First Prize: Heather Rodgers� 1215� Loudoun Valley High School
As water mixes with heavy metals such as Pb, Cu and Fe, toxic water is formed, polluting the environment.� Traditional means of removal is cosly.� The purification of toxic water will be tested using the common plant, Nasturtium Officinale.� The plants came from Endless Summer harvest in Purcellville, Virginia.� One plant was placed in a mason jar filled with 100 mL of either Pb(NO3)2, Cu(NO3)2, Fe(NO3)3, or deionized water.� The plants were then placed in a growth chamber where they received a constant temperature of 70o F and 12 hours of sunlight for six days.� After six days 0.14 g of the plant�s roots and leaves were removed, dried, crushed, and then placed in a test tube with 1mL of 1M HCl and 4mL of deionized water.� The solution was mixed and then the actual plant was filtered out and then placed in a Spec 20.� The recorded percent transmitted was then compared to a preconfigured table to see how much of the metal the plant had absorbed.� The average amount of Pb absorbed was between 0.025 M and 0.0125 M while the average amount of Cu absorbed was between 0.025 M and 0.0125 M, and an insignificant amount of Fe was absorbed.� Nasturtium Officinale was found to remove Pb and Cu from the water while Fe was not removed.� These results could be used to clean up the environment in a cost-effective way.
Second Prize: Ian Pearson 1107, Dominion High School
Chitosan is the second most abundant polysaccharide in nature.� Utilization of the remedial properties of Chitosan can prevent bacteria from spreading and/or eliminate harmful substances in the environment.� The intent of this research was to determine whether chitosn has any effect in preventing the spread of Escherichia coli in wastewater and on kidney stents as well as whether it had the ability to eliminate sulfur from anthracite coal-mining wastewater.
Three testing scenarios were created.� In the first, two tanks containing Escherichia coli and PVC pipes were used to simulate actual wastewater treatment facility environments.� After an initial period of 30 days, chitosan was added to one of the tanks.� Secondly, kidney stents were pre-coated with a chitosan paste and submerged into a container containing an Escherichia coli solution.� The container was then place into the incubator.� Lastly, sulfur was extracted out of both anthracite coal and anthracite coal soaked in a chitosan paste.
The null hypothesis, that chitosan would not be an efficient biological remediant, was rejected.�� Chitosan was able to reduce the amount and spread of bacteria found on the PVC pipes and kidney stents.� The effect of chitosan on sulfur reduction was greatly significant.� Sulfur was reduced by an average of 88.1 percent.� Further research may help develop an improved chitosan paste which can completely prevent the spread of bacteria and certainly merits further investigation as a biological remediant.
Third Prize: Timothy Gondo 1002, Broad Run High School
The effects of blade design on the ability of a wind powered generator to adequately supply power to run a laptop computer, for a useful amount of time, was investigated by building a wind powered generator and collecting 2 samples for each blade design and wind speed.
Four blade designs were tested. They are as follows:
-4 30 inch long blades 4s
-8 30 inch long blades 8s
-4 30 inch long symmetrical blades 4s 2
-4 50 inch long blades 4L
Significant differences were found in the power output of 2 of the blade designs variants 4s2 and 4L, which the 3rd blade design variant 8s produced similar power output.� Blade design must not have a significant impact on power output and the 4s design produced the highest mean power output.
Based on the test results, it is possible to power a laptop from a small wind turbine generator if the generator was built correctly.� The 19 watts of power that it was capabile of producing with the proper DC motor would easily produce enough power over a 24 hour period to power a laptop computer for at least several hours per day.
Adding additional blades, or making blades longer did not increase power production and in fact it had the opposite effect.
The contributions of this project are that it was demonstrated that a laptop computer could be powered by a small homebuilt windmill generator device, that a simply constructed 4 blade design was the most efficient.