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Recently, tunable metagratings have attracted substantial attention in manipulating the diffraction of electromagnetic waves with considerable flexibility, but they are usually limited to inherent ohmic loss due to the metal layers. The all-dielectric schemes can address this issue, but its design and optimization remain challenging in the terahertz regime, especially in the 6G communication window. In this work, an all-dielectric tunable terahertz metagrating is demonstrated in theoretical and experimental investigations. The metagrating operating in the 6G communication window bends the electromagnetic waves beam into the T

Multi-element alloy doped diamond-like carbon (DLC) films were coated using sputtering with a (AlCrNbSiTiV) target. TEM and XRD results indicated DLC film had an amorphous compound feature incorporating poly-crystalline phases around the face-center-cubic structure, which were embedded into the amorphous carbon matrix. The Raman spectra and mechanical characteristics of the DLC film sample were associated with concentration changes in the carbon and the multi-element alloy doped in the DLC films, which depended on the DC power. This investigation indicated that improved mechanical properties, including hardness and the elastic recovery rate, can be obtained from the multi-element alloy doped DLC film coated with proper DC sputtering power. These results demonstrated a proper DC power modifies the structure of multi-element alloy doped DLC film and improves its mechanical performance. This study should pave the way for the development of DLC film and elevate its application in various industries.

A special wake-up effect from antiferroelectric-like to ferroelectric (AFE-FE) characteristics in HfxZr1−xO2 thin films has been discussed intensively in terms of endurance performance enhancement. However, its physical origin and general impact on endurance remain unclear. In this work, the influence of various process parameters on the AFE-FE wake-up effect as well as on endurance performance and the material changes during AFE-FE wake-up are systematically studied. It is found that various parameters induce the AFE-FE wake-up effect and enhance endurance performance in the same way with enhancing tetragonal phase formation in HfxZr1−xO2 films, and the cycles of wake-up are universally associated with those of total endurance. In addition, via synchrotron-based grazing incidence x-ray diffraction, a tetragonal-orthorhombic-monoclinic phase transition is observed during AFE-FE wake-up. On the basis of these results, a correlation among crystalline composition, the AFE-FE wake-up effect, and the endurance performance of HfxZr1−xO2 thin films is established. This provides a clear guideline to a viable solution for the high endurance of HfxZr1−xO2 FE memory devices via crystal phase engineering.

Maintaining layer-like features and regulating V atoms will be important directions to improve the performance of NaxV2(PO4)2FO2.

Emerging voltage reference generators (VRGs) are of great demand for low-power applications in recent years. However, keeping good linearity for VRGs in deep submicrometer process is still challenging. Negative capacitance field-effect transistor (NCFET) is an emerging device, which has been found with a negative differential resistance (NDR) phenomenon and has the potential to be applied in VRGs to optimize their linearity. Hence, the feasibility of using NCFET in an emerging ultralow-power (ULP) VRG is studied in this work. An empirical formula to describe NCFET’s NDR is proposed and verified by simulation through a compact SPICE model based on the Landau–Khalatnikov (LK) equation. By adjusting the strength of NDR of NCFET, its output differential resistance can be changed and cancel out the positive differential resistance (PDR) of CMOS transistor. Therefore, the proposed NCFET-based VRG achieves higher linearity. The simulation results show that the line regulation of the NCFET-based VRG decreases from 2.25%/V to 0.21%/V ( $10\times $ ).

It is well known that Glycyrrhetnic acid (GA) has significant liver-targeting and anti-inflammatory effects. Syringopicroside (SYR) and Hydroxytyrosol (HT), the active components of the Chinese herb Syringa oblata Lindl, have earned great reputation for their potential in preventing or treating viral hepatitis type B. Therefore, we loaded SYR and HT into GA-conjugated PEG-PLGA, so that they could target the liver in additional to exerting their own pharmacological effects in a synergistic. However, the in vivo targeting and the low bioavailability of SYR and HT pose a huge challenge. Therefore, we synthesized GA-conjugated multi-component nano-drug delivery system (SH-GPP). SH-GPP had a regular spherical shape with a uniform size distribution of 110.5 ± 3.18 nm. We further evaluated the effects of SH-GPP in vitro and in vivo. In the in vivo experiment, we evaluated the following parameters: the serum ALT and AST values; liver tissue homogenate MDA and SOD; HE staining of the pathological liver sections; and the liver coefficient. In the in vitro studies, the following parameters were evaluated: cellular uptake of SH-GPP; wound healing/scratch assay; cellular apoptosis; cell cycle; HBsAg; and HBeAg content. SH-GPP had better anti-hepatitis B effect than Syringopicroside and hydroxytyrosol (SH) and NPP alone. The targeting ability of GA enabled HT and SYR in GPP to reach the liver accurately, and played a synergistic role to maximize their therapeutic effects. This study provides a novel strategy against hepatitis B virus, and also provides a feasible scheme for improving the low bioavailability of the active components of traditional Chinese medicine.

Ferroelectricity, one of the keys to realize nonvolatile memories owing to the remanent electric polarization, has been an emerging phenomenon in the two-dimensional (2D) limit. Yet the demonstrations of van der Waals (vdW) memories using 2D ferroelectric materials as an ingredient are very limited. Especially, gate-tunable ferroelectric vdW memristive device, which holds promises in future multi-bit data storage applications, remains challenging. Here, we show a gate-programmable multi-state memory by vertically assembling graphite, CuInP2S6, and MoS2layers into a metal(M)-ferroelectric(FE)- semiconductor(S) architecture. The resulted devices seamlessly integrate the functionality of both FE-memristor (with ON-OFF ratios exceeding 105and long-term retention) and metal-oxide-semiconductor field effect transistor (MOS-FET). It thus yields a prototype of gate tunable giant electroresistance with multi-levelled ON-states in the FE-memristor in the vertical vdW assembly. First-principles calculations further reveal that such behaviors originate from the specific band alignment between the FE-S interface. Ourfindings pave the way for the engineering of ferroelectricity-mediated memories in future implementations of 2D nanoelectronics.

Grain boundaries (GBs) relaxation is a promising and effective strategy to improving GB stability or stabilizing nanocrystalline metals. However, previous studies mainly focused on nanocrystalline pure metals and GB behaviors therein, without considering the role of foreign atoms such as impurity or alloying atoms in GB relaxation. In this work, the shear-strain induced structural relaxation of pure Cu Σ3 [110](112) symmetric tilt GBs (STGBs), and the effects of foreign elements (Fe and Ni) and temperature on the GB relaxation were investigated in detail by molecular dynamics method. The results show that shear strain can trigger the structural relaxation of pure, Fe- and Ni-containing Cu GBs by the emission of Shockley partial dislocations from Cu GBs. Both Fe and Ni have impediment effects on the shear-strain induced GB relaxation, though the content of Fe or Ni atom (0.00165 at.%) is quite low in the GB model. The temperature cannot trigger GB relaxation independently within the considered temperature range, but play a positive role in the shear-strain induced structural relaxations of pure, Fe- and Ni-containing Cu Σ3 [110](112) STGBs. Our work might gain new insights into the mechanically induced GB relaxation in nanocrystalline copper and could be beneficial for improving the stability of Cu GBs.

Ternary composite ZnO/ZnS/ZnSe nanosheets (NSs) with diverse proportions of three modules successfully manufactured by a plain two-step solvothermal way with the comparison to ZnO/ZnS and ZnO/ZnSe NSs. ZnO/ZnS/ZnSe NSs have the alike geometrical morphology with the ZnO/ZnS and ZnO/ZnSe NSs. The UV–Vis diffuse reflectance spectra (DRS) result reveals that ternary composites can assimilate more quantum photons which are helpful to the photocatalytic reaction. The photocurrent density of ternary composite structures is higher in the photocurrent response of all samples under simulated solar light illumination. Compared with ZnO/ZnS or ZnO/ZnSe binary composite NSs, ZnO/ZnS/ZnSe ternary composite NSs prove a prominent photodegradation property for degradation of rhodamine B (RhB) aqueous solution under simulated sunlight illumination. The project mechanism was confirmed by radical trapping experiments and a superoxide radical anion formation assay. ZnO/ZnS/ZnSe NSs with a molar ratio of S/Se (0.97) display the most outstanding photocatalytic activity and well photocatalytic stability.

BACKGROUND Norcantharidin (NCTD) is suitable for the treatment of primary liver cancer, especially early and middle primary liver cancer. This compound can reduce tumors and improve immune function. However, the side effects of NCTD have limited its application. There is a marked need to reduce the side effects and increase the efficacy of NCTD. AIM To develop a nanomaterial carrier, NCTD-loaded metal-organic framework IRMOF-3 coated with a temperature-sensitive gel (NCTD-IRMOF-3-Gel), aiming to improve the anticancer activity of NCTD and reduce the drug dose. METHODS NCTD-IRMOF-3-Gel was obtained by a coordination reaction. The apparent characteristics and in vitro release of NCTD-IRMOF-3-Gel were investigated. Cell cytotoxicity assays, flow cytometry, and apoptosis experiments in mouse hepatoma (Hepa1-6) cells were used to determine the anti-liver cancer activity of NCTD-IRMOF-3-Gel in in vitro models. RESULTS The particle size of NCTD-IRMOF-3-Gel was 50-100 nm, and the particle size distribution was uniform. The release curve showed that NCTD-IRMOF-3-Gel had an obvious sustained-release effect. The cytotoxicity assays showed that the free drug NCTD and NCTD-IRMOF-3-Gel treatments markedly inhibited Hepa1-6 cell proliferation, and the inhibition rate increased with increasing drug concentration. By flow cytometry, NCTD-IRMOF-3-Gel was observed to block the Hepa1-6 cell cycle in the S and G2/M phases, and the thermosensitive gel nanoparticles may inhibit cell proliferation by inducing cell cycle arrest. Apoptosis experiments showed that NCTD-IRMOF-3-Gel induced the apoptosis of Hepa1-6 cells. CONCLUSION Our results indicated that the NCTD-IRMOF-3-Gel may be beneficial for liver cancer disease treatment.

Membrane module integrity monitoring is essential in the water treatment process. Problems such as high cost and low sensitivity limit the development of existing detection methods. An intelligent detection method for membrane integrity based on array impedance measurement is proposed in this paper. The boundary voltage data are collected in real time through the designed electrical sensor array. A deep learning algorithm is used to analyze the degree of damage of the membrane based on the collected voltage data. Membrane integrity testing experiments are conducted for different water qualities (lake water and domestic sewage) under different aeration intensities and membrane fluxes. Detection models based on a convolutional neural network (CNN) and deep neural network (DNN) are built, and the identification results are compared with those of the average voltage method. The experiments show the following: 1) For the tests based on random samples of membranes under detection, the overall sensitivities of the CNN in the lake water experiment and domestic sewage experiment reach 97.3% and 98.5%, respectively, which are significantly higher than those of the DNN method (94.1% and 93.6%) and the average voltage method (87.4% and 77.4%). 2) When the membrane process is affected by the variation in the aeration intensity and membrane flux, the CNN still has the best robustness. Hence, the new method could stably and accurately reflect the level of membrane breakage, even mild damage to the membrane, under flow disturbance.

Many factors have been confirmed to affect ferroelectric phase formation in HfO2-based thin films but there was still a lack of general view on describing them. This paper discusses the intrinsic parameters to stabilize the ferroelectric phase of HfO2 thin films to approach this general view by investigating the separate effects of dopant, oxygen vacancy (VO), and specific surface area on the crystal phase of the films. It is found that in addition to extensively studied dopants, the ferroelectric orthorhombic phase can also be formed in pure HfO2 films by only introducing sufficient VO independently, and it is also formable by only increasing the specific surface area. By analyzing the common physics behind these factors, it is found that orthorhombic phase formation is universally related to strain in all the above cases with a given temperature. To get a general view, a physical model is established to describe how the strain influences ferroelectric phase formation during the fabrication of HfO2-based films based on thermodynamic and kinetics analysis.

ConspectusRefining grains of metals and alloys is an effective approach to tailor their properties and performance. Plastic deformation is routinely used for structure refinement, with which micros...

Motion tracking is an effective approach for the management of respiratory motion during the medical imaging process, which has always been a major concern in diagnostic imaging, interventional, and noninvasive therapy. However, the low imaging speed of traditional medical imaging techniques limits the practical application of real-time motion tracking. Electrical impedance tomography (EIT) is proved to be an effective tool for continuous monitoring of lung activity/status. However, the respiratory motion has never been studied in the medical EIT field before. In this article, preliminary research of lung movement during the respiratory process is first studied based on EIT. Multiring electrode thorax models under different respiratory statuses were constructed to obtain simulation data of EIT. A modified TV algorithm is used for the estimation of lung volume and movement based on 3-D EIT images, which improve the quality of reconstruction by approximately 30% and 20% compared with the traditional Tikhonov method and the total variation (TV) method, respectively. Both simulations and experiments were conducted to show the potential of respiratory motion tracking through 3-D EIT reconstruction.

Through the construction of a PEDOT:PSS/α-Ga2O3 heterojuntion on FTO by hydrothermal, low-temperature annealing and spin-coating processes, a self-powered PEDOT:PSS/α-Ga2O3 nanorod array/FTO photodetector has successfully realized dual-band photodetection; it possesses a solar-blind UV main band with a peak responsivity of ∼1.43 mA W−1 at 245 nm and a visible subband with a peak responsivity of ∼0.07 mA W−1 at 540 nm. Due to the highly efficient PEDOT:PSS/α-Ga2O3 heterojuntion, the peak responsivity in the solar-blind UV range is not only ∼104 times as high as that of the compared α-Ga2O3/FTO photodetector, but also one of the best values among the popular self-powered α-Ga2O3 nanorod array photodetectors based on the liquid-state photoelectrochemical structure, thus indicating the realization of a high-responsivity solid-state device with more convenient operation. More importantly, our photodetector has realized solar-blind UV/visible dual-band photodetection for the first time among self-powered Ga2O3-based dual-band photodetectors, which paves a feasible way to demonstrate high-performance solid-state α-Ga2O3 solar-blind UV/visible dual-band photodetection by easy, common and low-cost processes.

In this article, the temperature behavior of a silicon ring resonator is experimentally investigated for cryogenics. The ring resonator shows a linear sensitivity of 63.9 pm/K in the temperature range from 180 K to 300 K. And the experimental results agree well with the simulated data. The response time of the sensor is investigated by thermal analysis and a fast response of 325 ms is experimentally achieved. In addition, the developed sensor shows high performance in repeatability and stability. Based on our work, for the first time, silicon based ring resonators are applied to cryogenic temperature sensing with the prominent advantages of compactness, chip-scale integration and complementary metal oxide semiconductor (CMOS) compatibility. This work proves that silicon ring resonators are a potential platform for cryogenic monitoring.

Lithium-sulfur battery (Li–S) is considered as one of the new-generation rechargeable batteries with high performance because of its extremely high theoretical capacity, energy density, environmental harmony and low cost. However, low electrical and ionic conductivity of sulfur, safety concerns and parasitic reaction generated by the dissolved polysulfide species in electrolyte hinder the commercialization of Li–S battery. Herein, we report a polyhedral porous structure comprising of carbon coating metal selenide nanoparticles (CoSe2/C), which could not only host sulfur for Li-S battery owing to its porous and conductive structure, but also mitigate the shuttle phenomenon by polysulfides adsorption and catalytic acceleration of redox kinetics. As a result, a performance enhanced CoSe2/C-S electrode for Li-S battery is achieved.

Macrophages (Mø) are immune cells with natural phagocytic ability and play an important role in tumorigenesis, development and metastasis. Mø play a dual role of tumour inhibition and tumour promotion in tumour development due to their two different phenotypes. Mø in the tumour microenvironment have long been referred to as tumour-associated Mø (TAMs). Mø are mainly involved in tumour resistance, cancer metastasis and mediating immunosuppression. Nowadays, Mø and Mø membranes have been widely used in drug delivery systems (DDSs) because of their good biocompatibility, natural phagocytosis and their important role in tumour development. In this review, from the perspective of Mø's role in tumour development, we present strategies and drugs of Mø targeting and focusing on the several types of biomimetic nanoparticles constructed by Mø and Mø membranes in tumour therapy, and discuss the problem of this delivery system in present research and future directions.

Negative capacitance (NC) effects in ferroelectric/paraelectric (FE/PE) stacks have been recently discussed intensively in terms of the steep subthreshold swing (SS) in field-effect transistors (FETs). It is, however, still disputable to stabilize quasi-static-NC effects. In this work, stepwise internal potential jumps in a metal/FE/metal/PE/metal system observed near the coercive voltage of the FE layer are reported through carefully designed DC measurements. The relationship of the internal potential jumps with the steep SS in FETs is also experimentally confirmed by connecting a FE capacitor to a simple metal-oxide-semiconductor FET. On the basis of the experimental results, the observed internal potential jumps are analytically modelled from the viewpoint of bound charge emission associated with each domain flip in a multiple-domain FE layer in a FE/PE stack. This view is different from the original NC concept and should be employed for characterizing FE/PE gate stack FETs., Negative capacitance (NC) effects that could allow steep subthreshold swing (SS) in field-effect transistors (FETs) are still controversially discussed. Here the authors propose a model distinct from the NC concept, taking into account domain flips in multiple-domain ferroelectric/paraelectric gate stack FETs.