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Hybrid battery energy storage system (HBESS) consists of high power density battery and high energy density battery will have a bright future in special isolated DC microgrid conditions such as the all-electric ships and all-electric airplanes, which have strict limitation on storage capacity and size. In this study, a new decentralised control strategy based on mixed droop is proposed to HBESSs with considering the batteries. In decentralised control strategy, conventional V–I droop controller is utilised to high energy density battery to mainly supply the steady power, I–V droop controller is utilised to high power density battery to respond to power change and supply a few steady power. In addition, dynamical state-of-charge (SoC) regulation algorithm is utilised to reassign the battery power according to their own SoC. The power coordination of the high energy density batteries and high discharge rate batteries is achieved by adjusting the values virtual impedance and reference input voltage. Case study shows that the proposed control strategy is flexible and efficient.

The network reconfiguration of a vessel power system (VPS) is one of the most important approaches to restore its power supply and improve its survivability. The current research on the reconfiguration mainly focuses on the selection and optimisation of recovery paths, with little consideration of the influence of recovery time series. The limited capacity of the VPS, many loads of the motor load and large starting current have a great impact on the electric-energy quality of the power system. Therefore, the different recovery time series will affect the system performance and the recovery rate. The effect of the different recovery time series on the network reconfiguration and fault control has been analysed through the simulation of target network to determine the corresponding relationship between the residual power-supply capacity, the load recovery time series and the recovery rate, which can provide the basis of studying an optimal recovery strategy.

The miRNAs play important roles in regulating myocardial fibrosis. The purpose of this study was to determine the potential roles of microRNA-214 (miR-214) in cardiac fibrosis in vitro and in vivo. In vitro experiment, Ang II-induced cardiac fibroblasts (CFBs) are transfected with pre-miR-214, anti-miR-214 and their oligo controls. Gene expression was checked by Quantitative realtime-PCR (qRT-PCR) and western blotting. In the present experiment, compared with controls, expressions of collagen type I (COL I), collagen type III (COL III), transforming growth factor (TGF)-β1, and tissue inhibitors of metalloproteinase (TIMP)-1 were all increased, but matrix metalloproteinase (MMP)-1 was reduced in CFB by Ang II treatment at both mRNA and protein levels, and these alterations were found reversed by miR-214 transfection. In vivo, an anterior transmural acute myocardial infarction (AMI) was created by occlusion of the left anterior descending coronary artery after Ad-pre-miR-214, Ad-anti-miR-214 or Ad-GFP was delivered separately. Four weeks after AMI, protein contents of COL I, COL III and TGF-β1 in tissue from border area were found increased after AMI, but impaired by overexpression of miR-214. While the expression of MMP-1 was increased by miR-214 stimulation but decreased by miR-214 inhibition. These results suggested that miR-214 exerts cardio-protective effects by inhibition of fibrosis and the inhibitory effect involves TGF-β1 suppression and MMP-1/TIMP-1 regulation. Anat Rec, 299:1348-1357, 2016. © 2016 Wiley Periodicals, Inc.

Dependence of the tensile strength of resulting carbon fiber (CF) on the preparation technologies during preoxidation and carbonization were studied systematically by a series of pilot experiments. The proper preoxidation time, preoxidation temperature, and preoxidation stretching ratio are the base of preparing high-quality CF. During precarbonization, the enhancement of the precarbonization temperature and the application of the precarbonization stretching are helpful to increase the tensile strength of CF, but the stretching ratio should be controlled carefully by on-line tension values. The tensile strength of CF increases quickly below 1200°C and then slowly above 1200°C as the carbonization temperature raises. Even though during carbonization, a proper relaxation should also be explored in order to prepare optimal CF. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008

Various sized hollow nanotubes and solid nanorods are synthesized from rutile powder (particle size ≈ 120–280 nm) using a relatively simple chemical approach in alkaline solution. The nanotubes and nanorods occur as hydrated phases: TiO2·1.25H2O and TiO2·1.0H2O, respectively. The rutile particles react in concentrated NaOH solution under hydrothermal conditions, yielding layered sodium titanate in the form of either polycrystalline nanotubes or single-crystal nanorods. The form of the product depends on the temperature and time of hydrothermal reaction: Therefore, this is a report of the template-free control of the degree of crystallinity, crystal structure, and morphology of these types of nanoscale sodium titanate products. By treating the nanotubes and nanorods with dilute HCl, the sodium ions within them could be exchanged for protons, and the morphology of the nanotubes and nanorods is retained, resulting in hydrogen titanate nanotubes and nanorods. The electrochemical performance of dehydrated hydrogen titanate nanotubes and nanorods is explored in terms of their potential performance as anode materials for lithium-ion batteries. The discharge capacity is higher for thin anatase nanorods converted from hydrogen titanate nanotubes when compared to the calcined (at 500 °C and 700 °C) products of hydrogen titanate nanorods. The significance of these findings is the possibility of fabricating delicate, nanostructured materials directly from industrial raw materials, because the natural mineral of titanium dioxide and most of the raw industrial TiO2 products exist in the rutile phase.

The formation mechanism of uniform CeO2 structure at the nanometer scale via a wet-chemical reaction is of great interest in fundamental study as well as a variety of applications. In this work, large-scale well-crystallized CeO2 nanorods with uniform diameters in the range of 20−30 nm and lengths up to tens of micrometers are first synthesized through a hydrothermal synthetic route in 5 M KOH solution at 180 °C for 45 h without any templates and surfactants. The nanorod formation involves dehydration of CeO2 nanoparticles and orientation growth along the 〈110〉 direction in KOH solution. Subsequently, gold nanoparticles with crystallite sizes between 10 and 20 nm are loaded on the surface of CeO2 nanorods using HAuCl4 solution as the gold source and NaBH4 solution as a reducing agent. The synthesized Au/CeO2 nanorods demonstrate a higher catalytic activity in CO oxidation than the pure CeO2 nanorods.