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The objective of this study was to investigate the effects of co-exposure of iron and microplastics (MPs) on the cognitive function of aged humans and animals. It was already known that individual iron or MPs exposure can initiate potential neurotoxicity. However, the combined effect of MPs and iron remained to be elucidated. In this study, the toxicity of iron, MPs, co-treatment of MPsiron, and the underlying mechanisms were evaluated in vivo. Our findings suggest that 5 µm MPs could enter the aging mice brain and accumulate in cortex and hippocampus. In addition, MPs and iron have a good binding ability, therefore, co-exposure of MPsiron cause significant iron overload and cognitive deficits as compared to control and individual treatments of iron and MPs. Moreover, the lipid peroxidation and inflammation, which are involved in ferroptosis, get significantly elevated by co-exposure of iron and MPs. Taken together, our results provide compelling evidence that co-exposure of iron and MPs could aggravate the cognitive impairment via disturbing brain iron homeostasis and inducing ferroptosis in cognitive-related brain areas, what's more, the results warn that MPs may act as vectors of pollutants (mostly heavy metals) increasing the health burden on body.

Moisture is a significant factor that affects the insulation performance of outdoor high-voltage insulators in power systems. Accumulation of water droplets on insulators causes severe problems such as flashover of insulators and power outage. In this study, we develop a method to fabricate a micro/nano hierarchical super hydrophobic surface. The as-prepared super hydrophobic surface exhibits a water contact angle (WCA) of 160.4 ± 2°, slide angle (SA) less than 1° and surface free energy (SFE) of 5.99 mJ/m 2 . We investigated the electrohydropdynamic behavior of water droplet on a horizontal super hydrophobic surface compared with hydrophobic RTV silicone rubber surface which was widely used as anti-pollution coating or shed material of composite insulator. Results show that water droplet tended to a self-propelled motion on the super hydrophobic surface while it tended to elongate and break up on the RTV surface. The micro/nano hierarchical surface structure and chemical components with low surface free energy of the super hydrophobic surface jointly contributed to the reduction of skin fraction drag and subsequently made it possible for the motion of water droplet driven by electric field. Furthermore, the self-propelled motion of water droplets could also sweep away contaminations along its moving trace, which provides super hydrophobic surface a promising anti-pollution prospect in power systems.

In this work, boron and nitrogen co-doped hierarchical porous carbon (BN-HPC) with a relatively high contents of boron (3.97 wt%) and nitrogen (12.10 wt%) is synthesized by a method combined with template process and carbonization of hierarchical porous resin using melamine and boric acid as nitrogen and boron sources, respectively. The co-doping method achieves a high boron doping level (8 times of that of single boron doped sample) which is of great significance in increasing the doping efficiency of boron. The hierarchical porosity, structure and surface chemical properties are studied in detail via various means, such as Transmission Electron Microscopy, N 2 sorption, X-ray diffraction, X-ray photoelectron spectroscopy and elemental analysis, etc. Owing to the synergistic effect of hierarchical porosity and heteroatoms doping, BN-HPC exhibits greatly improved electrochemical capacitive performance of 304 F g −1 at a current density of 0.1 A g −1 and good rate capability (189 F g −1 remained at a current density of 10 A g −1 ). The strategy of synthesis is facile and very effective.

Super-hydrophobic coatings have recently drawn considerable attention in research and applications towards self-cleaning materials. This paper presents experiments and analysis of water droplet behaviors on glass, silicone rubber, and super-hydrophobic surface in an ac electric field applied parallel to the surface. Experimental results show that a water droplet tends to move on a super-hydrophobic surface while it tends to stretch or deform on glass and silicone rubber surfaces. A physical model of the water droplet deformation and motion mechanism is presented. An electrostatic force acting as the domain driving force plays a key role in water droplet motion on super-hydrophobic surface. The electrostatic stress acting along the external profile of a water droplet cross section was simulated using a surface integral of the Maxwell stress tensor. The simulation for surfaces with different wetting properties are in good agreement with the experimental results. Super-hydrophobic coating demonstrates a prospective electric field enhanced self-cleaning property.

Icing on insulators affects seriously the operation safety of high voltage transmission lines. Super-hydrophobic and semi-conducting coatings show anti-icing potential for insulators on transmission lines. By combining super-hydrophobicity and electrothermal effects, a hydroxy-terminated polydimethylsiloxane (OH-PDMS)-modified nano-silica/carbon hybrid coating was developed to solve the problem of insulator icing. The anti-icing performance of insulators coated with OH-PDMS-modified nanosilica/ carbon hybrid coating were investigated. Leakage current, temperature distribution, ice morphology, icicle length, and flashover voltage of the insulators are presented. Both the electric and the thermal field distributions were analyzed to verify anti-icing performance of the coating. Experimental results show that the joule heat generated by the coating increases the insulator surface temperature, and the OHPDMS- modified nano-silica/carbon hybrid coating has a superior performance to super-hydrophobic coating in terms of reducing ice accretion and improving flashover voltage of insulators.

Super-hydrophobic coatings have recently drawn a lot of attention in research and applications towards reduction of ice accumulation on insulators. This paper presents a new type of hybrid coating fabricated via self-assembly of a super-hydrophobic layer on a semi-conducting layer. Hydroxy-terminated polydimethylsiloxane (OH-PDMS) modified nano-silica is used for fabrication of the super-hydrophobic layer. Fabrication procedures, hydrophobic characteristics, and flashover performances of the hybrid coating are presented. Experimental results show that the hybrid coating has a dual micro- and nano-scale hierarchical structure and a water contact angle greater than 155°. Surface resistivity, volume resistivity, temperature rise, and surface flashover voltages of the hybrid coating are also presented. Temperature distribution on the hybrid coating is simulated for further analysis. The results show that the hybrid coating is capable of improving the electrical field and surface temperature along the surface of the coating.

Improving the electrochemical performance of manganese dioxide (MnO 2 ) electrodes is of great significance for supercapacitors. In this study, a novel honeycomb MnO 2 nanospheres/carbon nanoparticles/graphene composites has been fabricated through freeze-drying method. The honeycomb MnO 2 nanospheres are well inserted and dispersed on the graphene. Carbon nanoparticles in the composites act as spacers to effectively prevent graphene from restacking and agglomeration, construct efficient 3D conducting architecture with graphene for honeycomb MnO 2 nanospheres, and alleviate the aggregation of honeycomb MnO 2 nanospheres by separating them from each other. As a result, such honeycomb MnO 2 nanospheres/carbon nanoparticles/graphene composites display much improved electrochemical capacitive performance of 255 F g −1 at a current density of 0.5 A g −1 , outstanding rate capability (150 F g −1 remained at a current density of 20 A g −1 ) and good cycling stability (83% of the initial capacitance retained after 1000 charge/discharge cycles). The strategy for the synthesis of these composites is very effective.

Super-hydrophobic surfaces can be fabricated based on discarded silicone after arc exposure. Hydrophobicity, microstructural development, chemical composition, corrosive liquid resistance, and the microscopic process of contaminant elimination of the surface are presented. High temperature of the arc discharge plays a substantial role in the preservation of surface hydrophobicity.

Ice accumulation on transmission lines, caused by freezing rain, wet snow or frost, is one of major problems influencing safety of electric power system. Super hydrophobic coating on insulators is a kind of efficient way to solve the problem. Many kinds of super hydrophobic coatings are widely used in power system, especially fluororesin based coating which is cheap and has good outdoor weathering capabilities. However, after arc burning, fluororesin based super-hydrophobic coating would be destroyed due to partial temperature rising. Addition of high thermal conductive nanoparticles can increase thermal conductivity of coating and improve its arc resistant ability compared with undoped coating. In this paper, heat conductivity behaviors of super hydrophobic with BN particles is studied. The charge polarity, charging time and charging voltage also play an important role on arc electric erosion behaviors. Samples were prepared by dispersing BN nanoparticle into coating. DC arc test was performed using inclined plane test method.

The paper aims at studying the electrical driven rolling behavior of water droplet on a super-hydrophobic surface under electrical field. Firstly, Parallel plate electrodes and super-hydrophobic surface (contact angle > 150°) are adopted. Experiments are conducted to investigate deformation and rolling behavior of water droplet on super-hydrophobic surface when A.C voltage is applied. Secondly, Electrical field distribution of water droplet on super-hydrophobic surface is simulated with Finite Element Method (FEM). Electrostatic stress that drives water droplet to roll is calculated by combing electrical field distribution results with Maxwell stress tensor. Simulation and calculation results indicated electrostatic force had a tendency to drive water droplet to roll.

In high soil resistivity regions, values of grounding resistance of substations are usually difficult to meet the requirements of working earthing and safety earthing. The common methods for reducing the grounding resistance are not practical. In order to solve this problem, a steel fiber/graphite conductive concrete is developed in this paper. Steel fiber and graphite are added as conductive fillers. Orthogonal experimental design is applied to formulation optimization. The resistivity, compressive strength and flexural strength of steel fiber/graphite conductive concrete are measured for obtaining the optimal formula. The results demonstrate that the steel fiber/graphite conductive concrete not only has the advantage of small resistivity, but also has excellent mechanical property and good material dispersion effect.

The icing flashover is increasingly becoming a serious problem with the development of the extra-high voltage engineering. Reducing the bonding strength between the substrate and the ice by super-hydrophobic coating is a choice for the anti-icing. The bare insulator, RTV coated insulator and the super-hydrophobic insulator are chosen for comparing. The experimental facility is set up. The vertical bonding strength, the vertical fracture energy, the shear bonding strength and the shear fracture energy are detected after first ice glaciations and second one. Results show that bonding strength between the super-hydrophobic substrate and the ice is less than that of the RTV coated insulator and the ice. The deiced surface still shows good super-hydrophobicity and the small ice bonding strength keeps almost the same which show good prospect for the anti-icing and de-icing.

Ice accretion on high voltage overhead transmission lines is a serious problem for power system and there's no satisfactory solution to solve icing problem at present. Ordinary glass insulators can obtain super-hydrophobic and self-cleaning properties by coating super-hydrophobic coating on surfaces. The current research shows that super-hydrophobic coating has potential to fix icing problem, because of its excellent hydrophobicity. In this paper, key point is focused on de-iced super-hydrophobic coating's hydrophobicity and surface micro-structure for verifying super-hydrophobic coating's long-term efficacy. Related experiments were completed, and room temperature vulcanized silicone rubber (RTV) coating and blank sample were used as reference samples. The experiments' results showed that de-iced super-hydrophobic coating's static contact angle still reached 158° and its surface still maintained its binary micro-nano coarse structure, and there were no signs of damage on its surface. These phenomena indicate that super-hydrophobic coating's surface micro-structure has outstanding mechanical strength, which can resist the negative impact of de-icing process and keep its outstanding hydrophobicity. Therefore, super-hydrophobic coating has long-term stability under freeze-thaw cycles.

In this Letter, the dewetting behavior of superhydrophobic condensing surfaces under a tangential AC electric field is reported. The surface coverage of condensed droplets only exhibits a negligible increase with time. The jumping frequency of droplets is enhanced. The AC electric field motivates the dynamic transition of droplets from stretch to recoil, resulting in the counterforce propelling droplet jumping. The considerable horizontal component of jumping velocity facilitates droplet departure from superhydrophobic surfaces. Both the amplitude and frequency of AC voltage are important factors for droplet departure and dewetting effect. Thereby, the tangential electric field provides a unique and easily implementable approach to enhance droplet removal from superhydrophobic condensing surfaces.

The insulators coated with super-hydrophobic coating have good performance of anti-icing. But the super-hydrophobic coating can't completely preventing ice accumulation, especially the soft rime. In order to solve this problem, a kind of semiconductor coating was prepared in this paper,and then the super-hydrophobic coating was structured on the semiconductor film,and the basic property of this kind of composite anti-ice coating was tested. The results show that the semiconductor film have good insulation performance,the temperature of semiconductor film can be raised 3∼6°C under high voltage and the water contact of the super-hydrophobic coating surface can reach to 155°. The combination of the super-hydrophobicity of the super-hydrophobic coating and the electric heating property of the semiconductor film are expected to solve the anti-icing problem of the insulators on the transmission line completely.

Small ice adhesion surface is always desirable for high voltage overhead transmission line, which is favorable for ice shedding with very small external force acting. This paper studies the tensile strength and the shear strength respectively of ice on the surface of PDMS/nano-silica hybrid super-hydrophobic coating, which keeps average water contact angle (CA) larger than 150° and water slidding angle (SA) smaller than 5#x00B0;. Compared with bare glass surface and the surface coated with Room Temperature Vulcanization Silicone (RTV), the PDMS/nano-silica hybrid super-hydrophobic surface did decrease ice adhesion strength obviously, its tensile ice adhesion strength is 325.5 times and 27.7 times lower than the bare samples and the surface coated with RTV respectively, and its shear ice adhesion strength is even 2149 times and 139.6 times lower than the bare samples and the surface coated with RTV respectively.

In this letter, we report a fast, simple, and single step approach to the preparation of transparent super-hydrophobic coatings on a copper conductor via atmosphere pressure arc discharges. The preparation procedures, hydrophobic characteristics, anti-pollution capability, and transparency of the super-hydrophobic coating are presented. A dual micro- and nano-scale hierarchical structure is observed on the super-hydrophobic coating with a water contact angle greater than 150°. The coating is, thus, capable of removing a significant amount of contaminants with a small quantity of water droplets. Attenuated total reflection Fourier transform infrared spectroscopy indicates that hydrophobic methyl groups exist on the surface of the coating. The surface roughness measurement results prove that the super-hydrophobic surface obeys the Cassie-Baxter model and its light scattering is very weak. Results demonstrate the conceptual feasibility of production of optically transparent super-hydrophobic coating by arc spraying of polymers under the atmospheric pressure.