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京津冀数字产业发展的时空特征及动态演化

北京社会科学 2025年第1期 15-27页

作者：叶堂林张彦淑首都经济贸易大学城市经济与公共管理学院

基于2013—2022年京津冀地区13个城市的行业数据,采用首位度指数、Zipf位序—规模法则和标准差椭圆法,从产业规模、创新能力和引资能力三个层面,对京津冀地区数字产业发展的时空特征与动态演进趋势进行了深入分析,结果显示:京津冀地区... 详细信息

基于2013—2022年京津冀地区13个城市的行业数据,采用首位度指数、Zipf位序—规模法则和标准差椭圆法,从产业规模、创新能力和引资能力三个层面,对京津冀地区数字产业发展的时空特征与动态演进趋势进行了深入分析,结果显示:京津冀地区数字产业规模差异仍然较大,但规模分布日趋合理;产业规模的空间分布呈显著扩张趋势,但其分布在径向上的不均衡性较为突出。京津冀地区数字产业创新能力不断提升,且地区间差距不断缩小;创新能力呈“先扩张,后集中,再扩张”的空间分布特征,但创新活动主要聚集在北京。京津冀地区数字产业引资能力逐年提高,但分散化的区域集聚特征逐步显现;数字经济服务业的引资能力主要聚集在北京,而数字产品制造业的引资能力则逐步向天津聚集。未来,应从共享共用数字产业创新资源平台、培强做优京津冀地区数字产业集群等方面促进京津冀数字产业发展。

关键词：数字产业标准差椭圆法位序—规模法则京津冀动态演化

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无人机集群混合合作定位高效节点筛选算法

国防科技大学学报 2025年第1期47卷 198-206页

作者：张灿李群伦伟成何永明郭冬国防科技大学系统工程学院湖南长沙410073

为解决无人机集群混合合作定位中高精度、高实时性的节点筛选问题,提出了一种高效节点筛选算法。该算法将定位方差作为评估定位精度的依据,利用减少一个节点导致定位方差变化的递推关系,筛选出指定数目的定位节点参与定位解算。与此同时... 详细信息

为解决无人机集群混合合作定位中高精度、高实时性的节点筛选问题,提出了一种高效节点筛选算法。该算法将定位方差作为评估定位精度的依据,利用减少一个节点导致定位方差变化的递推关系,筛选出指定数目的定位节点参与定位解算。与此同时,该算法增加了运算量调节因子,解决了传统节点筛选算法在较多节点数情况下计算量大、实时性差的问题。通过仿真实验,将该算法得到的方差和运算耗时与其他优化算法进行了实验对比,实验结果表明,该算法在大大减小计算量的同时保证了定位精度,具有良好的实时性和可行性。

关键词：节点筛选算法几何精度因子无人机集群合作定位

压力交变载荷作用下储气库注采管柱疲劳裂纹扩展研究

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中国安全科学学报 2025年第1期35卷 120-126页

作者：张宇张罡张强马群秦晓杰贾蕊广州大学化学化工学院广东广州510006 东北石油大学机械科学与工程学院黑龙江大庆163000

为提高注采管柱安全风险预测的准确性,首先,采用联合仿真分析方法,开展直通型缺口紧凑拉伸试样疲劳裂纹扩展过程有限元验证;然后,建立储气库含外表面裂纹注采管柱疲劳裂纹扩展有限元模型,在压力交变载荷作用下,研究储气库注采管柱的疲... 详细信息

为提高注采管柱安全风险预测的准确性,首先,采用联合仿真分析方法,开展直通型缺口紧凑拉伸试样疲劳裂纹扩展过程有限元验证;然后,建立储气库含外表面裂纹注采管柱疲劳裂纹扩展有限元模型,在压力交变载荷作用下,研究储气库注采管柱的疲劳裂纹扩展行为。研究结果表明:试样模拟结果与疲劳裂纹试验结果基本吻合,表明联合仿真法在疲劳裂纹扩展分析方面具有较高精度;在注采管柱疲劳裂纹扩展过程中,初始裂纹的长深比越大或应力比越高,裂纹扩展速率越快,临界最小裂纹长度为4 mm;在相同的压力载荷循环次数下,初始裂纹周向夹角越大,表面裂纹扩展长度越长,临界最小周向夹角为45°;无论初始裂纹周向夹角如何,裂纹始终沿管柱轴线方向扩展,裂纹失稳扩展长度为52 mm;在储气库交替注采时,应合理控制交替注采压力载荷的幅值,避免疲劳裂纹的萌生和扩展。

关键词：压力交变载荷储气库注采管柱疲劳裂纹扩展

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儿童隐匿性阴茎手术疗效评估的研究进展

中华小儿外科杂志 2025年第1期46卷 86-90页

作者：汪刚张晔张殷孙起航潮敏安徽省儿童医院泌尿外科合肥230051 上海市儿童医院泌尿外科上海200062

隐匿性阴茎是儿童常见的外生殖器疾病,其阴茎外观看似短小,但经测量,患儿耻骨联合至阴茎头的长度及阴茎体的直径正常。其致病因素主要有先天性因素及后天性因素。目前隐匿性阴茎的手术方式繁多,但由于水肿、瘢痕增生等并发症,手术疗效... 详细信息

隐匿性阴茎是儿童常见的外生殖器疾病,其阴茎外观看似短小,但经测量,患儿耻骨联合至阴茎头的长度及阴茎体的直径正常。其致病因素主要有先天性因素及后天性因素。目前隐匿性阴茎的手术方式繁多,但由于水肿、瘢痕增生等并发症,手术疗效常不能令患儿父母满意。在临床实践中即使没有发生手术并发症,一些隐匿性阴茎经手术治疗后外观也无法令人满意。近年采用小儿阴茎感知量表、尿道下裂阴茎客观评估量表、阴茎外观数据化等方法评估手术疗效的研究渐多,这些阴茎外观评估工具被证明可以较客观地综合评价手术疗效。另外,通过应用这些评估工具,一些可能与手术疗效相关的因素也被发现。本文就儿童隐匿性阴茎手术疗效的数据化评估方法及可能影响因素进行详细阐述。

关键词：阴茎疾病隐匿性阴茎疗效儿童

Advances and applications in single-cell and spatial genomics

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Science China Life Sciences 2025年

作者： Jingjing Wang Fang ye Haoxi Chai Yujia Jiang Teng Wang Xia Ran Qimin Xia Ziye Xu Yuting Fu Guodong zhang Hanyu Wu Guoji Guo Hongshan Guo Yijun Ruan Yongcheng Wang Dong Xing Xun Xu Zemin zhang Beijing Advanced Innovation Center for Genomics (ICG) Peking University Guangdong Provincial Key Laboratory of Genome Read and Write BGI Research Bone Marrow Transplantation Center of the First Affiliated Hospital & Liangzhu Laboratory Zhejiang University School of Medicine Life Sciences Institute and The Second Affiliated Hospital Zhejiang University BGI Research Biomedical Pioneering Innovation Center (BIOPIC) and School of Life Sciences Peking University Academy for Advanced Interdisciplinary Studies Peking University Institute of Hematology Zhejiang University Department of Laboratory Medicine of The First Affiliated Hospital & Liangzhu Laboratory Zhejiang University School of Medicine Center for Stem Cell and Regenerative Medicine Zhejiang University School of Medicine Zhejiang Provincial Key Lab for Tissue Engineering and Regenerative Medicine Dr.Li Dak Sum & Yip Yio Chin Center for Stem Cell and Regenerative Medicine

The applications of single-cell and spatial technologies in recent times have revolutionized the present understanding of cellular states and the cellular heterogeneity inherent in complex biological systems. These advancements offer unprecedented resolution in the examination of the functional genomics of individual cells and their spatial context within tissues. In this review, we have comprehensively discussed the historical development and recent progress in the field of single-cell and spatial genomics. We have reviewed the breakthroughs in single-cell multi-omics technologies, spatial genomics methods, and the computational strategies employed toward the analyses of singlecell atlas data. Furthermore, we have highlighted the advances made in constructing cellular atlases and their clinical applications,particularly in the context of disease. Finally, we have discussed the emerging trends, challenges, and opportunities in this rapidly evolving field.

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Polymerized-ionic-liquid-based solid polymer electrolyte for ultra-stable lithium metal batteries enabled by structural design of monomer and crosslinked 3D network

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Materials Reports: Energy 2025年第1期5卷 61-69页

作者： Liu, Lingwang Xue, Jiangyan Gao, Yiwen zhang, Shiqi zhang, Haiyang Peng, Keyang zhang, Xin Lu, Suwan Weng, Shixiao Tu, Haifeng Liu, Yang Wang, Zhicheng zhang, Fengrui Fu, Daosong Xu, Jingjing Luo, qun Wu, Xiaodong School of Nano-Tech and Nano-Bionics University of Science and Technology of China Hefei230026 China Chinese Academy of Sciences Suzhou215123 China School of Materials Science and Engineering Shanghai University Shanghai200444 China Tianmu Lake Institute of Advanced Energy Storage Technologies Liyang213300 China Institute of Physics Chinese Academy of Sciences Beijing100190 China College of Material Science and Engineering Hohai University Changzhou213022 China

Solid polymer electrolytes (SPEs) have attracted much attention for their safety, ease of packaging, cost-effectiveness, excellent flexibility and stability. Poly-dioxolane (PDOL) is one of the most promising matrix materials of SPEs due to its remarkable compatibility with lithium metal anodes (LMAs) and suitability for in-situ polymerization. However, poor thermal stability, insufficient ionic conductivity and narrow electrochemical stability window (ESW) hinder its further application in lithium metal batteries (LMBs). To ameliorate these problems, we have successfully synthesized a polymerized-ionic-liquid (PIL) monomer named DIMTFSI by modifying DOL with imidazolium cation coupled with TFSI− anion, which simultaneously inherits the lipophilicity of DOL, high ionic conductivity of imidazole, and excellent stability of PILs. Then the tridentate crosslinker trimethylolpropane tris[3-(2-methyl-1-aziridine)propionate] (TTMAP) was introduced to regulate the excessive Li+-O coordination and prepare a flame-retardant SPE (DT-SPE) with prominent thermal stability, wide ESW, high ionic conductivity and abundant Li+ transference numbers (tLi+). As a result, the LiFePO4|DT-SPE|Li cell exhibits a high initial discharge specific capacity of 149.60 mAh g−1 at 0.2C and 30 °C with a capacity retention rate of 98.68% after 500 cycles. This work provides new insights into the structural design of PIL-based electrolytes for long-cycling LMBs with high safety and stability. © 2024 The Authors

关键词： Crosslinking

金融结构与企业发展韧性：影响效应及作用机制

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学习与实践 2025年第2期 64-75+2页

作者：胡海峰张烨北京师范大学经济与工商管理学院金融系中国国际金融学会世界经济学会中华外国经济学说研究会北京区域经济学会北京师范大学经济与工商管理学院

优化金融结构，提高资源配置效率，对推动企业高质量发展具有重要意义。基于2013-2022年我国沪深A股上市公司的研究发现，相比银行主导型金融结构，市场主导型金融结构更有助于企业发展韧性的提升；金融结构市场化主要通过增强资源获取... 详细信息

优化金融结构，提高资源配置效率，对推动企业高质量发展具有重要意义。基于2013-2022年我国沪深A股上市公司的研究发现，相比银行主导型金融结构，市场主导型金融结构更有助于企业发展韧性的提升；金融结构市场化主要通过增强资源获取能力、提高风险承担水平和改善协同治理状况促进企业韧性发展；对外融资依赖程度越高、管理层持股比例越高的企业，市场型金融结构对其发展韧性的积极影响更为显著；当金融发展水平超过一定门槛值时，金融结构市场化的积极作用才逐渐显露。此外，数字金融在金融结构与企业韧性的关系中发挥着正向调节作用。因此，健全中国特色多层次资本市场体系，加快全面实施注册制改革，积极发展债券市场、风险投资等直接融资渠道，加强银行间竞争，以促进金融结构向市场化转型，进而提升企业发展韧性。

关键词：金融结构企业发展韧性金融发展水平数字金融

High-precision magnetic field measurement system based on a coherent population trapping magnetometer onboard the SATech-01 satellite

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Science China(Technological Sciences) 2025年第2期68卷 227-242页

作者： Hongbo XUE Wei SONG Haoran ZHAO Yiteng zhang Shanzhi ye Jindong WANG Ran TAO Peng SANG Keli CHEN Xingzi BI Bingjun CHENG Bin ZHOU Yongliang XUE Yingying TANG Liu LIU Jinsong LI Xiaocheng ZHU Baoquan LI Jinguo LIU Wen CHEN Xiaofeng zhang Yonghe zhang Lei LI State Key Laboratory of Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China Key Laboratory of Solar Activity and Space Weather National Space Science CenterChinese Academy of SciencesBeijing 100190China Key Laboratory of Electronics and Information Technology for Space Systems National Space Science CenterChinese Academy of SciencesBeijing 100190China State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang 110016China Innovation Academy for Microsatellites Chinese Academy of SciencesShanghai 201304China

On July 27,2022,a high-precision system for measuring the magnetic field based on a coherent population trapping magnetometer(referred to as the CPT system)was launched onboard the Space Advanced Technology demonstration satellite(SATech-01)by a ZK-1A *** payload comprises a scalar coherent population trapping magnetometer(CPTM),triaxial anisotropic magnetoresistance magnetometer(AMRM),and nano star tracker mounted on a non-magnetic telescopic tubular *** configuration enables synchronized measurement of scalar and vector geomagnetic fields,as well as the attitude,making the payload with its compact sensors suitable for applications on miniature satellite *** November 7,2022,the novel telescopic tubular mast was deployed in orbit,extending to a length of 5.28 *** CPTM,an absolute scalar magnetometer with an omnidirectional sensor,is the first China-developed quantum/atomic magnetometer successfully operating in *** orbit,the CPTM has sensitivity of~10 pT/Hz^(1/2) and can automatically operate under complex magnetic field *** difference between the scalar fields obtained using the CPTM and CHAOS model has a mean deviation of -3.73 nT and a standard deviation of 26.11 nT(1σ),without on-orbit calibration or *** miniaturized AMRM has a sensitivity of~0.3 nT/Hz^(1/2) and maintains stable and reliable operation in *** low-power and miniaturized nano star tracker has a measurement uncertainty of 14.23″(1σ)in *** mission has realized the on-orbit technical verification of the integrated and synchronized detection of the vector magnetic field and attitude and fully validated the system’s performance,automation level,and reliability.

关键词： magnetic field measurement system coherent population trapping magnetometer anisotropic magnetoresistance magnetometer nano star tracker non-magnetic telescopic tubular mast satellite

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Effect of heat treatment on microstructure and mechanical properties of a novel Al-Zn-Mg-Cu alloy

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China Foundry 2025年

作者： Yan-mei Yang Xin-chen Tang ye-fei Li Xue-wei Fang Da-wei Yi Zhi-yun zhang Qiao-ling Zheng Zhi-xi Wang Guo-yu zhang Su zhang Hao Cheng Yang He Yi-bo Liu Zi-han Wu Ya-nan Chen Yi-min Gao State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong University Xi'an Aerospace Precision Electromechanical Institute

Effects of solution and aging treatment on the microstructure and mechanical properties of a novel Al-Zn-Mg-Cu alloy by microalloying rare elements Sc and Er were studied. The results show that solution time has a visible influence on the microstructure and mechanical properties of the alloy. Specifically, as the solution time increases, the area fraction of the residual phase in the alloy decreases, and the shape of the grain becomes more spheroidal and coarser, leading to a decrease in hardness. This is attributed to the dissolution of strengthening phases during the solution treatment, which weakens the solid solution strengthening *** single-stage aging treatment shows an initial increase in strength and hardness of the alloy, followed by a decrease as the aging time is extended, until a steady state is achieved. The optimal single-aging conditions are found to be at 120 ℃ for 24 h, where the alloy exhibits an excellent combination of high strength and good ductility, with an ultimate tensile strength(UTS) of 523 MPa, yield strength(YS) of 482 MPa, and elongation(El)of 1.75%, respectively. Compared to single-stage aging, double-stage aging(120 ℃ for 24 h and then 150 ℃ for 52 h) significantly increases the elongation of the alloy(4.17%), but the UTS reduces to 465.29 MPa, and YS reduces to 410.64 MPa. Transmission electron microscopy(TEM) observations disclose that the grain size, the distribution spacing of precipitates along the grain boundary, and the width of the precipitation-free zone(PFZ) all undergo augmentation as the duration of the second stage aging process elongates.

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