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Altered amplitudes of low-frequency fluctuations in primary open angle glaucoma patients:a resting-state fMRI study
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作者 Yi Huang Hong-Dou Luo +7 位作者 Yong-Qiang Shu Feng Ouyang Yu-Ning Song Yuan-Yuan Wang xue-Qing Yu Chan Xiong Lu Yang xu zhang 《International Journal of Ophthalmology(English edition)》 2026年第2期291-301,共11页
AIM:To study the relationships between amplitude of low-frequency fluctuations(ALFF)changes and clinical ophthalmic parameters in patients with primary open angle glaucoma(POAG)and analyze the diagnostic value of ALFF... AIM:To study the relationships between amplitude of low-frequency fluctuations(ALFF)changes and clinical ophthalmic parameters in patients with primary open angle glaucoma(POAG)and analyze the diagnostic value of ALFF.METHODS:Twenty-four POAG patients and 24 healthy controls(HCs)underwent resting-state functional magnetic resonance imaging(rs-fMRI).Nonparametric rank-sum tests were used to compare the ALFF values in the slow-4 and slow-5 bands,and Spearman or Pearson correlation analysis was used to assess the correlation between ALFF changes and clinical ophthalmic parameters in POAG patients.Receiver operating characteristic(ROC)curves were used to evaluate the diagnostic performance of the ALFF.RESULTS:There were 16 males in POAG patients(median age 48y)and 12 males in HCs(median age 39y).Compared with HCs,POAG patients presented increased or decreased ALFF values in different brain regions,and similar changes were observed in mild POAG patients.The ALFF values were correlated with retinal nerve fiber layer(RNFL)thickness,inner limiting membrane-retinal pigment epithelium thickness changes and the degree of visual field defects.Analysis of the diagnostic value of the ALFF via ROC curves revealed that the right medial frontal gyrus[area under the curve(AUC)=0.9063]and superior frontal gyrus(AUC=0.9097)had better diagnostic value than did the optic disc area(AUC=0.8019),visual field index(VFI%,AUC=0.8988)and macular parameters.CONCLUSION:POAG patients present altered cortical function that is significantly correlated with the optic nerve and retinal thickness and had good diagnostic value,which may reflect the underlying neuropathological mechanism of POAG. 展开更多
关键词 primary open angle glaucoma restingstate functional magnetic resonance imaging low-frequency amplitude neurodegenerative disease
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肿瘤外科学发展现状与趋势分析
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作者 张旭 顾良友 贾通宇 《中国科学基金》 北大核心 2025年第1期50-59,共10页
肿瘤外科学作为肿瘤综合治疗的重要支柱,经历了从传统开放手术向腹腔镜手术和机器人手术的变革。近年来,依托人工智能、大数据、5G通信和分子生物技术等前沿科技,推动了肿瘤外科学向远程化、精准化和智能化迈进。远程手术技术有望实现... 肿瘤外科学作为肿瘤综合治疗的重要支柱,经历了从传统开放手术向腹腔镜手术和机器人手术的变革。近年来,依托人工智能、大数据、5G通信和分子生物技术等前沿科技,推动了肿瘤外科学向远程化、精准化和智能化迈进。远程手术技术有望实现跨区域医疗资源共享,为偏远地区患者提供优质诊疗服务;基于CRISPR/Cas9的“分子手术刀”则为基因层面的精准干预打开了新局面;AI在术前影像分析、手术路径规划及风险预测中的应用提升了个性化治疗水平。然而,医疗资源分配不均、技术推广难以及伦理法律问题,仍是肿瘤外科学面临的挑战。展望未来,肿瘤外科学将在可解释性AI、多模态成像和自主手术等新技术驱动下,进一步提升精准性与智能化水平,推动整体治疗模式的革新,最终为患者带来更高的生存率与生活质量。 展开更多
关键词 肿瘤 外科学 微创手术 人工智能 精准外科
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锂离子电池富锂层状正极材料Li-Ni-Mn-O应变机理研究 被引量:1
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作者 刘继洪 祝佳鹏 +4 位作者 张旭 张纪阳 黄超洋 贾桂霄 安胜利 《化学学报》 北大核心 2025年第2期101-109,共9页
富锂层状氧化物(LLOs)中Li_(2)MnO_(3)畴的聚集和晶格释氧导致了严重的容量/电压衰减,阻碍了其商业化应用.本工作设计了Co渗透(LNCMO-P)和未渗透(LNCMO-n P) Li_(1.17)Ni_(0.165)Co_(0.165)Mn0.5O_(2)两种模型,使用第一性原理计算方法... 富锂层状氧化物(LLOs)中Li_(2)MnO_(3)畴的聚集和晶格释氧导致了严重的容量/电压衰减,阻碍了其商业化应用.本工作设计了Co渗透(LNCMO-P)和未渗透(LNCMO-n P) Li_(1.17)Ni_(0.165)Co_(0.165)Mn0.5O_(2)两种模型,使用第一性原理计算方法研究了Co渗透对氧化过程、脱锂结构及结构稳定性和晶格畸变的影响.研究结果表明,通过调控氧空位浓度可将Co渗透到Li_(2)MnO_(3)相.Co渗透缓解了Li_(2)MnO_(3)与LiTMO_(2)两相应力畸变,抑制了由不均匀的电化学活动和结构演变产生的晶格应变.Co的渗透激活了界面氧参与电荷补偿,分散了氧的氧化,分担了Li-O-Li构型中氧的氧化压力,改善由于晶格氧过度氧化面临不可逆氧气析出的问题.此外Ni—O强共价键引起了高自旋Co电子态出现,缓减了充电引起的体积膨胀.本工作为设计具有高性能结构稳定的富锂正极材料提供了理论基础. 展开更多
关键词 富锂层状氧化物 Li2MnO3相 Co渗透 应力 第一性原理计算
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再生水利用生态缓冲区的概念、功能及效益分析
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作者 齐娅荣 王飞鹏 +9 位作者 魏东斌 杨钻 陈卓 巫寅虎 王玉明 安麒文 陆韻 苑宝玲 徐章 胡洪营 《生态学报》 北大核心 2025年第21期10307-10319,共13页
污水再生利用是应对水资源短缺问题的有效措施。然而,再生水中残留的氮、磷等常规污染物以及内分泌干扰物、抗生素等新污染物,在长期利用过程中可能引发潜在的生态风险和健康风险。当前再生水深度处理工艺面临成本高、能耗大等问题,生... 污水再生利用是应对水资源短缺问题的有效措施。然而,再生水中残留的氮、磷等常规污染物以及内分泌干扰物、抗生素等新污染物,在长期利用过程中可能引发潜在的生态风险和健康风险。当前再生水深度处理工艺面临成本高、能耗大等问题,生态处理技术可弥补上述不足。通过生态处理,再生水的水质进一步得到改善,从而降低生态风险、促进生态融合,有助于维持生态平衡和保障生态安全。基于再生水生态利用探讨设置生态缓冲区的必要性,系统阐述了再生水利用生态缓冲区的概念内涵及主要类型(包括再生水补给口湿地、受纳水体的湖(河)滨带、再生水与受纳水体的混合区),强调了该生态缓冲区的定位;以人工湿地为例探讨了再生水利用生态缓冲区对再生水中残留污染物(氮、磷、有机物、重金属、抗生素以及病原微生物)的去除效果;深入分析了人工湿地再生水利用生态缓冲区在水质净化和水征变化的核心机制,包括物理吸附、化学转化、植物吸收、微生物降解等多重作用,并详细阐述了再生水的生态融合机制;探讨了再生水利用生态缓冲区在提高再生水的生态安全性、改善再生水的生态相融性以及丰富水环境的生态多样性等方面的综合生态效益,能够实现将再生水厂生产的“工程水”融合转变为更接近天然的“生态水”。研究结果为再生水的安全利用提供科学依据,从而促进水资源的可持续利用,并保障水环境与水生态安全。 展开更多
关键词 再生水生态利用 再生水利用生态缓冲区 生态缓冲区功能 生态缓冲区类型 生态缓冲区效益
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临床问题驱动的肿瘤研究新范式
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作者 朱波 石嵘 +3 位作者 姚刚 张旭 陈孝平 王红阳 《中国科学基金》 北大核心 2025年第1期2-13,共12页
恶性肿瘤是威胁人民生命健康的重大疾病,不仅给患者带来巨大痛苦,也给社会经济发展造成了沉重负担。我国肿瘤患者五年生存率远低于欧美国家,凸显出我国肿瘤防控工作仍有待加强。当今世界正进入大科学时代,肿瘤研究既迎来了前所未有的机... 恶性肿瘤是威胁人民生命健康的重大疾病,不仅给患者带来巨大痛苦,也给社会经济发展造成了沉重负担。我国肿瘤患者五年生存率远低于欧美国家,凸显出我国肿瘤防控工作仍有待加强。当今世界正进入大科学时代,肿瘤研究既迎来了前所未有的机遇,也面临着诸多挑战。传统的以知识探索为导向的研究范式限制了科研成果向临床应用的有效转化。为提升肿瘤科研转化效率,提升我国肿瘤防治综合实力,国家自然科学基金委员会成功举办了双清论坛“临床问题驱动的肿瘤研究新范式”。此次论坛深刻剖析了肿瘤预防、诊断、治疗及药物研发等领域的核心难题,并深入探讨了“肿瘤研究新范式”的核心内涵与显著特征。本文旨在总结论坛达成的共识,概述肿瘤防治的现状、面临的重大科学问题、传统范式的局限性以及新范式的内涵特征,为推动我国肿瘤研究高质量发展和科学基金前瞻布局提供理论支撑。 展开更多
关键词 肿瘤防治 临床问题 转化研究 新范式
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超薄柔性有机太阳能电池的研究进展 被引量:1
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作者 孙凌亚 刘世钊 +5 位作者 张旭 马笑 高欢欢 阚媛媛 孙延娜 高珂 《高分子学报》 北大核心 2025年第7期1039-1062,共24页
超薄柔性有机太阳能电池(ultrathin and flexible organic solar cells,UF-OSCs)凭借其卓越的柔韧性及高功率重量比,在可穿戴电子设备、柔性显示技术等领域展现出巨大的应用潜力.然而,UF-OSCs的光电转换效率(PCE)与刚性器件相比,仍存在... 超薄柔性有机太阳能电池(ultrathin and flexible organic solar cells,UF-OSCs)凭借其卓越的柔韧性及高功率重量比,在可穿戴电子设备、柔性显示技术等领域展现出巨大的应用潜力.然而,UF-OSCs的光电转换效率(PCE)与刚性器件相比,仍存在较大的提升空间.为了提高UF-OSCs的性能,国内外研究人员从器件的材料及结构等方面展开了深入研究.其中,超薄柔性透明电极(UFTE)作为器件组成的关键部分,其性能对电池的整体效率和稳定性有着直接影响.本文以UFTE为切入点,结合界面层和器件结构工程等多种策略,对UF-OSCs的最新研究进展进行了详细分析.此外,还简要介绍了大面积UF-OSCs的潜在应用.最后,提出了UF-OSCs进一步发展所面临的挑战,并展望了其在柔性电源领域的应用前景. 展开更多
关键词 超薄柔性有机太阳能电池 超薄柔性透明电极 功率重量比 机械稳定性
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Expert consensus on the prevention and treatment of enamel demineralization in orthodontic treatment 被引量:1
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作者 Lunguo Xia Chenchen Zhou +29 位作者 Peng Mei Zuolin Jin Hong He Lin Wang Yuxing Bai Lili Chen Weiran Li Jun Wang Min Hu Jinlin Song Yang Cao Yuehua Liu Benxiang Hou Xi Wei Lina Niu Haixia Lu Wensheng Ma Peijun Wang Guirong zhang Jie Guo Zhihua Li Haiyan Lu Liling Ren Linyu xu Xiuping Wu Yanqin Lu Jiangtian Hu Lin Yue xu zhang Bing Fang 《International Journal of Oral Science》 2025年第2期155-165,共11页
Enamel demineralization,the formation of white spot lesions,is a common issue in clinical orthodontic treatment.The appearance of white spot lesions not only affects the texture and health of dental hard tissues but a... Enamel demineralization,the formation of white spot lesions,is a common issue in clinical orthodontic treatment.The appearance of white spot lesions not only affects the texture and health of dental hard tissues but also impacts the health and aesthetics of teeth after orthodontic treatment.The prevention,diagnosis,and treatment of white spot lesions that occur throughout the orthodontic treatment process involve multiple dental specialties.This expert consensus will focus on providing guiding opinions on the management and prevention of white spot lesions during orthodontic treatment,advocating for proactive prevention,early detection,timely treatment,scientific follow-up,and multidisciplinary management of white spot lesions throughout the orthodontic process,thereby maintaining the dental health of patients during orthodontic treatment. 展开更多
关键词 white spot lesions enamel demineralizationthe enamel demineralization orthodontic treatment diagnosis white spot lesionsis dental hard tissues prevention
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Antimicrobial resistance crisis:could artificial intelligence be the solution? 被引量:1
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作者 Guang-Yu Liu Dan Yu +4 位作者 Mei-Mei Fan xu zhang Ze-Yu Jin Christoph Tang Xiao-Fen Liu 《Military Medical Research》 2025年第1期72-95,共24页
Antimicrobial resistance is a global public health threat,and the World Health Organization(WHO)has announced a priority list of the most threatening pathogens against which novel antibiotics need to be developed.The ... Antimicrobial resistance is a global public health threat,and the World Health Organization(WHO)has announced a priority list of the most threatening pathogens against which novel antibiotics need to be developed.The discovery and introduction of novel antibiotics are time-consuming and expensive.According to WHO’s report of antibacterial agents in clinical development,only 18 novel antibiotics have been approved since 2014.Therefore,novel antibiotics are critically needed.Artificial intelligence(AI)has been rapidly applied to drug development since its recent technical breakthrough and has dramatically improved the efficiency of the discovery of novel antibiotics.Here,we first summarized recently marketed novel antibiotics,and antibiotic candidates in clinical development.In addition,we systematically reviewed the involvement of AI in antibacterial drug development and utilization,including small molecules,antimicrobial peptides,phage therapy,essential oils,as well as resistance mechanism prediction,and antibiotic stewardship. 展开更多
关键词 Antibiotic Artificial intelligence(AI) Clinical development Machine learning(ML) Antimicrobial peptide Phage therapy Antibiotic stewardship
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Element Transfer Reaction theory:Scientific connotation and its applications in chemical industry 被引量:1
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作者 Hongen Cao Xinrui Xiao +2 位作者 xu zhang Yiyang zhang Lei Yu 《Chinese Chemical Letters》 2025年第9期4-7,共4页
Element Transfer Reaction(ETR)theory is a new fundamental theory guiding the design of synthetic routes.It analyses problems from a brand-new perspective of element circulation,decomposing the factors affecting synthe... Element Transfer Reaction(ETR)theory is a new fundamental theory guiding the design of synthetic routes.It analyses problems from a brand-new perspective of element circulation,decomposing the factors affecting synthetic efficiency into three elements:element sources,driving force,and output.Different from the retrosynthetic analysis method and the atom economy theory,the ETR theory places more emphasis on examining the problem as a whole and comprehensively considering various factors involved in industrial applications.This perspective intends to elaborate on the scientific connotation of the ETR theory and explore its characteristics by discussing the practical application cases. 展开更多
关键词 Element Transfer Reaction theory Element source Driving force OUTPUT Energy conservation Atom economy
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Development of a coupled model to simulate and assess arsenic contamination and impact factors in the Jinsha River Basin,China 被引量:1
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作者 Yidian Sun xu zhang +5 位作者 Hong Peng Wenting Zhou Anna Jiang Feng Zhou Hao Wang Wanshun zhang 《Journal of Environmental Sciences》 2025年第1期50-61,共12页
With the increasing severity of arsenic(As)pollution,quantifying the environmental behavior of pollutant based on numerical model has become an important approach to determine the potential impacts and finalize the pr... With the increasing severity of arsenic(As)pollution,quantifying the environmental behavior of pollutant based on numerical model has become an important approach to determine the potential impacts and finalize the precise control strategies.Taking the industrialintensive Jinsha River Basin as typical area,a two-dimensional hydrodynamic water quality model coupled with Soil andWater Assessment Tool(SWAT)model was developed to accurately simulate the watershed-scale distribution and transport of As in the terrestrial and aquatic environment at high spatial and temporal resolution.The effects of hydro-climate change,hydropower station construction and non-point source emissions on Aswere quantified based on the coupled model.The result indicated that higher As concentration areas mainly centralized in urban districts and concentration slowly decreased from upstream to downstream.Due to the enhanced rainfall,the As concentration was significantly higher during the rainy season than the dry season.Hydro-climate change and the construction of hydropower station not only affected the dissolved As concentration,but also affected the adsorption and desorption of As in sediment.Furthermore,As concentration increased with the input of non-point source pollution,with the maximum increase about 30%,resulting that non-point sources contributed important pollutant impacts to waterways.The coupled model used in pollutant behavior analysis is generalwith high potential application to predict and mitigate water pollution. 展开更多
关键词 Watershed system ARSENIC Modeling DISTRIBUTION Hydro-climate change Non-point source pollution
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Advances in the treatment of metastatic prostate cancer in China 被引量:1
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作者 Baojun Wang Zhenhua Liu +1 位作者 Luyao Yang xu zhang 《Cancer Biology & Medicine》 2025年第5期433-438,共6页
Prostate cancer (PC) is among the most common cancer diagnoses in men worldwide and the fifth leading cause of cancer-related deaths. Approximately 1.5 million new cases of PC were reported worldwide in 2022 with near... Prostate cancer (PC) is among the most common cancer diagnoses in men worldwide and the fifth leading cause of cancer-related deaths. Approximately 1.5 million new cases of PC were reported worldwide in 2022 with nearly 400,000 associated deaths1. Notably, the incidence of PC in China has increased substantially compared to the global average2. 展开更多
关键词 prostate cancer INCIDENCE MORTALITY China metastatic prostate cancer TREATMENT
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Efficacy of recombinant human thrombopoietin in patients with acute-on-chronic liver failure and thrombocytopenia:A prospective,open-label study 被引量:1
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作者 Gang Liu Fei Tang +6 位作者 Tao Wang Jun-Qing Yan Feng-Hui Li Fu-Shuang Ha xu zhang Li Jing Jing Liang 《World Journal of Gastroenterology》 2025年第14期61-70,共10页
BACKGROUND Patients with acute-on-chronic liver failure(ACLF)have a high mortality rate,poor prognosis,and often experience concurrent thrombocytopenia and bleeding events.AIM To evaluate the efficacy and safety of re... BACKGROUND Patients with acute-on-chronic liver failure(ACLF)have a high mortality rate,poor prognosis,and often experience concurrent thrombocytopenia and bleeding events.AIM To evaluate the efficacy and safety of recombinant human thrombopoietin(rhTPO)in patients with ACLF with concomitant severe thrombocytopenia.METHODS This was a prospective,open-label study.We assigned 70 ACLF patients with severe thrombocytopenia into the rhTPO group and control group,with 35 patients in each group.Patients in the rhTPO group received subcutaneous injections of rhTPO at a dose of 15000 IU/day for 7 consecutive days,while patients in the control group did not receive rhTPO treatment.The primary endpoint was the proportion of patients with platelet count>50×10^(9)/L on day 14.RESULTS The proportion of patients with platelet count>50×10^(9)/L on day 14 was 60.7%in the rhTPO group,which was significantly higher than that(12.0%)in the control group(P<0.001).The platelet count in the rhTPO group on day 14 was 64×10^(9)/L,exceeding the baseline of 28×10^(9)/L.Compared to the control group,the rhTPO group exhibited a significant increase in platelet count from baseline(P<0.05).Model for end-stage liver disease score,albumin level and international normalized ratio improved significantly from baseline on day 14 after rhTPO injection.The concentrations of serum thrombopoietin and hepatocyte growth factor in the rhTPO group after 7 days were 143.7 and 195.4 pg/mL,respectively,showing a significant increase from baseline(P<0.05).Eight(22.9%)patients had bleeding events in the control group compared with four(11.4%)in the rhTPO group.The incidence of 90-day mortality was also higher in the control group(6,17.1%)than that in the rhTPO group(3,8.6%).CONCLUSION rhTPO significantly increased the platelet count in ACLF patients with thrombocytopenia and reduce the occurrence of bleeding events,with a good safety profile. 展开更多
关键词 Recombinant human thrombopoietin Acute-on-chronic liver failure THROMBOCYTOPENIA Hepatocyte growth factor PROGNOSIS
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The strength-ductility synergy of magnesium matrix nanocomposite achieved by a dual-heterostructure 被引量:1
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作者 Lingling Fan Yukai Xiong +7 位作者 Ying Zeng Ran Ni Yuwenxi zhang Lingbao Ren Hajo Dieringa Yuanding Huang Gaofeng Quan xu zhang 《Journal of Materials Science & Technology》 2025年第12期296-314,共19页
This study aims to achieve a synergy of strength and ductility in magnesium-based nanocomposite materials through the design of a dual-heterostructure. Utilizing ball milling and hot extrusion, a nano-TiC/AZ61 composi... This study aims to achieve a synergy of strength and ductility in magnesium-based nanocomposite materials through the design of a dual-heterostructure. Utilizing ball milling and hot extrusion, a nano-TiC/AZ61 composite featuring particle-rare coarse grain (CG) and particle-rich fine grain (FG) zones was successfully fabricated. Experimental results demonstrated that compared with the homogeneous structure, the dual-heterostructure composite achieved a significant increase in elongation by 116 % and a remarkable 165 % improvement in the strength-ductility product (SDP), while maintaining a high ultimate tensile strength (UTS) of 417±4 MPa. This substantial performance enhancement is primarily attributed to the additional strain hardening induced by hetero-deformation-induced (HDI) strain hardening and crack-blunting capabilities, as elucidated by microstructural characterization and crystal plasticity finite element modeling (CPFEM). Notably, the strain hardening contribution from the CG zones at the early stage of deformation (≤ 45 % of total plastic deformation amount) is minimal but increases significantly during the subsequent deformation stages. The dislocation increment rate in CG zones (219 %) is observed to be more than double that in FG zones (95 %), attributed to the large grain size and low dislocation density in CG zones, which provide more space for dislocation storage. In addition, the aggravated deformation inhomogeneity as deformation progresses leads to an increase in geometrically necessary dislocations (GNDs) generation near the heterogeneous interface, thereby enhancing HDI hardening. Fracture mechanism analysis indicated that the cracks mainly initiate in the FG region and are effectively blunted upon their propagation to the CG region, necessitating increased energy consumption and indicating higher fracture toughness for the dual-heterostructure composites. This study validates the effectiveness of the dual-heterostructure design in magnesium-based composites, providing a novel understanding of the deformation mechanism through both experimental analysis and CPFEM, paving the way for the development of high-performance, lightweight structural materials. 展开更多
关键词 HETEROSTRUCTURE Strengthening mechanism Strength-ductility synergy Fracture mechanism MAGNESIUM
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高性能铝电池负极设计:挑战与策略
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作者 曾杉杉 王同波 +2 位作者 梁李斯 张旭 尉海军 《化学进展》 北大核心 2025年第6期827-842,共16页
由于铝金属具有高体积/质量比容量、高安全和低成本等优势,铝电池成为目前新型电化学储能器件的研究热点之一。高性能电池材料是制约铝电池发展的关键因素,相较于多样的正极材料,铝负极设计是铝电池的共性关键问题。然而,铝负极存在表... 由于铝金属具有高体积/质量比容量、高安全和低成本等优势,铝电池成为目前新型电化学储能器件的研究热点之一。高性能电池材料是制约铝电池发展的关键因素,相较于多样的正极材料,铝负极设计是铝电池的共性关键问题。然而,铝负极存在表面钝化、局部腐蚀、枝晶生长等问题,极大影响了铝电池的电化学性能。本文针对上述问题,首先从反应机制角度分析了影响铝负极性能的关键因素,综述近年来铝负极设计改性的重要研究进展,分析可有效改善铝负极性能的重要策略,并探讨其对铝电池电化学性能的优化效应及机理。最后,针对铝负极设计优化的挑战性问题和发展趋势进行展望,为构建高性能铝电池提供参考。 展开更多
关键词 铝电池 铝负极设计 表面钝化 局部腐蚀 枝晶生长
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共轴式永磁同步电机设计与仿真
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作者 徐璋 邓涛 柳平 《科学技术与工程》 北大核心 2025年第21期8926-8935,共10页
随着飞机多电化/全电化趋势的推进,多电发动机成为核心技术。设计了一种基于新型转缸式摆盘发动机的共轴高转矩永磁同步电机,实现发动机与电机一体化。首先,根据发动机性能参数和传动轴的关系,确定共轴结构和电机尺寸。其次,通过有限元... 随着飞机多电化/全电化趋势的推进,多电发动机成为核心技术。设计了一种基于新型转缸式摆盘发动机的共轴高转矩永磁同步电机,实现发动机与电机一体化。首先,根据发动机性能参数和传动轴的关系,确定共轴结构和电机尺寸。其次,通过有限元软件分析扁线绕组层数和尺寸对铜损的抑制作用。同时,采用转子分段斜极、辅助槽和田口算法对电机拓扑结构进行优化,降低电机齿槽转矩、额定转矩脉动、定子铁损及气隙磁密畸变率,显著提升电磁性能。最后,对电机各工况仿真,计算驱动与发电效率,并验证在大电流条件下电机不发生退磁现象。结果表明:电机在6000 r/min额定转速下,输出转矩200 N·m,并处于高效运行区,电机峰值转矩可达400 N·m,高速发电恒功率区功率达到250 kW,满足设计规范要求。 展开更多
关键词 永磁电机 摆盘发动机 共轴结构 田口算法 电磁性能
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糖对植物花色素苷合成和积累的调节 被引量:16
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作者 李倩 张立军 +2 位作者 张旭 阮燕晔 崔震海 《生命的化学》 CAS CSCD 北大核心 2009年第2期218-222,共5页
糖是植物体中影响花色素苷合成和积累的重要因子之一。该文介绍了花色素苷的基本结构和可溶性糖积累与花色素苷合成的关系,并从糖转运蛋白、糖信号转导和基因表达等方面总结了可溶性糖调节花色素苷生物合成和积累的研究进展。
关键词 花色素苷 生物合成 积累
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基于粒子群算法的风光互补发电系统配置优化设计 被引量:24
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作者 徐璋 李莎 +3 位作者 胡小坚 冯彦皓 陈明 符叶晔 《浙江工业大学学报》 CAS 北大核心 2018年第6期650-655,共6页
粒子群算法(Particle swarm optimization,简称PSO)模型简洁,具有优异的探索效率、良好的收敛性及精度,与其他优化算法相比具有令人瞩目的优异性。通过将粒子群算法应用于由太阳光、风力发电等构成的可再生能源混合发电系统的最优化配... 粒子群算法(Particle swarm optimization,简称PSO)模型简洁,具有优异的探索效率、良好的收敛性及精度,与其他优化算法相比具有令人瞩目的优异性。通过将粒子群算法应用于由太阳光、风力发电等构成的可再生能源混合发电系统的最优化配置研究中,并通过实际的应用完成在以系统综合成本最小的约束条件下,对系统各构成模块的规格进行优化分析。通过对某工业园区进行风光互补发电系统优化,即分别对风光互补发电系统、单一风力发电系统、单一光伏阵列发电系统这3种优化方案进行经济性分析和技术性分析,进行优化设计。结果表明:基于粒子群算法的风光互补发电系统优化设计在兼顾满足负载要求的情况下,达到较好的经济性,适宜推广此种可再生能源发电方式。 展开更多
关键词 粒子群算法 风光互补优化 发电量 负载满足率
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Long-Term Continuous Light Exposure Affects Body Weight and Blood Glucose Associated with Inflammation in Female Rats 被引量:1
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作者 xuezhi Kang Lina Jia +4 位作者 xu zhang Yaming Li Yi Chen xueyong Shen Yaochi Wu 《Journal of Biosciences and Medicines》 2016年第9期11-24,共14页
Studies have indicated that night lights interfere with the circadian rhythm in the human body and threaten human health. Our previous studies indicated that continuous light exposure severely damages the reproductive... Studies have indicated that night lights interfere with the circadian rhythm in the human body and threaten human health. Our previous studies indicated that continuous light exposure severely damages the reproductive endocrine system of female rats resembles polycystic ovary syndrome in women. In this study, we used the continuous measurement method to observe changes in the basal physiological indicators of female rats in an abnormal light exposure environment. Our study results indicated that in female rats: 1) the body temperature first continuously and gradually increased followed by a gradually decrease;2) the increase in body weight slowed down at the late stage of the experimental process;3) the random blood glucose level increased, and the fasting serum insulin level decreased;and 4) the serum C-reactive protein level increased. Our study investigated for the first time the correlation between the duration of continuous light exposure in female rats and the continuously measured basal physiological indicators and preliminarily discussed the effect of continuous light exposure on female basal metabolism and the possible inflammation mechanism. We propose that long-term continuous exposure to night lights in females severely damages their immune and metabolic systems. 展开更多
关键词 Continuous Light Exposure Body Weight Blood Glucose INFLAMMATION Comparative Study
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Loop-Current Fluctuations Mediated Chiral d-Wave Pairing in Kagome Lattice
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作者 Qi-Fang Li Gaopei Pan +4 位作者 xu zhang Satoru Nakatsuji Weilun Jiang Xiao Yan xu Xianxin Wu 《Chinese Physics Letters》 2025年第5期123-139,共17页
Recent various experiments have provided evidence supporting the emergence of loop-current order in kagome metals. Particularly superconductivity in AV_(3)Sb_(5) is significantly enhanced when this charge order is sup... Recent various experiments have provided evidence supporting the emergence of loop-current order in kagome metals. Particularly superconductivity in AV_(3)Sb_(5) is significantly enhanced when this charge order is suppressed by pressure or doping. Distinct from magnetic order, loop-current order does not couple directly to spin and thus whether such fluctuations can enhance superconductivity remains elusive. We design a sign problem-free bilayer kagome model coupled to quantum Ising spins through bond currents and perform determinant quantum Monte Carlo simulations to explore single-particle properties and superconductivity arising from 2 × 2 loopcurrent fluctuations. We find that this loop-current order induces intriguing band folding, band broadening,and gap opening around saddle points. Remarkably, our pairing susceptibility analysis identifies a dominant enhancement of superconductivity due to loop-current fluctuations, with the dominant pairing being the chiral d-wave channel. This pairing primarily occurs within the intra-sublattice channel and involves third nearestneighbor sites, attributed to the unique sublattice texture associated with van Hove singularities. We also discuss potential experimental implications for kagome superconductors. 展开更多
关键词 kagome metals quantum ising spins quantum monte carlo simulations bond current enhance superconductivity chiral d wave pairing loop current fluctuations kagome lattice
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