive of population immigration. About 29000–25000 years ago, a combination of prismatic blades and microblades was developed in the hinterland of China; however whether it can be regarded as the representative of population migration or only a technological adaption remains undetermined. We suggest that the system of production of different blades should be distinguished in the study of blade assemblages and that different blade methods should not be integrated into a single technical system to discuss technology diffusion and population dispersal.

关键词： North China Late Pleistocene Blade technology Technology diffusion Human migration

Analysis of sedimentary-geomorphologic variation and the living environment of hominids at the Shuidonggou Paleolithic site

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Chinese Science Bulletin 2008年第13期53卷 2025-2032页

作者： gao xing YUAN BaoYin pei ShuWen wang HuiMin CHEN FuYou feng xingWu Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Institute of Archeology of Ningxia Hui Autonomous Region Yinchuan 750001 China

Shuidonggou is one of the most important Upper Paleolithic sites in North China. Due to the presence of rich human remains,animal fossils,abundant sporopollen and unique geological sequence,it is the type site for Late Pleistocene to Holocene human occupation and environmental change in the Ningxia-Inner Mongolia region. Many scholars suggest that the site should be named the "Shuidong-gou Formation" of Late Pleistocene in North China. Dating results indicate that ancient human activities at the site took place 30―24 ka (Marine Isotope Stage MIS 3). The climate at that time was warmer and moister than present day,and adequate precipitation led to the formation of water pack depressions where broad-leaf trees and sparse forest vegetations,as well as herbivorous animals flourished,mak-ing the area suitable for early human hunting,gathering and survival. The Neolithic human occupation happened 9―5 ka at the site,while similar environmental conditions with MIS3 occurred. The absence of human activity record in the region during the Last Glacial Maximum (MIS2) suggests that the envi-ronment was too harsh for humans to live there.

关键词：居住环境旧石器时代古环境人种

The influence of the observational strategies of pulsar timing on the properties of pulsar clocks

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Research in Astronomy and Astrophysics 2020年第12期20卷 323-329页

作者： zhe-Hao Zhang Ming-Lei Tong Cheng-Shi Zhao xing-Zhi Zhu feng gao National Time Service Center Chinese Academy of SciencesXi’an 710000China Key Laboratory of Time and Frequency Primary Standard Chinese Academy of SciencesXi’an 710600China University of Chinese Academy of Sciences Beijing 100049China Department of Applied Physics Xi’an University of Science and TechnologyXi’an 710054China

Pulsars are very stable spinning stars, which have the potential to application in the work of time-keeping and autonomous navigation in deep space. For time application, an individual pulsar can be regarded as a clock. The accuracy and stability of a pulsar clock are mainly determined by various timing noises and the measurement errors;however, they would be affected by the concrete observational *** four millisecond pulsars from the first data released by International Pulsar Timing Array(IPTA) as an example, we investigated the influences of different observational strategies on the properties of pulsar clocks by removing some data in various ways. We find that the long-term stabilities of pulsar clocks are nearly not affected by increasing the observational cadence with a fixed time span. It is also found that the capabilities of prediction by pulsar clocks are also hardly affected by different observational strategies,which is reflected by both the stable weighted root-mean-square(wrms) and the stability of the resulting pre-fit timing residuals, unless the data span is too short or the data period is too far from the start of prediction.

关键词： methods:data analysis time pulsars:general

Autophagy and skin wound healing

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Burns & Trauma 2022年第1期10卷 757-767页

作者： Haiyue Ren feng Zhao Qiqi Zhang xing Huang zhe wang Department of Pathology Shengjing Hospital of China Medical University36 Sanhao StreetHeping DistrictShenyang City 110004Liaoning ProvinceChina Department of Stem Cells and Regenerative Medicine Shenyang Key Laboratory of Stem Cell and Regenerative MedicineChina Medical UniversityShenyang 110013LiaoningChina Department of General Surgery Shengjing Hospital of China Medical University36 Sanhao StreetHeping DistrictShenyang City 110004Liaoning ProvinceChina

Autophagy is a lysosome-dependent,self-renewal mechanism that can degrade and recycle cellular components in eukaryotic cells to maintain the stability of the intracellular environment and the cells ability to cope with unfavorable *** studies suggest that autophagy participates in regulating various cellular functions and is closely associated with the onset and progression of various *** healing is a complex,multistep biological process that involves multiple cell *** wounds,which include diabetic skin ulcers,can seriously endanger human *** studies have confirmed that autophagy plays an essential role in various phases of wound ***,in the inflammatory phase,autophagy has an anti-infection effect and it negatively regulates the inflammatory response,which prevents excessive inflammation from causing tissue *** the proliferative phase,local hypoxia in the wound can induce autophagy,which plays a role in anti-apoptosis and anti-oxidative stress and promotes cell *** of vascular endothelial cells promotes wound angiogenesis and that of keratinocytes promotes their differentiation,proliferation and migration,which is conducive to the completion of wound *** the remodeling phase,autophagy of fibroblasts affects the formation of hypertrophic ***,a refractory diabetic wound may be associated with increased levels of autophagy,and the regulation of mesenchymal stem cell autophagy may improve its application to wound ***,understanding the relationship between autophagy and skin wound healing and exploring the molecular mechanism of autophagy regulation may provide novel strategies for the clinical treatment of wound healing.

关键词： Autophagy Wound healing Diabetes Mesenchymal stem cells microRNA Skin

Surgical therapy for hemangioma of the azygos vein arch under thoracoscopy: A case report

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World Journal of Clinical Cases 2021年第11期9卷 2655-2661页

作者： zhen-xing wang Liang-Liang Yang zhe-Nan Xu pei-Yun Lv Yue wang Department of Thoracic Surgery China-Japan Union Hospital of Jilin UniversityChangchun 130033Jilin ProvinceChina

BACKGROUND Azygos vein aneurysms are extremely rare,and their pathogenesis is not *** overwhelming majority of patients have no obvious clinical symptoms and are found to have the disease by physical examination or by *** are few reports on the diagnosis of and treatment strategy for this ***,the choice of therapeutic schedule and the treatment window are *** SUMMARY We report a case of azygos vein arch aneurysm in a 53-year-old *** patient had symptoms of back pain,chest tightness,and *** chest computed tomography showed a soft-tissue mass in the right posterior mediastinum,which was connected to the superior vena *** enhancement degree in the venous phase was the same as that of the superior vena *** patient received video-assisted thoracoscopic *** the operation,her back pain disappeared,and her dysphagia and chest tightness were also significantly *** postoperative pathology confirmed *** patient was discharged on the seventh day after surgery without any *** Some patients with hemangioma of the azygos vein arch may experience dysphagia and chest tightness caused by the tumor compressing the esophagus and *** computed tomography scanning is vital for the diagnosis of azygos vein *** addition,despite the difficulty and risk of surgery,thoracoscopic surgery for azygos vein aneurysms is completely feasible.

关键词： Azygos vein aneurysm Hemangioma of the azygos vein arch Mediastinal tumor Thoracoscopic surgery Case report

Effect of lanthanum addition on microstructure and hardness of brass alloys produced by rheological squeeze casting

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Journal of Rare Earths 2022年第12期40卷 1953-1962,I0006页

作者： Wenjing gao Shuming xing Ying wang School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China School of Mechatronics and Vehicle Engineering Zhengzhou University of TechnologyZhengzhou 450044China

The effect of La addition(0-0.30 wt%)on the microstructure and hardness of rheological squeeze casting brass alloys was experimentally *** rheological squeeze casting process is improved by controlling the wall surface crystals and melt flow rate to realise the preparation of semi-solid melt with flow,and a brass alloy workpiece with La is *** microstructure and properties of the brass alloy samples were investigated using metallography,scanning electron microscopy,energy-dispersive X-ray spectroscopy,X-ray diffraction and hardness *** results indicate that the hardness of the rheological squeeze casting brass alloy is increased by 20.4%from 108 to 130 HBW with an increase in the La content from 0 to 0.30 wt%.The micro structural analysis results show that La significantly refines the primary a-phase grains,and the main mechanism is the constitutional undercooling and heterogeneous nucleation caused by the La enrichment in the front of the solid-liquid *** squeeze pressure promotes undercooling,which improves the nucleation rate and affects the solute diffusion and nucleus *** dual effects of these two aspects aggravate the grain refinement process,consequently increasing the number of grain boundaries and improving the hardness of the brass alloy.

关键词： Rheological squeeze casting La Brass alloy Grain refinement Rare earths