This typically happens because you have not yet entered a think-cell license key, or your current key reached the end of the validity period. When you close the license key window with OK, PowerPoint crashes. With most versions of Microsoft Office, a think-cell error message appears, 'APIERR 1400 Invalid window handle'. Think-cell is a German computer software company founded in April 2002 and headquartered in Berlin, Germany. The Fraunhofer Society spin-off focuses upon the creation of Microsoft PowerPoint and Excel add-in products. Rta Megane 2 Rapidshare Download. The company's main product – think-cell – aims to facilitate the creation of charts, e.g., bar charts,.

The use of solar energy is expanding worldwide but the efficiency of silicon solar cells has made very little progress in the last few decades. Could perovskite solar cell be the answer to high-efficiency solar power? Conventional solar cells today are made of silicon with power conversion efficiencies that have been stagnating in the low-20% range for about 15 years. This might strike you as bizarre, since glancing at data from the National Renewable Energy Laboratory (NREL) reveals theoretical efficiencies that approach 50%. Reported timeline of solar cell energy conversion efficiencies since 1976 from the National Renewable Energy Laboratory refers to what portion of sunlight energy is converted to electricity via the use of photovoltaic technology. So why are we still using what might appear to be dinosaur technology when it comes to relying on low-efficiency silicon solar cells?