The CH3NH3PbI3−xClx organic–inorganic hybrid perovskite material demonstrates remarkable resistive switching behavior, which can be applicable in resistive random access memory devices. The simply ...designed Au/CH3NH3PbI3−xClx/FTO structure is fabricated by a low‐temperature, solution‐processable method, which exhibits remarkable bipolar resistive switching and nonvolatile properties.
Ni‐rich layered LiNixCoyMn1−x−yO2 (LNCM) with Ni content over >90% is considered as a promising lithium ion battery (LIB) cathode, attributed by its low cost and high practical capacity. However, ...Ni‐rich LNCM inevitably suffers rapid capacity fading at a high state of charge due to the mechanochemical breakdown; in particular, the microcrack formation has been regarded as one of the main culprits for Ni‐rich layered cathode failure. To address these issues, Ni‐rich layered cathodes with a textured microstructure are developed by phosphorous and boron doping. Attributed by the textured morphology, both phosphorous‐ and boron‐doped cathodes suppress microcrack formation and show enhanced cycle stability compared to the undoped cathode. However, there exists a meaningful capacity retention difference between the doped cathodes. By adapting the various analysis techniques, it is shown that the boron‐doped Ni‐rich layered cathode displays better cycle stability not only by its ability to suppress microcracks during cycling but also by its primary particle morphology that is reluctant to oxygen evolution. The present work reveals that not only restraint of particle cracks but also suppression of oxygen release by developing the oxygen stable facets is important for further improvements in state‐of‐the‐art Li ion battery Ni‐rich layered cathode materials.
Herein, the effect of boron doping on oxygen stability in LiNi0.92Co0.04Mn0.04O2 (LNCM) lithium ion battery cathodes is systematically investigated using various measurements. The boron‐doped LNCM produces the textured microstructure with more oxygen stabilized facets, thus not only aiding in restraining the particle cracks but also effectively suppressing the oxygen evolution to improve the cycle stability.
Emerging classes of flexible electronic systems that can be attached to a wide range of surfaces from wearable clothes to internal organs have driven significant advances in communication protocols ...(e.g., Internet of Things, augmented reality) and clinical research, shifting today's personal computing paradigm. The field of “system on plastic” is on the verge of an innovative breakthrough toward a hypercognitive society by being fused with current neuromorphic applications in the spotlight, which can offer intelligent services such as personalized feedback therapy and autonomous driving. The novel concept of electronics for flexible and neuromorphic computing requires an important research leap in micro‐/nanoelectronics on plastics, system‐level integration techniques (interconnection and packaging), and synaptic devices. Here, representative advances and developments in the area of flexible and neuromorphic technologies are reviewed with regard to device configurations, materials, fabrication processes, and their potential research fields.
Novel electronics for flexible and neuromorphic computing can change today's personal computing paradigm toward a hypercognitive society, offering an intelligent breakthrough in diverse areas. The recent advances in the fields of flexible electronics and synaptic devices are summarized in terms of their configurations, materials, fabrication processes, and their potential research areas.
Abstract
Nonalcoholic fatty liver disease (NAFLD) is associated with obesity but also found in non-obese individuals. Gut microbiome profiles of 171 Asians with biopsy-proven NAFLD and 31 non-NAFLD ...controls are analyzed using 16S rRNA sequencing; an independent Western cohort is used for external validation. Subjects are classified into three subgroups according to histological spectra of NAFLD or fibrosis severity. Significant alterations in microbiome diversity are observed according to fibrosis severity in non-obese, but not obese, subjects.
Ruminococcaceae
and
Veillonellaceae
are the main microbiota associated with fibrosis severity in non-obese subjects. Furthermore, stool bile acids and propionate are elevated, especially in non-obese subjects with significant fibrosis. Fibrosis-related
Ruminococcaceae
and
Veillonellaceae
species undergo metagenome sequencing, and four representative species are administered in three mouse NAFLD models to evaluate their effects on liver damage. This study provides the evidence for the role of the microbiome in the liver fibrosis pathogenesis, especially in non-obese subjects.
Inorganic‐based micro light‐emitting diodes (µLEDs) have witnessed significant improvements in terms of display and biomedical applications, which can shift the paradigm of future optoelectronic ...systems. In particular, µLED displays are on the verge of becoming the next big interface platform for visual communications, expanding to various internet of things and wearable/bioapplications. Novel µLED concepts need to be upgraded to be able to satisfy their potential optoelectric applications, such as virtual reality, smart watches, and medical sensors for individual computing in this hyperconnected society. Here, representative progresses in the field of flexible µLEDs are reviewed with regard to device structures, massive µLED transfers, methods for performance enhancement, and applications.
Inorganic‐based micro light‐emitting diodes (µLEDs) can shift the paradigm of future optoelectronic systems, expanding to various internet of things and wearable/bioapplications. The comprehensive review described in this paper summarizes the recent progress in the areas of flexible µLEDs with regards to device structures, massive µLED transfers, methods for performance enhancement and applications.
Phase transition in nanomaterials is distinct from that in 3D bulk materials owing to the dominant contribution of surface energy. Among nanomaterials, 2D materials have shown unique phase transition ...behaviors due to their larger surface‐to‐volume ratio, high crystallinity, and lack of dangling bonds in atomically thin layers. Here, the anomalous dimensionality‐driven phase transition of molybdenum ditelluride (MoTe2) encapsulated by hexagonal boron nitride (hBN) is reported. After encapsulation annealing, single‐crystal 2H‐MoTe2 transformed into polycrystalline Td‐MoTe2 with tilt‐angle grain boundaries of 60°‐glide‐reflection and 120°‐twofold rotation. In contrast to conventional nanomaterials, the hBN‐encapsulated MoTe2 exhibit a deterministic dependence of the phase transition on the number of layers, in which the thinner MoTe2 has a higher 2H‐to‐Td phase transition temperature. In addition, the vertical and lateral phase transitions of the stacked MoTe2 with different crystalline orientations can be controlled by inserted graphene layers and the thickness of the heterostructure. Finally, it is shown that seamless Td contacts for 2H‐MoTe2 transistors can be fabricated by using the dimensionality‐driven phase transition. The work provides insight into the phase transition of 2D materials and van der Waals heterostructures and illustrates a novel method for the fabrication of multi‐phase 2D electronics.
Dimensionality‐driven anomalous phase transition of MoTe2 is demonstrated. The thinner MoTe2 has a higher 2H‐to‐Td phase transition temperature with distinct temperature differences. Vertical and lateral phase‐patterning is achieved by modulating the thickness via stacking and insertion of graphene. By using dimensionality‐driven phase transition, seamless Td contacts for 2H‐MoTe2 transistors are fabricated, leading to low contact resistance and high mobility.
Background
The biportal endoscope-assisted unilateral foraminal approach is an option for various foraminal pathologies. Lumbar interbody fusion is the standard treatment for foraminal stenosis ...because both direct and indirect neural decompressions can be obtained.
Method
We used the biportal endoscopic technique for extraforaminal lumbar interbody fusion (BE-EFLIF) and have described the steps, with discussion regarding the indications, advantages, possible complications, and ways to overcome complications.
Conclusion
BE-EFLIF achieves direct neural decompression of lateral spinal canal under endoscopic visualization. It achieves indirect neural decompression using a large footprint lordotic interbody cage, while preserving the lumbar posterior arch as much as possible.
In this study, the lattice Boltzmann method (LBM) is used to investigate liquid water transport in the microporous layer (MPL) and gas diffusion layer (GDL) of polymer electrolyte membrane fuel cells ...(PEMFCs). Two-phase LB simulations are performed with modeled porous geometries that imitate multilayer porous transport layers (PTLs) consisting of an MPL and a GDL The simulation conditions are closely matched to the actual liquid water transport conditions in the PEMFCs. The results indicate that invasion-percolation processes due to strong capillary effects govern liquid water transport in PEMFCs. In addition, LB simulations are conducted by varying the intrusion thickness of the MPL and the surface wettability of the PTL. The results clearly show that the liquid water content can be reduced in the PTL by employing a thicker MPL and/or more hydrophobic surfaces. The steady-state water distribution is observed to occur more rapidly as the MPL becomes thicker or as the solid surfaces become more hydrophobic. Furthermore, several dynamic liquid water transport behaviors are identified from the results and explained in detail.
The suitable materials, metal nitrides, are a promising class of electrocatalyst materials for a highly efficient oxygen evolution reaction (OER) because they exhibit superior intrinsic conductivity ...and have higher sustainability than oxide-based materials. To our knowledge, for the first time, we report a designable synthesis of three-dimensional (3D) and mesoporous Co
3
N@amorphous N-doped carbon (AN-C) nanocubes (NCs) with well-controlled open-framework structures via monodispersed Co
3
Co(CN)
6
2
Prussian blue analogue (PBA) NC precursors using
in situ
nitridation and calcination processes. Co
3
N@AN-C NCs (2 h) demonstrate better OER activity with a remarkably low Tafel plot (69.6 mV·dec
−1
), low overpotential of 280 mV at a current density of 10 mA·cm
−2
. Additionally, excellent cycling stability in alkaline electrolytes was exhibited without morphological changes and voltage elevations, superior to most reported hierarchical structures of transition-metal nitride particles. The presented strategy for synergy effects of metal-organic frameworks (MOFs)-derived transition-metal nitrides-carbon hybrid nanostructures provides prospects for developing high-performance and advanced electrocatalyst materials.
The connection between marine biogenic dimethyl sulfide (DMS) and the formation of aerosol particles in the Arctic atmosphere was evaluated by analyzing atmospheric DMS mixing ratio, aerosol particle ...size distribution and aerosol chemical composition data that were concurrently collected at Ny-Ålesund, Svalbard (78.5° N, 11.8° E), during April and May 2015. Measurements of aerosol sulfur (S) compounds showed distinct patterns during periods of Arctic haze (April) and phytoplankton blooms (May). Specifically, during the phytoplankton bloom period the contribution of DMS-derived SO42− to the total aerosol SO42− increased by 7-fold compared with that during the proceeding Arctic haze period, and accounted for up to 70 % of fine SO42− particles (< 2.5 µm in diameter). The results also showed that the formation of submicron SO42− aerosols was significantly associated with an increase in the atmospheric DMS mixing ratio. More importantly, two independent estimates of the formation of DMS-derived SO42− aerosols, calculated using the stable S-isotope ratio and the non-sea-salt SO42− ∕ methanesulfonic acid ratio, respectively, were in close agreement, providing compelling evidence that the contribution of biogenic DMS to the formation of aerosol particles was substantial during the Arctic phytoplankton bloom period.
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