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Rigid, solid-state components represent the current paradigm for electronic systems, but they lack post-production reconfigurability and pose ever-increasing challenges to efficient end-of-life recycling. Liquid electronics may overcome these limitations by offering flexible in-the-field redesign and separation at end-of-life via simple liquid phase chemistries. Up to now, preliminary work on liquid electronics has focused on liquid metal components, but these devices still require an encapsulating polymer and typically use alloys of rare elements like indium. Here, using the self-assembly of jammed 2D titanium carbide (Ti3 C2 Tx ) MXene nanoparticles at liquid-liquid interfaces, "all-liquid" electrically conductive sheets, wires, and simple functional devices are described including electromechanical switches and photodetectors. These assemblies combine the high conductivity of MXene nanosheets with the controllable form and reconfigurability of structured liquids. Such configurations can have applications not only in electronics, but also in catalysis and microfluidics, especially in systems where the product and substrate have affinity for solvents of differing polarity.

The accumulation of carbon dioxide (CO2) within enclosed spaces, along with volatile organic compounds, under certain humidity, temperature, and ventilation conditions is associated with detrimental human health symptoms such as fatigue. Color-based chemical sensing is a promising approach to detect CO2 levels relevant to indoor air quality through producing fast, quantifiable output visible to the naked eye. In a prior work, a colorimetric gas sensor was fabricated through synthesizing the metal-organic framework, ZIF-8, as the adsorbent, followed by post-synthetic mixing with a dye, phenol red (PSP), and primary amine, ethylenediamine (ED). While this sensor (termed PSP-ED/ZIF-8) maintained its structural integrity in atmospheric conditions and exhibited an increasing fuchsia-to-yellow color change with increasing CO2 levels in dry environment, the colorimetric response greatly suffered in the presence of humid CO2. In this work, a significantly improved colorimetric CO2 sensor (referred to as ED/PSP:ZIF-8) is accomplished through directly incorporating phenol red in the ZIF-8 metal and linker precursor solutions and then blending with ethylenediamine. MATLAB-generated color distributions and in-situ ultraviolet-visible (UV-Vis) spectroscopic studies quantitatively demonstrate an enhanced colorimetric gas response of ED/PSP:ZIF-8 compared to that of PSP-ED/ZIF-8 across an important range of CO2 for indoor air quality monitoring (500 – 3500 ppm) and across a range of humidity. The new sensor also exhibits high selectivity to CO2 compared to select volatile organic compounds, such as acetone and ethanol, which contribute to human health symptoms experienced indoors. The enhanced performance is attributed to the proposed incorporation of phenol red within ZIF-8, while maintaining the chemical stability of the MOF.

The engineering of atomically-precise nanopores in two-dimensional materials presents exciting opportunities for both fundamental science studies as well as applications in energy, DNA sequencing, and quantum information technologies. The exceptional chemical and thermal stability of hexagonal boron nitride (h-BN) suggest that exposed h-BN nanopores will retain their atomic structure even when subjected to extended periods of time in gas or liquid environments. Here we employ transmission electron microscopy to examine the time evolution of h-BN nanopores in vacuum and in air and find, even at room temperature, dramatic geometry changes due to atom motion and edge contamination adsorption, for timescales ranging from one hour to one week. The discovery of nanopore evolution contrasts with general expectations and has profound implications for nanopore applications of two-dimensional materials.

The colour centre platform holds promise for quantum technologies, and hexagonal boron nitride has attracted attention due to the high brightness and stability, optically addressable spin states and wide wavelength coverage discovered in its emitters. However, its application is hindered by the typically random defect distribution and complex mesoscopic environment. Here, employing cathodoluminescence, we demonstrate on-demand activation and control of colour centre emission at the twisted interface of two hexagonal boron nitride flakes. Further, we show that colour centre emission brightness can be enhanced by two orders of magnitude by tuning the twist angle. Additionally, by applying an external voltage, nearly 100% brightness modulation is achieved. Our ab initio GW and GW plus Bethe-Salpeter equation calculations suggest that the emission is correlated to nitrogen vacancies and that a twist-induced moiré potential facilitates electron-hole recombination. This mechanism is further exploited to draw nanoscale colour centre patterns using electron beams.

The low mass density and high mechanical strength of graphene make it an attractive candidate for suspended-membrane energy transducers. Typically, the membrane size dictates the operational frequency and bandwidth. However, in many cases it would be desirable to both lower the resonance frequency and increase the bandwidth, while maintaining overall membrane size. We employ focused ion beam milling or laser ablation to create kirigami-like modification of suspended pure-graphene membranes ranging in size from microns to millimeters. Kirigami engineering successfully reduces the resonant frequency, increases the displacement amplitude, and broadens the effective bandwidth of the transducer. Our results present a promising route to miniaturized wide-band energy transducers with enhanced operational parameter range and efficiency.

Current graphene-based plasmonic devices are restricted to 2D patterns defined on planar substrates; thus, they suffer from spatially limited 2D plasmon fields. Here, 3D graphene forming freestanding nanocylinders realized by a plasma-triggered self-assembly process are introduced. The graphene-based nanocylinders induce hybridized edge (in-plane) and radial (out-of-plane) coupled 3D plasmon modes stemming from their curvature, resulting in a four orders of magnitude stronger field at the openings of the cylinders than in rectangular 2D graphene ribbons. For the characterization of the 3D plasmon modes, synchrotron nanospectroscopy measurements are performed, which provides the evidence of preservation of the hybridized 3D graphene plasmons in the high precision curved nanocylinders. The distinct 3D modes introduced in this paper, provide an insight into geometry-dependent 3D coupled plasmon modes and their ability to achieve non-surface-limited (volumetric) field enhancements.

The power system of heat pipe cooled nuclear reactor can be divided into dynamic conversion system and static conversion system. Thermoelectric generator (TEG) is a typical static conversion device, which can directly convert heat energy into electric energy. The combination of heat pipe cooled nuclear reactor and TEGs can bring many advantages, such as compact structure, high inherent safety, no auxiliary mechanical equipment and low noise. However, the maximum core temperature could exceed 1 000 K, and ordinary thermoelectric generators can not operate in such high temperature. To solve this problem, the use of segmented thermoelectric generator (STEG) in the power system of heat pipe cooled nuclear reactor is a method worthy of research. STEG can play an important role in the heat pipe cooled nuclear reactor. But there is not enough literature to study the application of STEG in heat pipe cooled nuclear reactor. STEG usually splices two or three thermoelectric materials with the highest power generation efficiency in different temperature ranges. In this way, STEG can obtain a high thermoelectric conversion efficiency in a wide temperature range (usually above 600 K). Therefore, a kind of STEG for heat pipe cooled nuclear reactor was designed. In this paper, a conceptual design of a heat pipe cooled nuclear reactor with STEGs was proposed. The single STEG and single channel model were explored by COMSOL software. A three-dimensional finite element model of STEG’s performance in heat pipe cooled nuclear reactor was established. STEG was designed to compose of bismuth telluride and skutterudite, and its geometric structure and performances were optimized. Numerical simulation was carried out under steady-state conditions to determine the optimal STEG’s geometry. Then, the optimized STEG was connected with the heat pipe to form a single channel model for simulation to explore its performances. When the temperature difference reaches 550 K, the maximum STEGs’ output power reaches 0.374 W, and the maximum conversion efficiency is 15.75%. In single channel model, when the heating power is 300 W, the maximum STEGs’ output power reaches 47.29 W, and the maximum conversion efficiency is 15.63%. The simulation also show that the maximum stress of single STEG and single channel model are 270 MPa and 547.5 MPa, respectively. And the maximum stress appears on the copper conductor near the hot side. This paper could provide a preliminary basis for the numerical simulation of the combination of STEG and heat pipe cooled nuclear reactor. This paper can also be used as a reference for the thermoelectric conversion of heat pipe cooled nuclear reactors.

Herein, we reported the development of a water-soluble conjugated polyelectrolyte (CPE) for efficient CO2 photoreduction under visible light (λ > 420 nm). Bearing a fluorene-benzothiadiazole backbone and imidazolium-functionalized side chains, PFBT-Im exhibits remarkable photocatalytic activity with nearly 100% selectivity and a CO yield of 453.16 μmol g−1 within 4 h, which is 8.6 and 2.5 times larger than those of conjugated polymers grafted with octyl and trimethylammonium side chains, respectively. [ABSTRACT FROM AUTHOR]

The electromagnet module, as a fundamental component providing levitation force for maglev trains, plays a crucial role in ensuring the stability of train operation. However, vibrations can easily occur due to the mechanical coupling between the two suspension points of the electromagnet module. To reveal the inherent instability of the system and the coupling relationship between the state variables, a state-space equation that considers the mechanical coupling between the two suspension points is established. Furthermore, a differential control algorithm based on geometric feature transformation is proposed to mitigate the structural coupling vibration. Simulation experiments are conducted to compare the dynamic characteristics of the system before and after implementing the improvement algorithm under complex conditions. At the same time, the influence of control parameters on electromagnetic vibration was analyzed, focusing particularly on vibrations resulting from parameter mismatch, offering crucial insights for enhancing system stability. Additionally, suspension tests are carried out on the high-speed double bogie test platform in the Key Laboratory of Hunan Province to further validate the effectiveness of the proposed algorithm. The proposed control framework is both effective and concise, making it easy to implement in engineering applications. This research holds significant practical value in improving the stability of maglev trains. [ABSTRACT FROM AUTHOR]

Background The anti-inflammatory effects of budesonide (BUN) and N-acetylcysteine (NAC) attenuate acute lung injury (ALI). The aim of this study was to investigate the effects of combination therapy consisting of BUN and NAC on ALI and the underlying mechanisms. Methods In vitro and in vivo models of ALI were generated by LPS induction. Western blotting was used to detect the expression levels of pyroptosis-related proteins and inflammation-related factors, and RT–qPCR was used to detect the expression of miR-381. Cell proliferation and apoptosis were detected by CCK-8 and flow cytometry, respectively. ELISA was used to detect the levels of inflammation-related factors. HE staining was used to detect lung injury. Results The results showed that LPS effectively induced pyroptosis in cells and promoted the expression of pyroptosis-related proteins (Caspase1, Gasdermin D and NLRP3) and inflammatory cytokines (TNF-α, IL-6 and IL-1β). The combination of BUN and NAC significantly alleviated LPS-induced pyroptosis and inflammation. In addition, the combination of BUN and NAC effectively promoted miR-381 expression. Transfection of miR-381 mimics effectively alleviated LPS-induced pyroptosis and inflammation, while transfection of miR-381 inhibitors had the opposite effect. miR-381 negatively regulates NLRP3 expression. Treatment with a miR-381 inhibitor or pc-NLRP3 reversed the effects of the combination of BUN and NAC. In a mouse model of ALI, the combination of BUN and NAC effectively improved lung injury, while treatment with a miR-381 inhibitor or pc-NLRP3 effectively reversed this effect. Conclusion Overall, this study revealed that BUN + NAC inhibits the activation of NLRP3 by regulating miR-381, thereby alleviating ALI caused by pyroptosis-mediated inflammation. [ABSTRACT FROM AUTHOR]

Integrated capture and photoreduction of diluted CO2 into energy-rich fuels represents an important challenge in renewable energy research and is attracting remarkable attention. In this study, two new benzimidazole-linked conjugated microporous polymers (CMPs), namely TFPA-DAB and TFPT-DAB, have been constructed by the condensation of 3,3′-diaminobenzidine (DAB) with tris(4-formylphenyl)amine (TFPA) and 2,4,6-tris(4-formylphenyl)-1,3,5-triazine (TFPT), respectively. The abundant basic N sites within the polymer network endow both TFPA-DAB (44.82 cm3 g−1) and TFPT-DAB (53.21 cm3 g−1) with high CO2 uptake at 273 K and 1 bar. Initial slope selectivity calculations demonstrated that TFPT-DAB possessed excellent CO2/N2 selectivity of 103 in comparison with TPFA-DAB (85) at 273 K as a result of changing the polymer core from 2,4,6-triphenyl-1,3,5-triazine to triphenylamine. Moreover, TFPT-DAB showed a narrower band gap down to 2.35 eV and better interface charge transfer than TFPA-DAB. Accordingly, under a 1% CO2/N2 atmosphere with water vapor as the electron donor, TFPT-DAB without a cocatalyst exhibited a superior CO production rate (CPR) of up to 178.45 μmol h−1 g−1 with almost 100% reaction selectivity (>420 nm), which is 5 times that of TFPA-DAB (35.31 μmol h−1 g−1) and ranks among the highest of known photocatalysts for gas–solid-phase CO2 reduction to date. This contribution indicates the bright prospect of benzimidazole-linked CMPs for highly efficient photoreduction of low-content CO2 in industrial exhaust. [ABSTRACT FROM AUTHOR]

Transition metal ions (M = Ag+, Cu2+, Co2+, and Cr3+) are surface or homogeneously doped into ZnS via facile cation-exchange reaction, and while Ag+ and Cu2+ doping does not induce sulphur vacancies (Vs) or zinc vacancies (VZn), Co2+ and Cr3+ doping induces Vs. The surface doped catalysts exhibit greatly higher activity than the ZnS and homogenous doped catalysts for H2 evolution and CO2 reduction. The important role of the doping state on affecting the photo-absorption, carrier separation efficiency, and photoreaction kinetics has been systemically investigated and proposed. This work sheds light on the future design and fabrication of high-performance photocatalysts by element doping. [ABSTRACT FROM AUTHOR]