Solar cell process development in the european integrated project crystalclear

CrystalClear is a large integrated project funded by the European Commission that aims to drastically reduce the cost of crystalline Si PV modules, down to 1 Euro/Wp. Among the different subprojects, the one dealing with the development of advanced solar cells is relatively large (with 11 partners out of the 15 Crystal Clear partners taking part) and has a crucial role. The goal of the subproject is to develop cell design concepts and manufacturing processes that would enable a reduction in the order of 40% of the cell processing costs per Wp. In this paper, we give an overview of all the development work that has taken place in the CrystalClear solar cells subproject so far. World class results have been achieved, particularly on high efficiency cells on Si ribbons, and on industrial-type solar cells on very thin (120 (j.m thick) substrates

Structure and conformation of 2 beta,3 beta-epoxyestr-5(10)-en-1,4, 17-trione, spectroscopic and X-ray crystallographic studies

Colourless single crystals were isolated as by-product during the synthesis of steroidal A-ring substituted 1,4-quinones (and epoxyquinols), as synthetic products with antibiotic and antitumor properties. Its structure was proposed by comparing IR, UV, H-1 and C-13 NMR spectra to the ones of quinone 2 and independently determined by an X-ray analysis, as 2 beta,3 beta-epoxyestr-5(10)-en-1,4,17-trione. Crystals belong to the monoclinic system with space group P2(1): a = 6.767(3) Angstrom, b = 7.097(5) Angstrom, 15.748(5) Angstrom, beta = 97.070(5)degrees, V = 750.6(8) Angstrom(3), Z = 2, D-x = 1.329 Mg m(-3), mu(Mo K-alpha) = 0.093 mm(-1). The structure was solved by direct methods and refined to a final R = 0.064 for 1729 reflections with I gt 2 sigma(I). The steroidal skeleton with chiral centre at C13 possesses the S configuration defining beta-orientation of O2 atom bridging C2 and C3 atoms and beta-oriented methyl group bonded to C13 atom. The best plane through the ring A and epoxy ring plane form an angle of 89.6(2)degrees. Conformational analysis of the steroid rings are performed by calculating the ring puckering parameters and asymmetry factors. The conformation of the A ring is screw-boat S-1(6), ring B half-chair H-4(3), ring C chair C-1(4), and the five-membered D ring is half-chair H-2(1) conformation. The crystal structure is stabilised by the weak C-H ... O hydrogen bonds and van der Waals interaction. (C) 2000 Elsevier Science B.V. All rights reserved

Working time in West Germany The effects of changes in pattern and duration

10.00SIGLELD:82/09346(Working). / BLDSC - British Library Document Supply CentreGBUnited Kingdo