Applying Nanosensor Technology to HVAC Systems'

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Applying Nanosensor Technology to HVAC Systems.
By John Ndungu Advisor Dr. Darin Nutter
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Index

• Rationale.
• Past Weeks.
• The main problems.
• The solutions.
• The method of application.
• Activation procedure.
• Other types of sensors.
• Conclusion.
• Citations.

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Rationale

• Beginning on Sep. 18, 2001, terrorists began
  sending letters filled with anthrax spores to
  senators, media offices, and other people.
• Last year one of Dr. Nutters undergrad
  researchers, William Cantrell, investigated the
  spread of pathogens that were released in
  buildings and came up with some unnerving
  statistics.

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RationaleFigure 1.

• According to Mr. Cantrell's research, pathogens
  were able to spread through two levels of a
  building in less than 20 minutes, even if the
  doors were closed.
• These results showed him that if people were to
  have a fighting chance of escaping an infected
  building , building designers were going to have
  to implement HVAC safeguards.

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Heating, Ventilating, and Air Conditioning (HVAC)
System.
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Past weeks...

• Since I arrived my primary duties have been to
  read about nanosensors and HVAC systems and then
  come up with a theory of how to put these
  technologies together.
• Since my research was very open ended, I did not
  do any experiments. I focused more on laying the
  ground work for further research.
• Nevertheless, there were some obstacles to
  overcome...

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Main Issues

• The three main problems that I had to overcome in
  this research were
• Air sampling.
• Nanosensor type(s).
• Sensor placement.

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Solution Injecting air into liquid.
Figure 2.

• In order to inject air into a liquid I had to use
  a device called a wetted wall cyclone air
  collector.
• This device pneumatically draws in air and sprays
  it with a liquid (usually water). It then
  transfers a liquid on to whatever device one
  wants to pass it on to.

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Solution Type of nanosensor.
Figure 3.

• The type of nanosensor that I believe would work
  well with a device like this would be an
  electrical impedance based microfluidic
  biosensor. Much like the one Dr. Tung has
  developed.
• There would have to be many of these sensors,
  each programmed to detect a certain biological
  agent.

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Other type of nanosensor.Figure 4

• Yale's semiconducting nanowire nanosensor.
• These sensors are able to detect single virus
  particles or ultra-low concentrations of a
  targeted substance (Technology Review).
• These kinds of sensors are easy to make.
• Researchers are in the process of finding ways to
  mass produce these types of senors.

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Method of application.

• By putting the available technologies together in
  such a way that the air gets drawn in and
  scanned by the sensor, we will be able to create
  a true bioaerosol nanosensor that could be mass
  produced and put into service all around the
  world.
• All we would then have to do is write a program
  that evaluates the electrical signals of the
  sensor and activates the necessary procedures.

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Activation Procedure.

• Bioaerosol detected.
• Air filtration begins (slowly).
• Ventilation continues for 30 min.
• Filters would then be exchanged and the sensors
  inspected/ maintained.

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Available types of bioaerosol sensors.

• Other types of sensors that have been created to
  sense bioaerosols are
• MIT's PANTHER (PAthogen Notification for
  THreatening Environmental Releases).
• Livermore's APDS (Autonomous Pathogen Detection
  System).
• These types of sensors utilize genetically
  engineered material in order to detect the
  bioaerosols.

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Other types of bioaerosol sensorsPANTHER

• Utilizes genetically engineered B cells that
  react to pathogens by changing colors.
• This reaction is then monitored by a computer in
  order to determine what pathogen the B cells
  reacted to.

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Other types of bioaerosol sensors APDS

• Utilizes antibodies attached to dye coated
  microbeads.
• When the antibodies contact the pathogens they
  cause the dye to change colors.
• This color change is then observed by the
  computer.

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In conclusion...

• The ability to apply nanotechnology to HVAC
  systems is absolutely possible and could be made
  available in months, not years.
• All that is needed now is nanosensors that are
  specialized to detect minute particles of
  bioaerosols, the rest is just putting the pieces
  of the puzzle together.

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Citations

• Nanosensor. 7 May 2008. Wikipedia. 25 May 2008.
  lthttp//en.wikipedia.org/wiki/Nanosensorgt .
• Cantrell, William. Factors Affecting the Spread
  of a Bioterrorist Agent Through a Building.
  Research. U of Arkansas Fayetteville. 28 April
  2008.
• HVAC Systems and Components Handbook (2nd
  Edition). Automatic Temperature, Pressure, Flow
  Control Systems. Retrieved June 5, 2008, from Dr.
  Darin Nutter.
• (Figure 2, PANTHER APDS)Petrovick, Martha S.
  (2007). Rapid Sensors for Biological-Agent
  Identification, 17(1), 21. Retrieved June 30,
  2008, from www.ll.mit.edu/publications/journal/pdf
  /vol17_no1/17_1_3Petrovick.pdf.
• (Figure 3)Srinivasan, Balaji. Tung, Steve.
  (2006). Simulation of an Electrical Impedance
  Based Microfluidic Biosensor for Detection of E.
  coli cells. COMSOL Users Conference, 1-5.

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Citations

• (Figure 1) http//img.dailymail.co.uk/i/pix/2007/
  07_02/NYshoesREX_468x624.jpg
• (Figure 4, Technology Review) Bullis, K. 2007.
  Easy-to-Make Nanosensors. Tiny electronics-based
  detectors could provide simple tests for cancer
  or bioterror agents. Technology Review. January
  31, 2007, lthttp//www.technologyreview.com/Nanotec
  h/18127/?afgt.
• McDowall, Robert. 2006. Fundamentals of HVAC
  Systems. Elsevier, Oxford, UK.