Loading presentation...

Present Remotely

Send the link below via email or IM


Present to your audience

Start remote presentation

  • Invited audience members will follow you as you navigate and present
  • People invited to a presentation do not need a Prezi account
  • This link expires 10 minutes after you close the presentation
  • A maximum of 30 users can follow your presentation
  • Learn more about this feature in our knowledge base article

Do you really want to delete this prezi?

Neither you, nor the coeditors you shared it with will be able to recover it again.


SCI Final Presentation 1

No description

Sharada Dharmasankar

on 28 April 2010

Comments (0)

Please log in to add your comment.

Report abuse

Transcript of SCI Final Presentation 1

The Effect of Water Filter Thickness on Bacteria Killing Ability By Sharada Dharmasankar, Eric Lin, Hassan Qureshi, and Kenny Wang Introduction 1.8 million people a year die because of poor water quality and water borne illness
Using antibacterial agents in water filters helps
Silver is used as an antibacterial agent; silver nitrate in the eyes of newborns
We aimed to utilize silver in our water filter, as well as analyze the impact that thickness had on killing rate
Goal: 99.99% efficiency
Hypothesis The hypothesis of this experiment is that the thicker the filter, the more effective it will be in killing bacteria. Namely, the filters in order of effectiveness will be the 22mm thick filter, the 16mm, the 7mm, and lastly, the 5mm filter. Materials • Agar plates
• Weakened strain of E. coli
• De-ionized (DI) water
• NaCl
• Erlenmeyer flasks
• Graduated cylinders
• Clay
• Sawdust
• Granulated 30-50 nm silver
• Paintbrushes
• Plastic cones to mold clay onto
• Funnel
• Denatured Ethanol, to sterilize
Methods Make a solution of bacteria with e. coli and .9% saline solution. This will be used as a solution of 'dirty water' to be cleaned.
In order to make the filters, create a mixture that is 1 part clay and 1 part sawdust. Put this on the conical mold. Remove it and fire it.
Paint the filters with a solution of silver. The bacteria solutions will be run through it.
Both, the solution of bacteria (and its serial dilutions) and the filtrate (and its serial dilutions) will be plated. This helps determine the killing rate.
Results Filter Thickness (mm) Percent of Bacteria Killed
5 99.99
7 99.999
16 99.99
22 99.999
One-sample t-test
Mean: 0.999954
Standard: Error2.20454E-05
T value: -2.086602373
P value: 0.105234122
Conclusion Cannot conclusively say that killing rate increased with thickness
Source of error comes from mistakes in measuring filter thickness
Exceeded our goal of 99.99% killing rate
According to t-test, we conclude that our killing rate is statistically equivalent to 100%.
Acknowledgements Ms. O'Leary and Dr. Carlson for support and mentoring
Dr. Scheppler and Jamie Tweedle for letting us use Grainger's facilities
Fellow students, Dane Christianson, Mike Gleeson, Melissa Tao, Weili Zheng for working on a related project; additionally, Anil Vaitla for providing images
Prof. Manny Hernandez from NIU for inspiration with silver
Mr. Sewell, Mr. Urbanski, and Dr. Dosch for support and additional materials

Full transcript