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Six corrosion protection systems for offshore wind power constructions have been subjected to offshore conditions on a test site in the North Sea in three different exposure zones, namely splash zone, intermediate zone, and underwater zone. The systems included single- and multiple-layered organic coatings, metal-spray coatings, and duplex coatings. Special testing specimens were designed and manufactured and exposed to an offshore environment for three years in order to characterize particular constructive details for different corrosivity zones. The following target parameters were investigated: intensity of fouling, anti-corrosive effect, coating adhesion, coating integrity, flange corrosion, coating performance over welds, and condition of screw connections. Fouling was an issue in the underwater zone and in the intermediate zone, but it did not affect the coating corrosion protection capacity. It was found that duplex systems, consisting of Zn/Al spray metallization, intermediate particle-reinforced epoxy coating, and polyurethane top layer, provided the highest anti-corrosive effect. Mechanical damage to the coatings initiated coating delamination and substrate corrosion. Effective coating systems should be either very resistant to impact or able to compensate for corrosion of the steel. Flange connections were found to be critical structural parts in the splash zone in terms of corrosion. Notable crevice corrosion was observed at places. Except for one coating system, welds have been protected well. Welds, however, affected the corrosion of the steel inside the uncoated internal sections in the underwater samples. Coating integrity on difficult-to-coat structural parts was satisfactory for all systems.

Abstract Fabrication of solar cells with very high efficiencies currently requires extremely complex processing. In order to make photovoltaics an economical large scale source of energy, very high efficiencies have to be achieved by low-cost processing. The innovative approach for the cost-effective production of highly efficient silicon solar cells presented in this paper is characterised by only four simple and environmentally safe large-area fabrication steps. The basic processing sequence consists of: (i) mechanical surface grooving, (ii) simple diffusion or inversion, (iii) shallow angle metal evaporation, and (iv) plasma silicon nitride deposition. Cell design, fabrication techniques and processing sequences for metal-insulator-semiconductor contacted diffused n+-p junction (MIS-n+p) and MIS-inversion-layer (MIS-IL) silicon solar cells are outlined. The new simple approach turned out to be most successful, as demonstrated by mechanically grooved MIS-n+p silicon solar cells with efficiencies above 21% using exclusively aluminium as metallisation.

Abstract For the first time the electrical conductivity of bamboo biographite-based material reported a ground-breaking milestone of 4.4 × 104 (S/m). This reported conductivity by far exceeded all previous reported conductivity measurements obtained from renewable carbon. Controlled high-temperature thermal carbonization of biomass, notably Asian bamboo, at extended residence times elicited surprising growth of nano-layered biographitic structures with a layer-to-layer distance of less than 0.3440 nm. Moreover, thermodynamically dispersed bamboo and pine biographitic nano-layered carbon-based lightweight composites in a polyamide matrix were found to be intrinsically conductive both thermally and electrically. Electromagnetic interference (EMI) shielding device made from bamboo renewable carbon/cellulose nanofiber (CNF) composites possesses EMI shielding effectiveness (SE) of ∼23 dB. These results constitute a new advancement in the materials science of nano-layered graphites from renewables and their applications as EMI filtering devices and as electrode materials in air cathodes, electronics, supercapacitors in energy storage devices, and thermal management of batteries and sensors.

Abstract This article announces the availability of patented technology and production equipment for the manufacture of thin-film CdTe photovoltaic (PV) modules capable of providing utility scale power. It further discusses ongoing R&D, for the period 2000–2010, which will produce PV power at costs competitive with conventional fossil fuel systems.

Abstract Cobalt oxide and cobalt oxide–silver selective surfaces were prepared in a galvanostatic mode by means an electrodeposition bath, using different deposition times, on stainless steel substrates. Later, the roughness factor of the selective surfaces, were determined in order to establish one relation with the electrodeposition time and the solar absorptance of the black cobalt and black cobalt–silver coatings.

Abstract Polymer containing isatin was synthesized by super acid-catalyzed carbon–carbon coupling reaction. Propylsulfonic acid was grafted on isatin unit by substitution reaction with potassium salt of 3-bromo-1-propanesulfonic acid. The sulfonic acid composition was regulated at 25–80 mol % of propylsulfonic acid in order to achieve expected ion exchange capacity of maximum 2.0 meq/g. The copolymers were of high molecular weight (inherent viscosity, ηinh = 1.2 dL/g) to afford a tough membrane by solution casting. All these membranes were casted from dimethylsulfoxide (DMSO). The structural properties of the synthesized polymers were investigated by 1H NMR spectroscopy. The membranes were studied by ion exchange capacity (IEC), water uptake, dimensional stability and proton conductivity assessment by comparing with Nafion®. As increasing the IEC values, the small hydrophobic components induced high proton conductivities and proton diffusion coefficients. These kinds of membranes without ether linkages showed low water swelling as well.

Abstract In terms of supercapacitor electrode materials, biomass derived carbon electrodes are gaining much attention as a viable option for practical applications. Obtaining unique carbon nanostructures can significantly promote the electrochemical performance. Waste potato peel (WPP) derived hierarchical porous carbon materials with heteroatoms doping can boost the development of efficient and economical electrodes with improved charge storage capabilities. Here, we report sulfur and phosphorus co-doped porous activated carbon (S, P/PAC) as an effective supercapacitor electrode material with a large specific surface area. More importantly, the S, P/PAC not only acquires dual heteroatoms doping for promoting capacitive performance but also possesses fascinating porous features which are beneficial to shorten ion adsorption distances and enlarge the contact area. The electrode exhibits a high specific capacitance of 323 F g−1 at 1 A g−1, acceptable rate capability and good cycling stability after 5000 cycles. The constructed symmetric supercapacitor device with a wide operational potential window of 1.6 V achieves a maximum energy density of 45.5 Wh kg−1 at a power density of 800 W kg−1 with an improved long cycle life (94.3 retention after 10 000 consecutive cycles).