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TC4 alloy is widely used in dental implantation due to its excellent biocompatibility and low density. However, it is necessary to further improve the corrosion resistance and surface hardness of the titanium alloy to prevent surface damage that could result in the release of metal ions into the oral cavity, potentially affecting oral health. In this study, Ti-N-O layers were fabricated on the surface of TC4 alloy using a two-step hollow cathode plasma source oxynitriding technique. This resulted in the formation of TiN, Ti2N, TiO2, and nitrogen-stabilized α(N)-Ti phases on the TC4 alloy, forming a Ti-N-O modified layer. The microhardness of the samples treated with plasma oxynitriding (PNO) was found to be 300–400% higher than that of untreated (UN) samples. The experimental conditions were set at 520 °C, and the corrosion current density of the PNO sample was measured to be 7.65 × 10−8 A/cm2, which is two orders of magnitude lower than that of the UN sample. This indicates that the PNO-treated TC4 alloy exhibited significantly improved corrosion resistance in the artificial saliva solutions.

In this study, an optimized XOR logic gate is briefly proposed based on memristors. The proposed XOR exhibits a simple structure that comprises two memristors; it requires merely two steps to complete logic. The inputs of the gate are applied by voltage and memristive resistance, and the output is stored as the resistance value of the output cell. Furthermore, the encryption and decryption based on such a circuit have been verified by performing a parallel electrical test successfully. At the same time, the parallel scheme and the cascaded serial scheme are compared in detail. Moreover, the mentioned energy-efficient circuit helps achieve more complex logic functions. Abiding by Kirchhoff’s law, the effect of the memory window and the variation of devices’ parameter on the calculation accuracy has been further analyzed in depth, which helps develop a complete binary logic calculation theory. On that basis, a digital in-memory calculation system can be more effectively built based on memristors.

The Ni/AlN composite coating was prepared for increasing corrosion and elements interdiffusion resistance of GH3535 alloy in molten fluoride salts, and the effect of mechanical interlocking on adhesion strength between AlN layer and nickel coating was also studied. Results indicated that the adhesion strength between AlN layer and nickel coating could be significantly enhanced through mechanical interlocking effect, which effectively prevented the nickel coating from flaking off at elevated temperature. Through an etching pre-treatment of AlN layer, the corrosion resistance of the Ni/AlN coated GH3535 alloy in molten FLiNaK salt was further improved, and elements interdiffusion between the substrate and nickel coating was completely suppressed. AlN layer as a diffusion barrier remained compact and continuous in Ni/GH3535 system after high-temperature molten salt corrosion. Moreover, a Ni–P layer consisting of Ni3P and Ni phases formed in the Ni coating after corrosion.

This paper discusses a mechanism and method for polarization enhancement in fabricated Hf0.5Zr0.5O2 (HZO) capacitors. The proposed reawakening voltage operation method (RVOM) to HZO films at elevated temperatures increases the transient switching current and polarization. The change in conduction mechanisms for the HZO capacitor current after RVOM can be observed by fitting leakage current curves. The generation of oxygen vacancies (VO) by RVOM causes a rapid increase in the leakage current and a gradual degradation in the breakdown voltages of HZO capacitors. As a result, while an appropriate amount of VO generation improves the polarization, an excess will damage the reliability of HZO films. Furthermore, the augmentation of polarization does not disappear after the cooling process, which indicates that the VO as induced by RVOM does not attenuate as the temperature decreases. Our approach and the experimental results have generated ideas on how to improve the polarization of HZO films.

The adjustable conductance of a two-terminal memristor in a crossbar array can facilitate vector-matrix multiplication in one step, making the memristor a promising synapse for efficiently implementing neuromorphic computing. To achieve controllable and gradual switching of multi-level conductance, important for neuromorphic computing, a theoretical design of a superlattice-like (SLL) structure switching layer for the multi-level memristor is proposed and validated, refining the growth of conductive filaments (CFs) and preventing CFs from the abrupt formation and rupture. Ti/(HfO

There arises the growing interest of negative capacitance field effect transistors (NCFETs) for low-power applications, however, temperature as an inevitable influencing factor, its effects on NCFETs require more research for practical applications. In this work, we fabricated Hf0.5Zr{0.5}O{2}(HZO) based NC p-channel FETs and developed a corresponding TCAD simulation deck to study the temperature impact. DC characteristics of NCFETs and its baseline MOSFETs at the common operation temperature range (−50 to 85°C) are measured and simulated. With the increase of temperature, NCFET subthreshold slope (SS) increases much faster than kT / ${q}$ demonstrating pyroelectric effect, and exceeds kT / ${q}$ at ~350K and baseline MOSFETs at ~360K. Similarly, its on-current decreases more rapidly than baseline devices. Finally, we explained the temperature characteristics of NCFET with the help of a developed model through Landau-Khalatnikov (L-K) theory and temperature dependent internal gain ( $\text{A}_{V}$ ).

A TiN interlayer with high electrical conductivity was prepared between the GH3535 alloy and the Ni coating as a diffusion barrier to elements interdiffusion with the goal of increasing the corrosion resistance of GH3535 alloy in molten FLiNaK salt at 700 ℃. Results indicated that Ni coating could be directly electroplated on the TiN coated GH3535 alloy without extra conductive transition layer. TiN layer showed excellent thermal and chemical stabilities at elevated temperature in this molten salt system, without phase decomposition. The Ni/TiN composite coating was stable enough to resist corrosion in LiF-NaF-KF molten salt at 700 ℃. Elements interdiffusion between the substrate and Ni coating could be effectively inhibited and the corrosion resistance of the alloy was greatly enhanced. Besides, the TiN interlayer remained continuous and well adhered to the Ni coating as well as the substrate after corrosion test.

We have successfully fabricated Pt/BiFeO 3 / SrRuO 3 /SrTiO 3 resistive devices with magnetron sputtering at different deposition temperatures and thicknesses. The resistive behaviors and conduction mechanisms can be modulated by the thickness and deposition temperatures of BFO films. BFO films with smaller thickness and higher deposition temperature show larger memory window and lower switching voltage possibly due to the more oxygen vacancies and defects.

Two-dimensional (2D) materials are promising for next-generation photo detection because of their exceptional properties such as a strong interaction with light, electronic and optical properties that depend on the number of layers, and the ability to form hybrid structures. However, the intrinsic detection ability of 2D material-based photodetectors is low due to their atomic thickness. Photogating is widely used to improve the responsivity of devices, which usually generates large noise current, resulting in limited detectivity. Here, we report a molybdenum-based phototransistor with MoS2 channel and α-MoO3-x contact electrodes. The device works in a photo-induced barrier-lowering (PIBL) mechanism and its double heterojunctions between the channel and the electrodes can provide positive feedback to each other. As a result, a detectivity of 9.8 × 1016 cm Hz1/2 W−1 has been achieved. The proposed double heterojunction PIBL mechanism adds to the techniques available for the fabrication of 2D material-based phototransistors with an ultrahigh photosensitivity., Here, the authors exploit a photo-induced barrier-lowering mechanism in MoS2/ α-MoO3-x heterojunctions to realize two-dimensional phototransistors with enhanced performance and fast response at low bias voltage.

We demonstrate for the first time ZrO2 ferroelectric field-effect transistors (FeFETs) for embedded non-volatile memory applications. Multiple sweeps of polarization versus voltage measurement demonstrate that a metal/ZrO2/Ge capacitor is entirely free of wake-up effect and has significantly improved fatigue characteristics compared to a HfZrOx control device. Thanks to relatively small remnant polarization and a high-quality ZrO2/Ge interface, up to 107 cycles program/erase endurance, 10 ns program/erase speed, and >10-year data retention at 85 °C are achieved.

CrN barrier was deposited between a Ni-electroplating and GH3535 alloy with the goal of prohibiting elements interdiffusion and increasing corrosion resistance in molten FLiNaK (LiF-NaF-KF: 46.5-11.5-42.0 mol%) salt. Results indicate that the Ni-coating apparently improves corrosion resistance of GH3535 in molten fluoride salts, but Cr and Fe diffuse constantly from the alloy to the Ni-coating. They are finally dissolved into the molten salt, causing corrosion of the GH3535 alloy. With a CrN diffusion barrier, however, elements interdiffusion has been completely suppressed and the corrosion resistance is further improved by more than eight times comparing to the CrN-free Ni-coated alloy.

A series of novel ligustrazine-chalcone hybrids were synthesized and evaluated for their in vitro and in vivo antitumor activities. The results showed that most of these compounds exhibited significant in vitro cytotoxicity against MDA-MB-231, MCF-7, A549 and HepG2 cell lines with IC50 values as low as sub-micromole. Among them, compounds 6c and 6f possessed better comprehensive characteristics for the antiproliferation effects on both MDA-MB-231 (IC50: 6c, 1.60 ± 0.21 μM; 6f, 1.67 ± 1.25 μM) and MCF-7 (IC50: 6c, 1.41 ± 0.23 μM; 6f, 1.54 ± 0.30 μM). They also exhibited the potent colony-formation inhibitory abilities on above two cell lines in both concentration and time dependent manners, as well as the significantly suppression capabilities against the migration of such cell lines in a concentration dependent manner by wound-healing assay. Of note, compound 6c could significantly induce the apoptosis of MDA-MB-231 cells in a concentration dependent manner and inhibited the transformation of the growth cycle of MDA-MB-231 cells and blocked the cell growth cycle in G0/G1 phase. Moreover, the in vivo antiproliferation assay of compound 6c on TNBC model indicated such compound had a remarkable potency against tumor growth with a widely safety window. Further immunohistochemistry analysis illustrated that compound 6c was provided with a potent capacity to significantly reduce the Ki-67 positive rate in a dose dependent manner. All the results suggested that these hybrids presented both in vitro and in vivo proliferation inhibition potency against breast cancer and further development with good therapeutic potential should be of great interest.

In this paper, the cause of inverse drain induced barrier lowering effect in negative capacitance field effect transistors (NCFETs) is discussed, and a capacitance model is given. Based on inverse DIBL effect, negative differential resistance phenomenon could occur, and these two effects are hard to be removed. Since higher on-off ratio and lower NDR cannot be achieved at the same condition, their relationship with device structure is also studied.

The volumetric swelling and hardening effect of irradiated Hastelloy N alloy were investigated in this paper. 7 MeV and 1 MeV Xe ions irradiations were performed at room temperature (RT) with irradiation dose ranging from 0.5 to 27 dpa. The volumetric swelling increases with increasing irradiation dose, and reaches up to 3.2% at 27 dpa. And the irradiation induced lattice expansion is also observed. The irradiation induced hardening initiates at low ion dose (≤1dpa) then saturates with higher ion dose. The irradiation induced volumetric swelling may be ascribed to excess atomic volume of defects. The irradiation induced hardening may be explained by the pinning effect where the defects can act as obstacles for the free movement of dislocation lines. And the evolution of the defects' size and number density could be responsible for the saturation of hardness.

In this Letter, a Ti/HfOx/Pt memristor with a modified Ti electrode created by inserting polydopamine (PDA)/Ag nanoparticles (AgNPs) between the Ti electrode and functional layer is reported. This memristor exhibits a significant improvement in the uniformity of device parameters [including set voltage, reset voltage, high resistance state (HRS) resistances, low resistance state (LRS) resistances, endurance, and retention] compared to conventional memristors. The AgNPs embedded in PDA renders a reduced variability in HRS and LRS resistances from 47% to 7%, and 46% to 11%, respectively. By fitting Poole–Frenkel and Ohmic behavior models, the consistency of the conductive mechanism of the devices before and after modification has been proven, which is further enhanced through variable temperature tests and the simulation of electric field distribution. It is believed that AgNPs play a lightning rod role in guiding the growth of conductive paths; thus, by growing AgNPs in situ on PDA film on the Ti electrode, it reduces the parameter variability.

Background Inflammation and endothelial dysfunction is implicated in the atherosclerosis initiation and progression in the setting of hyperlipidemia. Colchicine is a potent anti-inflammatory agent and whether colchicine combined with atorvastatin has synergistic effects on inflammation amelioration and endothelial function improvement is unknown. Methods Hyperlipidemic rat model was produced by high-fat and high-cholesterol diet for 6 weeks. Rats with normal diet were served as shame group. In hyperlipidemic group, normal saline, atorvastatin (10 mg/kg body weight/day), colchicines (0.5 mg/kg body weight/day), or atorvastatin combined with colchicines (same dosages) were prescribed for 2 weeks. Serum levels of lipid profile, C-reactive protein (CRP), liver enzyme, lipoprotein associated phospholipase A2 (Lp-PLA2) and nitric oxide (NO) production were serially assessed. Results Before the beginning of the study, all laboratory variables were comparable among each group. After 6 weeks of hyperlipidemic model production, serum levels of cholesterols, CRP and Lp-PLA2 were significantly increased when compared to sham group, whereas NO production was reduced. With 2 weeks of colchicine therapy, serum levels of CRP and Lp-PLA2 were decreased and NO production was enhanced in the colchicine group in a lipid-lowering independent manner. Added colchicine into atorvastatin therapy further improved NO production and decreased CRP and Lp-PLA2 levels, indicating a potential synergism of colchicine and atorvastatin. Conclusion Colchicine combined with atorvastatin may have stronger protective effects on improving endothelial function and ameliorating inflammation in rats with hyperlipidemia.