Recently, it was demonstrated that the insertion of TCO layers between the compound cells of tandem cells allows a shift of current generation from the bottom to the top cell [1]. This concept is particularly useful to increase the performance of a-Si:H/μc-Si:H tandem cells. In this paper we analyse experimental and optical modelling results of very different tandem cell structures in order to ...

Gas hydrates, solid composites of biogenically derived gasses (mainly methane) combined with water ice, may be present in marine sediments, especially at continental margins, under the correct pressure and temperature conditions. Gas hydrates are detected by direct sampling, and inferred from seismic reSection data when a strong bottom-simulating reSector (BSR) is produced by the seismic veloci...

A rock physics model was established to calculate the P-wave velocity dispersion and attenuation caused by squirt flow of fluids in gas hydrate-bearing sediments. The critical hydrate saturation parameter introduced describe different ways concentration, including mode pore filling co-existence particle cementation. Rock physical modeling results indicate that is insensitive increase for fillin...

Seafloor heat flow measurements are utilized to determine the geothermal regime of Danube deep-sea fan in western Black Sea and presented larger context regional gas hydrate occurrences. Heat data were collected across paleo-channels water depths 550–1460 m. levees ranges from 25 30 mW m?2 but is up 65 on channel floors. Gravity coring reveals sediment layers typical Sea, consisting three late ...

Handling of bulk solids takes place in gasifiers either at the feed point or at the section of discharging waste and residues of the combustion and gasification. In large gasifiers, significant amounts of waste are expected to be produced, hence a proper gasifier design that allows an effective discharge of the waste from its bottom is essential for a smooth and reliable gasification. Poor gasi...

We have designed a high-efficiency broadband grating coupler for coupling between silicon-on-insulator (SOI) waveguides and optical fibers. The grating is only 13 microm long and 12 microm wide, and the size of the grooves is optimized numerically. For TE polarization the coupling loss to single-mode fiber is below 1 dB over a 35-nm wavelength range when using SOI with a two-pair bottom reflect...