Man and the Environment: P6 Victorious Group 3

1. Man and the Environment: P6 Victorious Group 3

2. What is nanotechnology? Extra info: A nanometre is a billionth of a metre. That’s half of the diameter of a strand of DNA! • The engineering of functional systems at the molecular scale • Building machines on the scale of molecules – a few nanometres wide • Involves the controlling and restructuring matter at the nanoscale • Endless possibilities regarding its uses

3. The 4 generations of nanotechnology 2000 2005 2010 2015-2020

4. How does nanotechnology work? • Quantum mechanics play a very important role in nanotechnology • Quantum physics is different from classical physics as substances at the nanoscale can behave erratically from what was expected • For example: • An electron can teleport—this is called electron tunneling • Substances that are insulators can become semi-conductors at the nanoscale • We can manipulate substances at the nanoscale to use them in various applications

5. How Nanotechnology Impacts Us

6. How Nanotechnology Impacts Us Fabric Nanowhisker • 10nm long, made of carbon atoms • Causes water to bead up instead of being absorbed • Makes fabric water and stain resistant Silver Nanoparticles Nanopores Inspiration Peaches, water lotus and many other plants have fine hair that cause water to bead up on their skin. • Silver has antimicrobial and antibacterial properties. • Infusing silver nanoparticles with fabric threads creates odourless, antibacterial, and more-UV resistant-fabrics. • 20 to 30nm pores in fabric that are 100 times smaller than pores in conventional insulation • Smaller porosity, less heat escapes, better insulation • Gives more insulation with less material New future for insulation

7. Food Nanofilms: Allow food to stay fresh longer Nanosensors Silver nanoparticles • Use nanomaterials that enable sensitive detection of just a few pathogen (a micro-organism that causes disease in its host) particles in a sample • Cheap enough for widespread use in farms and packaging plants • Polyamide and metal nanofilms: Impermeable barrier to gases and moisture • Polyester and Polyolefin nanofilms: Retain the flexibility of packaging • Act as antibacterial coating that actively reduces the growth of harmful microbes • Other antimicrobial materials being investigated: Zinc oxide nanoparticles and chitin

8. How Nanotechnology Impacts Us Sporting Goods with without Silicon Nanoparticles Carbon Nanotubes Nanocomposite Film • Particles are closely packed, increasing density but not much weight. • Used to strengthen sporting goods without increasing weight. • Examples include fishing rods. • 2nm wide, molecules are bound together without breaks. • Much lighter than steel, but 52 times stronger due to consistent connections • Useful to make racquets, which need the frame to be strong yet light. • Nanocomposite film have reducs the amount of air escaping from the encapsulated object by using nanopores instead of conventional holes • Tennis balls can last longer if coated with this film

9. Batteries Nanograss Porous silicon nanoparticles Carbon nanotubes • Liquid droplets of electrolyte stay dormant atop nanograss until stimulated to flow, triggering a reaction producing electricity • Prevents low level discharge when there is no draw on the battery, increasing shelf life dramatically • Make up 1 layer of spray-painted battery when combined with carbon black particles • Enables almost any object to be converted to a battery • Hold 3 times as much energy as current lithium-ion batteries • Recharges within 10 minutes • Prevents cracking of the electrode which occurs in solid silicon electrodes

10. How Nanotechnology Impacts Us Medicine Insulin Nano-network Particles Anti-microbial Burn Dressing Magnetic Nanoparticles • Nanocapsules integrated into dressing release antibiotics when in contact with harmful bacteria and kills the bacteria • Does not harm good bacteria that helps healing but prevents infection • Nanocapsules also contain dye, which will dye the dressing red and alert doctors to take action • Can save many lives – bacterial infection that is not detected and treated early in burn victims can result in death • Kept in the bloodstream without blood obstruction via externally applied magnetic force around the body • Nanoparticles are coated with enzymes that break down in high glucose levels • When the enzyme coating breaks down, the insulin in the nanoparticle is released into the bloodstream • One injection of these particles can maintain blood sugar levels in Type 1 diabetes patients for a decent amount of time • Diabetes patients no longer have to constantly inject themselves with insulin • Coated with antibodies that target cancer cells • After the nanoparticles attach to cancer cells, they can be extracted through external magnetic attraction • Allows cancer cell extraction without harming other cells like chemotherapy)

11. Space Carbon nanotubes: Space elevator Nanosensors Bio-nano robots • Outer layer: Function separately from the astronaut’s spacesuit, fixing dangerous spacesuit issues like tears or ruptures • Inner layer: Operate inside the spacesuit, tending wounds or administering medication • Monitor the life support systems in spaceships • Ensure that trace chemicals and elements in the interior environment are at a safe level for passengers • Cables that are lightweight yet strong • Dramatically reduce the cost of sending things into orbit (space elevators do not involve the use of costly rockets and fuel!)

12. How Nanotechnology Impacts Us Electronics Nanoglue Nanowires Nanocrystals • Glue is less than a nanometer thin, 10 times thinner than current adhesives used to bind silica and metal in computer chips that are otherwise hard to bind. • Allows more efficient heat transmission • Easily applied – printed and stuck on the wafer slices in patterns • Made of copper, only 70 to 250 nm wide each. • The smaller the tip size of the nanowire, the stronger the electrons emitted – thus their pentagonal shape allows maximum electrodes emitted with minimum electrical power • With vast numbers of individual electron emitters rather than a single electron gun like in a old box television, plus their low power consumption, they can make sharper and brighter ultra-thin displays. • Normal amourphous silicon (currently used for circuits in displays) need over hundreds of degrees to integrate, but nanocrystals can be “coated” onto plastic at room temperature • This allows possibilities for flexible plastic as the backing, which would otherwise melt with the conventional way. • The circuit is more conductive being sandwiched in a thin layer of plastic, requiring less energy to power • The circuits are applied in layers that are separated with a thin layer of gold, which acts as a film for the electrodes to pass through

13. Chemical and Biological Sensors Clip-on nanosensors for mobile phones Semiconductor nanowire Gold nanorods • Detect cancer by identifying the proteins found on the exteriors of cancer cells • Scientists examine how the protein-nanorod combination scatters light in order to come up with precise diagnoses • Detect toxins in the air expelled when a person talks and alerts user when harmful substances are sensed • Indicates the presence of diseases such as diabetes and cancer • Detect a range of chemical vapours through changes in the conductance of nanowires • Amount and direction of the conductance change depends on the molecule detected

14. Effects of nanotechnology on the environment

15. Positive effects • -Better water quality • -How it helps Nanotechnology can help remove industrial water pollutants, such as a cleaning solvent called TCE(Trichloroethylene), from ground water. The iron nanoparticles disperse throughout the body of water and decompose the organic solvent in place. Nanoparticles can be used to convert the contaminating chemical through a chemical reaction to make it harmless. Studies have shown that this method can be used successfully to reach contaminates dispersed in underground ponds and at much lower cost than methods which require pumping the water out of the ground for treatment.

16. Better air quality • How it helps Air pollution can be remediated using nanotechnology in several ways. One is through the use of Nano-catalysts with increased surface area for gaseous reactions. Catalysts work by speeding up chemical reactions that transform harmful vapors from cars and industrial plants into harmless gases. One example of this is how researchers have demonstrated that the use of silver nanoclusters as catalysts can significantly reduce the polluting byproducts generated in the process used to manufacture propylene oxide. Propylene oxide is used to produce common materials such as plastics, paint and detergents.

17. Improved fuel cells • -How it helps Companies are using nanotechnology to create more efficient membranes; this will allow them to build lighter weight and longer lasting fuel cells. Researcher have demonstrated that an array of nanowires embedded in a polymer results in low cost but high efficiency solar cells. This, or other efforts using nanotechnology to improve solar cells, may result in solar cells that generate electricity as cost effectively as coal or oil.

18. Negative effects • -Human Health Nanoparticles are so small that they can easily penetrate living cells. The human body is designed to detect foreign objects and produce phagocytes to break down the foreign object. However, if the body's phagocytes are constantly digesting nanoparticles, the cells cannot break down bacteria or other debris inside the body. Another study by toxicologist Eva Oberdorster from Southern Methodist University involved exposing captive large-mouth bass to various levels of carbon-60, or buckminsterfullerene. She discovered an immune response in the livers of the fish population two days later. This reveals that the small nanoparticles were able to bypass the fishes' immune systems, thereby raising the concerns that they could also do the same to the human immune system and harm the body.