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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

Effect of Iron on the Stability of Rhodochrosite at the Topmost Lower Mantle Conditions

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Journal of Earth Science 2024年第2期35卷 504-513页

作者： Tianlei Zhai Fei qin Shengxuan Huang Shan qin Yu gong Key Laboratory of Orogenic Belts and Crustal Evolution Ministry of EducationSchool of Earth and Space SciencesPeking UniversityBeijing100871China School of Earth Sciences and Resources China University of GeosciencesBeijing100083China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of SciencesBeijing100049China

Carbonates are viewed as the principal oxidized carbon carriers during subduction,and thus the stability of subducted carbonates has significant implications for the deep carbon *** we investigate the high pressure-temperature behaviors of rhodochrosite in the presence of iron up to∼34 GPa by in-situ X-ray diffraction and ex-situ Raman *** relatively low temperature below∼1500 K,MnCO_(3)breaks down into MnO and CO_(2).Upon heating to∼1800 K,however,the MnCO_(3)-Fe^(0)reactions occur with the formation of Mn_(3)O_(4),Fe^(O)and reduced carbon.A'three-stage'reaction mechanism is proposed to understand the kinetics of the carbon-iron-manganese redox *** results suggest that Fe^(0)can serve as a reductant to greatly affect the stability of rhodochrosite,which implies that the effect of Fe-metal should be seriously considered for the high pressure-temperature behaviors of other predominant carbonates at Earth's mantle conditions,particularly at depths greater than∼250 km.

关键词： deep carbon cycle rhodochrosite reduced mantle diamond formation high pressure tectonics geochemistry

Cervical aortic arch with aneurysm formation and an anomalous right subclavian artery and left vertebral artery:A case report

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World Journal of Clinical Cases 2022年第10期10卷 3291-3296页

作者： Yao-Kun Wu Qi Mao Mao-Ting Zhou Ning Liu Xi Yu Jin-Cheng Peng Yun-Yun Tao xue-qin gong Lin Yang Xiao-Ming Zhang Medical Imaging Key Laboratory of Sichuan Province Nanchong 637000Sichuan ProvinceChina Medical Research Center Department of RadiologyThe Affiliated Hospital of North Sichuan Medical CollegeNanchong 637000Sichuan ProvinceChina

BACKGROUND A cervical aortic arch(CAA)refers to a high-riding aortic arch(AA)that often extends above the level of the *** condition is very rare,with an incidence of less than 1/*** SUMMARY A 29-year-old woman was admitted to the otolaryngology department of our hospital for repeated bilateral purulent nasal discharge for the prior 3 *** patient was diagnosed with chronic sinusitis and chronic rhinitis at admission.A preoperative noncontrast chest computed tomography scan showed a high-riding,tortuous AA extending to the mid-upper level of the first thoracic vertebra with local cystic dilatation.A further computed tomography angiography examination showed that the brachiocephalic trunk,left common carotid artery,left vertebral artery(LVA)(slender),and left subclavian artery sequentially branched off of the aorta from the proximal end to the distal end of the *** proximal end of the right subclavian artery(RSCA)was tortuous and *** AA showed tumorlike local expansion,with a maximum diameter of approximately 4 *** consultation with the department of cardiac macrovascular surgery,the patient was diagnosed with left CAA with aneurysm formation and an anomalous RSCA and LVA and was transferred to that *** patient underwent AA aneurysm resection and artificial blood vessel replacement under general anesthesia and cardiopulmonary *** abnormality was found during the 2-mo follow-up after *** A CAA is a rare congenital anomaly of vascular *** present unique case of CAA with aneurysm formation and an anomalous RSCA and LVA enriches existing CAA data.

关键词： Cervical aortic arch Aortic aneurysm Aortic anomaly Computed tomography angiography Haughton classification Case report

Random Forest-Based Fatigue Reliability-Based Design Optimization for Aeroengine Structures

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Computer Modeling in Engineering & Sciences 2024年第7期140卷 665-684页

作者： xue-qin Li Lu-Kai Song School of Energy and Power Engineering Beihang UniversityBeijing100191China Department of Mechanical Engineering The Hong Kong Polytechnic UniversityKowloonHong Kong999077China Research Institute of Aero-Engine Beihang UniversityBeijing100191China

Fatigue reliability-based design optimization of aeroengine structures involves multiple repeated calculations of reliability degree and large-scale calls of implicit high-nonlinearity limit state function,leading to the traditional direct Monte Claro and surrogate methods prone to unacceptable computing efficiency and *** this case,by fusing the random subspace strategy and weight allocation technology into bagging ensemble theory,a random forest(RF)model is presented to enhance the computing efficiency of reliability degree;moreover,by embedding the RF model into multilevel optimization model,an efficient RF-assisted fatigue reliability-based design optimization framework is *** the low-cycle fatigue reliability-based design optimization of aeroengine turbine disc as a case,the effectiveness of the presented framework is *** reliabilitybased design optimization results exhibit that the proposed framework holds high computing accuracy and computing *** current efforts shed a light on the theory/method development of reliability-based design optimization of complex engineering structures.

关键词： Random forest reliability-based design optimization ensemble learning machine learning

Oxidation behavior of low-grade vanadiferous titanomagnetite concentrate with high titanium

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Journal of Iron and Steel Research International 2024年第2期31卷 329-341页

作者： Jin-sheng Liu Zhen-xing Xing gong-jin Cheng xue-yong Ding Xiang-xin xue School of Metallurgy Northeastern UniversityShenyang110819LiaoningChina Liaoning Key Laboratory of Recycling Science for Metallurgical Resources Shenyang110819LiaoningChina Innovation Research Institute of Vanadium and Titanium Resource Industry Technology Northeastern UniversityShenyang110819LiaoningChina

In order to clarify the oxidation mechanisms and make better use of the low-grade vanadiferous titanomagnetite concentrate with high titanium(LVTC),the oxidation behavior of LVTC was *** results showed that oxidation degree was achieved within 90 min when temperature was not lower than 700°C,and the main phases of the oxidized LVTC consisted of Fe9TiO15,Fe2O3,CaSiTiO5 and a small amount of *** temperature is favorable to the formation of *** surface of LVTC gradually becomes rough,with fine particles of needle-like and granular shape appearing on the surface,which finally turn from laminar to creamy,spread out,and are interspersed with many tiny *** phase oxidation paths in LVTC were as follows:(1)Fe2.75Ti0.25O4→Fe9TiO15+Fe2O3;(2)Fe2.75Ti0.25O4→Fe2O3+FeTiO3→Fe2TiO5;(3)FeTiO3→Fe2O3+Fe2Ti3O9→*** is predominantly mesoporous whether oxidized or not,with the pores mainly distributed in the range of 2–40 nm,and the specific surface area of LVTC decreases significantly with increasing temperature.

关键词： Low-grade vanadiferous titanomagnetite concentrate Oxidation degree Phase transformation Micromorphology Oxidation path Pore structure

Critical environmental factors affecting mountain geohazards in a warming climate in Southwest China

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Advances in Climate Change Research 2024年第4期15卷 695-707页

作者： Xiao-Ming XU Peng CUI xue-qin ZHANG Key Lab of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 10010lChina University of Chinese Academy of Sciences Beijing 100049China China-Pakistan Joint Research Center on Earth Sciences Chinese Academy of Sciences and Higher Education CommissionIslamabad 45320Pakistan

Environmental factors are essential input variables for susceptibility assessment models of mountain ***,the existing literature provides a limited understanding of the relative contribution of these factors to the occurrence of geohazards with a warming climate,posing tremendous challenges for risk management in mountainous ***'an city is susceptible to hazards because of its steep terrain,abundant precipitation and active seismic *** this regard,we utilise the GeoDetector model to extract critical environmental factors affecting the spatial patterns of mountain geohazards(i.e.,landslide,debris flow and rockfall)in Southwest *** analysis indicates that the factors with the highest explanatory power for the spatial distribution of landslides,debris flows,and rockfalls are soil property,extreme precipitation and extreme temperature,***,we revealed the synergistic effects among factors given their larger q-value than individual *** further explored the responses of mountain geohazards to climate change,including the rising temperature and precipitation,because the frequent occurrence of mountain geohazards is closely related to a warming *** variation in snow water equivalent caused by antecedent snowfall and snowdrifts acts as a crucial indicator for geohazards,highlighting the significance of snow and wind observations in meteorological nowcasting and disaster *** disclose the phenomenon of the geohazard hysteresis to the precipitation peak resulting from the top-down(i.e.,precipitation-runoff and surface-deep soil moisture)peak *** work is expected to enhance the precision of susceptibility assessment models and the reliability of short-term forecasts for mountain geohazards.

关键词： Mountain geohazards Environmental factors Climate change GeoDetector Southwest China

Rural labor migration and farmers’arrangements of rice production systems in Central China:Insight from the intergenerational division of labor

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Journal of Integrative Agriculture 2024年第9期23卷 3200-3214页

作者： xue Shen Quanyu Yang Rongjun Ao Shengsheng gong Key Laboratory for Geographical Process Analysis&Simulation of Hubei Province/College of Urban and Environmental Sciences Central China Normal UniversityWuhan 430079China

Rice production is crucial for food security in China,and its relationship with rural labor migration has been studied *** migration in rural China has taken new forms in recent *** has been a discernible trend wherein adult children have started migrating to cities while their elderly parents return to villages to re-engage in on-farm *** phenomenon has notably shaped the intergenerational division of labor(IDL)within ***,it remains to be seen how farmers adjust their rice production systems in response to the *** age of 60 years for employment injury insurance is the eligibility threshold for off-farm employment and is used to obtain a source of exogenous variation in the *** on a representative household survey of 1,752 rice farmers in the Hubei Province of Central China,our fuzzy regression discontinuity analysis reveals that farmers in IDL households are more likely to adopt ratoon rice(RR)than single cropping rice(SR)or double cropping rice(DR).The effect of the IDL varies under different levels of operational scales and specialized agricultural service *** analysis suggests that farmers’arrangements are associated with two potential mechanisms of downward intergenerational *** transfer for urban housing purchases increases RR in IDL households,and time transfer for intergenerational childcare significantly promotes SR in IDL *** study enhances the understanding of the relationship between rural labor migration and rice production in China,providing a reference for adjusting rice production systems to ensure food security.

关键词： labor migration intergenerational division of labor rice production systems fuzzy regression discontinuity Central China

Intensified warming suppressed the snowmelt in the Tibetan Plateau

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Advances in Climate Change Research 2024年第3期15卷 452-463页

作者： Xiang LI Peng CUI xue-qin ZHANG Fang ZHANG Key Lab of Land Surface Pattern and Simulation Institute of Geographic Sciences and Natural Resources ResearchBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China China‒Pakistan Joint Research Center on Earth Sciences Chinese Academy of Sciences and Higher Education CommissionIslamabad 45320Pakistan

Understanding how hydrological factors interrelate is crucial when examining the impact of climate warming on ***,these connections are often overlooked,leading to an unclear relationship between temperature and *** study investigates the complex interplay between temperature and snowmelt in the Tibetan Plateau from 1961 to 2020,focusing on how extreme high-temperature events affect the frequency of extreme *** a structural equation model,we detected three temperature-related factors that predominantly influenced snowmelt and extreme *** annual average temperature was found to have a significant indirect impact on snowmelt,mediated by changes in snowfall,snow depth and snow *** contrast,high-temperature days(daily maximum temperatures exceeding the 90th percentile)and heat waves(at least three consecutive high-temperature days)negatively affected extreme snowmelt directly or *** direct effect of increasing extreme temperature events was associated with an earlier onset of high-temperature periods,which accelerated snowmelt and shortened the duration of extreme snowmelt ***,the reduction in snow cover owing to warming emerged as a main factor suppressing snowmelt and extreme snowmelt *** also revealed spatiotemporal variations in the temperature‒snowmelt relationship that highly depended on changes in snowmelt *** study elucidated why warming suppresses snowmelt and extreme snowmelt events in the Tibetan Plateau,highlighting the mediating roles of snow-related and phenological *** findings will provide scientific support for climate simulation and water management policymaking in alpine regions worldwide.

关键词： Climate change Extreme temperature Snowmelt Structural equation model Tibetan Plateau

Experimental and numerical investigation of the impacts of rotor tip-rake on excitation forces of pump-jet propulsors

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Journal of Hydrodynamics 2024年第1期36卷 142-157页

作者： xue-qin Ji Xiao-song Zhang Chen-jun Yang Xiao-qian Dong State Key Laboratory of Ocean Engineering Marine Numerical Experiment CentreSchool of Naval ArchitectureOcean and Civil EngineeringShanghai Jiao Tong UniversityShanghai200240China CSSC Shanghai Marine Energy Saving Technology Co. Ltd.Shanghai200011China China Ship Scientific Research Center Shanghai Branch Shanghai200011China

The tip-clearance flow in a pump-jet propulsor exerts great impacts on the fluctuating pressures and resultant unsteady forces,which are important sources of structural vibrations and radiated noise *** blade geometry close to the tip is an important factor determining the vortex strength in the tip-clearance *** the open-water condition,the effects of raking the rotor tips on the duct-surface fluctuating pressures and the resultant unsteady forces acting on different components of the propulsor are investigated via physical model experiments and the numerical solution of Reynolds-averaged Navier-Stokes(RANS)equations coupled with the SST k-ωturbulence *** measured and simulated results of hydrodynamic pressures are consistent to each other,and the simulated flows help better understand why the fluctuating pressures change with the tip *** strong fluctuations of duct-surface pressures are caused by intensive tip separation *** duct-surface pressure fluctuations are effectively reduced by using the rake distribution near the tip towards blade back side and,for the combination of the five-bladed rotor and the seven-bladed stator,the resultant unsteady horizontal(and vertical)forces acting on the duct and stator are also reduced;while increasing rake leads to negative effect on pressure fluctuations and unsteady horizontal(and vertical)forces acting on all the components of the propulsor.

关键词： Pump-jet tip-clearance tip-rake fluctuating pressures excitation forces