Structurally engineered heat loss suppression in nanogap-aligned nanowires for power efficient heating.

Thermal management at the nanoscale offers potential advancements in power-efficient geometrical design; however, both conduction- and convection-based structural optimization have yet to be fully investigated due to dimensional limitations. In this study, we analytically designed a structured configuration within a regime comparable to the mean free path of heat-transferring carriers. The optimally designed nanowire configuration, featuring aligned nanowires with narrow gaps (∼22 nm), was designed based on the analytic calculation.

"Straw in the Clay Soil" Strategy: Anticarbon Corrosive Fluorine-Decorated Graphene Nanoribbons@CNT Composite for Long-Term PEMFC.

Carbon corrosion poses a significant challenge in polymer electrolyte membrane fuel cells (PEMFCs), leading to reduced cell performance due to catalyst layer degradation and catalyst detachment from electrodes. A promising approach to address this issue involves incorporating an anticorrosive carbon material into the oxygen reduction reaction (ORR) electrode, even in small quantities (≈3 wt% in electrode). Herein, the successful synthesis of fluorine-doped graphene nanoribbons (F-GNR) incorporated with graphitic carbon nanotubes (F-GNR@CNT), demonstrating robust resistance to carbon corrosion is reported.

Accelerated Conversion of Polysulfides for Ultra Long-Cycle of Li-S Battery at High-Rate over Cooperative Cathode Electrocatalyst of NiCoS/N-Doped CNTs.

Despite the very high theoretical energy density, Li-S batteries still need to fundamentally overcome the sluggish redox kinetics of lithium polysulfides (LiPSs) and low sulfur utilization that limit the practical applications. Here, highly active and stable cathode, nitrogen-doped porous carbon nanotubes (NPCTs) decorated with NiCoS nanocrystals are systematically synthesized as multi-functional electrocatalytic materials. The nitrogen-doped carbon matrix can contribute to the adsorption of LiPSs on heteroatom active sites with buffering space.

A wireless, implantable bioelectronic system for monitoring urinary bladder function following surgical recovery.

Partial cystectomy procedures for urinary bladder-related dysfunction involve long recovery periods, during which urodynamic studies (UDS) intermittently assess lower urinary tract function. However, UDS are not patient-friendly, they exhibit user-to-user variability, and they amount to snapshots in time, limiting the ability to collect continuous, longitudinal data. These procedures also pose the risk of catheter-associated urinary tract infections, which can progress to ascending pyelonephritis due to prolonged lower tract manipulation in high-risk patients.

Toxic dinoflagellate Centrodinium punctatum (Cleve) F.J.R. Taylor: An examination on the responses in growth and toxin contents to drastic changes of temperature and salinity.

To understand environmental effects affecting paralytic shellfish toxin production of Centrodinium punctatum, this study examined the growth responses, and toxin contents and profiles of a C. punctatum culture exposed to drastic changes of temperature (5-30 °C) and salinity (15-40). C.

Development of Shape Prediction Model of Microlens Fabricated via Diffuser-Assisted Photolithography.

The fabrication of microlens arrays (MLAs) using diffuser-assisted photolithography (DPL) has garnered substantial recent interest owing to the exceptional capabilities of DPL in adjusting the size and shape, achieving high fill factors, enhancing productivity, and ensuring excellent reproducibility. The inherent unpredictability of light interactions within the diffuser poses challenges in accurately forecasting the final shape and dimensions of microlenses in the DPL process. Herein, we introduce a comprehensive theoretical model to forecast microlens shapes in response to varying exposure doses within a DPL framework.

Longevous Cycling of Rechargeable Zn-Air Battery Enabled by "Raisin-Bread" Cobalt Oxynitride/Porous Carbon Hybrid Electrocatalysts.

Developing commercially viable electrocatalyst lies at the research hotspot of rechargeable Zn-air batteries, but it is still challenging to meet the requirements of energy efficiency and durability in realistic applications. Strategic material design is critical to addressing its drawbacks in terms of sluggish kinetics of oxygen reactions and limited battery lifespan. Herein, a "raisin-bread" architecture is designed for a hybrid catalyst constituting cobalt nitride as the core nanoparticle with thin oxidized coverings, which is further deposited within porous carbon aerogel.

Bloom development of toxic dinoflagellate Alexandrium catenella (Group I) in Jinhae-Masan Bay, Korea: Germination strategy of resting cysts in relation to temperature and salinity.

To better understand the role of resting cysts in the outbreak of paralytic shellfish poisoning and bloom dynamics in Jinhae-Masan Bay, Korea, this study investigated the germination features of ellipsoidal Alexandrium cysts isolated from sediments collected in winter and summer under different combinations of temperature and salinity. Morphology and phylogeny of germling cells revealed that the ellipsoidal Alexandrium cysts belong to Alexandrium catenella (Group I). The cysts could germinate across a wide range of temperature (5-25 °C) with germination success within 5 days, indicating that continuous seeding for the maintenance of vegetative cells in the water column may occur through the year without an endogenous clock to regulate germination timing.

Experimental and Computational Approaches to Sulfonated Poly(arylene ether sulfone) Synthesis Using Different Halogen Atoms at the Reactive Site.

Engineering thermoplastics, such as poly(arylene ether sulfone), are more often synthesized using F-containing monomers rather than Cl-containing monomers because the F atom is considered more electronegative than Cl, leading to a better condensation polymerization reaction. In this study, the reaction's spontaneity improved when Cl atoms were used compared to the case using F atoms. Specifically, sulfonated poly(arylene ether sulfone) was synthesized by reacting 4,4'-dihydroxybiphenyl with two types of biphenyl sulfone monomers containing Cl and F atoms.

Micro-/Nano-Structured Biodegradable Pressure Sensors for Biomedical Applications.

The interest in biodegradable pressure sensors in the biomedical field is growing because of their temporary existence in wearable and implantable applications without any biocompatibility issues. In contrast to the limited sensing performance and biocompatibility of initially developed biodegradable pressure sensors, device performances and functionalities have drastically improved owing to the recent developments in micro-/nano-technologies including device structures and materials. Thus, there is greater possibility of their use in diagnosis and healthcare applications.

High-speed, scanned laser structuring of multi-layered eco/bioresorbable materials for advanced electronic systems.

Physically transient forms of electronics enable unique classes of technologies, ranging from biomedical implants that disappear through processes of bioresorption after serving a clinical need to internet-of-things devices that harmlessly dissolve into the environment following a relevant period of use. Here, we develop a sustainable manufacturing pathway, based on ultrafast pulsed laser ablation, that can support high-volume, cost-effective manipulation of a diverse collection of organic and inorganic materials, each designed to degrade by hydrolysis or enzymatic activity, into patterned, multi-layered architectures with high resolution and accurate overlay registration. The technology can operate in patterning, thinning and/or cutting modes with (ultra)thin eco/bioresorbable materials of different types of semiconductors, dielectrics, and conductors on flexible substrates.

Electro-Design of Bimetallic PdTe Electrocatalyst for Ethanol Oxidation: Combined Experimental Approach and Ab Initio Density Functional Theory (DFT)-Based Study.

An alternative electrosynthesis of PdTe, using the electrochemical atomic layer deposition (E-ALD) method, is reported. The cyclic voltammetry technique was used to analyze Au substrate in copper (Cu), and a tellurous (Te) solution was used to identify UPDs and set the E-ALD cycle program. Results obtained using atomic force microscopy (AFM) and scanning electron microscopy (SEM) techniques reveal the nanometer-sized flat morphology of the systems, indicating the epitaxial characteristics of Pd and PdTe nanofilms.

Soft, bioresorbable coolers for reversible conduction block of peripheral nerves.

Implantable devices capable of targeted and reversible blocking of peripheral nerve activity may provide alternatives to opioids for treating pain. Local cooling represents an attractive means for on-demand elimination of pain signals, but traditional technologies are limited by rigid, bulky form factors; imprecise cooling; and requirements for extraction surgeries. Here, we introduce soft, bioresorbable, microfluidic devices that enable delivery of focused, minimally invasive cooling power at arbitrary depths in living tissues with real-time temperature feedback control.

How to Change the Reaction Chemistry on Nonprecious Metal Oxide Nanostructure Materials for Electrocatalytic Oxidation of Biomass-Derived Glycerol to Renewable Chemicals.

Au and Pt are well-known catalysts for electrocatalytic oxidation of biomass-derived glycerol. Although some nonprecious-metal-based materials to replace the costly Au and Pt are used for this reaction, the fundamental question of how the nonprecious catalysts affect the reaction chemistry and mechanism compared to Au and Pt catalysts is still unanswered. In this work, both experimental and computational methods are used to understand how and why the reaction performance and chemistry for the electrocatalytic glycerol oxidation reaction (EGOR) change with electrochemically-synthesized CuCo-oxide, Cu-oxide, and Co-oxide catalysts compared to conventional Au and Pt catalysts.

Wireless and Linear Hydrogen Detection up to 4% with High Sensitivity through Phase-Transition-Inhibited Pd Nanowires.

Palladium (Pd) has been drawing increasing attention as a hydrogen (H) detecting material due to its highly selective sensitivity to H. However, at H concentrations above 2%, Pd undergoes an inevitable phase transition, causing undesirable electrical and mechanical alterations. In particular, nonlinear gas response (Δ/) that accompanies phase transition has been a great bottleneck for detecting H in high concentrations, which is especially important as there is a risk of explosion over 4% H.

Aligned CuO nanowire array for a high performance visible light photodetector.

Recently, copper oxide (CuO) has drawn much attention as a promising material in visible light photodetection with its advantages in ease of nanofabrication. CuO allows a variety of nanostructures to be explored to enhance the optoelectrical performance such as photogenerated carriers scattering and bandgap engineering. However, previous researches neglect in-depth analysis of CuO's light interaction effects, restrictively using random orientation such as randomly arranged nanowires, single nanowires, and dispersed nanoparticles.

Efficient Zn Metal Anode Enabled by O,N-Codoped Carbon Microflowers.

Zinc metal anodes show great promise for cheap and safe energy storage devices. However, it remains challenging to regulate highly efficient Zn plating/stripping under a high depth of discharge (DOD). Guided by density functional theory calculation, we here synthesized an oxygen- and nitrogen-codoped carbon superstructure as an efficient host for high-DOD Zn metal anodes through rational monomer selection, polymer self-assembly, and structure-preserved carbonization.

Alexandrium catenella (Group I) and A. pacificum (Group IV) cyst germination, distribution, and toxicity in Jinhae-Masan Bay, Korea.

To better understand the outbreaks of paralytic shellfish poisoning and bloom dynamics caused by Alexandrium species in Jinhae-Masan Bay, Korea, the germination and distributions of ellipsoidal Alexandrium cysts were investigated, and paralytic shellfish toxins (PSTs) profiles and contents were determined using strains established from germling cells. The phylogeny and morphological observations revealed that the germinated vegetative cells from ellipsoidal cysts collected from the surface sediments in Jinhae-Masan Bay belong to Alexandrium catenella (Group I) and A. pacificum (Group IV) nested within A.

Photocurable bioresorbable adhesives as functional interfaces between flexible bioelectronic devices and soft biological tissues.

Flexible electronic/optoelectronic systems that can intimately integrate onto the surfaces of vital organ systems have the potential to offer revolutionary diagnostic and therapeutic capabilities relevant to a wide spectrum of diseases and disorders. The critical interfaces between such technologies and living tissues must provide soft mechanical coupling and efficient optical/electrical/chemical exchange. Here, we introduce a functional adhesive bioelectronic-tissue interface material, in the forms of mechanically compliant, electrically conductive, and optically transparent encapsulating coatings, interfacial layers or supporting matrices.