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CLT Exemplars Visualization for Active learning: Understanding Nanomachines By Adham Ramadan Department of Chemistry Flash animations by Reham Tallawi.

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Presentation on theme: "CLT Exemplars Visualization for Active learning: Understanding Nanomachines By Adham Ramadan Department of Chemistry Flash animations by Reham Tallawi."— Presentation transcript:

1 CLT Exemplars Visualization for Active learning: Understanding Nanomachines By Adham Ramadan Department of Chemistry Flash animations by Reham Tallawi CLT

2 Scope Nano science and technology is one of the most rapidly developing areas in scientific research today. A particular interest within this area is concerned with nano machines. However, the notion of how they operate can be challenging to conceptualize, particularly with regards to their motion. Visual learning objects can be very useful in this regard.

3 The Nano" Dimension Nano meter = meter = mm i.e. a 1/1,000,000 of a mm A human hair is m (10,000 nm) thick

4 The Nano" Dimension

5 Time Line 4 th century 1661 Roman glass containing nano metallic clusters Boyle suggests the existence of corpuscles minute masses / clusters that are not easily dissipable into particles that compose them 18 th & 19 th centuries Development of photography based on emulsions of silver halides, with photochemical reactions resulting in Ag nanoparticles composing the pixels of the image 1908 Mie publishes a paper explaining the dependence of glass colour on metallic clusters size and type 1950s 1970s 1990s 1960s 1980s 1950s & 1960s: Experimental activities on inorganic nano particles 1960: Feymans lecture to the American Physical Society speculating on possibilities & potentials of nano sized materials 1970s: Fabrication of 2D quantum wells at Bell and IBM labs 1980s: Fabrication of metallic clusters using laser in 1981 Synthesis of Fullerene in 1985 Development of 1 st nanomachine Development of techniques for synthesizing and observing nanostructures (laser techniques, electron beam lithography, STM) Observing of some of the special properties of nanoparticles 1990s: Fabrication CNTs Discovering superconductivity & ferromagnetism in C 60 structures Growing research in self assemblies Widespread use of STM and AFM Research in inkjet lithography Mid 1990s: Widespread recognition of full potential of nanotechnology and realization of its interdisciplinary nature

6 Nanomachines A machine is an assembly of interconnected components arranged to transmit or modify force to perform useful work Collins English Dictionary A nanomachine is one which does that on the nano dimension

7 Nanomachines: What they are not!

8 Nanomachines: What they are Nanomachines are atomic and molecular assemblies which have been constructed to perform organized work/motion at the nano- scale, which is analogous to that on the macro-scale. Ellenbogen J.C., Love J.C. in Handbook of nanoscience and Technology, Goddard W.A., Brenner D.W., Lyskevski S.E., Lafrate G.J., eds, CRC Press, 2002, Vicario J., Meestma A., Feringa B.L., Chem. Comm., 2005,

9 They represent a scientific curiosity and and experimental challenge at this development phase. Possible immediate applications: –Medial technology: diagnosis as well as targeted drug delivery –Sensor technology: toxicological sensors Envisaged future applications: –Bottom-up building of novel devices: used as components for building more ellaborate devices on these small scales. Nanomachines why are they so exciting?

10 Nanomachines Reporting on their motion This is usually carried out in publications through textual descriptions + 2 D diagrams. This is effective in relaying information about WHAT LEADS to their motion. However it is not effective in relaying a clear picture of the actual motion.

11 Examples Self-propelled nanorods: a nano-submarine Nano-rods of Platinum and gold. Catalytic decomposition of hydrogen peroxide to generate oxygen gas on the Pt side causes the motion, pushing the platinum part forward. Motion is due to the change in polarity of the liquid around the nano-rod and the interaction of the gold surface with it. Nanorods movement paths Hydrogen peroxide Oxygen + Water (H 2 O 2 ) O 2 + H 2 O Paxton, W.F., Kistler, K.C., Olmeda, C.C., Sen, A., St. Agenlo, S.K., Cao, Y., Mallouk, T.E., Lammert, P.E., Cresi, V.H., J. Am. Chem. Soc., 2004, 126, Fournier-Bidoz, S., Arsenault, A.C., Manners, I., Ozin, G.A., Chem. Commun., 2005,

12 Examples A nano bio-machine: a nano-locomotive Kinesin is a motor protein which can move along filamentous structures called microtubules. Kinesin has two head which alternately undergo a chemical reaction that releases them, then re-attaches them to the microtubule. Kinesin is fixed to a glass surface with its heads pointing upward. A microtubule can then move on these heads due to the chemical reaction. The microtubule carries enzymes which generate the chemicals needed for the reaction, i.e. a source for its own fuel. Vale, R.D., Milligan, R.A., Science, 2000, 288, Du, Y.Z., Hiratsuka, Y., Taira, S., Eguchi, M., Uyeda, T.Q.P., Ymoto, N., Kodaka, M., Chem. Comm., 2005,

13 Examples The nano-car These are single organic molecules synthesized with 4 bucky balls (C 60 ). When placed on a gold surface, and heated, the C 60 roll on the surface The bucky balls move independently, allowing the turning and pivoting of the nano-car. Real images of a nano car moving Shirai, Y., Osgood, A.J., Zhao, T., Kelly, K.F., Tour, J.M., Nano Lett., 2005, 5,

14 Understanding Nanomachines in Motion I Feedback

15 Examples (Again!) Self-propelled nanorods: a nano-submarine Nano-rods of Platinum and gold. Catalytic decomposition of hydrogen peroxide to generate oxygen gas on the Pt side causes the motion, pushing the platinum part forward. Motion is due to the change in polarity of the liquid around the nano-rod and the interaction of the gold surface with it.

16 Examples (Again!) Self-propelled nanorods: a nano-submarine

17 Examples (Again!) A nano bio-machine: a nano-locomotive Kinesin is a motor protein which can move along filamentous structures called microtubules. Kinesin has two head which alternately undergo a chemical reaction that releases them, then re-attaches them to the microtubule. An Animated Model for Processive Motility by Conventional Kinesin, Vale, R.D., Milligan, R.A., Johnson, G.,

18 Examples (Again!) A nano bio-machine: a nano-locomotive Kinesin is fixed to a glass surface with its heads pointing upward. A microtubule can then move on these heads due to the chemical reaction. The microtubule carries enzymes which generate the chemicals needed for the reaction, i.e. a source for its own fuel.

19 Examples (Again!) The nano-car These are single organic molecules synthesized with 4 bucky balls (C 60 ). When placed on a gold surface, and heated, the C 60 roll on the surface The bucky balls move independently, allowing the turning and pivoting of the nano-car.

20 Examples (Again!) The nano-car

21 Understanding Nanomachines in Motion II Feedback

22 Student Feedback Animations, as visual learning objects, are very useful for demonstrating movement. They are best as complementing text or narrative explanation. They are most useful for complex cases difficult to demonstrate using 2D diagrams and textual description. They are most effective as learning objects when offered after the challenge of textual description and 2 D diagrams. In these cases they are effective because they clarify ambiguities and/or confirm ideas. They are useful for group learning as they ensure that all develop a similar understanding. They have the drawback of possibly being limiting to the imagination.

23 Conclusions

24 Sources for images (in order of appearance in slides) mlhttp://www.brooklyn.cuny.edu/bc/ahp/LAD/C4c/C4c_carbon_forms.ht ml S/k2300_elect.htm&fronthttp://www.wfrfire.com/website/front/index.htm?/website/rescue/SAW S/k2300_elect.htm&front nt/electricFan.asphttp://www.empcorp.com/html/products/advanced/thermalManageme nt/electricFan.asp


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