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In this study, a new type of ceramic composite (PZSC/ZnO) was successfully synthesized using N, P, and S co‐doped carbon microspheres derived from polyphosphazene with zinc oxide. The morphology and structure were characterized by Fourier transform infrared spectroscopy, X‐ray photoelectron spectroscopy, scanning electron microscopy, energy‐dispersive spectroscopy, Raman, X‐ray diffraction, BET, and thermogravimetric. Batch experiments were used to explore the adsorption performance under different pH values, initial concentrations, contact times, and temperatures. The results showed that the maximum adsorption capacity of the PZSC/ZnO ceramic composite for uranium was 470.5 mg/g (pH = 5.5, t = 40 min, and T = 25°C). The adsorption process followed the nonlinear Langmuir model and the pseudo‐second‐order kinetic model, demonstrating that the monolayered combination of U(VI) with the PZSC/ZnO ceramic composite and the adsorption mechanism was chemical adsorption. Thermodynamic data revealed that the adsorption was a spontaneous endothermic process. Furthermore, P and N may be involved in the adsorption of uranyl ions through binding to the O atoms from ZnO. The main forces between U(VI) and the PZSC/ZnO ceramic composite were attributed to ZnO and heteroatoms doped in the material. [ABSTRACT FROM AUTHOR]

Elevated atmospheric nitrogen (N) deposition has caused many adverse effects on ecosystem services. However, the impacts of N deposition and its interaction with soil moisture on soil seed bank remain largely unknown in semiarid grasslands. Here, we quantified the effects of two soil water regimes (HW: watered to field capacity every day; LW: watered to field capacity every 2 days) and two types of N addition (NO3−‐N and NH4+‐N) with different levels on seed bank germination in two separate trials in April and July 2015 in a semiarid grassland on the Loess Plateau, China. Results showed seed bank germination was remarkably inhibited under the LW soil water regime. Species composition of emerged seedlings significantly differed between the two soil water regimes. N addition promoted seed bank germination under the HW soil water regime. This promoting effect was less noticeable under the LW, while still significant in the high level of NH4+‐N in the July trial. N addition did not alter the species composition of emerged seedlings. Overall, this study suggests that soil moisture controls soil seed bank germination and species composition of emerged seedlings. Soil N addition, for example, by N deposition, greatly promotes soil seed bank germination when soil moisture is high (e.g., during seed germination season in July), and still marginally facilitates seed germination under low soil moisture conditions (e.g., at the beginning of the growing season in April). N deposition may therefore deplete the grassland soil seed bank if other processes (e.g., seed input) remain unchanged. [ABSTRACT FROM AUTHOR]

Novel terpolymers were developed with ester group incorporation (BDT-2EST). DM1 with 5% BDT-2EST possesses suitable crystallinity and miscibility matching with Y6 acceptor to offer an excellent power conversation efficiency up to 17.21%. Moreover, the intertwined random features in DM1 offer robust photovoltaic performances with a broad molecular weight tolerance. [ABSTRACT FROM AUTHOR]

HfO2‐based ferroelectric memory is one of the most attractive candidates for embedded memory in future monolithic‐M3D integrated‐circuit (IC). However, ferroelectricity and endurance will degrade at lower annealing temperatures due to the limitation of the M3D‐IC in thermal budget, which significantly inhibits its potential for many applications. In this work, a novel process technology using As5+ implantation (As‐imp) at the bottom electrode (BE) in TiN/Hf0.5Zr0.5O2(HZO)/TiN capacitors is proposed. The HZO film shows excellent ferroelectricity and improves endurance at the annealing temperatures of 350 and 400 °C, especially when the dose of As‐imp is 1 × 1016, where the endurance of the HZO film is up to 1.5 × 1011, and the remnant polarization (Pr) far exceeds the reference capacitor without BE As‐imp, where 2Pr is greater than 40 °C cm−2 after 1.5 × 1011 cycles. The underlying physical mechanism is that the oxidation reaction of introduced As5+ during the film deposition releases extra oxygen atoms to fill the oxygen vacancies (Vo) near the BE interface due to the occurrence of the thermal reduction reaction in the subsequent annealing process. This study paves the way for the integration of HZO‐based ferroelectric embedded memory in future high‐performance and energy‐efficient 3D‐ICs. [ABSTRACT FROM AUTHOR]

A label-free immunosensor was constructed in oxidation and reduction dual channel mode for the trace detection of cancer antigen 125 (CA125) in serum. The gold–vertical graphene/titanium dioxide (Au–VG/TiO2) electrode was used as the signal-amplification platform, and cytosine and dopamine were used as probes in the oxidation and reduction channels, respectively. VG nanosheets were synthesized on a TiO2 nanotube array via chemical vapor deposition (CVD), and Au nanoparticles were deeply embedded on the surface and in the root of the VG nanosheets via electrodeposition. The CA125 antibody was then directly immobilized onto the electrode surface, benefitting from its natural affinity for Au nanoparticles. In the oxidation and reduction channels the CA125 antibody–Au–VG/TiO2 immune electrode had the same response concentration range (0.01–1000 mU∙mL−1) for the determination of the CA125 antigen. However, the oxidation channel had a higher sensitivity (14.82 μA•(log(mU•mL−1))−1 at a working potential of ~ 1.25 V vs. SCE), lower detection limit (0.0001 mU∙mL−1), higher stability, and lower performance deviation than the reduction channel. This immunosensor was successfully used for CA125 detection in human serum. The recoveries of spiked serum samples ranged from 99.8 ± 0.5 to 100 ± 0.4%. The study on the difference in the sensing performance between oxidation and reduction channels provides a preliminary experimental reference for exploring dual-channel synchronous detection immunosensors and verifying the accuracy of the assay based on dual-channel data, which will promote the development of reliable electrochemical immunosensor technology. [ABSTRACT FROM AUTHOR]

As an interconnect metal, cobalt (Co) has been employed in state-of-the-art CMOS technology to substitute conventional Copper (Cu) or Tungsten (W) due to its surplus advantages. A single layer of Co–Ti alloy would replace the relatively thick Ta/TaN or Ti/TiN bilayer as both barrier and liner layer to match the Co interconnects, which strengthens the advantages for Co interconnects. In this article, the reliability of Co0.65Ti0.35 as both barrier and liner layer in Co interconnects is further evaluated through time-dependent dielectric breakdown experiment which is critical for its practical application in devices. It is found that the Co0.65Ti0.35 indeed can act as a single barrier/liner layer in a long-term operation. Co0.65Ti0.35 effectively prevents the diffusion of a part of Co ions, delays the formation of conducting path, and allows the SiO2 dielectric layer to withstand tremendous voltage stress. What's more, the characteristic lifetime of devices with Co0.65Ti0.35 predicted by the √E model is significantly prolonged from 116 days to 32 years, greatly satisfying the reliability requirements of the barrier layer. [ABSTRACT FROM AUTHOR]

Serious agglomeration of ultrathin TiSix employed in source–drain (S–D) ohmic contacts after high-temperature annealing was manifested in previous work. This severely restricts its application in state-of-the-art DRAM peripheral 3-D FinFET transistors. In this work, the effects of hafnium (Hf) interlayer on the thermal stability of ultrathin TiSix in TiSix/n+-Si ohmic contacts were systematically studied. As-prepared ultrathin TiSix and TiSix/n+-Si ohmic contacts with 0-, 1-, 2-, and 3-nm Hf interlayers were characterized by means of specific contact resistivity ($\rho _{\text {c}}$), transmission electron microscopy (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). It is found that compared to the counterparts with 0-, 2-, and 3-nm Hf, the presence of 1-nm Hf interlayer is proven to be effective in enhancing the thermal stability of ultrathin TiSix significantly. With 1-nm Hf, amorphous HfO2, and Hf silicate are readily formed, which hinders the interdiffusion between Ti and Si atoms and resultant agglomeration of ultrathin TiSix films. This is thought to be responsible for such a remarkably enhanced thermal stability of ultrathin TiSix in TiSix/n+-Si ohmic contacts. [ABSTRACT FROM AUTHOR]

This paper presents an improved trajectory tracking controller based backstepping control algorithm to address the trajectory tracking problem of an underactuated Unmanned Surface Vessel (USV). A Three Degree of Freedom (DOF) underactuated maneuvering motion model for water-jet-propelled USV is established, and controller can track both straight line trajectory and curve trajectory with relatively high accuracy. The stability of USV system is proved by BIBO (bounded-input-bounded-output stable) characteristics, then simulation experiments are carried out to demonstrate the robustness and precise control performance of the controller.