Bicycle without a chain, which can be collapsed in a split-second, self-propelled leaf vacuum and non-flammable polyurethane foam are examples of Polish inventions, the authors of which were awarded at foreign fairs and exhibitions. They spoke about their inventions in Warsaw. Bicycle without a chain, with front wheel drive, was invented by Marek Jurek from Warsaw. He built a prototype, which he uses every day to move around the city. He developed the solution, because he needed a bike that can be collapsed easily and quickly to easily (despite the large circles with a diameter of 29 inches) fit it in a car or elevator. With custom construction solutions, the new bike turned out to be more efficient than classical bicycles. The use of front-wheel drive makes \"the whole system better adapted to humans, reduces the aerodynamic resistance and losses that in bicycles with classic design are related to chain deformation\" - explained Marek Jurek, the author of the patent in Poland. He said that his design \"reduced the impact of variable moments of the forces that occur when pedalling and affect the steering\" which helps maintain direction and balance, even without using hands. \"I have been riding it for a year and would not switch to classic bike, because this one is better, very efficient. I’m faster on the cycle path without getting tired\" - assured the inventor. With his bicycle, Marek Jurek won a gold medal at the 63rd International Trade Fair \"Ideas, Inventions, New Products\" (iENA) 2011 in Nuremberg. Together with several other Polish inventors awarded abroad, he received the medal and diploma in Warsaw from the president of Promotion Agency Inventor (which represented the inventor at the international trade fair) Wojciecha Kó?eczko, and the of the president the Main Council of the Research Institutes Prof. Leszek Rafalski. Among the winners was also Magdalena Danowska of Business and Innovation Centre of Gda?sk University of Technology. She won silver medal at iENA and bronze at Archimedes exhibition in Moscow for her paper \"New generation of inflammable polyurethane foams\". The foam resembles ordinary polystyrene, but it is are four times more resistant to compression, and non-flammable. Their production process uses polyglycerol, which is a byproduct in the production of biofuels, which \"reduces the foam production costs and allows to manage waste\" - explained Danowska. The exceptional durability of the new foam is a result of a nanofiller based on layer aluminosilicate. \"Rigid foam is an ideal material for building insulation. They have very good insulating properties. Since they are self-extinguishing material, in case of fire they limit the emission of toxic gases, and inhibit the spread of fire. Their price is lower or comparable with the price commercially available foams\" - Danowska said in an interview with PAP. She revealed that entrepreneurs from Japan are interested in the project. \"Self-propelled leaf vacuum\" is a project awarded in the second edition of the Academy of Young Inventors Competition, designed by Bartosz Walentyn from the Nicolaus Copernicus University. \"In autumn, many city parks administrators and private garden owners have a problem with leaves on the lawns. I had to rake a lot every year myself. So I decided to invent a self-propelled leaf vacuum\" - he said in an interview with PAP. The device runs on a lawn like a mower, but instead of a knife it has two rollers collecting leaves. It collects dry, rotten, and pressed leaves, crushes them and sucks into a bag. In Bartosz Walentyn’s vacuum cleaner one engine drives the rollers and the whole vehicle, the other the suction-crushing machine. The inventor, however, wants to simplify the design, so that one engine drives the whole unit. Walentyn noted that a variety of hand-held leaf blowers or vacuums that have to be pushed are available today. \"But there is no device, on which the user could sit and drive. My invention can be operated on larger areas without fatigue\" - he emphasised. Among Polish inventors awarded abroad, who received medals in Warsaw, were also the authors of the project \"Intelligent Comprehensive Vehicle Identification System - ISKIP\" from the Institute of Road and Bridge Research in Warsaw (iENA gold medal, silver medal at ARCA exhibition in Zagreb), Micha? Ska?ecki from Wroc?aw University of Technology - author of the \"Steam Boiler Simulator Using Artificial Neural Networks\" (winner of the third edition of the Academy of Young Inventors Competition) or Karol Kowalczuk of Warsaw University of Technology with the project \"Fog Lamp\" (winner of the first edition of the Academy of Young Inventors Competition).