Who's calling? <a href=" http://www.spacecake.co.uk/omeprazole-20-mg-obat-untuk-apa.pdf ">buy omeprazole 20 mg uk</a> "We've demonstrated that the tailoring of optical properties at high temperatures is possible," Braun said. "Hafnium and tungsten are abundant, low-cost materials, and the process used to make these heat-resistant emitters is well established. Hopefully these results will motivate the thermophotovoltaics community to take another look at ceramics and other classes of materials that haven't been considered."