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Nano-sized stationary phase packings retained by single-particle frit for microchip liquid chromatography

Chinese Chemical Letters 2024年第4期35卷 486-489页

作者： wangyan hu Ke Li Xiangnan Dou Ning Li Xiayan Wang Center Excellence for Environmental Safety and Biological Effects Beijing Key Laboratory for Green Catalysis and SeparationDepartment of ChemistryBeijing University of TechnologyBeijing 100124China Center for Environmental Metrology National Institute of MetrologyBeijing 100029China

Modern chromatography is increasingly focused on miniaturization and integration. Compared to conventional liquid chromatography, microfluidic chip liquid chromatography(microchip-LC) has the potential due to its zero-dead volume connection and ease of integration. Nano-sized packings have the potential to significantly enhance separation performance in microchip-LC. However, their application has been hindered by packing difficulties. This study presents a method for packing nano-sized silica particles into a microchannel as the stationary phase. The microchip-LC packed column was prepared by combining the weir and the porous silica single-particle as frit to retain the packing particles. A surface tensionbased single-particle picking technique was established to insert porous single-particle frit into glass microchannels. Additionally, we developed a slurry packing method that utilizes air pressure to inject nano-sized packing into the microchannel. Pressure-driven chromatographic separation was performed using this nano-packed column integrated into a glass microchip. The mixture of four PAHs was successfully separated within just 8 min using a 5 mm separation channel length, achieving high theoretical plates(10~6plates/m). Overall, these findings demonstrate the potential of utilizing nano-sized packings for enhancing chromatographic performance in microchip systems.

关键词： Nano-size packing Single-particle frit Packed column Microchip LC Chromatographic separation

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高钢栈桥设计与施工研究

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交通科技 2016年第5期26卷 43-45页

作者：杜娟王彦虎张盛威东南大学成贤学院土木与交通工程学院南京210088 中建六局土木工程有限公司天津300457

针对通顺河大桥施工受通顺河汛期影响严重的难题,提出了高钢栈桥设计与施工的思想。通过对高钢栈桥设计思路、结构设计、结构验算、施工工艺及施工要点进行分析论证,结合通顺河大桥工程具体实例,不仅方便了施工,而且满足了通顺河VI级通... 详细信息

针对通顺河大桥施工受通顺河汛期影响严重的难题,提出了高钢栈桥设计与施工的思想。通过对高钢栈桥设计思路、结构设计、结构验算、施工工艺及施工要点进行分析论证,结合通顺河大桥工程具体实例,不仅方便了施工,而且满足了通顺河VI级通航的需要,证明了高钢栈桥设计与施工方法的可行性和有效性。

关键词：钢栈桥施工设计钢管桩

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人工智能指纹识别技术在警务实战中的应用

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刑事技术 2021年第3期46卷 299-304页

作者：徐杰刘哲元霍鑫蒋敬戴玉阳胡王燕张家港市公安局江苏张家港215600 公安部第三研究所上海201204 南京森林警察学院南京210023

大数据时代,海量指纹数据的汇聚对指纹识别系统的比对精度和速度带来了挑战。能否实现对现场指纹图片在海量样本库中的“以图搜图”,即无需对指纹图片进行特征编辑即可快速比对(无特征比对),是一线部门提出的实战需求。本文以“云痕”... 详细信息

大数据时代,海量指纹数据的汇聚对指纹识别系统的比对精度和速度带来了挑战。能否实现对现场指纹图片在海量样本库中的“以图搜图”,即无需对指纹图片进行特征编辑即可快速比对(无特征比对),是一线部门提出的实战需求。本文以“云痕”智能指纹识别系统为例,介绍一种将人工智能引入指纹识别领域,采用自适应小波框架与主动式深度学习的比对技术和总线级协同计算的计算技术,建设指纹亿级数据库的技术创新,使得指纹的比对精度和速度得到提升。结合笔者单位警务工作,介绍了“云痕”系统应用于电脑端和移动端的指纹比对场景,对比分析了人工智能与传统指纹识别系统在指纹表述信息量及比对精度等方面的技术优势,并对人工智能在指纹识别方面的应用前景进行了展望。

关键词：人工智能指纹自动识别以图搜图无特征比对

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Copper fluoride as a low-cost sodium-ion battery cathode with high capacity

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Chinese Chemical Letters 2022年第3期33卷 1435-1438页

作者： Yiming Dai Qiujie Chen Chenchen hu Yangyang huang wangyan Wu Mingliang Yu Dan Sun Wei Luo Institute of New Energy for Vehicles School of Materials Science and EngineeringTongji UniversityShanghai 201804China CAS Key Laboratory of Design and Assembly of Functional Nanostructures and Fujian Provincial Key Laboratory of NanomaterialsFujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China Haixi Institute Xiamen Institute of Rare Earth MaterialsChinese Academy of SciencesXiamen 361021China

Sodium-ion batteries (SIBs) are promising alternatives to lithium-ion batteries (LIBs) for large-scale energy storage considering the abundance and low cost of Na-containing resources. However, the energy density of SIBs has been limited by the typically low specific capacities of traditional intercalation-based cathodes. Metal fluorides, in contrast, can deliver much higher capacities based on multi-electron conversion reactions. Among metal fluorides, CuF_(2) presents a theoretical specific capacity as high as 528 mAh/g while its Na-ion storage mechanism has been rarely reported. Here, we report CuF_(2) as a SIB cathode, which delivers a high capacity of 502 mAh/g but suffers from poor electrochemical reversibility. As a solution, we adjust the cell configuration by inserting a carbon-coated separator, which hinders the transportation of dissolved Cu ions and improves the reversibility of the CuF_(2) cathode. By using in-situ XRD measurements and theoretical calculation, we propose that a one-step conversion reaction occurs during the discharge process, and a reconversion reaction competes with the oxidization of Cu to dissolved Cu ion during the charge process.

关键词： Sodium-ion battery Copper fluoride Cathode Energy density Conversion reaction

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An attack-resilient distributed extended Kalman consensus filtering algorithm with applications to multi-UAV tracking problems

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Frontiers of Information Technology & Electronic Engineering 2024年第8期25卷 1110-1122页

作者： Yuru hu wangyan LI Lifeng WU Zhensheng YU College of Science University of Shanghai for Science and TechnologyShanghai 200093China

This study investigates how the events of deception attacks are distributed during the fusion of multi-sensor nonlinear ***,a deception attack with limited energy(DALE)is introduced under the framework of distributed extended Kalman consensus filtering(DEKCF).Next,a hypothesis testing-based mechanism to detect the abnormal data generated by DALE,in the presence of the error term caused by the linearization of the nonlinear system,is *** the DALE is detected,a new rectification strategy can be triggered to recalibrate the abnormal data,restoring it to its normal ***,an attack-resilient DEKCF(AR-DEKCF)algorithm is proposed,and its fusion estimation errors are demonstrated to satisfy the mean square exponential boundedness performance,under appropriate ***,the effectiveness of the AR-DEKCF algorithm is confirmed through simulations involving multi-unmanned aerial vehicle(multi-UAV)tracking problems.

关键词： Extended Kalman consensus filtering Hypothesis testing Rectification strategy Multi-UAV tracking

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Dixon与Fat-Sat技术在眼眶T2加权成像中的图像质量对比研究

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南京医科大学学报（自然科学版） 2022年第12期42卷 1741-1744页

作者：刘王琰陈露胡昊刘俊南京医科大学第一附属医院放射科江苏南京210029

目的:对比Dixon和频率选择脂肪预饱和(frequency-selective fat-saturation,Fat-Sat)技术对眼眶T2加权成像(T2-weighted imaging,T2WI)的压脂效果和综合图像质量。方法:前瞻性纳入35例健康受试者,进行眼眶Dixon-T2WI(Dixon组)和Fat-Sat-T2WI(Fat-Sat组)扫描。对两组图像的脂肪抑制效果和综合图像质量进行主观评分。基于两组图像分别测量眼外肌和颞肌的信号强度,并计算信号强度比(signal intensity ratio,SIR)。采用Wilcoxon检验对两组图像主观评分进行比较。采用配对样本t检验对信号强度和SIR进行组间比较。结果:Dixon组的脂肪抑制效果高于Fat-Sat组(3.86±0.36 vs. 2.91±0.56,P <0.001),综合图像质量也高于Fat-Sat组(3.83±0.38 vs. 3.26±0.56,P <0.001)。Dixon组眼外肌信号强度高于Fat-Sat组(362.33±107.73 vs. 286.59±78.84,P <0.001),颞肌信号强度也高于Fat-Sat组(207.26±63.41 vs. 170.19±51.93,P <0.001),而两组图像的SIR差异无统计学意义(1.83±0.54 vs. 1.77±0.49,P=0.239)。结论:与Fat-Sat技术比较,基于Dixon技术的眼眶T2WI压脂效果和图像质量更优,而SIR相仿,可以为临床提供更可靠的诊断依据。

关键词：眼眶磁共振成像脂肪抑制 Dixon

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轨道车辆车内声品质客观评价分析

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噪声与振动控制 2014年第5期34卷 61-64页

作者：扈凯王岩松上海工程技术大学汽车工程学院上海201620

对上海轨道车辆9号线在不同运行速度下头部车厢、中部车厢和车厢连接处进行噪声现场测试,引入心理声学声品质参数:A计权声压级、特征响度、尖锐度、粗糙度和抖动强度,对不同工况下轨道车辆车内声场进行声品质的客观评价。结论表明,轨道... 详细信息

对上海轨道车辆9号线在不同运行速度下头部车厢、中部车厢和车厢连接处进行噪声现场测试,引入心理声学声品质参数:A计权声压级、特征响度、尖锐度、粗糙度和抖动强度,对不同工况下轨道车辆车内声场进行声品质的客观评价。结论表明,轨道车辆运行时车厢内部噪声以中低频噪声为主。随着车速提高,车内声品质下降,尤其是车厢连接处,声品质最差,应采取有效措施改善噪声环境,满足人耳的听觉舒适性。

关键词：声学轨道车辆声品质车内噪声客观评价

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轨道车辆车内声场仿真及声品质优化

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噪声与振动控制 2014年第4期34卷 174-177页

作者：扈凯王岩松上海工程技术大学汽车工程学院上海201620

以上海轨道交通九号线为例,对车内噪声进行现场测试,测量车厢结构参数并建立有限元模型,采用Actran软件进行声学仿真,并使用A计权声压级和特征响度两个主要的声品质客观评价参量验证仿真的结果,随后提出声品质优化方案,使车内声压级降低... 详细信息

以上海轨道交通九号线为例,对车内噪声进行现场测试,测量车厢结构参数并建立有限元模型,采用Actran软件进行声学仿真,并使用A计权声压级和特征响度两个主要的声品质客观评价参量验证仿真的结果,随后提出声品质优化方案,使车内声压级降低5 dB,特征响度总体下降,总响度值降低1.26 sone,对提高车内声品质和改善车内声场环境具有一定的参考价值。

关键词：声学轨道车辆车内声场 Actran仿真声品质优化

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