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The purpose of this work is to convert organic wastewater into oxidants(H2O and CO2) to promote biomass gasification during the chemical looping process to achieve high-H2/CO-ratio syngas. A tert-butanol solution was selected as the model organic wastewater to generate enough H2O and CO2 to promote corn stalk chemical looping gasification(CLG). A series of CLG experiments was conducted at 850°C under various degrees of oxygen excess(Ω). An Ω of approximately 0.9 led to the highest hydrogen yield and fixed carbon conversion compared with the other cases. Chemometrics and thermodynamic analysis further validated the possibility of corn stalk CLG using a tert-butanol solution. The results show that CLG of biomass-organic wastewater can both treat organic waste and promote chemical looping processes.

Widespread Fe(III)-humic acid (HA) coprecipitates (FHCs) have substantial impacts on the adsorption and reduction of Cr(VI) in soils and sediments, but whether this process is equal to the sum of their individual components remains unknown. In this study, ferrihydrite (Fh)- and HA-like FHCs (C/Fe 3, respectively) were synthesized by controlling the initial C/Fe ratios (0.5–18) to explore the potential synergistic/antagonistic effects during the adsorption and reduction of Cr(VI). According to the results, antagonistic effects on Cr(VI) adsorption (5%−80%) were observed on Fh- and HA-like FHCs, where the antagonistic intensity increased with increasing HA proportions, respectively caused by the more serious occupation of adsorption sites and the stronger electrostatic repulsion to Cr(VI). Notably, significant synergistic reduction effects (5%−650%) occurred on Fh-like FHCs were found to be achieved by the activation of low-molecular HA (0.1–0.3 kDa) with primary/secondary hydroxylic groups, which might be induced by the inductive effect of Fh on complexed HA molecules according to density-functional theory (DFT) calculation. While slight antagonistic reduction effects (2%−45%) by HA-like FHCs were attributed to the decreasing accessibility of Cr(VI) to reductive phenolic groups, which might be blocked within FHC particles or complexed with Fe(III) ions through cation bridges.

International audience; Aims : Previous studies have shown that root reinforcement provided by trees could decrease over time after stem cutting. The short-term changes in root mechanical and structural traits associated with root reinforcement after stem cutting have not been fully studied. We aimed to quantify the temporal changes in root mechanical and structural traits following stem cutting, and to identify the major drivers of root reinforcement deterioration.Methods : At six elapsed times (zero, one, three, six, nine, and twelve months) after stem cutting of the species Symplocos setchuensis Brand, we measured shear strength for both rooted and root free soils, root failure modes, root mechanical traits (tensile strength, Young’s modulus, and tensile strain) and structural traits (cellulose, hemicellulose and lignin contents).Results : Both root mechanical and structural traits significantly differed as a function of root diameter and time after stem cutting. Tensile strength decreased 19.7% while Young’s modulus decreased 46.9% twelve months after stem cutting. Hemicellulose content showed the greatest decrease (45.3%) among the structural traits. The relative reduction in magnitude was higher for fine roots than coarse roots. Additional shear strength (at the yield point) provide by roots decreased 85.9% twelve months after stem cutting.Conclusions : Our findings demonstrate a higher rate of root reinforcement deterioration after stem cutting than previously reported in literatures. Our results suggest that the underlying mechanism of deterioration of root reinforcement is more likely caused by a shift of root failure from tensile breakage to slide-out failure, and a decline in root Young’s modulus.

The main challenges associated with Li-S batteries are relatively unsatisfactory cycling performance, sluggish reaction kinetics and poor utilization of sulfur cathodes especially under high current densities. Here, 3D S-CNT@MXene cages are synthesized by a simple approach that solve these problems. The 3D cages with interconnected conductive networks can improve sulfur utilization, decrease inherent resistance and enhance reaction kinetics. The ultrathin MXene shell with high surface area and plenty of terminal functional groups can prevent the aggregation of MXene, increase chemical interactions and catalytic effect with sulfur species to promote the adsorption of lithium polysulfides and the nucleation of Li2S. Moreover, the porous S-CNT sphere with sulfur nanoparticles on the surface of CNTs can facilitate electron transport, electrolyte infiltration and accommodation sulfur swelling. As a result, the 3D S-CNT@MXene cage cathode delivers a high discharge capacity of 1375.1 mAh g−1 at 0.1C, high rate capacity (910.3 and 557.3 mAh g−1 at 1.0 and 8.0 C), and excellent cycling stability. Remarkably, the composite cathode shows almost no capacity decay (656.3 mAh g−1) at a high current density of 4.0C after 150cycles, which shows the best cycling stability reported to date among all other cathodes of Li-S batteries.

A self-powered ultraviolet–visible photodetector based on NiO/Si heterojunctions made from NiO nanosheets on a Si (1 0 0) modified substrate was successfully manufactured via a facile hydrothermal method and subsequent calcination process. The fabricated detectors not only response to ultraviolet (UV) and visible light, but also possess excellent photocurrents and a lower dark current. The good performance, i.e., the external quantum efficiency (EQE) of ~22.4% and 33.1% under 350 nm and 600 nm, respectively, at zero bias, superior to most reported NiO/Si photodetectors, could be ascribed to the good crystalline NiO nanosheets and the suitable n-Si (1 0 0) substrate. Therefore, as-fabricated self-powered broadband detectors have a great potential application in wearable and portable devices.

Here, an effective approach to obtain controllable thin carbon layer encapsulated MoS2 nanospheres on the surface of interwoven carbon nanotubes to form interconnected network structure of C-MoS2/CNTs composites is presented by a facile hydrothermal method. The remarkable electrochemical performance of the resulting composites as anode electrode materials are achieved for Na-ion energy storage systems, such as excellent capacity (~468 mA h g−1 at 1.0 A g−1), high rate capability (capacity retention of ~72.8% from 0.1 A g−1 to 5.0 A g−1) and long cycling stability (100.0% capacity remaining after 1000 cycles). Systematic characterizations reveal that the outstanding performance is mainly attributed to the unique and robust composite architecture, such as, improvement the conductivity of the whole electrode material, preventing the aggregation of C-MoS2 during cycles, large atomic interface contact for Na+ storage, and providing a dense porous space to alleviate volume expansion during cycling.

Background and aims Technology involving the use of plants on slopes to prevent shallow landslides and slope instability has been extensively used worldwide. A reasonable collocation of plant and engineering measures can prevent water loss and soil erosion effectively. Because of the complicated distribution of roots in soil, there must be a simpler and more workable method of studying the role of plant roots on slope stability. The purpose of this paper is to investigate the affects of shallow-rooted plants on slope stability and provide reliable theoretical support in the process of ecological environmental constructions. Methods Here we used numerical simulations to examine the influence of plant roots on soil shear strength as the increase of soil cohesion. Then, we generalized root architecture to be soil bodies consisting of different cohesive strengths. Changes of stress and pressure were simulated within the range of soil within plant roots on the slope. The intensity attenuation method was here used to calculate the safety factor of slope. Results Tapered roots were found to be associated with more serious soil loss due to the maximal velocity of 14 m/s within the scope of plant main stems. Widely root distribution in H-type showed a cyclical effect on the slope on condition that flow shear stress was small. Conclusions Young trees have little impact on slope stability which is 3.76–7.85% merely comparing to the bare slopes regardless of rainfall. When root distributions are similar in topsoil, the resistances to the radial stress are not obvious. Widely distributed (H-type) and tapered root (VH-type) architecture are recommended in biological engineering projects.

SnS, is a promising anode material for lithium ion batteries (LIBs) and sodium ion batteries (SIBs), however, undergoes poor cyclic lifespan due to its huge volume changes and bad electroconductivity. Here, a modified CVD method is used to directly grow graphene‐like carbon film on the surface of SnS nanosheet arrays which are supported by Co‐, N‐modified porous carbon fibers (CCF@SnS@G). In the strategy, the SnS nanosheet arrays confined into the integrated carbon matrix containing porous carbon fibers and graphene‐like carbon film, perform a greatly improved electrochemical performance. In situ TEM experiments reveal that the vertical graphene‐like carbon film can not only protect the SnS nanosheet from destruction well and enhance the conductivity, but also transforms SnS nanosheet into ultrafine nanoparticles to promote the electrochemical kinetics. Systematic electrochemical investigations exhibit that the CCF@SnS@G electrode delivers a stable reversible capacity of 529 mAh g−1 at a high current density of 5 A g−1 for LIBs and 541.4 mAh g−1 at 2 A g−1 for SIBs, suggesting its good potential for anode electrodes., SnS nanosheet arrays sandwiched into the integrated carbon matrix containing porous carbon fibers and graphene‐like carbon film are prepared and provide a great improvement in the electrochemical performance of lithium ion and sodium ion batteries.