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Reliability of DC-link capacitor in pulsed power supply for accelerator magnet

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Nuclear Science and Techniques 2024年第9期35卷 28-40页

作者： Jie Wang Da-qing Gao Wan-Zeng Shen Hong-Bin yan Li-Jun Mao Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology Lanzhou UniversityLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China

Capacitors are widely used in pulsed magnet power supplies to reduce ripple voltage,store energy,and decrease power *** this study,DC-link capacitors in pulsed power supplies were *** deriving an analytical method for the capacitor current on the H-bridge topology side,the root-mean-square value of the capacitor current was calculated,which helps in selecting the DC-link *** proposed method solves this problem quickly and with high *** current reconstruction of the DC-link capacitor is proposed to avoid structural damage in the capacitor’s current measurement,and the capacitor’s hotspot temperature and temperature rise are calculated using the FFT *** test results showed that the error between the calculated and measured temperature increases was within 1.5℃.Finally,the lifetime of DC-link capacitors was predicted based on Monte Carlo *** proposed method can evaluate the reliability of DC-link capacitors in a non-isolated switching pulsed power supply for accelerators and is also applicable to film capacitors.

关键词： Aluminum electrolytic capacitor DC-link current DC–DC power converter Hotspot temperature

Experimental investigation into the salinity effect on the physicomechanical properties of carbonate saline soil

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第5期16卷 1883-1895页

作者： Jiejie Shen qing Wang Yating Chen Xuefei Zhang yan Han Yaowu Liu College of Construction Engineering Jilin UniversityChangchun130026China Shandong Zhengyuan Geological Resources Exploration Co.Ltd. Jinan250013China China Renewable Energy Engineering Institute Beijing100120China

For engineering structures with saline soil as a filling material,such as channel slope,road subgrade,etc.,the rich soluble salt in the soil is an important potential factor affecting their safety *** study examines the Atterberg limits,shear strength,and compressibility of carbonate saline soil samples with different NaHCO3 contents in Northeast *** mechanism underlying the influence of salt content on soil macroscopic properties was investigated based on a volumetric flask test,a mercury intrusion porosimetry(MIP)test,and a scanning electron microscopic(SEM)*** results demonstrated that when NaHCO3 contents were lower than the threshold value of 1.5%,the bound water film adsorbed on the surface of clay particles thickened continuously,and correspondingly,the Atterberg limits and plasticity index increased rapidly as the increase of sodium ion ***,the bonding force between particles was weakened,the dispersion of large aggregates was enhanced,and the soil structure became ***,the compressibility increased and the shear strength(mainly cohesion)decreased by 28.64%.However,when the NaHCO3 content exceeded the threshold value of 1.5%,the salt gradually approached solubility and filled the pores between particles in the form of crystals,resulting in a decrease in soil *** cementation effect generated by salt crystals increased the bonding force between soil particles,leading to a decrease in plasticity index and an improvement in soil mechanical ***,this work provides valuable suggestions and theoretical guidance for the scientific utilization of carbonate saline soil in backfill engineering projects.

关键词： Carbonate saline soil Salt content Physicomechanical properties Bound water Microstructure

Retrieval of Antarctic sea ice freeboard and thickness from HY-2B satellite altimeter data

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Acta Oceanologica Sinica 2024年第3期43卷 87-101页

作者： Yizhuo Chen Xiaoping Pang qing Ji Zhongnan yan Zeyu Liang Chenlei Zhang Chinese Antarctic Center of Surveying and Mapping Wuhan UniversityWuhan 430079China Key Laboratory of Polar Surveying and Mapping Science Ministry of Natural ResourcesWuhan 430079China Key Laboratory of Polar Environment Monitoring and Public Governance Ministry of EducationWuhan 430079China 4 School of Geography and Tourism Anhui Normal UniversityWuhu 241002China

Antarctic sea ice is an important part of the Earth’s atmospheric system,and satellite remote sensing is an important technology for observing Antarctic sea *** Chinese Haiyang-2B(HY-2B)satellite altimeter data could be used to estimate sea ice freeboard and provide alternative Antarctic sea ice thickness information with a high precision and long time series,as other radar altimetry satellites can,needs further *** paper proposed an algorithm to discriminate leads and then retrieve sea ice freeboard and thickness from HY-2B radar altimeter *** first collected the Moderate-resolution Imaging Spectroradiometer ice surface temperature(IST)product from the National Aeronautics and Space Administration to extract leads from the Antarctic waters and verified their accuracy through Sentinel-1 Synthetic Aperture Radar ***,a surface classification decision tree was generated for HY-2B satellite altimeter measurements of the Antarctic waters to extract leads and calculate local sea surface *** then estimated the Antarctic sea ice freeboard and thickness based on local sea surface heights and the static equilibrium ***,the retrieved HY-2B Antarctic sea ice thickness was compared with the CryoSat-2 sea ice thickness and the Antarctic Sea Ice Processes and Climate(ASPeCt)ship-based observed sea ice *** results indicate that our classification decision tree constructed for HY-2B satellite altimeter measurements was reasonable,and the root mean square error of the obtained sea ice thickness compared to the ship measurements was 0.62 *** proposed sea ice thickness algorithm for the HY-2B radar satellite fills a gap in this application domain for the HY-series satellites and can be a complement to existing Antarctic sea ice thickness products;this algorithm could provide long-time-series and large-scale sea ice thickness data that contribute to research on global climate change.

关键词： HY-2B satellite altimeter classification decision tree sea ice freeboard and thickness Antarctic waters

Liposomalα-cyperone targeting bone resorption surfaces suppresses osteoclast differentiation and osteoporosis progression via the PI3K/Akt axis

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Nano Research 2024年第4期17卷 2949-2959页

作者： Lin yang Xueying An Wang gong Wenshu Wu Bin Liu Xiaoyan Shao yansi Xian Rui Peng Baosheng Guo qing Jiang Division of Sports Medicine and Adult Reconstructive Surgery Department of Orthopedic SurgeryNanjing Drum Tower Hospital Clinical College of Nanjing Medical University321 Zhongshan RoadNanjing 210008China Branch of National Clinical Research Center for Orthopedics Sports Medicine and RehabilitationNanjing 210008China State Key Laboratory of Pharmaceutical Biotechnology Medical SchoolNanjing University&Division of Sports Medicine and Adult Reconstructive SurgeryDepartment of Orthopedic SurgeryNanjing Drum Tower HospitalThe Affiliated Hospital of Nanjing University Medical SchoolNanjing 210008China

Osteoporosis is a metabolic dysregulation of bone that occurs mainly in postmenopausal women,and the hyperfunction of osteoclasts is the primary contributor to postmenopausal ***,the development of effective therapeutic drugs and precise delivery systems remains a challenge in the field of anti-absorption ***,we reported theα-cyperone(α-CYP)for anti-osteoporosis and developed a liposome-based nano-drug delivery system ofα-CYP,that specifically targets the bone resorption ***,we found that theα-CYP,one of the major sesquiterpenes of Cyperus rotundus L.,attenuated the progression of osteoporosis in ovariectomized(OVX)mice and down-regulated the expression of phosphorylated proteins of phosphoinositide 3-kinase(PI3K)and protein kinase B(Akt),causing down-regulation of osteoclast-related genes/proteins and curbing osteoclast ***,α-CYP reversed the activation of osteoclastic differentiation and enhanced osteoporosis-related proteins expression caused by PI3K/Akt agonist(YS-49).More importantly,we adopted the osteoclastic resorption surface targeting peptide Asp8 and constructed the liposome(lipαC@Asp8)to deliverα-CYP to osteoclasts and confirmed its anti-osteoporosis effect and enhanced osteoclast inhibition by blocking PI3K/Akt *** conclusion,this study demonstrated thatα-CYP inhibits osteoclast differentiation and osteoporosis development by silencing PI3K/Akt pathway,and the liposome targeting delivery systems loaded withα-CYP might provide a novel and effective strategy to treat osteoporosis.

关键词： osteoporosis α-cyperone osteoclast phosphoinositide 3-kinase/protein kinase B(PI3K/Akt) liposome

Investigation of Power Density Amplification in Stacked Triboelectric Nanogenerators

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Energy & Environmental Materials 2024年第5期7卷 372-379页

作者： Fan Shen Qin Zhang Hengyu Guo Chen Cao Ying gong Junlei Wang yan Peng Zhongjie Li School of Mechatronic Engineering and Automation Shanghai University Department of Applied Physics Chongqing University Institute of Artificial Intelligence School of Future Technology Shanghai University School of Mechanical and Power Engineering Zhengzhou University Shanghai Artificial Intelligence Laboratory

In engineering practice, the output performance of contact separation TENGs(CS-TENGs) increases with the increase of tribo-pair area, which includes increasing the size of single layer CS-TENGs (SCS-TENGs) or the number of units (zigzag TENGs). However, such two strategies show significant differences in output power and power density. In this study, to seek a universal CS-TENG design solution, the output performance of a SCS-TENG and a zigzag TENG (Z-TENG) is systematically compared, including voltage,current, transferred charge, instantaneous power density, and charging power density. The relationship between contact area and output voltages is explored, and the output voltage equation is fitted. The experimental results reveal that SCS-TENGs yield better performance than Z-TENGs in terms of voltage, power, and power density under the same total contact area.

关键词： contact separation power density triboelectric nanogenerators zigzag

Cross-linked Electrospun Gel Polymer Electrolytes for Lithium-Ion Batteries

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Chinese Journal of Polymer Science 2024年第8期42卷 1021-1028页

作者： Xue gong Qin Xiao qing-Yin Li Wen-Cui Liang Feng Chen Long-Yu Li Shi-Jie Ren College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China

Lithium-ion batteries(LIBs)benefit from an effective electrolyte system design in both terms of their safety and energy storage ***,a series of precursor membranes with high porosity were produced using electrospinning technology by mixing PVDF and triblock copolymer(PS-PEO-PS),resulting in a porous structure with good interconnections,which facilitates the absorbency of a large amount of electrolyte and further increases the ionic conductivity of gel polymer electrolytes(GPEs).It has been demonstrated that post-cross-linking of the precursor membranes increa ses the rigidity of the nanofibers,which allows the polymer film to be dimensionally sta ble up to 260℃while maintaining superior electrochemical *** obtained cross-linked GPEs(CGPEs)showed high ionic conductivity up to 4.53×10^(-3)S·cm^(-1).With the CGPE-25,the assembled Li/LiFeP04 half cells exhibited good rate capability and maintained a capacity of 99.4%and a coulombic efficiency of99.3%at 0.1 *** results suggest that the combination of electrospinning technique and post-cross-linking is an effective method to construct polymer electrolytes with high thermal stability and steadily decent electrochemical performance,particularly useful for Lithium-ion battery applications that require high-temperature usage.

关键词： Electrospinning Cross-linked Gel polymer electrolytes Lithium-ion batteries

Celastrus orbiculatus Extract Inhibits Immune Inflammatory Thrombotic State of B-Lymphoma

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Chinese Journal of Integrative Medicine 2024年第11期30卷 1018-1026页

作者： ZHU Miao SHI qing-qing NI Jun WU Wei SUN Xing SUN Mei XU Kai-lin LIU yan-qing GU Jian GU Hao Department of Hematology Clinical Medical Col ege Yangzhou University yangzhou Institute of Hematology Department of Hematology The Affiliated Hospital of Xuzhou Medical University Department of Oncology The Affiliated Hospital of Yangzhou University Yangzhou University Department of Neurology The Affiliated Brain Hospital of Nanjing Medical University

Objective:To investigate the inhibitory effect of Celastrus orbiculatus extracts（COE） on the proliferation of lymphoma cells and the immune regulation ability on inflammation and thrombophilia in ***:The 38B9 lymphoma cells were treated with COE（160μg/mL） and CTX（25 μmol/L）.The apoptosis rate and cell cycle of each group were detected by flow *** secretion of inflammatory factors,including interleukin（IL）-6,IL-10,and tumor necrosis factor α（TNF-α）,in cell supernatant was detected by enzyme-linked immunosorbent assay（ELISA）.In vivo,BALB/c mice were subcutaneously injected with 38B9 lymphoma cells to establish lymphoma ***(3 mg·kg-1·d-1) and CTX(40 mg-kg-1·d-1) were administered to the model mice,*** expression of plasma inflammatory factors（IL-6,IL-10 and TNF-α） and thrombus indexes,including D-dimer（D-D）,von Willebrand factor（vWF） and tissue factor（TF）,were detected by ELISA before tumor bearing（1 d）,after tumor formation（14 d） and after intervention（21 d）.PicoGreen dsDNA was used to detect the level of serum neutrophil extracellular traps（NETs）.Flow cytometry was used to detect the expression of platelet activation marker calcium-dependent lectin-like receptor 2（CLEC-2）.The tumor growth and survival of mice were ***:The 38B9 lymphoma cells were apoptotic after the intervention of COE and *** ratio of G2-M phase cells decreased in COE intervented cells compared with the control cells（P<0.05）,and S phase cells decreased in CTX intervented cells（P<0.05）.Also,the secretion level of IL-6 was significantly reduced after COE or CTX intervention（P<0.05）,and IL-10 was significantly increased（P<0.05）.Furthermore,the tumor mass was reduced,and the median survival time was longer in COE and CTX intervented tumor-bearing mice than in nonintervented *** significantly lower levels of TNF-α,IL-6,NETs,TF,DD and CLEC-2,as well as higher IL-10 were observed in COE and CTX treatment mice in comparision with the control mice（P

关键词： Celastrus orbiculatus extract immune regulation lymphoma murine lymphoma cells proliferation inhibition thrombotic state tumor inflammation

Astrometric Observations of NEA 1998 HH49 Using the Daocheng 50 cm Telescope

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Research in Astronomy and Astrophysics 2024年第7期24卷 71-78页

作者： Huan Xu Xiang-Ming Cheng Yi-gong Zhang Teng-Fei Song Zhen-Jun Zhang qing-Yu Peng Yunnan Observatories Chinese Academy of SciencesKunming 650216China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of the Structure and Evolution of Celestial Objects Chinese Academy of SciencesKunming 650216China Engineering Laboratory on Applied Astronomical Technology of Yunnan Kunming 650216China School of Information Engineering Kunming UniversityKunming 650214China School of Computer Science and Information Engineering Anyang Institute of TechnologyAnyang 455000China Department of Computer Science Jinan UniversityGuangzhou 510632China Sino-French Joint Laboratory for Astrometry Dynamics and Space ScienceJinan UniversityGuangzhou 510632China

This study details an astrometric observation campaign of the Near-Earth Asteroid 1998 HH49,conducted with the aim of refining our understanding of its physical *** the 50 cm telescope located at the Wumingshan Mountain in Daocheng,Sichuan,images were obtained over four nights,from 2023 October 19 to October *** observations were processed using Astrometrica software,facilitating the precise determination of the asteroid's *** observational results were compared with the ephemerides from three distinct sources to verify accuracy:the Jet Propulsion Laboratory(JPL)Horizons System,the Institut de Mécanique Céleste et de Calcul deséphémérides(IMCCE)Miriade,and the Near-Earth Objects Dynamic Site(NEODyS-2).When compared with the JPL ephemeris,a mean observed-minus-calculated(O-C)result of 0.″07 in the *** and-0.″35 in the *** was ***,the comparison with the IMCCE ephemeris yielded mean O-C results of 0.″08 in the *** and-0.″06 in the *** comparison with the NEODyS-2 ephemeris yielded the mean O-C results of 0.″06 in ***-0.″49 in *** study's findings demonstrate a general consistency between the observed data and the ephemeris predictions,with minor discrepancies observed across the data ***,both the JPL and NEODyS-2 ephemerides show that the residuals in the *** exceed those in the *** disparities may result from atmospheric differential color refraction,ephemeris discrepancies,observational errors,and other ***,it is worth noting that further investigation is required due to the potential influence of additional ***,the Daocheng 50 cm Telescope exhibits the ability to conduct high-precision positional measurements.

关键词： astrometry ephemerides time

Multiple damage zones around hydraulic fractures generated by high-frequency pulsating hydraulic fracturing

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Petroleum Science 2024年第4期21卷 2688-2702页

作者： yan Peng Sheng-Jie Wei Guang-qing Zhang Da-Wei Zhou Chuang-Chao Xu School of Petroleum Engineering China University of Petroleum PetroChina Changqing Oilfield Company

Pulsating hydraulic fracturing(PHF) is a promising fracturing method and can generate a dynamic periodic pressure. The periodic pressure can induce fatigue failure of rocks and decrease initiation pressure of fracture. If the frequency of periodic pressure exceeds 10 Hz, the distribution of pressure along the main fracture will be heterogeneous, which is much different from the one induced by the common fracturing method. In this study, the impact of this special spatial feature of pressure on hydraulic fracture is mainly investigated. A coupled numerical simulation model is first proposed and verified through experimental and theoretical solutions. The mechanism of secondary fracture initiation around the main fracture is then discovered. In addition, sensitivity studies are conducted to find out the application potential of this new method. The results show that(1) this coupled numerical simulation model is accurate. Through comparison with experimental and theoretical data, the average error of this coupled model is less than 1.01%.(2) Even if a reservoir has no natural fracture, this heterogeneous distribution pressure can also cause many secondary fractures around the main fracture.(3) The mechanism of secondary fracture initiation is that this heterogeneous distribution pressure causes tensile stress at many locations along the main fracture.(4) Through adjusting the stimulation parameters, the stimulation efficiency can be improved. The average and amplitude of pressure can increase possibility of secondary fracture initiation. The frequency of this periodic pressure can increase number of secondary fractures. Even 6 secondary fractures along a 100 m-length main fracture can be generated.(5) The influence magnitudes of stimulation parameters are larger than ones of geomechanical properties, therefore, this new fracturing method has a wide application potential.

关键词： Tight reservoir Reservoir stimulation Numerical simulation Secondary fracture Fracture initiation