LANGMUIR
·
2023
·
IF 3.9
Yitan Li,Yuguang Chen,Yan Li,Howard A. Stone,Amir A. Pahlavan,Steve Granick
The shapes of highly volatile oil-on-water droplets become strongly asymmetric when they are out of equilibrium. The unsaturated organic vapor atmosphere causes evaporation and leads to a strong Marangoni flow in the bath, unlike that previously seen in the literature. Inspecting these shapes experimentally on millisecond and submillimeter time and length scales and theoretically by scaling arguments, we confirm that Marangoni-driven convection in the subphase mechanically stresses the droplet edges to an extent that increases for organic droplets of smaller contact angle and accordingly smaller thickness. The viscous stress generated by the subphase overcomes the thermodynamic Laplace pressure. The oil droplets develop copious regularly spaced fingers, and these fingers develop spike-shaped and branched treelike structures. Unlike this behavior for single-component (surfactant-free) oil droplets, droplets composed of two miscible (surfactant-free) organic liquids develop a rim of the less volatile component along the droplet perimeter, from which jets of monodisperse smaller droplets eject periodically due to the Rayleigh–Plateau instability. When evaporation shrinks droplets to μm size, their shapes fluctuate chaotically, and ellipsoidal shapes rupture into smaller daughter droplets when subphase convection flow pulls them in opposite directions. The shape of the evaporating oil droplets is kneaded and sculpted by vigorous flow in the water subphase.
研究领域:
物理学
·
流体力学
✓ 已验证
DOI
高影响因子
Nature Communications
·
2025
·Vol. 16
·期 1
·1-10
·
IF 15.7
Wang Xin,Xia Neng,Pan Chengfeng,Zhao Jinsheng,Hao Bo,Su Lin,Jin Dongdong,Xu Qingsong,Liu Xurui,Hou Xingyu,Zhang Li
Water surface jumping motions of semi-aquatic insects are primarily rely on surface tension-dominated jumping mechanism to achieve impressive jumping performance. However, this mechanism faces an inherent physical constraint: the propulsion force must remain below the threshold required to break the water surface, limiting efficient momentum acquisition. Herein, we present a water surface jumping strategy that addresses the limitations of surface tension-dominated mechanism. Our approach allows the engineered jumper to achieve a record-breaking jumping height of 18 body lengths (63 cm) and take-off velocity of 100.6 body length/s (3.52 m/s). This strategy is built on three key design principles: (I) superhydrophobic body for floating on water surface, (II) light-weight, high-power actuation module capable of providing significant propulsion force within an ultrashort time, (III) well-engineered momentum transmission system for efficient kinetic energy transfer. The developed soft jumper based on these design principles advances the development of water environment related robotics.
研究领域:
仿生学
·
机器人学
·
流体力学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2022
·
IF 9.136
Weijie Hua,Yong Kang,Shuai Liu
A novel method of water surface plasma (WSP) combined with peroxymonosulfate (PMS) was developed for synergistic degradation of aqueous ciprofloxacin hydrochloride (CIP). The synergistic effect between WSP and PMS was demonstrated with the synergistic factor of 3.224. The CIP removal efficiency of the synergistic system was up to 96.6 % after 30 min of treatment, corresponding to the kinetic constant of 0.113 min −1 . The degradation performance experiments revealed that the PMS dosage of 6.4 mM, air flow rate of 0 L/min, peak voltage of 23 kV, initial pH and initial CIP concentration of acidic and 20 mg/L, respectively, were favorable for CIP removal. The combined system could maintain high removal efficiency (93.9 %) for the treatment of wastewater with high initial conductivity (950 μS/cm). OH, SO 4 − , O 3 , O 2 − and high-energy electrons were the active species responsible for CIP degradation, among which OH was the main active factor. UV–vis spectra and three-dimensional fluorescence spectra demonstrated the efficient removal of CIP. Possible degradation pathways and synergistic degradation mechanism were summarized. PMS was probably activated by O 3 , ultraviolet light and high-energy electrons generated in WSP. The presence of Cl − , SO 4 2− and HCO 3 − had a certain negative effect on CIP degradation in the WSP + PMS system, while HA had little effect on the final removal of CIP. The WSP + PMS degradation method has the advantages of high efficiency, high rate and low energy consumption compared with the previous literatures.
研究领域:
环境科学
·
水处理
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2021
·
IF 10.588
Zhuo Chen,Qianying Wu,Ying Xu,Jinhan Mo
Organic films were widely found on indoor impermeable surfaces exposed to gaseous organic compounds, but few studies have addressed the film growth details on different indoor substrates. In this study, we observed the topography evolution of phthalic acid ester (PAE) organic films on three impermeable substrates: polished glass (G-P), mirror-polished stainless steel (SS-M) and drawn stainless steel (SS-D). PAE organic films were preferentially formed upon the flat surface with sparse inherent nano-peaks of substrate G-P and in valleys of substrate SS-M and SS-D. Surface uniformity of substrates and viscosity of PAE molecules were inferred as critical parameters determining the surface average adhesion forces. We obtained the partition coefficients of DEP , DnBP, BBP and DEHP on substrate G-P, SS-M and SS-D by fitting the initial monolayer adsorption process. Organic films continuously grew instead of reaching adsorption equilibrium after long-term PAE exposure, indicating that multilayer adsorption may occur. The organic film growth rates in saturated gas-phase PAE concentrations were quantified as about one-tenth of the results in previous studies where substrates were simultaneously exposed to multiple pollutants. To sum up, the results outline PAE adsorption details on impermeable materials and provide a reference for better estimation on PAE exposure assessment.
研究领域:
环境科学
·
化学
·
材料科学
✓ 已验证
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2023
·Vol. 33
·期 23
·2213788
·
IF 19
Yanling Xiao,Wei Deng,Jiajing Hong,Xiaobin Ren,Xiujuan Zhang,Jialin Shi,Fangming Sheng,Xiaohong Zhang,Jiansheng Jie
Application-oriented growth of patterned organic semiconductor (OSC) thin films with a single domain is a nonnegotiable requirement for the manufacturing of high-performance organic electronic devices. However, the prevalent selective-wetting patterning method remains a challenge in controlling the density of nucleation events in microscale spaces, resulting in thin films with high grain boundary density and no preferential orientation spherulites. Herein, a simple double-blade-coating printing technique using a combination of wetting-patterned substrates to produce an array of highly crystalline OSC thin films is developed. Specifically, the approach confines the OSC crystallization on a molecular-flat water surface in specific areas, enabling a significant reduction in the number of nuclei. Consequently, patterned 2,7-dioctyl[1]benzothieno[3,2-b] benzothiophene (C 8 -BTBT) thin films comprising single-crystal domains are achieved with an exceptionally high yield of 62.5%. The organic field-effect transistor array developed from such patterns of C 8 -BTBT single-crystalline films exhibits an excellent average mobility of 11.5 cm 2 V −1 s −1 which is 12.5-fold higher compared to that of the reference sample fabricated via conventional single-blade coating. It is believed that this approach can be widely applied to other soluble organic materials, thereby opening up opportunities for fabricating multicomponent integrated electronics.
研究领域:
材料科学
·
纳米技术
·
有机电子学
·
半导体器件
✓ 已验证
DOI
高影响因子
KOREAN JOURNAL OF CHEMICAL ENGINEERING
·
2023
·Vol. 40
·期 5
·1122-1132
·
IF 2.7
Hua Weijie,Kang Yong
A coupling method of water surface plasma (WSP) with β -Bi 2 O 3 /CaFe 2 O 4 composite was applied to promote the elimination of aqueous Orange G (OG). The morphology, structures, crystal form and chemical bonding state of the prepared β -Bi 2 O 3 /CaFe 2 O 4 composite were characterized via SEM, TEM, EDS-mapping, XRD, FT-IR and XPS. The results showed that the addition of composites significantly enhanced the degradation and kinetic constant of OG. The degradation efficiency of the combined system containing 8.0 wt% β -Bi 2 O 3 /CaFe 2 O 4 composite was 28.9% higher compared to the sole WSP for OG degradation. The synergistic factor (2.387) demonstrated that the combined system was able to establish a synergistic effect. The effect including peak voltage, air flow rate, initial conductivity and initial concentration of solution on OG removal was inspected. The active species trapping experiments demonstrated ·OH, h + , ·O
− 2
and high-energy electrons devoted to OG removal in the combined system. O 3 and H 2 O 2 were also involved in the OG removal in the combined system. Three-dimensional fluorescence spectroscopy and liquid chromatography-mass spectrometry were tested to investigate the mechanism of OG degradation. Finally, the combined system in the present study was compared with other competitive technologies for the degradation of OG in the literature.
研究领域:
环境科学
·
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Nano Today
·
2022
·
IF 18.962
Xiao Yang,Yuanhao Chen,Xuan Zhang,Pan Xue,Pengfei Lv,Yanzhao Yang,Ling Wang,Wei Feng
Walking on water is a unique locomotion mode found in aquatic living creatures. However, it remains challenging to create light-driven aquatic soft robots that can walk freely on water surface. Herein, water strider-inspired water-walking soft robots that can be remotely controlled by light are demonstrated through combining superhydrophobic floating surface with hierarchical nanostructures and light-driven soft-actuation legs that are fabricated through in situ embedding of judiciously designed polymerizable miniaturized gold nanorods (MiniGNR nanomonomer) in liquid crystal network (LCN)-based soft actuators. The MiniGNRs-LCN soft actuators act as driving paddles to enable propulsive motion on the water surface, and the superhydrophobic surface facilitates the aquatic soft robots with weight-bearing and drag-reducing ability. Upon cyclic exposure to near-infrared light, the LCN-based actuation leg quickly exhibits a photoinduced shape-bending deformation, enabling the one-legged soft robot to walk on water surface unidirectionally through horizontal momentum transfer of photoinduced actuation force to the water. Taking advantage of tailorable photoresponsiveness of MiniGNR nanomonomer, a tri-legged water-walking soft robot that can execute visible/infrared wavelength-dependent multi-directional motions is further demonstrated for cargo transportation. This research may provide a new toolbox for the development of untethered soft robots with sophisticated spatiotemporal actuation toward aquatic complex environments.
研究领域:
机器人技术
·
材料科学
·
纳米技术
·
生物力学
✓ 已验证
产品关联
DOI
高影响因子
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