Abstracts from Winning Projects
The following abstracts are from projects that won best of fair awards at GNSEF in 2011.
Using Aquatic Plants to Remove Water Contaminants
Cyanobacteria (blue-green algae) and lemna minor (duckweed) were used to remove water containing various concentrations of nitrate and copper ions. There were two phases to the experiments. The first phase involved placing a solution of 22.3 ppm nitrate water into a beaker that contained algae and duckweed. The water was then tested with a Hach DR-2000 spectrometer to determine the concentration (and thus the percentage of reduction) after a period of time. The duckweed showed an overall reduction of 48%. The algae showed a reduction of 52%. Phase two involved injecting cyanobacteria into commercially available bubble wrap and holes were placed on both sides and mounted into a plastic tube. Solutions of nitrate and copper water were run through the system. The cyanobacteria had an overall reduction of 33%in the nitrate solution, and a reduction of 39% in the copper solution. The bubble wrap injected with cyanobacteria had a reduction of 6.6% in nitrate levels each time the solution was placed through the system. Likewise, the system removed the copper ions with a reduction of 7.8%each time the solution was run through it. Algae placed in the bubble wrap can be kept for long periods of time, as it is still viable to reduce ions even after three weeks. Also, when inside the bubble wrap, it will not leak out into the water that needs purifying. It can be moved easily to runoff sites, and will be viable regardless of the time spent in shipping, and it is not an expensive solution.
Factors Affecting the Susceptibility of High School Students to NIHL due to iPods
The volume in which teenagers listen to their iPods is a health risk factor for noise-inducedhearing loss. This study explores this statement by answering the question: What factors influences the susceptibility of students to noise-induced hearing loss due to iPods at my high school? In order to model the student population at my high school, a survey was conducted on a sample of 260 students. The survey was stratified by grades and four classes were randomly selected from each grade using a random number generator. The survey includes questions about how loud (in dB) teenagers are listening to their music, how long teenagers are listening to their music and what listening habits contribute to their volume levels. The survey also asks for demographic information such as gender and age. In addition, a Sound Pressure Level Meter was used to measure the actual volume of the headphones that the students carry with them on the day of the survey. This survey does not test for actual hearing damage in the students. Neither does it cover populations outside my high school.From the data gathered in this survey, there was no significant difference in the listening levelsfrom grade to grade. The difference between listening levels of males and females was found to bestatistically significant. (p=0.011) Students with lower GPAs tend to listen to music at a louder level. Students in non-honors classes also listened to music at a higher volume. (p=0.0085) However, the measurements of volume levels using the Sound Level Pressure Meter do not take into account the type of headphones used. Future studies should investigate the role that the type of headphones used have on the volume levels.
