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Trees as large-scale natural phononic crystals: Simulation and experimental verification

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International Soil and Water Conservation Research 2019年第2期7卷 196-202页

作者： jiankun huang Yifan Liu Yaguang Li Key Laboratory of State Forestry Administration on Soil and Water Conservation School of Soil and Water ConservationBeijing Forestry UniversityBeijingChina

Urban trees are usually planted on a periodic layout in the spatial *** regard urban trees as large-scale natural phononic *** entire forest is reduced to a reasonable 'tree-soil' unit cell based on the phononic crystal theory and finite element method by COMSOL software is used to obtain the dispersion *** Rayleigh wave band gaps of phononic trees are distinguished by the sound cone *** influences of soil elastic modulus and tree height on band gaps are investigated.A three-dimensional simulation model and experiment test are applied to validate the effect of phononic trees on vibration *** numerical frequency reduction zones coincide exactly with the theoretical band *** soil stiffness results in a higher-frequency and wider band *** increasing tree height is beneficial to obtain low-frequency band gaps.A periodically arranged plantation that Rayleigh wave band gaps at frequency ≤60 Hz could be *** study opens up a new theoretical basis for the quantitative analyses of urban trees to the ground vibration mitigation at a certain frequency range.

关键词： Urban trees Phononic crystal Dispersion curve Band gap Rayleigh wave

基于改进Bi-RRT算法的机器鱼路径规划方法

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山东大学学报（工学版） 2024年第1期54卷 74-82页

作者：黄健堃薛钢刘延俊王雨李厚池白发刚山东大学机械工程学院山东济南250061 山东大学高效洁净机械制造教育部重点实验室山东济南250061 山东大学机械工程国家级实验教学示范中心山东济南250061 山东大学海洋研究院山东青岛266237

为提高机器鱼的水下路径规划效率,更好地完成水下工作,提出一种基于改进双向快速搜索随机树(bidirectional rapidly-exploring random trees,Bi-RRT)算法的机器鱼路径规划方法。以研制的混合驱动机器鱼为研究对象,介绍其结构模型和运动... 详细信息

为提高机器鱼的水下路径规划效率,更好地完成水下工作,提出一种基于改进双向快速搜索随机树(bidirectional rapidly-exploring random trees,Bi-RRT)算法的机器鱼路径规划方法。以研制的混合驱动机器鱼为研究对象,介绍其结构模型和运动控制模式,为后续试验验证提供物理样机。针对Bi-RRT算法存在的采样随机、路径冗余、效率不高等问题,融合生长引导机制和连接强化机制改进Bi-RRT算法,加入生长引导机制,改善随机树生长随机、两树连接慢的问题;加入连接强化机制提高算法搜索速度。对搜索路径进行优化处理,通过剔除冗余节点、插入优化节点,改善路径质量,对路径进行平滑处理,使路径更适合机器鱼航行,实现机器鱼路径规划任务。仿真结果表明,与传统Bi-RRT算法及其他衍生快速搜索随机树(rapidly-exploring random tree,RRT)算法相比,改进的Bi-RRT算法相较于改进前节点数减少约50.8%,路径长度缩短约19%,搜索时间减少约65.3%。

关键词：机器鱼 Bi-RRT算法路径规划节点简化路径平滑

Artificial intelligence-assisted colorimetry for urine glucose detection towards enhanced sensitivity,accuracy,resolution,and anti-illuminating capability

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Nano Research 2023年第10期16卷 12084-12091页

作者： Fan Feng Zeping Ou Fangdou Zhang Jinxing Chen jiankun huang Jingxiang Wang Haiqiang Zuo Jingbin Zeng State Key Laboratory for Heavy Oil Processing College of Chemistry and Chemical EngineeringChina University of Petroleum(East China)Qingdao 266580China College of New Energy China University of Petroleum(East China)Qingdao 266580China Institute of Functional Nano&Soft Materials(FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials&DevicesSoochow UniversitySuzhou 215123China Qingdao Fifth People’s Hospital Qingdao 266580China

Colorimetry often suffers from deficiency in quantitative determination,susceptibility to ambient illuminance,and low sensitivity and visual resolution to tiny color *** offset these deficiencies,we incorporate deep machine learning into colorimetry by introducing a convolutional neural network(CNN)with powerful parallel processing,self-organization,and self-learning *** a proof of concept,a plasmonic nanosensor is proposed for the colorimetric detection of glucose by coupling Benedict’s reagent with gold nanoparticles(AuNPs),which relies on the assemble of AuNPs into dendritic nanochains by *** distinct difference of refractive index between Cu2O and Au and the localized surface plasmon resonance coupling effect among AuNPs leads to a broad spectral shift as well as abundant color changes,thereby providing sufficient data for selflearning enabled by machine *** CNN is then used to fully diversify the learning and training of the images from standard samples under different ambient conditions and to obtain a classifier that can not only recognize tiny color changes that are imperceptible to human eyes,but also exhibit high accuracy and excellent anti-environmental interference *** classifier is then compiled as an application(APP)and implanted into a smartphone with Android environment.306 clinical urine samples were detected using the proposed method and the results showed a satisfactory correlation(87.6%)with that of a standard blood glucose test *** importantly,this method can be generalized to other applications in colorimetry,and more broadly,in other scientific domains that involve image analysis and quantification.

关键词： artificial intelligence colorimetry urine glucose plasmonic nanosensor smartphone platform

Magnetic rod-based metal-organic framework metal composite as multifunctional nanostirrer with adsorptive,peroxidase-like and catalytic properties

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Chinese Chemical Letters 2021年第10期32卷 3245-3251页

作者： Benjamin Edem Meteku jiankun huang Jingbin Zeng Sobia Aslam Yu Zhang Xue Zhang Bingwen Cui Cong-ying Wen Zifeng Yan College of Science and State Key Laboratory of Heavy Oil Processing China University of Petroleum(East China)Qingdao 266580China College of Chemical Engineering China University of Petroleum(East China)Qingdao 266580China Department of Chemistry Abdul Wali Khan UniversityMardan 23200Pakistan

Although magnetic stirring is frequently used to enhance the kinetics for adsorption,chemical and biochemical reactions,the introduction of stirrers inevitably leads to the adsorption of analytes and thus interferes with the efficiency of the chemical process or *** this work,magnetic Fe_(3) O_(4) nanorods with tunable length-to-diameter ratio were synthesized via a hydrothermal method and used as templates for the in-situ depositing of MIL-100(Fe) and gold *** nanorod-based material can not only function as an adsorbent,nanozyme,and a heterogeneous catalyst for corresponding applications but also serve as a magnetic nanostirrer to enhance *** a proof-of-concept,the capture of bacteria pathogen,mimic-peroxidase-based colorimetric detection of hydrogen peroxide,and the catalytic reduction of selected organic pollutants were conducted using the as-synthesized Fe_(3) O_(4)@MIL-100(Fe)-Au nanostirrer with and without magnetic *** results show that the rates of bacteria capture,mimetic enzyme reaction and catalysis were tremendously *** believe this magnetic field-assisted approach holds great promise for future applications,because,not only does it eliminate the use of external magnetic stirrers and thereby decrease the risk of foreign pollution but also,is adaptable for nanoscale reaction systems where conventional stirring is not applicable due to size limitations.

关键词： Nanostirrer Nanozyme Magnetic field MOF Adsorption Catalysis

In-plane attenuation zone and its optimization in a plate with periodic holes

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Chinese Journal of Acoustics 2019年第1期38卷 85-98页

作者： LIU Xiongwei huang jiankun HU Yucun LI Yaguang LIU Wen Department of Civil Engineering School of Soil and Water ConservationBeijing Forestry University

It is difficult to design a plate with wide attenuation zones in low frequency region based on Bragg scattering mechanism. A plate with periodic rhombic holes is optimized and designed. Based on the finite element method under periodic boundary conditions, the in-plane dispersion curves of periodically perforated plate are calculated via COMSOL. The frequency responses of periodically perforated plate axe investigated via ANSYS simulation. The plates with periodic holes are suspended and dynamically tested under sinusoidal excitations. The results show that a periodically perforated plate with rhombus holes has wider attenuation zones than plates with circular and hexagonal holes. Material properties have a great influence on attenuation zones: nitrile-butadiene rubber and silicon rubber can easily obtain low-frequency zones, while increasing porosity creates lower and wider zones. The width of attenuation zone increases as the horizontal angle of the rhombus holes increases. An analysis of the attenuation zones* generation mechanism shows that the plate with periodic holes exhibits characteristics of Bragg scattering and local resonant phononic crystal, indicating an inherent relationship between two types of mechanisms. The optimized plate has a complete attenuation zone ranging from 5281.76-8824.30 Hz. The vibrations are significantly reduced when the number of periods is no less than two. The attenuation range obtained via the numerical method is generally consistent with the experiment. The research sheds light on the noise insulation plate and has the potential to improve the sound environment in various applications due to its simple manufacturing.

关键词： In-plane attenuation zone plate with periodic holes COMSOL

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后张预应力梁封端缝渗漏治理

北京交通大学学报 2010年第1期34卷 58-63,67页

作者：黄建坤石志飞北京交通大学土木建筑工程学院北京100044

由于后张预应力梁封端混凝土与梁体混凝土的浇注时间不同,形成封端缝,进而造成封端混凝土渗漏并引起锚具锈蚀和预应力的损失,严重影响行车安全.文中提出了一种能在12 cm(及以上)的狭窄伸缩缝环境下对封端缝渗漏进行治理的方案.首先改进... 详细信息

由于后张预应力梁封端混凝土与梁体混凝土的浇注时间不同,形成封端缝,进而造成封端混凝土渗漏并引起锚具锈蚀和预应力的损失,严重影响行车安全.文中提出了一种能在12 cm(及以上)的狭窄伸缩缝环境下对封端缝渗漏进行治理的方案.首先改进了适用于该狭窄环境的基面清理工具,通过实验室模拟试验、材料性能测试和数值模拟,证实了本基面清理工具的实用性和本方案的可行性,进而将该方案成功的应用于神朔铁路大柳塔—府谷段6孔梁的现场渗漏治理.为检验治理效果,开发了一种集信号输出与数字采集于一体的渗漏检测仪样机,测试对比表明,样机具有较高的精度和较大的量程,完全可以满足工程需要.

关键词：后张预应力梁封端缝渗漏治理渗漏检测

VIBRATION REDUCTION FOR PLANE WAVES BY USING PERIODIC PILE BARRIERS

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VIBRATION REDUCTION FOR PLANE WAVES BY USING PERIODIC PILE B...

Ultrasmall NiFe layered double hydroxide strongly coupled on atomically dispersed FeCo-NC nanoflowers as efficient bifunctional catalyst for rechargeable Zn-air battery

铁道工程新技术：第二届铁道工程关键技术国际学术会议

作者： jiankun huang Zhifei SHI School of Civil Engineering Beijing Jiaotong University Beijing 100044

＜正＞Many researchers have analyzed the screening effectiveness of a row（s） of piles and used them to reduce the environmental ***,the periodic nature of rows of piles has been *** that are arranged in a periodic configuration constitute a type of periodic structures. Band of frequency gaps（BFGs） exists in these periodic *** waves with frequencies in the range of the BFGs cannot propagate in the *** this paper,the theory of periodic structures is utilized to study the vibration reduction by using rows of *** plane wave expansion method and COMSOL program are used to study the BFGs of two-dimensional（2D） three-component periodic pile *** effect of filling fraction on the first complete BFGs is *** order to verify the effectiveness,a 2D pile-soil finite element model is built,and input loads with different frequencies are *** analysis and numerical simulation show the frequency zones of vibration reduction are consistent with the *** present investigation provides a new method for designing pile barriers to block mid-frequency vibration due to train.

关键词： periodic structure environmental vibration isolation band of frequency gaps pile barrier

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Science China Materials 2020年第7期63卷 1182-1195页

作者： Yiyan Wang Guoxin Zhang Mang Ma Yan Ma jiankun huang Chen Chen Ying Zhang Xiaoming Sun Zifeng Yan State Key Laboratory of Heavy Oil Processing China University of Petroleum(East China)Qingdao 266580China Department of Electrical Engineering and Automation Shandong University of Science and TechnologyQingdao 266590China

An atomically dispersed FeCo-NC material with the 3D flower-like morphology was used as a unique substrate for the controllable deposition of ultrasmall NiFe layered double hydroxide nanodots(termed as NiFe-NDs)to simultaneously promote the sluggish kinetics of oxygen reduction reaction(ORR)and oxygen evolution reaction(OER).The size-limiting growth of NiFe-NDs(~4.0 nm in diameter)was realized via the confinement of the 3D flower-like mesoporous structure and the rich N/O functionality of *** from the distinctive structure with the simultaneously maximum exposure of both OER and ORR active sites,the NiFe-ND/FeCo-NC composite showed an ORR halfwave potential of 0.85 V and an OER potential of 1.66 V in0.1 mol L-1KOH at 10.0 mA ***-situ Raman analysis suggested the activity of OER was derived from the Ni sites on NiFe-ND/***,the NiFe-ND/FeCo-NC-assembled Zn-air battery(ZAB)exhibited a very small discharge-charge voltage gap of 0.87 V at 20 mA cm-2and robust cycling ***,the NiFe-ND/FeCo-NC composite was also applicable for fabricating all-solid-state ZAB to power wearable electronics with superior cycling stability under *** work could enlighten a new applicable branch of atomically dispersed metal-nitrogen-carbon materials as unique substrates for fabricating multifunctional electrocatalysts.

关键词： atomically dispersed catalyst NiFe layered double hydroxide oxygen electrocatalyst bifunctionality zinc-air battery

仿生机器鱼水动力学与机构动力学耦合建模研究

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西安交通大学学报 2022年第9期56卷 46-56页

作者：白发刚薛钢黄健堃刘延俊山东大学海洋研究院山东青岛266237 山东大学高效洁净机械制造教育部重点实验室济南250061 山东大学机械工程国家级实验教学示范中心济南250061 山东大学机械工程学院济南250061

针对多关节仿生机器鱼自主游动过程的复杂动力学建模问题,利用中枢模式发生器产生机器鱼的关节驱动信号,采用细长体理论和Newton-Euler法建立了机器鱼水动力学和机构动力学耦合模型。将机器鱼物理模型的尾部关节角摆动规律作为动力学模... 详细信息

针对多关节仿生机器鱼自主游动过程的复杂动力学建模问题,利用中枢模式发生器产生机器鱼的关节驱动信号,采用细长体理论和Newton-Euler法建立了机器鱼水动力学和机构动力学耦合模型。将机器鱼物理模型的尾部关节角摆动规律作为动力学模型的运动输入,对比了数值仿真结果与物理模型实验结果,验证了耦合动力学模型的准确性。分析了机器鱼尾部关节间相位差、摆动角频率和摆动幅值对机器鱼游动性能的影响。结果表明:摆动角频率和最大摆动幅度在一定范围内与平均游速近似成正比,与头部稳定性成反比;相较于平均游速,头部稳定性对关节间相位差的变化更加敏感,较大的尾部关节间相位差能够获得更好的游动稳定性。相关结论可为进一步研究仿生机器鱼复杂轨迹跟踪问题提供前提和理论基础。

关键词：仿生机器鱼耦合建模 Newton-Euler法水动力学