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Ultra-wide band gap and wave attenuation mechanism of a novel star-shaped chiral metamaterial

Applied mathematics and Mechanics(English Edition) 2024年第7期45卷 1261-1278页

作者： Shuo WANG Anshuai WANG Yansen WU Xiaofeng LI Yongtao SUN Zhaozhan ZHANG Qian DING G.D.AYALEW yunxiang ma Qingyu LIN Department of Mechanics Tianjin UniversityTianjin300350China Tianjin Key Laboratory of Nonlinear Dynamics and Control Tianjin UniversityTianjin300350China State Key Laboratory of Metastable materials Science and Technology Yanshan UniversityQinhuangdao066004Hebei ProvinceChina

A novel hollow star-shaped chiral metamaterial(SCM)is proposed by incorporating chiral structural properties into the standard hollow star-shaped metamaterial,exhibiting a wide band gap over 1500 *** broaden the band gap,solid single-phase and two-phase SCMs are designed and simulated,which produce two ultra-wide band gaps(approximately 5116 Hz and 6027 Hz,respectively).The main reason for the formation of the ultra-wide band gap is that the rotational vibration of the concave star of two novel SCMs drains the energy of an elastic *** impacts of the concave angle of a single-phase SCM and the resonator radius of a two-phase SCM on the band gaps are *** the concave angle leads to an increase in the width of the widest band gap,and the width of the widest band gap increases as the resonator radius of the two-phase SCM ***,the study on elastic wave propagation characteristics involves analyzing frequency dispersion surfaces,wave propagation directions,group velocities,and phase ***,the analysis focuses on the transmission properties of finite periodic *** solid single-phase SCM achieves a maximum vibration attenuation over 800,while the width of the band gap is smaller than that of the two-phase *** metamaterials exhibit high vibration attenuation capabilities,which can be used in wideband vibration reduction to satisfy the requirement of ultra-wide frequencies.

关键词： metamaterial ultra-wide band gap wave propagation vibration suppression

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水力脉动下抽水蓄能机组扭振特性辨识方法

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动力工程学报 2024年第6期44卷 859-864页

作者：马运翔刘晓锋何小锋彭辉曹扬江苏方天电力技术有限公司南京211102

提出一种基于水力脉动的抽水蓄能机组轴系扭振特性辨识方法,即采用应变测试技术获取随机性动态扭矩信号;设置触发阈值,将扭矩信号和阈值的交点及其后一定长度的样本点组成样本信号;对足够多样本平均后,信号中随机响应和正/负速度冲击响... 详细信息

提出一种基于水力脉动的抽水蓄能机组轴系扭振特性辨识方法,即采用应变测试技术获取随机性动态扭矩信号;设置触发阈值,将扭矩信号和阈值的交点及其后一定长度的样本点组成样本信号;对足够多样本平均后,信号中随机响应和正/负速度冲击响应被平均掉,剩余则为幅值冲击响应信号;用指数函数拟合冲击响应信号,从中得到扭振固有频率和阻尼。将该方法应用于某抽水蓄能机组扭振特性辨识。试验结果表明:25%负荷工况下水力脉动幅度较大,触发阈值对阻尼和频率辨识结果的影响较小;负荷升高后扭矩脉动幅度减小,触发阈值对频率识别值的影响较小,但会影响阻尼识别值;该方法无需施加扭矩激励,可以实现安装状态下扭振特性辨识,具有较强的工程应用价值。

关键词：水轮机抽水蓄能扭振固有频率阻尼

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Lanthanide Inorganic Solids Based on main Group Borates and Oxyanions of Lone Pair Cations

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Chinese Journal of Chemistry 2018年第1期36卷 63-72页

作者： Fang Kong yunxiang ma Jianggao mao State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences Fuzhou Fujian 350002 China College of Chemistry Fuzhou University Fuzhou Fujian 350116 China

Lanthanide borates containing post transition metal main group elements, including Ga（Ⅲ）, Ge（Ⅳ）, Sb（Ⅴ） and Te（Ⅵ）, as well as lanthanide salts of the oxyanions of lone pair cations, such as I（Ⅴ）, Se（Ⅳ） and Te（Ⅳ）, were reviewed. The post transition metal main group elements in lanthanide borates adopt octahedral or tetrahedral geometry only. In the structure of lanthanide galloborates, only octahedral GaO6 was found while both octahedral GeO6 and tetrahedral GeO4 appeared in borogermanates. The fifth period elements Sb（Ⅴ） and Te（VI） prefer octahedral coordination geometry in lanthanide borates system. The second groups introduced to lanthanide oxyanions of lone pairs are mainly focused on do TM units, such as WO4 tetrahedron, VO5 square pyramid or MoO6 octahedron, and rigid tetrahedral groups like sulfate SO4, silica SiO4 or selenate SeO4 units. Divalent cations like Pb（Ⅱ） and magnetic ions of Cu（Ⅱ） or Mn（Ⅱ） were also included. The structure chemistry of lanthanide ions in these systems is rich. Coordination numbers from six to ten are discovered, yielding a wide range of coordination geometries including the pentagonal bipyramid, square antiprism, metabidiminished icosahedron, tricapped trigonal prism, capped triangular cupola, etc. The connectivity modes between the Ln polyhedra are miscellaneous, from 3D network, to 2D layer, 1D chain, tetramer, trimer, dimer and finally monomer. A number of compounds display NCS structures and strong SHG response, and many lanthanide compounds exhibit good luminescent properties in visible and IR region.

关键词： lanthanide inorganic solid borate iodate selenite tellurite

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覆岩导水裂隙带发育高度动态演化规律研究

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煤矿安全 2024年第2期55卷 176-183页

作者：赵兵朝冯杰赵阳侯恩科马云祥冯欣怡西安科技大学能源学院陕西西安710054 西安科技大学西部矿井开采及灾害防治教育部重点实验室陕西西安710054 西安科技大学地质与环境学院陕西西安710054 国能宁夏煤业集团有限责任公司红柳煤矿宁夏银川751400

为了研究覆岩导水裂隙带发育高度动态演化规律,以小保当矿区2^(-2)煤层为研究对象,通过理论分析、相似模拟实验及实例验证的方法,对导水裂隙带动态发育高度进行研究;借助概率积分法预计其上部岩层移动变形的理论公式,给出了1种基于覆岩... 详细信息

为了研究覆岩导水裂隙带发育高度动态演化规律,以小保当矿区2^(-2)煤层为研究对象,通过理论分析、相似模拟实验及实例验证的方法,对导水裂隙带动态发育高度进行研究;借助概率积分法预计其上部岩层移动变形的理论公式,给出了1种基于覆岩曲率变形的导水裂隙带动态发育高度预计方法。研究表明:导水裂隙带上部岩层下沉系数是1个与挠度及下部自由空间高度相关的分段函数,上部岩层曲率变形大小是决定导水裂隙带发育高度的关键因素;导水裂隙带发育高度与工作面推进长度相关;理论预计小保当矿区2^(-2)煤层导水裂隙带发育高度为160.8 m,相似模拟实验发育高度为155 m,现场实测发育高度为152.01~175.57 m。

关键词：导水裂隙带动态演化下沉系数曲率变形概率积分法

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丁香酸多孔淀粉酯的制备与表征

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食品与发酵工业 2024年第7期50卷 197-202页

作者：陈瑞喜马云翔李建刚张晓萌周治屹陈金凤汪月张盛贵甘肃农业大学理学院甘肃兰州730070 甘肃农业大学食品科学与工程学院甘肃兰州730070

以马铃薯多孔淀粉(porous starch,PS)为材料,制备具有较好溶解性和抗氧化性的丁香酸多孔淀粉酯(syringic acid porous starch ester,SA@PS)。实验通过N 2-吸/脱附、扫描电镜、傅里叶变换红外光谱、液态核磁等方法,研究了SA@PS的特性。... 详细信息

以马铃薯多孔淀粉(porous starch,PS)为材料,制备具有较好溶解性和抗氧化性的丁香酸多孔淀粉酯(syringic acid porous starch ester,SA@PS)。实验通过N 2-吸/脱附、扫描电镜、傅里叶变换红外光谱、液态核磁等方法,研究了SA@PS的特性。结果表明,以PS(比表面积14.69 m^(2)/g)为主体,可制备取代度为0.06~0.25的SA@PS;傅里叶变换红外光谱和液体核磁共振氢谱证明SA和PS之间形成了酯键;X射线衍射表明酯化反应改变了淀粉的结晶类型;SA@PS具备较强的抗氧化活性,可用于光、氧化或高温敏感分子的保护材料。

关键词：多孔淀粉丁香酸酯化反应结构表征

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GDMNet: A Unified Multi-Task Network for Panoptic Driving Perception

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Computers, materials & Continua 2024年第8期80卷 2963-2978页

作者： yunxiang Liu Haili ma Jianlin Zhu Qiangbo Zhang School of Computer Science and Information Engineering Shanghai Institute of TechnologyShanghai201418China

To enhance the efficiency and accuracy of environmental perception for autonomous vehicles,we propose GDMNet,a unified multi-task perception network for autonomous driving,capable of performing drivable area segmentation,lane detection,and traffic object ***,in the encoding stage,features are extracted,and Generalized Efficient Layer Aggregation Network(GELAN)is utilized to enhance feature extraction and gradient ***,in the decoding stage,specialized detection heads are designed;the drivable area segmentation head employs DySample to expand feature maps,the lane detection head merges early-stage features and processes the output through the Focal Modulation Network(FMN).Lastly,the Minimum Point Distance IoU(MPDIoU)loss function is employed to compute the matching degree between traffic object detection boxes and predicted boxes,facilitating model training *** results on the BDD100K dataset demonstrate that the proposed network achieves a drivable area segmentation mean intersection over union(mIoU)of 92.2%,lane detection accuracy and intersection over union(IoU)of 75.3%and 26.4%,respectively,and traffic object detection recall and maP of 89.7%and 78.2%,*** detection performance surpasses that of other single-task or multi-task algorithm models.

关键词： Autonomous driving multitask learning drivable area segmentation lane detection vehicle detection

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甲地孕酮联合运动疗法在晚期肺癌恶病质患者中的临床疗效及对生活质量的影响

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潍坊医学院学报 2024年第2期46卷 117-120页

作者：张敏马云香姜文昌刘炳玉李广燕杨景伟青州市人民医院肿瘤科山东潍坊262500 青州市人民医院检验医学科青州市人民医院影像科青州市人民医院摆药中心青州市人民医院消毒供应室青州市人民医院胸外科

目的探讨甲地孕酮、营养支持联合运动疗法在晚期肺癌恶病质患者中的临床疗效及对患者生活质量的影响。方法选取2021年1月~2023年1月于青州市人民医院肿瘤科住院的晚期肺癌恶病质患者60例,随机分为对照组30例和观察组30例;对照组患者... 详细信息

目的探讨甲地孕酮、营养支持联合运动疗法在晚期肺癌恶病质患者中的临床疗效及对患者生活质量的影响。方法选取2021年1月~2023年1月于青州市人民医院肿瘤科住院的晚期肺癌恶病质患者60例,随机分为对照组30例和观察组30例;对照组患者予以甲地孕酮+营养支持疗法,观察组患者予以甲地孕酮+营养支持联合运动疗法,30d为1个治疗周期。比较治疗后两组患者的临床自觉症状、卡氏评分、患者体重及营养状况(血清白蛋白、血清前白蛋白)。结果联合干预治疗后,观察组临床症状改善明显优于对照组(P<0.05),两组患者干预治疗后临床疗效均较治疗前明显改善(P<0.05),观察组患者卡氏评分优于对照组(P<0.05),联合干预治疗后两组患者体重及营养状况较治疗前明显改善(P<0.05),且观察组体重及营养状况优于对照组(P<0.05)。结论甲地孕酮联合运动疗法能改善晚期肺癌恶病质患者的临床症状,增加体重,提高KPS评分,改善营养状况及提高患者生活质量。

关键词：甲地孕酮运动疗法肺癌恶病质营养状况生活质量

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Nonlinear sealing force of a seawater balance valve used in an 11000-meter manned submersible

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Frontiers of Mechanical Engineering 2023年第1期18卷 287-301页

作者： Zhenyao WANG Yinshui LIU Qian CHENG Runzhou XU yunxiang ma Defa WU School of Mechanical Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China

Balance valve is a core component of the 11000-meter manned submersible“struggle,”and its sealing performance is crucial and challenging when the maximum pressure difference is 118 *** increasing sealing force improves the sealing performance and increases the system’s energy consumption at the same time.A hybrid analytical–numerical–experimental(ANE)model is proposed to obtain the minimum sealing force,ensuring no leakage at the valve port and reducing energy consumption as much as *** effects of roundness error,environmental pressure,and materials on the minimum sealing force are considered in the ANE *** basic form of minimum sealing force equations is established,and the remaining unknown coefficients of the equations are obtained by the finite element method(FEM).The accuracy of the equation is evaluated by comparing the independent FEM data to the equation *** of the comparison show good agreement,and the difference between the independent FEM data and equation data is within 3%when the environmental pressure is 0–118 ***,the minimum sealing force equation is applied in a balance valve to be experimented using a deep-sea simulation *** balance valve designed through the minimum sealing force equation is leak-free in the ***,the minimum sealing force equation is suitable for the ultrahigh pressure balance valve and has guiding significance for evaluating the sealing performance of ultrahigh pressure balance valves.

关键词： seawater balance valve sealing performance hybrid ANE model FEM minimum sealing force equation

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An ultra-sensitive biosensor for circulating microRNA detection with Fe single-atom enhanced cathodic luminol-O_(2) electrochemiluminescence

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Nano Research 2024年第9期17卷 7926-7934页

作者： Yudie Sun yunxiang Han Mingyue Wang Mingfu Ye Konglin Wu Kui Zhang School of Chemistry and Chemical Engineering Anhui University of TechnologyMa'anshan 243032China Key Laboratory of Optic-electric Sensing and Analytical Chemistry for Life Science MOEQingdao University of Science and TechnologyQingdao 266042China Engineering Research Center of Biofilm Water Purification and Utilization Technology of Ministry of Education Anhui University of TechnologyMa'anshan 243032China

Circulating microRNAs(miRNAs)play a pivotal role in the occurrence and development of acute myocardial infarction(AMI),and precise detection of them holds significant clinical *** development of luminol-based luminophores in the field of electrochemiluminescence(ECL)for miRNA detection has been significant,while their effectiveness is hindered by the instability of co-reactant hydrogen peroxide(H_(2)O_(2)).In this work,an iron single-atom catalyst(Fe-PNC)was employed for catalyzing the luminol-O_(2) ECL system to achieve ultra-sensitive detection of myocardial *** miRNA triggers a hybridization chain reaction(HCR),resulting in the generation of a DNA product featuring multiple sticky ends that facilitate the attachment of Fe-PNC probes to the electrode *** Fe-PNC catalyst exhibits high promise and efficiency for the oxygen reduction reaction(ORR)in electrochemical energy conversion *** resulting ECL biosensor allowed ultrasensitive detection of myocardial miRNA with a low detection limit of 0.42 fM and a wide linear range from 1 fM to 1.0 ***,it demonstrates exceptional performance when evaluated using serum samples collected from patients with *** work expands the application of single-atom catalysis in ECL sensing and introduces novel perspectives for utilizing ECL in disease diagnosis.

关键词： circulating miRNAs single-atom catalyst luminol-O_(2) electrochemiluminescence hybridization chain reaction

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General synthesis of transition metal nitride arrays by ultrafast flash Joule heating within 500 ms

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Science China Chemistry 2024年第6期67卷 1976-1982页

作者： Peiqi Shen Jiahui Zhao Yanan Gao yunxiang Lin Yuchen Han Kun Xu School of Chemistry and Chemical Engineering Key Laboratory of Functional Inorganic Material Chemistry of Anhui ProvinceAnhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized MaterialsKey Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of EducationAnhui UniversityHefei230601China Institutes of Physical Science and Information Technology Center of Free Electron Laser&High Magnetic FieldLeibniz International Joint Research Center of Materials Sciences of Anhui ProvinceAnhui UniversityHefei230601China

Transition metal nitrides(TMNs)are considered as viable alternatives to noble metal catalysts owing to their versatile electronic structure and favorable catalytic ***,the conventional synthetic processes for TMNs suffer from high energy consumption and low production *** this study,a range of TMNs and their hetero-composite arrays were successfully synthesized via an ultrafast flash Joule heating technology within 0.5 *** a proof concept,the nitrides and hetero-composites were applied for the electrocatalytic hydrazine oxidation reaction(HzOR),in which the Co_(4)N/Mo_(16)N_(7)arrays shows the best performance with a geometric current density of 100 ma cm^(-2)at 23 mV(*** hydrogen electrode(RHE)).This work paves a new way for the ultrafast synthesis of TMNs which could meet the ever-increased energy crisis.

关键词： flash Joule heating rapid synthesis transition metal nitrides hydrazine oxidation reaction electrocatalysts

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