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Dynamics of metal anode morphology: insights into aqueous Zn and Sn metal batteries at different current densities
No full textAqueous batteries, renowned for their cost-effectiveness and non-flammability, have attracted considerable attention in the realm of batteries featuring Zn-based and Sn-based configurations. These configurations employ Zn and Sn metal anodes, respectively. While the growth patterns of Zn under various current densities have been extensively studied, there has been a scarcity of research on Sn dendrite growth. Our operando imaging analysis reveals that, unlike Zn, Sn forms sharp dendrites at high current density emphasizing the crucial necessity for implementing strategies to suppress the dendrites formation. To address this issue, we introduced a carbon nanotube (CNT) layer on copper foil, effectively preventing the formation of Sn dendrites under high current density, thus enabling the high-current operation of Sn metal batteries. We believe that our work highlights the importance of suppressing dendrite formation in aqueous Sn metal batteries operating at high current density and introduces a fresh perspective on mitigating Sn dendrite formation. (c) 2025 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. and Science Press. All rights are reserved, including those for text and data mining, AI training, and similar technologies.N
Novel Gas Sensor Signal Acquisition Method: Amplifying Sensor Signals and Enabling Efficient Gas Identification
No full textEnhancing sensor sensitivity and gas identification capabilities is essential for the broad application of gas sensors. Developing efficient transducing methods for sensors can be applied to a wide range of sensors. However, developing such methods for resistive sensors remains challenging. In this study, an operating method that enhances both sensitivity and gas identification capability in resistive gas sensors is presented. The sensor operation is divided into two phases: the reaction phase and the signal detection phase, and propose optimized operating methods for each. In the reaction phase, the chemisorption of oxidizing and reducing gases are maximized through appropriate operating methods for each. In the signal detection phase, a read-bias technique is introduced, enhancing sensitivity across all gases, with a 23-fold increase for 500 ppb NO2 and a sixfold increase for 50 ppm H2S. Additionally, the limit of detection (LOD) can be improved, with the NO2 LOD reduced from 11.8 to 1.4 ppb. Furthermore, a method for obtaining gas-specific signal patterns is presented that reflect the unique diffusion properties of each gas by simply adjusting the signal readout conditions. This approach demonstrates the accurate identification of four different gases using only a single sensor.Y
Korean Guidelines for Diagnosis and Management of Idiopathic Nonspecific Interstitial Pneumonia
No full textIdiopathic nonspecific interstitial pneumonia (iNSIP) is recognized as a distinct entity among various types of idiopathic interstitial pneumonias. It is identified histologically by the nonspecific interstitial pneumonia pattern. A diagnosis of iNSIP is feasible once secondary causes or underlying diseases are ruled out. Usually presenting with respiratory symptoms such as shortness of breath and cough, iNSIP has a subacute or chronic course. It predominantly affects females aged 50 to 60 years who are non-smokers. Key imaging findings on chest high-resolution computed tomography include bilateral reticular opacities in lower lungs, traction bronchiectasis, reduced lung volumes and, ground-glass opacities. Abnormalities are typically diffuse across both lungs with sub-pleural distributions. Treatment often involves systemic steroids, either alone or in combination with other immunosuppressants, although evidence supporting effectiveness of these treatments is limited. Prognosis is generally more favorable for iNSIP than for idiopathic pulmonary fibrosis, with many studies reporting a 5-year survival rate above 70%. Antifibrotic agents should be considered in a condition, termed progressive pulmonary fibrosis, where pulmonary fibrosis progressively worsens.Y
Unveiling hidden diversity: new records of Chaitophorus (Hemiptera, Aphididae) in Korea from historical specimens
No full textBackground The aphid genus Chaitophorus Koch, 1854 (Hemiptera, Aphididae, Chaitophorinae) has been studied in Korea from historical specimens. New information Korean Chaitophorus aphids have been confirmed, including four new records: C. horii Takahashi, 1939; C. leucomelas Koch, 1854; C. salijaponicus Essig and Kuwana, 1918; and C. tremulae Koch, 1854. These four newly-recorded species are described with biometric measurements and illustrations. A modified taxonomic key for Korean Chaitophorus spp. is presented.N
Vertical Memristive Crossbar Array for Multilayer Graph Embedding and Analysis
No full textGraph data structures effectively represent objects and their relationships, enabling the modeling of complex connections in various fields. Recent work demonstrate that metal at diagonal crossbar arrays (m-CBA) can effectively represent planar graphs. However, they are unsuitable for representing multilayer graphs having multiple relationships across different layers. Using conventional software, embedding multilayer graphs in high-dimensional Euclidean spaces introduces significant mathematical complexity and computational burden, often resulting in information loss. This study proposes a unique graph embedding (mapping) method utilizing a fabricated vertical m-CBA (vm-CBA), where a custom-built measurement system thoroughly validated its functionality. This structure directly maps multilayer graphs into a 3D vm-CBA, accurately representing inter-layer and intra-layer connections. The practical link prediction and information scores across various real-world datasets demonstrated that vm-CBA achieved enhanced accuracy compared to conventional embeddings, even with a significantly decreased number of operations.Y
Efficient H2O2 Electrosynthesis in Acidic media via Multiscale Catalyst Optimization
No full textElectrochemically generating hydrogen peroxide (H2O2) from oxygen offers a more sustainable and cost-effective alternative to conventional anthraquinone process. In alkaline conditions, H2O2 is unstable as HO2-, and in neutral electrolytes, alkali cation crossover causes system instability. Producing H2O2 in acidic electrolytes ensures enhanced stability and efficiency. However, in acidic conditions, the oxygen reduction reaction mechanism is dominated by the inner-sphere electron transfer pathway, requiring careful consideration of both reaction and mass transfer kinetics. These stringent requirements limit H2O2 production efficiency, typically below 10-20% at industrial-relevant current densities (>300 mA cm(-2)). Using a multiscale approach that combines active site tuning with macrostructure tuning, this work presents an octahedron-like cobalt structure on interconnected hierarchical porous nanofibers, achieving a faradaic efficiency exceeding 80% at 400 mA cm(-2) and stable operation for over 120 h at 100 mA cm(-2). At 300 mA cm(-2), the optimized catalyst demonstrates a cell potential of 2.14 V, resulting in an energy efficiency of 26%.N
Strategies for mitigating data heterogeneities in AI-based neuro-disease detection
No full textIn this NeuroView, we discuss challenges and best practices when dealing with disease-detection AI models that are trained on heterogeneous clinical data, focusing on the interrelated problems of model bias, causality, and rare diseases.N
Molecularly Engineered Artificial Solid Electrolyte Interphase with Tailored Lithiophilicity and Solvent-Phobicity for Stable Lithium Metal Batteries
No full textLithium (Li) metal is recognized as a promising anode material for rechargeable batteries primarily due to its high specific capacity and energy density. However, a major challenge persists in uncontrolled Li electrodeposition and irregular solid electrolyte interphase (SEI) formation during cycling, leading to premature cell failure and safety hazards. Herein, an artificial SEI is presented for Li metal with tailored lithiophilicity and solvent-phobicity to address these critical issues. As a model system for the artificial SEI, a series of polyethyleneimine (PEI) substituted by 1,2-epoxyhexane (EH) (PEI-EH) is introduced, consisting of lithiophilic, nitrogen-rich PEI, which promotes Li ion solvation and regulates uniform ion flux. The abundant amine groups in PEI are partially substituted with solvent-phobic hexyl groups to reduce electrolyte swelling and prevent solvent decomposition. By systematically modulating the physical properties of PEI-EH, including polarity and mechanical characteristics, an optimized artificial protective layer for Li metal that effectively suppresses Li dendrite growth and irregular SEI formation is identified. This study highlights the importance of molecular engineering in the design of artificial SEIs for achieving dendrite-free, long-lasting Li metal batteries.N
A Low-Reference-Spur and Low-Jitter D-Band PLL With Complementary Power-Gating Injection-Locked Frequency-Multiplier-Based Phase Detector
No full textThis letter presents a D-Band fundamental-sampling phase-locked loop (FS-PLL) featuring a complementary power-gating injection locking frequency-multiplier-based phase detector (CPG-ILFM PD). To reduce the level of the reference spur, the proposed CPG-ILFM PD employs two replica voltage-controlled oscillators (RVCOs) that are alternatively switched to detect the phase error of the main VCO. This approach mitigates the binary frequency shift keying (BFSK)-like modulation typically observed in conventional ILFM PDs. Additionally, the loop bandwidth of the PLL was extended, effectively suppressing the poor out-of-band phase noise (PN) of the D-Band main VCO and enhancing jitter performance. Fabricated in a 40-nm CMOS process, the proposed D-Band PLL achieved a reference spur of – 51 dBc and an RMS jitter of 65.6 fs while consuming 59.5 mW of power. This results in a jitter FoM of –245.9 dB at 119.5 GHz.N
A 41.32Gb/s 1.8 pJ/bit Collaborative Baud-Rate CDR With Background Eye-Climbing Algorithm and Low-Power Global Clock Distribution
No full textThis article presents design techniques for an energy-efficient multi-lane receiver (RX) with baud-rate clock and data recovery (CDR), which is essential for high-throughput low-latency communication in high-performance computing systems. The proposed low-power global clock distribution not only significantly reduces power consumption across multi-lane RXs but is capable of compensating for the frequency offset without any phase interpolators (PIs). To this end, a fractional divider (FDIV) controlled by CDR is placed close to the global phase locked loop. Moreover, in order to address the suboptimal lock point of conventional baud-rate phase detectors, the proposed CDR employs a background eye-climbing algorithm (ECA), which optimizes the sampling phase and maximizes the vertical eye margin (VEM). Fabricated in a 28 nm CMOS process, the proposed 43.32Gb/s RX shows a low integrated fractional spur of -40.4 dBc at a 2500 ppm frequency offset. Furthermore, it improves bit-error-rate (BER) performance by increasing the VEM by 26 mV. The entire RX achieves the energy efficiency of 1.8 pJ/bit with the aggregate data rate of 128 Gb/s.N