The effects of exchange current density, Tafel slope, system resistance, electrode area, light intensity, and solar cell efficiency were systematically decoupled at the converter-assisted photovoltaic–water electrolysis system. This allows key determinants of overall efficiency to be identified. On the basis of this model, 26.5% single-junction GaAs solar cell was combined with a membrane-electrode-assembled electrolysis cell (EC) using the dc/dc converting technology. As a result, we have achieved a solar-to-hydrogen conversion efficiency of 20.6% on a prototype scale and demonstrated light intensity tracking optimization to maintain high efficiency. We believe that this study will provide design principles for combining solar cells, ECs, and new catalysts and can be generalized to other solar conversion chemical devices while minimizing their power loss during the conversion of electrical energy into fuel.

Highly conductive and transparent thin films were prepared using highly purified multi-walled carbon nanotube (MWCNT) sheets. The electrical properties of the MWCNT sheet were remarkably improved by an acid treatment, resulting in densely packed MWCNTs. The morphology of the sheets reveals that continuous electrical pathways were formed by the acid treatment, greatly improving the sheet resistance all the while maintaining an excellent optical transmittance. These results encourage the use of these MWCNT sheets with low sheet resistance (450 Ω/sq) and high optical transmittance (90%) as a potential candidate for flexible display applications.

Purpose: Three-dimensional(3D) magnetic resonance(MR) pr이 ection imaging was evaluated as a noninvasive alternative to direct cholangiography fo r the assessment of its reliab ility in patients w ith obsructive jaundice. Materials and Methods: A heavily T2-weighted gradient-ec ho sequence(PSIF) was used for 3D MR pr이 ecion imaging of the biliary system in five healthy volunteers and 25 patients with obstructive jaundice. The 3D images of the bile ducts were formed by stacking consecutive coronal MR images obtained with a fast imaging method to a maximum-intensity pr 이 ection algorithm Results: In the volunteers , MR cholangiography could demonstrate the anatomy of the biliary tract in only two subjects. The extrahepatic and intraheparic bile ducts were well visualized in 23 patients with obstructive jaundice. The leve of obstruction and the grade of dilatation were dipicted with MR cholangiography in all cases. And the cause of obstruction could be determined with MR cholangiography in 18 cases , MR cholangiography was successful in two patients in whom ERCP failed. The gallbladder or dilated pancreatic duct not demonstrated by means of direct cholangiography was demonstr ated with MR cholangiography in si x cases Conclusion: MR cholangiography may be a useful adjunctive tool for the noninvasive evaluatio l"l of patients with obstructive Jaundice.

Articles you may be interested inEffect of different carrier gases and their flow rates on the growth of carbon nanotubes Phys. Plasmas 22, 043501 (2015); 10.1063/1.4916057 Growth of high-density carbon nanotube forests on conductive TiSiN supports Appl. Phys. Lett. 106, 083108 (2015); 10.1063/1.4913762Effect of hydrogen pretreatment on the spin-capability of a multiwalled carbon nanotube forest Spin-capable multiwalled carbon nanotube (MWCNT) forests that can form webs, sheets, and yarns provide a promising means for advancing various technologies. It is necessary to understand the critical factors to grow spin-capable carbon nanotubes (CNTs) in a repeatable fashion. Here we show how both the spinning capability and morphology of MWCNT forests are significantly changed by controlling the C 2 H 2 concentration and ramp rate of temperature. The acetylene gas flow was varied in the range of 0.25-6.94% by volume. The MWCNTs grown at C 2 H 2 concentrations between 1.47-3.37% are well-aligned and become spin-capable. The well-aligned forests have higher areal density and shorter distance between CNTs. The thermal ramp rate was also changed from 30 C/min to 70 C/min. A specific range of thermal ramp rate is also required to have the suitably sized nanoparticles with sufficient density resulting in higher CNT areal density for spinnable MWCNTs. A ramp rate of 50 C/min forms suitable sized nanoparticles with sufficient density to produce CNT forests with a higher areal density and a shorter tube spacing.

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