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Spatial-temporal distribution and emission of urban scale air pollutants in Hefei based on Mobile-DOAS

Journal of Environmental Sciences 2025年第5期151卷 238-251页

作者： Zhidong Zhang Pinhua Xie Ang Li Min Qin jin xu Zhaokun Hu Xin Tian Feng Hu Yinsheng Lv Jiangyi Zheng Youtao Li School of Environmental Science and Optoelectronic Technology University of Science and Technology of ChinaHefei 230026China Key Laboratory of Environmental Optics and Technology Anhui Institute of Optics and Fine MechanicsHefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China University of Chinese Academy of Sciences Beijing 100049China Information Materials and Intelligent Sensing Laboratory of Anhui Province Institutes of Physical Science and Information TechnologyAnhui UniversityHefei 230601China

As a significant city in the Yangtze River Delta regions,Hefei has experienced rapid changes in the sources of air pollution due to its high-speed economic development and urban ***,there has been limited research in recent years on the spatial-temporal distribution and emission of its atmospheric *** address this,this study conducted mobile observations of urban roads using the Mobile-DOAS instrument from June 2021 to May *** monitoring results exhibit a favourable consistent with TROPOMI satellite data and ground monitoring station ***,there were pronounced seasonal variations in air ***,high concentration of HCHO and NO_(2)were closely associated with traffic congestion on roadways,while heightened SO_(2)levels were attributed to winter heating and industrial *** study also revealed that with the implementation of road policies,the average vehicle speed increased by 95.4%,while the NO concentration decreased by 54.4%.In the estimation of urban NO_(x)emission flux,it was observed that in temporal terms,compared with inventory data,the emissions calculated viamobile measurements exhibitedmore distinct seasonal patterns,with the highest emission rate of 349 g/sec in winter and the lowest of 142 g/sec in *** spatial terms,the significant difference in emissions between the inner and outer ring roads also suggests the presence of the city’s primary NO_(x)emission sources in the area between these two *** study offers data support for formulating the next phase of air pollution control measures in urban areas.

关键词： Mobile-DOAS HCHO NO_(2) SO_(2) Spatial-temporal distribution NOx emission

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Stable geometries and magnetic properties in transition-metaldoped Sm5Co19 permanent magnet alloys:Insights from DFT

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Science China(Physics,Mechanics & Astronomy) 2025年

作者： Cheng Fang Zhi Yan xu-jin Zhang Jian-Hua Xiao Fang Wang Xiao-Hong xu School of Chemistry and Materials Science of Shanxi Normal University&Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education Research Institute of Materials Science Shanxi Key Laboratory of Advanced Magnetic Materials and DevicesShanxi Normal University

Sm5Co19permanent magnet alloy holds significant potential for applications due to its ultra-high intrinsic coercivity,low temperature coefficient of coercivity and high Curie ***,its metastable nature poses challenges for experimental *** we propose to use transition metal doping to effectively improve the structural stability and comprehensive magnetic properties of Sm5Co19based on first-principles *** find that Sc,Ti,V,Cr,Mn,and Zr preferentially occupy the Sm-6c2 site,while Fe,Ni,Cu,and Zn preferentially occupy the Co-6c2,Co-18h1,Co-18h2,and Co-18h2 site,***,doping elements at their optimal sites significantly enhance the structural stability of the doped *** substituting Sm or Co sites,doping with Cr,Mn,and Fe significantly increases the total magnetic moment of the *** the number of doping atoms range from 0 to 12,doping with Cr,Mn,and Fe enhances both the structural stability and the total magnetic moment of the Sm5Co19system,further confirming the significant impact of atomic site occupation on the performance of the doped *** study presents a feasible approach for enhancing the structural stability of Sm5Co19permanent magnets and offers valuable theoretical guidance for the development of highperformance Sm-Co based permanent magnet materials.

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体制、交际与猜疑:论1933—1935年华北对日交涉

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安徽史学 2025年第1期 73-82页

作者：徐进山东大学历史学院山东济南250100

长城抗战结束后,国民政府构建了以政整会和军分会为主体的地方交涉体制,其运行为中央对日交涉创造了回旋余地。但在日方多头交涉的重压下,两会体制举步维艰,最终黯然退场,华北交涉之责收归中央。黄郛等人一度借助私人交际缓和中日关系,... 详细信息

长城抗战结束后,国民政府构建了以政整会和军分会为主体的地方交涉体制,其运行为中央对日交涉创造了回旋余地。但在日方多头交涉的重压下,两会体制举步维艰,最终黯然退场,华北交涉之责收归中央。黄郛等人一度借助私人交际缓和中日关系,但多方交涉之弊亦迅速显现。且私人交际清晰地反映出中日权势强弱关系,地位的不对等反为日方索求打开了便利之门。这一时期的中日交涉始终在高度猜嫌的氛围下进行,信任危机加剧了双方的立场分歧,而激进化手段的采取又反过来助长了猜嫌心理,中日关系在恶性循环中滑向谷底。然而,全面抗战爆发前的日本侵华活动具有清晰的连贯性,日方对中方“诚意”的无理诉求基于一种荒谬的认知逻辑。

关键词：中日交涉华北事变两会体制交际猜疑

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Recent progress on photoactive nonprecious transition-metal complexes

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Science China Chemistry 2025年第1期68卷 46-95页

作者： Zhong-Liang Gong Hong-Jie Zhang Yan Cheng Jianxun Liu Yuhan Ai Yaqin Li Zhihui Feng Qiong Zhang Shaolong Gong Yong Chen Chang-Jiang Yao Yuan-Yuan Zhu Liang-jin xu Yu-Wu Zhong CAS Key Laboratory of Photochemistry Institute of ChemistryChinese Academy of SciencesBeijing 100190China State Key Laboratory of Structural Cemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China School of Chemistry and Chemical Engineering Anhui Key Laboratory of Advanced Catalytic Materials and Reaction EngineeringHefei University of TechnologyHefei 230009China State Key Laboratory of Explosion Science and Safety Protection School of Mechatronical EngineeringBeijing Institute of TechnologyBeijing 100081China College of Chemistry and Molecular Sciences Hubei Key Lab on Organic and Polymeric Optoelectronic MaterialsWuhan UniversityWuhan 430072China School of Chemistry and Chemical Engineering Anhui UniversityHefei 230601China Key Laboratory of Photochemical Conversion and Optoelectronic Materials&CAS-HKU Joint Laboratory on New Materials Technical Institute of Physics and ChemistryChinese Academy of SciencesBeijing 100190China

Photoactive complexes of nonprecious transition metals,mainly including those in the first-row and partially the second-row of the Periodic table of elements,have received increasing attention in view of their low cost and long-term *** are recognized as promising alternatives to noble transition metal complex congeners that have been extensively studied in optoelectronic devices,artificial photosynthesis,photocatalysis,biodiagnostics,and therapeutics,*** review is devoted to a comprehensive summary on the classical and recent advances on photoactive nonprecious transition metal complexes,including photoactive Zr,V,Cr,Mo,and W complexes,Mn complexes and hybrids,Fe,Co,Ni,and Cu complexes,and Zn and Cd complexes and hybrids.A particular focus is given on the molecular design,modulation of photophysical and photochemical properties,and applications of the representative and lately-developed nonprecious metal *** addition,a perspective on the future development in this field is provided at the end of this review.

关键词： photoactive metal complexes earth-abundant metals nonprecious metal complexes luminescence photochemistry

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新时代以来中国共产党领导对外工作的主要方法探析

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俄罗斯东欧中亚研究 2025年第1期 1-16+159页

作者：徐进中国社会科学院大学国际政治经济学院中国社会科学院世界经济与政治研究所习近平外交思想研究室

坚持以维护党中央权威为统领加强党对对外工作的集中统一领导是习近平外交思想“十个坚持”的第一条，是中国对外工作的根本政治属性的体现。坚持加强党对对外工作的集中统一领导，是坚持党对一切工作的领导的重要方面，是做好对外工作... 详细信息

坚持以维护党中央权威为统领加强党对对外工作的集中统一领导是习近平外交思想“十个坚持”的第一条，是中国对外工作的根本政治属性的体现。坚持加强党对对外工作的集中统一领导，是坚持党对一切工作的领导的重要方面，是做好对外工作的根本保证。党对对外工作的集中统一领导是中国外交的最大特色和最大优势。在中国外交的每一个关键节点，党的领导都为中国外交的成功推进提供了政治引领，当前的元首外交是最能体现党对外交工作政治引领作用的形式。对外工作体制机制改革是推进国家治理体系和治理能力现代化的内在要求。党的十八大以来，在以习近平同志为核心的党中央统一领导和部署下，对外工作体制机制改革取得显著成就。在此基础上，党中央可以更加有效地统筹协调对外工作的各个参与主体，形成对外工作大协同的局面。与此同时，对外工作的法律体系和人才体系不断完善，有效保障了对外工作的顺利前行。在新时期中，只有把“党管外事、党办外交”的优良传统发扬光大，才能在错综复杂的国际形势中保持定力、把握主动。

关键词：习近平外交思想对外工作外交政策元首外交外交决策机制涉外法治

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抽水蓄能电站同发同抽运行下竖井式进/出水口的水力特性研究

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水电能源科学 2025年第2期43卷 181-185页

作者：徐振鹏陈青生徐津河海大学水利水电学院江苏南京210098

抽水蓄能电站具有灵活的运行方式,有时需采用不同水力单元机组同时处于发电和抽水的运行方式,以改善电网的供电质量。为研究同发同抽运行时竖井式进/出水口的水力特性,基于某抽水蓄能电站上水库竖井式进/出水口的体型及设计参数,采用水... 详细信息

抽水蓄能电站具有灵活的运行方式,有时需采用不同水力单元机组同时处于发电和抽水的运行方式,以改善电网的供电质量。为研究同发同抽运行时竖井式进/出水口的水力特性,基于某抽水蓄能电站上水库竖井式进/出水口的体型及设计参数,采用水动力模型方法,开展了两水力单元在同发同抽运行工况下的数值仿真计算,对孔道流量分布、流速分布及其不均匀性以及进、出流水力单元的间距进行了分析。结果表明,同发同抽运行工况下两水力单元间水流的“短路”流动将加剧进流水力单元孔道流量分布的不均匀性,对出流水力单元的流量分布、孔道流速分布基本不产生影响;同发同抽运行工况下两水力单元间的相对间距大于13.1时,进流水力单元的这种流量不均性将会得到解决。

关键词：抽水蓄能电站同发同抽竖井式进/出水口水力特性数值模拟

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用于脑肿瘤分割的N形神经网络

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小型微型计算机系统 2025年第2期46卷 365-372页

作者：迟孟贤安虹金旭许延杰聂振国中国科学技术大学计算机科学与技术学院合肥230027 清华大学机械工程系北京100084

传统的U型神经网络网络在脑肿瘤分割任务中存在高层信息表征能力不足和分割标签不平衡等问题.本文提出了一种新型脑肿瘤分割模型N-Net,能够有效融合多尺度信息,综合考虑全局语义与局部细节,提高了对不同大小肿瘤的分割性能.模型引入特... 详细信息

传统的U型神经网络网络在脑肿瘤分割任务中存在高层信息表征能力不足和分割标签不平衡等问题.本文提出了一种新型脑肿瘤分割模型N-Net,能够有效融合多尺度信息,综合考虑全局语义与局部细节,提高了对不同大小肿瘤的分割性能.模型引入特征金字塔进行多尺度语义特征的传递,并且采用通道空间融合注意力机制自适应地关注与肿瘤相关区域,此外,本文增加了模型层级并利用残差卷积模块解决梯度消失问题.最后,本文采用改进的混合损失函数应对标签不平衡问题,提高了分割结果的准确性和鲁棒性.在MSD数据集上的实验结果表明,本文提出的方法在多个评估指标上显著优于其他先进模型,展示了其在脑肿瘤分割任务上的有效性.

关键词：脑肿瘤分割特征金字塔注意力机制混合损失函数 N形神经网络

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Realization of edge states along a synthetic orbital angular momentum dimension

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Photonics Research 2025年第01期13卷 87-97页

作者： YU-WEI LIAO MU YANG HAO-QING ZHANG ZHI-HE HAO JUN HU TIAN-XIANG ZHU ZONG-QUAN ZHOU XI-WANG LUO jin-SHI xu CHUAN-FENG LI GUANG-CAN GUO CAS Key Laboratory of Quantum Information University of Science and Technology of China Anhui Province Key Laboratory of Quantum Network University of Science and Technology of China CAS Center for Excellence in Quantum Information and Quantum Physics University of Science and Technology of China Hefei National Laboratory University of Science and Technology of China

Synthetic dimensions have emerged as promising methodologies for studying topological physics, offering great advantages in controllability and flexibility. Photonic orbital angular momentum(OAM), characterized by discrete yet unbounded properties, serves as a potent carrier for constructing synthetic dimensions. Despite the widespread utilization of synthetic OAM dimensions in the investigation of topological physics, the demonstration of an edge along such dimensions has remained challenging, significantly constraining the exploration of important topological edge effects. In this study, we establish an edge within a Floquet Su–Schrieffer–Heeger OAM lattice, creating approximate semi-infinite lattices by introducing a pinhole in the optical elements within a cavity. Leveraging the spectral detection capabilities of the cavity, we directly measure the phase transitions of zero(±π) energy edge states, elucidating the principle of bulk-edge correspondence. Furthermore, we dynamically observe the migration of edge modes from the gap to the bulk by varying the edge phase, and we reveal that interference near the surface results in the discretization of the spectrum. We offer, to our knowledge,a novel perspective for investigating edge effects and provide an important photonic toolbox in topological photonics.

关键词： Beam splitters Information processing Optical elements Orbital angular momentum multiplexing Photonics Quantum information

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[Analgesic effect of "Zhibian" (BL54)-toward-"Shuidao" (ST28) needling technique of acupuncture on primary dysmenorrhea based on NOD1/RIP2/NF-κB signaling pathway in the rats]

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Zhongguo zhen jiu = Chinese acupuncture & moxibustion 2025年第2期45卷 209-16页

作者： xu jin Yanlin Zhang Boya Chang Jia Ren Jianheng Hao Yuxia Cao Haijun Wang Laixi Ji Second Clinical College Shanxi University of CM Jinzhong 030619 China. School of Acupuncture-Moxibustion and Tuina Tianjin University of TCM. Affiliated Hospital of Acupuncture-Moxibustion and Tuina Shanxi University of CM Taiyuan 030012.

OBJECTIVE:To observe the effect of "Zhibian" (BL54)-toward-"Shuidao" (ST28) needling technique on the relative protein expression of the signaling pathway of nucleotide-binding oligomerization domain-containing protein 1 (NOD1)/ receptor-interacting protein 2 (RIP2)/nuclear factor kappa-B (NF-κB) and the expression of proinflammatory cytokines in the rats with primary dysmenorrhea (PD), so as to explore the underlying mechanism of this acupuncture technique for pain alleviation in PD.METHODS:Thirty female SD rats of SPF grade with normal estrous cycle were randomized into a blank group, a model group and an acupuncture group, 10 rats in each one. Using the intraperitoneal injection with estradiol benzoate combined with oxytocin, PD model was prepared in the model group and the acupuncture group. In the acupuncture group, during model preparation, the intervention with "Zhibian" (BL54)-toward-"Shuidao" (ST28) needling technique was delivered simultaneously, 20 min each time, once daily for consecutive 10 days. On day 11, within 30 min after the intraperitoneal injection with oxytocin, the writhing reaction (latency, frequency and score) was recorded; the morphology of uterine tissue was observed with HE staining, the contents of prostaglandin E (PGE), prostaglandin F (PGF), interleukin (IL)-1β, IL-18, cyclooxygenase-2 (COX-2), and tumor necrosis factor-α(TNF-α) in the serum were detected using ELISA method; the relative protein expression of NOD1, RIP2, NF-κB p65, phosphorylation-NF-κB p65 (p-NF-κB p65) was detected in the uterine tissue using Western blot method; and the mRNA expression of NOD1, RIP2 and NF-κB p65 was detected with the quantitative real-time PCR employed.RESULTS:Compared with the blank group, in the model group, the writhing latency was prolonged (<0.01), the writhing frequency and score increased (<0.01) in the rats; the endometrial epithelial cells showed massive degeneration and necrosis, with severe endometrial edema and widespread shedding, c

关键词： NOD1/RIP2/NF-κB signaling pathway Zhibian (BL54)-toward-Shuidao (ST28) acupuncture inflammatory response pain primary dysmenorrhea

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小箱梁加宽桥在高速公路改扩建中的应用和受力性能研究

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公路 2025年第1期70卷 282-286页

作者：吴斌峰徐金华中交第一公路勘察设计研究院有限公司西安市710075 山西省交通规划勘察设计院有限公司太原市030032

近年来,小箱梁加宽桥在高速公路改扩建中得到广泛应用,而新旧桥梁的拼接方式是桥梁加宽的关键。以山西昔榆高速拼宽桥为工程背景,利用数值模拟方法,首先论述了减少不均匀沉降的应对措施;其次对不同湿接缝拼接宽度下的主梁跨中弯矩进行研... 详细信息

近年来,小箱梁加宽桥在高速公路改扩建中得到广泛应用,而新旧桥梁的拼接方式是桥梁加宽的关键。以山西昔榆高速拼宽桥为工程背景,利用数值模拟方法,首先论述了减少不均匀沉降的应对措施;其次对不同湿接缝拼接宽度下的主梁跨中弯矩进行研究;最后对比分析了湿接缝铰接和刚接两种拼接方式的受力性能。结果表明,拼接后拼接处相邻的主梁受力性能影响最大;拼接湿接缝的宽度越小,拼接处连接刚度越大,其受力越合理,且宽度在40~60 cm范围时可以有效降低旧桥弯矩,提高新旧桥梁整体受力;与湿接缝铰接拼接方式相比,刚接拼接方式下加宽桥的受力性能更为合理。

关键词：桥梁工程改扩建工程加宽桥湿接缝拼接刚接拼接方式应力分析

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