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A novel long persistent luminescent material CaGeO_(3):Tb^(3+)with photo-stimulation properties 被引量:1
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作者 Wei Meng Xiaoyan Fu +7 位作者 Tongyan Lin Zewen Liu Naihui chen Jiaxu Zhang Runyao Liu Rujun Yang long chen Hongwu Zhang 《Journal of Rare Earths》 SCIE EI CAS CSCD 2024年第7期1233-1239,I0002,共8页
A novel green long afterglow material CaGeO_(3):Tb^(3+)was synthesized by high temperature solid phase method.According to the experimental results,CaGeO_(3):Tb^(3+)is a green long persistent luminescent(LPL)material ... A novel green long afterglow material CaGeO_(3):Tb^(3+)was synthesized by high temperature solid phase method.According to the experimental results,CaGeO_(3):Tb^(3+)is a green long persistent luminescent(LPL)material with excellent performance.CaGeO_(3):Tb^(3+)shows LPL emission peak at 442,490.9,548.7,588.5 and 623.8 nm,corresponding to ^(5)D_(3) to^(7)F_(4)and^(5)D_(4)to^(7)F_(J)(J=6,5,4,3)transitions of Tb^(3+).Its CIE coordinates are(0.27,0.50),indicating that the afterglow emission is close to the light of green region.In addition,after the excitation source is turned off,the afterglow time is longer than 90 min.After an interval of 7 h,the photo-stimulation luminescence(PSL)can be observed by using 980 nm laser cyclic excitation.The thermoluminescence(ThL)results show that there are three types of traps in the material and their depths are 0.666,0.774 and 0.892 eV respectively,which are caused by the doping of Tb^(3+).All the results show that CaGeO_(3):Tb^(3+)is an excellent long afterglow luminescent material. 展开更多
关键词 Long persistent luminescence Photo-stimulation TRAP CaGeO_(3):Tb^(3+) Rare earths
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Prolonged SARS-CoV-2 Viral Shedding in Patients with COVID-19 was Associated with Delayed Initiation of Arbidol Treatment and Consulting Doctor Later: A Retrospective Cohort Study
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作者 Xin-liang HE Ya-ya ZHOU +8 位作者 Wei FU Yu-e XUE Meng-yuan LIANG Bo-han YANG Wan-li MA Qiong ZHOU long chen Jian-chu ZHANG Xiao-rong WANG 《Current Medical Science》 SCIE CAS 2021年第6期1096-1104,共9页
Objective:To study data about SARS-CoV-2 virus shedding and clarify the risk factors for prolonged virus shedding.Methods:Data were retrospectively collected from adults hospitalized with laboratory-confirmed coronavi... Objective:To study data about SARS-CoV-2 virus shedding and clarify the risk factors for prolonged virus shedding.Methods:Data were retrospectively collected from adults hospitalized with laboratory-confirmed coronavirus disease-19(COVID-19)in Wuhan Union Hospital.We compared clinical features among patients with prolonged(a positive SARS-CoV-2 RNA on day 23 after illness onset)and short virus shedding and evaluated risk factors associated with prolonged virus shedding by multivariate regression analysis.Results:Among 238 patients,the median age was 55.5 years,57.1%were female,92.9%(221/238)were administered with arbidol,58.4%(139/238)were given arbidol in combination with interferon.The median duration of SARS-CoV-2 virus shedding was 23 days(IQR,17.8-30 days)with a longest one of 51 days.The patients with prolonged virus shedding had higher value of D-dimer(P=0.002),IL-6(P<0.001),CRP(P=0.005)and more lobes lung lesion(P=0.014)on admission,as well as older age(P=0.017)and more patients with hypertension(P=0.044)than in those the virus shedding less than 23 days.Multivariate regression analysis revealed that prolonged viral shedding was significantly associated with initiation arbidol≥8 days after symptom onset[OR:2.447,95%CI(1.351-4.431)],≥3 days from onset of symptoms to first medical visitation[OR:1.880,95%CI(1.035-3.416)],illness onset before Jan.31,2020[OR:3.289,95%CI(1.474-7.337)].Arbidol in combination with interferon was also significantly associated with shorter virus shedding[OR:0.363,95%CI(0.191-0.690)].Conclusion:Duration of SARS-CoV-2 virus shedding was long.Early initiation of arbidol and arbidol in combination with interferon as well as consulting doctor timely after illness onset were helpful for SARS-CoV-2 clearance. 展开更多
关键词 SARS-CoV-2 viral shedding risk factors antiviral treatment ARBIDOL
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基于二胺配体的钛配合物催化乙烯共聚合研究 被引量:1
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作者 杨明萱 郭新星 +3 位作者 陈龙 孙俊芬 李明远 蔡正国 《高分子学报》 北大核心 2025年第10期1791-1800,共10页
合成了两种基于二胺配体的六元环非茂钛配合物[RN(CH_(2))_(3)NR]TiMe_(2)(4a:R=2,6-Me_(2)-C_(6)H_(3), 4b:R=2,6-iPr_(2)-C_(6)H_(3))并进行了结构表征,随后在改性甲基铝氧烷(MMAO)活化下,系统研究了其催化乙烯均聚及共聚行为.实验结... 合成了两种基于二胺配体的六元环非茂钛配合物[RN(CH_(2))_(3)NR]TiMe_(2)(4a:R=2,6-Me_(2)-C_(6)H_(3), 4b:R=2,6-iPr_(2)-C_(6)H_(3))并进行了结构表征,随后在改性甲基铝氧烷(MMAO)活化下,系统研究了其催化乙烯均聚及共聚行为.实验结果表明,配体芳环上带有异丙基的配合物4b比带有甲基的配合物4a表现出更高的聚合活性.在Al/Ti摩尔比为800、聚合温度为100℃、乙烯压力为2.0 MPa的条件下,4b催化乙烯均聚的活性高达1.68×10^(6) g·mol^(-)1·h^(-1),并且在催化乙烯与1-癸烯共聚中表现出更高活性,达到4.08×10^(6) g·mol^(-)1·h^(-1).该类催化体系在145℃的聚合温度下仍保持稳定的聚合活性,说明其具有优异的热稳定性.本研究揭示了二胺类钛催化剂配体芳环上取代基的电子位阻效应对催化性能的影响机制,对设计开发兼具高活性、高耐温性及优异共聚能力的非茂钛催化剂体系具有重要意义. 展开更多
关键词 二胺钛配合物 乙烯 Α-烯烃 共聚
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表面粗糙化聚甲醛/聚丙烯共混纤维的制备与性能 被引量:2
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作者 杨汪洋 杨新华 +2 位作者 刘园园 陈龙 孙俊芬 《高分子材料科学与工程》 北大核心 2025年第1期53-60,共8页
文中采用熔融共混法制备了不同聚甲醛(POM)含量(5%,10%和15%)的聚甲醛/聚丙烯(PP)共混物,并使用“熔纺-拉伸”两步法制备了POM/PP共混纤维,使用旋转流变仪、扫描电镜、纤维拉力仪等分析手段研究了POM含量对POM/PP共混物流变性能以及对... 文中采用熔融共混法制备了不同聚甲醛(POM)含量(5%,10%和15%)的聚甲醛/聚丙烯(PP)共混物,并使用“熔纺-拉伸”两步法制备了POM/PP共混纤维,使用旋转流变仪、扫描电镜、纤维拉力仪等分析手段研究了POM含量对POM/PP共混物流变性能以及对共混纤维表面形貌、力学性能及基体结合性能的影响。结果表明,POM的加入改善了共混物的熔体加工性能与热稳定性以及纤维的表面粗糙度、抗蠕变性能与基体结合性能。当POM质量分数为10%时,纤维的断裂强度达到3.32 cN/dtex,在环氧树脂中的基体结合强度为68.9 kPa,是性能良好的增强材料。 展开更多
关键词 聚丙烯纤维 聚甲醛 纤维增强复合材料 流变性能 基体结合性能
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直流开断工况下金属氧化压敏电阻冲击老化及失效特性研究
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作者 龙辰 白云帆 +3 位作者 吴益飞 吴翊 纽春萍 荣命哲 《西安交通大学学报》 北大核心 2025年第9期53-64,共12页
为了探究直流开断过程中金属氧化物压敏电阻(MOV)的老化及失效特性,搭建了MOV老化失效实验平台,研究了在重复脉冲作用下,MOV的阈值电压、泄漏电流、非线性系数以及残压的变化规律。研究发现,阈值电压U_(1mA)随冲击次数增多先上升后下降... 为了探究直流开断过程中金属氧化物压敏电阻(MOV)的老化及失效特性,搭建了MOV老化失效实验平台,研究了在重复脉冲作用下,MOV的阈值电压、泄漏电流、非线性系数以及残压的变化规律。研究发现,阈值电压U_(1mA)随冲击次数增多先上升后下降,整体变化不超过1%,泄漏电流I_(75%)随冲击次数增加接近线性增长,而非线性系数α随冲击次数增加逐步减小,且下降速度与冲击能量正相关,残压U_(res)变化小于5%。采用泄漏电流作为标准可以更直观地反映MOV的老化情况。通过分析不同能量下多次冲击后的MOV失效情况,建立了冲击能量与失效统计次数N_(50%)之间的关系。利用有限元仿真,建立了MOV失效模型,研究了微观晶粒中电流、温度及应力的分布规律以及失效阈值,并通过实验验证了失效模型的准确性。结果表明,模型在失效阈值预测方面的误差为8%,在各种能量冲击下的温度预测方面的误差均小于5%。 展开更多
关键词 金属氧化物压敏电阻 老化 失效 直流开断
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林区道路网络消防功能评价
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作者 龙晨 庞燕 +1 位作者 王擎天 王忠伟 《中南林业科技大学学报》 北大核心 2025年第8期196-206,共11页
【目的】为适应森林防灭火工作的需求,构建林道网消防功能评价方法,表征林道网消防能力空间布局,探究消防功能薄弱区域并提出改善建议,从而保障森林的可持续经营和多功能发展。【方法】基于地理信息系统(GIS)技术、多准则决策(MCDM)方法... 【目的】为适应森林防灭火工作的需求,构建林道网消防功能评价方法,表征林道网消防能力空间布局,探究消防功能薄弱区域并提出改善建议,从而保障森林的可持续经营和多功能发展。【方法】基于地理信息系统(GIS)技术、多准则决策(MCDM)方法,从技术、经济、环境维度,筛选出芦头实验林场道路线密度、高核密度区域占比、道路覆盖度、水源可达性、消防设施2 km服务区内道路占比、里程收益额、里程成本费用、途经坡度不适宜建设区占比、途经地形起伏度不适宜建设区占比、途经NDVI不适宜建设区占比10个评价指标。采用层次分析法(AHP)和熵权法(EWM)确定评价指标的主观及客观权重,基于加权平均法确定指标的综合权重,以指标区间赋值与权重为基础,构建林区道路网络消防能力评价模型。【结果】林区道路网络整体的消防功能评价结果为优秀,特别是消防可达性和水源可达性表现突出,确保大部分区域能够在火灾发生时迅速获得救援。但林场的西南部和北部区域存在消防覆盖度不足的现象,需要进行林道网针对性提质升级。【结论】从多维度构建林道网消防功能评价指标体系及模型,可为评价林区消防响应能力提供理论支撑,为林道网提质升级提供系统的科学依据。 展开更多
关键词 林道网 森林防火 道路评价 GIS 国有林场
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基于多光谱遥感影像的城市树木地上生物量反演方法
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作者 童珮灵 林聪 +4 位作者 朱宁宁 陈喆 龙宸 董震 杨必胜 《测绘地理信息》 2025年第4期100-105,共6页
城市树木作为城市绿地的主要组成部分,承担着多项重要生态功能,其地上生物量反映了城市生态系统的碳储存能力和生态健康水平。面对传统地上生物量测定方法在复杂城市环境下的诸多限制,本研究基于多光谱遥感影像,对城市树木地上生物量反... 城市树木作为城市绿地的主要组成部分,承担着多项重要生态功能,其地上生物量反映了城市生态系统的碳储存能力和生态健康水平。面对传统地上生物量测定方法在复杂城市环境下的诸多限制,本研究基于多光谱遥感影像,对城市树木地上生物量反演方法进行探究。首先基于二维高斯模型将单木生物量进行扩散以建立样地生物量,并综合基于归一化植被指数(normalized difference vegetation index,NDVI)的统计特征以及影像提取的光谱、纹理特征以构建多维特征集。通过实验,比较了多元线性回归、支持向量回归、随机森林回归和多层感知机4种模型在生物量估算上的有效性,结果显示多层感知机模型表现最优,并基于该模型对研究区域内的树木地上生物量进行了反演、制图以及分析,为城市绿化管理和生态监测提供了新的技术流程和科学依据。本研究以南京市建邺区北部为例,得到区域内城市树木总地上生物量约为90 466.491 8 t,地上生物量密度最高可达约11.5 kg/m^(2). 展开更多
关键词 城市树木 地上生物量 多光谱遥感影像 回归模型
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Decellularized amniotic membrane promotes the anti-inflammatory response of macrophages via PI3K/AKT/HIF-1α pathway 被引量:2
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作者 Xiongbo Song Jinwen Xiao +2 位作者 Juan Wu Li Sun long chen 《Chinese Chemical Letters》 2025年第1期403-407,共5页
Macrophages undergo dynamic transitions between M1 and M2 states,exerting profound influences on both inflammatory and regenerative processes.The biocompatible and wound-healing properties of decellularized amniotic m... Macrophages undergo dynamic transitions between M1 and M2 states,exerting profound influences on both inflammatory and regenerative processes.The biocompatible and wound-healing properties of decellularized amniotic membrane(d AM)make it a subject of exploration for its potential impact on the anti-inflammatory response of macrophages.Experimental findings unequivocally demonstrate that d AM promotes anti-inflammatory M2 polarization of macrophage,with its cytokine-rich content posited as a potential mediator.The application of RNA sequencing unveils differential gene expression,implicating the hypoxia inducible factor-1α(HIF-1α)signaling pathway in this intricate interplay.Subsequent investigation further demonstrates that d AM facilitates anti-inflammatory M2 polarization of macrophage through the upregulation of epidermal growth factor(EGF),which,in turn,activates the phosphatidylinositol 3-kinase(PI3K)/protein kinase B(AKT)pathway and stabilizes HIF-1α.This cascade results in a noteworthy augmentation of anti-inflammatory gene expression.This study significantly contributes to advancing our comprehension of d AM's immunomodulatory role in tissue repair,thereby suggesting promising therapeutic potential. 展开更多
关键词 MACROPHAGE Decellularized amniotic membrane Anti-inflammatory response Hypoxia inducible factor-1α Epidermal growth factor
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Safety assessment of overcharged batteries and a novel passive warning method based on relaxation expansion force 被引量:1
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作者 long chen Shaohong Zeng +4 位作者 Jiahua Li Kuijie Li Ruixin Ma Jizhen Liu Weixiong Wu 《Journal of Energy Chemistry》 2025年第6期595-607,I0013,共14页
Due to batteries inconsistencies and potential faults in battery management systems,slight overcharging remains a common yet insufficiently understood safety risk,lacking effective warning methods.To illuminate the de... Due to batteries inconsistencies and potential faults in battery management systems,slight overcharging remains a common yet insufficiently understood safety risk,lacking effective warning methods.To illuminate the degradation behavior and failure mechanism of various overcharged states(100%SOC,105%SOC,110%SOC,and 115%SOC),multiple advanced in-situ characterization techniques(accelerating rate calorimeter,electrochemical impedance spectroscopy,ultrasonic scanning,and expansion instrument)were utilized.Additionally,re-overcharge-induced thermal runaway(TR)tests were conducted,with a specific emphasis on the evolution of the expansion force signal.Results indicated significant degradation at 110%SOC including conductivity loss,loss of lithium inventory,and loss of active material accompanied by internal gas generation.These failure behaviors slow down the expansion force rate during reovercharging,reducing the efficacy of active warnings that depend on rate thresholds of expansion force.Specifically,the warning time for 115%SOC battery is only 144 s,which is 740 s shorter than that for fresh battery,and the time to TR is advanced by 9 min.Moreover,the initial self-heating temperature(T1)is reduced by 62.4℃compared to that of fresh battery,reaching only 70.8℃.To address the low safety of overcharged batteries,a passive overcharge warning method utilizing relaxation expansion force was proposed,based on the continued gas generation after stopping charging,leading to a sustained increase in force.Compared to active methods that rely on thresholds of expansion force rate,the passive method can issue warnings 115 s earlier.By combining the passive and active warning methods,guaranteed effective overcharge warning can be issued 863-884 s before TR.This study introduces a novel perspective for enhancing the safety of batteries. 展开更多
关键词 Lithium-ion battery Slight overcharging Thermal runaway Overcharging warning Safety assessment Relaxation expansion force
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不同生境对多花黄精生长的影响
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作者 何慎 龙晨 +4 位作者 李恂 欧惠玲 罗小平 杨艳 高绍利 《湖南林业科技》 2025年第6期70-74,共5页
为研究不同生境对多花黄精生长的影响,本文以3年生多花黄精为研究对象,开展桂花、黄柏、杉木及油茶林下间作试验,测量多花黄精的主要生长量指标、叶形态指标、叶片SPAD值、生物量指标并进行多重比较和方差分析。结果表明:林下间作多花... 为研究不同生境对多花黄精生长的影响,本文以3年生多花黄精为研究对象,开展桂花、黄柏、杉木及油茶林下间作试验,测量多花黄精的主要生长量指标、叶形态指标、叶片SPAD值、生物量指标并进行多重比较和方差分析。结果表明:林下间作多花黄精的生长与叶形态、叶片SPAD值及生物量积累等方面均表现出显著优势。黄柏林下多花黄精的块茎鲜质量、块茎干质量、单株鲜质量、单株干质量及苗高分别为289.43 g、83.28 g、402.09 g、108.37 g及123.00 cm,显著高于其他处理(P<0.05),较非林下处理分别高49.34%、44.38%、54.68%、46.27%及33.22%;油茶林下的多花黄精叶片SPAD值、叶片鲜质量、块茎鲜质量及块茎干质量表现优异,分别为47.12、24.13 g、269.98 g及73.15 g,较非林下处理分别高9.94%、25.94%、39.31%及26.82%;杉木林下的多花黄精叶长、叶宽、叶片厚度、叶片SPAD值及地径分别为19.94 cm、6.14 cm、0.36 mm、53.28及12.03 mm,显著高于其他处理(P<0.05),较非林下处理分别高21.44%、16.51%、38.46%、24.31%及25.05%。桂花林下的多花黄精茎秆干质量(含浆果)、叶片鲜质量分别为18.31 g、24.77 g,均显著高于其他处理(P<0.05),较非林下处理分别高75.38%、29.28%。综上,林下间作是实现多花黄精高效栽培的核心策略。黄柏林是多花黄精块茎高产的最优生境,油茶林下间作为平衡经济效益与生产成本最具有潜力的模式,杉木和桂花林下间作也表现出显著优势。本研究结果为实践“以林育药、以药促林”的可持续发展模式提供了实证支撑。 展开更多
关键词 多花黄精 油茶 黄柏 桂花 杉木 生境
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A review of transformer models in drug discovery and beyond 被引量:1
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作者 Jian Jiang long chen +7 位作者 Lu Ke Bozheng Dou Chunhuan Zhang Hongsong Feng Yueying Zhu Huahai Qiu Bengong Zhang Guo-Wei Wei 《Journal of Pharmaceutical Analysis》 2025年第6期1187-1201,共15页
Transformer models have emerged as pivotal tools within the realm of drug discovery,distinguished by their unique architectural features and exceptional performance in managing intricate data landscapes.Leveraging the... Transformer models have emerged as pivotal tools within the realm of drug discovery,distinguished by their unique architectural features and exceptional performance in managing intricate data landscapes.Leveraging the innate capabilities of transformer architectures to comprehend intricate hierarchical dependencies inherent in sequential data,these models showcase remarkable efficacy across various tasks,including new drug design and drug target identification.The adaptability of pre-trained trans-former-based models renders them indispensable assets for driving data-centric advancements in drug discovery,chemistry,and biology,furnishing a robust framework that expedites innovation and dis-covery within these domains.Beyond their technical prowess,the success of transformer-based models in drug discovery,chemistry,and biology extends to their interdisciplinary potential,seamlessly combining biological,physical,chemical,and pharmacological insights to bridge gaps across diverse disciplines.This integrative approach not only enhances the depth and breadth of research endeavors but also fosters synergistic collaborations and exchange of ideas among disparate fields.In our review,we elucidate the myriad applications of transformers in drug discovery,as well as chemistry and biology,spanning from protein design and protein engineering,to molecular dynamics(MD),drug target iden-tification,transformer-enabled drug virtual screening(VS),drug lead optimization,drug addiction,small data set challenges,chemical and biological image analysis,chemical language understanding,and single cell data.Finally,we conclude the survey by deliberating on promising trends in transformer models within the context of drug discovery and other sciences. 展开更多
关键词 TRANSFORMER Drug discovery Chemical language understanding Molecular dynamics Protein design
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Biomaterials for surgical repair of osteoporotic bone defects 被引量:1
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作者 Xu Luo Jinwen Xiao +6 位作者 Qiming Yang Xiaolong Lu Qianjun Huang Xiaojun Ai Bo Li Li Sun long chen 《Chinese Chemical Letters》 2025年第1期92-98,共7页
As the global population ages,osteoporotic bone fractures leading to bone defects are increasingly becoming a significant challenge in the field of public health.Treating this disease faces many challenges,especially ... As the global population ages,osteoporotic bone fractures leading to bone defects are increasingly becoming a significant challenge in the field of public health.Treating this disease faces many challenges,especially in the context of an imbalance between osteoblast and osteoclast activities.Therefore,the development of new biomaterials has become the key.This article reviews various design strategies and their advantages and disadvantages for biomaterials aimed at osteoporotic bone defects.Overall,current research progress indicates that innovative design,functionalization,and targeting of materials can significantly enhance bone regeneration under osteoporotic conditions.By comprehensively considering biocompatibility,mechanical properties,and bioactivity,these biomaterials can be further optimized,offering a range of choices and strategies for the repair of osteoporotic bone defects. 展开更多
关键词 Osteoporotic bone defect BIOMATERIALS NANOMATERIALS Bone tissue engineering Bone regeneration
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基于DEMATEL-ISM的应急物流服务供应链协同影响因素与能力提升研究
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作者 王擎天 龙晨 王忠伟 《供应链管理》 2025年第8期40-53,共14页
为提升应急物流服务供应链协同能力,分析应急物流服务供应链协同的关键影响因素,构建应急物流服务供应链协同影响因素结构层次模型,提出针对性政策建议,为推动国家应急管理体系和能力现代化提供决策支持。运用扎根理论筛选应急物流服务... 为提升应急物流服务供应链协同能力,分析应急物流服务供应链协同的关键影响因素,构建应急物流服务供应链协同影响因素结构层次模型,提出针对性政策建议,为推动国家应急管理体系和能力现代化提供决策支持。运用扎根理论筛选应急物流服务供应链协同关键影响因素,运用决策与实验室方法和解释结构模型组合方法开展影响因素分析,分析各影响因素之间的关联,确定影响因素层级。结果表明,物资需求预测能力等6个影响因素位于结构层次模型第一层,为直接影响因素;应急机制完善程度等10个影响因素位于第二层和第三层,为中间影响因素,通过影响直接因素间接对应急物流服务供应链协同产生影响;责任与风险明确程度和物流服务供应商准入机制2个影响因素是深层影响因素,对应急物流服务供应链协同产生根本影响。根据研究结果,文章从建立供应商准入机制、推进应急物流技术数智化升级、提升应急物资“最后一公里”配送效率等角度提出具体协同能力提升对策。 展开更多
关键词 应急物流体系 应急物资 物流服务供应链 影响因素识别 DEMATEL-ISM
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KG-CNNDTI:a knowledge graph-enhanced prediction model for drug-target interactions and application in virtual screening of natural products against Alzheimer’s disease 被引量:1
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作者 chengyuan Yue Baiyu chen +7 位作者 long chen Le Xiong Changda Gong Ze Wang Guixia Liu Weihua Li Rui Wang Yun Tang 《Chinese Journal of Natural Medicines》 2025年第11期1283-1292,共10页
Accurate prediction of drug-target interactions(DTIs)plays a pivotal role in drug discovery,facilitating optimization of lead compounds,drug repurposing and elucidation of drug side effects.However,traditional DTI pre... Accurate prediction of drug-target interactions(DTIs)plays a pivotal role in drug discovery,facilitating optimization of lead compounds,drug repurposing and elucidation of drug side effects.However,traditional DTI prediction methods are often limited by incomplete biological data and insufficient representation of protein features.In this study,we proposed KG-CNNDTI,a novel knowledge graph-enhanced framework for DTI prediction,which integrates heterogeneous biological information to improve model generalizability and predictive performance.The proposed model utilized protein embeddings derived from a biomedical knowledge graph via the Node2Vec algorithm,which were further enriched with contextualized sequence representations obtained from ProteinBERT.For compound representation,multiple molecular fingerprint schemes alongside the Uni-Mol pre-trained model were evaluated.The fused representations served as inputs to both classical machine learning models and a convolutional neural network-based predictor.Experimental evaluations across benchmark datasets demonstrated that KG-CNNDTI achieved superior performance compared to state-of-the-art methods,particularly in terms of Precision,Recall,F1-Score and area under the precision-recall curve(AUPR).Ablation analysis highlighted the substantial contribution of knowledge graph-derived features.Moreover,KG-CNNDTI was employed for virtual screening of natural products against Alzheimer's disease,resulting in 40 candidate compounds.5 were supported by literature evidence,among which 3 were further validated in vitro assays. 展开更多
关键词 Drug-target interactions prediction Knowledge graph Drug screening Alzheimer’s disease Natural products
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ACtriplet:An improved deep learning model for activity cliffs prediction by integrating triplet loss and pre-training 被引量:1
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作者 Xinxin Yu Yimeng Wang +3 位作者 long chen Weihua Li Yun Tang Guixia Liu 《Journal of Pharmaceutical Analysis》 2025年第8期1837-1847,共11页
Activity cliffs(ACs)are generally defined as pairs of similar compounds that only differ by a minor structural modification but exhibit a large difference in their binding affinity for a given target.ACs offer crucial... Activity cliffs(ACs)are generally defined as pairs of similar compounds that only differ by a minor structural modification but exhibit a large difference in their binding affinity for a given target.ACs offer crucial insights that aid medicinal chemists in optimizing molecular structures.Nonetheless,they also form a major source of prediction error in structure-activity relationship(SAR)models.To date,several studies have demonstrated that deep neural networks based on molecular images or graphs might need to be improved further in predicting the potency of ACs.In this paper,we integrated the triplet loss in face recognition with pre-training strategy to develop a prediction model ACtriplet,tailored for ACs.Through extensive comparison with multiple baseline models on 30 benchmark datasets,the results showed that ACtriplet was significantly better than those deep learning(DL)models without pretraining.In addition,we explored the effect of pre-training on data representation.Finally,the case study demonstrated that our model's interpretability module could explain the prediction results reasonably.In the dilemma that the amount of data could not be increased rapidly,this innovative framework would better make use of the existing data,which would propel the potential of DL in the early stage of drug discovery and optimization. 展开更多
关键词 Activity cliff Triplet loss Deep learning Pre-training
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基于拉曼光谱-层次聚类分析的葡萄酒品质控制研究 被引量:6
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作者 张正勇 李晓烨 +4 位作者 龙宸 姜逸雪 沙敏 王海燕 刘军 《分析科学学报》 CAS CSCD 北大核心 2019年第1期8-12,共5页
本文提出了一种以拉曼光谱为输入,采用层次聚类分析为手段的葡萄酒品质控制新方法。实验以张裕干红葡萄酒为主要研究对象,分别采集了样品在激光积分时间1~5s的拉曼光谱信息,运用层次聚类法,定量分析了同品牌不同系列(张裕干红葡萄酒、... 本文提出了一种以拉曼光谱为输入,采用层次聚类分析为手段的葡萄酒品质控制新方法。实验以张裕干红葡萄酒为主要研究对象,分别采集了样品在激光积分时间1~5s的拉曼光谱信息,运用层次聚类法,定量分析了同品牌不同系列(张裕干红葡萄酒、张裕酿酒师赤霞珠干红葡萄酒、张裕干红葡萄酒(佐餐级)),以及不同品牌(张裕干红葡萄酒、王朝干红葡萄酒、长城干红葡萄酒)间品质差异,并进行了实验参数优化。结果显示,张裕干红葡萄酒在欧氏距离结合平均距离法,激光积分时间4s表征条件下,可实现其与同品牌不同系列,以及不同品牌葡萄酒间的高效区分。本文所提快速检测方法具有光谱信号获取速度快,算法自动化分析程度高等优势。 展开更多
关键词 拉曼光谱 层次聚类分析 相似度 葡萄酒 品质控制
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基于CLSVOF方法的离心喷嘴雾化过程计算及试验验证
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作者 林培华 陈思 +2 位作者 龙陈 钟显朴 刘元壮 《燃气涡轮试验与研究》 2025年第4期39-47,共9页
为实现双油路离心喷嘴雾化性能的高稳定性数值模拟研究,提出一种基于水平集−流体体积耦合(CLSVOF)的喷嘴内外流雾化过程耦合计算方法,并通过试验对其计算精度进行验证。该方法运用Fluent软件计算分别获得副油路和主油路的出口液膜环参数... 为实现双油路离心喷嘴雾化性能的高稳定性数值模拟研究,提出一种基于水平集−流体体积耦合(CLSVOF)的喷嘴内外流雾化过程耦合计算方法,并通过试验对其计算精度进行验证。该方法运用Fluent软件计算分别获得副油路和主油路的出口液膜环参数,并将其作为初始条件导入CLSVOF仿真工具计算喷嘴在不同进出口压降下的雾化性能。结果表明:计算与试验的喷嘴喷雾场宏观形态相似;流量计算结果相较于试验结果偏小,误差在−9.0%以内;副油路喷雾锥角随压降的增大而减小,双油路喷雾锥角随压降的增大而增大,喷雾锥角计算结果相较于试验结果偏大,误差在10.0%以内;副油路喷雾索太尔平均直径(SMD)随压降的增大而减小,双油路喷雾SMD随压降的增大而增大,SMD计算结果相较于试验结果偏大,误差在15.0%以内。该方法的计算精度在不同压降下均可接受且具备较高稳定性,可以作为双油路离心喷嘴的设计参考依据。 展开更多
关键词 双油路离心喷嘴 内外流雾化 CLSVOF 压降 喷嘴流量 喷雾锥角 SMD 燃烧室
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Malignant ascites enhance γδT cell cytotoxicity toward ovarian cancer via chemokine-mediated recruitment
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作者 Zhanqun Yang Ying Liu +8 位作者 Mengzhu Zheng Hui Li Ruoyao Cui Pan Wang Tianhui He Hongyan Guo Yinglin Zhou Jian Lin long chen 《Cancer Biology & Medicine》 2025年第6期639-643,共5页
Ovarian cancer remains a leading cause of gynecological cancer mortality1,and patients with advanced stage ovarian cancer frequently develop malignant ascites that foster immunosuppressive microenvironments and therap... Ovarian cancer remains a leading cause of gynecological cancer mortality1,and patients with advanced stage ovarian cancer frequently develop malignant ascites that foster immunosuppressive microenvironments and therapeutic resistance2,3.Although ascites have traditionally been considered detrimental,we report a paradoxical role in which they enhance the cytotoxicity ofγδT cells—a unique T cell subset that can be allogenically transferred for cancer treatment4,5—toward ovarian cancer. 展开更多
关键词 therapeutic resistance malignant ascites ovarian cancer enhance cytotoxicity immunosuppressive microenvironments t cell subset T cells CYTOTOXICITY
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Unintentional emissions of polychlorinated naphthalenes in China:Sources,composition,and historical trends
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作者 Ye Huang Lin Huang +14 位作者 Ying Li Nazupar Sidikjan Yunshan Zhang Yan chen Yangmin chen Ye Li Wei Du long chen YanWu Shanshan Zhang Jing Yang Wenjun Meng Guofeng Shen Min Liu Shu Tao 《Journal of Environmental Sciences》 2025年第2期221-229,共9页
Polychlorinated naphthalenes(PCNs)are detrimental to human health and the environment.With the commercial production of PCNs banned,unintentional releases have emerged as a significant environmental source.However,rel... Polychlorinated naphthalenes(PCNs)are detrimental to human health and the environment.With the commercial production of PCNs banned,unintentional releases have emerged as a significant environmental source.However,relevant information is still scarce.In this study,provincial emissions for eight PCNs homologues from 37 sources in the Chinese mainland during the period of 1960-2019 were estimated based on a source-specific and time-varying emission factor database.The results showed that the total PCNs emissions in 2019 reached 757.0 kg with Hebei ranked at the top among all the provinces and iron&steel industry as the biggest source.Low-chlorinated PCNs comprised 90%of emissions by mass,while highly chlorinated PCNs dominated in terms of toxicity,highlighting divergent priorities for mitigating emissions and safeguarding human health.The emissions showed an overall upward trend from 1960 to 2019 driven by emission increase from iron&steel industry in terms of source,and from North China and East China in terms of geographic area.Per-capita emissions followed an inverted U-shaped environmental Kuznets curvewhile emission intensities decreased with increasing per-capita Gross Domestic Product(GDP)following a nearly linear pattern when log-transformed. 展开更多
关键词 PCNS Emission inventory Emission factor Composition profile Emission intensity Chinese mainland
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Correction to:A Virtual Reality Platform for Context-Dependent Cognitive Research in Rodents
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作者 Xue‑Tong Qu Jin‑Ni Wu +8 位作者 Yunqing Wen long chen Shi‑Lei Lv Li Liu Li‑Jie Zhan Tian‑Yi Liu Hua He Yu Liu Chun Xu 《Neuroscience Bulletin》 2025年第5期932-932,共1页
In the Acknowledgements section of this article,the grant number"2020YFE0205900"relating to"National Key R&D Program of China"was missing,it has been included and the corrected Acknowledgements... In the Acknowledgements section of this article,the grant number"2020YFE0205900"relating to"National Key R&D Program of China"was missing,it has been included and the corrected Acknowledgements section is given below. 展开更多
关键词 cognitive research virtual reality national key R D program acknowledgements RODENTS grant number
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