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Ultra-high voltage (UHV) transmission lines are important for electricity transmission. Medium phase bridge shape cross bear is a special structure; No tool can be used to replace the V-hanging insulator string with live power. In view of this problem, the live overhaul method of V-hanging insulator string of medium phase bridge shape cross bear in 500kV transmission line is invented, the security is analyzed, and the developed equipment is simulated and tested. The results of the research show that it can meet working conditions and accelerate working efficiency, which is important for the kind of maintenance.

Multi-dimensional nanomaterials possess a porous structure and plenty of active sites, so they have promising prospects in supercapacitor applications. As the typical pseudocapacitance materials, interlaced CoS nanoflakes and two-dimensional NiO nanosheets were assembled into multi-dimensional CoS/NiO architectures. The fabricated CoS/NiO nanostructures on nickel foam can directly serve as the supercapacitor electrodes. Such multi-dimensional CoS/NiO architectures exhibit the enhanced electrochemical performances in the light of the cyclic voltammetry curves and galvanostatic charging-discharging (GCD) tests. A multi-dimensional CoS/NiO electrode releases a high specific capacitance of 1620 F g-1 at 1.0 A g-1, which is distinctly higher than those of pristine CoS and NiO electrodes. The CoS/NiO//nitrogen-doped carbon nanoarrays (NC) asymmetric supercapacitor (ASC) can operate stably at 1.6 V. The GCD curves of the ASC at diverse current densities within the voltage window of 0-1.6 V exhibit reasonable symmetry. The CoS/NiO//NC ASC shows great long-term cycling performance, it has 93.5% capacity retention after 3000 cycles. Electrochemical analyses and detailed material characterizations are performed to reveal the mechanism for the enhanced performance of capacitance.

It has been observed that microfluidic chips used for synthesizing (18)F-labeled compounds demonstrate visible light emission without nearby scintillators or fluorescent materials. The origin of the light was investigated and found to be consistent with the emission characteristics from Cerenkov radiation. Since (18)F decays through the emission of high-energy positrons, the energy threshold for beta particles, i.e. electrons or positrons, to generate Cerenkov radiation was calculated for water and polydimethylsiloxane (PDMS), the most commonly used polymer-based material for microfluidic chips. Beta particles emitted from (18)F have a continuous energy spectrum, with a maximum energy that exceeds this energy threshold for both water and PDMS. In addition, the spectral characteristics of the emitted light from (18)F in distilled water were also measured, yielding a broad distribution from 300 nm to 700 nm, with higher intensity at shorter wavelengths. A photograph of the (18)F solution showed a bluish-white light emitted from the solution, further suggesting Cerenkov radiation. In this study, the feasibility of using this Cerenkov light emission as a method for quantitative measurements of the radioactivity within the microfluidic chip in situ was evaluated. A detector previously developed for imaging microfluidic platforms was used. The detector consisted of a charge-coupled device (CCD) optically coupled to a lens. The system spatial resolution, minimum detectable activity and dynamic range were evaluated. In addition, the calibration of a Cerenkov signal versus activity concentration in the microfluidic chip was determined. This novel method of Cerenkov radiation measurements will provide researchers with a simple yet robust quantitative imaging tool for microfluidic applications utilizing beta particles.

Controlling the size distribution of polymer-based nanoparticles is a challenging task due to their flexible core and surface structures. To accomplish such as task requires very precise control at the molecular level. Here we demonstrate a new approach whereby uniform-sized supramolecular nanoparticles (SNPs) can be reliably generated using a digital microfluidic droplet generator (DMDG) chip. A microfluidic environment enabled precise control over the processing parameters, and therefore high batch-to-batch reproducibility and robust production of SNPs with a very narrow size distribution could be realized. Digitally adjustment of the mixing ratios of the building blocks on the DMDG chip allowed us to rapidly scan a variety of synthesis conditions without consuming significant amounts of reagents. Nearly uniform SNPs with sizes ranging from 35 to 350 nm were obtained and characterized by transmission electron microscopy and dynamic light scattering. In addition, we could fine-tune the surface chemistry of the SNPs by incorporating an additional building block functionalized with specific ligands for targeting cells. The sizes and surface properties of these SNPs correlated strongly with their cell uptake efficiencies. This study showed a feasible method for microfluidic-assisted SNP production and provided a great means for preparing size-controlled SNPs with desired surface ligand coverage.

A diffractive microlens with a cascade focal plane along the main optical axis of the device is fabricated using a low-cost technique mainly including single mask ultraviolet (UV) photolithography and dual-step KOH:H2O etching. Based on the evolutionary behavior of converse pyramid-shaped microholes (CPSMs) preshaped over a {1 0 0}-oriented silicon wafer in KOH etchant, the first-step KOH etching is performed to transfer initial square micro-openings in a SiO2 film grown by plasma enhanced chemical vapor deposition (PECVD) and patterned by single mask UV-photolithography, into CPSMs with needed dimension. After completely removing a thinned SiO2 mask, basic annular phase steps with a relatively steep sidewall and scheduled height can be shaped in the overlapped etching region between the neighboring silicon concave-arc microstructures evolved from CPSMs through the second-step KOH etching. Morphological measurements demonstrate a desirable surface of the silicon microlens with a roughness in nanometer scale and the feature height of the phase steps formed in the submicrometer range. Conventional optics measurements of the plastic diffractive microlens obtained by further hot embossing the fine microrelief phase map over the nickel mask made through a common electrochemical method indicate a highly efficient cascaded focusing performance.