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Good porous structure and pseudocapacitive active heteroatoms play a key role in boosting the electrochemical characteristics of graphene materials. In this work, nanocellulose/B, N, F tri-doped graphene composite hydrogels (NTGHs) are prepared via an easy hydrothermal process, in which graphene oxide (GO), ammonium fluoroborate and nanocellulose (NC) are utilized as structure regulator, dopant and spacer, respectively. The NTGHs exhibit medium-specific surface area, big packing density, high heteroatomic content, and dense porous structure with good hydrophilicity. As a result, the symmetric aqueous supercapacitor (SASC) based on the optimal sample NTGH-75 display remarkable gravimetric (268.8 F g−1) and volumetric (311.8 F cm−3) specific capacitance, excellent rate capability (81.6 % capacitance retention at 10 A g−1) and long lifespan. In particular, the all-solid-state supercapacitors (ASSC) assembled by NTGH-75 also presents high specific capacitance (177.8 F g−1), favorable impedance characteristics, and good cycle stability. The synthesis strategy in this paper provides new inspiration for the application of graphene-based electrode materials. • Dense graphene composites hydrogels are easily prepared. • Nanocellulose was used as spacer and electrolyte transport channel. • Heteroatom doping gives the sample good pseudocapacitance characteristics. • Excellent gravimetric and volumetric electrochemical property is achieved. [ABSTRACT FROM AUTHOR]

Previous studies showed a vitamin D deficiency in patients with Behçet's disease, suggesting potential benefits of vitamin D supplementation in the prevention and treatment of Behçet's disease. Interpretation of these studies may be limited by reverse causality or confounding bias. We aim to determine the causal association between serum 25-hydroxyvitamin D [25(OH)D] and the risk of Behçet's disease by Mendelian randomization. An allele score formed by four variants (rs2282679, rs10741657, rs12785878 and rs6013897) that were associated with serum 25(OH)D level, was examined using data of genome-wide association study (GWAS) on 999 Behçet's disease and 4417 healthy individuals of Chinese ancestry and validated using data of GWAS on 1215 Behçet's disease and 1278 controls of Turkish ancestry. The primary outcome was the risk of Behçet's disease, evaluated by an inverse variance weighted average of the associations with genetically determined 25(OH)D levels. The inverse variance weighted estimate showed that genetically increased 25(OH)D level was associated with a higher risk of Behçet's disease. In the Chinese cohort, the odds ratio for Behçet's disease in one standard deviation increase of natural log-transformed 25(OH)D level was 3.82 (95% CI: 1.27–11.42). Data from Turkish cohort confirmed the association with Behçet's disease (OR, 95% CI: 4.18, 1.15–15.12). In overall combination of Chinese and Turkish cohorts, the odds ratio for Behçet's disease per standard deviation increase of natural log-transformed 25(OH)D level was estimated to be 3.96 (95% CI: 1.72–9.13; P = 0.001). No significant evidence of pleiotropy and heterogeneity was detected. On the basis of evidence in 7909 human beings, this study provides the newest indication that a lifelong higher 25(OH)D level is associated with an increased risk of Behçet's disease. Special attention should be paid to the potential harm of long-term or high-dose use of vitamin D supplements in clinical practice. [ABSTRACT FROM AUTHOR]

Titanium carbide is a good candidate for tritium permeation barrier in a fusion reactor. However, its oxidation susceptibility and the mismatch between the ceramic coating and substrate are still a challenge. In this study, a promising candidate as a hydrogen permeation barrier, comprising a titanium-based ceramic TiO 2 /TiC x composite coating, was proposed. The preparation process of this TiO 2 /TiC x composite coating involves two steps of carbon ion implantation and oxidation under ultra-low oxygen partial pressure. According to the results, the optimal oxidation temperature for TiO 2 coating is 550 °C, with the increase of the oxidation temperature, the particles on the surface of the oxide layer become coarse and loosely arranged, and the protective performance of the oxide layer is greatly reduced. The hydrogen barrier permeation behavior of the composite coating in a fusion reactor was simulated via hydrogen plasma discharge environment, the results show that the hydrogen barrier permeation performance of the composite is significantly better than that of a single TiO 2 coating. In addition, the coatings treated with hydrogen plasma showed a certain self-repairing performance through the diffusion growth of the TiC x layer. These findings illustrate a novel method for preparing composite coatings to restrain hydrogen permeation, providing insight into the development of hydrogen permeation barrier materials. Image 1 • A TiO 2 /TiC x composite coating was fabricated by C ion implantation. • Suitable oxygen potential can passivate TiC x from being over-oxidized. • This new coating has excellent hydrogen permeation barrier performance. [ABSTRACT FROM AUTHOR]

To simulate and investigate the irradiation damage of neutron and transmutation effect (He production) on the hydrogen isotope trapping behavior, in the present study, a new monoclinic hydrogen permeation barrier composed of Cr 2 O 3 was fabricated and helium implantation with different fluences was tentatively employed. First, pure chromium samples were oxidized in an ultra-low oxygen partial pressure (1.7 × 10−23 Pa) environment to obtain a single Cr 2 O 3 layer. Then a dense layer of helium bubbles was formed in a substrate using a helium ion implantation method. Finally, the samples were treated in a hydrogen plasma environment at 500 °C. The damage, vacancy, and helium distribution in these samples were then simulated by SRIM. The morphology, phase, surface characteristics, thermal desorption, and electrochemical properties were subsequently characterized and evaluated. Thermal desorption spectrum analysis (TDS) was used to study the thermal desorption of hydrogen and helium at different temperatures. Our results showed that the inhibitory effect of the composite hydrogen barrier layer on the hydrogen diffusion in the substrate first increased and then decreased with the increase of the helium ion implantation fluence. Image 1 • A dense Cr 2 O 3 film was successfully fabricated in an ultra-low O 2 environment. • Helium was implanted to investigate its defect and trapping behavior. • Results indicated that helium has significant effect on hydrogen retention. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, a two-dimensional (2D) dynamic model of root water uptake was proposed based on soil water dynamic and root dynamic distribution of grapevine, and a function of soil evaporation related to soil water content was defined under alternate partial root-zone drip irrigation (APDI). Then the soil water dynamic model of APDI (dynamic APRI-model) was developed on the basis of the 2D dynamic model of root water uptake and soil evaporation function over the growing season. Soil water dynamic in APDI was respectively simulated by dynamic and static APRI-models. The simulated soil water contents by two models were compared with the measured value. Results showed that values of root-mean-square-error (RMSE) for dynamic APRI-model were less than that of the static APRI-model either in the east side or the west side of grapevine. The average relative error between the simulated and measured value was less than 5% for dynamic APRI-model, indicating that the dynamic APRI-model is better than the static APRI-model in simulating the soil moisture dynamic throughout the growing season under the APDI. [Copyright &y& Elsevier]

Postoperative cognitive dysfunction (POCD) is characterized by impaired learning and memory. 6 h duration isoflurane anesthesia is an important factor to induce POCD, and the dysfunction of ryanodine receptor (RyR) in the hippocampus may be involved in this process. We investigated the expression of RyR3 in the hippocampus of mice after 6-h duration isoflurane anesthesia, as well as the improvement of RyR receptor agonist caffeine on POCD mice, while attempting to identify the underlying molecular mechanism. We constructed a POCD model using 8-week-old male C57BL/6J mice that were exposed to 6-h duration isoflurane. Prior to the three-day cognitive behavioral experiment, RyR agonist caffeine were injected. Fear conditioning and location memory tests were used in behavioral studies. We also exposed the mouse neuroblastoma cell line Neuro-2a (N2A) to 6-h duration isoflurane exposure to simulate the conditions of in vivo cognitive dysfunction. We administered ryanodine receptor agonist (caffeine) and inhibitor (ryanodine) to N2a cells. Following that, we performed a series of bioinformatics analysis to discover proteins that are involved in the development of cognitive dysfunction. Rt-PCR and Western blot were used to assess mRNA level and protein expression. 6-h duration isoflurane anesthesia induced cognitive dysfunction and increased RyR3 mRNA levels in hippocampus. The mRNA levels of RyR3 in cultured N2a cells after anesthesia were comparable to those in vivo, and the RyR agonist caffeine corrected the expression of some cognitive-related phenotypic proteins that were disturbed after anesthesia. Intraperitoneal injection of RyR agonist caffeine can improve cognitive function after isoflurane anesthesia in mice, and bioinformatics analyses suggest that CaMKⅣ may be involved in the molecular mechanism. Ryanodine receptor agonist caffeine may improve cognitive dysfunction in mice after isoflurane anesthesia. • 6-h duration isoflurane anesthesia induced cognitive dysfunction and increased RyR3 mRNA levels. • RyR agonist caffeine improves isoflurane-induced cognitive dysfunction and expression of its related phenotypic proteins. • Bioinformatics analyses suggest that CaMKⅣ may be involved in the molecular mechanism. [ABSTRACT FROM AUTHOR]

The design and fabrication of segmented ship models have great effects on wave-induced loads in wave basins. Three different segmented ship models of a 20,000 TEU (twenty-feet equivalent unit) ultra-large container ship are designed and fabricated with different support frames and backbones. The shell and wooden frames of Models A and B were fabricated with the same method, however, the type of backbone and scale are different. Model C is a steel framing model, the dimensions of the frame members are validated by finite element method and the frame members are connected with welding technique. Suitable parameters are selected to design and fabricate Model C with the improved fabrication method. The calculated mode results of Model C are compared with the experimental data to validate the reasonability and advantage of the improved design and fabrication method. The dry and wet modes of the three ship models are measured and compared. The three different ship models are tested under typical conditions in different wave basins, and the corresponding test results are compared to reveal the effects of the fabrication method on structural elastic modes and wave-induced loads. Finally, the uncertainty analysis of the three model tests under typical conditions are conducted. • Three different scaled segmented ship models were designed and fabricated. • Effects of three important parameters were investigated. • Three different ship models were tested under typical conditions in different wave basins. [ABSTRACT FROM AUTHOR]

Hydrodynamic and hydroelastic responses of a large container ship advancing forward in head regular waves are analysed by experimental study and three-dimension (3D) linear frequency domain hydroelasticity theory. A set of model tests for a 20,000 TEU containership were carried out to investigate the ship hydroelastic characteristics in the seakeeping wave basin of CSSRC. The natural frequency and modal ship were measured and validated by a 3D finite element model. Two 3D linear frequency domain hydroelasticity theories, a pulsating source Green's function method and a translating pulsating source Green's function method were used to investigate the influence of the forward speed on hydrodynamic coefficients, motion responses and vertical bending moments at midship. Four speed cases were examined in the study. The numerical results were compared with the experimental data and good agreement was obtained. The wave-induced load linearly increases with the growth of the forward speed. The performance of the two different Green's function methods on the hydrodynamic and hydroelastic response of the large containership with different forward speed was also investigated. • Aim to investigate hydrodynamics and hydroelasticity of a large containership. • The speed influence on ship motions is investigated. • Ship hydroelastic responses are investigated by experimental and numerical approaches. • The performance of the two Green's function methods is analysed. [ABSTRACT FROM AUTHOR]

Iron-nickel based stainless steel (SS) applied in nuclear plants as a substrate material barely suppresses the permeation of hydrogen plasmas, which are mainly composed of positive and negative hydrogen ions with trace amounts of non-ionized hydrogen atoms. In this work, a new Cr 2 O 3 /Al 2 O 3 bipolar oxide barrier was prepared using atomic layer deposition (ALD) of Al 2 O 3 on a Cr 2 O 3 layer that was generated by removing partial oxides with cyclic voltammetry (CV) of SS that had been pre-oxidized at 550 °C in air. We found that a small layer of α-Al 2 O 3 was formed by the template effect of Cr 2 O 3 at the interface of this composite film. The hydrogen permeation behavior of this bipolar oxide barrier in a fusion reactor was simulated with hydrogen-discharging plasma treatment. The results demonstrated that the hydrogen permeation resistance of this bipolar oxide was superior to the original oxide or a Cr 2 O 3 film. Impressively, hydrogen plasma treatment repaired the bipolar oxide via reduction of the defective CrO 3 , resulting in an improvement in the hydrogen permeation resistance. These findings demonstrate a novel method of hydrogen permeation barrier preparation on SS, providing insight into hydrogen barrier construction for future nuclear energy applications. Image 1 • A new Cr 2 O 3 /Al 2 O 3 coating is prepared by selective removal of oxides and ALD. • α-Al 2 O 3 is formed at the interface by the template effect of Cr 2 O 3. • The bipolar oxide exhibits excellent hydrogen permeation resistance. [ABSTRACT FROM AUTHOR]

Abstract Ceramics are the most promising candidates for tritium permeation barriers for fusion reactors due to their high thermal and chemical stabilities and low hydrogen isotope permeation reduction factors. However, hydrogen embrittlement and a large number of defects in ceramic coatings are new challenges for first wall materials in nuclear reactors. To address this issue, a new Cr 2 O 3 Y 2 O 3 coating with a thickness of about 100 nm was synthesized and placed in an ultra-low oxygen partial pressure (8 × 10−20 Pa) environment, in which a compact Cr Y alloy coating was successfully deposited on the stainless-steel substrate by pulsed electrochemical deposition. The interactions between the coating and hydrogen plasma were comprehensively analyzed and compared via surface analysis techniques, including TEM, XPS and electrochemical impedance spectroscopy (EIS). The mechanical properties of the coating before and after hydrogen permeation were studied by tensile testing. It was found that this ceramic coating effectively reduced the defect concentration and retained a high protective performance upon hydrogen exposure. Therefore, this new Cr 2 O 3 Y 2 O 3 coating has potential as a promising hydrogen permeation barrier. Graphical abstract Image 1 Highlights • The Cr 2 O 3 Y 2 O 3 coatings were successfully synthesized in an ultra-low P o 2. • This new coating effectively reduced the Cr vacancies due to the presence of Y ions. • Improved hydrogen permeation resistance and the tensile strength of the SS have been obtained. [ABSTRACT FROM AUTHOR]

Highlights • The genotoxicity of Titanium dioxide nanoparticles (TiO 2 -NPs) was evaluated. • TiO 2 -NPs did not induce gene mutations in mouse lymphoma L5178Y cells. • TiO 2 -NPs did not induce reverse mutation in the bacterial strains.. • TiO 2 -NPs cannot be classified as mutagenic and require further confirmatory studies. Abstract Titanium dioxide nanoparticles (TiO 2 -NPs) are widely used in the cosmetics, health, and food industries, but their safety and genotoxicity remain a matter of debate. We investigated whether TiO 2 -NPs could induce gene mutations in mouse lymphoma L5178Y cells and Salmonella typhimurium strains TA97a, TA98, TA100, TA102, and TA1535. Following preliminary tests, 2 mg/mL for the mouse lymphoma gene mutation assay and 1.25 mg/plate for the in vitro bacterial reverse mutation assay (Ames test) were selected as the highest concentrations. Exposure to TiO2-NPs for 4 or 24 h with or without S9 metabolic activation did not increase mutation frequency for any of the concentrations tested in L5178Y cells. In the Ames test, TiO 2 -NPs did not induce reverse mutation in the bacterial strains. No positive mutagenic responses were observed in either test system, and therefore we cannot classify TiO 2 -NPs as mutagenic; further testing will be required to determine conclusively whether TiO 2 -NPs are genotoxic. [ABSTRACT FROM AUTHOR]

Abstract Metal oxides and carbides are promising tritium permeation barrier coatings for fusion reactors. However, the thermomechanical mismatch between the coating and substrate poses a threat to their interface's integrity during fabrication and operation. To address this issue, a metallic interlayer coating was introduced followed by selective oxidation in which a compact and uniform Cr C amorphous alloy coating was successfully deposited on the stainless steel substrate by pulsed electrochemical deposition. A new composite coating of Cr x C y @Cr 2 O 3 /Al 2 O 3 was formed by subsequent controlled oxidation conversion and atomic layer deposition. The phase, morphology, chemical state and defects of the films were analyzed and compared both before and after hydrogen exposure at 300 °C. The results show that this new kind of composite coating, based on the principles of grain boundary pinning of chromic oxide with carbide and defect healing of alumina, can remarkably improve the hydrogen permeation barrier performance of these materials. Highlights • A new ceramic coating based on grain boundary pinning and passivation for hydrogen permeation barrier was proposed. • The Cr x C y @Cr 2 O 3 /Al 2 O 3 coating was successfully fabricated by selective oxidation of a Cr C alloy and atomic layer deposition. • This composite coating demonstrates improved and repair performance upon hydrogen exposure. [ABSTRACT FROM AUTHOR]

A succession of Zr-based porphyrinic metal-organic frameworks (Zr-MOFs) are synthesized with metalation and utilized as adsorbents for removal of the cationic dye malachite green (MG) and the anionic dye methyl orange (MO). Results show the optimal adsorbent is MOF-525(Co) and the removal efficiencies for MG and MO by MOF-525(Co) are 99.0% and 90.5% at 60 min as the initial dye concentration is 100 mg L−1. The N 2 adsorption/desorption results indicate the high surface area, micropore of MOF-525(Co); the FT-IR spectra and adsorption thermodynamics results demonstrate that the adsorption mechanisms of both MG and MO by MOF-525(Co) belong to the π-π stacking interactions of physical adsorption, and the hydrogen bonds and Co–O bond of chemical adsorption. Additionally, the optimal pH of dye adsorption is 7.0 for MG and 3.0 for MO, and the adsorption capacities of MG and MO decrease in saline solution. The adsorption kinetics reveal that the pseudo-second-order kinetic model is better for illustrating the adsorption performances of both dyes by MOF-525(Co); the adsorption isotherm models suggest that the Freundlich model is fitted for MG adsorption but the Langmuir is fitted for MO. Furthermore, the adsorption processes can be demonstrated as spontaneous, exothermic for MG with negative entropy but endothermic for MO with positive entropy by thermodynamics data. In conclusion, MOF-525(Co) possesses a significant adsorption ability and excellent reusability for MG, and it could be a promising adsorbent for MG removal. [Display omitted] • The removal efficiencies of MG and MO by MOF-525(Co) are 99.0% and 90.5% at 60 min. • The optimal pH of dye adsorption is 7.0 for MG and 3.0 for MO. • The adsorption performances of both dyes are the pseudo-second-order kinetic model. • The Freundlich model is fitted for MG adsorption but the Langmuir is fitted for MO. • The mechanisms of both dyes adsorption on MOF-525(Co) are the π-π stacking interaction, hydrogen bond, and Co–O bond. [ABSTRACT FROM AUTHOR]

Abstract: In alternate partial root-zone irrigation (APRI) a significant amount of irrigation water can be saved without considerable yield reduction. In this paper, HYDRUS-2D/3D was used to investigate the impact of geometric design of alternate partial root-zone subsurface drip irrigation (APRSDI) with brackish water for growing tomato on soil moisture and salinity distribution. Three inter-plant emitter distances (IPED; 20, 30, and 40cm), two emitter depths (10 and 20cm), and three irrigation water salinity levels (0, 1, and 2dSm−1) were used to implement the proposed simulation scenarios in loamy sand soil during a 40-day simulation period. The simulation results showed that higher soil moisture content was found beneath the plant trunk in case of 20cm (short IPED) and near the domain border in case of 30 and 40cm IPED. Short IPED guarantees more water in the maximum root density zone. A deeper wetting front occurred for deep emitter depth, while the wetting front reached the soil surface for shallow emitter depth. Salinity results revealed that as irrigation water salinity increased, the salinity in the top soil increased. In addition, the salinity at the soil surface increased as IPED and emitter depth increased. Higher root water uptake rates were recorded in the case of 20cm IPED while the emitter depth did not show any considerable effect on root water uptake rates. Moreover, the applied irrigation water was fully consumed by the plant in case of short IPED. Emitter depth and salinity of irrigation water had negligible effect on amount of irrigation water extracted by plant roots and percolated amount below the bottom boundary of the flow domain. Overall, short IPED is recommended in APRSDI with or without brackish irrigation water regardless of the emitter depth. [Copyright &y& Elsevier]

• The content of α-Al 2 O 3 was significantly increased in ultra-low partial pressure. • Low partial pressure promoted the near-stoichiometric Cr 2 O 3 phase. • Reduced formation temperature of α-Al 2 O 3 was due to the Cr 2 O 3 template. α-Al 2 O 3 is one of the most promising hydrogen permeation barriers due to its high melting point, stable chemical properties, and good machinability. However, α-Al 2 O 3 synthesis usually requires temperatures above 1200 °C, which weakens the properties of the substrate material. Therefore, low-temperature preparation of α-Al 2 O 3 is crucial. Most studies have reported that using Cr 2 O 3 as a template is a good method to promote α-Al 2 O 3 formation. However, the formation of monolithic Cr 2 O 3 is still a challenge. To address these problems, a Cr/Al coating was introduced that was successfully deposited on stainless steel. A new composite coating was formed by the subsequent oxidation conversion under ultra-low-partial-pressure conditions via decomposing the oxygen precursors (nickel/iron oxide) in a closed environment. The results from X-ray diffraction, Raman spectra and other methods showed that the content of α-Al 2 O 3 was enhanced at 2.6 × 10−24 Pa (theoretical calculation value) and promoted the formation of near-stoichiometric Cr 2 O 3. In addition, the ultra-low partial pressure condition could promote the diffusion of defects on the interface between metastable Al 2 O 3 and corundum crystal structure Cr 2 O 3 , by which the α-Al 2 O 3 was successfully formed at 600 °C due to the template effect of Cr 2 O 3. This work provides a new approach for the low-temperature preparation of α-Al 2 O 3. [ABSTRACT FROM AUTHOR]