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Constructing the desired long-range dual sites to enhance the C–C bond-cleavage and CO-tolerate ability during ethanol oxidation reaction is of importance for further applications. Herein, the concept of holding atomically dispersed NiOx cluster supported on Pt-based high-index facets (NiOx/Pt) is proposed to build O-bridged Pt–Ni dual sites. Strikingly, the obtained NiOx/Pt dual sites show 4.97 times specific activity higher than that of commercial Pt/C (0.35 ​mA ​cm−2), as well as outstanding CO-tolerance and durability. The advanced electrochemical in-situ characterizations reveal that the NiOx/Pt can accelerate rapid dehydroxylation and C–C bond-cleavage over the Pt–Ni dual sites. Theoretical calculations disclose that the atomically dispersed NiOx species can lower the adsorption/reaction energy barriers of intermediates. This tactic provides a promising methodology on regulating the surface synergistic sites via engineering atomically dispersed oxide site.

Abstract Circumventing the conventional two-electron oxygen reduction pathway remains a great problem in enhancing the efficiency of H2O2 photosynthesis. A promising approach to achieve outstanding photocatalytic activity involves the utilization of redox intermediates. Here, we engineer a polyimide aerogel photocatalyst with photoreductive carbonyl groups for non-sacrificial H2O2 production. Under photoexcitation, carbonyl groups on the photocatalyst surface are reduced, forming an anion radical intermediate. The produced intermediate is oxidized by O2 to produce H2O2 and subsequently restores the carbonyl group. The high catalytic efficiency is ascribed to a photocatalytic redox cycle mediated by the radical anion, which not only promotes oxygen adsorption but also lowers the energy barrier of O2 reduction reaction for H2O2 generation. An apparent quantum yield of 14.28% at 420 ± 10 nm with a solar-to-chemical conversion efficiency of 0.92% is achieved. Moreover, we demonstrate that a mere 0.5 m2 self-supported polyimide aerogel exposed to natural sunlight for 6 h yields significant H2O2 production of 34.3 mmol m−2.

Mitophagy is the cellular process to selectively eliminate dysfunctional mitochondria, governing the number and quality of mitochondria. Dysregulation of mitophagy may lead to the accumulation of damaged mitochondria, which plays an important role in the initiation and development of tumors. Mitophagy includes ubiquitin-dependent pathways mediated by PINK1/Parkin and non-ubiquitin dependent pathways mediated by mitochondrial autophagic receptors including NIX, BNIP3, and FUNDC1. Cellular mitophagy widely participates in multiple cellular process including metabolic reprogramming, anti-tumor immunity, ferroptosis, as well as the interaction between tumor cells and tumor-microenvironment. And cellular mitophagy also regulates tumor proliferation and metastasis, stemness, chemoresistance, resistance to targeted therapy and radiotherapy. In this review, we summarized the underlying molecular mechanisms of mitophagy and discussed the complex role of mitophagy in diverse contexts of tumors, indicating it as a promising target in the mitophagy-related anti-tumor therapy.

Tartronic acid is known for its potential to inhibit sugar-to-lipid conversion in the human body, leading to weight loss and fat reduction. This compound is predominantly found in cucumbers and other cucurbit crops. Therefore, cultivating cucumbers with high tartronic acid content holds significant health implications. In this study, we assessed the tartronic acid content in 52 cucumber germplasms with favorable overall traits and identified 8 cucumber germplasms with elevated tartronic acid levels. Our investigation into factors influencing cucumber tartronic acid revealed a decrease in content with fruit development from the day of flowering. Furthermore, tartronic acid content was higher in early-harvested fruits compared to late-harvested ones, with the rear part of the fruit exhibiting significantly higher content than other parts. Foliar spraying of microbial agents increased tartronic acid content by 84.4%. This study provides valuable resources for breeding high tartronic acid cucumbers and offers practical insights for optimizing cucumber production practices.

Photocatalysis is accepted as a promising method for selective oxidative coupling of amine to imine. However, owing to the rapid dehydrogenation of the generated imine intermediate of α‐amino hydrogen to butyronitrile, it remains a huge challenge to fabricate an exquisite catalyst with enhanced conversion and selectivity. Herein, a novel heterogeneous catalyst (Bpy‐CoCl2/CNCOOH) is developed, where carboxyl functionalized carbon nitride (CNCOOH) serves as a substrate material and couples with highly efficient cobalt‐aminopyridine (Bpy‐CoCl2) molecular catalyst through covalent bonding. The catalyst not only effectively facilitates the transfer of photogenerated charges, but also generates mildly oxidatively active species of superoxide radicals, which can effectively oxidize various functionalized benzylamines to corresponding imines in the presence of oxygen with at least 78.5% conversion and >99% selectivity using O2 as oxygen source, especially for the unmodified benzylamine with >99% conversion and >99% selectivity. This unique combination of a selective molecular catalyst and a simple and robust semiconducting material open new avenues for the selective oxidative coupling of amines.

With the improvement in the level of science and technology and the improvement of people’s living standards, the functions of traditional manual wheelchairs have been unable to meet people’s living needs. Therefore, traditional wheelchairs have been gradually replaced by smart wheelchairs. Compared with traditional wheelchairs, smart wheelchairs have the characteristics of light operation and faster speed. However, when driving on some complex road surfaces, the vibration generated by the bumps of the motorcycle will cause damage to the human body, so wheelchairs with good electric power and stability can better meet the needs of people and make up for their travel needs. Based on the traditional vehicle stability analysis method, the mathematical theory of roll stability and pitch stability of the wheelchair–human system was established. We built a multi-body dynamics model with human skeleton and joint stiffness based on the multi-body dynamics method. The functioning of the wheelchair–human system was simulated and analyzed on the ditch, step, and combined road. The acceleration and Euler angle changes of the human head, chest, and wheelchair truss position were obtained, and the data results were analyzed to evaluate the stability and comfort of the system. Finally, a wheelchair test platform was built, and the road driving test was carried out according to the simulation conditions to obtain the system acceleration and angle data during the driving process. The simulation analysis was compared to verify the accuracy of the multi-body dynamics method, and the stability and comfort of the system were evaluated.

The use of hollow-core anti-resonant fiber (HC-ARF) as a transmission medium for the terahertz (THz) frequency range is attracting increasing attention from researchers. This paper introduces a low-loss, high birefringence anti-resonant fiber. The proposed structure achieves a maximum birefringence of 2.72 × 10−3 around 1 THz and maintains a birefringence above the 10−3 level over a wide frequency band (0.7∼1.12 THz). It has a minimum loss of 0.2 dB/m and a minimum bend radius of 0.3 m, and the paper validates that this structure has good manufacturing error tolerance. Furthermore, three methods for introducing high birefringence into low-loss ARFs are proposed and three structures are selected for verification. These findings contribute to the development of more efficient and reliable THz transmission systems.

This article presents the recent developments in the field of evaluation of the breakdown performance and remaining lifetime of XLPE insulation and analyzes the accuracy of existing lifetime prediction models through experiments. The effects of the crystalline morphology, cable thickness and sampling location of XLPE insulation on the evaluation of short-term breakdown performance are reviewed in the context of the experiments. The study reviews the application of the Ramu, Simoni, and Ramu multi-stress lifetime prediction models and explores the other remaining lifetime prediction models under the combined electrothermal stresses which are applicable to XLPE insulation. Finally, this paper recommends the most effective engineering evaluation methods and provides suggestions for improving the electrical performance of XLPE insulation for high-voltage cables.

Vanadium is recognized as a potentially dangerous pollutant following closely behind lead, mercury and arsenic. Vanadium removal from wastewater prior to discharge is essential. In this work, an amorphous hydrated chromium oxide was prepared and its vanadium adsorption ability studied. As prepared, the hydrated oxide showed high efficiency in vanadium adsorption – e.g., from 300 to 0.75 mg-V·L−1. The effects of pH, adsorbent dosage, temperature, adsorption time and the presence of other ions on the vanadium removal rate were investigated, and optimal parameters determined. Dynamic adsorption results showed that pseudo-second-order kinetics could be used to interpret the kinetic curve and that the process was that of chemisorption. The Langmuir isotherm was found to fit the adsorption behavior well. HIGHLIGHTS An amorphous hydrated chromium oxide was used for vanadium adsorption.; The concentration of vanadium ions could be decreased from 300 to 0.75 mg·L−1.; Effects of parameters and adsoption kinetics and isotherms were studied.; Common co-existing ions show little influence on the adsorption efficiency.;

The selective biomass conversion of 5‐hydroxymethylfurfural (HMF) to 2,5‐diformylfurane (DFF) through photocatalysis is of immense importance and has attracted much interest recently. However, its selectivity and conversion are still limited at present due to the lack of efficient photocatalysts to controllably activate the alcohol hydroxyl groups. Herein, Nb2O5/g‐C3N4 type‐II heterojunction photocatalysts to restrain the over‐oxidation are developed, which successfully adjust the active oxygen species and enhance the separation and transfer of photoexcited carriers. The system achieves selective oxidation of HMF to DFF with high selectivity (>99%) and conversion (53%) via the inhibition of hydroxyl radicals (·OH) production arising from the decomposition of H2O2. Moreover, h+ is the main active species for photocatalytic selective oxidation of HMF, and ·O2− is the second for that. Herein, it offers an effective strategy to effectively improve the high‐selective conversion of biomass derivatives into high‐value‐added products.

An exceptionally high-performance, high-birefringent photonic crystal fiber (PCF) is meticulously designed. The core design features a unique arrangement in which the central row of circular air holes is substituted by three rows of smaller circular holes. Subsequently, the middle row is adjusted to achieve various rectangular mode field configurations. With the optimized structure parameters, the birefringence of the PCF can reach 3.57 × 10−2 at a wavelength of 1.55 μm. The confinement loss is as low as 8.4 × 10−6 dB/m. The nonlinear coefficient is up to 41 W−1·km−1. The dispersion is relatively flat within the range from 1.3 μm to 1.9 μm. These remarkable characteristics render the proposed PCF a strong candidate for applications in polarization preservation, dispersion compensation, wideband supercontinuum generation, and other related fields.

We propose a novel demodulation scheme based on measuring interference fringe visibility and demonstrate it using a typical Michelson interferometer (MI) configuration. The key component to achieve the scheme is a section of highly birefringent fiber (HBF) spliced into the sensing arm to function as the sensing element. The optical path difference (OPD) leads to interference fringes, while the birefringence of the HBF results in a visibility envelop. It is possible to detect measurands associated with birefringence through measuring the visibility, which is attributed to a flexible use of the fundamental principle of interferometry. As one of the potential applications, temperature sensing employing the MI configuration is performed. Moreover, the technique has the advantage of being immune to element instabilities, such as power fluctuation of the light source, phase shift of the reference arm, noise of the photo detector, and wavelength shift of the optical spectrum analyzer (OSA). This work may provide an alternative method to achieve high precision interferometry with low cost.

Objective: To accurately achieve distal contact force, a novel temperature-compensated sensor is developed and integrated into an atrial fibrillation (AF) ablation catheter. Methods: A dual elastomer-based dual FBGs structure is used to differentiate the strain on the two FBGs to achieve temperature compensation, and the design is optimized and validated by finite element simulation. Results: The designed sensor has a sensitivity of 90.5 pm/N, resolution of 0.01 N, and root–mean–square error (RMSE) of 0.02 N and 0.04 N for dynamic force loading and temperature compensation, respectively, and can stably measure distal contact forces with temperature disturbances. Conclusion: Due to the advantages, i.e., simple structure, easy assembly, low cost, and good robustness, the proposed sensor is suitable for industrial mass production.

A facile post-synthetic strategy was developed to functionalize the preformed hollow mesoporous silica spheres by encapsulating the molybdenum dioxide (MoO2) nanoparticles inside the interior cavity. Hollow mesoporous silica spheres were prepared and employed as carriers, and the encapsulation of MoO2 nanoparticles was achieved through a one-pot hydrothermal protocol. After characterization, the encapsulated MoO2 nanoparticles were certified to be ultrafine and highly dispersed, which greatly promoted the catalytic activity. The as-prepared catalysts were utilized in epoxidation of alkenes and exhibited as a promising catalyst in this reaction. After reacting for 10 h, the optimal catalyst MoO2@SiO2-1 achieved a conversion above 95% and selectivity above 95%, respectively. Moreover, the catalysts also exhibited good reusability, conversion of 78% and selectivity of 89% (reaction time 4 h) were still obtained after recycling for 5 times. Meanwhile, the employed facial and efficient hydrothermal approach could be expanded to other molybdenum modified heterogeneous catalysts in various applications. Keywords: Post-synthesis, Ultrafine, Molybdenum dioxide, Alkene, Epoxidation

We report the strong coupling between plasmonic surface lattice resonances (SLRs) and photonic Fabry-Pérot (F-P) resonances in a microcavity embedded with two-dimensional periodic array of metal-insulator-metal nanopillars. For such a plasmonic-photonic system, we show that the SLR can be strongly coupled to the F-P resonances of both the odd- and even orders, and that the splitting energy reaches as high as 153 meV in the visible regime. Taking advantage of the strong coupling, the resulted high-energy upper polariton has similar characteristics as the plasmonic SLR, but the quality factor is almost twice of that of the SLR. We expect that this work will provide a new scheme for strong coupling between plasmonic and photonic modes, and will point to a new direction to improve the quality factor of SLRs.

The various advantages of organic polymer monoliths, including relatively simple preparation processes, abundant monomer availability, and a wide application range of pH, have attracted the attention of chromatographers. Organic polymer monoliths prepared by traditional methods only have macropores and mesopores, and micropores of less than 50 nm are not commonly available. These typical monoliths are suitable for the separation of biological macromolecules such as proteins and nucleic acids, but their ability to separate small molecular compounds is poor. In recent years, researchers have successfully modified polymer monoliths to achieve uniform compact pore structures. In particular, microporous materials with pores of 50 nm or less that can provide a large enough surface area are the key to the separation of small molecules. In this review, preparation methods of polymer monoliths for high-performance liquid chromatography, including ultra-high cross-linking technology, post-surface modification, and the addition of nanomaterials, are discussed. Modified monolithic columns have been used successfully to separate small molecules with obvious improvements in column efficiency. Keywords: High-performance liquid chromatography, Polymer monolith, Preparation methods, Small molecules

We numerically demonstrate a scheme of optofluidic sorting of nanoparticles on a silicon-based lab-on-a-chip system, with reconfigurable and multilevel sorting size thresholds. Size-dependent sorting of nanoparticles originates from the size-dependent distribution of trapping potential wells, which determines whether a nanoparticle can jump back and forth between parallel waveguides in weakly coupling condition. In numerical modeling, we find that it is easier for larger ones to transfer and the size threshold is power ratio dependent. By setting a thermal tuning ring-assisted Mach-Zehnder interferometer ahead, we can adjust effectively the input power ratio of the parallel waveguides as well as the potential well distribution across them, working as a thermal tuning reconfigurable sorting unit. Consequently, a tree cascaded unit with different thresholds is also presented to be a reconfigurable multilevel sorting unit. The proposed design offers a simple and ultracompact scheme for the reconfigurable and multilevel optofluidic sorting of nanoparticles on thermo-optofluidics chip for the first time.

A photonic crystal fiber (PCF) with high relative sensitivity was designed and investigated for the detection of chemical analytes in the terahertz (THz) regime. To ease the complexity, an extremely simple cladding employing four struts is adopted, which forms a rectangular shaped core area for filling with analytes. Results of enormous simulations indicate that a minimum 87.8% relative chemical sensitivity with low confinement and effective material absorption losses can be obtained for any kind of analyte, e.g., HCN (1.26), water (1.33), ethanol (1.35), KCN (1.41), or cocaine (1.50), whose refractive index falls in the range of 1.2 to 1.5. Besides, the PCF can also achieve high birefringence (∼0.01), low and flat dispersion, a large effective modal area, and a large numerical aperture within the investigated frequency range from 0.5 to 1.5 THz. We believe that the proposed PCF can be applied to chemical sensing of liquid and THz systems requiring wide-band polarization-maintaining transmission and low attenuation.