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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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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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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:34
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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:28
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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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地铁站应急疏散效率影响因素分析及优化策略 被引量:6
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作者 惠阳 余强 +1 位作者 王永岗 彭辉 《长安大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第4期130-138,共9页
为了提高地铁站突发事件发生时人员的应急疏散效率,通过深入分析搭建影响疏散效率的因素模型,并对各因素对应急疏散的影响进行综合评估。以西安市五路口地铁站为研究对象,运用Pathfinder仿真软件建立了应急疏散仿真模型,以此为基础构建... 为了提高地铁站突发事件发生时人员的应急疏散效率,通过深入分析搭建影响疏散效率的因素模型,并对各因素对应急疏散的影响进行综合评估。以西安市五路口地铁站为研究对象,运用Pathfinder仿真软件建立了应急疏散仿真模型,以此为基础构建了包括客流特征、设施布局、列车运行和人员特征等一级指标评价模型。在评价模型的构建过程中,采用了算术平均值法、几何平均值法和特征值法进行权重求解,对影响因素的权重进行了全面分析,以准确识别出不同指标下关键应急疏散因子的权重。基于对地铁应急疏散影响因素分析,提出了一系列针对性的优化建议。研究结果表明:高峰列车通行数量、闸机的通行能力、楼梯的通行能力、列车的承载能力、人员的行为特征和扶梯的通行能力等6个因素对地铁应急疏散能力具有重要影响,综合权重占比约为85%,这些因素对地铁站的安全运营具有重要意义。研究结果对地铁站的安全性评价和紧急疏散能力提升具有重要意义,可为地铁运营管理部门提供科学依据和指导。 展开更多
关键词 交通工程 地铁站 应急疏散效率 层次分析法 PATHFINDER 因子权重比
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电磁轨道材料表面损伤及强化技术研究现状 被引量:17
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作者 闫涛 刘贵民 +2 位作者 朱硕 杜林飞 惠阳 《材料导报》 EI CAS CSCD 北大核心 2018年第1期135-140,148,共7页
轨道材料的性能是决定电磁轨道炮工程应用的关键因素。在大载流、高温的苛刻工况下,表面刨削、转捩和电弧烧蚀以及载流摩擦磨损是电磁轨道表面的主要损伤形式。综述了电磁炮轨道刨削现象及其产生原因和微观机理的研究现状,总结了转捩和... 轨道材料的性能是决定电磁轨道炮工程应用的关键因素。在大载流、高温的苛刻工况下,表面刨削、转捩和电弧烧蚀以及载流摩擦磨损是电磁轨道表面的主要损伤形式。综述了电磁炮轨道刨削现象及其产生原因和微观机理的研究现状,总结了转捩和电弧烧蚀对轨道性能的影响,概括了电磁轨道炮中载流摩擦磨损的特点,为开发新型轨道材料提供依据和借鉴。 展开更多
关键词 电磁轨道 轨道材料 表面损伤
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方形截面纤维表面气溶胶粒子多机理过滤性能数值分析 被引量:6
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作者 杨会 朱辉 +1 位作者 陈永平 付海明 《过程工程学报》 CAS CSCD 北大核心 2020年第4期400-409,共10页
采用数值方法求解绕方形截面纤维流场,考虑粒子布朗扩散、拦截效应和惯性碰撞捕集机理的联合作用,用布朗动力学方法研究方形截面纤维的过滤性能,考察了纤维迎风角(θ)、填充率(C)和过滤风速(u_∞)对捕集效率、质量因子及粒子沉积分布的... 采用数值方法求解绕方形截面纤维流场,考虑粒子布朗扩散、拦截效应和惯性碰撞捕集机理的联合作用,用布朗动力学方法研究方形截面纤维的过滤性能,考察了纤维迎风角(θ)、填充率(C)和过滤风速(u_∞)对捕集效率、质量因子及粒子沉积分布的影响。结果表明,小粒子的扩散捕集或大粒子的惯性捕集在方形纤维表面的粒子沉积行为均表现出显著的局部沉积特征,且与粒子捕集机理和迎风角有关。方形纤维质量因子的分析结果表明,在高填充率下,方形纤维的过滤压降虽高于圆截面纤维,但具有较高的捕集效率,综合过滤性能仍明显优于圆截面纤维,但在低填充率下,方形纤维综合过滤性能劣于圆截面纤维。 展开更多
关键词 空气过滤 方形纤维 多机理 质量因子 数值方法
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Research hotspot and trend of plant water use in karst: Based on a bibliometric analysis from 1984 to 2022
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作者 De-gen Zhu Jing Ning +5 位作者 hui yang Jun-bing Pu Jian-hua Cao Meng-xia Zhou Mitja Prelovsek Natasa Ravbar 《China Geology》 2025年第1期214-229,共16页
Research on the ecohydrological processes of terrestrial plants is a frontier field comprising ecology,hydrology and global change research,yielding the key theoretical foundations of ecohydrology.In karst areas,due t... Research on the ecohydrological processes of terrestrial plants is a frontier field comprising ecology,hydrology and global change research,yielding the key theoretical foundations of ecohydrology.In karst areas,due to its unique geological background,the karst landscape is strongly developed,with high bedrock exposure,high permeability,fragmented soils,shallow soils,and high spatial heterogeneity,resulting in very limited water storage for plant uptake and growth in rock fissures and shallow soils.Therefore,water conditions are an important ecological factor influencing plant growth.To comprehensively understand the current progress and development trends in plant water use research focusing on karst areas,this paper uses the VOSviewer software to analyze the literature on plant water use in karst areas between 1984 and 2022.The results showed that:(1)Research on plant water use in karst areas has developed rapidly worldwide,and the number of relevant studies in the literature have increased year by year,which together means that it is attracting more and more attention.(2)The investigation of plant water sources,geological background of karst areas,seasonal arid tropical climates,the relationship betweenδ13C values and plant water use efficiency,karst plant water use in karst savannas and subtropical areas,and ecosystems under climate change yields the knowledge base in this field.(3)Most studies in this area focus on the division of water sources of plants in karst areas,the methods of studying the water use sources of plants,and the water use strategies and efficiency of plants.(4)Future research will focus on how plant water use in karst areas is influenced by Earth’s critical zones,climate change,and ecohydrological separation.These studies will provide a key scientific basis for guiding ecological restoration and promoting sustainable development in karst areas. 展开更多
关键词 Terrestrial plants Plant water use Karst area Climate change ECOHYDROLOGY BIBLIOMETRICS Ecological restoration Sustainable development Environmental restoration engineering Web of Science
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Clinical Application of Positron Emission Tomography/Magnetic Resonance Imaging in Pelvic Malignant Tumors
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作者 hui yang Jielin Bai +5 位作者 Xuena Li Yaming Li Bulin Du Yan Cui Shu Wang Yuxiang Wang 《iRADIOLOGY》 2025年第6期421-433,共13页
Positron emission tomography/magnetic resonance imaging(PET/MRI)combines the advantages of both imaging modalities.PET/MRI demonstrates superior performance in the evaluation of the therapeutic impact,staging,diagnosi... Positron emission tomography/magnetic resonance imaging(PET/MRI)combines the advantages of both imaging modalities.PET/MRI demonstrates superior performance in the evaluation of the therapeutic impact,staging,diagnosis,and treatment planning of malignancies because of its lower radiation dose,higher contrast for soft tissues,and multiparametric functional imaging.^(18)F-fluorodeoxyglucose PET/MRI has demonstrated considerable potential in the assessment of pelvic malignancies.This review briefly describes the evolution of PET/MRI imaging technology and compares the application of PET/MRI in five common pelvic tumors,including endometrial cancer,cervical cancer,ovarian cancer,prostate cancer,and bladder cancer,with that of PET/computed tomography.Additionally,radiotracers other than^(18)F-fluorodeoxyglucose have been introduced for use in pelvic tumors.The development and application of these new tracers further enhance the clinical application of PET/MRI in precision medicine for pelvic malignant cancers.Overall,this review revealed the unique contribution of PET/MRI as a promising diagnostic instrument in the management of pelvic tumors,demonstrating its important position in future clinical practice. 展开更多
关键词 bladder cancer cervical cancer clinical application comparative study endometrial cancer ovarian cancer positron emission tomography/computed tomography positron emission tomography/magnetic resonance imaging prostate cancer
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GaN-based blue laser diodes with output power of 5 W and lifetime over 20000 h aged at 60℃
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作者 Lei Hu Siyi Huang +6 位作者 Zhi Liu Tengfeng Duan Si Wu Dan Wang hui yang Jun Wang Jianping Liu 《Journal of Semiconductors》 2025年第4期9-11,共3页
Stimulated emission and lasing of GaN-based laser diodes(LDs)were reported at 1995[1]and 1996[2],right after the breakthrough of p-type doping[3−5],material quality[6]and the invention of high-brightness GaN-based LED... Stimulated emission and lasing of GaN-based laser diodes(LDs)were reported at 1995[1]and 1996[2],right after the breakthrough of p-type doping[3−5],material quality[6]and the invention of high-brightness GaN-based LEDs[7,8].However,it took much longer time for GaN-based LDs to achieve high power,high wall plug efficiency,and long lifetime.Until 2019,Nichia reported blue LDs with these performances[9],which open wide applications with GaN-based blue LDs. 展开更多
关键词 Blue laser diodes P type doping LIFETIME Output power Stimulated emission GAN based laser diodes stimulated emission lasing laser diodes lds
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