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地铁列车刨削式防爬吸能结构冲击力平稳行为参数优化

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铁道科学与工程学报 2024年第3期21卷 1232-1243页

作者：许平魏鲁宁邢杰关月溪杨雨晖郭维年杨丽婷中南大学交通运输工程学院教育部轨道交通安全重点实验室湖南长沙410075 中南大学铁道车辆安全技术国家与地方联合工程研究中心湖南长沙410075

为提升地铁列车在碰撞过程的平稳性和耐撞性,提出一种刨削式吸能防爬器。该吸能结构因其抗偏载能力强,结构紧凑等优点被广泛应用于地铁列车的端部吸能结构中。以某型地铁列车的刨削式防爬器为研究对象,使用有限元仿真的方式建立该吸能... 详细信息

为提升地铁列车在碰撞过程的平稳性和耐撞性,提出一种刨削式吸能防爬器。该吸能结构因其抗偏载能力强,结构紧凑等优点被广泛应用于地铁列车的端部吸能结构中。以某型地铁列车的刨削式防爬器为研究对象,使用有限元仿真的方式建立该吸能结构的对称简化模型,并结合台车冲击的试验数据验证有限元模型的准确性;通过数值仿真的方式,将刨刀前角(α)、刨刀后角(β)、刨刀宽度(w)和刨削深度(d)作为输入变量,以总吸能量(E_(A))和吸能阶段的平均刨削力(M_(PF))为耐撞性指标,以样本方差(S^(2))作为考核参照,通过全因子法对输入变量进行参数化分析;在此基础上,利用径向基函数构建代理模型,并采用多目标遗传算法(MOGA)对该吸能结构的主要设计参数进行优化设计,以确定结构参数的最佳的配置方案。研究结果表明:在该型刨削式防爬吸能结构的主要设计尺寸参数中,β对E_(A)、M_(PF)以及S^(2)的影响均不明显;α对MPF、E_(A)呈负相关,同时与S^(2)呈正相关;w和d对E_(A)与M_(PF)呈正相关、与S^(2)呈负相关;通过优化设计得到的吸能结构的最优的参数设计方案中:d为3.94 mm;α为7.78°,w为34 mm;最优设计方案的E_(A)提高了5.91%,M_(PF)提高了5.89%,S^(2)降低了45.4%,耐撞性与平稳性得到了提高。研究结果可为地铁列车刨削式防爬吸能结构的设计提供工程参考。

关键词：地铁列车刨削式防爬器耐撞性台车试验平稳性多目标优化

Self‑Assembly MXene‑rGO/CoNi Film with Massive Continuous Heterointerfaces and Enhanced Magnetic Coupling for Superior Microwave Absorber

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Nano-Micro Letters 2022年第5期14卷 20-33页

作者： Xiao Li Zhengchen Wu Wenbin You liting yang Renchao Che Laboratory of Advanced Materials Shanghai Key Lab of Molecular Catalysis and Innovative MaterialsFudan UniversityShanghai 200438People’s Republic of China Department of Materials Science Fudan UniversityShanghai 200438People’s Republic of China

MXene, as a rising star of two-dimensional(2 D) materials, has been widely applied in fields of microwave absorption and electromagnetic shielding to cope with the arrival of the 5 G era. However, challenges arise due to the excessively high permittivity and the difficulty of surface modification of few-layered MXenes severely, which infect the microwave absorption performance. Herein, for the first time, a carefully designed and optimized electrostatic selfassembly strategy to fabricate magnetized MXene-r GO/Co Ni film was reported. Inside the synthesized composite film, r GO nanosheets decorated with highly dispersed Co Ni nanoparticles are interclacted into MXene layers, which effectively suppresses the originally self-restacked of MXene nanosheets, resulting in a reduction of high permittivity. In addition, owing to the strong magnetic coupling between the magnetic Fe Co alloy nanoparticles on the r GO substrate, the entire MXener GO/Co Ni film exhibits a strong magnetic loss capability. Moreover, the local dielectric polarized fields exist at the continuous heterointerfaces between 2 D MXene and r GO further improve the capacity of microwave loss. Hence, the synthesized composite film exhibits excellent microwave absorption property with a maximum reflection loss value of-54.1 d B at 13.28 GHz. The electromagnetic synergy strategy is expected to guide future exploration of high-efficiency MXene-based microwave absorption materials.

关键词： MXene Microwave absorption Composite materials Graphene Electron holography

抗坏血酸-磷酸溶液超声提取-高效液相色谱-电感耦合等离子体质谱法快速测定土壤中6种砷形态的含量

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理化检验（化学分册） 2024年第8期60卷 770-774页

作者：杨丽婷隆星星王艳萍郭怀兰张垚湖北医药学院生物医药研究院十堰442000 湖北医药学院南水北调水源地环境与健康研究中心十堰442000 湖北医药学院公共卫生与健康学院十堰442000 赛默飞世尔科技(中国)应用中心上海200125

为解决高效液相色谱-电感耦合等离子体质谱法(HPLC-ICP-MS)测定土壤中6种砷形态含量时色谱分离时间长以及亚砷酸根[As(Ⅲ)]易转化成砷酸根[As(Ⅴ)]的问题,进行了题示研究。在0.1 g土壤样品中添加体积比1∶1的1.6 mol·L^(-1)磷酸溶液和0... 详细信息

为解决高效液相色谱-电感耦合等离子体质谱法(HPLC-ICP-MS)测定土壤中6种砷形态含量时色谱分离时间长以及亚砷酸根[As(Ⅲ)]易转化成砷酸根[As(Ⅴ)]的问题,进行了题示研究。在0.1 g土壤样品中添加体积比1∶1的1.6 mol·L^(-1)磷酸溶液和0.5 mol·L^(-1)抗坏血酸溶液的混合溶液10 mL,常温下超声提取6 h,用水稀释至50 mL,经0.22μm聚醚砜膜过滤,用HPLC-ICP-MS测定滤液中砷甜菜碱(AsB)、As(Ⅲ)、二甲基砷(DMA)、砷胆碱(AsC)、一甲基砷(MMA)和As(Ⅴ)等6种砷形态的含量。在色谱分析中,以Dionex IonPac AG7色谱柱(50 mm×4 mm,10μm)为分析柱和保护柱,不同体积比的3.5 mmol·L^(-1)碳酸铵溶液和100 mmol·L^(-1)碳酸铵溶液的混合溶液为流动相进行梯度洗脱。结果显示:6种砷形态的质量浓度均在一定范围内和峰面积呈线性关系,检出限(3S/N)为0.010~0.050μg·L^(-1);按照标准加入法进行回收试验,回收率为92.0%~110%,测定值的相对标准偏差(n=6)均小于5.0%。方法用于6个实际土壤样品的分析,检出了As(Ⅲ)和As(Ⅴ),检出量分别为0.07~0.15μg·g^(-1)和3.44~8.61μg·g^(-1)。

关键词：抗坏血酸高效液相色谱-电感耦合等离子体质谱法砷形态分析土壤

Direct imaging of stress-induced magnetic behavior transitions

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Journal of Materials Science & Technology 2023年第15期146卷 72-79页

作者： Wenbin You Gangjie Lian liting yang Ke Pei Yuyang Wu Jincang Zhang Renchao Che Laboratory of Advanced Materials Shanghai Key Lab of Molecular Catalysis and Innovative MaterialsDepartment of Materials ScienceFudan UniversityShanghai 200438China Zhejiang Laboratory Hangzhou 311100China Materials Genome Institute Shanghai UniversityShanghai 200444China

Stress induction plays a special role in performance control for material *** far,it has remained challenging to systematically investigate magnetoelectric effect under stress-mediated *** we constructed a magnetoelectric device with piezoelectric stress induction,in which the stress plays a crucial intermediate role during the controllable modification of the magnetic behavior transitions under the magnetic field or current pulse driven *** compressive stress was found to make the above process easier and reduce energy consumption via changing the magnetic domain energy ***,both the domain distribution and domain-wall driven process are sensitive to stress *** magnetoelectric device integrated the advantages of voltage-stress and spin-current for the control of magnetic behavior transition with the help of micro-nano *** the stress-induced magnetic behavior in magnetic materials was directly imaged and quantificationally investigated,the complex interactions between stress,magnetic domain motion,magnetic field,and spin current have been clarified.

关键词： Magnetic behavior Voltage-stress:spin-current Energy consumption

3D Seed-Germination-Like MXene with In Situ Growing CNTs/Ni Heterojunction for Enhanced Microwave Absorption via Polarization and Magnetization

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Nano-Micro Letters 2021年第10期13卷 252-265页

作者： Xiao Li Wenbin You Chunyang Xu Lei Wang liting yang Yuesheng Li Renchao Che Laboratory of Advanced Materials Shanghai Key Lab of Molecular Catalysis and Innovative MaterialsFudan UniversityShanghai 200438People’s Republic of China Department of Materials Science Fudan UniversityShanghai 200438People’s Republic of China

Ti_(3)C_(2)Tx MXene is widely regarded as a potential micro-wave absorber due to its dielectric multi-layered ***,missing magnetic loss capability of pure MXene leads to the unmatched electromagnetic parameters and unsatisfied impedance matching ***,with the inspiration from dielectric-magnetic synergy,this obstruction is solved by fabricating magnetic CNTs/Ni hetero-structure decorated MXene substrate via a facile in situ induced growth ***2+ions are successfully attached on the surface and interlamination of each MXene unit by intensive electrostatic *** from the possible“seed-germination”effect,the“seeds”Ni^(2+)grow into“buds”Ni nanoparticles and“stem”carbon nanotubes(CNTs)from the enlarged“soil”of MXene *** to the improved impedance matching con-dition,the MXene-CNTs/Ni hybrid holds a superior microwave absorp-tion performance of−56.4 dB at only 2.4 mm *** a distinctive 3D architecture endows the hybrids:(i)a large-scale 3D magnetic coupling network in each dielectric unit that leading to the enhanced magnetic loss capability,(ii)a massive multi-heterojunction interface structure that resulting in the reinforced polarization loss capability,confirmed by the off-axis electron *** outstanding results provide novel ideas for developing magnetic MXene-based absorbers.

关键词： Microwave absorption Two-dimensional materials MXene Magnetic coupling network Synergistic effect

In situ dynamics response mechanism of the tunable length-diameter ratio nanochains for excellent microwave absorber

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Nano Research 2020年第1期13卷 72-78页

作者： Wenbin You Ke Pei liting yang Xiao Li Xiaofeng Shi Xuefeng Yu Huiqiao Guo Renchao Che Laboratory of Advanced Materials Department of Materials Science and CollaborativeInnovation Center of Chemistry for Energy Materials(iChem)Fudan University220 Handan RoadShanghai200433China

Faster response benefits the high-performance of magnetic material in various live ***,enhancing response speed toward the applied field via engineering advantages in structures is highly *** this paper,the precise synthesis of Co nanochain with the tunable length-diameter ratio is realized via a magnetic-field-guided assembly *** Co nanochain exhibits enhanced microwave absorption performance(near to-60 dB,layer thickness 2.2 mm)and broader effective absorption bandwidth(over 2/3 of total S,C,X,Ku bands).Furthermore,the simulated dynamic magnetic response reveals that the domain motion in 1D chain is faster than that in 0D nanoparticle,which is the determining factor of magnetic loss ***,based on the controllable magnetic field experiment via in situ transmission electron microscopy,the association between magnetic response and microstructure is first present at the *** real and imaginary parts of relative complex permeability are determined by the domain migration confined inside Co nanochain and the magnetic flux field surrounded outside Co nanochain,***,these findings can be extended to the novel design of microwave absorbers and promising candidates of magnetic carriers based on 1D structure.

关键词： microwave absorption in situ transmission electron microscopy(TEM) magnetic materials cobalt nanochain dynamic response

毛竹林下植被演替过程中土壤颗粒组成与水分入渗特征

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南京林业大学学报（自然科学版） 2024年第3期48卷 108-116页

作者：谢燕燕郭子武林树燕左珂怡杨丽婷徐森谷瑞陈双林中国林业科学研究院亚热带林业研究所浙江杭州311400 南京林业大学竹类研究所江苏南京210037

【目的】测定毛竹(Phyllostachys edulis)林地不同土层土壤粒径组成、分布和水分入渗性能,揭示土壤粒径分布及水分入渗性能对林下植被演替的响应规律,为毛竹林地土壤生态管理与植被更新提供依据。【方法】以林下植被演替年限分别为0、9... 详细信息

【目的】测定毛竹(Phyllostachys edulis)林地不同土层土壤粒径组成、分布和水分入渗性能,揭示土壤粒径分布及水分入渗性能对林下植被演替的响应规律,为毛竹林地土壤生态管理与植被更新提供依据。【方法】以林下植被演替年限分别为0、9及21 a的毛竹林为研究对象,测定了林地不同土层,即[0,10)cm、[10,20)cm和[20,30)cm层土壤颗粒组成、土壤颗粒体积分形维数,采用Kostiakov、Philip和Horton模型模拟分析土壤水分入渗性能,解析土壤分形特征与颗粒组成、水分入渗性能的关系。【结果】同一演替年限毛竹林土壤黏粒、粉粒含量、分形维数和水分入渗性能均随土层深度增加而降低,而砂粒含量逐渐增加。随林下植被演替年限延长,[0,10)cm土层黏粒、粉粒含量及分形维数逐渐下降,砂粒含量逐渐增加,[10,20)cm和[20,30)cm土层黏粒、粉粒含量及分形维数呈先升高后下降的趋势,砂粒含量则与之相反;不同土层土壤初渗率和稳渗率总体呈升高的变化趋势;土壤分形维数与黏粉粒含量、初渗率和稳渗率均呈显著正相关关系(P<0.05),与砂粒含量呈显著负相关关系(P<0.05);Kostiakov与Horton模型更适用于试验毛竹林土壤水分入渗过程模拟。【结论】毛竹林下植被演替能够显著改善土壤粒径结构,提高土壤水分入渗性能,且呈现明显的演替时间效应,植被演替21 a毛竹林的土壤水分入渗性能明显优于植被演替9 a毛竹林和毛竹纯林的。

关键词：毛竹植被演替土壤粒径分形特征土壤水分入渗性能

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防风芎归汤加味联合依巴斯汀片治疗慢性荨麻疹血虚风燥证临床研究

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新中医 2024年第13期56卷 63-67页

作者：杨立婷楼丹灵李娟娟俞光辉杭州市第九人民医院皮肤科

目的：观察防风芎归汤加味联合依巴斯汀片治疗慢性荨麻疹（CU）血虚风燥证的临床疗效。方法：选取CU血虚风燥证患者76例，按随机数字表法分为对照组和观察组各38例。对照组给予依巴斯汀片治疗，观察组在对照组基础给予防风芎归汤加味治... 详细信息

目的：观察防风芎归汤加味联合依巴斯汀片治疗慢性荨麻疹（CU）血虚风燥证的临床疗效。方法：选取CU血虚风燥证患者76例，按随机数字表法分为对照组和观察组各38例。对照组给予依巴斯汀片治疗，观察组在对照组基础给予防风芎归汤加味治疗，2组均治疗8周。评价2组临床疗效，比较2组症状评分、皮肤病生活质量指数（DLQI）评分、凝血指标血清D-二聚体（D-D）和纤维蛋白原降解产物（FDP）水平，统计不良反应发生率。结果：观察组总有效率为97.37%，高于对照组78.95%(P0.05）。结论：防风芎归汤加味联合依巴斯汀片治疗CU血虚风燥证患者的临床疗效较好，可改善凝血功能，有助于患者症状体征与生活质量的好转。

关键词：慢性荨麻疹血虚风燥证防风芎归汤 D-二聚体纤维蛋白原降解产物生活质量

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384孔PCR仪温度参数校准方法探讨

计量与测试技术 2024年第4期51卷 116-118页

作者：郭振宇杨丽婷吴梦言姚乾文金昌市质量技术检测所北京林电伟业电子技术有限公司

PCR技术作为一项革命性的分子生物学工具,在基因分析、病原体检测、药物研发、遗传学研究等领域发挥着重要作用。384孔PCR仪作为高通量PCR仪的代表,具备一次性处理多个样本的能力。由于现有的校准规范主要针对96孔,使用384孔时存在校准... 详细信息

PCR技术作为一项革命性的分子生物学工具,在基因分析、病原体检测、药物研发、遗传学研究等领域发挥着重要作用。384孔PCR仪作为高通量PCR仪的代表,具备一次性处理多个样本的能力。由于现有的校准规范主要针对96孔,使用384孔时存在校准困难和准确性较差的问题。因此,本文通过对两者进行对比,提出了384孔PCR仪的校准布点方式,并进行试验验证。结果表明:采用该校准布点方式具有有效性。

关键词： PCR仪 384孔PCR仪温度校准