Publications by authors named "Zhiwu Han"

Wearable sweat sensors enable non-invasive tracking and monitoring of human physiological information, which is expected to attract wide interest and rapid development in dietary health management and disease prevention. Unfortunately, sweat sensors are limited by rapid evaporation and low secretion rates of sweat. Herein, a sweat detection patch is proposed, which integrates bionic microchannels and multiparameter electrochemical sensors.

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Bionic neural devices often feature complex structures with multiple interfaces, requiring extensive post-processing. In this paper, a neural device with intrinsic perception and decision-making (NDIPD), inspired by neuronal oscillatory activity is introduced. The device utilizes alternating signals generated by coupling the human body with the power-frequency electromagnetic field as both a signal source and energy source, mimicking neuronal oscillatory activity.

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Slender tubes are in high demand owing to their lightweight and outstanding energy absorption. However, conventional slender tubes are prone to catastrophic failures such as Euler's buckling under axial load. Interestingly, growing bamboos overcome this similar dilemma via a unique tapered intine in the internodes, which endows them with excellent energy absorption.

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Mechanical information is a medium for perceptual interaction and health monitoring of organisms or intelligent mechanical equipment, including force, vibration, sound, and flow. Researchers are increasingly deploying mechanical information recognition technologies (MIRT) that integrate information acquisition, pre-processing, and processing functions and are expected to enable advanced applications. However, this also poses significant challenges to information acquisition performance and information processing efficiency.

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Flexible pressure sensors have shown significant application prospects in fields such as artificial intelligence and precision manufacturing. However, most flexible pressure sensors are often prepared using polymer materials and precise micronano processing techniques, which greatly limits the widespread application of sensors. Here, this work chooses textile material as the construction material for the sensor, and its latitude and longitude structure endows the sensor with a natural structure.

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Flexible pressure sensor is a crucial component of tactile sensors and plays an integral role in numerous significant fields. Despite the considerable effort put forth, how to further improve sensitivity with ingenious yet easy-to-manufacture structures and apply them to emerging fields such as structure/materials recognition, human motion monitoring, and human-machine interaction remains a challenge. Here, we develop a highly sensitive flexible capacitive pressure sensor featuring a structured electrode layer with embedded microcracks and a dielectric layer with micro-convex structures, which are combined with an iontronic interface.

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Advanced epoxy (EP)-based composites, retaining excellent physical and mechanical properties, are in demand in many high-end devices, such as fan blades of aeroengines. However, the irreconcilable conflict between stiffness and toughness within an EP often leads to catastrophic brittle fracture. Herein, inspired by the medulla skeleton of wing feathers of , bioinspired EP-based composites (BECs) were obtained via integrating functionalized three-dimensional interconnected skeleton into a brittle EP.

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Unmanned probes, mainly powered by solar panels, are effective tools for exploiting space resources to expand the human habitat. However, it remains a great challenge for the unmanned probes to actively repel multiscale dust particles in space. Inspired by the synergistic antifouling mechanism of fly wings and legs, a biomimetic dynamic antifouling surface (BDAS) was prepared based on a combination of self-assembly and template inversion.

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Introducing biological structures into materials design is expected to develop strong and tough structural materials. However, multiple interfaces are introduced simultaneously. They are always the weakest part of load transfer, becoming a critical vulnerability and failure-prone area.

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Article Synopsis
  • Mechano-bactericidal strategies offer a sustainable way to combat microbial contamination, but their effectiveness against Gram-positive bacteria is limited due to their tough cell walls.
  • A new intelligent biomimetic nanopillared biopatch enhances antibacterial effectiveness to over 99% against resistant Gram-positive bacteria when stimulated by low-voltage electrical energy.
  • The biopatch not only provides effective infection control without risk of resistance but also functions as a temperature sensor to monitor wound conditions, showcasing its potential for improved healing and management of wounds.
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Photovoltaic devices are essentially solar energy collectors that convert incident photons into charge carriers. However, light reflection losses and external factors (e.g.

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Antireflection (AR) surfaces are essential for the fields of flexible displays, photovoltaic industry, medical endoscope, intelligent windows, etc. Although natural creatures with well-organized micro/nanostructures have provided some coupling design principles for the rapid development of bioinspired AR materials, the mechanical vulnerability, poor flexibility, and nonadjustability have been pointed out as the drawback of these nanostructures. Here, a bioinspired reversible AR film with 4% reflectivity, 90% transmittance, and 9% haze in broadband (400-900 nm) was prepared.

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Maintaining high separation performance during continuous emulsion separation remains a challenge. Herein, based on biomimetic coupling ideas, hole array interlaced wetting surfaces (HAIWSs) and mastoid array interlaced wetting surfaces (MAIWSs) were prepared by laser processing, electroless silver deposition, thiol modification, and spraying for on-demand emulsion separation. When the separation is going on, randomly moving emulsion droplets are prone to being captured by holes or mastoids due to interlaced wettability.

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Numerous plants evolve ingeniously microcantilever-based hairs to ultra-sensitively detect out-of-plane quasi-static tactile loads, providing a natural blueprint for upgrading the industrial static mode microcantilever sensors, but how do the biological sensory hairs work mechanically? Here, the action potential-producing trigger hairs of carnivorous Venus flytraps (Dionaea muscipula) are investigated in detail from biomechanical perspective. Under tiny mechanical stimulation, the deformable trigger hair, composed of distal stiff lever and proximal flexible podium, will lead to rapid trap closure and prey capture. The multiple features determining the sensitivity such as conical morphology, multi-scale functional structures, kidney-shaped sensory cells, and combined deformation under tiny mechanical stimulation are comprehensively researched.

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Macrostructural control of stress distribution and microstructural influence on crack propagation is one of the strategies for obtaining high mechanical properties in stag beetle upper jaws. The maximum bending fracture force of the stag beetle upper jaw is approximately 154, 000 times the weight of the upper jaw. Here, we explore the macro and micro-structural characteristics of two stag beetle upper jaws and reveal the resulting differences in mechanical properties and enhancement mechanisms.

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Article Synopsis
  • Highly robust soft strain gauges are being developed for monitoring vital signs and machine conditions, facing challenges in performance and durability due to weak connections between sensor layers.
  • A multilayer design inspired by scorpion biology successfully enhances both electrical performance and mechanical strength, achieving impressive sensitivity and stability.
  • The system includes a wireless strain monitoring application that can track human throat activities and machine health on various dynamic surfaces.
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Flexible sensors have attracted great attention in the field of wearable electronic devices due to their deformability, lightness, and versatility. However, property improvement remains a key challenge. Fortunately, natural organisms exhibit many unique response mechanisms to various stimuli, and the corresponding structures and compositions provide advanced design ideas for the development of flexible sensors.

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Biomimetic surfaces with special wettability have received much attention due to their promising prospects in droplet manipulation. Although some progress has been made, the manipulation of droplets by macroscopic defects of the millimeter structure and the wetting-state transition mechanism have rarely been reported. Herein, inspired by lotus leaves and desert beetles, biomimetic surfaces with macroscopic defects are prepared by laser processing and chemical modification.

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Various methods to solve water scarcity have attracted increasing attention. However, most existing water harvesting schemes have a high demand for preparation methods and costs. Here, a multi-biomimetic double interlaced wetting Janus surface (DIWJS) was prepared by laser for effective fog collection.

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Integrating sensors and other functional parts in one device can enable a new generation of integrated intelligent devices that can perform self-sensing and monitoring autonomously. Applications include buildings that detect and repair damage, robots that monitor conditions and perform real-time correction and reconstruction, aircraft capable of real-time perception of the internal and external environment, and medical devices and prosthetics with a realistic sense of touch. Although integrating sensors and other functional parts into self-sensing intelligent devices has become increasingly common, additive manufacturing has only been marginally explored.

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The various apple products industries produce a large amount of apple residue, which is easily fermented, causes environmental pollution, and its disposal cost is high, but is rich in nutrients, such as polyphenols. Polyphenols can be purified to realize high-value deep processing of apple pomace and to promote energy reuse of food waste. In this study, the highly selective purification of polyphenols was achieved by membrane filtration using prepared Metal-organic framework (MOF)-5/PES mixed matrix membranes with apple peels as raw material.

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The multi-level structure is a strategy to enhance the mechanical properties of dung beetle leg joints. Under external loads, the microstructure facilitates energy dissipation and prevents crack extension. The macrostructure aids in transferring the load to more reliable parts.

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Multisensory integration enables the simultaneous perception of multiple environmental stimuli while minimizing size and energy consumption. However, conventional multifunctional integration in flexible electronics typically requires large-scale horizontal sensing arrays (such as flexible printed circuit boards), posing decoupling complexities, tensile strain limitation, and spatial constraints. Herein, a fully flexible multimodal sensing system (FMSS) is developed by coupling biomimetic stretchable conductive films (BSCFs) and strain-insensitive communication interfaces using a vertical stacking integration strategy.

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Detecting airflow turbulence precursors promptly is crucial for ensuring flight safety and control. The initial stages of turbulence involve small reverse flows with random velocities and directions, which are not easily detected by existing airflow sensors. In this study, we designed a bionic, sensitivity-enhanced, bi-directional airflow sensor (BSBA) by incorporating bio-inspired circular tip slits and enlarging the central part of the cruciform beam structure.

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