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Deviant peer affiliation (DPA) and moral disengagement (MD) play a vital role in adolescents’ cyberbullying perpetration (CP). However, moderating mechanisms underlying this association remain largely unknown. Based on the Social-ecological conceptual framework of cyberbullying (SECF-C), we tested a moderated mediating model to examine whether MD mediated the relationships between DPA and CP and whether these mediating processes were moderated by neuroticism and gender. A sample of 777 adolescents (aged from 11 to 16 years) participated in our survey. The results revealed that MD partially mediated the connections between DPA and CP. Also, neuroticism moderated the relationship between DPA and CP in adolescent boys. Finally, neuroticism and gender moderated the relationship between MD and CP, revealing the conditional indirect effects of DPA on CP via MD. The indirect impact was more pronounced for boys and high neuroticism. These mechanisms have potential implications for developing tailored interventions and preventive strategies. [ABSTRACT FROM AUTHOR]

The design and modeling of dielectric superjunction transistors using combinations of ultrahigh permittivity materials and high-mobility materials are described. We show that placing high dielectric permittivity materials in the gate–drain depletion region can reduce electric field variations by screening the field due to depleted charges. This enables simultaneously high sheet charge density and breakdown voltage for scaled field-effect transistors. Using detailed 2-D device simulation of dc and high frequency characteristics, we show that extreme dielectric constant engineering provides unique opportunities for transistor design and has the potential to perform better than state-of-the-art millimeter-wave and terahertz frequency transistors. [ABSTRACT FROM AUTHOR]

Employing the mixed ligands to react with Cd(NO3)2·4H2O afforded a new 3D coordination polymer [Cd3(BPTC)(bmp)2(ox)(H2O)4] (1) (H4BPTC = biphenyl-3,3′,4,4′-tetracarboxylic acid, bmp = 3,6-bis(imidazol-1-yl)pyridazine, H2ox = oxalic acid), in which ox2− was from the in situ oxidation of ethanol. Compound 1 bears a novel trinodal (4,6,6)-connected net structure, and it is the first replica of the theoretically predicted sqc111 topology net. Moreover, the thermal and photoluminescent properties for 1 were also investigated. [ABSTRACT FROM AUTHOR]

The sustainability of the anaerobic digestion (AD) plant was closely related to the disposal of digestate and enhancement of energy recovery. Aiming to promote this, coupling AD and digestate gasification (AD-gasification) was proposed and evaluated for a large-scale AD plant. Firstly, characterization of the solid digestate was measured. Secondly, air gasification of the solid digestate was performed. Finally, two scenarios aiming at enhancing energy recovery as electricity or gas were investigated. Superior C content (50.14 wt%), H/C (1.57) and O/C (0.62) molar ratios and lower heating value (LHV) of solid digestate (18.01 MJ/kg) made it propitious to gasification. Air gasification of digestate at 800 °C with ER = 0.26 resulted in the optimal LHV of producer gas (6.35 MJ/Nm3) and cold gas efficiency (CGE, 66.99%). In the biomass-to-electricity scenario, the excess of heat from the CHP system in the AD plant was sufficient to dry the solid digestate. Compared with the stand-alone AD plant, the total electricity from the coupling system increased about 11%. In the biomass-to-gas scenario, the gas income increased by 14% when the initial solid digestate was naturally air-dried to a water content of 50%. This research would provide technical guidance for the sustainability of the AD industry. [ABSTRACT FROM AUTHOR]

ScAlN/GaN dielectric superjunction high-electron-mobility transistors (HEMTs) with high-k passivation layer Bi1.5Zn1.0Nb1.5O7 (BZN) are demonstrated for enhancement of breakdown voltage. The BZN thin film deposited by RF magnetron sputtering has a dielectric constant of 192 after postdeposition annealing at 400 °C for 10 min. The HEMT with Lg = 200 nm and Lsd = 2.0 μ m has a maximum current density of 1.98 A/mm, a maximum transconductance of 0.52 S/mm, and a threshold voltage of Vth = −3 V. With the use of SiN/BZN/SiN sandwiched passivation layer, the average value of breakdown voltage is improved from 68.9 to 121.5 V, due to the reduction of the peak electrical field between the gate and the drain. The device has a cutoff frequency (ƒT) and maximum oscillation frequency (ƒmax) of 59 and 69 GHz, respectively. Overall, the devices exhibit a significantly higher breakdown voltage with essentially the same ƒT and ƒmax values. Pulse measurements suggest that SiN/BZN/SiN has a similar passivation effect in comparison with devices passivated by a SiN-only layer. This work demonstrates that high current and high breakdown voltage can be achieved simultaneously on semiconductor heterostructures with a high sheet charge density by integration of high-k dielectrics. [ABSTRACT FROM AUTHOR]

Fertilization will cause changes in crop growth, soil microbial community and multiple ecosystem functions, but it is unclear whether and how the optimal productivity obtained by manure application and optimizing nitrogen is driven by microbial community and ecosystem multifunctionality. We explore this mechanism based on a field fertilization experiment using a split-plot design that began in 2014 with five N rates (N0, N75, N150, N225, N300) as main plots and two manure rates (M0, NPK group; M1, MNPK group) as subplots, respectively. In general, (1) grain yield was parabolically related to the N application rate. The N rates that obtained the highest yield were 150 kg ha−1 and 225 kg ha−1 for the MNPK and NPK groups, respectively. The average yield of the MNPK group was 10.5% higher than that of the NPK group. (2) Long-term fertilization management resulted in regular changes in soil multifunctionality (SMF) and the properties of various microbial communities. The richness, network complexity and soil multifunctionality of bacterial and fungal communities also increased initially and then decreased as the N rate. On average, the response ratio of soil multifunctionality to N75, N150, N225, N300 (control is N0) and M1 (control is M0) were 0.11, 0.41, 0.53, 0.44 and 1.19, respectively. The soil multifunctionality of MNPK was 260%, 722% and 101% higher than that of NPK at the tillering, jointing and harvest stages, respectively. (3) Soil multifunctionality not only always had a significant positive effect on aboveground biomass at all growth stages, but also had significant positive correlations with bacterial richness and network complexity. Based on the existing framework, we further demonstrated that high microbial richness supports multifunctionality by ensuring strong associative complexity among microorganisms. However, only bacterial network complexity always positively drove soil multifunctionality and indirectly influenced wheat growth at all growth stages in SEMs where multiple drivers were considered simultaneously (i.e., pH, SOC and biological factors). Random forest regression analysis showed that rare bacterial taxa had stronger predictive effects on soil multifunctionality than abundant taxa. Our results validate that M1N150 can ensure high yield in the study area while maintaining a high level of ecosystem function in the soil, which also contributes to the reduction of adverse environmental risks caused by fertilizer application. Importantly, the potential of microbial network complexity, especially bacterial network complexity, to influence crop growth by driving farmland ecosystem functions deserves to be explored under different crop types, cropping systems, and irrigation conditions, compared to previous microbial richness that has been simply quantified. [Display omitted] • The yield reduction caused by excessive N application was associated with SMF. • The positive effect of SMF on wheat growth decreased with the growth stage. • Microbial network complexity predicted SMF better than diversity. • SMF driven by bacterial network complexity explains more about wheat growth. • The bacteria that have the greatest driving effect on SMF mostly belong to rare taxa. [ABSTRACT FROM AUTHOR]

We report an electron transport study of an La-doped perovskite oxide BaSnO3 thin film grown by molecular beam epitaxy on (110) DyScO3 as a function of electron concentration, by etching the film step-by-step with nanometer precision. Inductively coupled plasma-reactive ion etching with BCl3/Ar plasma is used for etching depth control. The local doping and electron density are experimentally determined after each etching step. The results show that the electron mobility is dominated by threading dislocations if the electron concentration is below 7.8 × 1019 cm−3, while ionized impurities and phonon scattering become more dominant at electron concentrations greater than 1.2 × 1020 cm−3. The charging state of thread dislocations is estimated to be 6.2. Furthermore, using the etch process to control the electron concentration and channel thickness, a gate-recessed ferroelectric field effect transistor is fabricated with 10 nm HfO2 as a gate dielectric. The device exhibits a saturation current of 29.9 mA/mm with a current on/off ratio of Ion/Ioff = 8.3 × 108 and a ferroelectric polarization charge density of 1.9 × 1013 cm−2. Under the forward gate bias sweep, the device operates in the enhancement mode with a threshold voltage of 3 V. Under the reverse gate sweeping bias, the device operates in the depletion mode with a threshold voltage of –1.5 V. [ABSTRACT FROM AUTHOR]

In this Letter, we demonstrate a Pt/BaTiO3/Al0.58Ga0.42N lateral heterojunction diode with enhanced breakdown characteristics. By using BaTiO3, a high-k material, as a dielectric material between the anode and semiconductor, the peak electric field at the anode edge near the cathode was significantly reduced and an average breakdown field exceeding 8 MV/cm was achieved for devices with an anode to cathode spacing of <0.2 μm. In contrast, Pt/Al0.58Ga0.42N control Schottky diodes displayed an average breakdown field of ∼4 MV/cm for devices with similar dimensions. The use of a high-k dielectric can more effectively utilize the high breakdown fields in ultra-wide bandgap materials by proper management of the electric field. This demonstration thus provides a framework to realize ultra-scaled lateral devices with improved breakdown characteristics. [ABSTRACT FROM AUTHOR]

Wide and ultrawide bandgap semiconductors can provide excellent performance due to their high energy bandgap, which leads to breakdown electric fields that are more than an order of magnitude higher than conventional silicon electronics. In materials where p-type doping is not available, achieving this high breakdown field in a vertical diode or transistor is very challenging. We propose and demonstrate the use of dielectric heterojunctions that use extreme permittivity materials to achieve a high breakdown field in a unipolar device. We demonstrate the integration of a high permittivity material BaTiO3 with n-type β-Ga2O3 to enable a 5.7 MV/cm average electric field and a 7 MV/cm peak electric field at the device edge while maintaining forward conduction with relatively low on-resistance and voltage loss. The proposed dielectric heterojunction could enable improved design strategies to achieve theoretical device performance limits in wide and ultrawide bandgap semiconductors where bipolar doping is challenging. [ABSTRACT FROM AUTHOR]

The development of biomass gasification is subject to low quality of gas with low heating value and high tar concentration. A new biological pretreatment method by using biogas slurry (BS) with different moisture content (40–80 wt%) and retention time (1–7 days) was advanced for promoting air gasification of corn straw (CS). The considerable NH 4 +-N, appropriate pH and abundant microbes in BS made it effective for CS pretreatment. The dry matter loss of pretreated CS was recorded, the properties of CS and the pretreated CS were comparatively analyzed, and also the kinetic studies. Air gasification experiments were performed in a horizontal tube furnace at 1000 °C. The delignification reaction of BS made disordered and incompact structure of CS with the improved surface area, and decreased the activation energy for chemical reaction. The higher moisture content and longer retention time contributed to the optimal gasification performance. Considering the time and energy conservation, the intermediate 60 wt% moisture content and retention time 5 days was proposed. Compared with the raw CS, the LHV (7.15 MJ/Nm3) increased 1.15 MJ/Nm3, and tar content decreased 21 wt%. This proved efficient and low cost to produce bioenergy from CS, meanwhile, reducing BS and minimizing its potential pollution. • BS was applied for biological pretreatment of CS before air gasification. • Insignificant dry matter loss of all pretreated samples was 1.29 wt%–5.31 wt%. • Intermediate 60 wt% moisture content and retention time 5 days was proposed. • LHV increased 1.15 MJ/Nm3, tar decreased 21 wt%. • Provide new insights for biomass pretreatment and BS disposal [ABSTRACT FROM AUTHOR]

Low photocatalytic efficiency of visible light and fast recombination of photo-generated carriers are two challenges facing the applications of photocatalyst sterilant zinc oxide (ZnO). Meanwhile, both light and dark photocatalytic activities are important. It is of great theoretical and practical significance to construct a day-night photocatalytic antibacterial material, which is beneficial to the effective use of energy and to tackle the limitation of using photocatalytic bacteriostat. ZnO nanoflowers decorated vanadium pentoxide (V 2 O 5) nanowires heterojunction (ZVH) was firstly fabricated using a facile water-bathing method. The designed ZVH structure efficiently produced abundant reactive oxygen species (ROS) in both light and darkness. It yielded 99.8% and 99.0% of antibacterial rate against S. aureus due to oxidative stress induced by ROS in light and darkness, respectively. The generation of ROS played a major role in the antibacterial activities against S. aureus under both light and dark conditions. The prepared ZVH with improved antibacterial properties provides an alternative for day-night antibacterial agents. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Stable reduced graphene oxide-cuprous oxide (rGO-Cu 2 O) nanocomposites with long-term antibacterial activities were prepared by reducing copper sulfate supported on GO using ascorbic acid as reducing agent in the presence of polyethylene glycol (PEG) and sodium hydroxide at room temperature. The rGO provided a protective barrier for Cu 2 O, preventing Cu 2 O from reacting with external solution to leach copper ions too quickly. Meanwhile, the rGO also promoted the separation of photoexcited charge carriers of Cu 2 O nanoparticles to enhance the oxidative stress reactive and protected Cu 2 O from falling apart in the phosphate buffered solution (PBS) solution to prolong the generation time of reactive oxygen species (ROS). More importantly, the large specific surface area of rGO improved the dispersibility of Cu 2 O by electrostatic interaction. The synergistic effect of sustained release of copper ions, elevated ROS production ability and uniform dispersion of rGO-Cu 2 O nanocomposites resulted in the excellent antibacterial activities of rGO-Cu 2 O nanocomposites against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) which were maintained around 70% and 65% and were increased by 40% and 35% compared with free Cu 2 O after immersing 30 days in PBS solutions. [ABSTRACT FROM AUTHOR]

Abstract Capsaicin@chitosan nanocapsules (CAP@CS) were prepared by micro-emulsion method in this work. Through transition between protonation and deprotonation of pH sensitive amino groups in chitosan, capsaicin can be triggered for self-releasing by pH changes resulted from bacterial reproduction. The total amount of released CAP@CS at pH 4 is five times more than that at pH 8.5. The CAP@CS is able to maintain the pH responsive property after 15 cycles of dialysis at pH ranging from 4 to 8.5, indicating a good cycling stability of CAP@CS nanocapsules. The bacteriostasis efficiency of CAP@CS is still up to 82.23%, 81.13% and 80.43% against adhesion of Escherichia coli (E.coli), Staphylococcus aureus (S.aureus) and Pseudomons aeruginosa (P. aeruginosa), respectively, which is caused by the repeated protonation and deprotonation of amino groups in chitosan. The prepared CAP@CS nanocapsules enable a bio-driven, intelligent and pH responsive performance for antifouling in marine applications. Graphical abstract Image 1 Highlights • pH responsive capsaicin@chitosan nanocapsules were prepared by microemulsion. • These nanocapsules presented cyclic stability under alternate pH. • The changed structure of nanocapsules was caused by the protonation and deprotonation amino groups of chitosan. • Stable pH response performance of nanocapsules prolonged the service time of outstanding antibacterial activities. [ABSTRACT FROM AUTHOR]

In the present study, we tested the mediating role of moral disengagement in the effect of childhood maltreatment on bullying and defending. We also examined whether the mediating effect of moral disengagement differed between girls and boys, early and middle adolescents, as well as only and non-only children. Five hundred and fifty-two Chinese adolescents participated in this study. The results indicated that the prevalence rates of physical abuse, physical neglect, emotional abuse, and emotional neglect were 4.0%, 40.0%, 10.5%, and 27.9%, respectively. Path analysis showed that moral disengagement partially mediated the relation between childhood maltreatment and bullying, but did not mediate the relation between childhood maltreatment and defending. Moreover, multi-group analyses indicated that no significant path in the final model differed by gender. However, early adolescents exposed to high levels of childhood maltreatment were more likely to engage in bullying and less likely to engage in defending than middle adolescents, and early adolescents with high levels of moral disengagement were more likely to engage in bullying than middle adolescents. Compared to non-only children, only children exposed to high levels of childhood maltreatment were more likely to score higher on moral disengagement and less likely to engage in defending. [ABSTRACT FROM AUTHOR]

Hg2+ contamination posed significant risks to human health and the environment even at low concentrations. And it can cause severe damage to the organs, such as kidney failure and various motor disorders. Herein, the high-performance electrochemistry sensor for Hg2+ had been designed, and the sensor properties were greatly improved, which mainly come from the introduced Schottky barrier to the CuO/Cu/PPy electrode. Benefiting from physical barrier, CuO/Cu/PPy electrode exerted charge redistribution and high Hg2+ adsorption energy, which was experimentally and theoretically proven. The analyses of mulliken charge indicated that the charge density gaps of Schottky barrier and PPy were getting bigger and bigger with the adsorption of Hg2+, which accelerated the reaction kinetics and was more conducive to Hg2+. As expected, excellent sensor capability, specifically in the sensitively detected Hg2+ in a wide linear range from 50 pM to 100 nM with a low LOD of 29.35 pM, and easily distinguish target molecules in seawater with an outstanding recovery. The experimentally and theoretically results indicated that introduced physical barrier to electrochemistry sensors was an effective means for development of novel sensors. • The reasons for the excellent sensing performance were analyzed through experiments and theoretical calculations. • A wide linear range and a low LOD were achieved. • Due to the physical barrier played a crucial role in electrochemical detection, the sensor can work in seawater. [ABSTRACT FROM AUTHOR]

The nanostructure can achieve the synergistic sterilization of electroporation and active oxygen under the action of electric field. After treatment, Escherichia coli lost a smooth cell membrane structure and had obvious electroporation holes on the surface. • The novel C/Cu 2 O-AgNPs structure are prepared by simple impregnation method. • The C/Cu 2 O-AgNPs structure electrodes have high-conductivity. • The C/Cu 2 O-AgNPs structure electrodes achieve high flow rates with low voltage. • The antibacterial mechanism of the electrode is unraveled. Water safety is closely related to the human health, an efficient and low-cost water disinfection method is far-reaching for all kinds of water supplies. However, how to achieve convenient and efficient water disinfection is still an open question. Herein, we firstly prepared a hierarchical Cu 2 O nanowires covered by silver nanoparticles-doped carbon layer on Cu foam (C/Cu 2 O-AgNPs) in a simplified one-step impregnation method. And it is confirmed that the fabricated three-dimensional structure with carbon layer which was embed into silver nanoparticles exhibits excellent conductivity than that with silver nanoparticles-loaded carbon layer. The filter combined with selected C/Cu 2 O-AgNPs materials achieved 99.6% sterilizing rate against Escherichia coli and Staphylococcus aureus under external voltage of 10 V with 1200 mL min−1 flow rates. Based on the analyses of experimental results and finite element simulations, the efficient sterilization with high flow rate comes from the strong adhesion of AgNPs embedding in the carbon layer and the enhanced conductivity of electrodes due to the improved electronic transmission in the contact of AgNPs and Cu 2 O nanowires. This rapid water disinfection will have a great potential in future practical application. [ABSTRACT FROM AUTHOR]