Next‐generation Li‐ion batteries are being developed with high‐voltage cathodes to maximize their energy and power densities. However, the commercialization of high‐voltage cathodes has been delayed ...due to the degradations of active materials and electrolytes in long‐term cycling. Recent advances have made significant improvements in these issues; however, the corrosion of Al current collector and its effects on battery performances have not been studied in detail despite its importance. In this study, the compositional and morphological evolutions of the passivation layer formed on Al are examined. The ion fluxes of Al3+ and F− through the native oxide layer of Al play a critical role in the formation of the passivation film and the inhibition of further corrosion. However, the continuous diffusion of the ions during long‐term cycling at elevated temperature deteriorates the passivation ability of the film. An artificial diffusion barrier on the surface of Al effectively suppresses the ion fluxes to enhance the cyclability of LiNi0.5Mn1.5O4. This work contributes to improving the stability of the current collector at high voltages and serves as a benchmark for corrosion studies concerning advanced energy storage devices.
The formation and degradation mechanisms of a passivation layer on Al are elucidated in a LiPF6‐based electrolyte. It is clarified that the ion diffusions of Al3+ and F− and the following reactions play a critical role in the formation, degradation of the passivation film, and the corrosion of Al. An artificial diffusion barrier on the surface of Al suppresses the corrosion.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Microfluidic systems have shown unequivocal performance improvements over conventional bench-top assays across a range of performance metrics. For example, specific advances have been made in reagent ...consumption, throughput, integration of multiple assay steps, assay automation, and multiplexing capability. For heterogeneous systems, controlled immobilization of reactants is essential for reliable, sensitive detection of analytes. In most cases, protein immobilization densities are maximized, while native activity and conformation are maintained. Immobilization methods and chemistries vary significantly depending on immobilization surface, protein properties, and specific assay goals. In this review, we present trade-offs considerations for common immobilization surface materials. We overview immobilization methods and chemistries, and discuss studies exemplar of key approaches—here with a specific emphasis on immunoassays and enzymatic reactors. Recent “smart immobilization” methods including the use of light, electrochemical, thermal, and chemical stimuli to attach and detach proteins on demand with precise spatial control are highlighted. Spatially encoded protein immobilization using DNA hybridization for multiplexed assays and reversible protein immobilization surfaces for repeatable assay are introduced as immobilization methods. We also describe multifunctional surface coatings that can perform tasks that were, until recently, relegated to multiple functional coatings. We consider the microfluidics literature from 1997 to present and close with a perspective on future approaches to protein immobilization.
Abstract We introduce a new non-abelian quantum synchronisation model over the unitary group, represented as a gradient flow, where state matrices asymptotically converge to a common one up to phase ...translation. We provide a sufficient framework leading to quantum synchronisation based on Riccati-type differential inequalities. In addition, uniform time-delayed interaction is considered for modelling realistic communication, and we demonstrate that quantum synchronisation is persistent when a small time delay is allowed. Finally, numerical simulation is performed to visualise qualitative behaviours and support theoretical results.
Synaptic computation, which is vital for information processing and decision making in neural networks, has remained technically challenging to be demonstrated without using numerous transistors and ...capacitors, though significant efforts have been made to emulate the biological synaptic transmission such as short-term and long-term plasticity and memory. Here, we report synaptic computation based on Joule heating and versatile doping induced metal–insulator transition in a scalable monolayer-molybdenum disulfide (MoS2) device with a biologically comparable energy consumption (∼10 fJ). A circuit with our tunable excitatory and inhibitory synaptic devices demonstrates a key function for realizing the most precise temporal computation in the human brain, sound localization: detecting an interaural time difference by suppressing sound intensity- or frequency-dependent synaptic connectivity. This Letter opens a way to implement synaptic computing in neuromorphic applications, overcoming the limitation of scalability and power consumption in conventional CMOS-based neuromorphic devices.
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IJS, KILJ, NUK, PNG, UL, UM
Capillary condensation is the first-order vapor-to-liquid phase transition taking place in confined geometries. Such heterogeneous nucleation has been well described by thermodynamic laws such as the ...Kelvin equation, but the equation’s applicability at the nanoscale is still unresolved. Here, we show that the Kelvin equation is valid down to approximately 0.5 nm radius of curvature when the curvature dependence of surface tension is taken into account. By the shear-mode atomic force microscopy, we have measured directly and accurately the critical tip-surface distance (dc) at which the water meniscus is capillary condensed in ambient condition; e.g.,dc≈1.2nmat 10% relative humidity. In particular, we can determine the Tolman length, the unique characteristic of the curvature-dependent surface tension, as the single fitting parameter (δ=0.21±0.05nm). Our results that unify the validity of the Kelvin equation at molecular scale and the characterization of the curvature effect of surface tension may provide a better understanding of general nucleation phenomena in nature, including the role of nanometric aerosols in cloud formation.
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CMK, CTK, FMFMET, IJS, NUK, PNG, UL, UM, UPUK
This paper highlights the significance of safety and reliability in modern industries, particularly in sectors like petroleum and LNG, where safety valves play a critical role in ensuring system ...safety under extreme conditions. To enhance the reliability of these valves, this study aims to develop a deep learning-based prognostics and health management (PHM) model. Past empirical methods have limitations, driving the need for data-driven prediction models. The proposed model monitors safety valve performance, detects anomalies in real time, and prevents accidents caused by system failures. The research focuses on collecting sensor data, analyzing trends for lifespan prediction and normal operation, and integrating data for anomaly detection. This study compares related research and existing models, presents detailed results, and discusses future research directions. Ultimately, this research contributes to the safe operation and anomaly detection of pilot-operated cryogenic safety valves in industrial settings.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Drones, also known as unmanned aerial vehicles (UAVs) and sometimes referred to as ‘Mobile IoT’ or ‘Flying IoT’, are widely adopted worldwide, with their market share continuously increasing. While ...drones are generally harnessed for a wide range of positive applications, recent instances of drones being employed as lethal weapons in conflicts between countries like Russia, Ukraine, Israel, Palestine, and Hamas have demonstrated the potential consequences of their misuse. Such misuse poses a significant threat to cybersecurity and human lives, thereby highlighting the need for research to swiftly and accurately analyze drone-related crimes, identify the responsible pilot, and establish when and what illegal actions were carried out. In contrast to existing research, involving limited data collection and analysis of the drone, our study focused on collecting and rigorously analyzing data without restrictions from the remote controller used to operate the drone. This comprehensive approach allowed us to unveil essential details, including the pilot’s account information, the specific drone used, pairing timestamps, the pilot’s operational location, the drone’s flight path, and the content captured during flights. We developed methodologies and proposed artifacts to reveal these specifics, which were supported by real-world data. Significantly, this study is the pioneering digital forensic investigation of remote controller devices. We meticulously collected and analyzed all internal data, and we even employed reverse engineering to decrypt critical information files. These achievements hold substantial significance. The outcomes of this research are expected to serve as a digital forensic methodology for drone systems, thereby making valuable contributions to numerous investigations.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Research papers are a repository of information on the various elements that make up science and technology R&D activities. Generating knowledge maps based on research papers enables identification ...of specific areas of scientific and technical research as well as understanding of the flow of knowledge between those areas. Recently, as the number of electronic publishing and informatics archives along with the amount of accumulated knowledge related to science and technology has proliferated, the need to utilize the meta-knowledge obtainable from research papers has increased. Therefore, this study devised a model based on meta-knowledge (i.e., text information including citations, abstracts, area codes) for prediction of future growth potential using deep learning algorithms and investigated the applicability of the various forms of meta-knowledge to the prediction of future growth potential. It also proposes how to select the promising technology clusters based on the proposed model.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
We propose a Lohe matrix model in a random environment where each oscillator can be regarded as an element of a general matrix Lie group
G
. In order to make the stochastic system stays on
G
for all ...time, we introduce suitable noise terms so that the underlying manifold
G
is positively invariant under the stochastic system. Then, we formally derive the Fokker-Planck type equation defined on
G
×
g
in which
g
denotes the Lie algebra corresponding to
G
. After identifying the target Fokker-Planck equation, we especially consider the unitary group
G
=
U
(
d
)
and show that the equation on
U
(
d
)
admits a global unique solution and that it can be rigorously derived using a stochastic mean-field limit procedure with a convergence rate of order
O
(
1
/
N
)
. Finally, we restrict our concern to
G
=
SU
(
2
)
to provide explicit calculation and present the nonlinear stability of an incoherent state for the Fokker-Planck equation depending on the relation between parameters.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
•An electrolytic micropump based on PCB technology for portable lab-on-a-chip devices is designed, fabricated and characterized.•A theoretical model for pump power consumption as a function of ...electrode geometry is proposed and experimentally verified.•Flow rate and backpressure of the micropump are measured as a function of current using custom-built jigs and experimental setups.•Performance of our micropumps is thoroughly compared with that of the micropump made using conventional microfabrication.•Our PCB micropump with electroplated gold electrode yields exceptionally high flow rate up to 31.6 ml/min and backpressure up to 547 kPa.
We report for the first time an electrolytic micropump based on an electrode chip fabricated on a printed circuit board (PCB), and compare its performance with that of a micropump based on an electrode chip fabricated using conventional microfabrication. Gold interdigitated (IDT) electrodes are patterned on a PCB to minimize ohmic loss during electrolysis. Custom-built acrylic fixtures are used to characterize pumping performance of various electrode chips with different electrode shapes and materials. Hydrogen and oxygen gas bubbles produced by electrolysis generate liquid flow inside a microchannel. As predicted by the theory of water electrolysis, the micropump produces flow rate increasing linearly with current at a wide range (1 mA–2 A). Our micropump yields the maximum flow rate of 31.6 ml/min and maximum backpressure of 547 kPa (at 34 μl/min), significantly high compared with the previous micropumps based on various actuation mechanisms including piezoelectric actuation, electroosmosis and phase change. The PCB-based micropump with a thick electroplated-gold electrode (0.43 μm) chip shows the overall best performance in terms of flow generation, power consumption and cost, compared with the PCB-based pump using an thin electroless-gold electrode (0.04 μm) and the pump using a microfabricated chip with a sputtered gold electrode (0.2 μm). We anticipate the PCB-based electrolysis pump will be used in portable lab-on-a-chip devices where an integrated microscale pressure source with low power consumption and simple fabrication is crucial.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPUK, ZRSKP
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