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Recent advances in small-scale hydrogel-based robots for adaptive biomedical applications

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Nano Research 2024年第2期17卷 649-662页

作者： mingzhe Nie Qilong Zhao Xuemin Du Institute of Biomedical&Health Engineering Shenzhen Institute of Advanced Technology(SIAT)Chinese Academy of Sciences(CAS)Shenzhen 518055China

Small-scale robots,ranging in size from micrometers to centimeters,have gained significant attention in the biomedical ***,conventional small-scale robots made of rigid materials encounter challenges in adapting themselves to the soft tissues and complicated environments of human *** to the rigid counterpart,small-scale hydrogel-based robots hold great promises due to their tissue-like low modulus,outstanding biocompatibility and accessible stimuli-responsive *** attributes offer small-scale hydrogel-based robots with multimodal locomotion and reinforced functions,further enhancing the adaptability in manipulation and tasks execution for various biomedical *** this review,we present recent advances in small-scale hydrogel-based *** first summarize the design principles of small-scale hydrogel-based robots including materials,fabrication techniques and manipulation strategies,then highlighting their upgraded functions and adaptive biomedical ***,we discuss existing challenges and future perspectives for small-scale hydrogel-based robots.

关键词： small-scale robot hydrogel locomotion multi-function adaptability

Power equipment vibration visualization using intelligent sensing method based on event-sensing principle

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Global Energy Interconnection 2024年第2期7卷 228-240页

作者： mingzhe Zhao Xiaojun Shen Lei Su Zihang Dong Tongji University No.1239 Siping RoadYangpu DistrictShanghai 200092P.R.China State Grid Shanghai Municipal Electric Power Company Electric Power Science Research Institute Shanghai 200437P.R.China Department of Electrical and Electronic Engineering Imperial College LondonLondonSW72AZU.K.

Vibration measurements can be used to evaluate the operation status of power equipment and are widely applied in equipment quality inspection and fault ***-sensing technology can sense the change in surface light intensity caused by object vibration and provide a visual description of vibration *** on the analysis of the principle underlying the transformation of vibration behavior into event flow data by an event sensor,this paper proposes an algorithm to reconstruct event flow data into a relationship correlating vibration displacement and time to extract the amplitude-frequency characteristics of the vibration signal.A vibration measurement test platform is constructed,and feasibility and effectiveness tests are performed for the vibration motor and other power *** results show that event-sensing technology can effectively perceive the surface vibration behavior of power and provide a wide dynamic ***,the vibration measurement and visualization algorithm for power equipment constructed using this technology offers high measurement accuracy and *** results of this study provide a new noncontact and visual method for locating vibrations and performing amplitude-frequency analysis on power equipment.

关键词： Power equipment Event sensing Non contact measurement Graphic display Feasibility

Wind disturbance compensated path-following control for fixed-wing UAVs in arbitrarily strong winds

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Chinese Journal of Aeronautics 2024年第2期37卷 431-445页

作者： Hao LU Lan GAO Yunda YAN mingzhe HOU Chenliang WANG Hangzhou Innovation Institute Beihang UniversityHangzhou 310051China School of Information Science and Technology Hangzhou Normal UniversityHangzhou 311121China Department of Computer Science University College LondonLondon WC1E 6BTUnited Kingdom Center for Control Theory and Guidance Technology Harbin Institute of TechnologyHarbin 150001China School of Automation Science and Electrical Engineering Beihang UniversityBeijing 100191China

Wind is the primary challenge for low-speed fixed-wing unmanned aerial vehicles to follow a predefined flight *** cope with various wind conditions,this paper proposes a wind disturbance compensated path following control strategy where the wind disturbance estimate is incorporated with the nominal guiding vector field to provide the desired airspeed direction for the *** the control input vector for the outer-loop kinematic subsystem needs to satisfy a magnitude constraint,a scaling mechanism is introduced to tune the proportions of the compensation and nominal ***,an optimization problem is formulated to pursue a maximum wind compensation in strong winds,which can be solved analytically to yield two scaling factors.A cascaded inner-loop tracking controller is also designed to fulfill the outer-loop wind disturbance compensated guiding vector ***-fidelity simulation results under sensor noises and realistic winds demonstrate that the proposed path following algorithm is less sensitive to sensor noises,achieves promising accuracy in normal winds,and mitigates the deviation from a desired path in wild winds.

关键词： Path following Guiding vector field Wind disturbance Disturbance rejection Fixed wings

Macro-micro behaviors and failure mechanism of frozen weakly cemented mudstone

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第4期16卷 1337-1347页

作者： Xianzhou lyu Jijie Du Hao Fu Dawei lyu Weiming Wang College of Earth Science and Engineering Shandong University of Science and TechnologyQingdao266590China College of Civil Engineering and Architecture Shandong University of Science and TechnologyQingdao266590China

Understanding the mechanical properties and multiscale failure mechanism of frozen soft rock is an important prerequisite for the construction safety of tunnels,artificially frozen ground and other infrastructure in cold *** this study,the triaxial compression test are performed on mudstone in the weakly cemented soft rock strata in the mining area of western China,and the mechanical characteristics and failure mechanism of weakly cemented mudstone are systematically investigated under the combined action of freezing and ***,the quantitative relationship between the microstructural parameters and the macroscopic strength and deformation parameters is established based on fractal ***,the failure mechanism of frozen weakly cemented mudstone is revealed on both micro- and *** results show that temperature and confining pressure significantly affects the elastic modulus and peak strength of weakly cemented *** decreasing temperature,the compressive strength increases,while the corresponding peak strain decreases *** the deformation curve,the plastic deformation stage is shortened,and the brittle fracture feature at the post-peak stage is more prominent,and the elastic modulus correspondingly increases with decreasing *** low-temperature conditions,most of the weakly cemented mudstone undergoes microscopic shear failure along the main fracture *** micro-fracture morphology characteristics of weakly cemented mudstone under different temperatures are quantified via the fractal dimension,and an approximately exponential relationship can be obtained among the fractal dimension and the temperature,compressive strength and elastic modulus.

关键词： Weakly cemented mudstone Artificial freezing Mechanical properties Linkage destruction mechanism Fractal dimension

Amorphous hybrid tungsten oxide–nickel hydroxide nanosheets used as a highly efficient electrocatalyst for hydrogen evolution reaction

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Nano Research 2024年第4期17卷 2499-2508页

作者： Chao lyu Chenghai Dai Yiwei Tan State Key Laboratory of Materials-Oriented Chemical Engineering School of Chemistry and Chemical EngineeringNanjing Tech UniversityNanjing 211816China

There are more challenges for alkaline hydrogen evolution reaction(HER)via simultaneously expediting the electron-coupled water dissociation process(Volmer step)and the following electrochemical H_(2) desorption(Heyrovsky step).Hybrid amorphous electrocatalysts are highly desirable for efficient hydrogen evolution from water-alkali electrolyzers due to the bifunctionality for the different elementary steps of HER and optimal interactions with water molecules and the reactive hydrogen intermediates(Had).Herein,the synthesis of amorphous hybrid ultrathin(tungsten oxide/nickel hydroxide)hydrate(a-[WO_(3)/Ni(OH)_(2)]·0.2H_(2)O)nanosheets on nickel foam(NF)for efficient alkaline HER is *** structural and composition features of a-[WO_(3)/Ni(OH)_(2)]·0.2H_(2)O are characterized in *** resulting a-[WO_(3)/Ni(OH)_(2)]·0.2H_(2)O/NF electrocatalyst with the synergistic effect of both hybrid components for the HER elementary steps shows greatly improved the activity and durability for the HER with a low overpotential of-41 and-163 mV at-10 and-500 mA·cm^(-2),respectively,a Tafel slope as low as-72.9 mV·dec^(-1),and long-term stability of continuous electrolysis for at least 150 h accompanying by inappreciable overpotential change in 1 M *** the hybrid a-[WO_(3)/Ni(OH)_(2)]·0.2H_(2)O,Ni(OH)_(2) and WO_(3) moieties are separately responsible for accelerating dissociative adsorption of water and weakening Had adsorption strength,which is beneficial to the improvement of the alkaline HER activity.

关键词： amorphous nanomaterial bimetallic electrocatalyst tungsten oxide ultrathin nanosheet hydrogen evolution reaction

Tunable polarization holographic gratings obtained by varying the ratio of intensities of the recording beams

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Photonics Research 2024年第4期12卷 749-754页

作者： HONG CHEN ZIYAO lyu CHANGSHUN WANG State Key Laboratory of Advanced Optical Communication Systems and Networks School of Physics and AstronomyShanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Space-Ground Integrated Information Technology Beijing Institute of Satellite Information EngineeringBeijing 100095China

Polarization holography has been extensively applied in many fields, such as optical science, metrology, and biochemistry, due to its property of polarization modulation. However, the modulated polarization state of diffracted light corresponds strictly to that of incident light one by one. Here, a kind of tunable polarization holographic grating has been designed in terms of Jones matrices, and intensity-based polarization manipulation has been realized experimentally. The proposed tunable polarization holographic grating is recorded on an azobenzene liquid-crystalline film by a pair of coherent light beams with orthogonal polarization states and asymmetrically controlled intensities. It is found that the diffracted light can be actively manipulated from linearly to circularly polarized based on the light intensity of the recording holographic field when the polarization state of incident light keeps constant. Our work could enrich the field of light manipulation and holography.

关键词： holographic recording Polarization

Preparation and performance improvement of a dual-component microcapsule self-healing system for silicone rubber insulating material

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High Voltage 2024年第2期9卷 453-465页

作者： mingzhe Li Bin Cao Fanghui Yin Hongwei Mei Liming Wang Engineering Laboratory of Power Equipment Reliability in Complicated Coastal Environments Tsinghua Shenzhen International Graduate SchoolTsinghua UniversityShenzhenChina

A key factor limiting the development of silicone rubber insulating materials is their short service life in harsh operating *** establishment of a self-healing system is desired to improve the long-term operational performance of silicone rubber and effectively extend its service *** this study,poly(urea-formaldehyde)microcapsules containing polydimethylsiloxane healing agents are prepared and a dual-component microcapsule self-healing system for silicone rubber material is established and *** addition,the key factors affecting the self-healing performance(such as microcapsule size,rupture rate,and microcapsule doping amount)are *** is found that when SYLGARDTM 184 is used as the healing agent and matrix,with a 4:6(A:B)doping ratio of dual-component microcapsules and 20 phr doping amount,the self-healing efficiency is approximately 51%.Furthermore,increasing the microcapsule rupture rate and the interface strength between the healing agent and the matrix can effectively improve the self-healing *** relationships between key factors and self-healing performance are theoretically *** on the relationships,the microcapsule self-healing system can be appropriately *** results of this paper can provide a reference for the development of long-life silicone rubber insulating materials.

关键词： service rubber performance

Pre-combustion mercury removal with co-production of hydrogen via coal electrolysis

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Journal of Environmental Sciences 2024年第2期136卷 382-389页

作者： Xiang lyu Runming Tao Tianyu Zhang Chemical and Biomolecular Engineering Department Ohio University165 Stocker CenterAthensOH45701USA Electrification and Energy Infrastructures Division Oak Ridge National LaboratoryOak RidgeTN37831USA Beijing Key Lab for Source Control Technology of Water Pollution College of Environmental Science and EngineeringBeijing Forestry UniversityBeijing 100083China Engineering Research Center for Water Pollution Source Control&Eco-remediation College of Environmental Science and EngineeringBeijing Forestry UniversityBeijing 100083China

Pre-combustion mercury removal via coal electrolysis was performed and investigated on a bench-scale coal electrolytic cell(CEC)systemically,and factorial design was used to determine the effect of different operating conditions(coal particle size,operating temperature,operating cell voltage,and flow rate of slurry)on the percentage of mercury removal,percentage of ash removal,and dry heating value *** results showed that the operating cell voltage,as well as the interaction between operating cell voltage and coal particle size,are significant factors in the percentage of mercury *** is no significant factor in the percentage of ash removal and the dry heating value change,but the coal could be purified while keeping the dry heating value almost constant after electrolysis.A co-product of hydrogen could be produced during coal electrolysis with 50%lower energy consumption compared with water ***,a mechanism for mercury removal in coal was *** facts indicate that coal electrolysis is a promising method for precombustion mercury removal.

关键词： Pre-combustion mercury removal Coal electrolysis Ash removal Dry heating value Hydrogen production

基于16S rDNA高通量测序技术分析限制基础饲粮补饲水培大麦苗对籽鹅肠道菌群的影响

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中国畜牧兽医 2024年第5期51卷 1921-1930页

作者：董佳强马志刚霍明东王志强黄宇翔邹跃郭文凯吕明哲张红杨昊天杨坤魏念冬周景明韩永胜江波涛陈志峰黑龙江省农业科学院畜牧兽医分院齐齐哈尔161005

【目的】本试验旨在通过16S rDNA高通量测序技术分析限制基础饲粮补饲水培大麦苗对籽鹅肠道菌群的影响。【方法】试验选取28日龄籽鹅160只,随机分为4组,每组4个重复,每个重复10只鹅。A组籽鹅自由采食基础饲粮,B、C和D组籽鹅分别以A组采... 详细信息

【目的】本试验旨在通过16S rDNA高通量测序技术分析限制基础饲粮补饲水培大麦苗对籽鹅肠道菌群的影响。【方法】试验选取28日龄籽鹅160只,随机分为4组,每组4个重复,每个重复10只鹅。A组籽鹅自由采食基础饲粮,B、C和D组籽鹅分别以A组采食量的85%、72.5%和60%饲喂基础饲粮,自由采食水培大麦苗。试验期42 d。70日龄时,每个重复抽取2只籽鹅屠宰后取空肠和回肠混合内容物及盲肠内容物,通过Illumina MiSeq测序平台进行高通量测序及生物信息学分析。【结果】①籽鹅肠道微生物Alpha多样性指数和Beta多样性分析结果在各组间均无显著性差异(P>0.05)。②4组籽鹅肠道微生物共有4个优势菌门(相对丰度>1%):厚壁菌门、变形菌门、拟杆菌门和放线菌门;共有7个优势菌属:肠球菌属、假单胞菌属、拟杆菌属、罕见小球菌属、颤螺菌属、栖粪杆菌属和螺杆菌属。D组放线菌门的相对丰度显著低于A组(P<0.05);B、C和D组螺旋体门、梭杆菌门、棒杆菌属、葡萄球菌属和气球菌属的相对丰度均显著低于A组,肠球菌属的相对丰度显著高于A组(P<0.05)。③经LEfSe分析发现,A组籽鹅肠道微生物有标志物种4个:放线菌门、栖水菌属、乳杆菌属和乳杆菌科;B组有标志物种3个:叶绿体纲、链形植物目和间孢囊菌科;C组有标志物种11个:黄色单胞菌科、黄色单胞菌目、慢生根瘤菌科、草酸杆菌科、伯克氏菌目、劳尔氏菌属、β-变形菌纲、TM7菌门、TM7_3菌纲、Rs_045菌科和I025菌目;D组籽鹅肠道未发现标志物种。【结论】在本试验条件下,限制基础饲粮采食补饲水培大麦苗对籽鹅肠道微生物菌群多样性影响较小,但会影响菌群相对丰度,并能抑制部分致病菌生长、改善肠道健康状态;但基础饲粮供给比例过低可能引起菌群失衡。

关键词：籽鹅水培大麦苗肠道菌群 16S rDNA