Article
Engineering, Manufacturing
Ziqi Gao, Jun Yin, Peng Liu, Qi Li, Runan Zhang, Huayong Yang, Hongzhao Zhou
Summary: To mimic natural tissue, multi-material bioprinting is commonly used to construct tissue models in vitro. The current sequential multi-material embedded printing method has a trade-off between structural integrity and printing precision. We propose a simultaneous multi-material embedded printing method that can print firmly attached and high-precision multilayer structures. This method minimizes uncontrolled squeezing and contamination, and offers better structural integrity than conventional sequential printing methods, making it a powerful tool for personalized medicine.
INTERNATIONAL JOURNAL OF EXTREME MANUFACTURING
(2023)
Article
Materials Science, Multidisciplinary
Eva Baur, Matteo Hirsch, Esther Amstad
Summary: This study presents a method to introduce controllable open pores into hydrogels while maintaining their mechanical properties. The hydrogels are 3D printable and the pore size can be tuned from nanometers to centimeters. This work allows for size-selective infiltration of different substances at specific locations.
ADVANCED MATERIALS TECHNOLOGIES
(2023)
Article
Polymer Science
Tianzhou Hu, Zhengwei Cai, Ruixue Yin, Wenjun Zhang, Chunyan Bao, Linyong Zhu, Honbo Zhang
Summary: Biofabrication is essential for contemporary tissue engineering, with the primary challenge being the replication of both external organ geometries and internal structures simultaneously. This study addresses this problem by introducing a novel 3D printing strategy using a thermo-reversible supporting bath that can be easily removed. The technology is capable of printing hydrated materials with diverse crosslinked mechanisms and replicating the external geometry of native tissues and organs from computed tomography data. The study also demonstrates the ability to fabricate intricate capillary networks using a nozzle with a reduced line size due to the extra force exerted by the supporting bath.
Article
Chemistry, Multidisciplinary
Kun Peng Zhang, Yan Fei Liao, Bin Qiu, Yue Kun Zheng, Ling Ke Yu, Gong Han He, Qin Nan Chen, Dao Heng Sun
Summary: This research uses projection micro-stereolithography 3D printing technology and liquid metal filling method to manufacture conformal and 3D metamaterials, improving transmission properties of the metamaterial devices by optimizing filling channel layout and surface post-treatment process.
Review
Engineering, Multidisciplinary
Xin Ning Zhang, Qiang Zheng, Zi Liang Wu
Summary: This paper reviews the recent progress in 3D printing of tough hydrogels and their applications. It provides an overview of the advantages and requirements of tough hydrogel systems for specific 3D printing technologies, and summarizes the network structures, mechanical performances, toughening mechanisms, and representative applications of the printed tough hydrogels. It also discusses the recent advances in 4D printing of tough hydrogels as a prospective direction for soft actuators and robots.
COMPOSITES PART B-ENGINEERING
(2022)
Article
Chemistry, Multidisciplinary
Consuelo Rodriguez-Padilla, Enrique Cuan-Urquizo, Armando Roman-Flores, Jose L. Gordillo, Carlos Vazquez-Hurtado
Summary: In contrast to traditional 3D printing, conformal 3D printing enables structures to be created on non-planar surfaces, with a mathematical algorithm proposed to project printing trajectories onto such surfaces. The effectiveness of the algorithm is demonstrated through examples and comparisons with tessellated surfaces, showing that error depends on resolution rather than the algorithm itself.
APPLIED SCIENCES-BASEL
(2021)
Article
Engineering, Manufacturing
S. Barnes, L. Kirssin, E. Needham, E. Baharlou, D. E. Carr, J. Ma
Summary: This study investigates the feasibility of 3D printing soil structures that could support plant life. The results show that stand-alone soil structures can be successfully printed without additives using the extrusion method. By properly controlling the water content, the printed structures are capable of supporting germination and growth of plants. It is also found that the water retention abilities of the printed structures differ from potted soil of the same composition. The study demonstrates a fundamental difference in the soil-water characteristics of the extruded soils and correlates the drying characteristics with the ability of the soil to support plant growth in different soil textures.
ADDITIVE MANUFACTURING
(2022)
Article
Polymer Science
Sheila Maiz-Fernandez, Leyre Perez-alvarez, Unai Silvan, Jose Luis Vilas-Vilela, Senentxu Lanceros-Mendez
Summary: This study explores the limitations of hydrogel-based inks in 3D printing and successfully achieves direct 3D printing of chitosan structures using NaOH as a gelling media for biomedical and tissue engineering applications. The printed hydrogels exhibit good morphology, chemical interactions, swelling, and mechanical and rheological properties. The influence of printing parameters and cytocompatibility are also analyzed. In addition, the printed gels show electro-induced motion, highlighting their potential as soft actuators and active scaffolds.
Article
Chemistry, Multidisciplinary
Xiaoya Ding, Yunru Yu, Luoran Shang, Yuanjin Zhao
Summary: With the assistance of histidine, low-viscosity GO mixed polymer solutions can be prepared as printable inks through microfluidic 3D printing technique, forming hydrogel microfibers in histidine solutions. These hydrogel fibers support cell survival, exhibit excellent electrical conductivity, and can sense motion changes, offering a new option for the design and application of 3D printable aqueous GO inks in various fields.
Article
Chemistry, Multidisciplinary
Hamed Ramezani, Seyyed Mohammad Mirjamali, Yong He
Summary: This study used multiphysics simulation to predict the printability of chitosan hydrogel in extrusion-based 3D printing. The impact of different velocities and viscosities was investigated, and the model validation confirmed the high-quality printing outcomes. The results provide information for determining the optimum parameters for printing chitosan-based ink with high quality.
APPLIED SCIENCES-BASEL
(2022)
Article
Biochemistry & Molecular Biology
Rand Alkaissy, Michael Richard, Hayley Morris, Sarah Snelling, Henry Pinchbeck, Andrew Carr, Pierre-Alexis Mouthuy
Summary: Rotator cuff tendon tears are common injuries that often require surgical repair. A combination of electrospinning and 3D printing can be used to create biphasic scaffolds that mimic the interface and improve the outcomes of rotator cuff repair.
MACROMOLECULAR BIOSCIENCE
(2022)
Article
Chemistry, Multidisciplinary
Matteo Hirsch, Alvaro Charlet, Esther Amstad
Summary: Many soft natural tissues possess unique mechanical properties achieved through complex interactions between structure and composition. To address the lack of control in soft synthetic materials, a novel 3D printing approach called double network granular hydrogels (DNGHs) has been introduced. These DNGHs are stiff enough to support high tensile loads and significantly tougher than pure polymeric networks. This ink allows for the printing of strong and tough objects with high shape fidelity, opening up new possibilities for soft robotic applications.
ADVANCED FUNCTIONAL MATERIALS
(2021)
Article
Chemistry, Multidisciplinary
Ji Liu, James Garcia, Liam M. M. Leahy, Rijian Song, Daragh Mullarkey, Ban Fei, Adrian Dervan, Igor V. V. Shvets, Plamen Stamenov, Wenxin Wang, Fergal J. J. O'Brien, Jonathan N. N. Coleman, Valeria Nicolosi
Summary: Direct ink writing (DIW) is a viable 3D printing technology for custom production of functional conductive hydrogels. This study demonstrates a highly 3D printable PEDOT:PSS-based ink made from commercially accessible raw materials. The 3D-printed hydrogel exhibits high electrical conductivity, outstanding elasticity, stability in water, electromagnetic interference shielding, sensing capabilities, and biocompatibility, showing potential for implantable and tissue engineering applications. The fabrication strategy opens up new opportunities to create multifunctional hydrogels with custom features and expand the applications of hydrogel materials.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Review
Chemistry, Multidisciplinary
Gang Ge, Qian Wang, Yi-Zhou Zhang, Husam N. Alshareef, Xiaochen Dong
Summary: In the development of flexible electronics, particularly hydrogel-based stretchable ionotronic devices, researchers are exploring the potential of 3D printing for its excellent patterning capability and design complexity. Despite facing challenges in balancing printability, conductivity, and stretchability, this review offers guidelines on utilizing 3D printing to create high-performance devices, focusing on material considerations and printing quality. Various 3D printing methods for hydrogels and design principles are discussed, along with the potential applications in flexible sensors, soft robots, and other devices.
ADVANCED FUNCTIONAL MATERIALS
(2021)
Article
Multidisciplinary Sciences
Hongqiu Wei, Ming Lei, Ping Zhang, Jinsong Leng, Zijian Zheng, You Yu
Summary: The study demonstrates the successful preparation of tough conductive hydrogels using an orthogonal photochemistry-assisted printing technique, which features rapid, controllable chemical reactions and template-free fabrication of arbitrary structures.
NATURE COMMUNICATIONS
(2021)
Article
Chemistry, Multidisciplinary
Xiangyu Liang, Guangda Chen, Iek Man Lei, Pei Zhang, Zeyu Wang, Xingmei Chen, Mengze Lu, Jiajun Zhang, Zongbao Wang, Taolin Sun, Yang Lan, Ji Liu
Summary: By harnessing multi-length-scale structural hierarchy and using bidirectional freeze-casting and compression-annealing, a hierarchically structured hydrogel material has been developed. The engineered 2D lamellar structures, well-defined nanocrystalline domains, and robust interfacial interaction contribute to the hydrogel's high impact resistance, high water content, and superior softness, resulting in record-high ballistic energy absorption capability.
ADVANCED MATERIALS
(2023)
Article
Automation & Control Systems
Guangda Chen, Ruonan Xue, Chao Song, Dejun Liu, Letian Ren, Yanming Cheng
Summary: This paper proposes a double loop control strategy to address the XY platform driven by stepping motor. It utilizes a PID controller for speed loop and active disturbance rejection for position loop in order to improve traceability and disturbance rejection. Additionally, a deviation self-coupling compensation control strategy is introduced. Comparative experiments demonstrate the superiority of the proposed strategy.
MEASUREMENT & CONTROL
(2023)
Article
Chemistry, Multidisciplinary
Xiangyu Liang, Guangda Chen, Iek Man Lei, Pei Zhang, Zeyu Wang, Xingmei Chen, Mengze Lu, Jiajun Zhang, Zongbao Wang, Taolin Sun, Yang Lan, Ji Liu
ADVANCED MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Nannan Jian, Rui Guo, Lei Zuo, Yibo Sun, Yu Xue, Ji Liu, Kai Zhang
Summary: The production of natural materials involves bottom-up growth and adaptation to the environment, while synthetic materials are engineered and lack self-growing attributes. Replicating the self-growing characteristics of natural prototypes remains challenging. This study reports the fabrication of synthetic hydrogels with self-growing properties inspired by the self-growing behaviors of keratin proteins, broadening the potential applications of self-growing materials in actuation and soft robotics.
ADVANCED MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Jiajun Zhang, Lulu Wang, Yu Xue, Iek Man Lei, Xingmei Chen, Pei Zhang, Chengcheng Cai, Xiangyu Liang, Yi Lu, Ji Liu
Summary: Coating conventional metallic electrodes with conducting polymers enables the bioelectrodes to have desirable characteristics for bioelectronics. However, the fragile interface between the conducting polymer and the electrode limits their utility and reliability. In this study, a reliable strategy for seamlessly connecting conventional electrodes with conducting hydrogel coatings is established, which improves the long-term robustness of the interface. Through in vivo implantation in mouse models, stable electrophysiological recording is achieved with a robust conducting hydrogel-electrode interface. This design strategy addresses technical challenges in bioelectrode engineering and opens up new avenues for diagnostic brain-machine interfaces.
ADVANCED MATERIALS
(2023)
Article
Multidisciplinary Sciences
Yuxuan Sun, Liu Wang, Yangyang Ni, Huajian Zhang, Xiang Cui, Jiahao Li, Yinbo Zhu, Ji Liu, Shiwu Zhang, Yong Chen, Mujun Li
Summary: The authors present an in situ dual heating strategy for the rapid 3D printing of thermosets with complex structures and diverse rheological properties. This strategy combines the direct ink writing (DIW) technique and a heating-accelerated in situ gelation mechanism, allowing for the printing of various thermosets with viscosities spanning five orders of magnitude, printed height over 100 mm, and high resolution of 50 μm.
NATURE COMMUNICATIONS
(2023)
Review
Virology
Yong-Yu Gao, Qian Wang, Xiang-Yu Liang, Shuang Zhang, Di Bao, Han Zhao, Shao-Bai Li, Kai Wang, Gui-Xue Hu, Feng-Shan Gao
Summary: This article reviews recent progress in FCoV research, including the etiological characteristics, epidemiology, clinical symptoms and pathological changes, pathogenesis, and current diagnosis, prevention, and treatment methods. It is hoped that this review will provide a reference for further research on FCoV and other coronaviruses.
Article
Mathematics, Applied
Xiangyu Liang
Summary: In this article, we prove the minimality of the product of a 1-codimensional calibrated manifold and a paired calibrated set. This is motivated by the attempt to classify all possible singularities for Almgren minimal sets - Plateau's problem in the setting of sets. We prove the Almgren minimality for the product of two large classes of Almgren minimal sets - the class of 1-codimensional calibrated manifolds and the class of paired calibrated sets, by properly combining different topological conditions.
ADVANCES IN CALCULUS OF VARIATIONS
(2023)
Article
Energy & Fuels
Xintong Li, Jianwei Mi, Yiqun Zhang, Guangda Chen, Guanheng Fan, Dongxu Wang, Yingchun Du
Summary: This article enhances the power generation of a concentrated space solar power station (SSPS) by using current-injected total-cross-tied (TCT-CI) photovoltaic (PV) array. A mathematical model of the TCT-CI-connected PV array is established, and several common topologies and TCT-CI topology are simulated and analyzed. Comparative experiments on TCT and TCT-CI-connected PV arrays are conducted under non-uniform light intensity distribution. The results show that TCT-CI-connected PV arrays reduce the difficulty of MPPT, increase power generation, and are applicable for concentrated SSPS.
FRONTIERS IN ENERGY RESEARCH
(2023)
Article
Chemistry, Multidisciplinary
Yuxuan Sun, Liu Wang, Zhengqing Zhu, Xingxiang Li, Hong Sun, Yong Zhao, Chenhui Peng, Ji Liu, Shiwu Zhang, Mujun Li
Summary: This study reports a ferromagnetic liquid crystal elastomer (magLCE) ink that allows independent programming of nematic order and magnetization via a customized 3D-printing platform. The 3D-printed magLCE offers designable shape morphing under different stimuli, making it promising for applications in wireless soft robots and intelligent devices.
ADVANCED MATERIALS
(2023)
Article
Chemistry, Multidisciplinary
Yu Xue, Xingmei Chen, Fucheng Wang, Jingsen Lin, Ji Liu
Summary: Conducting polymer hydrogels are widely used as coatings for metallic electrodes to create mechanically compliant interfaces and reduce foreign body responses. However, concerns regarding fatigue crack propagation and delamination have limited their long-term viability. This study presents a method for achieving fatigue-resistant conducting polymer hydrogel coatings on metallic bioelectrodes by introducing nanocrystalline domains at the hydrogel-metal interface. The results show that this robust and biocompatible coating effectively reduces the required voltage for cardiac pacing and improves the long-term reliability of electric stimulation, indicating its potential for future bioelectronic interfaces.
ADVANCED MATERIALS
(2023)
Article
Robotics
Quecheng Qiu, Xuyang Zhang, Shunyi Yao, Yu'an Chen, Guangda Chen, Bei Hua, Jianmin Ji
Summary: Autonomous mobile robots are increasingly popular in various applications involving humans. Navigating efficiently and safely in crowded environments with diverse pedestrians is a challenge. Some pedestrians may actively avoid or ignore the robot, while others may try to block it. Identifying vulnerabilities of the navigation policy, situations where the robot may cause collisions, is also difficult. This study proposes a deep reinforcement learning approach to train a policy simulating the behavior of non-cooperators, effectively identifying vulnerabilities. The results show improved robustness of the navigation policy.
IEEE ROBOTICS AND AUTOMATION LETTERS
(2023)