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In this letter, we report analog switching characteristics in an analog resistive random access memory device based on a TiW/Al2O3/Ta2O5/Ta stack. For this device, both oxides were grown by using an atomic layer deposition system and the oxygen vacancies were found to exist at the interface of these oxides by using angle-resolved X-ray Photoelectron Spectroscopy. The device exhibits analog switching behaviors. Multiple states were achieved by applying 128 consecutive identical pulses of <20 μs duration and stable for at least 104 s. These characteristics show that the TiW/Al2O3/Ta2O5/Ta device is a promising candidate for synaptic applications. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A porous K-CMSP was prepared with mussel shell powder and activated by K 2 CO 3. • K-CMSP modified with L-ARG had rendered a positively charged surface. • Immobilized microalgae could survive for more than 60 days. • Immobilized microalgae could revive to normal growth level within 10 days. • The removal rate of N and P by immobilized microalgae were 95.0% and 88.63%. Abstract In this work, calcined mussel shell powder (CMSP) was activated by K 2 CO 3 (K-CMSP), and this porous K-CMSP surface was modified by L-arginine (L-ARG) to render porous biomass a positively charged surface, which was innovatively utilized as a carrier to immobilize microalgae by adsorption via electrostatic interactions. The pore and the surface structures of CMSP and K-CMSP were characterized by XRD, FTIR, BET and SEM. The surface morphology of immobilized microalgae was visualized via using inverted optical microscope and SEM. It was found that microalgae could survive for 60 days, and the loss rate of chlorophyll-a preserved at −24 °C was the lowest, 44.73%. The microalgae could revive to normal growth level within 10 days and the cell content of microalgae was the highest at 25 °C, 2.8022 × 106 cell/mL. At 25 °C, the highest removal rate of N and P was obtained about 95.0% and 88.63%, respectively. [ABSTRACT FROM AUTHOR]

Abstract: Evaluation of radiation dose is very important for the detection of radiation damage. γ-H2AX is a popular biological dosimeter to evaluate the radiation effect. Typically, bulky and expensive commercial flow cytometers are used to detect γ-H2AX. This paper presents a miniaturized and high sensitive cytometer using a microfluidic chip for evaluating the radiation dose by detecting the mean immunofluorescence intensity of γ-H2AX. A compact optical focusing system and a shift-phase differential amplifier are designed to improve the detection sensitivity. Sample lymphocyte cells are stained by FITC fluorescent dye after being irradiated by UVC. Comparison experiments between the developed miniature cytometer and a commercial flow cytometer were conducted under different radiation doses. The developed microfluidic cytometer also demonstrates a good linear correlation between the measured fluorescence intensity and the irradiation dose with a detection limit similar to that of the commercial flow cytometer. The developed cytometer can evaluate quantitatively the radiation dose by the mean fluorescence intensity of γ-H2AX with a significantly smaller amount of blood samples than a commercial flow cytometer. [Copyright &y& Elsevier]

In this work, 10 nm scandium-doped aluminum nitride (AlScN) capacitors are demonstrated for the construction of the selector-free memory array application. The 10 nm Al0.7Sc0.3N film deposited on an 8-inch silicon wafer with sputtering technology exhibits a large remnant polarization exceeding 100 µC/cm2 and a tight distribution of the coercive field, which is characterized by the positive-up-negative-down (PUND) method. As a result, the devices with lateral dimension of only 1.5 μm show a large memory window of over 250% and a low power consumption of ~40 pJ while maintaining a low disturbance rate of <2%. Additionally, the devices demonstrate stable multistate memory characteristics with a dedicated operation scheme. The back-end-of-line (BEOL)-compatible fabrication process, along with all these device performances, shows the potential of AlScN-based capacitors for the implementation of the high-density selector-free memory array. [ABSTRACT FROM AUTHOR]

Ferroelectric scandium-doped aluminum nitride (Al1-xScxN) is of considerable research interest because of its superior ferroelectricity. Studies indicate that Al1-xScxN may suffer from a high leakage current, which can hinder further thickness scaling and long-term reliability. In this work, we systematically investigate the origin of the leakage current in Al0.7Sc0.3N films via experiments and theoretical calculations. The results reveal that the leakage may originate from the nitrogen vacancies with positively charged states and fits well with the trap-assisted Poole-Frenkel (P-F) emission. Moreover, we examine the cycling behavior of ferroelectric Al0.7Sc0.3N-based FeRAM devices. We observe that the leakage current substantially increases when the device undergoes bipolar cycling with a pulse amplitude larger than the coercive electric field. Our analysis shows that the increased leakage current in bipolar cycling is caused by the monotonously reduced trap energy level by monitoring the direct current (DC) leakage under different temperatures and the P-F emission fitting. [ABSTRACT FROM AUTHOR]

Strain engineering is an effective way to modify functional properties of thin films. Recently, the importance of octahedral rotations in pervoskite films has been recognized in discovering and designing new functional phases. Octahedral behavior of SrRuO3 film as a popular electrode in heterostructured devices is of particular interest for its probable interfacial coupling of octahedra with the functional overlayers. Here we report the strain engineering of octahedral rotations and physical properties that has been achieved in SrRuO3 films in response to the substrate-induced misfit strains of almost the same amplitude but of opposite signs. It shows that the compressively strained film on NdGaO3 substrate displays a rotation pattern of a tetragonal phase whilst the tensilely strained film on KTaO3 substrate has the rotation pattern of the bulk orthorhombic SrRuO3 phase. In addition, the compressively strained film displays a perpendicular magnetic anisotropy while the tensilely strained film has the magnetic easy axis lying in the film plane. The results show the prospect of strain engineered octahedral architecture in producing desired property and novel functionality in the class of perovskite material. [ABSTRACT FROM AUTHOR]

In the present study, through a transmission experiment, the effects of europium complex and Eu3+ on the pearl colour in the pearl oyster Pinctada martensii were evaluated. Europium complex and europium salt were respectively enriched by dietary green algae platymonas subcordiformi, and their toxicity to algae were analysed by the 96-h acute toxic experiment. Then, the green algae enriched europium complex and europium salt were respectively fed pearl oysters for 2 months, and the surface microstructures of cultured pearls were presented with scanning electron microscopy (SEM) and atomic force microscope(AFM). The results show that toxicity of europium complex to algae is much lower than Eu3+ from lowest no observable effect concentration LNOEC values and 96h- EC50 values and two compounds can modify pearl structure and optimize pearl colour from SEM and AFM images. Taken together, our results, for the first time, show that rare earth complex can improve the pearl quality. This study provides an innovative approach for additional investigation of the influence of rare earth elements on pearls. [ABSTRACT FROM AUTHOR]

Epitaxial SrRuO3 films were grown under different oxygen partial pressures inducing different amounts of oxygen vacancies. In spite of microstructural disorders, a considerable improvement in the conductivity was observed at ambient temperature with increasing the oxygen vacancies. The oxygen vacancies are responsible for the conductivity improvement by enhancing the orbital overlap between Ru dz2 and O pz orbitals. The finding indicates that the oxygen vacancy plays an important role in determining the transport properties of perovskite oxides, by modifying their electronic structures. [ABSTRACT FROM AUTHOR]

Effects of the dopant W on the ferroelectric properties of Pb(Zr0.3Ti0.7)O3 (PZT) have been studied. The PZT and PZT doped with W (PZTW) thin films were deposited on LaNiO3 bottom electrodes by pulsed laser deposition at an oxygen partial pressure of 300 mTorr. X-ray diffraction of PZTW films revealed pure perovskite structure with increased (110) orientation, compared to that of PZT films with high (l00) orientation. Both secondary ion mass spectrometry and x-ray photoelectron spectra tests confirmed the existence of W ions in the PZTW films. Although the PZTW film showed decreased remnant polarization, the saturation polarization is increased and the coercive field was greatly lowered. Moreover, the PZTW film demonstrated an improved fatigue behavior than PZT film. The W dopants are believed to contribute to the improvement of the ferroelectric behavior of PZT thin films. Ab initio calculation indicated that the formation energy of the oxygen vacancies in PZT lattice under Pb-deficient conditions can be greatly increased by doping W, leading to a suppression of oxygen vacancy concentration. Furthermore, the W 5d states share the conduction band minimum with Ti 3d states, which helps reduce the occupation of Ti 3d states by the electrons released from oxygen vacancies. Therefore, the PZTW is less susceptible to fatigue. [ABSTRACT FROM AUTHOR]

In this work, a new nano-Bi2MoO6/diatomite composite photocatalyst was successfully synthesized by a facile solvothermal method. Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and UV-vis diffuse reflection spectroscopy (DRS) were employed to investigate the morphology, crystal structure, and optical properties. It was shown that nanometer-scaled Bi2MoO6 crystals were well-deposited on the surface of Bi2MoO6/diatomite. The photocatalytic activity of the obtained samples was evaluated by the degradation of rhodamine B (RhB) under the visible light (λ > 420 nm) irradiation. Moreover, trapping experiments were performed to investigate the possible photocatalytic reaction mechanism. The results showed that the nano-Bi2MoO6/diatomite composite with the mass ratio of Bi2MoO6 to diatomaceous earth of 70% exhibited the highest activity, and the RhB degradation efficiency reached 97.6% within 60 min. The main active species were revealed to be h+ and•O2−. As a photocatalytic reactor, its recycling performance showed a good stability and reusability. This new composite photocatalyst material holds great promise in the engineering field for the environmental remediation. [ABSTRACT FROM AUTHOR]

Herein, the authors explicitly reveal the dual-functions of N dopants in molybdenum disulfide (MoS2) catalyst through a combined experimental and first-principles approach. The authors achieve an economical, ecofriendly, and most efficient MoS2-based hydrogen evolution reaction (HER) catalyst of N-doped MoS2 nanosheets, exhibiting an onset overpotential of 35 mV, an overpotential of 121 mV at 100 mA cm−2 and a Tafel slope of 41 mV dec−1. The dual-functions of N dopants are (1) activating the HER catalytic activity of MoS2 S-edge and (2) enhancing the conductivity of MoS2 basal plane to promote rapid charge transfer. Comprehensive electrochemical measurements prove that both the amount of active HER sites and the conductivity of N-doped MoS2 increase as a result of doping N. Systematic first-principles calculations identify the active HER sites in N-doped MoS2 edges and also illustrate the conducting charges spreading over N-doped basal plane induced by strong Mo 3 d-S 2 p-N 2 p hybridizations at Fermi level. The experimental and theoretical research on the efficient HER catalysis of N-doped MoS2 nanosheets possesses great potential for future sustainable hydrogen production via water electrolysis and will stimulate further development on nonmetal-doped MoS2 systems to bring about novel high-performance HER catalysts. [ABSTRACT FROM AUTHOR]

Flower-like MWCNTs/Bi 2 O 2 CO 3 composites composed of Bi 2 O 2 CO 3 nanosheets and MWCNTs were prepared by a simple solvothermal method. These composites all showed higher photocatalytic activities than pure Bi 2 O 2 CO 3 for the degradation of RhB or 4-CP under simulated solar light irradiation. Among them, the MWCNTs/Bi 2 O 2 CO 3 composite with 3 wt% MWCNTs (M/B-3%) exhibited the highest photocatalytic activity and excellent stability. The enhanced photocatalytic performance could be attributed to the enhanced light absorption and efficient separation of photogenerated charge carriers. [ABSTRACT FROM AUTHOR]

Nutrition excess-induced inflammation positively contributed to insulin resistance. Fucoidan from sea cucumber can increase glucose translocation in skeletal muscle. However, its effects on inflammation-associated insulin resistance are not understood. We investigated fucoidan from Isostichopus badionotus ( Ib -FUC)-alleviated inflammatory response and signaling as well as -improved insulin resistance in the liver of obesity mice. The results showed that Ib -FUC reduced body weight and glucose levels, increased insulin sensitivity, and inhibited serum lipid concentrations. Meanwhile, Hepatic glycogen synthesis was promoted by Ib -FUC via activation of the PI3K/PKB/GSK-3β signaling and regulation of glucose metabolism-related enzymatic activities. Ib -FUC regulated serum inflammatory cytokines and their mRNA expression in the liver. Ib -FUC-induced inactivation of the JNK and IKKβ/NFκB pathways was involved in the activation of insulin signal cascade and inflammatory factor production. These findings suggested that Ib -FUC supplementary-induced alleviation of inflammatory response could be a mechanism responsible for its beneficial effects against hepatic insulin resistance. [ABSTRACT FROM AUTHOR]

[Display omitted] • An innovative nitrogen self-doped alveolate biochar was successfully prepared. • Samples possessed outstanding characteristics, such as OH, C O and CONH. • AKB-600 represented with the specific surface area up to 1738 m2/g. • Up to 94.61 % removal efficiency of dye was achieved during reaction system. • Nitrogen-containing and conjugated structures facilitated the actual adsorption. Novel N-doped biochar (AKB) nanomaterials derived from raw kelp root were successfully developed at different temperatures (600–1000 °C) and were used to explore the adsorption performance of cationic dye from water. Various characterization technologies including scanning electron microscopy (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD) patterns, X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR) spectroscopy and Raman spectroscopy were used to analyze the physical and chemical properties of the samples. The porosity analysis demonstrated that AKB carbonized at 600 °C (AKB-600) possessed a higher specific surface area (1738 m2/g) with a honeycomb-like microstructure. Meanwhile, AKB exhibited abundant functional groups on its surface, such as OH, C O and CONH from FT-IR and XPS analysis, resulting to the high removal efficiency of dye, up to 94.61 % at 60 min. The adsorption isotherm and kinetics data were more suitable for the Langmuir model and the Pseudo-second-order model. Electrostatic interactions and physical adsorption played dominant roles in the adsorption process, particularly, the nitrogen-containing and conjugated structures also facilitated the actual adsorption. Hence, AKB has enormous practical application potential acting as a high-effective adsorbent in the field of dye wastewater treatment. [ABSTRACT FROM AUTHOR]

• A one-step pyrolysis/activation method was used to prepare wakame biochar (AWBM). • AWBM has abundant mesopores with a high specific surface area (1156.25 m2/g). • At 293 K, the adsorption of MG using AWBM can reach 4066.96 mg/g. • The adsorption of dyes using AWBM contain physical and chemical adsorption. In this study, an activated wakame biochar material (AWBM) was prepared by a one-step calcination and activation method, whose adsorption performances for methylene blue (MB), Rhodamine B (RB) and malachite green (MG) were also analyzed. The results showed AWBM was a mesoporous fluffy structure material with a higher specific surface (1156.25 m2/g), exhibiting superior adsorption capacities for MB (841.64 mg/g), RB (533.77 mg/g) and MG (4066.96 mg/g), respectively. In addition, FT-IR analysis showed that AWBM possessed abundant active groups (such as –OH, –CO and –CH), further enhancing the adsorption efficiencies. The Langmuir model could better fit the three dyes adsorption isotherms process using AWBM, and the Pseudo-second-order model could better describe the adsorption kinetic experimental data. The thermodynamic analysis showed that the three dyes adsorption using AWBM was spontaneous endothermic reaction. This study suggests AWBM has enormous potential in the application of removing organic dyes from wastewater. [ABSTRACT FROM AUTHOR]

In this work, a SiO2-doped natural photocatalyst derived from waste mussel shell (HAS) was prepared by acidification. The as-prepared sample was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), inductively coupled plasma-optical emission spectroscopy (ICP-OES), field emission scanning electron microscope (FE-SEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR), UV-visible diffuse-reflectance spectrum (UV-vis DRS), and Differential scanning and thermogravimetric analyses (DTA/TGA). The results exhibited that HAS was mesopores nanomaterial consisting of uneven arranged rod-like structure, the dominant component of HAS was SiO2 with a large number of hydroxyl groups, and a variety of transition metals uniformly distributed in HAS. Rhodamine B (RhB) and methylene blue (MB) removal efficiencies (equal to 92.59% and 99.14%, respectively) were observed under the HAS presence when exposed to the visible light. The degradation products were analyzed using liquid Chromatograph Mass Spectrometer (LC-MS) and Total Organic Carbon (TOC), among which, MB was degraded by demethylation and deamination, and RhB was degraded by N-deethylation and conjugate structure destruction. After four successive recycles, the removal efficiency of RhB and MB are still reach 86.103% and 75.844%. This study indicated that the mussel shells might be suggested as a novel natural photocatalyst in the application of dye wastewater treatment. [ABSTRACT FROM AUTHOR]

• The novel magnetic activated biochar nanocomposites were first time prepared using wakame. • Loading nickel on the surface of wakame biochar is conducive to its recycling. • The adsorption process is a spontaneous endothermic process. • At 293 K, the maximum adsorption capacity of MB is 479.49 mg/g. In this work, magnetic wakame biochar nanocomposites for the first time had been synthesized to investigate their adsorption to methylene blue dye. As-prepared magnetic biochar samples were obtained by the impregnation method to load nickel on wakame biochar via one-step carbonization with activation agent KOH at 800 °C. The prepared samples were characterized by BET, XRD, FTIR, Raman, SEM, TEM and so on. The results exhibited that the maximum adsorption capacity of BW(Ni)0.5 to methylene blue could reach 479.49 mg/g at 20 °C. The adsorption behavior was more suitable for Langmuir isotherm equation and the kinetic data were most consistent with the pseudo second-order model. And also, the adsorption reaction was a spontaneous and endothermic process. After five cycles, it was found that BW(Ni)0.5 had a high adsorption capacity for methylene blue (117.58 mg/g). This study demonstrated that wakame biochar could have great potential in dye wastewater treatment. [ABSTRACT FROM AUTHOR]

In this study, modified activated fishbone charcoal (MAFC) was successfully prepared to remove emulsified oil from oily wastewater. Various characteristic techniques, including SEM, XRD, FTIR, and BET, were employed to investigate the morphology, texture, and surface properties of as-prepared samples. BET results demonstrated that the specific surface area of fishbone charcoal increased from 69.8 m2/g to 206.0 m2/g after treatment with K2CO3 as an activating agent, while the total pore volume of MAFC increased from 0.003 cm3/g to 0.3 cm3/g, accompanied by the formation of abundant pore structures. It was observed that 90.1% of emulsified oil (100 mg/L) was successfully removed by MAFC under our experimental conditions. The results of a kinetic and isotherm model analysis indicated that the adsorption experimental data were not only consistent with the Langmuir adsorption isotherm but were also well-described by the pseudo-second-order adsorption model. It is expected that this highly efficient and inexpensive MAFC can be a promising bio-adsorbent for removing organic pollutants from industrial wastewater. [ABSTRACT FROM AUTHOR]

This study, for the first time, rendered crab shell activated biochar modified by potassium hydroxide (KOH) impregnation (CSAB), revealing a new potential application in the removal of diesel oil from oily wastewater. The structural characteristics of crab shell biochar (CSB) and CSAB were investigated by SEM, and the crystal structure and optical properties of as-prepared samples were analyzed using XRD and FTIR. Results showed that CSAB had stratified surface structure morphology, abundant functional groups, and that its high specific surface area could reach up to 2441 m2/g, which was about eight times larger than that of untreated CSB (307 m2/g). An adsorption isotherm study indicated that the actual adsorption process both of CSAB and CSB were found to fit better with the Freundlich equation. Moreover, chemical interaction controlled the adsorption kinetics efficiency while the adsorption equilibrium capacity was 93.9 mg/g. Due to its highly developed pore structure, unique surface characteristics, and effective adsorption performance, this low-cost activated carbon had the potential to serve as an efficient adsorbent for water pollution purification. [ABSTRACT FROM AUTHOR]

The aim of this study was to optimize the adsorption performance of activated carbon (AC), derived from the shell of Penaeus vannamei prawns, on heavy metal ions. Inexpensive, non-toxic, and renewable prawn shells were subjected to carbonization and, subsequently, KOH-activation to produce nanoporous K-Ac. Carbonized prawn shells (CPS) and nanoporous KOH-activated carbon (K-Ac) from prawn shells were prepared and characterized by FTIR, XRD, BET, SEM, and TEM. The results showed that as-produced K-Ac samples were a porous material with microporous and mesoporous structures and had a high specific surface area of 3160 m2/g, average pore size of about 10 nm, and large pore volume of 2.38 m3/g. Furthermore, batches of K-Ac samples were employed for testing the adsorption behavior of Cd2+ in solution. The effects of pH value, initial concentration, and adsorption time on Cd2+ were systematically investigated. Kinetics and isotherm model analysis of the adsorption of Cd2+ on K-Ac showed that experimental data were not only consistent with the Langmuir adsorption isotherm, but also well-described by the quasi-first-order model. Finally, the adsorption behaviors of as-prepared K-Ac were also tested in a ternary mixture of heavy metal ions Cu2+, Cr6+, and Cd2+, and the total adsorption amount of 560 mg/g was obtained. [ABSTRACT FROM AUTHOR]

In this study, carbonized kelp biochar (AKB) modified by KOH impregnation and photocatalytic Bi2MoO6/AKB composite (BKBC) nanomaterials were the first time successfully synthesized for efficient removal of dyes in aqueous solution. BET, XRD, FT-IR, and SEM were employed to characterize as-prepared samples. UV-vis and other test results indicated that the removal efficiency of methylene blue (MB) was 61.39% and 94.12% for BKBC and AKB, respectively, which was up to 13 times and 20 times higher in comparison with pure Bi2MoO6 (PBM). In addition, the equilibrium adsorption capacity of MB could reach up to 324.1 mg/g for AKB. This high dyes adsorption performance could be likely attributed to its high specific surface area (507.177 m2/g) and its abundant presence of various functional groups such as –OH and =C–H on AKB. Particularly, the existing of amorphous carbon and transition metal oxides, such as Fe2O3 and Mn5O8, could be beneficial for the photodegradation of MB for AKB. Meanwhile, experimental data indicated that adsorption kinetics complied with the pseudo-second order model well, and all of the tests had satisfactory results in terms of the highly efficient adsorption and photodegradation activity of AKB nanomaterials, which suggested its great potential in wastewater treatment. [ABSTRACT FROM AUTHOR]

Biomass is known to efficiently adsorb pollutants from wastewater. In this paper, we demonstrated that a new antistatic oil-cleaning material can be prepared and assembled by using two surfactants, alkyl polyglucosides (APG) and dimethyl octadecyl hydroxy ethyl ammonium nitrate (SN), to modify calcined mussel shell powder (CMSP) through a two-step hydrotherm-assisted adsorption. The pore size and structure of CMSP was measured by BET and a contact angle meter was used to characterize the surface wetting ability. XRD, FTIR, XPS, SEM, TEM, and HRTEM were employed to determine the surface structure of CMSP modified by surfactants APG and SN (MMO). In order to further characterize properties of the surface morphology and crystal structure, the HRTEM was employed to show that the MMO surface had a single crystal structure: calcite, with a crystal plane spacing of 0.2467 nm. The surface of MMO appeared to be fluffy and disperse. The antistatic and degreasing ability of as-prepared samples (MMO) was evaluated by a ZC-36 high resistance meter and BD-457 whiteness meter. The results showed that when the calcination temperature of CMSP reached 1000 °C, and the addition amount of APG and SN was 0.8 g and 0.16 g, it had an optimum antistatic effect with a surface resistivity (Rs) of 1.35 × 108 Ω, and a detergency rate to oil of 17.35%. This study aims to embrace a green solution to reduce environmental pressure and make use of waste, which is of great significance to environmental protection. [ABSTRACT FROM AUTHOR]