Article
Multidisciplinary Sciences
Yang Chen, Fangyan Zhu, Jiantao Leng, Tianquan Ying, Jin- Wu Jiang, Quan Zhou, Tienchong Chang, Wanlin Guo, Huajian Gao
Summary: This study reports a mechanism capable of controllably driving directed motion of any nanoo-bjects in both solid and liquid forms. The driving force originates from the difference in atomic fluctuations of the substrate behind and ahead of the object, and it can be flexibly tuned based on the amplitude and frequency of the substrate.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2023)
Article
Mechanics
Yichang Chen, Jiantao Leng, Zhengrong Guo, Yingyan Zhang, Tienchong Chang
Summary: The study proposes a method for achieving nanoscale continuous directional motion in cyclic thermal fields using a double-walled system, where manipulating the heating regions of an outer BN/C heterojunction tube allows for easy realization of continuous motion of an inner carbon nanotube (CNT). This mechanism, driven by asymmetric thermal gradient forces and interlayer attraction forces, may be useful in designing novel devices for energy conversion and directional transportation.
JOURNAL OF APPLIED MECHANICS-TRANSACTIONS OF THE ASME
(2021)
Article
Biotechnology & Applied Microbiology
Yuanchun Zhu, Yanan Feng, Fangchao Huang, Yapeng Li, Wenjing Wang, Xueqiang Wang, Xiangyang Cao, Zhijie Zhang
Summary: This study investigated the acute and prolonged effects of static stretching on the stiffness of specific regions of the knee extensor mechanism and knee flexion range of motion. The results demonstrated that static stretching intervention can increase knee flexion range of motion and temporarily reduce stiffness of specific regions of the knee extensor mechanism.
FRONTIERS IN BIOENGINEERING AND BIOTECHNOLOGY
(2022)
Article
Nanoscience & Nanotechnology
O. Florez, G. Arregui, M. Albrechtsen, R. C. Ng, J. Gomis-Bresco, S. Stobbe, C. M. Sotomayor-Torres, P. D. Garcia
Summary: Nanopatterned materials have the capability to control mechanical vibrations and enable the suppression of vibrations and propagation of hypersonic guided modes at room temperature. The structuring of solids to possess a phononic stop band can eliminate thermal vibrations. Experimental results demonstrate that the shamrock crystal geometry on a nanostructured silicon membrane can efficiently manipulate phonons, with potential applications in optomechanics and signal processing transduction.
NATURE NANOTECHNOLOGY
(2022)
Article
Physics, Fluids & Plasmas
Amir Nourhani, David Saintillan
Summary: The study predicts the emergence of large-scale polar order and spontaneous directional flows in a new class of particles that interact via passive repulsion between off-center sites. The coupling of active motion with passive torque leads to hybrid active-passive interactions responsible for a macroscopic phase transition, driving the system from an isotropic state to a polar-aligned state.
Article
Optics
Mohsen Samadi, Pooya Alibeigloo, Abolfazl Aqhili, Mohammad Ali Khosravi, Farahnaz Saeidi, Shoaib Vasini, Mostafa Ghorbanzadeh, Sara Darbari, Mohammad Kazem Moravvej-Farshi
Summary: Plasmonic tweezers are indispensable tools for manipulating micro and nano-objects with high precision, utilizing surface plasmon technology to trap particles beyond the diffraction limit. Trapping-potential landscape can be reconfigured by designing plasmonic nanostructures.
OPTICS AND LASERS IN ENGINEERING
(2022)
Article
Chemistry, Multidisciplinary
Aaron Gerwien, Frederik Gnannt, Peter Mayer, Henry Dube
Summary: This paper presents a light-fuelled molecular gearing system that allows for precise control and direction change of motion. Compared to passive thermally activated gears, this system demonstrates superior efficiency and flexibility, offering potential for future mechanical nano-systems.
Article
Nanoscience & Nanotechnology
Hai Lin, Te Wen, Jinglin Tang, Lulu Ye, Guanyu Zhang, Weidong Zhang, Ying Gu, Qihuang Gong, Guowei Lu
Summary: Efficient manipulation of the emission direction of a chiral nanoscale light source is achieved using a scheme based on gap plasmons. Highly directional emission of chiral light sources is realized using a gap plasmon mode formed by a gold nanorod and a silver nanowire. The emission direction can be controlled by modifying the configuration of the structure. Additionally, a strong local field enhancement allows for highly enhanced emission rates within the nanogap. This manipulation scheme provides a way for chiral valleytronics and integrated photonics.
Article
Engineering, Mechanical
Hongye Ma, Ke Wang, Haifeng Zhao, Ruinan Mu, Bo Yan
Summary: This paper presents an innovative, reusable, and self-recoverable metastructure (RSRMS) with tetrahedral motif unit cells (TMUCs) for tri-directional energy dissipation. Through numerical simulations, finite element analysis, and experimental investigations, it is found that RSRMS can effectively dissipate energy through snap-through induced hysteretic force-displacement behavior and elastic deformation, providing potential advantages in applications requiring repetitive energy dissipation.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2022)
Article
Engineering, Mechanical
Yifei Yang, Yifan Lu, Rongru Zhang, Honghao Yue
Summary: This study developed a novel, compact and integrated rotating joint with variable stiffness, capable of real-time control of rotational stiffness and motion. By changing the arm length of cantilever leaf springs, a stiffness-adjusting module with superior mechanical properties was proposed. A universal mechanical model of stiffness that adapts to a wide range of deformation was also presented. The stiffness of the joint was adjusted by reverse calculation of the motor's rotating angle, and a nonlinear Proportion-Integral-Derivative method based on a Genetic Algorithm was proposed for motion control. Experimental results demonstrated that the proposed joint has a large bearing capacity and a wide range of stiffness adjustment, and can achieve good motion control performance.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2023)
Article
Chemistry, Multidisciplinary
Aaron Gerwien, Frederik Gnannt, Peter Mayer, Henry Dube
Summary: This article presents a light-fuelled molecular gearing system that enables precise motion transmission and direction change, providing an important technological foundation for future mechanical nano-systems.
Article
Chemistry, Multidisciplinary
Patrick Commins, Marieh B. B. Al-Handawi, Rachid Rezgui, Liang Li, Mark McNamara, Pance Naumov
Summary: We demonstrate a method based on gradually widening surface microchannels to enable the autonomous and bidirectional transduction of condensed water on a slowly subliming hexachlorobenzene crystal. The topological changes on the crystal surface and water exchange with the gas phase allow the condensed water droplets to migrate and transport silver particles and other particulate matter. The velocity of the particles depends on the sublimation rate of the crystal and the relative humidity of the environment.
Article
Engineering, Electrical & Electronic
Zhundong Li, Fengming Hu, Zhiming Chen, Jingcheng Huang, Guoning Chen, Runbo Chen, Minmin Wei, Kete Lao, Jiajia Hu, Jintao Zheng, Lvfei Wang, Yuan Yao, Xiaoyan Hu, Baowen Liang, Min Yang, Xihong Lu, Jinxiu Wen, Jianyi Luo
Summary: This article introduces a method and principle of manufacturing directional bending sensors using fiber-junction structure models, which allows for measurement of bending angle and recognition of direction through a theoretical expression. This method is simple and practical, with directional recognition capability.
NPJ FLEXIBLE ELECTRONICS
(2021)
Article
Multidisciplinary Sciences
Eva Bertosin, Christopher M. Maffeo, Thomas Drexler, Maximilian N. Honemann, Aleksei Aksimentiev, Hendrik Dietz
Summary: The study reports a molecular mechanism that converts chemical energy into mechanical work, using DNA origami to design a rotating nanomechanism that transforms rotary motion into large-scale structural transitions in the surrounding stator.
NATURE COMMUNICATIONS
(2021)
Article
Engineering, Multidisciplinary
Renzhen Chen, Xiaopeng Li, Jing Tian, Zemin Yang, Jinchi Xu
Summary: This paper presents the design and structure of the proposed variable stiffness vibration isolation joint (VSJ), discussing its potential applications in engineering. Experimental results verify the effectiveness of its adjustable stiffness and vibration isolation performance in the vertical direction.
APPLIED MATHEMATICAL MODELLING
(2022)
Article
Engineering, Chemical
Michele Ciavarella, Shubo Zhang, Huajian Gao, Gabriele Cricri
Summary: Experimental studies on peeling in viscoelastic materials have been conducted for many years, with a focus on 90 or 180 degrees angle. The classical Rivlin energy balance equation is commonly used to determine the velocity-dependent work of fracture. However, the behavior of this velocity dependence remains unexplained and existing models fail to account for it.
JOURNAL OF ADHESION SCIENCE AND TECHNOLOGY
(2023)
Article
Materials Science, Multidisciplinary
Christos E. Athanasiou, Xing Liu, Boyu Zhang, Truong Cai, Cristina Ramirez, Nitin P. Padture, Jun Lou, Brian W. Sheldon, Huajian Gao
Summary: Measuring fracture toughness of materials at small scales remains challenging, but the recently developed indentation pillar-splitting method shows promise in improving flexibility for such measurements at the microscale. However, the underlying mechanism of the fracture instability observed in this method is still unclear. In this study, in situ experiments and high-fidelity simulations were combined to provide a comprehensive description of the fracture instability in indentation pillar-splitting. Additionally, a machine-learning-based solution for predicting the critical indentation load of fracture instability was established for broader use of this method by the community.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2023)
Article
Nanoscience & Nanotechnology
Zhenghong Dai, Meaghan C. Doyle, Xing Liu, Mingyu Hu, Qizhong Wang, Christos E. Athanasiou, Yucheng Liu, Brian W. Sheldon, Huajian Gao, Shengzhong (Frank) Liu, Nitin P. Padture
Summary: In this study, the mechanical properties, including elasticity, plasticity, fracture, and creep, relevant to the mechanical reliability of perovskite solar cells (PSCs), were systematically investigated. High-quality single-crystals of commonly studied metal-halide perovskites (MHPs) were fabricated and studied. The results provide important parameters for future mechanical behavior and reliability analysis of MHPs and PSCs.
SCRIPTA MATERIALIA
(2023)
Article
Multidisciplinary Sciences
Xiao Guo, Xinyu Dong, Guijin Zou, Huajian Gao, Wei Zhai
Summary: We have successfully fabricated a strong and tough hydrogel with architected multiscale hierarchical structures using a freeze-casting-assisted solution substitution strategy. The key factors contributing to its toughness are the microscale anisotropic honeycomb-structured fiber walls and matrix, hydrogen bond-enhanced fibers with nanocrystalline domains, and cross-linked strong polyvinyl alcohol chains with chain-connecting ionic bonds. This study provides insights into the structure-performance mechanisms of tough hierarchically structured hydrogels and offers inspiration for advanced design strategies for other promising hierarchical materials.
Article
Chemistry, Multidisciplinary
Yingchao Zhang, Yurong Tan, Jiazheng Lao, Huajian Gao, Jing Yu
Summary: Hydrogels are promising materials for flexible electronics due to their unique properties. This perspective provides an overview of their development in this field, focusing on mechanical properties, interfacial adhesion, and conductivity. Design principles for high-performance hydrogels and potential applications in healthcare are discussed, along with remaining challenges. Considering hydrogel-cell interactions and dynamic properties is important for future research, and continued investment in research and development is necessary to overcome these challenges.
Article
Chemistry, Multidisciplinary
Huizhong Bai, Guijin Zou, Hongwei Bao, Suzhi Li, Fei Ma, Huajian Gao
Summary: The friction behavior of multilayer graphene-coated substrates is not solely determined by the Moire superlattices, but also by the competition between interfacial Moire superlattices interactions and the out-of-plane deformation of the surface. Thicker graphene coatings exhibit lower intrinsic friction and higher sliding stability due to the spatial distribution of the atomic contact distance.
Article
Multidisciplinary Sciences
Changhong Linghu, Yangchengyi Liu, Yee Yuan Tan, Jun Heng Marcus Sing, Yuxuan Tang, Aiwu Zhou, Xiufeng Wang, Dong Li, Huajian Gao, K. Jimmy Hsia
Summary: Using shape-memory polymers (SMPs), researchers have developed adhesive materials that can overcome the challenges of adhesion on rough surfaces. The adhesive exhibits extraordinary strength in the rubbery state and can easily detach in the glassy state, making it highly switchable. This advancement has the potential to enhance the capabilities of smart adhesives in various applications.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2023)
Article
Multidisciplinary Sciences
Chao Shi, Guijin Zou, Zeming Wu, Meng Wang, Xinyun Zhang, Huajian Gao, Xin Yi
Summary: Combining theoretical modeling and molecular dynamics simulations, the study investigates the packing of a flexible filament inside a vesicle and explores the effects of filament stiffness, size, and osmotic pressure on the vesicle morphology. The results reveal various morphological transitions and establish phase diagrams predicting shape and symmetry transitions. The organization of filaments or nanotube rings inside vesicles, liposomes, or cells is discussed, providing insights into cell shaping, cellular stability, and the design of artificial cells and biohybrid microrobots.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2023)
Article
Chemistry, Multidisciplinary
Yujia Wang, Fan Xu, Huajian Gao, Xiaoyan Li
Summary: This study introduces a new type of hierarchical lattice, called ISO-COP, which exhibits elastic isotropy and enhanced moduli. The fabricated ISO-COP microlattices demonstrate superior strength compared with existing fractal octet-truss hierarchical lattices.
Article
Materials Science, Multidisciplinary
Anne Marie Z. Tan, Zhi Li, Huajian Gao
Summary: In recent years, complex concentrated alloys (CCAs) have attracted attention for their excellent mechanical properties. However, the effect of chemical inhomogeneity on dislocation nucleation and incipient plasticity in CCAs is not well understood. In this study, a statistical model combining elasticity theory and statistical modeling was used to investigate incipient plasticity in CCAs. The model was validated by molecular dynamics simulations and revealed the influence of spatial variation in the local properties on the nanoindentation-induced plasticity in CCAs.
PHYSICAL REVIEW MATERIALS
(2023)
Article
Mechanics
Yingchao Zhang, Yinji Ma, Jing Yu, Huajian Gao
Summary: Snap-through buckling of bistable structures can be triggered and controlled through deformation caused by an externally applied magnetic field in hard magnetic elastica (HME). The key parameters in the design of HME are the remanent magnetization density after premagnetization and the external magnetic field. Experimental results show that optimal positions of a single magnetization interface and directions of a uniform actuation field can reduce the required actuation field for snapping nearly by half in pre-buckled beams with two-ends fixed.
INTERNATIONAL JOURNAL OF SOLIDS AND STRUCTURES
(2023)
Article
Chemistry, Multidisciplinary
Wenxin Zhang, Zhi Li, Ruoqi Dang, Thomas T. Tran, Rebecca A. Gallivan, Huajian Gao, Julia R. Greer
Summary: This study investigates the mechanical size effects in nanosized metals, focusing on the hierarchical microstructures and their impact on mechanical properties. By producing nickel nanopillars and conducting compression experiments, the researchers discover the influence of hierarchical microstructures on the mechanical response of nanosized metals.
Article
Chemistry, Multidisciplinary
Zhuo Chang, Jing Zhang, Yilun Liu, Huajian Gao, Guang-Kui Xu
Summary: In this study, the rheological responses of cardiac tissues at different stages of myocardial infarction (MI) were investigated using atomic force microscopy-based microrheology. It was found that all cardiac tissues exhibited a universal two-stage power-law rheological behavior at different time scales. The power-law exponents discovered in the experiment can capture an inconspicuous initial rheological change, making them suitable as markers for early-stage MI diagnosis.
Article
Multidisciplinary Sciences
Yang Chen, Fangyan Zhu, Jiantao Leng, Tianquan Ying, Jin- Wu Jiang, Quan Zhou, Tienchong Chang, Wanlin Guo, Huajian Gao
Summary: This study reports a mechanism capable of controllably driving directed motion of any nanoo-bjects in both solid and liquid forms. The driving force originates from the difference in atomic fluctuations of the substrate behind and ahead of the object, and it can be flexibly tuned based on the amplitude and frequency of the substrate.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2023)
Review
Materials Science, Multidisciplinary
Weiming Ji, Runhua Zhou, Priyanka Vivegananthan, Mao See Wu, Huajian Gao, Kun Zhou
Summary: This review critically evaluates the latest research on gradient-structured metals and alloys, summarizing their fabrication techniques, strengthening mechanisms, mechanical properties, and discussing potential applications and prospects.
PROGRESS IN MATERIALS SCIENCE
(2023)