Germanium, located in the group IVA, is a superior metalloid semiconductor material and has homologous properties to the congener element of silicene. However, the nonlinear properties of 2D ...germanium nanosheets in broadband (from ultraviolet to near-infrared) were rarely studied. From this perspective, in this work, we successfully prepared 2D germanium nanosheets by the liquid-phase exfoliation method and explored the nonlinear behavior of germanium nanosheets through the open aperture Z-scan technique. The experimental results proved that 2D germanium nanosheets exhibited excellent nonlinear optical potential in the infrared band. Our research is of great significance to inspire people to research germanium-like semiconductor materials and strengthen the nonlinear application of germanium.
•Successfully prepared 2D germanium nanosheets and realized characterizations.•The NLA properties of 2D germanium nanosheets were studied through the open aperture Z-scan technique in a broadband.•Demonstrated the excellent nonlinear potentials and values of 2D germanium nanosheets in the infrared band.
Liquid cooling strategies such as cold plates have been widely employed as an effective approach for battery thermal management systems (BTMS) due to their high cooling capacity and low power ...consumption. The structural design of the cold plates is the key factor that directly determines the thermal performance of the liquid cooling system. In this study, seven Z-type parallel channel cold plate and two novel cross-linked channel cold plate designs are proposed for the cooling of high-power lithium-ion batteries using two different cooling strategies. The average battery temperature, battery temperature uniformity and energy consumption of all designs are firstly analyzed holistically by three-dimensional conjugated simulation under the scheme of continuous cooling. Two selected designs that demonstrated superior performance (i.e., a Z-type parallel channel cold plate with 8-branches and an improved cross-linked channel design) are further analyzed to explore their integrative performance under different cooling schemes. The results show that within a battery temperature limit of 40 °C, employing the delayed cooling strategy can save 23% energy consumption compared to the continuous cooling strategy. Besides, the cold plate with an improved cross-linked channel configuration requires 13% less pumping power and provides a better temperature uniformity than the Z-type parallel channel cold plate with 8-branches. These results are of great significance to advance the cooling design of BTMS.
HfO2-based ferroelectric field-effect transistors (FeFETs) are regarded as one of the most promising non-volatile memory technologies in the future. However, the charge trapping phenomenon during the ...program/erase operation is still a challenge. In this work, we comprehensively investigate the behaviors of semiconductor/insulator interface charge trapping in HfO2-based FeFETs. Through analyzing the effects of the spatial distribution of interface traps and the polarization switching speed, the coupling effects of semiconductor/insulator interface charge trapping and polarization switching are recognized. We also find that the band tail state traps have much less influence on the electrical characteristics of the FeFETs than the deep level state traps. Through engineering the devices with band tail state traps with concentrations as small as possible, the influences of charge trapping could be effectively suppressed. Moreover, the gate voltage (VG) scanning rate has a significant influence on the interface charge trapping process due to the time dependent change of ferroelectric polarization. The largest memory window could be obtained by carefully choosing the VG scanning rate of the FeFETs based on the polarization switching speed. This work represents a key step for realizing highly reliable HfO2-based FeFETs.
Thermochemical heat storage has attracted significant attention in recent years due to potential advantages associated with very high-energy density at the material scale and its suitability for ...long-duration energy storage because of almost zero loss during storage. Despite the potential, thermochemical heat storage technologies are still in the early stage of development and little has been reported on thermochemical reactors. In this paper, our recent work on the charging and discharging behavior of a fixed-bed thermochemical reactor is reported. Silica gels were used as the sorbent for the experimental work. An effective model was established to numerically study the effect of different charging conditions on the discharging behavior of the reactor, which was found to have a maximum deviation of 10.08% in terms of the root mean square error compared with the experimental results. The experimentally validated modelling also showed that the discharging temperature lift increased by 5.84 times by changing the flow direction of the air in the discharging process when the charging level was at 20%. At a charging termination temperature of 51.25 °C, the maximum discharging temperature was increased by 2.35 °C by reducing the charging flow velocity from 0.64 m/s to 0.21 m/s. An increase in the charging temperature and a decrease in the air humidity increased the maximum discharging outlet temperature lift by 3.37 and 1.89 times, respectively.
VISTA (V-domain Ig suppressor of T cell activation) is a novel immune checkpoint protein and represents a promising target for cancer immunotherapy. Here, we report the design, synthesis, and ...evaluation of a series of methoxy-pyrimidine-based VISTA small molecule inhibitors with potent antitumor activity. By employing molecular docking and microscale thermophoresis (MST) assay, we identified a lead compound A1 that binds to VISTA protein with high affinity and optimized its structure. A4 was then obtained, which exhibited the strongest binding ability to VISTA protein, with a K D value of 0.49 ± 0.20 μM. In vitro, A4 significantly activated peripheral blood mononuclear cells (PBMCs) induced the release of cytokines such as IFN-γ and enhanced the cytotoxicity of PBMCs against tumor cells. In vivo, A4 displayed potent antitumor activity and synergized with PD-L1 antibody to enhance the therapeutic effect against cancer. These results suggest that compound A4 is an effective VISTA small molecule inhibitor, providing a basis for the future development of VISTA-targeted drugs.
Metal halide perovskites (MHPs) have excellent characteristics and present great potential in a broad range of applications such as solar cells, light‐emitting diodes, and photodetectors. However, ...the light stability of devices remains an unresolved issue and has received great research attention. Under light illumination, MHPs exhibit various anomalous phenomena, such as photoluminescence (PL) enhancement, defect curing, PL blinking, and phase segregation. These phenomena are commonly considered intimately correlated with the performance and stability of MHP devices. In recent years, significant efforts have been made experimentally and theoretically toward understanding the physical origins of these anomalous effects. However, most research focuses on negative effects while the positive effects are mostly ignored. Herein, the positive effects and the negative effects of light soaking in MHPs are systematically discussed with a classification of the correlated physical mechanisms by specifically focusing on variation occurring in timescale from second to hour, corresponding to the unique ionic–electronic interaction. This intends to provide a new insight into ion effects on excellent properties of perovskites, and deep physical understanding of charge‐carrier and ion dynamics in perovskite, and theoretical guidelines for the fabrication of high‐quality and stability perovskite‐based photovoltaic and photoelectric devices.
For the first time, light soaking effects are separated into positive and negative effects simultaneously occurring in halide perovskites. The positive effects are correlated with the lattice/sublattice effect, while the negative effects are ascribed to the charge and defect effects of mobile ions. The apparent effect is determined by the intensity of illumination and nature of the material.
•The anterior cingulate cortex and right anterior insula showed disrupted functional connectivity in patients with rTLE.•The anterior cingulate cortex and bilateral anterior insula exhibited ...disrupted effective connectivity in patients with rTLE.•Aberrant modulation of the SN participated in attention deficits in patients with rTLE.
The salience network (SN) acts as a switch that generates transient control signals to regulate the executive control network (ECN) and the default mode network (DMN) and has been implicated in cognitive processes. Temporal lobe epilepsy (TLE) is usually accompanied by different types of cognitive deficits, but whether it is associated with dysfunctional connectivity of the SN remains unknown. To address this, thirty-six patients with right TLE (rTLE) and thirty-six healthy controls (HCs) were recruited for the present study. All of the participants were subjected to attention network test (ANT) and resting-state functional resonance imaging (rs-fMRI) scanning. The patient group showed deficits in attention performance. Moreover, the functional connectivity (FC) and effective connectivity (EC) were analyzed based on key SN hubs (the anterior cingulate cortex (ACC) and the bilateral anterior insula (AI)). When compared with those in the HC group, the ACC showed increased FC with the left middle frontal gyrus and the left precentral gyrus, and the right AI showed decreased FC with the right precuneus and the right superior occipital gyrus in the patient group. The EC analysis revealed an increased inflow of information from the left middle temporal gyrus to the ACC and the right AI and an increased outflow of information from the bilateral AI to the left middle frontal gyrus. Furthermore, in the correlation analysis, the abnormal EC from the right AI to the left middle temporal gyrus was positively correlated with the executive control effect. These findings demonstrated aberrant modulation of the SN in rTLE, which was particularly characterized by dysfunctional connectivity between the SN and key brain regions in the DMN and ECN. Elucidation of this effect may further contribute to the comprehensive understanding of the neural mechanisms of the SN in regard to attention deficits in patients with TLE.
Tungsten, a group VIB transition metal with an atomic number of 74, has been continuously excavated and studied to further its applications in the industrial and military fields. However, research on ...the nonlinear optical properties of the transition metal tungsten is rare, which gives us new research impetus. Hence, in this work, the nonlinear optical properties of 2D tungsten nanosheets (fabricated by the LPE method) were explored by employing the open aperture Z-scan technique with broadband wavelengths for the first time to the best of our knowledge. The results demonstrate that 2D tungsten nanosheets possess excellent nonlinear optical values in the ultraviolet band. Our research is of great significance in strengthening the nonlinear optical applications of tungsten and inspiring people to dig deeper into transition metal elements.
The NLA properties of 2D tungsten nanosheets were explored by the open aperture Z-scan technique. The results demonstrated their excellent NLA values in the ultraviolet band, which could draw people's attention to transition metal elements.
Activated coke is considered to be one of the promising CO
2
adsorbents. It could be prepared using coals by a single-step method, but the physical properties and CO
2
adsorption performance of the ...prepared activated coke were significantly different when different ranks of coals were used as the raw materials. In this study, a single-step rapid pyrolysis activation method based on entrained-flow bed was proposed to prepare powdered activated coke (PAC) for CO
2
adsorption. Six typical coals covering lignite, bituminous coal and anthracite were selected as raw material to prepare PACs by the proposed method. The pore structure, surface morphologies and surface functional groups of the prepared PACs were characterized and the yields were calculated. The CO
2
adsorption capacities and adsorption selectivity for CO
2
/N
2
were determined. Results show that the PAC prepared from lignite had the maximum specific surface area of 479 m
2
/g, the most abundant oxygen-containing functional groups and the highest CO
2
adsorption capacity of 3.35 mmol/g at 0°C and 1.2 bar. The physical properties and CO
2
adsorption performance of PACs prepared using bituminous coals were greatly affected by the caking property. The PACs prepared using non-caking/weak-caking bituminous coals, such as Zhundong coal and Jinjie coal had good physical properties and CO
2
adsorption performance, while those prepared using strong-caking coals had poor physical properties and CO
2
adsorption performance. The yields were higher than those of PACs prepared from lignite. The PAC prepared using anthracite had the similar physical properties and CO
2
adsorption performance to PAC prepared using medium-caking bituminous coal, but the yield of 72.17% was the most. It could provide references and basic support for the selection of coal for rapid preparation of coal-based adsorbents related to CO
2
adsorption by the single-step method.
