3 resultados para Church work with immigrants
em Chinese Academy of Sciences Institutional Repositories Grid Portal
Resumo:
The membraneless biofuel cell (BFC) is facile prepared based on glucose oxidase and laccase as anodic and cathodic catalyst, respectively, by using 1,1'-dicarboxyferrocene as the mediators of both anode and cathode. The BFC can work by taking glucose as fuel in air-saturated solution, in which air serves as the oxidizer of the cathode. More interestingly, the fruit juice containing glucose, e.g. grape, banana or orange juice as the fuels substituting for glucose can make the BFC work. The BFC shows several advantages which have not been reported to our knowledge: (1) it is membraneless BFC which can work with same mediator on both anode and cathode; (2) fruit juice can act as fuels of BFCs substituting for usually used glucose; (3) especially, the orange juice can greatly enhance the power output rather than that of glucose, grape or banana juice. Besides, the facile and simple preparation procedure and easy accessibility of fruit juice as well as air being whenever and everywhere imply that our system has promising potential for the development and practical application of BFCs.
Resumo:
In this paper, five Pt3Sn1/C catalysts have been prepared using three different methods. It was found that phosphorus deposited on the surface of carbon with Pt and Sn when sodium hypophosphite was used as reducing agent by optimization of synthetic conditions such as pH in the synthetic solution and temperature. The deposition of phosphorus should be effective on the size reduction and markedly reduces PtSn nanoparticle size, and raise electrochemical active surface (EAS) area of catalyst and improve the catalytic performance. TEM images show PtSnP nanoparticles are highly dispersed on the carbon surface with average diameters of 2 nm. The optimum composition is Pt3Sn1P2/C (note PtSn/C-3) catalyst in my work. With this composition, it shows very high activity for the electrooxidation of ethanol and exhibit enhanced performance compared with other two Pt3Sn1/C catalysts that prepared using ethylene glycol reduction method (note PtSn/C-EG) and borohydride reduction method (note PtSn/-B). The maximum power densities of direct ethanol fuel cell (DEFC) were 61 mW cm(-2) that is 150 and 170% higher than that of the PtSn/C-EG and PtSn/C-B catalyst.
Resumo:
本文给出了移动机器人的虚力导航和运动规划系统.这种方法结合最小方差估计算法(LM SE)能有效地对机器人进行实时导航和避撞.在预测过程中,根据导航的不同阶段和预测误差的变化情况,采用Fuzzy 规则动态地调整误差函数中的权重,使预测过程尽可能准确.导航算法的基本思想是首先通过预测算法来获得移动机器人的运动信息,然后虚力系统根据预测信息决定机器人的未来运动,仿真结果表明该方法实时性好,能准确躲避障碍物并且到达目标点