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A metastable bimetallic ZnCo-ZIF-L topochemical phase conversion and subsequent pyrolysis strategy was developed to fabricate Co–N–C@NCNTs, which exhibit excellent ORR/OER performance with an overpotential gap of 0.748 V.

Dual-metallic Fe/Co/N co-doped porous carbon nanosheets (Fe/Co–N–C NSs) with hierarchical porous structures and abundant exposed bimetallic Fe/Co–Nx active sites can be utilized as efficient ORR electrocatalysts.

Transition metal-nitrogen-carbon (TM-N-C) catalysts have been intensely investigated to tackle the sluggish oxygen reduction reactions (ORRs), but insufficient accessibility of the active sites limits their performance. Here, by using solid ZIF-L nanorods as self-sacrifice templates, a ZIF-phase-transition strategy is developed to fabricate ZIF-8 hollow nanorods with open cavities, which can be subsequently converted to atomically dispersed Fe-N-C hollow nanorods (denoted as Fe

For the problems of wear real-time, compatibility and intelligence, we have designed computer network test and failure diagnosis system based on VXI bus technology. The hardware and software of the system have been improved. To implement real time, high speed data communication and transmission, the functions of VXI test board have been extended. The degree of intelligence and automatization has been improved through introducing expert system in the design of software. These will provide new references for improvement of existing test and diagnosis systems of computer network equipments.

According to the assist characteristic of induction motor in Electro Hydraulic Power Steering (EHPS), a slip frequency control system for EHPS system in electric vehicle applied to Electric Control Units (ECU) has been proposed. We analyzed induction motor operating characteristic in EHPS and established a model, and simulated based on Matlab/Simulink. The simulation shows that the proposed control strategy can obtain good control effects, the proposed algorithm is verified.

This work presents a broadband optical transparency structure consisting of a metal film perforated by an array of strip cavities. We theoretically demonstrate the metal film with side-coupled grooves system in model structure by the coupled model theory. The transparent light with a great bandwidth is obtained as a result of the tunneling and the resonance effect of the cavities by employing the finite-difference time-domain method simulation. By changing the parameter of the grooves in the structure, the transparency property shows a great adjustment in both wavelength and bandwidth. These structures have potential applications for transparent conductor devices.

In this paper, a novel metal structure that integrates double continuous Au films and double aligned gold (Au) non-close-packed ellipsoidal nanoparticle arrays is proposed. The optical features of this structure are simulated by using the three-dimensional finite-difference time-domain (3D-FDTD) method. Bimodal plasmonic resonances with the highest transmission up to 74% and 66% (corresponding to the short and long-wavelength, respectively) are achieved. This proposed structure with sub-wavelength size may provide fascinating applications in optoelectronic devices such as transparent conductors and conductive devices, slow light devices, highly sensitive sensors.

A novel plasmonic passband filter consisting of metal-insulator-metal perforated with an array of rectangular grooves and circular holes is proposed and demonstrated. The transmission property of the proposed structure is obtained by employing the finite difference time domain with perfectly matched layer absorbing boundary condition. The result reveals that a passband with high transmission can be achieved. And the transmission peak position can be efficiently tuned by changing the factors of the structure, such as the sizes of circular holes and grooves. The proposed filter has potential applications for integrated optoelectronic devices due to its miniaturized size.

We propose and theoretically study a novel plasmonic nanostructure composed of two malposed silver (Ag) triangular nanocylinder arrays by the finite-difference time-domain (FDTD) method. The excitation of the localized surface plasmons (LSPs) of the metal triangular nanocylinders, and the strong interaction coupling between LSPs contribute to the enhanced transparency in the visible and near-in region (NIR). The transparency response in the proposed nanostructure is modified by changing the gap distances between two adjacent triangular nanocylinders, and the dielectric environments. The tunable enhanced optical transparency of the proposed nanostructure provides potential applications in sensors and plasmonic filters.

Making a continuous metal film with near-unity transparency has received more and more attention in recent years because of its potential applications for various optoelectronic devices. Here, we theoretically show that a high tunable plasmon-induced transparency metal film structure can be performed by double continuous metal films inserted with a two-dimensional hexagonal lattice array of plasmonic nanopariticles. The proposed structure shows near-unity anti-reflection and intensively enhanced transmission via the cooperative effects of strong resonant near-field light input and output coupling by the plasmonic array and the excitation of surface electromagnetic waves of the metal films. The optical response can be efficiently mediated by varying the sizes of nanoparticles and the separated distance between the metal array and the metal films. With the merits of high transparency, sub-wavelength sizes and wholly retained metal characteristics including high conductivity via using the pure metallic materials, the structure proposed here suggests various potential applications in optoelectronic integrated circuits.

This study aimed to explore the protective effect of total flavonoids in Caragana against hypoxia/reoxygenation (H/R)-induced injury in human brain microvascular endothelial cells (BMECs). Human BMECs were selected and assigned into control, H/R, H/R+NMP, H/R+Low dose, H/R+Moderate dose, H/R+High dose groups. MTT and Transwell assays were used to detect cell viability and migration, respectively. Cell adhesion rate and tube formation were also detected. Real-time polymerase chain reaction (RT-PCR) and Western blotting were performed to test HIF-1α, VEGF and Notch1 mRNA and protein expressions. Compared with the H/R group, the cell viability rates in the H/R+NMP, H/R+Moderate dose and H/R+High dose groups were increased. The cell adhesion rates in the H/R+NMP, H/R+Moderate dose and H/R+High dose groups were significantly different from those in the H/R group. As compared to the H/R group, the cell migration abilities in the H/R+NMP, H/R+Moderate dose and H/R+High dose groups were enhanced. Compared with the H/R group, the number and length of tubes of BMECs in the H/R+NMP, H/R+High dose and H/R+Moderate dose groups were increased. HIF-1α, VEGF and Notch1 mRNA and protein expressions were higher in the H/R+Low dose, H/R+Moderate dose and H/R+High dose groups than in the H/R group. These findings revealed that total flavonoids in Caragana can protect BMECs from H/R-induced injury in a dose-dependent manner and it also may promote angiogenesis in BMECs by activating HIF- 1α-VEGF-Notch 1 signaling pathway.

In this paper, the hemodynamic characteristics of blood flow and stress distribution in a layered and stenotic aorta are investigated. By introducing symmetrical and unsymmetrical stenosis, the influence of stenosis morphology and stenotic ratio on the coupled dynamic responses of aorta is clarified. In the analysis, the in-vivo pulsatile waveforms and fully fluid-structure interaction (FSI) between the layered elastic aorta and the blood are considered. The results show that the fluid domain is abnormal in the stenotic aorta, and the whirlpool forms at the obstructed and downstream unobstructed regions. The maximum wall shear stresses appear at the throat of the stenosis. Downstream region appears low and oscillated shear stresses. In addition, along with the increase of the stenotic ratio, the amplitude of the maximum shear stress will be intensively increased and localized, and the sensitivity is also increased. In the aorta with unsymmetrical stenosis, the Von Mises stresses reach the peak value at the side with the surface protuberance, but they are reduced at the side with no protuberance. The sign variation of the layer interface shear stresses near the throat indicates the variation of the shear direction which increases the opportunity of shear damage at the transition plane. Moreover, the shear stress levels at the fluid-solid and intima-media interfaces are higher than that at the media-adventitia interface. The unsymmetrical stenosis causes higher stresses at the side with the surface protuberance than symmetrical one, but lower at the side with no protuberance. These results provide an insight in the influence of the stenosis, as well as its morphology, on the pathogenesis and pathological evolution of some diseases, such as arteriosclerosis and aortic dissection.

Effects of Pr6O11 doping on the microstructures and the electrical properties of Bi4Ti3O12 (BIT) were investigated using dense ceramics, which were prepared by a conventional ceramic technique. For all the samples, X-ray diffraction (XRD) analyses revealed Bi-layered perovskite structures, and the scanning electron microscope (SEM) micrographs showed well developed plate-like morphologies with random orientations. The P-E hysteresis loop of samples measured at room temperature exhibited a large remnant polarization and a low coercive field. In addition, the DC current-voltage properties measured at different temperature from RT to 550 degreesC were discussed. Results indicate that Pr6O11 can be a good additive to improve the properties of Bi4Ti3O12. (C) 2004 Elsevier B.V. All rights reserved.

Metal structures with high optical transparency and conductivity are of great importance for practical applications in optoelectronic devices. Here we investigate the transparency response of a continuous metal film sandwiched by double plasmonic nanoparticle arrays. The upper nanoparticle array shows efficient light trapping of the incident field, acting as a light input coupler, and the lower nanoparticle array shows a light release gate opening at the other side, acting as the light output coupler. The strong near-field light–matter interactions of the nano-scale separated plasmonic nanoparticles, the excitation of surface plasmon waves of the metal film, and their cooperative coupling effects result in broadband scattering cancellation and near-unity transparency (up to 96%) in the optical regime. The transparency response in such a structure can be efficiently modified by varying the gap distance of adjacent nanoparticles, dielectric environments, and the distance between the plasmonic array and the metal film. This motif may provide a new alternative approach to obtain transparent and highly conducting metal structures with potential applications in transparent conductors, plasmonic filters, and highly integrated light input and output components.