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Obtaining a detailed understanding of the surface modification of supports is crucial; however, it is a challenging task for the development and large-scale fabrication of supported electrocatalysts that can be used as alternatives to Pt-based catalysts for the oxygen reduction reaction (ORR). In this study, commercial silicon carbide (SiC) was modified through surface oxidization (O-SiC) to support the use of Pd nanoparticles (Pd NPs) as electrocatalysts for ORR. The obtained Pd/O-SiC catalysts exhibited better ORR activity, stronger durability, and higher resistance to methanol poisoning than that exhibited by commercial Pt/C. The role of the support in enhancing the ORR performance, especially the oxidization of SiC surfaces, was discussed in detail based on the experimental characterizations and density functional theory calculations. The underlying mechanism of the superior ORR performance of Pd/O-SiC catalysts was attributed to the charge transfer from SiCxOy to Pd NPs on the surfaces of SiC and the strong metal–support interactions (SMSIs) between Pd and SiCxOy. The charge transfer enhanced the ORR activity by inducing electron-rich Pd, increased the adsorption of the key intermediate OOH, and decreased the Gibbs free energy of the critical ORR step. Furthermore, SMSIs enhanced the ORR stability of the Pd/O-SiC catalyst. This study provided a facile route for designing and developing highly active Pd-based ORR electrocatalysts.

Chromium is a common harmful pollutant with high toxicity and low bearing capacity of soil and water. Excellent salinity resistance, a wide pH range, and high regeneration capacity were essential for qualified adsorbents used in removing hexavalent chromium (Cr(VI)) from polluted water. Herein, iron oxalate modified weak basic resin (IO@D301) for the removal of Cr(VI) was prepared by the impregnation method. The IO@D301 was characterized by scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), X-Ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). Owing to abundant amine, carboxyl groups and iron ions existing on the surface, IO@D301 possesses high adsorption and salinity resistance capacity for Cr(VI). The maximum adsorption capacity of IO301 towards Cr(VI) reached 201.30 mg·g-1 at 293 K and a pH of 5. The adsorption equilibrium was well fitted by the Freundlich model, and the adsorption process was described by the pseudo-first-order kinetics model as spontaneous and exothermic. The mechanism may be identified as electrostatic attraction, coordination, and reduction, which was confirmed by FT-IR and X-ray photoelectron spectroscopy.

In this study, a series of direct Z-scheme bismuth subcarbonate (Bi2O2CO3)/porous graphitic carbon nitride (g-C3N4) composites was prepared by using a simple two-stage template free process. The structure, morphology, textural and optical properties were characterized by X-ray diffraction, N2-physisorption, transmission electron microscopy, Fourier transform infrared spectra, X-ray photoelectron spectroscopy, UV–vis analysis and photoluminescence spectroscopy. The catalytic properties of Bi2O2CO3/porous g-C3N4 composites were assessed using tetracycline hydrochloride under simulated solar light illumination. When the loading amount of Bi2O2CO3 was 2 wt%, the composite showed the highest catalytic activity, which was 5.1 times that of porous g-C3N4 nanosheets (PCNS). The enhanced photocatalytic properties of Bi2O2CO3/porous g-C3N4 may be attributed to the formation of heterojunction between Bi2O2CO3 and PCNS, resulting in the effective separation of photogenerated carriers and enhanced absorption of visible light. Furthermore, the novel photocatalyst had an excellent catalytic stability and could be recycled for five times without distinct loss of catalytic activity.

A novel flower-like ternary Fe3O4-magnetic quantum dots / Bi2WO6/ Graphene nanosheet (Fe3O4−MQDs/Bi2WO6/GNs) composite was successfully prepared by a facile one-pot hydrothermal method. The prepared samples were characterized by XRD, FTIR, UV–vis, SEM, HRTEM, EDS, BET and VSM technologies. Compared with the Bi2WO6 and Fe3O4/Bi2WO6, the Fe3O4/Bi2WO6/GNs catalyst exhibited higher photodegradation ratio of 98.2% for methylene blue (MB) and 90% for Tetracycline hydrochloride (TC) within 210 min irradiation at pH 7, and stability over 80% even after six cycles. Characterization results showed that the enhanced photocatalytic activity was mainly due to the strong interactions of MQDs/Bi2WO6 heterojunction and high specific surface area. A possible photocatalytic degradation mechanism was proposed on the basis of the identified intermediates. Furthermore, the Fe3O4/Bi2WO6/GNs composite could be easily recovered from the reaction system under an external magnetic field owing to its sufficient magnetism, therefore which has certain potential applications in water treatment process.

Flexible touch screen panel (f-TSP) has been emerging recently and metallic nanowire transparent conductive electrodes (TCEs) are its key components. However, most metallic nanowire (MNW) TCEs suffer from weak bonding strength between metal nanowire electrode layers and polymer substrates, which causes delamination of TCEs and produces serious declines in durability of f-TSPs. Here, we introduce Ag S bonding and develop tough and strong electrode-substrate bonded MNW TCEs, which can enhance durability of f-TSPs significantly. We used silver nanowires (AgNWs) as metal conductive electrode and thiol-modified nanofibrillated cellulose (NFC-HS) nanopaper as substrates. Because of the existence of Ag from AgNWs and S from NFC-HS, strong Ag S bonding was generated and tough TCEs were obtained. The TCEs exhibit excellent electrical stability, outstanding optical and electrical properties. The f-TSP devices integrated with the TCEs illustrate striking durability. This technique may provide a promising strategy to produce flexible and tough TCEs for next-generation high-durability f-TSPs.

Myelin oligodendrocyte glycoprotein-immunoglobulin (MOG-IgG) associated disorder (MOGAD) has been recognized as a distinct disease entity with recurrent attacks. But the standard therapeutic approach to reduce relapses is unknown. Different doses of mycophenolate mofetil (MMF) are frequently used in MOGAD. We aimed to investigate the response to stratified doses of MMF in adult patients with MOGAD.We determined the frequency of relapses in patients receiving various doses of MMF treatment for MOGAD. Patients were reviewed for relapses before and during long-term treatment. Cox proportional hazards models were used to analyze the correlation between the MMF dosage and the annualized relapse rate (ARR) as well as clinical features.22 patients receiving low-dose MMF (1000 mg/day), 19 patients receiving moderate-dose MMF (1000 mg/day ≤ MMF dose2000 mg/day) and 21 patients receiving high-dose MMF (≥ 2000 mg/day) were collected in our cohort. Cox regression analysis showed that high-dose MMF treatment significantly reduced the risk of relapses (HR 0.501 [95% CI 0.268-0.934], p = 0.030) compared with low-dose and moderate-dose of MMF treatment, after adjusted by age, gender, disease duration and prednisone therapy. Patients (13/62) concomitant with autoimmune diseases, had a higher proportion of relapses (76.92%) compared with those without autoimmune diseases (18.37%) (HR = 5.96, 95% CI 1.73-20.48, p 0.001). The overall median ARR reduced from 1.13 to 0.32 under high-dose MMF treatment (p = 0.004). However, there was no significant reduction in ARR either in patients with low-dose or those with moderate-dose of MMF.This study suggests that high-dose of MMF treatment may reduce recurrent demyelinating attacks, with the lowest ARR. Randomized controlled studies are required to validate the effective therapeutic regimen.

Background Despite inclusion in neuromyelitis optica spectrum disorders (NMOSD), myelin oligodendrocyte glycoprotein antibody (MOG-Ab)-associated diseases are increasingly recognized as an independent disease entity. In this study, we conducted a systematic review and meta-analysis to comprehensively update the rate of occurrence of MOG-Ab in Aquaporin4 (AQP4)-antibody seronegative NMOSD. Methods We searched PubMed, EMBASE, and Cochrane databases for studies reporting the rates of patients with MOG-Ab in NMOSD. Fixed or random-effects models were used to pool results across studies. Results Fourteen studies met the inclusion criteria. Overall, MOG-Abs positive patients comprised 9.3% of all NMO/NMOSD (95% confidence interval [CI] 7.9%–10.8%, I2 = 13.1%), 32.5% of all AQP4-Ab seronegative NMO/NMOSD (95% CI 25.7%–39.3%, I2 = 45.8%), and 41.6% of AQP4-Ab seronegative NMOSD cases diagnosed by IPND 2015 criteria (95% CI 35.1%–48.2%, I2 = 0.0%). The pooled prevalence of MOG-Ab was 31.0% among Asian AQP4-Ab seronegative NMO/NMOSD patients (95% CI 22.1%–39.9% I2=54.1%) and 34.3% in European seronegative NMO/NMOSD (95% CI 21.9%–46.7%, I2 = 51.9%). Conclusions This study shows that MOG-Abs represent a substantial proportion of AQP4-Ab seronegative NMOSD patients despite different underlying mechanisms, clinical manifestations, and treatment response, suggesting MOG-Ab screening in AQP4-Ab seronegative NMOSD patients can facilitate accurate diagnoses and treatments.

Polymer-based thermal insulation films are widely utilized to reduce the influence of solar radiation. However, current thermal insulation films face several challenges from poor thermal insulation performance and severe environmental pollution, which are caused by the non-disintegratability of polymer substrates. Here, cellulose nanofiber (CNF)/antimony tin oxide (ATO) hybrid films with and without polyvinyl alcohol (PVA) are presented and they can be used as window thermal barrier films and personal thermal management textiles. The hybrid films exhibit prominent thermal insulation performance, blocking 91.07% ultraviolet(UV) light, reflecting 95.19% near-infrared(NIR) light, and transmitting 44.89% visible(VIS) light. Meanwhile, the hybrid films demonstrate high thermal stability, high anti-UV aging stability, and robust mechanical properties. Moreover, the used-up hybrid films based on natural cellulose are of high disintegratability and recyclability. Our present work is anticipated to open up a new avenue for the fabrication of next-generation high-performance thermal insulation films with sustainable and environmentally friendly processes.

Quizalofop-p-ethyl (C19H17ClN2O4) is a widely used herbicide for controlling annual and perennial grass weeds in broad-leaved agricultural crops. The solid–liquid phase equilibrium of quizalofop-p-ethyl in binary solvents (methanol + water and ethanol + water) was measured by using a gravimetric method from (293 to 322) K at atmospheric pressure. The results indicated that the solubility of quizalofop-p-ethyl increases with increasing temperature and decreases with increasing mass fraction of water in binary solvents. Solubility of quizalofop-p-ethyl in methanol + water and ethanol + water range from 0.0000158 to 0.0113177 and 0.000285–0.0157060 in rang of 293 to 322 K at mass fraction of water 0.10–0.60, respectively. The modified Apelblat model, λh model and Jouyban-Acree model were applied to correlate the experimental data. The strength of intermolecular hydrogen bonds were calculated by optimizing the complexes between quizalofop-p-ethyl and solvents with the B3LYP theoretic method and the 6–31 + G(d,p) basis set, which showed the bent OH···O and OH···N was −31471.040 and −33892.903 kJ·mol−1, respectively. The calculated dissolution enthalpy and entropy of quizalofop-p-ethyl in the binary solvents were positive, which indicated that the process is endothermic and increased randomness.

Hydrous iron oxide and hydrous aluminum oxide were loaded successfully onto a polymeric adsorbent (D301) to modify adsorbing materials (HIOD301 and HAOD301). The adsorptive equilibrium of atrazine was investigated in an aquatic environment using HIOD301 and HAOD301 under different experimental conditions. The results indicated that both HIOD301 and HAOD301 showed good adsorption capacities for atrazine at pH 4. The Langmuir and Freundlich isotherm equations were used to study the interactions between the adsorbate and adsorbent. The adsorption kinetics of atrazine at different concentrations was well described in terms of a pseudo-second-order equation in regard to the correlation coefficients and adsorption capacity. The removal percentages of atrazine for HIOD301 and HAOD301 were still more than 95% in the presence of sodium chloride.

Photoelectrochemical (PEC) nitrogen reduction reaction (NRR), which produces ammonia under ambient conditions by combining the merits of electrocatalysis and photocatalysis, represents an attractive prospect for nitrogen fixation. Limited by the choice of suitable p-type semiconductor, PEC nitrogen fixation should be preferentially achieved by cathodic NRR integrated with photoanode rather than direct photocathodic NRR. Even in such an approach, it still remains elusive how to design catalytically active sites on the dark cathode toward high activity and selectivity in PEC NRR. Herein, we report a new strategy for tailoring cathodic bismuth (Bi) sites with boron (B) doping and rolling curvature. The B doping in Bi matrix greatly reduces the energy barrier of the potential-determining step of N2 → *NNH in NRR while the high curvature surface on nanorolls facilitates the adsorption of N2. The integration of B doping and rolling curvature in a single cathodic catalyst boosts PEC NRR performance when combined with TiO2 nanorods array as photoanode to harvest light and provide photo-generated electrons. Such a PEC system offers an ammonia yield rate of 29.2 mgNH3 gcat.−1 h−1 and Faradaic efficiency of 8.3 % at a bias of 0.48 V versus RHE in nitrogen fixation. This work provides a guideline for the rational design of highly active and selective metallic catalyst in PEC NRR.

Commercial grade weakly basic resin D301 was impregnated with iron through a simple method using ferric chloride. Experiments for single, bisolute and trinary competitive adsorption were carried out to investigate the adsorption behavior of 2-naphthalenesulfonic acid (NSA), sulfuric acid and sulfurous acid from their solution at 298K onto the novel hybrid iron impregnated D301(Fe-D301). Adsorption affinity of NSA on Fe-D301 was found to be much higher than that of sulfuric acid, while adsorption affinity of sulfuric acid was slightly higher than that of sulfurous acid. The data of single-solute adsorption were fitted to the Langmuir model and the Freundlich adsorption model. The non-ideal competitive adsorbed model coupled with the single-solute adsorption models were used to predict the bisolute and trinary-solute competitive adsorption equilibria. The NICM coupled with the Langmuir model yields the favorable representation of the bisolute and trinary-solute competitive adsorption behavior.

Mercury(II) pollution is a growing threat to the environment and humanity. But most of the solution-based Au nanomaterial sensors suffer from low stability seriously. Here, inspired by high-affinity metallophilic Hg2+–Au(I) interaction mechanism, we introduced a transparent cellulose nanofiber matrix-supported luminescent gold nanoparticle (AuNPs) stable sensing membrane. In this solid-state membrane, the AuNPs with strong red fluorescence emission were synthesized as the sensor unit. Cellulose nanofibrilatted (CNF) matrix was fabricated as the supporting substrate. With a large specific surface area, the nanostructured CNF matrix offers abundant immobilizing spots to the sensor unit of AuNPs. More importantly, the excited fluorescence can escape directly without apparent scattering loss due to the high transparency of the CNF substrate. With strong emission of the AuNPs, coupled with abundant AuNP immobilizing spots and high transparency of the CNF substrate, the fluorescence signaling path was manipulated sequentially from signal generation, transmission until to quenching, resulting in the membrane demonstrates high sensitivity, selectivity, and stability. The detection limit of 1.0 nM is markedly lower than the threshold level of 10.0 nM permitted by US EPA. Aided with the high-performance membrane, the detection of Hg(II) becomes simple, fast, easy handing, and green. We envision the membrane will be an attractive material for Hg(II) monitor.

Background During acute attacks of neuromyelitis optica spectrum disorder (NMOSD), intravenous immunoglobulin (IVIG) maybe useful building on experience treating autoimmune disorders. Methods We conducted a retrospective study of several treatment modes for NMOSD attacks at Beijing Tiantan Hospital and Tianjin Medical University General Hospital. Clinical outcomes were defined as the short-term remission status. The good (GR), moderate (MR) or poor remission (PR) was respectively defined to triple-grade based on percentage change of initial and follow-up Expanded Disability Status Scale (EDSS) scores. Results A total of 243 attacks was analyzed in 198 patients from 2014 to 2019. Treatment groups included 153 attacks given high-dose intravenous steroids (HD-S), 14 given IVIG, 69 episodes of IVIG plus HD-S and 7 treated with plasma exchange. The proportion of patients with better outcomes were significantly lower in IVIG alone group than HD-S alone group (p = 0.004). However, sequential treatments for IVIG and HD-S yielded a higher likelihood of clinical improvement in severe attacks with EDSS ≥ 6.5 (OR = 5.85, p = 0.007). Conclusion These results did not support IVIG-alone therapy as a first-line option for acute NMOSD. However, adding HD-S to IVIG therapy was superior to HD-S alone for patients with high-onset EDSS.

The monodisperse micrometer hollow zirconia sphere was prepared in mixed solvents. It was fabricated by using the preformed poly(styrene-acrylic acid) (PSA) as template spheres which was mixed with zirconyl chloride octahydrate in ethanol solvent under steam treatment. The hollow zirconia spheres obtained by the calcination of PSA/ZrO 2 composite spheres had a narrow particle size distribution and commendable surface topography characterized by SEM. The calcined hollow zirconia spheres displayed monoclinic crystalline reflection peaks characterized by XRD. Besides, the micro-morphology, composition and molecular composition of sample were analyzed by FESEM, TG–DSC and FTIR, respectively.

Many studies have shown that LPS mainly activates four signal transduction pathways to induce inflammation, namely the p38, ERK1/2, JNK and IKK/NF-κB pathways. Studies have demonstrated that 5'-AMP-induced hypothermia (AIH) exhibits high anti-inflammatory capabilities. In this study, we explore that how AIH inhibits the inflammatory response. Wistar rats were divided into five groups: a control group, an LPS group, a 5'-AMP pre-treatment group, a 5'-AMP post-treatment group and a 5'-AMP group. For each group, plasma and lung were collected from the rats at 6h and 12h after LPS injection. ELISA assays were used to detect plasma levels of CD14, CRP and MCP-1. Inflammatory pathway activation and TLR4 expression were assayed separately by Western blot analysis and immunohistochemistry. Our results showed that rats treated with AIH either before or after an LPS-challenge had a significant decrease in plasma levels of CD14, CRP and TLR4 compared with rats that received LPS only. Western blot analysis showed that AIH inhibited the activation of extracellular signal-regulated kinases (ERK) 1/2, p38, c-Jun N-terminal kinase (JNK) and NF-κB in inflammatory rats. Our study concluded that AIH attenuated LPS-induced inflammation mainly by inhibiting activation on the ERK1/2, p38, JNK and NF-κB signaling pathways.

The solubility of N-(phosphonomethyl) iminodiacetic acid (PMIDA) in methanol, ethanol, isopropanol, 1-butanol, 1-pentanol, 1-hexanol, acetone, methylbenzene and ethyl acetate were measured over a temperature range from 293.15 to 343.15 K under atmospheric pressure. The hypothetical enthalpy of fusion and melting temperature of PMIDA were estimated. The Scatchard–Hildebrand (SH) model, the Wilson model, the nonrandom two-liquid (NRTL) model and the universal quasi-chemical (UNIQUAC) model were applied to correlate the solid–liquid equilibrium. It is shown that the Wilson model can give better results than NRTL and UNIQUAC model. The solubility parameter of PMIDA was obtained based on the SH model.

The propanoic acid 3-(hydroxyphenylphosphinyl)-monosodium salt (HPPS) and disodium salt (SHPPS) particles as most important flame retardants were synthesized by 3-(hydroxyphenylphosphinyl)-propanoic acid with sodium hydrogen carbonate at room-temperature and characterized. The solubility of HPPS and SHPPS in pure water, methanol, ethanol, acetone, acetic acid and ethyl acetate were measured over a temperature range from 293.15 to 343.15 K under atmospheric pressure. Furthermore, the solubility of HPPS in mixed waters (ethanol + water) was determined and found to exhibit a synergistic effect. The two models, including the modified Apelblat model and the Scatchard–Hildebrand model were applied to correlate the experimental solubility data. The calculated solubilities are in good agreement with the experimental results.

The novel flame retardant aluminum diisobutylphosphinate was synthesized and its structure was identified and studied by elemental analysis, infrared spectroscopy (IR) and X-ray diffraction (XRD). Thermal degradation behaviors of the novel flame retardant in a nitrogen atmosphere were studied using thermogravimetric analysis (TGA) techniques. The kinetic parameters, including the activation energy and frequency factor of the decomposition process for the title compound were calculated through the Friedman and the Kissinger–Akahira–Sunose (KAS) methods and the thermal decomposition mechanism was also studied with the invariant kinetic parameters (IKP) method based on a set of TGA data obtained at different heating rates. It was shown that the activation energies calculated for the decomposition reaction by different methods were found to be consistent and the conversion functions calculated by means of the IKP method depend on a set of kinetic models.

Solid–liquid equilibrium (SLE) data for the glyphosate in methanol, ethanol, n-propanol, 2-propanol, acetone, benzene and ethyl acetate, and aqueous sodium chloride solutions were measured with a temperature range from (283 to 352) K. The hypothetical enthalpy of fusion and melting temperature of glyphosate were estimated. The Wilson model, the nonrandom two-liquid (NRTL) model, the universal quasi-chemical (UNIQUAC) model, and the Scatchard–Hildebrand (SH) model were applied to correlate the solid–liquid equilibrium. It is shown that the Wilson model can give better results than NRTL and UNIQUAC model. The solubility parameter of glyphosate was obtained based on the SH model. In aqueous sodium chloride solutions, the solubility of glyphosate increases with the molality of sodium chloride increasing. The system of glyphosate + sodium chloride + water is found to exhibit a synergistic effect.

This paper introduces a versatile approach for the modification of terylene microporous membrane by PVA-MS layer-by-layer self-assembling to improve its filterability. The preparation conditions including filtration time of the first HTAB layer, reaction time and bilayer number were investigated. The results suggested that suitable filtration time of the first HTAB layer was 8 min and the reaction time was 10 min with suitable HTAB/PVA-MS bilayer numbers. Membrane chemistry, morphological changes and hydrophilicity of the composite membrane were characterized in details by FTIR-ATR spectroscopy, scanning electron micrograph and water dynamic contact angle measurements. Results revealed that PVA-MS could be adsorbed mainly on the surface of the terylene microporous membrane and dynamic contact angle on the terylene microporous membrane surface decreased with the increase of bilayer numbers indicating an enhanced hydrophilicity for the modified terylene microporous membrane. Backwash experiments of composite membranes exhibited much higher stability of the HTAB/PVA-MS active layer. The permeation flux of activated sludge was measured to evaluate the anti-fouling property of composite membranes, and the results showed an enhancement of anti-fouling property of modified composite membranes.

A micron-sized LiFePO4/C composite with a spherical morphology was reduced carbothermally from precursor particles prepared by ball milling-assisted spray-drying. The specific capacity of the electrode at a 10 C (1700 mA/g) rate was 110 mAh/g and a high voltage plateau was achieved. The high-rate performance of the composite electrode was due to its unique spherical structure, comprising clusters of nano- or sub-micron-sized spherical particles. This morphology increases the effective conductive surface area, reduces the charge-transfer reaction resistance and improves the diffusion of lithium ions.