Search Results (1,040)

Flexible pressure sensors serve as core sensing components for wearable health monitoring systems, electronic skins for soft robots, and flexible human–machine interaction devices. Benefiting from the interfacial electric double-layer polarization effect, iontronic sensing delivers far higher pressure response sensitivity than conventional parallel-plate capacitive sensors, endowing it with distinctive advantages in the detection of weak physiological signals. Nevertheless, current dense ionic thin-film dielectric layers suffer from limited deformation space under compression and poor low-pressure sensing capability. Mainstream high-precision micropillar arrays are fabricated via photolithography, 3D printing, and metal etching molds, which require costly equipment and complicated fabrication procedures, making large-area mass production unfeasible. Random frosted concave-convex microstructures feature disordered dimensions, leading to severe device hysteresis and narrow linear ranges, which fail to achieve ultrahigh sensitivity alongside a wide pressure detection range simultaneously. To address the aforementioned multiple bottlenecks, this paper proposes a low-cost resin template replication process to fabricate TPU-based ionic thin-film dielectric layers with ordered micropillar array microstructures. Combined with inkjet-printed silver conductive PI flexible electrodes, an iontronic flexible pressure sensor with a sandwich layered structure is constructed. Multi-dimensional investigations including microscopic morphology characterization, electromechanical sensing performance calibration, and human wearable application tests are systematically implemented to thoroughly elucidate the synergistic enhancement mechanism of the arrayed micropillars. Test results demonstrate that the effective pressure detection range of the sensor spans 0–1038 kPa, accommodating ultra-low pressures such as pulse signals as well as medium-to-high-pressure loads including joint bending. The sensitivity reaches 23.27 kPa⁻¹ within the low-pressure range of 0–200 kPa and remains stable at 3.52 kPa⁻¹ in the high-pressure range of 200–1038 kPa, with piecewise linear fitting correlation coefficients of 0.93 and 0.96 respectively. Both the response time and recovery time of the device are 40 ms, and the hysteresis error throughout the loading-unloading cycle is merely 2.62%. After 20,000 consecutive cyclic loading-unloading tests, the peak capacitance output only decays by 5.1%, verifying outstanding mechanical fatigue resistance and electrical stability. Validations in multi-scenario applications prove that the sensor can accurately capture human physiological and motion signals including radial artery pulses, laryngeal deformation induced by multi-syllable vocalization, and multi-angle bending of fingers and elbow joints, suitable for home-based health monitoring, quantitative rehabilitation training, flexible tactile interaction and other scenarios. The entire fabrication process eliminates high-precision micro-nano processing equipment such as photolithography systems, plasma etchers and 3D printers; only general chemical raw materials and conventional laboratory instruments are adopted. The reusable templates enable low manufacturing costs and large-area coating forming, offering a novel low-cost technical solution for the engineering implementation and industrialization of high-performance iontronic flexible pressure sensors. Full article

Femtosecond laser processing enables spatially controlled modification of the structure, composition, and functionality of advanced materials through highly localized energy deposition and laser–matter interaction mechanisms. This review discusses the role of ultrafast laser irradiation in the engineering of oxide-based functional systems, including functional oxides, oxide-containing layers, interfaces, and heterogeneous structures whose properties are substantially determined by an oxide component. The mechanisms governing laser-induced oxidation, phase transformation, elemental redistribution, defect generation, and hierarchical micro-/nanostructure formation are considered. Particular attention is given to the ability of femtosecond laser processing to create surfaces with tailored interactions with light, liquids, biological environments, and external stimuli, enabling responsive devices and advanced manufacturing strategies. Laser-modified oxide layers and nanostructured interfaces are analyzed as pathways for controlling surface energy, optical properties, chemical activity, and functional response. The relationship between laser-generated architectures and their applications in sensing, actuation, wetting control, and multifunctional systems is discussed. By connecting ultrafast laser surface engineering with emerging 4D manufacturing concepts, this review highlights femtosecond laser technologies as a versatile platform for designing systems with spatially programmed functionality and, where stimulus-dependent behavior is demonstrated, time-dependent performance. Such approaches provide opportunities for integrating adaptive oxide-based functional systems into advanced manufacturing. Full article

Visible light communication (VLC) has emerged as a transformative optical wireless technology for sixth-generation (6G) networks, offering license-free spectrum access, inherent electromagnetic-interference immunity, high spatial confinement, and the unique ability to combine high-speed wireless connectivity with solid-state lighting infrastructure. However, the transition from conventional VLC links to practical 6G optical wireless systems requires far more than advanced modulation and signal processing. Future VLC performance will be strongly determined by the co-design of photonic front-ends, including high-speed transmitters, spectrally engineered emitters, reconfigurable optical interfaces, intelligent receivers, and energy-autonomous detection units. This article provides a comprehensive, device-centered review of photonic hardware and artificial intelligence (AI) enablers for next-generation 6G VLC systems. Particular attention is given to micro-LEDs, laser diodes, color-conversion materials, including perovskite quantum dots, advanced photodetectors, imaging receivers, wavelength-shifting fiber receivers, solar-cell-based receivers, optical reconfigurable intelligent surfaces (RISs), metasurfaces, beam-steering components, and optical wireless power transfer. This review discusses how AI can support inverse photonic design, transmitter and receiver calibration, nonlinear impairment mitigation, channel-aware beam control, and energy-aware resource management. Unlike broader VLC surveys that mainly emphasize network architecture, this article provides a device-centered perspective on AI-enabled photonic integration for 6G VLC, supported by a comprehensive survey of recent experimental demonstrations. Key challenges related to bandwidth, optical efficiency, receiver field of view, mobility, safety, standardization, and practical deployment are summarized, followed by a research roadmap for 2025–2032. Full article

While the recently developed tissue clearing protocols pathoDISCO and activeDISCO significantly accelerate the clearing of large tissue specimens through active chemical dehydration using 2,2-dimethoxypropane, the final step of refractive index (RI) matching with viscous organic solvents as dibenzyl ether (DBE) remains restricted by slow passive diffusion. To overcome this bottleneck, we applied 40 kHz ultrasound using a standard, cost-effective laboratory bath to significantly enhance the diffusion kinetics of the clearing medium into large specimens. Our investigation on multi-centimeter-sized porcine muscle and human earlobe samples demonstrates that 40 kHz acoustic oscillations generated by a standard ultrasound cleaning device not only accelerate the clearing process but also yield superior and stable long-term optical transparency. We also tested 1 MHz high-frequency ultrasound but it offered no kinetic advantages and tended to induce tissue micro-fractures, an artifact we have not observed at 40 kHz at comparable energy levels. We therefore propose that standard 40 kHz ultrasound baths, ubiquitous in laboratories for cleaning purposes, represent an ideal and accessible tool for optimizing solvent-based tissue clearing. Full article

Nitrocellulose (NC) is a long-established energetic polymer whose autocatalytic NO_x-driven degradation and conversion-dependent decomposition kinetics remain challenges for thin-film micro-ignition systems. This review examines NC as an energetic polymeric binder and film-forming matrix in selected nanothermite-containing formulations and micro-igniter architectures. It evaluates reported effects of formulation composition, stabilizers, nanothermite additives, deposition route, film architecture, and device geometry on thermal behavior, ignition response, safety, and storage-related limitations. Nitrogen content, molecular-weight information, crystallinity, and morphology are treated as formulation-specific characterization data rather than universal predictors of nanothermite performance. The review critically assesses Kissinger, Ozawa–Flynn–Wall, Kissinger–Akahira–Sunose, Friedman, advanced Vyazovkin, and distributed activation-energy-model approaches. Single-step kinetic models are generally inadequate for multistep, autocatalytic NC decomposition, whereas isoconversional methods provide more informative apparent activation-energy profiles when applied appropriately. Kinetic parameters obtained using different methods, sample forms, and heating programs should not be directly compared or used alone to predict ignition behavior. The review discusses stabilizers and NC-containing MICs, emphasizing formulation-specific thermal, ignition, processing, safety, and aging outcomes. In nanothermites, NC is usually a minor component functioning mainly as a binder, dispersing matrix, film-forming material, and ignition-coupling component. Full article

Aerosol jet printing, AJP, has emerged as a versatile direct ink writing technology enabling high-resolution, non-contact patterning of diverse biomaterials across a broad viscosity range. This capability facilitates the fabrication of complex micro- and mesoscale architectures on planar and non-planar substrates, advancing applications in biosensing, microfluidics, tissue engineering, and drug delivery fields. Herein, we review the integration of this high-resolution, rapid prototyping method with bioinks, including proteins, DNA, collagen, gelatin, and silk fibroin, and analyze how processing parameters influence structural and functional outcomes designed for applications for the above mentioned biotechnological fields. The ability by aerosol jet printing to combine structural, electrical, and biological functionalities within single platforms supports the development of multifunctional biomedical devices with higher potential than those produced using other direct ink writing techniques. While challenges such as bioink stability and process scalability, as well as the lack of deeper analyses about the efficiency of real applications of aerosol-jet-printed biotools, still remain open, AJP demonstrates significant promise as an enabling technology for next-generation biofabrication, offering new avenues for personalized and flexible biomedical applications. Full article

Industrial sensor-based fault diagnosis often requires continuous data acquisition, local data processing, and timely model inference on edge devices. Although deep learning-based diagnostic methods have achieved promising performance, many existing approaches rely on cloud-centered processing pipelines that introduce communication overhead and potential data privacy concerns. This paper presents a CPU–NPU heterogeneous edge fault diagnosis framework for industrial sensor data. The framework runs on an RK3588 local edge device and includes SQLite- and RingBuffer-based data management, sliding window generation, micro-batch construction, and model inference. The CPU is responsible for data access and buffering, preprocessing, and micro-batch preparation, while the NPU executes fault diagnosis models using the RKNN runtime environment. By performing inference locally, the framework reduces the continuous transmission of raw sensor data and supports real-time fault diagnosis under resource-constrained edge devices. Experimental results demonstrate high consistency between ONNX-based CPU inference and RKNN-based NPU inference after model conversion. Furthermore, the effects of different data input paths and micro-batch configurations are systematically evaluated. A cross-platform comparison between server-class CPU/GPU execution and embedded NPU deployment is also conducted in terms of latency, throughput, and energy efficiency. The results show that RingBuffer-based streaming input significantly reduces data access overhead, while the effectiveness of NPU acceleration depends on both model structure and micro-batch size. The cross-platform results further demonstrate the energy efficiency advantages of the RK3588 platform, making it more suitable for practical deployment in resource-constrained edge scenarios. These findings provide practical insights for deploying fault diagnosis models on heterogeneous edge devices. Full article

Plant protection and sprinkler irrigation rely on common fluid dynamic processes, including liquid atomization, droplet transport, target interaction, and flow distribution. This review analyses these mechanisms within a multi-scale framework. The analysis starts with droplet–target interactions. It addresses droplet impact and foliar retention in plant protection, alongside droplet kinetic energy and soil-surface responses in irrigation. The discussion then extends to the spatial transport and distribution of sprays. At the device scale, this work examines nozzles and sprinklers from the perspective of fluid mechanics and structural innovation, detailing how nozzle geometry and flow conditions affect macroscopic application performance. Finally, this review addresses advances at the system scale, with a focus on energy consumption and data-driven performance prediction. By connecting fluid behavior across multiple spatial scales, this work links micro-scale droplet dynamics to whole-system performance and identifies directions for improving agricultural spraying and sprinkler irrigation systems. Full article

316L stainless-steel capillary tubes are important in medical devices, precision fluid transport and micro heat exchangers, but their slender geometry and dense passivation film make inner-surface finishing inefficient. This study proposes a stepwise chemical-assisted magnetorheological finishing (CMRF) process for 316L capillaries. The inner surface was first pretreated with hydrogen peroxide/oxalic acid to form a removable reaction layer, and then finished by magnetorheological abrasives. The effects of the two reagents on material removal and surface integrity were evaluated, and the optimal pretreatment was determined to be 2.25 wt.% oxalic acid and 1.5 wt.% H₂O₂. Compared with conventional magnetorheological finishing, CMRF increased the material removal rate by approximately 54% and reduced the final inner-surface roughness Sa to 0.116 μm. Characterization results show that hydrogen peroxide and oxalic acid generate a dynamic oxidation–complexation–dissolution–reoxidation cycle, converting the dense passive film into an oxygen-rich, porous, low-crystallinity reaction layer and reducing surface hardness by about 30%. This softened layer promotes preferential abrasive removal instead of direct cutting of the metallic substrate, thereby improving finishing efficiency and surface quality. Full article

Microgears enable mechanical power transmission, speed reduction, motion conversion, and synchronization in compact devices ranging from microelectromechanical systems to miniature robots and optically driven micromachines. Their behavior cannot, however, be inferred by geometrically scaling conventional gears alone. As size decreases, relative manufacturing errors, surface forces, friction, adhesion, environmental sensitivity, and metrological uncertainty become increasingly important, while torque capacity and stored kinetic energy decrease rapidly. This critical review integrates the design, manufacture, tribology, and system-level performance of microgears and microgear trains. It first clarifies dimensional terminology and derives the principal scaling relationships. It then compares external, internal, planetary, worm, bevel, compliant, and reconfigurable transmission architectures; evaluates silicon micromachining, electroforming, micro powder injection molding, microforming, micro-electrical discharge machining, ultrashort-pulse laser ablation, and additive microfabrication; and examines adhesion, friction, wear, lubrication, and environmental effects. Particular attention is paid to transmission efficiency, starting torque, backlash, transmission error, lifetime, and the influence of the measuring instrument on the observed response. The literature remains strongly weighted toward manufacturability and isolated components, whereas reproducible, loaded, system-level tests are comparatively scarce. On this basis, the review proposes a unified hierarchy of validation, a minimum functional test matrix, and scale-aware design indicators. The central conclusion is that successful microgear transmissions require concurrent design of geometry, process, surface condition, environment, load path, and measurement strategy. Full article

The simultaneous diagnosis of diseases and evaluation of age quality grades in tea leaves are critical for precision agriculture and the economic valuation of tea products. Although deep learning has shown promise in agricultural vision tasks, current multi-task models often suffer from performance degradation due to feature conflicts: tea leaf disease recognition relies heavily on macro-structural lesions, whereas tea leaf-age quality grading depends on micro-textural features such as trichome density and color uniformity. To address this discrepancy, we propose a novel dual branch fusion network. Our architecture fundamentally decouples the feature extraction process by utilizing a dual branch mechanism. The first branch employs global average pooling to capture first-order spatial statistics; it can retain the global structural layout necessary for macro-lesion detection. The second branch introduces a dimensionality-reduced self-bilinear pooling module to compute second-order covariance matrices; it can effectively capture the fine-grained textural patterns essential for micro-grade classification. These decoupled features are subsequently fused and optimized through a weighted multi-task loss function. Experimental results on a comprehensive tea leaf dataset demonstrate that the proposed dual fusion framework significantly outperforms baseline models. The proposed network can rescue the disease classification accuracy drop observed in standard bilinear models while maintaining exceptional grading performance. Furthermore, the proposed network maintains a compact parameter footprint and low computational complexity. This balance renders it suitable for deployment on agricultural Internet of Things edge devices where inference speed is critical. Full article

Additive manufacturing [AM; three-dimensional (3D) printing] is reshaping heterogeneous photocatalysis by enabling architected materials and devices that span from centimeter-scale monoliths to micro- and lab-on-chip reactors. Heterogeneous photocatalysts have traditionally been deployed as powders or simple coatings, which offer high activity but suffer from mass-transfer limitations, poor light utilization and difficult recovery. Three-dimensional (3D) printing now allows precise control over macroscopic geometry, internal channel networks and micro-/nano-scale surface texturing, creating structured photocatalysts and microreactors that can be tailored for specific photon and flow fields. In contrast to recent reviews that primarily survey materials development or additive-manufacturing routes, this work focuses on photocatalytic microreactors and lab-on-chip devices as multi-scale reactors in which catalyst composition, architected geometry, photon management and hydrodynamics are co-designed across length scales. We summarize three-dimensional 3D-printed photocatalytic systems based on polymer–oxide composites, ceramic scaffolds such as zinc oxide (ZnO)/titanium dioxide (TiO₂) clay monoliths, and laser-written titanium dioxide (TiO₂) nano-architectures, with particular emphasis on microfluidic and lab-on-chip implementations fabricated by fused deposition modeling (FDM), direct ink writing (DIW), stereolithography (SLA), digital light processing (DLP) and laser direct writing (LDW). Based on the literature data and representative case studies, we examine how architected lattices, sponges and microreactor chips affect key performance metrics—apparent rate constants, apparent quantum yield (AQY) and space–time yield (STY)—for the degradation of dyes, antibiotics, detergents and other emerging contaminants in realistic matrices, and we compile reported values to illustrate emerging performance trends and limitations. Representative case studies highlight 3D-printed manganese-doped zinc oxide (Mn:ZnO)-decorated sponges used as modular cartridges for greywater and detergent treatment, as well as laser-written titanium dioxide (TiO₂) nano-photocatalysts integrated into microchannels to couple structured light fields with controlled residence times. Finally, we outline materials and process challenges—including ultraviolet (UV) aging of polymer supports, the energy intensity of ceramic sintering and the lack of standardized testing protocols—and identify future research directions formulti-scalee modeling and techno-economic evaluation of three-dimensional (3D)-printed photocatalytic microreactors and devices. Full article

Ultrafast laser micro- and nanofabrication has emerged as a powerful platform for precision manufacturing due to the unique capability of femtosecond pulses to provide highly localized energy deposition and controlled laser–matter interactions. However, conventional scanning-based processing approaches remain limited by a fundamental trade-off between spatial resolution and fabrication throughput. Recent advances in ultrafast optical field engineering provide new strategies for overcoming these limitations through coordinated control of temporal, spatial, and spatiotemporal characteristics of ultrashort laser fields. This review presents recent developments in ultrafast optical field engineering for laser micro- and nanofabrication, covering programmable pulse shaping, spatiotemporal control, spatial light modulation, structured light approaches, holographic methods, and hybrid optical architectures. The operating principles of these technologies are discussed together with their influence on energy deposition, processing accuracy, scalability, and manufacturing efficiency. Particular attention is given to applications in high-throughput surface structuring, parallel microfabrication, three-dimensional processing, photonic device fabrication, and functional material modification. Different optical architectures are compared in terms of flexibility, optical efficiency, power-handling capability, and industrial applicability. The review highlights the transition from conventional single-spot processing toward adaptive, parallel, and programmable optical manufacturing systems, emphasizing integrated control of ultrafast optical fields as a key direction for future laser fabrication. Full article

Bisphenols, phthalates, and other plastic-associated compounds are endocrine-disrupting chemicals (EDCs), common environmental contaminants that can disrupt hormonal homeostasis. Human exposure to such chemicals occurs mainly through food packaging, consumer goods, medical devices, and the environment, starting right from early development stages up to adulthood. These chemicals might cause damage to male reproductive systems as a result of being anti-androgens and estrogenic chemicals. However, the proper development of the male reproductive system requires well-regulated hormonal signaling pathways; hence, exposure to such compounds during the developmental stages poses a great risk. Environmental exposure to plastics during fetal development may influence the development of the testes, reduce the function of the Leydig cells, disrupt steroidogenesis, and produce epigenetic modifications, as documented through studies. This has been shown to increase the risk of developing reproductive disorders and reduce the production of testosterone. Therefore, one of the pathophysiological links between endocrine disruptor exposure and ED might be testosterone deficiency. Apart from disrupting testosterone production, the plastic-sourced EDCs could influence various physiological processes associated with erectile performance, such as those related to vasculature, inflammation, metabolism, and endocrinology. In this review, a comprehensive overview of the scientific data on the effect of plastic-based EDCs on testosterone regulation and male reproductive health has been provided. The role of developmental programming, endocrine disruption, oxidative stress, epigenetics, and vascular dysfunction has been explored in detail. Moreover, the possible involvement of micro- and nanoplastics has also been reviewed. From the data that is currently available, there seems to be a physiologically plausible association between plastic-based contaminants, testosterone dysregulation, and adverse reproductive outcomes. Full article

Inhalable ribonucleic acid (RNA) nanomedicines are emerging as versatile therapeutics for respiratory diseases and pulmonary metastases, enabling localized delivery of messenger RNA (mRNA), small interfering RNA (siRNA), antisense oligonucleotides, microRNA (miRNA) mimics, self-amplifying RNA, and genome-editing systems. This review synthesizes the available evidence and argues that the field has moved beyond asking whether RNA can reach the lungs. The more consequential translational question is whether RNA cargo, nanocarrier, excipients, manufacturing process, inhalation device, and pulmonary target cell can be integrated into a reproducible therapeutic product. Current research demonstrates progress in disease-corrective mRNA expression, silencing of inflammatory and fibrotic pathways, mucosal vaccination, antiviral therapy, and localized cancer treatment, alongside advances in ionizable lipid nanoparticles, lipid–polymer hybrids, chitosan and polyethyleneimine (PEI) polyplexes, dendrimers, peptide carriers, biomimetic systems, and dry-powder formulations. Translational maturity, however, remains uneven. Many studies demonstrate carrier feasibility, reporter expression, or preclinical activity, whereas fewer establish device-compatible aerosolization, preservation of RNA integrity during processing, traversal of pulmonary barriers, target-cell engagement, repeat-dose tolerability, and clinically meaningful benefit. Development should therefore be target-defined, analytically gated, device-specific, and outcome-centered. Inhalable RNA nanomedicines are best understood as integrated pulmonary products whose success depends on preserving RNA function throughout manufacturing, aerosolization, post-deposition barrier navigation, intracellular delivery, and disease-relevant pharmacodynamic activity. Full article