Organisms have evolved a strain limiting mechanism,reflected as a non-linear elastic constitutive,to prevent large deformations from threatening soft tissue integrity.Compared with linear elastic substrates,the wrinkl...Organisms have evolved a strain limiting mechanism,reflected as a non-linear elastic constitutive,to prevent large deformations from threatening soft tissue integrity.Compared with linear elastic substrates,the wrinkle of films on non-linear elastic substrates has received less attention.In this article,a unique wrinkle evolution of the film-substrate system with a J-shaped non-linear stress-strain relation is reported.The result shows that a concave hexagonal array pattern is formed with the shrinkage strain of the film-substrate systems developing.As the interconnection of hexagonal arrays,a unit cell ridge network appears with properties such as chirality and helix.The subparagraph maze pattern formed with high compression is mainly composed of special single-cell ridge networks such as spiral single cores,chiral double cores,and combined multi-cores.This evolutionary model is highly consistent with the results of experiments,and it also predicts wrinkle morphology that has not yet been reported.These findings can serve as a novel explanation for the surface wrinkle of biological soft tissue,as well as provide references for the preparation of artificial biomaterials and programmable soft matter.展开更多
Quantitative investigation on mechanical characteristics of cardiac myocytes has important physiological significance. Based on elastic substrate technique, this paper develops a set of algorithms for high-efficiency ...Quantitative investigation on mechanical characteristics of cardiac myocytes has important physiological significance. Based on elastic substrate technique, this paper develops a set of algorithms for high-efficiency cellular traction recovery. By applying a gradient-based digital image correlation method to track randomly distributed fluorescence microbeads on the deformed substrate induced by single cardiac myocyte, high-resolution substrate displacement field can readily be obtained. By using a numerical algorithm based on the integral Boussinesq solution, cell-substrate tractions are reconstructed in a stable and reliable manner. Finally, spatiotemporal dynamics of a single cardiac myocyte is investigated as it adheres to a polyacrylamide elastic substrate.展开更多
Considering the adhesive effect and geometric nonlinearity, the adhesive contact between an elastic substrate and a clamped miniature circular plate with two different central rigid bumps under the action of uniform t...Considering the adhesive effect and geometric nonlinearity, the adhesive contact between an elastic substrate and a clamped miniature circular plate with two different central rigid bumps under the action of uniform transverse pressure and in-plane tensile force in the radial direction was analyzed. And an analytical solution is presented by using the perturbation method. The relation of surface adhesive energies with critical load to detach the contacted surfaces is obtained. In the numerical results, the effects of adhesive energy, in-plane tensile force, rigid bump size and contact radius on the critical load are discussed, and the relation of critical contact radius with the gap between the central rigid bump and the substrate for different adhesive energies is investigated.展开更多
This study presents a scheme for the identification and trimming of the first three harmonics of mass defects in micro hemispherical resonators(MHRs),aiming to refine their mass balancing techniques.Given the manufact...This study presents a scheme for the identification and trimming of the first three harmonics of mass defects in micro hemispherical resonators(MHRs),aiming to refine their mass balancing techniques.Given the manufacturing and structural uniqueness of MHRs,a multimodal elastic electrode substrate is designed to respond to the first three harmonics.Configured as cantilever beams with a load platform,this substrate forms an identification assembly with the MHR.The radial eccentric forces generated by the 1st and 3rd harmonics in the MHR can excite the swing modes of the assembly,while the axial force generated by the 2nd harmonic can induce axial mode vibrations along the Z-axis.A method is proposed to decompose the vibration information of the elastic electrode substrate into doublecycle,single-cycle,and offset components under the N=2 modes,enabling the extraction of swing mode and Z-axis translational mode response signals and the retro-calculation of the first three harmonics.Finite element simulation,based on a model of the identification assembly,validates the proposed scheme by simulating the identification and trimming process.Subsequently,an identification assembly sample is fabricated and subjected to identification and trimming of the first three harmonics using a laser vibrometer and femtosecond laser ablation process.After multiple iterations,the first three harmonics are reduced by 92.8%,89.3%,and 75.5%,respectively,effectively suppressing the swing modes and axial translation modes induced by unbalanced mass.展开更多
With the rapid development of wearable smart devices,many researchershave carried out in-depth research on the stretchable electrodes.As one of the corecomponents for electronics,the electrode mainly transfers the ele...With the rapid development of wearable smart devices,many researchershave carried out in-depth research on the stretchable electrodes.As one of the corecomponents for electronics,the electrode mainly transfers the electrons,which plays animportant role in driving the various electrical devices.The key to the research for thestretchable electrode is to maintain the excellent electrical properties or exhibit theregular conductive change when subjected to large tensile deformation.This articleoutlines the recent progress of stretchable electrodes and gives a comprehensiveintroduction to the structures,materials,and applications,including supercapacitors,lithium-ion batteries,organic light-emitting diodes,smart sensors,and heaters.Theperformance comparison of various stretchable electrodes was proposed to clearly showthe development challenges in this field.We hope that it can provide a meaningfulreference for realizing more sensitive,smart,and low-cost wearable electrical devices inthe near future.展开更多
基金This work was supported by the Youth Project of Hunan Provincial Department of Education(Grant No.22B0334)the Bridge and Tunnel Engineering Innovation Project of Changsha University of Science&Technology(Grant No.11ZDXK11)and the Practical Innovation and Entrepreneurship Capacity Improvement Plan of Changsha University of Science and Technology(Grant No.CLSJCX23029).
文摘Organisms have evolved a strain limiting mechanism,reflected as a non-linear elastic constitutive,to prevent large deformations from threatening soft tissue integrity.Compared with linear elastic substrates,the wrinkle of films on non-linear elastic substrates has received less attention.In this article,a unique wrinkle evolution of the film-substrate system with a J-shaped non-linear stress-strain relation is reported.The result shows that a concave hexagonal array pattern is formed with the shrinkage strain of the film-substrate systems developing.As the interconnection of hexagonal arrays,a unit cell ridge network appears with properties such as chirality and helix.The subparagraph maze pattern formed with high compression is mainly composed of special single-cell ridge networks such as spiral single cores,chiral double cores,and combined multi-cores.This evolutionary model is highly consistent with the results of experiments,and it also predicts wrinkle morphology that has not yet been reported.These findings can serve as a novel explanation for the surface wrinkle of biological soft tissue,as well as provide references for the preparation of artificial biomaterials and programmable soft matter.
基金supported by the National Basic Research Program (Grant No2007CB935602)the National Natural Science Foundation of China (Grant Nos90607004,10672005 and 10872008)
文摘Quantitative investigation on mechanical characteristics of cardiac myocytes has important physiological significance. Based on elastic substrate technique, this paper develops a set of algorithms for high-efficiency cellular traction recovery. By applying a gradient-based digital image correlation method to track randomly distributed fluorescence microbeads on the deformed substrate induced by single cardiac myocyte, high-resolution substrate displacement field can readily be obtained. By using a numerical algorithm based on the integral Boussinesq solution, cell-substrate tractions are reconstructed in a stable and reliable manner. Finally, spatiotemporal dynamics of a single cardiac myocyte is investigated as it adheres to a polyacrylamide elastic substrate.
基金Project supported by the National Natural Science Foundation of China (No. 10572049).
文摘Considering the adhesive effect and geometric nonlinearity, the adhesive contact between an elastic substrate and a clamped miniature circular plate with two different central rigid bumps under the action of uniform transverse pressure and in-plane tensile force in the radial direction was analyzed. And an analytical solution is presented by using the perturbation method. The relation of surface adhesive energies with critical load to detach the contacted surfaces is obtained. In the numerical results, the effects of adhesive energy, in-plane tensile force, rigid bump size and contact radius on the critical load are discussed, and the relation of critical contact radius with the gap between the central rigid bump and the substrate for different adhesive energies is investigated.
基金supported by the National Natural Science Foundation of China(62204261,51935013 and 52075540).
文摘This study presents a scheme for the identification and trimming of the first three harmonics of mass defects in micro hemispherical resonators(MHRs),aiming to refine their mass balancing techniques.Given the manufacturing and structural uniqueness of MHRs,a multimodal elastic electrode substrate is designed to respond to the first three harmonics.Configured as cantilever beams with a load platform,this substrate forms an identification assembly with the MHR.The radial eccentric forces generated by the 1st and 3rd harmonics in the MHR can excite the swing modes of the assembly,while the axial force generated by the 2nd harmonic can induce axial mode vibrations along the Z-axis.A method is proposed to decompose the vibration information of the elastic electrode substrate into doublecycle,single-cycle,and offset components under the N=2 modes,enabling the extraction of swing mode and Z-axis translational mode response signals and the retro-calculation of the first three harmonics.Finite element simulation,based on a model of the identification assembly,validates the proposed scheme by simulating the identification and trimming process.Subsequently,an identification assembly sample is fabricated and subjected to identification and trimming of the first three harmonics using a laser vibrometer and femtosecond laser ablation process.After multiple iterations,the first three harmonics are reduced by 92.8%,89.3%,and 75.5%,respectively,effectively suppressing the swing modes and axial translation modes induced by unbalanced mass.
基金supported by the Natural ScienceFoundation of Jilin Province(20200201070JC)the National NaturalScience Foundation of China(Grant No.21662038).
文摘With the rapid development of wearable smart devices,many researchershave carried out in-depth research on the stretchable electrodes.As one of the corecomponents for electronics,the electrode mainly transfers the electrons,which plays animportant role in driving the various electrical devices.The key to the research for thestretchable electrode is to maintain the excellent electrical properties or exhibit theregular conductive change when subjected to large tensile deformation.This articleoutlines the recent progress of stretchable electrodes and gives a comprehensiveintroduction to the structures,materials,and applications,including supercapacitors,lithium-ion batteries,organic light-emitting diodes,smart sensors,and heaters.Theperformance comparison of various stretchable electrodes was proposed to clearly showthe development challenges in this field.We hope that it can provide a meaningfulreference for realizing more sensitive,smart,and low-cost wearable electrical devices inthe near future.
