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Recent advances in electrocatalysts for non-aqueous Li-O2 batteries

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Chinese Chemical Letters 2017年第4期28卷 709-718页

作者： wei Chen Ya-Feng gong jie-Hua Liu Future Energy Laboratory School of Materials Science and Engineering Hefei University of Technology Hefei 230009 China

As one of the next-generation energy-storage devices,Li-O_2 battery has become the main research direction for the academic researchers due to its characteristics of environmental friendship,relatively simple structures,high energy density of 3500Wh/kg and low ***,Li-O_2 battery cannot be commercialized on a large scale because of the challenging issues including high-efficient electrocatalysts,membranes,Li-based anode and so *** this review,we focused on the recent development of electrocatalyst materials as cathodes for the non-aqueous Li-O_2 batteries which are relatively simpler than other Li-O_2 batteries＇ *** were summarized including noble metals,nanocarbon materials,transition metals and their *** points out that the challenges of preparation high-efficient catalysts not only require high catalytic activity and conductivity,but also have novel nanoarchitectures with large interface and porous volume for LiO_x ***,the further investigation of reaction mechanism and advanced in situ analysis technologies are welcome in the coming work.

关键词： Electric vehicle Li-O2 battery High capacity Catalysts Electrocatalysis

Successful management of bleeding ectopic small bowel varices secondary to portal hypertension:A retrospective study

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World Journal of Gastrointestinal Surgery 2025年第3期17卷 300-306页

作者： Nian-Jun Xiao Jian-Guo Chu Shou-Bin Ning Bao-jie wei Zhi-Bo Xia Zhe-Yi Han Department of Gastroenterology Air Force Medical CenterAir Force Medical UniversityBeijing 100142China

BACKGROUND Bleeding ectopic varices located in the small bowel(BEV-SB)caused by portal hypertension(PH)are rare and life-threatening clinical *** current management of BEV-SB is *** retrospective study analyzed four cases of BEV-SB caused by PH and detailed the management of these cases using enteroscopic injection sclerotherapy(EIS)and subsequent interventional radiology(IR).AIM To analyze the management of BEV-SB caused by PH and develop a treatment *** This was a single tertiary care center before-after study,including four patients diagnosed with BEV-SB secondary to PH between January 2019 and December 2023 in the Air Force Medical Center.A retrospective review of the medical records was *** management of these four patients involved the utilization of EIS followed by *** management duration of BEV-SB in each patient can be retrospectively divided into three phases based on these two approaches:Phase 1,from the initial occurrence of BEV-SB to the initial EIS;phase 2,from the initial EIS to the initial IR treatment;and phase 3,from the initial IR to December *** statistics were performed to clarify the blood transfusions in each *** Four out of 519 patients diagnosed with PH were identified as having *** management duration of each phase was 20 person-months,42 personmonths,and 77 person-months,*** four patients received a total of eight and five person-times of EIS and IR treatment,*** patients exhibited recurrent gastrointestinal bleeding following the first EIS,while no further instances of gastrointestinal bleeding were observed after IR *** transfusions administered during each phase were 34,31,and 3.5 units of red blood cells,and 13 units,14 units,and 1 unit of plasma,*** EIS may be effective in achieving hemostasis for BEV-SB,but rebleeding is common,and IR aiming to reduce portal pressure gradient may lower the rebleed

关键词： Suspected small bowel bleeding Transjugular intrahepatic portosystemic shunt Enteroscopic injection sclerotherapy Bleeding ectopic varices Portal hypertension

Beam performance of the SHINE dechirper

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Nuclear Science and Techniques 2021年第3期32卷 72-81页

作者： You-wei gong Meng Zhang wei-jie Fan Duan Gu Ming-Hua Zhao Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China

A corrugated structure is built and tested on many FEL facilities,providing a'dechirper'mechanism for eliminating energy spread upstream of the undulator section of X-ray *** wakefield effects are here studied for the beam dechirper at the Shanghai high repetition rate XFEL and extreme light facility(SHINE),and compared with analytical *** properly optimized,the energy spread is well *** transverse wakefield effects are also studied,including the dipole and quadrupole *** using two orthogonal dechirpers,we confirm the feasibility of restraining the emittance growth caused by the quadrupole wakefield.A more efficient method is thus proposed involving another pair of orthogonal dechirpers.

关键词： Corrugated structure Energy spread Wakefield Shanghai high repetition rate XFEL and extreme light facility

AeroMTP:A fountain code-based multipath transport protocol for airborne networks

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Chinese Journal of Aeronautics 2015年第4期28卷 1147-1162页

作者： Li jie gong Erling Sun Zhiqiang Liu wei Xie Hongwei College of Mechatronic Engineering and Automation National University of Defense Technology

Airborne networks（ANs） are special types of ad hoc networks that can be used to enhance situational awareness, flight coordination and flight efficiency in civil and military *** to ground networks, ANs have some unique attributes including high node mobility, frequent topology changes, mechanical and aerodynamic constrains, strict safety requirements and harsh communication ***, the performance of conventional transmission control protocol（TCP） will be dramatically degraded in *** commonly have two or more heterogeneous network interfaces which offer an opportunity to form multiple communication paths between any two nodes in *** satisfy the communication requirements in ANs, we propose aeronautical multipath transport protocol（Aero MTP） for ANs, which effectively utilizes the available bandwidth and diversity provided by heterogeneous wireless *** MTP uses fountain codes as forward error correction（FEC） codes to recover from data loss and deploys a TCP-friendly rate-based congestion control mechanism for each ***, we design a packet allocation algorithm based on optimization to minimize the delivery time of *** performance of Aero MTP is evaluated through OMNe T＋＋ simulations under a variety of test *** demonstrate that Aero MTP is of great potential to be applied to ANs.

关键词： Ad hoc networks Airborne networks Fountain code Multi-paths Network protocols

Medium–Extended Range Forecasting of Meiyu in 2023: Performance of CMA and ECMWF GEPSs

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Journal of Meteorological Research 2025年第1期 193-210页

作者： Ruoyun NIU Baiquan ZHOU wei HUANG Yu gong Couhua LIU National Meteorological Centre China Meteorological Administration Chinese Academy of Meteorological Sciences China Meteorological Administration Earth System Modeling and Prediction Centre China Meteorological Administration

Meiyu, featuring prolonged periods of rainfall over the Yangtze–Huai River basin(YHRB), not only replenishes water resources and sustains ecological balance, but also poses potential disaster risks. Accurate early forecasting of Meiyu is crucial for effectively implementing flood prevention strategies. To help refine numerical models and providing guidance for operational forecasters, this study explores the capabilities of two global ensemble prediction systems(GEPSs) of the China Meteorological Administration(CMA) and the ECMWF in forecasting the Meiyu characteristics in 2023 over the YHRB. Results show that the ECMWF GEPS reasonably forecasts the Meiyu rainfall, while the CMA GEPS presents a notable underestimation. The predictable lead time of the Meiyu onset date is eight days by the ECMWF GEPS and six days by the CMA GEPS, respectively. Regarding the regional rainstorm processes, the two GEPSs generally provide a predictable lead time of 48–168 h for reasonably forecasting the patterns of the heavy rainfall area. To further examine their strengths and weaknesses in Meiyu forecasting, this paper revisits their abilities in forecasting key influence systems. By verifying against their respective analyses, it is demonstrated that the ECMWF GEPS reasonably forecasts the spatial coverages of the northwestern Pacific subtropical high(NWPSH) and the South Asian high(SAH), whereas the CMA GEPS presents substantial underestimation. Both GEPSs show generally southward deviations for the eastern ridge line position(RLP) of the SAH, and exhibit a northward deviation for the western RLP of the NWPSH during early forecast lead times. The less Meiyu rainfall predicted by the CMA GEPS compared to the ECMWF GEPS can be attributed to its weaker low-level convergence belt and weaker upper-level divergence area. A deeper exploration into these forecast discrepancies in upper-level divergence and lower-level convergence suggests that they likely originate from their initial analys

关键词：

沃柑可溶性固形物含量高光谱检测模型的建立与优化

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光谱学与光谱分析 2025年第2期45卷 492-500页

作者：李炜琪王一帆俞越刘洁华中农业大学工学院湖北武汉430070 农业农村部长江中下游农业装备重点实验室湖北武汉430070 农业农村部柑橘全程机械化科研基地湖北武汉430070

针对沃柑品质快速检测需求,提出一种基于高光谱图像数据的沃柑可溶性固形物含量(SSC)检测方法,并分析随贮藏时间变化的SSC伪彩色分布图。分别获取307个整果样本和227个半果样本以及它们的SSC数据。比较标准正态变换(SNV)、多元散射校正(... 详细信息

针对沃柑品质快速检测需求,提出一种基于高光谱图像数据的沃柑可溶性固形物含量(SSC)检测方法,并分析随贮藏时间变化的SSC伪彩色分布图。分别获取307个整果样本和227个半果样本以及它们的SSC数据。比较标准正态变换(SNV)、多元散射校正(MSC)、Savitzky-Golay(SG)滤波、归一化(NM)、一阶导数(FD)、标准化(SD)和小波变换(WT)对偏最小二乘回归(PLSR)模型检测性能的影响以选择光谱预处理方法;比较PLSR、最小绝对值收缩与选择算子(LASSO)回归、支持向量机回归(SVR)、人工神经网络(ANN)、决策树(DT)、随机森林(RF)、轻量级梯度提升机(LightGBM)模型对独立验证集的检测能力以确定最佳模型建立方法,并利用遗传算法(GA)筛选特征波长以优化模型。结果表明:采用FD预处理结合LASSO回归算法所建模型对整果SSC检测效果最优,验证集决定系数(R_(p)^(2))和验证集均方根误差(RMSEP)分别为0.9257和0.9765;SD预处理结合RF模型对半果SSC检测效果最好,其R_(p)^(2)和RMSEP分别为0.8963和1.0630;GA能够滤除53.85%和50.58%的整果和半果波长变量数,基于选择变量的整果和半果最优建模算法分别为SVR和RF,其模型R_(p)^(2)、RMSEP分别为0.9189、1.0173和0.8953、1.0843。研究结果为沃柑SSC高通量无损检测提供了一种可行方案。

关键词：沃柑高光谱可溶性固形物含量无损检测集成学习

共建“一带一路”倡议与服务贸易合作——基于服务贸易网络视角

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管理世界 2025年第1期41卷 1-14,50页

作者：吕炜王杰王伟同东北财经大学经济学院东北财经大学东北全面振兴研究院

共建“一带一路”倡议作为构建人类命运共同体的重大实践,在构建共生共荣的新型国际关系过程中发挥了重要作用。本文聚焦服务贸易这一兼具人文交流和市场发展双重特征的国际交往方式,基于服务贸易网络视角,构建2006~2019年国家层面的面... 详细信息

共建“一带一路”倡议作为构建人类命运共同体的重大实践,在构建共生共荣的新型国际关系过程中发挥了重要作用。本文聚焦服务贸易这一兼具人文交流和市场发展双重特征的国际交往方式,基于服务贸易网络视角,构建2006~2019年国家层面的面板数据,并利用双重差分方法研究共建“一带一路”倡议对共建国家间服务贸易合作的影响。研究结果显示,共建“一带一路”倡议显著提高了共建国家之间的服务贸易合作。研究机制分析发现,共建“一带一路”倡议提出后共建国家间的制度环境、人文环境、通信环境、运输环境以及融资环境明显改善,使得共建国家间服务贸易合作愈加紧密。进一步分析表明,该倡议对于沿海国家、海上丝绸之路国家和低收入、低风险国家的服务贸易合作具有显著正向影响;按照服务贸易类型和服务贸易基础进行划分,这一倡议有助于增加共建国家间新兴服务贸易和传统服务业的服务贸易合作,发挥了“搭桥建路”的作用。本文为高质量共建“一带一路”提供了理论支撑,力图为全球治理中的国际合作实践提供更多共建启示。

关键词：共建“一带一路”倡议服务贸易合作服务贸易网络

数字经济赋能养老服务业跨越“低水平均衡陷阱”

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河北学刊 2025年第1期45卷 152-161页

作者：夏杰长罗敬蔚中国社会科学院财经战略研究院中央财经大学法学院

中国养老服务业正面临低水平需求与高成本供给之间的矛盾,这直接导致养老服务业陷入“低水平均衡陷阱”。数字经济在优化养老资源配置、降低养老服务成本和完善养老生态系统等方面发挥了重要作用,是跨越养老服务业“低水平均衡陷阱”的... 详细信息

中国养老服务业正面临低水平需求与高成本供给之间的矛盾,这直接导致养老服务业陷入“低水平均衡陷阱”。数字经济在优化养老资源配置、降低养老服务成本和完善养老生态系统等方面发挥了重要作用,是跨越养老服务业“低水平均衡陷阱”的重要力量。借力数字经济推动养老服务实现高水平均衡,进而实现养老服务业高质量发展,需要综合施策:适当延长老年群体工作年限;对老年人口进行数字技术培训,助力他们跨越数字鸿沟;利用数字技术优化养老服务的资源配置;多渠道降低养老服务业成本;提升从业人员数字素养。

关键词： “低水平均衡陷阱” 老龄化数字经济养老服务业

Cross-stacking crystal structural configuration of integrated cathode materials for proton-conducting solid oxide fuel cells

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Rare Metals 2024年第11期43卷 6088-6095页

作者： Jun-Yi gong Dan-Dan Yang wei Liu jie Hou School of Resource Environment and Safety Engineering University of South ChinaHengyang 421001China CAS Key Laboratory of Materials for Energy Conversion and Collaborative Innovation Center of Suzhou Nano Science and Technology University of Science and Technology of ChinaHefei 230026China

The absence of cathode materials with excellent activity and stability has hampered the widespread application of proton-conducting solid oxide fuel cells(H-SOFCs).Sm_(2)Ba_(1.33)Ce_(0.67)Cu_(3)O_(9)(SBCC)is a layered material formed by the cross-stacking of a[CuO_(5)layer][CeO_(2)-like layer][CuO_(5)layer][Sm_(x)Ba_(1-x)CuO_(y)perovskite layer].This complex structure could potentially enhance electrocatalytic performance owing to the integration of differentstructural,chemical and electronic properties.

关键词： structural stacking solid