SENSORS
·
2019
·Vol. 19
·期 11
·2442
·
IF 3.031
Jianpeng Zhang,Yuhang Li,Yufeng Xing
Epidermal electronic sensors (EESs) possess great advantages in the real-time and enduring monitoring of human vital information compared to the traditional medical device for intimately making contact with human skin. Skin strain is a significant and effective routine to monitor motion, heart rate, wrist pulse, and skin growth in wound healing. In this paper, a novel skin sensor combined with a ternary conductive nanocomposite (Carbon black (CB)/Decamethylcyclopentasiloxane (D5)/Silbione) and a two-stage serpentine connector is designed and fabricated to monitor skin strain. The ultrasoft (~2 kPa) and adhesive properties of the ternary conductive nanocomposite ensure the capacity of the EES to intimately couple with human skin in order to improve accuracy with a relative error of 3.39% at strain 50% as well as a large strain range (0~50%) and gauge factor (GF ~2.5). The millimeter scale EES (~5 mm × 1 mm × 100 μm), based on the micro-nano fabrication technique, consisted of a two-stage serpentine connector and screen print of the ternary conductive nanocomposite. EESs with high comprehensive performance (electrical and mechanical properties) are fabricated to confirm the analytical results and monitor the motion of a human hand. The good agreement between experimental and analytical results paves the way for bettering monitoring of skin growth during wound healing in order to avoid necrosis and scarring. This EES in monitoring the motion of a human exhibit presents a promising application for assisting prosthetic movement.Keywords:epidermal electronic sensors;skin strain;high accuracy;millimeter scale
研究领域:
生物医学工程
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Applied Materials Today
·
2023
·
IF 8.3
Xiaoyu Li,Fu Zhao,Weibin Rong,Dongjie Li,Hui Xie
The small-scale robots for targeted drug delivery are gradually attracting great interest, and increasing the residence time of robots in targeted areas is conducive to increasing bioavailability. A drug-loaded magnetic millimetre-scale robot that can bond to colonic mucosa has been developed. The main body of the robot is composed of two approximately rectangular Poly (lactic acid) (PLA) sheets perpendicular to each other. The magnetic disk and the drug-loaded adhesive film are symmetrically distributed at the tail sheet. The robot has two ways to move: swimming and rolling. A high-frequency-rotating magnetic field can drive it to swim in liquid environments, or a low-frequency-rotating magnetic field can drive it to roll in an air environment. The drug-loaded adhesion patch can attach to both PLA and mucosa, ensuring the bond to the robot during movement and maintaining mucoadhesion to the intestinal mucosa during drug release. The initial contact force applied by a magnet between the robot and the intestinal surface was calculated and measured. The adhesion functionality of the robot to porcine colon was proved in the vitro simulated adhesion experiment.
研究领域:
生物医学工程
·
药剂学
✓ 已验证
产品关联
DOI
高影响因子
Nature Communications
·
2024
·Vol. 15
·期 1
·1-12
·
IF 14.7
Zhang Tieshan,Li Gen,Ren Hao,Yang Liu,Yang Xiong,Tan Rong,Tang Yifeng,Guo Dong,Zhao Haoxiang,Shang Wanfeng,Shen Yajing
Small-scale continuum robots hold promise for interventional diagnosis and treatment, yet existing models struggle to achieve small size, precise steering, and visualized functional treatment simultaneously, termed an “impossible trinity”. This study introduces an optical fiber-based continuum robot integrated imaging, high-precision motion, and multifunctional operation abilities at submillimeter-scale. With a slim profile of 0.95 mm achieved by microscale 3D printing and magnetic spray, this continuum robot delivers competitive imaging performance and extends obstacle detection distance up to ~9.4 mm, a tenfold improvement from the theoretical limits. Besides, the robot showcases remarkable motion precision (less than 30 μm) and substantially widens the imaging region by ~25 times the inherent view. Through ex vivo trials, we validate the robot’s practicality in navigating constrained channels, such as the lung end bronchus, and executing multifunctional operations including sampling, drug delivery, and laser ablation. The proposed submillimeter continuum robot marks a significant advancement in developing biomedical robots, unlocking numerous potential applications in biomedical engineering.
研究领域:
生物医学工程
·
机器人技术
·
医学影像
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2022
·
IF 10.383
Longfu Li,Chen Xin,Yanlei Hu,Rui Li,Chuanzong Li,Yachao Zhang,Nianwei Dai,Liqun Xu,Leran Zhang,Dawei Wang,Dong Wu,Changrui Liao,Yiping Wang
Millirobots that can be actuated and accurately steered by external magnetic fields, are highly desirable for bioengineering and wearable devices. However, existing designs of millirobots are limited by their specific material composition, hindering their wider application due to a lack of scalability. Here, we present a method for the generation of heterogeneous magnetic millirobots based on magnetic coatings. The coatings, composed of hard-magnetic CrO2 particles dispersed in an adhesive solution, impart magnetic actuation to diverse substrates with planar sheets or 3D structures. Millirobots constructed from the coatings can be readily reprogrammed with intricate magnetization profiles using laser localized heating, enabling reconfigurable shape changes under magnetic actuation. Using this approach, we demonstrate on-demand maneuvering capability of reconfiguring locomotion involving crawling, overturning and rolling with a single millirobot. Various functions, including the ability to catch a fast-moving ball, object transportation, and targeted assembly, have been achieved. This adhesive strategy facilitates the design of millirobots and may open avenues to the creation of complex millirobots for broad applications.
研究领域:
生物工程
·
材料科学
·
机器人学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Smart Materials and Structures
·
2021
·Vol. 30
·期 11
·115003
·
IF 3.585
Xiaosong Li,Xinxin Li,Lvzhou Li,Tianhui Sun,Yonggang Meng,Yu Tian
Reversible adhesion has great potential in a broad range of applications such as robotic grasping, transfer printing, and precision assembling. Herein, we show a trumpet-shaped controllable adhesive structure capable of grasping and releasing millimeter-sized three-dimensional objects with an instability modulation strategy. Experimental results revealed that the strong grasping capacity via compressing derives from the dual contribution of vacuum pressure and van der Waals interactions at the contact interface, whereas the easy releasing performance via shearing/twisting is facilitated by local unsymmetric cracking and subsequent peeling at the adhesive interface. Finite element analysis validated that external load such as shearing and twisting can dynamically modulate the interfacial stress from a relatively uniform distribution to a severely uneven state through buckling, which changes the crack path and thereby destructs the adhesive interface. Furthermore, the controllable adhesive structure was successfully demonstrated to transfer various three-dimensional objects with durable performances in both air and underwater environments. This work presents a generally applicable and dexterous modulation strategy to achieve tunable adhesion for millimeter-scale and even smaller objects, which promotes the understanding and application of controllable adhesion.
研究领域:
机器人技术
·
材料科学
·
表面工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING RESEARCH & DESIGN
·
2023
·
IF 3.9
Zihao Qiao,Zezhi Chen,Huijuan Gong,Yu Wang,Huiqiang Yu,Lu Chen
This study proposes a novel millimeter-scale channel absorber for the first time, which involves carbon dioxide (CO 2 ) absorption in the channel to achieve efficient CO 2 absorption while avoiding clogging. CO 2 absorption experiments were conducted on such a channel absorber with an inner diameter of 2.3 mm to study its CO 2 mass transfer and absorption characteristics. Al 2 O 3 particles were introduced as solid impurities to evaluate its anti-clogging performance. The experimental results showed that a stable Taylor flow could be formed in the channel in appropriate gas and liquid flowrate ranges. The liquid-side volume mass transfer coefficient ( K L a ) reached 0.34 s −1 using a 6% DEA solution as the absorbent, which was approximately one order of magnitude higher than that of the conventional packed towers. When Al 2 O 3 to a maximum extent of 2 wt% was added into the absorbents, no clogging was observed, and the values of K L a even increased. Due to the excellent CO 2 absorption mass transfer and anti-clogging performance, millimeter channel absorbers have promising industrial applications for CO 2 absorption. Therefore, means and application scenario for applying millimeter-scale channel absorber in the industrial CO 2 absorption have been proposed.
研究领域:
化学工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
Science Advances
·
2023
·Vol. 9
·期 36
·
IF 13.6
Ziyang Cheng,Chuxin Li,Can Gao,Chengqi Zhang,Lei Jiang,Zhichao Dong
Liquid entrainment with a solid architecture passing through the fluid-fluid interface is ubiquitous and widely used in industrial processes as a liquid transfer method. Besides liquid properties, solid structures play a core role in entrainment. Although the influence of its macroscopic curvatures and microscale roughness has attracted years of research, the effect and potential of the commonly seen millimetric structures have not been sufficiently explored and exploited. Here, we demonstrate enhanced liquid entrainment on the millimetric structured surface by the co-effect of viscosity and capillarity for sustained liquid transfer of small deviation, including high-quantity uptake and practically operational drainage with small and relatively uniform droplet dripping time of varied liquid viscosities. With the overall process of viscous-capillary entrainment, we achieve stable cyclical arrayed liquid transport, showing its potential for sustained liquid transfer in intractable situations in laboratory, industry, and even daily life.
研究领域:
流体力学
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材料科学
·
仿生工程
·
微流控技术
·
表面工程
✓ 已验证
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2019
·
IF 3.375
Chencan Du,Peicheng Wang,Yunpeng Hu,Jisong Zhang,Guangsheng Luo
The mass transfer of cyclohexanone oxime (CHO) from n-octane (continuous phase) to H2SO4 (dispersed phase) was enhanced in milliscale packed beds under large phase ratios. The holdups of two phases were determined, and the effects of structure and operating parameters on the overall mass transfer coefficient of the organic phase (K0a) were also investigated, including placement mode, surface property, size of particle and bed, flow rate and phase ratio, and CHO concentration. Different flow regimes were found in different placement modes and surface properties. Compared with tubes, packed beds showed 1 order of magnitude increase of K0a. A prediction model for K0a was proposed and showed good agreement with the experimental results. Pressure drop and energy dissipation were further measured to access the mixing efficiency. These results are therefore expected to contribute to the novel process of the caprolactam industry and expand the applications of microflow technology.
研究领域:
化学工程
·
传质
·
过程工程
·
微流控
✓ 已验证
产品关联
DOI
高影响因子
Materials Horizons
·
2022
·Vol. 9
·期 9
·2416-2424
·
IF 15.717
Xing Xin,Yanmei Zhang,Jiamei Chen,Mao-Lin Chen,Wei Xin,Mengfan Ding,Youzhe Bao,Weizhen Liu,Haiyang Xu,Yichun Liu
Defects, such as uncontrollable vacancies, will intensively degrade the material properties and device performance of CVD-grown transition metal dichalcogenides (TMDs). Although vacancies can be repaired by some post-processing measures, these treatments are usually time-consuming, complicated and may introduce uncontrollable chemical contaminants into TMDs. How to efficiently suppress the uncontrollable defects during CVD growth and acquire intrinsic high-quality CVD-grown TMDs without any after-treatment remains a critical challenge, and has not yet been well resolved. Here, an alternate-growth-etching (AGE) CVD method was demonstrated to fabricate defect-suppressed submillimeter-scale monolayer WS2 single crystals. Compared with normal CVD, the grain size of the as-grown WS2 can be enlarged by 4–5 times (∼520 μm) and the growth rate of ∼14.4 μm min−1 is also at a high level compared to reported results. Moreover, AGE-CVD can efficiently suppress atomic vacancies in WS2. In every growth-etching cycle, the etching of WS2 occurs preferentially at the defective sites, which will be healed at the following growth stage. As a result, WS2 monolayers obtained by AGE-CVD possess higher crystal quality, carrier mobility (8.3 cm2 V−1 s−1) and PL quantum yield (QY, 52.6%) than those by normal CVD. In particular, such a PL QY is the highest value ever reported for in situ CVD-grown TMDs without any after-treatment, and is even comparable to the values of mechanically exfoliated samples. This AGE-CVD method is also appropriate for the synthesis of other high-quality TMD single crystals on a large-scale.
研究领域:
材料科学
·
纳米技术
·
凝聚态物理
·
半导体材料
·
光电子学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）