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Negative ions are crucial in various scientific and technological fields, such as antimatter research, interstellar chemistry, accelerator-based radionuclide dating, fusion injection for controlled nuclear fusion, and neurological disease treatment. Thus, producing a large number of negative ions is highly important. Herein, we present the first theoretical evidence of a large fraction of negative-ion formation during the grazing scattering of carbon atoms from a CsI(100) surface. The conversion efficiency of the negative ions reaches ≥86% within a projectile energy range of Ep∈ [5,10] keV. These remarkable results are attributed to large anion and cation polarizations, which lead to an evidently large Mott–Littleton polarization interaction. This interaction lowers the energy defect of valence band electron capture to below 1.8 eV near the surface anion sites, drastically increasing the electron-capture probability. The destruction of negative ions occurs owing to affinity electron detachment via the Coulomb barrier tunneling to the vacuum level during the interactions with surface anion sites along their trajectories. Our results indicate that this collision system can be used to design next-generation negative carbon ion sources for studying the isotope shift of electron affinity and provide insights into electron correlation effects and molecular-level irradiation pathological studies, especially for promoting nerve tissue repair and regeneration through Ep∈ [5,10] keV negative carbon ion irradiation.

Organic piezomaterials have attracted much attention because of their easy processing, lightweight, and mechanic flexibility properties. Developing new smart organic piezomaterials is highly required for new-generation electronic applications. Here, we found a novel organic piezomaterial of organic charge-transfer complex (CTC) consisting of dibenzcarbazole analogue (DBCz) and tetracyanoquinodimethane (TCNQ) in the molecular-level heterojunction stacking mode. The DBCz–TCNQ complex exhibited ferroelectric properties (the saturated polarization of ∼1.23 μC/cm2) at room temperature with a low coercive field. The noncentrosymmetric alignment (Pcspace group) led to a spontaneous polarization of this architecture and thus was the origin of the piezoelectric behavior. Lateral piezoelectric nanogenerators (PENGs) based on the thermal evaporated CTC thin-film exhibited significant energy conversion behavior under mechanical agitation with a calculated piezoelectric coefficient (d31) of ∼33 pC/N. Furthermore, such a binary CTC thin-film constructed single-electrode PENG could show steady-state sensing performance to external stimuli as this flexible wearable device precisely detected physiological signals (e.g., finger bending, blink movement, carotid artery, etc.) with a self-powered supply. This work provides that the polar CTCs can act as efficient piezomaterials for flexible energy harvesting, conversion, and wearable sensing devices with a self-powered supply, enabling great potential in healthcare, motion detection, human–machine interfaces, etc.

Implantable neuroelectronic interfaces have gained significant importance in long-term brain–computer interfacing and neuroscience therapy. However, due to the mechanical and geometrical mismatches between the electrode–nerve interfaces, personalized and compatible neural interfaces remain serious issues for peripheral neuromodulation. This study introduces the stretchable and flexible electronics class as a self-rolled neural interface for neurological diagnosis and modulation. These stretchable electronics are made from liquid metal–polymer conductors with a high resolution of 30 μm using microfluidic printing technology. They exhibit high conformability and stretchability (over 600% strain) during body movements and have good biocompatibility during long-term implantation (over 8 weeks). These stretchable electronics offer real-time monitoring of epileptiform activities with excellent conformability to soft brain tissue. The study also develops self-rolled microfluidic electrodes that tightly wind the deforming nerves with minimal constraint (160 μm in diameter). The in vivosignal recording of the vagus and sciatic nerve demonstrates the potential of self-rolled cuff electrodes for sciatic and vagus neural modulation by recording action potential and reducing heart rate. The findings of this study suggest that the robust, easy-to-use self-rolled microfluidic electrodes may provide useful tools for compatible neuroelectronics and neural modulation.

This article investigates the underwater navigation control of a water–air amphibious multirotor vehicle. We use active disturbance rejection control (ADRC) to construct a tandem-level ADRC motion controller for the water–air multirotor vehicle and introduce particle swarm optimization (PSO) to quickly tune controller parameters. First, the amphibious multirotor vehicle's governing kinematic and dynamic equations are derived. Then, the hydrodynamics of the underwater navigation process is analyzed and estimated. Accordingly, ADRC-based position and attitude controllers are designed and compared with a traditional proportional–integral–derivative (PID) controller and a sliding mode controller (SMC). In addition, PSO is introduced to adjust the gain parameters of the PID, SMC controller, and the parameters of the nonlinear state error feedback law and extended state observer of the ADRC controller. Finally, to verify the stability and robustness of the ADRC controller, simulations are performed under strong external disturbances with a water–air multirotor vehicle. The results demonstrate that controller performance can be improved by introducing PSO to tune the controller parameters and that it is more beneficial for the self-adjacent controller with many control parameters and strong interparameter nonlinearity. ADRC responds faster, rejects external disturbances better, and is more robust than SMC and PID, which permits it to meet the performance requirements of the controller in complex underwater environments.

Due to the wide range of uses for phosphors in lighting and displays, research on narrow-band luminescent phosphors has recently received significant interest. In this work, Eu2+-activated Sr2BN2Cl phosphor has been successfully synthesized. Sr2BN2Cl:Eu2+shows a wide absorption band in the UV region and exhibits a narrow-band emission peaking at 450 nm with a full width at half-maximum of ∼60 nm. More significantly, excellent thermal stability was discovered, which showed it still retained 87.4 and 100% of room-temperature intensity at 150 and 250 °C, respectively. The rigid skeleton formed by the co-edge connection of Sr(N, Cl)6octahedra and defects in the crystal are responsible for the excellent thermal stability of the phosphor. In addition, two types of white-led devices have been prepared to test this phosphor for illumination and display applications. The former shows low correlated color temperature (CCT = 3190 K) and a high color rendering index (CRI = 92.0). The latter shows that using Sr2BN2Cl:Eu2+, β-sialon:Eu2+, and K2SiF6:Mn4+together for backlit displays can cover 73.3% of the NTSC area, which is comparable to commercial BaMgAl10O17:Eu2+phosphors. These findings suggest that the blue phosphor Sr2BN2Cl:Eu2+will be a promising choice for lighting and backlight displays.

To date, mechanistic treatments targeting the initial cause of Parkinson's disease (PD) are limited due to the underlying biological cause(s) been unclear. Endosomes and their associated cellular homeostasis processes have emerged to have a significant role in the pathophysiology associated with PD. Several variants within retromer complex have been identified and characterised within familial PD patients. The retromer complex represents a key sorting platform within the endosomal system that regulates cargo sorting that maintains cellular homeostasis. In this review, we summarise the current understandings of how PD-associated retromer variants disrupt cellular trafficking and how the retromer complex can interact with other PD-associated genes to contribute to the disease progression.

Material Jetting (MJ) process is an additive manufacturing process that is able to produce structures with high resolutions. The performance and quality of the MJ printed parts extensively rely on the droplet morphology and behavior. However, obtaining consistent and stable droplet morphology and behavior is difficult because the droplets are very sensitive to different material and process parameters. Testing/studying all these parameter combinations is time-consuming due to the high-experimental and high-computational costs. We thus study the prediction of droplet behaviors under different material and process parameters. To achieve this, we propose to leverage the underlying relationships shared across droplet evolution behaviors with diverse material and process parameters (referred to as “cross-linked” relationship hereafter) as well as the spatial–temporal relationships of droplet evolution, and capture these with the Network of Tensor Time Series (NET3). The distinct droplet behaviors are regarded as co-evolving time series (i.e., Tensor Time Series (TTS)) since they share the same physics principles. In particular, we capture the cross-linked and spatial relationships of TTS by the Tensor Graph Convolutional Network (TGCN), and capture the temporal relationship of TTS by the Tensor Recurrent Neural Network (TRNN), respectively. The features from TGCN and TRNN are passed to Multilayer Perceptron (MLP) for predicting future droplet behaviors. The proposed methodology is demonstrated with simulated (i.e., physics-based models) and experimental (i.e., MJ printing observation with vision system) droplet evolution videos and is able to accurately and efficiently make predictions for seen (i.e., forecasting for a future time) and unseen (i.e., new droplet evolution sequence prediction) material/process parameters.

ABSTRACTIn this article, we discuss the emission of visible light (400–900 nm) by a monolithically integrated silicon p-n junction under reverse bias. Silicon light emitting devices (Si-LEDs) could be designed and realized utilizing the standard complementary metal oxide semiconductor (CMOS) technology. Increased electroluminescence from the three-terminal MOS-like structure is observed, with the approach of carrier energy and momentum engineering design. Because Si-LEDs, waveguides, and photodetectors (Si) can be integrated on a single chip, a small microphotonic system could be realized in the CMOS integrated circuitry standard platform. The results can be substantially utilized for realizing a complete on-chip optical link.

Two amorphous lumps of a black material with a combined weight of c. 1kg were recovered during rescue excavations at the Mausoleum M1 of the King of Jiangdu, located at Dayun Hill, Jiangsu Province, China, and dated to the Western Han Period (202 BC–8AD). This paper reports the analysis of this material by Fourier-transform infrared spectroscopy, gas chromatography and gas chromatography–mass spectrometry. Through comparison with modern reference samples, the archaeological material is identified as beeswax. Based on archaeological and documentary evidence, it is argued that this provides direct evidence for the early use of beeswax and could constitute the earliest use of beeswax as fuel for lamps in China.

The article discusses artefacts, taken from the collection of the Nanjing Museum in Nanjing, China, relating to the Han Dynasty, particularly focusing on tombs of the Jiangdu kingdom. It addresses the influence of funerary beliefs on Han Dynasty relics, the role of pottery in the Han Dynasty, and Jiangdu kingdom bronze artefacts.

Surface of Y3Al5O12:Ce3+Phosphor was modified by wet etching in 40% NH4F+CH3COOH(1:1) solution for 5 h. SEM results show that smooth surface of phosphor particles turn rough, and edge angles are less sharp as before. PL determinations indicate that backscattering loss of the excited light reduces by 3.9% and emission power is enhanced by 10.7%. Meanwhile, after the surface modification, YAG phosphor presents a lower temperature decay rate of 1.2% at 373 K, which is well explained by the configurational coordinate diagram. Therefore, this method can greatly enhance the efficient of light conversion, extraction and stabilization of pc-LED.