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Ti含量对热镀55wt.%Al-Zn镀层组织的影响
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作者 张志坚 徐学明 +3 位作者 唐兴昌 惠洋 刘小华 李坤宇 《兰州理工大学学报》 北大核心 2026年第1期8-14,共7页
为研究Ti对热镀55wt.%Al-Zn镀层组织的影响,通过配置不同Ti含量55wt.%Al-Zn热浸镀锌铝液对钢基板进行热浸镀实验,利用光学显微镜(OM)、扫描电镜(SEM)及能谱仪(EDS),对不同Ti含量铝锌镀层的表面、截面及过渡层组织进行分析.结果表明:不... 为研究Ti对热镀55wt.%Al-Zn镀层组织的影响,通过配置不同Ti含量55wt.%Al-Zn热浸镀锌铝液对钢基板进行热浸镀实验,利用光学显微镜(OM)、扫描电镜(SEM)及能谱仪(EDS),对不同Ti含量铝锌镀层的表面、截面及过渡层组织进行分析.结果表明:不同Ti含量表面锌花组织结构基本一致,镀层表面锌花及合金层组织均由富Al相、富Zn相、富Si相及Al-Zn-Fe-Si化合物相构成;当Ti质量分数低于0.035%时,镀层锌花尺寸随Ti含量的增高而显著减小,含Ti镀层组织相对细小且致密;Ti的添加能够在镀液凝固过程中增加形核点,有助于锌花尺寸减小及细化镀层合金晶粒尺寸. 展开更多
关键词 铝锌镀层 TI含量 镀层组织 锌花 晶粒细化
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基于H-C方法的地震发震断层快速识别——以2017年12月19日辽宁海城M4.4地震为例
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作者 戴盈磊 张文静 +2 位作者 惠杨 王承伟 程应伟 《华南地震》 2026年第1期33-42,共10页
应用“先粗后细”的网格划分方案和CAP方法反演2017年12月19日辽宁海城M4.4地震震源机制解。基于震源—质心(H-C)方法快速测定其发震断层面。利用改进的DBSCAN算法自动识别海城、岫岩地区主要断层的几何参数,并结合该地区构造应力场给... 应用“先粗后细”的网格划分方案和CAP方法反演2017年12月19日辽宁海城M4.4地震震源机制解。基于震源—质心(H-C)方法快速测定其发震断层面。利用改进的DBSCAN算法自动识别海城、岫岩地区主要断层的几何参数,并结合该地区构造应力场给出它们的滑动性质。结果表明:海城M4.4地震最优质心位置为(40.4672°N,123.1494°E)。震源机制解走向288°,标准差5.80°,倾角81°,标准差5.69°,滑动角-13°,标准差5.71°,矩震级MW4.34,质心深度11 km,标准差0.38 km。联合P波初动解走向34.10°,倾角67.48°,滑动角-159.64°,及其他学者的资料得到该地震震源机制中心解为走向287.51°,倾角78.66°,滑动角-22.90°。以各机构给出的震源参数和不同震源机制进行的全部25次快速识别检验均显示震源机制解NWW走向的节面II是本次海城M4.4地震的主断层面。自动识别得到3个走滑断层和1个正断层。其中断层A和断层C分别是1975年海城MS7.3地震和1999年岫岩MS5.4地震的发震构造,断层B和断层D的参数特征也与前人的认识相符。 展开更多
关键词 海城M4.4地震 H-C方法 CAP方法 震源机制解 发震断层 改进的DBSCAN
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退火温度对新型铁素体不锈钢组织与性能的影响
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作者 王长波 李欢欢 +3 位作者 保先恒 王建泽 惠洋 马金元 《金属热处理》 北大核心 2026年第2期245-250,共6页
通过真空感应熔炼制备了添加Mn和V元素的SUS410L-N新型铁素体不锈钢,系统探究了退火温度(720、820、890℃)对其相变特性、微观组织及拉伸性能的影响。结果表明,退火处理可显著降低残余应力和位错密度,晶粒尺寸随退火温度升高呈现先增后... 通过真空感应熔炼制备了添加Mn和V元素的SUS410L-N新型铁素体不锈钢,系统探究了退火温度(720、820、890℃)对其相变特性、微观组织及拉伸性能的影响。结果表明,退火处理可显著降低残余应力和位错密度,晶粒尺寸随退火温度升高呈现先增后减的趋势,820℃退火时增至3.90μm,而890℃退火时因γ→α相变诱导再结晶使晶粒细化至3.12μm。820℃退火后形成约200 nm椭球形析出物,890℃退火时析出物尺寸减小至20~50 nm。随退火温度升高,强度由热轧态先降低随后升高,断裂总延伸率逐渐升高。890℃退火试样综合力学性能优异,这归因于高密度大角度晶界(HAGBs)、细晶组织以及纳米级析出物的协同作用,实现了强度与塑性的最佳匹配。 展开更多
关键词 铁素体不锈钢 退火温度 显微组织 拉伸性能
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Research progress on the Sonic Hedgehog signaling pathway in the central nervous system:Novel insights
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作者 Nuokun Li Shiyi Wen +9 位作者 Dandan Li Yaning Shi Zhigang Mei Danhong Liu hui yang Yuhong Wang Xiaoyuan Lin Yun Xiang Hongbo Wen Pan Meng 《Neural Regeneration Research》 2026年第6期2125-2136,共12页
Over the past few decades,the Sonic Hedgehog protein has become a pivotal player in many biological processes,including tumourigenesis,embryonic development,and protective mechanisms after cerebral damage.The Sonic He... Over the past few decades,the Sonic Hedgehog protein has become a pivotal player in many biological processes,including tumourigenesis,embryonic development,and protective mechanisms after cerebral damage.The Sonic Hedgehog signaling pathway is crucial in the central nervous system,with implications in a diverse range of diseases,including Parkinson's disease,Alzheimer's disease,spinal cord injury,traumatic brain injury,depression,Sonic Hedgehog medulloblastoma,and stroke.In this comprehensive review,we examined Sonic Hedgehog from the perspective of canonical and non-canonical pathways,elucidating their complex connections to the central nervous system.Subsequently,we summarize the latest advancements in drug therapies that offer novel strategies for treating neurological diseases by modulating the Sonic Hedgehog protein.Finally,we summarize and extend the technologies and tools for studying the Sonic Hedgehog signaling field,with the aim of providing new research ideas and methods. 展开更多
关键词 Alzheimer's disease CANONICAL central nervous system disease drug therapy neural regeneration non-canonical Sonic Hedgehog Sonic Hedgehog medulloblastoma stroke
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Advanced isoconversional kinetic analysis of lepidolite sulfation product decomposition reactions for selectively extracting lithium
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作者 Yubo Liu Baozhong Ma +4 位作者 Jiahui Cheng Xiang Li hui yang Chengyan Wang Yongqiang Chen 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期217-227,共11页
The sulfation and decomposition process has proven effective in selectively extracting lithium from lepidolite.It is essential to clarify the thermochemical behavior and kinetic parameters of decomposition reactions.A... The sulfation and decomposition process has proven effective in selectively extracting lithium from lepidolite.It is essential to clarify the thermochemical behavior and kinetic parameters of decomposition reactions.Accordingly,comprehensive kinetic study by employing thermalgravimetric analysis at various heating rates was presented in this paper.Two main weight loss regions were observed during heating.The initial region corresponded to the dehydration of crystal water,whereas the subsequent region with overlapping peaks involved complex decomposition reactions.The overlapping peaks were separated into two individual reaction peaks and the activation energy of each peak was calculated using isoconversional kinetics methods.The activation energy of peak 1 exhibited a continual increase as the reaction conversion progressed,while that of peak 2 steadily decreased.The optimal kinetic models,identified as belonging to the random nucleation and subsequent growth category,provided valuable insights into the mechanism of the decomposition reactions.Furthermore,the adjustment factor was introduced to reconstruct the kinetic mechanism models,and the reconstructed models described the kinetic mechanism model more accurately for the decomposition reactions.This study enhanced the understanding of the thermochemical behavior and kinetic parameters of the lepidolite sulfation product decomposition reactions,further providing theoretical basis for promoting the selective extraction of lithium. 展开更多
关键词 LITHIUM LEPIDOLITE decomposition reactions KINETICS isoconversional analysis
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SPE-UPLC-MS/MS测定水体中抗菌药物及代谢物方法的建立与评价
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作者 龚其龙 徐啸涛 +2 位作者 孙运超 惠杨 张苏珍 《安徽农学通报》 2026年第3期76-81,共6页
为实现水环境中抗菌药物残留的精准识别与定量分析,研究采用超高压液相色谱-串联质谱(UPLC-MS/MS)技术,结合优化的固相萃取(SPE)自动上样装置,建立了同时测定水体中磺胺类(12种)、氟喹诺酮类(8种)、酰胺醇类(4种)3类,共23种抗菌药物,及... 为实现水环境中抗菌药物残留的精准识别与定量分析,研究采用超高压液相色谱-串联质谱(UPLC-MS/MS)技术,结合优化的固相萃取(SPE)自动上样装置,建立了同时测定水体中磺胺类(12种)、氟喹诺酮类(8种)、酰胺醇类(4种)3类,共23种抗菌药物,及1种代谢产物的分析方法。试验选用沃特世Oasis HLB固相萃取柱作为富集净化材料,优化确定0.5 L为最佳上样体积;色谱分离采用Waters Acquity BEH-C18柱,以0.01%甲酸水溶液-甲醇为流动相进行梯度洗脱,流速0.3 mL/min,柱温30°C,进样量3μL;质谱采用电喷雾正离子源(ESI+)与动态多反应监测(MRM)模式,选取特征离子对进行定性定量分析,内标法校准定量结果。方法学验证结果表明,24种目标化合物在0.5~20.0 ng/mL浓度范围内线性关系良好,相关系数(R2)在0.991 1~0.999 9;方法检出限(MDLs)在0.02~1.00 ng/mL,定量限(MQLs)在0.06~3.00 ng/mL;在1.0、5.0、10.0 ng/mL 3个加标水平下,平均回收率在85.9%~113.8%,相对标准偏差(RSD)在1.7%~9.6%,准确度与精密度均符合检测要求。本研究设计的SPE自动上样装置可有效解决人工上样烦琐、精度偏低的问题,整套方法兼具高灵敏度与操作便捷性,可满足大批量水体样品中痕量抗菌药物残留的快速筛查与准确定量需求,为水环境抗生素污染监测提供参考。 展开更多
关键词 超高效液相色谱-串联质谱 固相萃取 水体 药物残留
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An accessible seismological dataset of 2021 Yangbi M_(S)6.4 earthquake
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作者 Shuguang Wang hui yang +12 位作者 Weilai Wang Fang Wang Zheng Liu Wei yang Weitao Wang Yunpeng Zhang Lu Li Jiupeng Hu Xiaobin Li Wenjian Cha Beng Ye Hongbo Zhu Jun yang 《Earthquake Science》 2021年第5期460-464,共5页
A M_(S)6.4 earthquake occurred on 21 May 2021 in Yangbi county,Dali prefecture,Yunnan,China,at 21:48 Beijing Time(13:48 UTC).Earthquakes with an M3.0 or higher occurred before and after the main shock.Seismic data ana... A M_(S)6.4 earthquake occurred on 21 May 2021 in Yangbi county,Dali prefecture,Yunnan,China,at 21:48 Beijing Time(13:48 UTC).Earthquakes with an M3.0 or higher occurred before and after the main shock.Seismic data analysis is essential for the in-depth investigation of the 2021 Yangbi M_(S)6.4 earthquake sequence and the seismotectonics of northwestern Yunnan.Institute of Geophysics,China Earthquake Administration(CEA),has compiled a dataset of seismological observations from 157 broadband stations located within 500 km of the epicenter,and has made this dataset available to the earthquake science research community.The dataset(total file size:329 GB)consists of event waveforms with a sampling frequency of 100 sps collected from 18 to 28 May 2021,20-Hz and 100-Hz continuous waveforms collected from 12 to 31 May 2021,and seismic instrument response files.To promote data sharing,the dataset also includes the seismic event waveforms from 20 to 22 May 2021 recorded at 50 stations of the ongoing Binchuan Active Source Geophysical Observation Project,for which the data protection period has not expired.Sample waveforms of the main shock are included in the appendix of this article and can be downloaded from the Earthquake Science website.The event and continuous waveforms are available from the Earthquake Science Data Center website(www.esdc.ac.cn)on application. 展开更多
关键词 Yangbi earthquake seismological dataset geophys-ical observation data share
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Microglia lactylation in relation to central nervous system diseases 被引量:2
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作者 hui yang Nan Mo +5 位作者 Le Tong Jianhong Dong Ziwei Fan Mengxian Jia Juanqing Yue Ying Wang 《Neural Regeneration Research》 SCIE CAS 2025年第1期29-40,共12页
The development of neurodegenerative diseases is closely related to the disruption of central nervous system homeostasis.Microglia,as innate immune cells,play important roles in the maintenance of central nervous syst... The development of neurodegenerative diseases is closely related to the disruption of central nervous system homeostasis.Microglia,as innate immune cells,play important roles in the maintenance of central nervous system homeostasis,injury response,and neurodegenerative diseases.Lactate has been considered a metabolic waste product,but recent studies are revealing ever more of the physiological functions of lactate.Lactylation is an important pathway in lactate function and is involved in glycolysis-related functions,macrophage polarization,neuromodulation,and angiogenesis and has also been implicated in the development of various diseases.This review provides an overview of the lactate metabolic and homeostatic regulatory processes involved in microglia lactylation,histone versus non-histone lactylation,and therapeutic approaches targeting lactate.Finally,we summarize the current research on microglia lactylation in central nervous system diseases.A deeper understanding of the metabolic regulatory mechanisms of microglia lactylation will provide more options for the treatment of central nervous system diseases. 展开更多
关键词 brain central nervous system GLYCOLYSIS immune response INFLAMMATION lactate metabolism LACTATE lactylation MICROGLIA neurodegenerative diseases
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基于三维点云的飞机扣板零件轮廓关键角点特征提取方法
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作者 惠阳 韩栋 +2 位作者 牛博雅 杨军 陈儒琛 《制造技术与机床》 北大核心 2025年第4期166-171,共6页
飞机扣板类零件的装配精度直接影响机身蒙皮的外形精度和气密性。针对扣板类零件在数字化修配测量过程中难以精准提取到关键特征的问题,提出了基于三维点云的飞机扣板零件轮廓关键角点特征提取方法。首先,对获取的三维云数据进行预处理... 飞机扣板类零件的装配精度直接影响机身蒙皮的外形精度和气密性。针对扣板类零件在数字化修配测量过程中难以精准提取到关键特征的问题,提出了基于三维点云的飞机扣板零件轮廓关键角点特征提取方法。首先,对获取的三维云数据进行预处理,得到降维后的二维点云数据;其次,分别对飞机扣板零件的扣板和互补槽采用经纬法和“凸包剔除+密度梯度筛选”法实现其装配轮廓的精准提取;再次,采用双重近邻搜索法获取装配轮廓候选角点特征;最后,基于欧式聚类方法和哈希映射方法,实现了扣板和互补槽关键角点特征的提取。试验结果表明,所提方法与现有方法比较有更好的提取效果和运行效率,且具有较好的鲁棒性,可以有效实现飞机扣板零件轮廓关键角点特征的提取。 展开更多
关键词 轮廓提取 密度梯度筛选 角点特征提取 飞机扣板 数据降维
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海城地区农居建筑抗震性能调查研究
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作者 张文静 惠杨 +2 位作者 程应伟 国艳 于浩 《防灾减灾学报》 2025年第2期50-57,共8页
为了解海城地区农居建筑抗震性能现状,采用实地抽样和无人机航拍技术相结合的方式,对海城老震区的现有农村建筑进行调查。调查结果显示:研究区域内砖混结构农居占比多达75%,其余多为砖木结构,个别农村仍有老旧土木结构房屋存量。通过对... 为了解海城地区农居建筑抗震性能现状,采用实地抽样和无人机航拍技术相结合的方式,对海城老震区的现有农村建筑进行调查。调查结果显示:研究区域内砖混结构农居占比多达75%,其余多为砖木结构,个别农村仍有老旧土木结构房屋存量。通过对典型农居建筑的结构类型、分布特征及抗震构造措施进行分析,详细梳理了不同结构类型房屋在不同地震烈度作用下的震害特点,研究成果可为震区农村建筑抗震加固及韧性提升提供决策支持。 展开更多
关键词 海城 农居建筑 抗震性能 抽样调查 构造措施
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基于数据挖掘分析何迎春治疗失眠用药规律
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作者 惠扬 黄小哲 何迎春(指导) 《新中医》 2025年第13期1-5,共5页
目的:基于数据挖掘技术分析何迎春教授治疗失眠的药物组方及用药思路。方法:收集2023年8月—2024年2月何教授在杭州市中医院门诊诊治失眠医案。运用Excel整理医案信息(包括中药频率、性味归经等),建立数据库。运用SPSS软件及Apriori算... 目的:基于数据挖掘技术分析何迎春教授治疗失眠的药物组方及用药思路。方法:收集2023年8月—2024年2月何教授在杭州市中医院门诊诊治失眠医案。运用Excel整理医案信息(包括中药频率、性味归经等),建立数据库。运用SPSS软件及Apriori算法进行数据统计分析,分析何教授治疗失眠的用药规律。结果:共纳入133首处方,整理中药147味,总频次共2279次。使用频次超过40次及以上的中药有23种,前5位是茯苓、大枣、桂枝、合欢皮、生姜。147味中药性味归经统计显示,中药药性以温、寒、平为主,药味以甘、辛、苦为主,归经以肝经、脾经、肺经、胃经、心经、肾经为主。聚类分析得到5个核心药物组合:①煅牡蛎、煅龙骨、淮小麦、黄芩、醋北柴胡、党参、炙甘草、大枣、桂枝、炒白芍;②生姜、姜半夏、茯苓、黄连、肉桂、姜竹茹、合欢皮、郁金;③煅磁石、煅珍珠母;④酸枣仁粉、灵芝;⑤桑白皮。结论:何教授治疗失眠多从肝脾论治,注重补虚泻实,调和阴阳,标本兼治。 展开更多
关键词 失眠 何迎春 数据挖掘 肝脾论治 补虚泻实 调和阴阳 标本兼治
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Beyond the tumor region:Peritumoral radiomics enhances prognostic accuracy in locally advanced rectal cancer 被引量:1
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作者 Zhi-Ying Liang Mao-Li Yu +11 位作者 hui yang Hao-Jiang Li hui Xie Chun-Yan Cui Wei-Jing Zhang Chao Luo Pei-Qiang Cai Xiao-Feng Lin Kun-Feng Liu Lang Xiong Li-Zhi Liu Bi-Yun Chen 《World Journal of Gastroenterology》 2025年第8期49-65,共17页
BACKGROUND The peritumoral region possesses attributes that promote cancer growth and progression.However,the potential prognostic biomarkers in this region remain relatively underexplored in radiomics.AIM To investig... BACKGROUND The peritumoral region possesses attributes that promote cancer growth and progression.However,the potential prognostic biomarkers in this region remain relatively underexplored in radiomics.AIM To investigate the prognostic value and importance of peritumoral radiomics in locally advanced rectal cancer(LARC).METHODS This retrospective study included 409 patients with biopsy-confirmed LARC treated with neoadjuvant chemoradiotherapy and surgically.Patients were divided into training(n=273)and validation(n=136)sets.Based on intratumoral and peritumoral radiomic features extracted from pretreatment axial high-resolution small-field-of-view T2-weighted images,multivariate Cox models for progression-free survival(PFS)prediction were developed with or without clinicoradiological features and evaluated with Harrell’s concordance index(C-index),calibration curve,and decision curve analyses.Risk stratification,Kaplan-Meier analysis,and permutation feature importance analysis were performed.RESULTS The comprehensive integrated clinical-radiological-omics model(ModelICRO)integrating seven peritumoral,three intratumoral,and four clinicoradiological features achieved the highest C-indices(0.836 and 0.801 in the training and validation sets,respectively).This model showed robust calibration and better clinical net benefits,effectively distinguished high-risk from low-risk patients(PFS:97.2%vs 67.6%and 95.4%vs 64.8%in the training and validation sets,respectively;both P<0.001).Three most influential predictors in the comprehensive ModelICRO were,in order,a peritumoral,an intratumoral,and a clinicoradiological feature.Notably,the peritumoral model outperformed the intratumoral model(C-index:0.754 vs 0.670;P=0.015);peritumoral features significantly enhanced the performance of models based on clinicoradiological or intratumoral features or their combinations.CONCLUSION Peritumoral radiomics holds greater prognostic value than intratumoral radiomics for predicting PFS in LARC.The comprehensive model may serve as a reliable tool for better stratification and management postoperatively. 展开更多
关键词 Rectal cancer Peritumoral radiomics Intratumoral radiomics Prognosis analysis Variable importance analysis Tumor microenvironment
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Synergistic Molecular Engineering Strategies for Enhancing Diffusion Kinetics and Interfacial Stability of theδ-MnO_(2)Cathode in Aqueous Zinc-Ion Batteries 被引量:1
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作者 Yaxi Ding Keming Zhu +10 位作者 Haoqu Jin Wenxia Gao Bing Wang Shi Bian Rui He Jiahong Wang hui yang Kramer Denis Xue-Feng Yu Chunyi Zhi Chao Peng 《Carbon Energy》 2025年第8期15-25,共11页
Layered manganese dioxide(δ-MnO_(2))is a promising cathode material for aqueous zinc-ion batteries(AZIBs)due to its high theoretical capacity,high operating voltage,and low cost.However,its practical application face... Layered manganese dioxide(δ-MnO_(2))is a promising cathode material for aqueous zinc-ion batteries(AZIBs)due to its high theoretical capacity,high operating voltage,and low cost.However,its practical application faces challenges,such as low electronic conductivity,sluggish diffusion kinetics,and severe dissolution of Mn^(2+).In this study,we developed a δ-MnO_(2) coated with a 2-methylimidazole(δ-MnO_(2)@2-ML)hybrid cathode.Density functional theory(DFT)calculations indicate that 2-ML can be integrated into δ-MnO_(2) through both pre-intercalation and surface coating,with thermodynamically favorable outcomes.This modification expands the interlayer spacing of δ-MnO_(2) and generates Mn-N bonds on the surface,enhancing Zn^(2+)accommodation and diffusion kinetics as well as stabilizing surface Mn sites.The experimentally prepared δ-MnO_(2)@2-ML cathode,as predicted by DFT,features both 2-ML pre-intercalation and surface coating,providing more zinc-ion insertion sites and improved structural stability.Furthermore,X-ray diffraction shows the expanded interlayer spacing,which effectively buffers local electrostatic interactions,leading to an enhanced Zn^(2+)diffusion rate.Consequently,the optimized cathode(δ-MnO_(2)@2-ML)presents improved electrochemical performance and stability,and the fabricated AZIBs exhibit a high specific capacity(309.5mAh/g at 0.1 A/g),superior multiplicative performance(137.6mAh/g at 1 A/g),and impressive capacity retention(80%after 1350 cycles at 1 A/g).These results surpass the performance of most manganese-based and vanadium-based cathode materials reported to date.This dual-modulation strategy,combining interlayer engineering and interface optimization,offers a straightforward and scalable approach,potentially advancing the commercial viability of low-cost,high-performance AZIBs. 展开更多
关键词 2-METHYLIMIDAZOLE manganese oxide Mn dissolution pre-intercalation surface coating
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Vascularized organoid-on-a-chip for centimeter-scale organoid cultivation 被引量:1
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作者 Xiaofeng Gong Chen yang +5 位作者 Jianchen Peng Xiao Ding hui yang Aaron Gerald Wang Emmanuel Enoch Dzakah Bing Zhao 《Bio-Design and Manufacturing》 2025年第3期410-422,I0023-I0027,共18页
An organoid is a three-dimensional(3D)cell culture model that can reproduce the distinct structure and inherent functionality of certain organs.Nevertheless,a major limitation of organoids is the absence of a complex ... An organoid is a three-dimensional(3D)cell culture model that can reproduce the distinct structure and inherent functionality of certain organs.Nevertheless,a major limitation of organoids is the absence of a complex vascular network,thus restricting the supply of oxygen and essential nutrients.Coupled with their inherent size constraints and metabolite accumulation,it is challenging for organoids to replicate the natural intricacies of organs,thereby limiting their applicability.To overcome the challenges associated with this technology,we developed a culture platform to cultivate tumors or organ-derived organoids up to the centimeter scale.Initially,a customized organoid-on-a-chip including a microvascular network at the micron scale was designed using 3D printing.Further,by integrating an infusion device,the chip ensures an adequate supply of nutrients and fluid immersion while mimicking blood flow dynamics.Our method overcomes the issue of the limited size of organoids due to insufficient nutrient access,making it possible to produce large-scale tumor and normal tissue models in vitro,while providing insights into drug efficacy and toxicology evaluation as well as standardized organoid production. 展开更多
关键词 Organoid Tumoroid BIOMATERIALS Organoid-on-a-chip Biomedical engineering
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Vertical channels enable excellent lithium storage kinetics and cycling stability in silicon/carbon thick electrode 被引量:1
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作者 Wen Zhang Zihan Zhang +13 位作者 Xinxin Wang Wanming Li Qin Chen Wangting Zhong Junhong Wei Zihe Chen Shuibin Tu Xiancheng Wang Yuchen Tan Yun Zhang huiqiao Li Yongming Sun Huamin Zhou hui yang 《Carbon Energy》 2025年第2期54-65,共12页
Constructing silicon(Si)-based composite electrodes that possess high energy density,long cycle life,and fast charging capability simultaneously is critical for the development of high performance lithium-ion batterie... Constructing silicon(Si)-based composite electrodes that possess high energy density,long cycle life,and fast charging capability simultaneously is critical for the development of high performance lithium-ion batteries for mitigating range anxiety and slow charging issues in new energy vehicles.Herein,a thick silicon/carbon composite electrode with vertically aligned channels in the thickness direction(VC-SC)is constructed by employing a bubble formation method.Both experimental characterizations and theoretical simulations confirm that the obtained vertical channel structure can effectively address the problem of sluggish ion transport caused by high tortuosity in conventional thick electrodes,conspicuously enhance reaction kinetics,reduce polarization and side reactions,mitigate stress,increase the utilization of active materials,and promote cycling stability of the thick electrode.Consequently,when paired with LiNi_(0.6)Co_(0.2)Mn_(0.2)O_(2)(NCM622),the VC-SC||NCM622 pouch type full cell(~6.0 mAh cm^(-2))exhibits significantly improved rate performance and capacity retention compared with the SC||NCM622 full cell with the conventional silicon/carbon composite electrode without channels(SC)as the anode.The assembled VC-SC||NCM622 pouch full cell with a high energy density of 490.3 Wh kg^(-1)also reveals a remarkable fast charging capability at a high current density of 2.0 mA cm^(-2),with a capacity retention of 72.0%after 500 cycles. 展开更多
关键词 high transport kinetics silicon/carbon anode structural stability thick electrode vertical channels
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基于近场辐射的干涉仪校准方案
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作者 曾元祁 罗德巳 +4 位作者 徐利兵 惠洋 盛涛 赵国栋 熊关生 《电子信息对抗技术》 2025年第4期73-79,共7页
干涉仪测向技术具有宽频段、高精度和性价比高等优点,在无源测向定位领域具有广泛应用。通过分析干涉仪测向系统相位误差组成,提出了基于近场辐射的干涉仪校准方案。利用干涉仪单元天线和天线罩之间的电磁波反射特性构建稳定的近场空间... 干涉仪测向技术具有宽频段、高精度和性价比高等优点,在无源测向定位领域具有广泛应用。通过分析干涉仪测向系统相位误差组成,提出了基于近场辐射的干涉仪校准方案。利用干涉仪单元天线和天线罩之间的电磁波反射特性构建稳定的近场空间,获得单元天线间的近场校准值,继而间接得到干涉仪测向所需的多通道间相位差校准值,以满足系统测向需求,实现干涉仪外场免外辐射校准。构建了测试场景验证了该方案的可行性和有效性,为干涉仪校准探索了一种新的途径。 展开更多
关键词 干涉仪测向 通道校准 远场辐射 近场辐射
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基于加速度的机器人铣削力快速辨识方法
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作者 田维军 惠阳 +3 位作者 薛莹 杨选宏 史江海 侯马骁 《制造技术与机床》 北大核心 2025年第6期20-25,共6页
机器人铣削过程中的铣削力可以用于监测工件加工质量、刀具状态等,是最重要的参数之一。然而,在大型结构件加工中,很难通过测力仪直接测量机器人铣削力。文章提出一种基于加速度的机器人铣削力快速辨识方法。首先,根据机器人系统中加速... 机器人铣削过程中的铣削力可以用于监测工件加工质量、刀具状态等,是最重要的参数之一。然而,在大型结构件加工中,很难通过测力仪直接测量机器人铣削力。文章提出一种基于加速度的机器人铣削力快速辨识方法。首先,根据机器人系统中加速度与铣削力之间的关系,构建加速度间接辨识机器人铣削力框架。然后,基于机器人系统矩阵的递推性和正则化算子的特殊性,提升机器人铣削力辨识的速度。最后,通过机器人铣削试验验证了所提方法的有效性。试验结果表明,所提机器人铣削力快速辨识方法将辨识时间缩短到15 ms以内。 展开更多
关键词 轮廓线提取 密度梯度筛选 角点特征提取 飞机扣板 数据降维
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基于优化PSO-BP算法的耦合时空特征下地铁客流预测 被引量:35
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作者 惠阳 王永岗 +2 位作者 彭辉 侯淑倩 余强(指导) 《交通运输工程学报》 EI CSCD 北大核心 2021年第4期210-222,共13页
为提高地铁客流预测的准确性,以西安地铁1号线为例,分析了地铁客流的耦合时空特征,提取了影响地铁客流变化的5个主要因素,包括节日、非节日、时间段、站点和天气,构建了反向传播(BP)神经网络,预测了地铁客流;利用引入自适应变异与均衡... 为提高地铁客流预测的准确性,以西安地铁1号线为例,分析了地铁客流的耦合时空特征,提取了影响地铁客流变化的5个主要因素,包括节日、非节日、时间段、站点和天气,构建了反向传播(BP)神经网络,预测了地铁客流;利用引入自适应变异与均衡惯性权重的粒子群优化(PSO)算法,优化了BP神经网络,形成了考虑复杂因素影响的地铁客流预测系统;选取了换乘站、非换乘站的首站与中间站,引入天气、节日、非节日因素,对比了不同时间段下的BP神经网络模型,优化了PSO-BP神经网络模型的预测误差。研究结果表明:考虑天气、节日、非节日因素,换乘站点分时段优化PSO-BP神经网络模型预测的平均绝对误差、均方根误差和平均绝对百分比误差,较不分时段的优化PSO-BP神经网络模型分别平均下降了40.13%、31.46%和23.89%,较分时段的BP神经网络模型分别平均下降了17.50%、17.86%和17.32%;非换乘站点分时段优化PSO-BP神经网络模型预测的平均绝对误差、均方根误差和平均绝对百分比误差,较不分时段的优化PSO-BP神经网络模型分别平均下降了16.50%、20.99%和32.59%,较分时段的BP神经网络模型分别平均下降了11.48%、12.10%和17.73%;各站点分时段优化PSO-BP神经网络模型预测的平均绝对误差、均方根误差、平均绝对百分比误差,较不分时段的优化PSO-BP神经网络模型分别平均下降了24.37%、24.48%和29.69%,较分时段的BP神经网络模型分别平均下降了13.49%、14.02%和17.59%,因此,利用考虑多影响因素的优化PSO-BP神经网络模型能提高地铁客流预测的准确性。 展开更多
关键词 城市轨道交通 客流预测 耦合时空特征 反向传播神经网络 粒子群优化算法 自适应变异 惯性权重
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天然橡胶的老化机理 被引量:29
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作者 丁玲 李志辉 +4 位作者 杨慧 王相鹏 梁梨花 钟建永 邹友思 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2018年第5期76-83,共8页
采用人工紫外光老化和自然老化2种方法对天然橡胶(NR)进行老化研究,利用傅里叶变换红外光谱、核磁共振波谱及紫外-可见光吸收光谱测试法对老化产物进行表征,探究了NR的老化机理。结果表明,天然橡胶抗紫外光老化能力较差,在紫外光下照射3... 采用人工紫外光老化和自然老化2种方法对天然橡胶(NR)进行老化研究,利用傅里叶变换红外光谱、核磁共振波谱及紫外-可见光吸收光谱测试法对老化产物进行表征,探究了NR的老化机理。结果表明,天然橡胶抗紫外光老化能力较差,在紫外光下照射3 h,其分子结构即发生明显改变,而在自然老化的条件下,天然橡胶经过30 d结构才发生变化。天然橡胶的老化机理:双键α-H最先被活化,随后发生氧化生成醛酮等氧化产物,同时双键被加成,烯氢含量减少;老化过程中,氧化降解与交联反应同时存在,老化前期以降解为主,后期产生交联。以核磁谱图为依据对烯氢的氧化百分比进行定量分析,建立了本实验条件下2种老化方程,并得出了自然老化时间与人工紫外光老化时间的关系,天然橡胶经紫外光老化7 d约相当于自然老化下3个月的老化效果。 展开更多
关键词 天然橡胶 紫外光老化 自然老化 老化机理
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转移性鼻咽癌一线化疗后替吉奥维持治疗的多中心随机对照研究 被引量:6
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作者 杨慧 陆颖 +4 位作者 黄海欣 胡晓桦 黄昌杰 刘美莲 冯献斌 《中国肿瘤临床》 CAS CSCD 北大核心 2021年第1期25-29,共5页
目的:探讨转移性鼻咽癌一线化疗后替吉奥(S-1)维持治疗的有效性、安全性及获益的分子标志物,为延长转移性鼻咽癌患者无进展生存期(progression-free survival,PFS)提供新选择。方法:选取2016年1月至2019年5月就诊于广西医科大学第四附... 目的:探讨转移性鼻咽癌一线化疗后替吉奥(S-1)维持治疗的有效性、安全性及获益的分子标志物,为延长转移性鼻咽癌患者无进展生存期(progression-free survival,PFS)提供新选择。方法:选取2016年1月至2019年5月就诊于广西医科大学第四附属医院、广西医科大学第一附属医院、南宁市第二人民医院、桂林医学院附属医院、柳州市中医医院的一线化疗(CT)临床获益的转移性鼻咽癌患者,依照1:1分层随机分为替吉奥维持治疗组(CT+S1)和观察组(CT),评价维持治疗的安全性及PFS获益。分析血浆EB病毒DNA(EBV-DNA)及血清淀粉样蛋白A(SAA)治疗后变化与维持治疗获益的相关性。结果:本研究入组203例患者,中位随访时间19.8(6.1~51.3)个月,经一线化疗临床获益的可评价病例183例,其中CT+S1组88例,CT组95例。与CT组比较,CT+S1组患者的中位PFS(median PFS,mPFS)显著延长(16.2个月vs.8.7个月,P<0.001)。CT组中位替吉奥干预14(4~58)个疗程,主要不良反应为1级皮肤色素沉着、口腔黏膜炎、手足综合征、恶心等,经方案调整或短期治疗延迟(<2周)患者均可耐受。入组患者EBV-DNA、SAA监测提示,一线化疗后EBV-DNA未下降至0或SAA仍有持续下降的患者可以从后续干预治疗中获益,48.5%(32/66)的患者在后续的干预治疗中出现上述指标的持续下降。仍有可评价病灶的51.2%(44/86)患者出现病灶的进一步缓解。结论:一线化疗后的替吉奥维持治疗可改善转移性鼻咽癌患者的PFS,通过合理的用药方案调整,患者耐受性良好。血浆EBV-DNA、SAA持续下降、影像学残留的患者可能从维持治疗中获得更为显著的临床获益。 展开更多
关键词 转移性鼻咽癌 一线化疗 替吉奥 维持治疗 预后因素
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