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Ni–Fe–Sn electrocatalyst supported on nickel foam (Ni–Fe–Sn/NF) with high efficiency of hydrogen evolution reaction (HER) has been successfully fabricated through one-step potentiostatic electrodeposition route. The optimized Ni–Fe–Sn/NF displayed an extremely low overpotential of, respectively, 144 and 180 mV at 50 and 100 mA cm−2 for HER in alkaline condition. Moreover, it could retain its superior stability for at least 12 h. The remarkable electrocatalytic activity of our electrocatalyst is ascribed to the high conductivity originated from synergistic effects between Ni, Fe, and Sn during HER process.

To increase the conductivity of proton exchange membranes in the membrane thickness direction, a novel mixed matrix membrane of Nafion ionomer and sulfonated graphene nanoplates (sGNP) with aligned proton channels is prepared with the assistance of an electric field. A high voltage alternative electric field is applied to a casting solution consisting of Nafion ionomer, sGNP, N, N-dimethylformamide (DMF), and p-xylene (PX) while evaporating the solvents. The sGNP, naturally attracting the ionic groups of Nafion ionomer to their vicinity, is polarized and rotated under the electric field, leaving aligned proton channels in the solidified membrane. The trans-plane proton conductivity of the mixed matrix membrane can reach 0.155 S cm−1 at 80 °C and 100% RH, an increase of 48% as compared with the conventional cast Nafion membrane. Accordingly, the peak power output of H2/O2 fuel cell with the mixed matrix membrane increases by 15%, reaching 440 mW cm−2 at 80 °C.

Rabeprazole sodium is a widely used drug for gastrointestinal disorders. Several analytical methods for identifying rabeprazole sodium and its impurities have been reported. However, the genotoxici...

Anatase/rutile titanium dioxide (TiO2) with heterophase junction and large Brunauer-Emmett-Teller (BET) specific surface area (50.1 m2 g−1) is successfully synthesized by calcinating Materials of Institut Lavoisier-125(Ti) (MIL-125(Ti)) with 30% O2/Ar at the temperature of 600 °C (M−O−600). Several techniques are used to examine the physicochemical, photoelectrochemical and optical properties of samples, and their photocatalytic performances are evaluated by photodegradation of gaseous toluene and liquidus tetracycline (TC) under visible light illumination. It is found that the calcination temperature has significant influence on the crystal structure and physicochemical parameters of TiO2. The weight fractions of rutile and anatase TiO2 of M−O−600 are approximately 0.7 and 0.3, which displays outstanding photocatalytic activity. Through the construction of heterophase junction, M−O−600 has better oxygen adsorption and higher density of localized states, which effectively promotes the generation of superoxide radical (·O2–) and hydroxyl radical (·OH) species. In-situ infrared spectra indicate that toluene is oxidized to benzyl alcohol, benzaldehyde and benzoic acid in turn and then oxidized to formic acid and acetic acid before eventually degraded into H2O and CO2. Gas chromatography-mass spectrometry (GC–MS) is also used to further investigate the degradation pathway of toluene. Degradation pathway and mechanism of TC are studied by liquid chromatography-tandem mass spectrometry (LC-MS). Moreover, three-dimensional excitation-emission matrix fluorescence spectroscopy (3D EEMs) and total organic carbon (TOC) show that TC can be effectively mineralized through a series of reactions by M−O−600 during photocatalysis.

Superhydrophobic surfaces – driven from natural biology – are being increasingly studied in many engineering fields. This study fabricated hydrophobic AAO/Ni coatings and superhydrophobic AAO/Ni/Ni...

Ambient fine particulate matter (PM2.5 ), as one of the predominant air pollutants, has achieved effective control in recent years in China. Whether the use of indoor air purifiers is still necessary needs further exploration. A randomized crossover trial was conducted in 54 healthy students in Beijing, China. Participants were randomized assigned to the use of real or sham high-efficiency particulate air filter (HEPA) for a week and changed the status after a washout period. Health measurements of cardiorespiratory biomarkers were performed at the end of each period. Linear mixed-effects models were used to evaluate the association between PM2.5 exposure and cardiorespiratory biomarkers. Compared with sham air purification, average diastolic blood pressure (DBP), fractional exhaled nitric oxide (FeNO), and 8-isoprostane (8-isoPGF2α) levels decreased significantly in the real purification. The effects of indoor air purification on lung function indicators including forced expiratory volume in one second (FEV1 ), peak expiratory flow (PEF), and forced expiratory flow between the 25th and 75th percentile of forced vital capacity (FEF25%-75% ) were also significant. Our findings showed a protective effect of indoor HEPA air purifiers on cardiorespiratory health of young healthy adults reflected by the decreased blood pressure, respiratory inflammation, and systematic oxidative stress and improved lung function.

The fabrication of flexible electronic sensors with self-healing capability is of great importance for the applications in wearable devices and skin-like electronics. Herein, a molybdenum disulfide (MoS2) nanosheets-based hydrogel (Gel-PEG-MoS2, GPM hydrogel), with near infrared (NIR) light-induced self-healing property, was first reported as a flexible sensor. Only a small amount of MoS2 nanosheets (0.04 wt‰) could impart the hydrogel with fast self-healing property under NIR irradiation in 90 s. The healing efficiencies increased with the increasing of MoS2 loadings. Moreover, the GPM hydrogel exhibited both contact and noncontact sensing properties based on its deformation-dependent and light-sensitive conductivity, showing potential application as mechanical sensor and light-activated switches. By employing the versatile MoS2 nanosheets, the hydrogel exhibited both fast self-healing ability and mechanical/light sensing capability. Therefore, the MoS2-based hydrogel provides a two-pronged approach for construction of self-healing flexible electronics.

Based on the historical documents of Ming and Qing dynasties, with the help of mathematical statistics and the ArcGIS spatial analysis method, this study reconstructed grades and counties affected by locust plagues to examine their spatiotemporal characteristics, environmental significance and social impact. The results show that: (1) There were 242 locust plague years in the Xiang-E-Gan region during the Ming and Qing dynasties, with an average of one outbreak every 2.25 years. The Qing dynasty suffered more than the Ming dynasty, and Hubei Province was affected more seriously than Jiangxi Province and Hunan Province. Locust plagues mostly occurred from March to August, and autumn locust plagues occurred more frequently than summer locust plagues. (2) The sixteenth, seventeenth and nineteenth centuries were periods of successive outbreaks, with 4.13 locust plague years and 10.75 affected counties per decade. The spatial heterogeneity and aggregation of locust outbreaks were significant, and the plain area was affected more seriously and continuously. (3) Low temperature promoted the outbreak of locust plagues, especially during the period of high occurrence, and the outbreaks cannot indicate the previous year’s temperature. Compared with floods, the relationship between droughts and locust plague was closer, and large-scale climate change may also affect locust outbreaks. (4) Long-term natural disasters multiplied the food price and food prices lagged behind disasters. Epidemics were often accompanied by locust plagues, forming a typical chain of agricultural disasters that did great harm to the society.

The design of europium(III)-based (Eu(III)-based) nanomaterials with good water dispersity and high fluorescence is of great importance for their bioapplication. In this work, Eu(III)-containing nanohydrogels were fabricated by a facile reflux-precipitation polymerization and their potential as theranostic nanomaterials were explored. The resultant PAAEu nanohydrogels (NGs) exhibited excellent monodispersity, high aqueous stability and strong fluorescence intensity. They could be internalized by cancer cells and showed high fluorescence signals after 5 hours of incubation. The in vitro cell assays confirmed the good cytocompatibility of PAAEu NGs with a cell viability of above 90% after 12 hours. After loading with the anticancer drug doxorubicin (Dox), Dox@PAAEu NGs induced cell apoptosis and necrosis and exhibited high cytotoxicity towards cancer cells. The prepared Eu(III)-containing nanohydrogels could be employed as theranostic nanomaterials for bioimaging and drug delivery applications.

The effect of hydrogen charging on microstructural evolution and corrosion behavior of a Ti-4Al-2V-1Mo-1Fe alloy in a 3.5 wt.% NaCl solution was investigated. The results showed that the hydrogen charging induced the formation and growth of γ-TiH and δ-TiH2 phases, leading to the initiation and propagation of hydrogen-induced cracks. It was also found that hydrogen charging can change the passivity of this alloy and increase its pitting corrosion susceptibility. The main reason for these was attributed to the formation of hydrides in α phase in the Ti-4Al-2V-1Mo-1Fe alloy, leading to the preferential dissolution of the α phase and thus the deterioration in the protective ability of passive film.

The friction and wear behaviors of a Fe-19Cr-15Mn-0.66N high nitrogen austenitic stainless steel (HNSS) were investigated. Tribological investigations were carried out under different applied loads of 5 N, 10 N, 15 N, and 20 N. Scanning electron microscope (SEM) and laser scanning confocal microscope (LSCM) were used to understand the wear mechanisms under different loads and the reasons for the improved wear resistance. The lower friction coefficient and improved wear resistance were observed with the increase in applied loads. Under a higher load, the friction enhanced the work hardening ability of HNSS, which in turn improved its surface hardness and thus the increased wear resistance of HNSS.

Neutral phosphine oxide ligands could coordinate with uranium in acidic radioactive liquid wastes with high affinity and selectivity. Limited success has been achieved in incorporating monodentate phosphine oxide sites into adsorbents to bind actinides due to the improper spatial distribution. Here, we present a deliberate design and construction of phosphine oxide host architectures which are structurally organized in the confined mesopores of MOFs for complexing uranium. By judicious selection of frameworks with an appropriate topology and mesoporous size, stable MOF-808 and NU-1000 were used to postsynthetically install phosphine oxide sites precisely and firmly via the ligand exchange of phosphonic acids. The material shows a high uranium adsorption capacity of 80 mg g−1 in 1 mol L−1 HNO3, with a high utilization of ligand sites and ultrafast sorption rate. XPS and DFT calculations reveal that the adjacent phosphine oxide sites could coordinate with UO22+ species simultaneously.

Mesoporous structure is important to promote mass transport and active site utilization of zeolites when used in reactions involving bulky molecules. However, their conventional hydrothermal synthesis is energy and labor intensive, requiring high-pressure operation, and lengthy heating a huge amount of alkaline liquid. We successfully synthesized new mesoporous zeolites, Meso-ZSM-5, via solid-state crystallization of dry aluminosilicate nanogels. Neighbor developing nanocrystals further joint at edges, creating connected, inter-lattice mesoscale pathway in the finished single crystalline zeolites. Palladium was further loaded on these zeolites to form a bi-functional catalyst (Pd/Meso-ZSM-5). When used in the hydrodeoxygenation (HDO) of guaiacol, a major bio-oil compound with disappointing conversion and severe coking issue over many HDO catalysts, Pd/Meso-ZSM-5 exhibits superior guaiacol conversion and product distribution when compared with those supported on conventional microporous ZSM-5 counterparts. This is attributed to the improved diffusion and accessibility of active sites inside Meso-ZSM-5 with its unique hierarchically porous structure. Ring saturated hydrocarbons are largely produced at 200 °C when hydrogenation dominates while alkaylated aromatics become major HDO products as deoxygenation becomes favorable at 250 °C. These encouraging results may ignite the wide use of these mesoporous zeolites in many other reactions in both traditional fossil fuel and emerging renewable energy fields.

The photocatalytic performance of TiO2 is severely restricted by its low photocatalytic activity and high charge-carrier recombination rate. In order to overcome these defects, a novel octahedral TiO2-MIL-101(Cr) (T-MCr) photocatalyst with type-II heterojunction and surface heterojunction is prepared by growth of TiO2 particles on MIL-101(Cr) via optimizing the synthesis conditions. The physicochemical, optical and photoelectrochemical properties of the samples are characterized utilizing several techniques, and its photocatalytic activity for liquid tetracycline and gaseous toluene degradation is evaluated under visible light irradiation. Particularly, the T-MCr-60 shows the outstanding photocatalytic activity. The improved photocatalytic performance of T-MCr-60 is ascribed to strong interfacial contact between (0 0 1) facets, (1 0 1) facets, and MIL-101 and the synergistic effects of two heterojunctions promoting efficient charge transfer. The possible photocatalytic mechanisms involving pollutants degradation pathway and charge transfer mechanisms during the process of pollutants degradation is also discussed.

Oral cancer is a multifactorial cancer that affects millions of peoples worldwide. The current exploration aimed to evaluate the mechanisms that thymoquinone nanoencapsulated carrier and its effects on 7,12-Dimethylbenz[a]anthracene (DMBA) stimulated hamster buccal pouch cancer in Syrian hamster model. Nanocarrier was characterized by SEM, TEM, FTIR analysis. The incidence of tumor, and biochemicals makers was studied through standard methods. The mRNA expression level of inflammatory markers NF-κBp50, NF-κBp65, and PI3K/AKT/mTOR markers in the buccal tissues of control and experimental animals were investigated through RT-PCR analysis. In thymoquinone (TQ) loaded calcium alginate and polyvinyl alcohol carrier (TQ/Ca-alg-PVA) no squamous cell carcinogenesis developed and others moderate dysplasia revealed differentiated form of hyperplasia and keratosis. In biochemical analyses with DMBA + TQ/Ca-alg-PVA (20 mg/kg bw) orally administered hamsters showed restored the antioxidants, detoxification, xenobiotic metabolising enzymes in DMBA induced plasma and oral tissues of hamsters. Further, mRNA expression level of NF-κBp50/p65 and PI3K/AKT/mTOR were upregulated in the DMBA alone painted hamster. In contrast, these expressions were down regulated in orally TQ/Ca-alg-PVA treated experimental animals. This ability more eligible to deregulate the inflammatory and PI3K/AKT/mTOR signaling pathway that proved it suppresses anti-invasion/metastasis activity during hamster buccal pouch carcinogenesis. From this study, we recommended that TQ/Ca-alg-PVA has documented as effective chemopreventive agents, in further many molecular machineries need to study.

Erythropoietin (EPO) has been regarded as a therapeutic glycoprotein for the clinical treatment of anaemia since its approval by the Food and Drug Administration (FDA) in 1989. Commercial production of the 165-residue glycoprotein is by recombinant protein expression using mammalian cell lines that renders a complex mixture of glycoforms that have an identical amino acid sequence but variations in the structures of the pendant glycans. This heterogeneous nature of human recombinant EPO restricts structural and bioactivity studies in medicinal chemistry. Consequently, chemical synthesis provides an elegant approach for the preparation of complex homogeneous glycoproteins from a readily accessible pool of amino acids and sugars. In addition, the combination of chemical and biosynthesis enables robust and large-scale production of homogeneous EPO. The scope of this minireview is to summarise the recent advances in the chemical and semisyntheses of homogeneous EPO glycoforms, highlighting the versatile approaches to the preparation and structural manipulations of the carbohydrate chains incorporated into synthetic EPO glycoproteins.

Nowadays, alkali metal-oxygen batteries such as Li-, Na-, and K-O2 batteries have been investigated extensively because of their ultrahigh energy density. However, the oxygen crossover of oxygen ba...

The uniform tablet-like TiO2/C nanocomposites with two crystal types (rutile and anatase) and large specific surface area (438 m2 g−1) were successfully prepared by Materials of Institut Lavoisier-125(Ti) (MIL-125(Ti)) calcined at a suitable temperature and applied for photocatalytic tetracycline (TC). The nanocomposites were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and mapping, N2 adsorption-desorption isotherms, photoluminescence spectra (PL), photocurrent, and X-ray photoelectron spectroscopy (XPS). The changes of physicochemical parameters are discussed in detail. It is found that nanocomposite through suitable calcination temperature (M-A-800) with large surface area and appropriate micropore/mesopore ratio could strengthen separation and migration rates of photo-generated charge, resulting in the improvement of visible light photocatalytic activity of tetracycline, and exhibited about 2.0 times quicker than that of MIL-125(Ti). In addition, M-A-800 displayed favourable reusability and stability in four circulation tests. Finally, the reaction mechanism of photocatalyst and photodegradation pathway of tetracycline was also proposed. O2− was the most important active species, and dehydroxylation and decarboxylation were the main photodegradation pathway of tetracycline.

The nano SiC coatings were prepared on the surface of graphite by laser irradiation under different laser energy densities (7.07–14.15 kJ/cm2). The influence of laser energy density on the structure and quality of coatings was systematically investigated. The results show that laser irradiation can transform the preset micron-SiC particle coating into nano-SiC particle coating. The nano-SiC coating prepared by laser irradiation can effectively enhance the high temperature oxidation resistance of the graphite substrate. When the laser energy density is 7.07 kJ/cm2, the prepared coating displays a single crystal structure and a good morphology without cracks and spheroidization. The coating prepared under the laser density of 10.61 kJ/cm2 shows a mixed crystal structure with obvious spheroidization. Further increase the laser energy density to 14.15 kJ/cm2, the main structure of prepared coating turns to polycrystalline and obvious cracks can be observed. The cross-section analysis of coating prepared under laser energy density of 7.07 kJ/cm2 indicates that there existed elemental diffusion between the coating and the substrate which increased the adhesion of coating. The calculations based on the Arrhenius formula present that this prepared coating has higher activation energy and therefore it has better high temperature oxidation resistance than the other prepared coatings.

Cu–Sn–Zn (CSZ) coatings are widely applied in communication devices due to their excellent performance in electrical/thermal conductivity, solderability, and corrosion resistance. Particularly, a novel TiO2–sol-enhanced electrodeposition method has been proposed to prepare CSZ–TiO2 nanocomposite coatings with different volume fractions of TiO2–sol. A series of CSZ–TiO2 nanocomposite coatings were prepared in the current study. The crystal phase, surface morphology, and micro- to nanostructures of sol-enhanced nanocomposite coatings were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Based on the prior research, we studied the microhardness, surface friction behavior, and corrosion behavior of the coatings. Our results indicate that adding 12.5 mL L−1 TiO2–sol increased the average microhardness of CSZ coating from 325 to 421 HV and reduced the corrosion rate by 42.8%. Those results reveal that the TiO2–sol affected the performance of CSZ coatings depends on the volume added. Additionally, we investigated the effects of TiO2–sol volume fraction on the morphology, microhardness, dry sliding wear-resistant capability, and corrosion-resistant capability.

Rechargeable magnesium ion batteries are potential candidates to replace the lithium ion batteries due to their high volumetric energy density, dendrite free cycling, and low costs. In present work, we have critically reviewed the recent advances made in the field of cathode materials development to achieve the high reversible capacities and working potentials. In first part, carbon-based cathodes such as fluorine-doped graphene nanosheets and graphite fluoride (CF0.8) are discussed in terms of compatibilities of positive electrode materials and electrolyte solutions for rechargeable magnesium-ion batteries. Whereas, the second part of this review focuses on crystal structure of vanadium oxide and its capability to accommodate the Mg2+ ions. Likewise, electrochemical performance of selected vanadium oxide based cathodes including VO2 (B), FeVO4.0.9H2O, Mo2.5+yVO9+δ, RFC/V2O5 and V2O5/Graphene composite, are discussed at different temperatures. To support the future research on magnesium ion batteries, particularly positive electrode material developments, several innovative research directions are proposed.

The vascular interventional surgery (VIS) is the most popular treatment for the cardiovascular and cerebrovascular diseases. Master-slave VIS robot is a promising technology to further improve the operation accuracy and surgical safety of both the patient and surgeon. The surgical outcome of robot assisted VIS highly depends on surgeon’s operating skills. However, current VIS robot systems affect the exerting of surgeon’s operating skills with different degrees due to the master manipulators with rigid-link structure or low detecting accuracy. To address this issue, a novel vascular interventional surgery robot based on surgeon’s operating skills is developed in this paper. A master manipulator is developed to contactlessly measure the surgeon’s operating motion. The surgeon operates the catheter with no limit, just as the operating manner in conventional VIS. It is enabled by measuring the catheter’s axial motion through tracking the edge of a series of markers with a macro camera, and by measuring the catheter’s rotational motion via a high-precise MEMS (Micro-Electro-Mechanic-System) gyroscope. Then, the developed master manipulator is integrated with a slave robot to construct the master-slave VIS robot system. Experimental results show that the detecting accuracy of the developed master manipulator are 0.71° and 0.104mm. Experimental results of surgical tasks implemented in EVE (endovascular evaluator) indicate that the developed robot system is superior to the system using a phantom as the master manipulator according to the metrics including operating time, path length, maximum speed and maximum accelerate.

Functionalized ionic liquid 1-cyanopropy-1-3-methylimidazoliumbis(trifluoromethanesulfonyl)imide (CPMIMTFSI) was synthesized as an electrolyte additive for high-voltage Li-ion batteries to improve the voltage resistance of carbonate-based electrolytes. The electrochemical behavior of LiNi0.5Mn1.5O4/Li cells was studied by charge–discharge testing, electrochemical impedance spectroscopy, and cyclic voltammetry. The surface morphology of LiNi0.5Mn1.5O4 cathodes was studied by scanning electron microscopy (SEM), and the results showed that when 15 vol% CPMIMTFSI was added to the ethylene carbonate (EC)/dimethyl carbonate (DMC) electrolyte, the highest discharge capacity of LiNi0.5Mn1.5O4/Li cells was 133.09 mAh g−1 at 0.2 C, which changed to 109.91 mAh g−1 at a high rate of 5 C. This value was 92.6% higher than that in EC/DMC electrolyte at 5 C. In addition, the discharge capacity retention rate of LiNi0.5Mn1.5O4/Li cell with 15 vol% CPMIMTFSI reached 95% after 50 cycles at 0.2 C, which was nearly 10% higher than that with EC/DMC electrolyte. The results of SEM and X-ray photoelectron spectroscopy showed that a uniform and dense electrolyte interface film was attached to the surface of LiNi0.5Mn1.5O4 cathode after adding CPMIMTFSI to the carbonate-based electrolyte.

The rechargeable magnesium ion batteries (MIBs) are ideal candidates to replace currently commercialized high energy density lithium ion batteries (LIBs) owing to their cost effective and environmentally friendly nature. However, bad performance of MIBs is a big challenge for researchers. In this review, we have critically discussed the state-of-the-art research activities made for the development of Mg-ion battery electrolytes and cathode materials with fast magnesiation kinetics. Emphasizing the chemical structures of both organic and inorganic electrolytes and their compatibilities with different cathode materials, the kinetic properties of electrochemical reactions for achieving optimized energy and power densities, are critically reviewed. To tackle the large polarizations of MIBs, the latest and emerging hybrid ion electrochemistries such as Mg–Li, Mg–Na, aqueous rechargeable Mg–Na, and Mg–Zn hybrid ion batteries, are highlighted to elaborate the merits and challenges of each electrolyte and nanostructured cathodes. The cathode materials covered in this review include various kinds of inorganic materials (i.e. metal oxides, metal sulfides), organic polymers, Prussian blue analogous and NASICON-type Li/Na cathodes with high working potentials. At the end, this review discuss comprehensive future research strategies for exploring new cathodes with high working voltages for MIBs.

The effects of heat treatment on the properties of electrodeposited Co–P–TiO2 nanocomposite coatings were systematically investigated. The TiO2 nanoparticles-reinforced Co–P–TiO2 nanocomposites wer...

Platinum–copper (PtCu) alloy nanostructures represent an emerging class of electrocatalysts for the methanol oxidation reaction (MOR) in direct methanol fuel cells (DMFCs), but practical applications have been limited by catalytic activity and durability. In this study, we developed an efficient one-pot hydrothermal strategy to prepare unique PtCu alloy nanorings (NRs) with a highly open hollow structure. The formation process of the hollow NR structure includes the initial formation of pure solid Cu nanocrystals (NCs), the subsequent galvanic replacement reaction between Cu and Pt2+, and the co-deposition of Pt and Cu atoms at the edges. The r-Pt0.75Cu/C catalyst, that is, Pt0.75Cu NRs with an input Pt/Cu molar ratio of 0.75/1 supported on carbon black exhibited superior MOR performance, with a mass activity of 2.175 A mgPt−1 and a specific activity of 52.26 A m−2, which are 4.5- and 6.6-fold enhancements relative to those of commercial PtRu/C-JM, respectively. Impressively, the durability of Pt0.75Cu NRs for the MOR can be enhanced dramatically by doping with trace Ir. The mass activity loss of r-Pt0.75Ir0.05Cu/C, that is, Ir-doped Pt0.75Cu NRs supported on carbon black, was only 7.44%, much smaller than those of r-Pt0.75Cu/C (37.76%) and PtRu/C-JM (50.27%) after 10 000 CV cycles. This work provides a strategic design of efficient PtCu catalysts for the MOR.

The lack of fundamental insights on the fate of micropollutants during conventional activated sludge treatment in wastewater treatment plants (WWTPs) presents one of the biggest challenges in optimizing their removal. To address this challenge, we designed a study to identify the drivers of micropollutant removal in WWTPs. We calculated the removal efficiency of micropollutants across the activated sludge process of full-scale wastewater treatment plants from literature-reported data. Our final dataset consisted of 529 independent observations for 84 micropollutants along with a set of associated activated sludge process parameters. We used the Eawag pathway prediction system to predict initial biotransformations for each of the 84 micropollutants and hierarchical clustering to group chemicals based on similarities in their predicted initial sets of biotransformations. We then applied stability selection to generate well-performing models that can be interpreted to uncover the key factors contributing to the range of removal efficiencies calculated for each cluster of micropollutants. The key factors considered in stability selection included six physicochemical properties of the micropollutants and six activated sludge process parameters. The sludge–water partitioning coefficient, molecular weight, solids retention time, influent micropollutant concentration, and dissolved oxygen levels were consistently identified as key factors of micropollutant removal for clusters of micropollutants that undergo certain types of initial biotransformations. Our findings highlight the importance of considering initial biotransformations when evaluating micropollutant removal and identify important process parameters that determine the fate of micropollutants during activated sludge treatment.

A highly sensitive and selective electrochemical sensor modified with poly-(L-cysteine)/CuO nanoneedles/N-doped reduced graphene oxide (L-Cys/NN-CuO/N-rGO) has been prepared for the testing of trace Pb2+. The electrochemical performance of this proposed sensor was investigated using electrochemical impedance spectroscopy (EIS). Based on the excellent electrochemical properties of NN-CuO/N-rGO as well as the specific complexation of natural substance L-cysteine with Pb2+, the L-Cys/NN-CuO/N-rGO was applied as a voltammetric biosensor for the determination of trace Pb2+ at pH 5.0. Under the optimum experimental conditions, the voltammetric peak current was linear with the Pb2+ concentration over the range from 0.001 to 5.0 nM and 5.0 to 1000 nM, respectively, with a low detection limit for Pb2+ concentration on the biosensor of 8.0 × 10−5 nM (S/N = 3). The significant sensitivity, selectivity, and electron conductivity of this L-Cys/NN-CuO/N-rGO modified electrode have also been studied. The specific detection of Pb2+ in water samples was also carried out.

Astrocyte maldevelopment is implicated in various neuropsychiatric diseases associated with early life stress. However, the underlying astrocytopathy mechanism, which can result in the psychiatric symptoms, remains unclear. In this study, it is shown that a reduced oligodendrocyte precursor cell (OPC) population accompanies hindered hippocampal astrocytic development in an improved parental isolation mouse model, and that the loss of OPCs suppresses astrocytic network formation and activity. It is further demonstrated that OPC‐derived Wnt ligands, in particular Wnt7b, are required for Wnt/β‐catenin pathway‐mediated astrocytic development and subsequent effects related to neuronal function. In addition, focal replenishment of Wnt7a/b is sufficient to rescue astrocytic maldevelopment. These results elucidate a Wnt‐paracrine‐dependent but myelin‐independent role of OPCs in regulating astrocytic development, which provides a unique insight into the astrocytopathy mechanism in early life stress, and can be implicated in the pathogenesis of human early life stress‐related neuropsychiatric disorders., Astrocyte maldevelopment, including defective astrocytic network formation, is implicated in neuropsychiatric diseases induced by early life stress. It is shown that reduced oligodendrocyte precursor cell (OPC) number occurred in early life stress causes astrocyte maldevelopment through decreased level of OPC‐derived Wnt ligands, which subsequently elicits neuronal dysfunction and neuropsychiatric symptoms.

A series of Co–P–TiO2 nanocomposite coatings were prepared via pulsed electrodeposition technique. TiO2 nanoparticles were embedded into the coating matrix using TiO2 sol. The phase constituents of...

This paper focuses on using the first curvature $\kappa(t)$ of trajectory to describe the stability of linear time-invariant system. We extend the results for two and three-dimensional systems [Y. Wang, H. Sun, Y. Song et al., arXiv:1808.00290] to $n$-dimensional systems. We prove that for a system $\dot{r}(t)=Ar(t)$, (i) if there exists a measurable set whose Lebesgue measure is greater than zero, such that for all initial values in this set, $\lim\limits_{t\to+\infty}\kappa(t)\neq0$ or $\lim\limits_{t\to+\infty}\kappa(t)$ does not exist, then the zero solution of the system is stable; (ii) if the matrix $A$ is invertible, and there exists a measurable set whose Lebesgue measure is greater than zero, such that for all initial values in this set, $\lim\limits_{t\to+\infty}\kappa(t)=+\infty$, then the zero solution of the system is asymptotically stable.

Chromium coatings are largely restricted in electrical and electronic industries due to the environmental concerns. To address these concerns, a cobalt–phosphorus–titanium oxide (Co–P–TiO2) nanocomposite coating is developed in this study using a nanoparticle-reinforced electrodeposition process. The effects of TiO2 nanoparticles on the properties of co-deposited Co–P–TiO2 nanocomposite coatings are investigated. The surface characterisation is carried out by scanning electron microscopy and atomic force microscopy, while the crystal structure is studied using X-ray diffraction. The mechanical properties of nanocomposite coatings including microhardness and wear resistance are also determined. To study the electrochemical behaviour of the coatings, the potentiodynamic polarisation analysis combined with electrochemical impedance spectroscopy is performed. The Co–P–TiO2 coating at 1 g/L TiO2 addition displays the best physicochemical performance. Compared to Co–P coating, the mechanical properties of the nanocomposite coating are significantly improved by the strengthening effects of the well-dispersed TiO2 particles. Excellent corrosion resistance is also achieved for the Co–P–TiO2 at proper TiO2 addition due to its smooth and defect-free microstructure. However, it is found that the excessive addition of TiO2 decreases the coating quality, resulting in an unfavourable microstructure and properties.

For increasing the interfacial bonding of Ni deposits onto Ti surface, the objectives of this work are to explore an effective approach for LaCl3-modified Ni nanocrystals on porous surface of Ti substrate. Three-dimensional (3D) heterotypic nanopores were well organized with a diameter size of ~300 nm through surface anodizing in H3PO4-containing acid solution at DC 180 V. In view of the above considerations, the anodized surface with a 3D-open reticular structure was processed of high adsorption capacity leading into pitting growth of Ni crystals into 3D-pores. Experimental data have referred that a leaf-like surface with the diversified orientations of Ni (111) (200) (220) (311) facets were conducted for Ni-LaCl3 deposits instead of an exclusive growth of Ni (111) (200) facets for pure Ni. Based on Nanoindentation tests, it exhibited the ratio of micro hardness (H3) and elastic modulus (E2) of Ni samples remarkably increased with increasing LaCl3 addition from 0 to 2.0 g/L. As excepted, the steady-state friction coefficient was ~0.28 for Ni-2.0 g/L LaCl3 composites, which was about one order of magnitude lower than that of pure Ni sample during oxidized at 500 °C in air. The exceptional improvements of corrosion resistance for LaCl3-modified Ni deposits were associated with the co-existence of high adsorptive La3+ ions and the La-rich insoluble corrosive products in 1 M (mol/L) HCl solution. In light of this, Ni-based nanocomposites on 3D-heterotypic porous surface of Ti alloys would provide an effective guidance for protecting Ti alloys against wear and corrosive damages.

In this study, Ni–P, Ni–W–P and Ni–B coatings were electrolessly plated on aluminium alloy substrates. All coatings were uniform and adherent with shiny metallic appearances. A systematic study was...

The abundance of natural gas and biomass in the U.S. was the motivation to investigate the effect of adding methane to catalytic nonoxidative high-temperature biomass gasification. The catalyst use...

We report a class of pKa-directed, precise incorporation of phosphonate ligands into a zirconium-based metal–organic framework (Zr-MOF), MOF-808, via ligand exchange. By replacing of formate ligand...

Here, we prepared nano-SiO2-coated graphite films using a novel laser-assisted sol–gel method. The SiO2 sol–gel prepositioned on the graphite substrate was irradiated by the fiber laser at different energy densities. The growth mechanism of the coatings under laser irradiation was studied and the effects of processing parameters on the coating structure were systematically investigated. In addition, the high-temperature oxidation resistance of these samples was examined. Surface morphology and elemental composition were examined using scanning electron microscopy and energy-dispersive spectrometer. Phase constituents and microstructure were identified by x-ray diffraction and transmission electron microscopy. The oxidation resistance was analyzed by thermal gravimetric analysis. The results found that laser irradiation significantly modifies the sol–gel-deposited nano-SiO2 layer. A uniform and compact nano-SiO2 coating was obtained when irradiated by laser energy density of 14.4 kJ/cm2. Optimum high-temperature oxidation resistance was achieved for the two-layer SiO2-coated films.

We report in this paper a simple method of coating very thin graphene film on titanium substrate, affording it markedly enhanced resistance to corrosion and much decreased electrical contact resistance under the environment of proton exchange membrane fuel cells (PEMFC). The graphene film is formed by electrodepositing graphene oxide (GO) on Ti sheet via normal pulse voltammetry, followed by reducing the deposited GO at 500 °C in hydrogen atmosphere. The resultant graphene film, with a thickness of only around 50 nm, evenly covers and covalently bonds to the Ti sheet, as revealed by SEM, Raman and XPS. Both potentiodynamic and potentiostatic tests of the graphene coated Ti (G/Ti) sample are conducted under simulated chemical environment and electrode potentials of PEMFC. Under all the circumstances, the corrosion currents of G/Ti sheet are in the order of 10−7 A/cm2, significantly less than that of bare Ti sheet. Moreover, the coated graphene film on Ti sheet leads to a much lower and more stable interfacial contact resistance (ICR) of around 4 mΩ cm2. These results mean that the G/Ti sheet meets the U.S. DOE target of 2020 for PEMFC bipolar plates (BP) in terms of both the corrosion and electrical resistance. Therefore, the G/Ti sheet appears to be a very promising BP material in PEMFC.

The past decade has witnessed the great promise of strategies for ligand discovery based on surface-immobilized GPCRs. We present here a method for preparation of immobilized GPCRs. Key features include covalent immobilization with high specificity and robust application in drug-receptor interaction analysis and ligand screening. In our example assay using beta2-adrenergic receptor (β2-AR), the human DNA repair protein O6-alkylguanine-DNA alkyltransferase (hAGT) fusion receptor expressed in Escherichia coli was directly captured onto polyethylene glycol polyacrylamide (PEGA) resin. We observed even distribution and physiological functions of β2-AR on the resin. The immobilized β2-AR as a stationary phase enabled us to rapidly determine the binding of four drugs to β2-AR. By coupling this assay to mass spectrometry, we screened rosmarinic acid as a bioactive compound targeting β2-AR in Fructus Perillae. We concluded that O6-benzylguanine derivative-functionalized supporter is promising for specific immobilization of hAGT-tagged proteins; immobilized receptor chromatography has great potential in screening receptor-binding leads from herbal plants or traditional medicine recipes.

Diet has been regarded as the main exposure source of perfluoroalkyl acids (PFAAs), but the national dietary survey of PFAAs in China was limited. Here, eight typical PFAAs were detected in milk, aquatic food, meat, and eggs from the Chinese Total Diet Studies (TDSs) during 2005–2007 and 2011–2013. Aquatic food was found to be the main source of PFAAs among animal-origin foods. The estimated dietary intakes of ∑PFAAs from animal foods (EDIanimal-origin foods) in coastal areas were relatively higher than in inland areas. The highest EDIanimal-origin foods of PFOS [4.07 and 2.02 ng kg–1 of body weight (bw) day–1] and PFOA (2.19 ng kg–1 of bw day–1) found in Shanghai and perfluorononanoic acid (PFNA, 2.72 ng kg–1 of bw day–1) in Fujian approach or exceed current minimal risk levels from the Agency for Toxic Substances and Disease Registry and tolerable weekly intakes from the European Food Safety Authority, suggesting potential risk of PFAA exposure from animal-origin foods in these areas.

Assays of uric acid (UA) in human urine and blood are of great significance to clinic diagnoses of many diseases, such as gout, renal failure, and hyperuricemia. Portable and visual quantification method, however, has been rarely developed for POCT detection of UA in urine and blood samples. In this work, we developed the electrophoresis titration (ET) model, the relevant sensing method and the portable chip device for portable and visual detection of UA in both urine and blood based on moving reaction boundary (MRB). In the model, uricase catalyzes UA in the anode well to allantoin, producing hydrogen peroxide, which oxidizes leucocrystal violet dye without charge to crystal violet (CV+) with one positive charge. Under an electric field, a MRB was created between the violet CV+ moving from the anode well into the channel and the alkaline sodium acetate in channel, resulting in an ET sensing. The model indicated that the distance of MRB under given conditions was as a function of UA content, implying an extraordinary simple sensing for UA. Based on the MRB-ET model, a series of experiments were conducted. The results evidently validated the model and method of ET-MRB. The experiments not only demonstrated the high facility and portability of MRB-ET model, but also showed the visuality, selectivity and rapidity. In addition, the experiments revealed the fair sensitivity (

Polymer-based gate dielectrics have received growing attention due to their important role in field-effect transistors (OFETs). This review article aims to present the recent progress of polymer dielectrics for high-performance OFET applications. We first discuss the requirements for polymer dielectrics in tailoring the overall performance of OFETs from the perspective of both bulk material properties and surface characteristics of the polymers. On this basis, we introduce the design strategies and desired processing techniques of polymer dielectrics for optimizing the charge transport and stabilizing the operation of OFETs. Then, we highlight the recent advances in polymer-based dielectrics by classifying and comparing different categories of polymeric materials as well as polymer nanocomposites, and focus is also given to elucidating the critical relationships between polymer structures, gate dielectric properties and OFET performance. Finally, a perspective of future research directions and challenges ...

We demonstrated the mode structure of a folded telescopic structural resonator used in high energy laser. The scalar diffraction theory and iterative algorithm are applied to simulate the effect of intracavity phase disturbation on eigenmode features of the telescope structural unstable resonator. The transverse-mode properties and beam quality have been investigated experimentally with H S wavefront analysis and Zernike aberration function by including resonator misalignment parameters. Starting from a comparative analysis of the first 64-order Zernike coefficient of the wavefront, it is shown that typical low order perturbation notablely affects the eigenmode intensity, and will also increases the relevant high-order aberrations such as A3, A5 and A7 in wavefront features. High order frequency Zernike aberration of beam will obviously degrade outcoupled beam properties, e.g., the base transverse mode will turn into the multi-mode. The beam quality can be effectively improved by the priority correction of low order intracavity Zernike aberration in such structural resonators.

The influence of the degree of hydrolysis (DH) on the structure, solubility and emulsifying properties of rice bran protein (RBP) was investigated. Sodium dodecyl sulfide polyacrylamide gel electrophoresis (SDS-PAGE), intrinsic fluorescence, surface hydrophobicity and circular dichroism (CD) techniques were used for the analysis of the structural characteristics. Hydrolysis can change the molecular weight of the protein, increase its flexibility and fluidity, change its surface hydrophobicity, and increase its solubility. Oil-in-water emulsions were prepared from rice bran protein hydrolysates (RBPH) with different DH values (1%, 3%, and 6%). The stabilities of the RBPH-stabilized emulsions were investigated under the following environmental pressures: pH (3–9), ionic strength (0–300 mM NaCl) and thermal treatment (30–90 °C, 30 min). Particle size and surface charge (ζ-potential) were measured as an indication of the emulsion stability. Emulsions prepared with 3% DH RBP were much more stable than the emulsions prepared with RBPH with other DH values, and this RBP has potential as an emulsifier in the food industry.

A zeolitic imidazolate framework-8 (ZIF-8)/reduced graphene oxide (rGO) nanocomposite was formed by using an efficient synthetic method. The morphology and structure of the ZIF-8/rGO nanocomposite were characterized by scanning electron spectroscopy (SEM), X-ray diffraction (XRD) and thermogravimetric analysis (TGA) mapping. The ZIF-8/rGO nanocomposites were immobilized on a carbon paste electrode (CPE) to construct a high-performance nonenzymatic electrochemical H2O2 sensor. A cyclic voltammetry (CV) study showed that the ZIF-8/rGO nanocomposites displayed better electrocatalytic activity toward H2O2 reduction compared to that of ZIF-8. An amperometric study indicated that the H2O2 sensor displayed high performance, which offered a low detection limit (0.05 μM) (S/N = 3), a high sensitivity (4.01 μA mM−1 cm−2), and a wide linear range (from 1.0 to 625 μM). An electrochemical reaction mechanism was proposed for H2O2 reduction on the ZIF-8/rGO/CPE. Importantly, the as-fabricated H2O2 sensor exhibited good reproducibility and excellent selectivity. Furthermore, the constructed high-performance sensor was utilized to monitor the H2O2 levels in real samples, and satisfactory results were obtained. These results demonstrated that the ZIF-8/rGO nanocomposite can be used as a good electrochemical sensor material in practical applications.

Near-infrared (NIR) imaging with indocyanine green (ICG) has been proven to be feasible for the visualization of tumor and enables real-time guidance during tumor resection. However, ICG is a non-receptor-specific NIR dye that also accumulates in other hyperpermeable tissues such as inflammatory tissues. In this study, we found visible differences between tumor and inflammation in 6 oral cancer patients by obtaining NIR images after 24 hours of 0.75 mg kg−1 ICG injection. In order to obtain the optimal ICG dose and observation time for better discrimination effect, we constructed the sponge implant model of angiogenesis and subcutaneous tumor model in the same C3H mice for further study. This mouse model was the first to prove the feasibility of ICG-NIR imaging and the difference between tumor and inflammation was successfully acquired in the model. Studies on this model avoid the interference of individual differences between tumor and inflammation and revealed the causal relationship between tissue permeability and fluorescence. The difference between the ICG kinetics of the tumor and inflammatory tissues was studied based on this mouse model. Results showed that the tumor-to-inflammation ratio (TIR) of fluorescence intensity was dose independent and increased with time, indicating that more ICG leakage and less clearance in tumors may lead to brighter NIR imaging than in inflammations. Thus, we recommend a high ICG injection dose and long observation time in order to better differentiate between tumor and inflammation by NIR imaging.

(1) Background: The health effect of temperature has become a rising public health topic. The objective of this study is to assess the association between apparent temperature and non-accidental deaths, and the mortality burden attributed to cold and heat temperature; (2) Methods: The daily data on temperature and deaths were collected from 10 cities in Thailand, Korea and China. We fitted a time-series regression with a distributed lag nonlinear model (DLNM) to derive the health risk of temperature for each city and then pooled them to get the overall cumulative risk by multivariate meta-analysis. Additionally, we calculated the attributable fraction of deaths for heat and cold, which was defined as temperatures above and below minimum-mortality temperature (MMT); (3) Results: There are regional heterogeneities in the minimum mortality percentiles (MMP) and attributable fractions for different countries. The MMP varied from about the 5–10th percentile in Thailand to 63–93rd percentile in China and Korea. The attributable fractions of the total deaths due to short-term exposure to temperature in Asia is 7.62%, of which the cold effect (6.44%) is much higher than the heat effect (1.18%); (4) Conclusions: Our study suggested that apparent temperature was associated with an increase in non-accidental mortality. Most of the temperature-related mortality burden was attributable to cold, except for Thailand.

To retard the spread of fire in many cases with sealing materials is significant. A series of silicone rubber foam materials were prepared with room temperature vulcanization and foaming reactions. The morphology, chemical structure, cell structure, and thermal stability were investigated and results proved that the synthesis of silicone rubber was successful in a wide range of feed ratios. The fire-retardant tests were carried out to study the fire-proof property of the composite materials, and the excellent performance showed a promising prospect for wide application in sealing materials.

To utilize its rich aromatics, lignin, a high-volume waste and environmental hazard, was depolymerized in supercritical ethanol over various zeolites types with different acidity and pore structures. Targeting at high yield/selectivity of aromatics such as phenols, microporous Beta, Y, and ZSM-5 zeolites were first examined in lignin ethanolysis, followed by zeolites with similar micropore size but different acidity. Further comparisons were made between zeolites with fin-like and worm-like mesoporous structures and their microporous counterparts. Despite depolymerization complexity and diversified ethanolysis products, strong acidity was found effective to cleave both C–O–C and C–C linkages of lignin while mild acidity works mainly in ether bond breakdown. However, when diffusion of gigantic molecules is severe, pore size, particularly mesopores, becomes more decisive on phenol selectivity. These findings provide important guidelines on future selection and design of zeolites with appropriate acidity and pore structure to promote lignin ethanolysis or other hydrocarbon cracking processes.

In this study, 16S rRNA high-throughput sequencing technology was used to analyze the composition and diversity of bacterial and fungal communities in mushroom residue samples at different composting stages. During the composting process, the maximum temperature in the center of the pile can reach 52.4°C, and the temperature above 50°C has been maintained for about 8 days. The results showed that Actinobacteria, Firmicutes, Proteobacteria, Bacteroidetes, and Chloroflexi were the main microorganisms in the composting process, accounting for 98.9%-99.7% of the total bacteria. Furthermore, in order to obtain the protein expressed in each stage of composting, the nonstandard quantitative method (label free) was used to analyze it quantitatively by mass spectrometry, anda total of 22815 proteins were identified. It indicated that the number of identified proteins related to cellulose decomposition and the number of differentially expressed proteins were significantly enriched, and the functional proteins related to cellulose decomposition had significant stage correspondence.