ECE5320 Mechatronics Assignment#01: Literature Survey on Sensors and Actuators Topic: Molecular MotorOutlineReference listTo explore further (survival pointers of web references etc)Major applicationsBasic working principle illustratedSlide 7Slide 8Slide 9Slide 10Slide 11Slide 12Slide 13Slide 14Slide 15Slide 16Slide 17Slide 18Slide 19Slide 20Slide 21LimitationsECE5320 MechatronicsAssignment#01: Literature Survey on Sensors and Actuators Assignment#01: Literature Survey on Sensors and Actuators Topic: Molecular MotorPrepared by:Joseph ThomasDept. of Electrical and Computer Engineering Utah State UniversityE: (435)757-7962 ; T: (435)797-; F: (435)797-3054 (ECE Dept.)3/6/200901/14/19ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuatorsSlide-2Outline –Reference list–To probe further–Major applications–Basic working principle illustrated–A typical sample configuration in application (application notes)–Limitations01/14/19ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuatorsSlide-3Reference list•A Reversible, Unidirectional Molecular Rotary Motor Driven by Chemical EnergyStephen P. Fletcher, Frédéric Dumur, Michael M. Pollard, and Ben L. Feringa (7 October 2005) Science 310 (5745) •Nanoscale Rotary Motors Driven by Electron Tunneling Boyang Wang, Lela Vukovic, and Petr Kral, Phys. Rev. Lett. 101, 186808 (2008) •Chemically Tunable Nanoscale Propellers of Liquids Boyang Wang and Petr Kral, Phys. Rev. Lett. 98, 266102 (2007)01/14/19ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuatorsSlide-4To explore further (survival pointers of web references etc) •http://www.chemistry.illinois.edu/research/organic/seminar_extracts/2002_2003/Quinn.pdf •http://www.sciencemag.org/cgi/content/abstract/310/5745/80 •http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=JCPSA6000123000018184702000001&idtype=cvips&gifs=yes01/14/19ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuatorsSlide-5Major applications •The assembly of a molecular propeller and a molecular motor can form a nanoscale machine that can pump fluids or perform locomotion. Future applications of these nanosystems range from novel analytical tools in physics and chemistry, drug delivery and gene therapy in biology and medicine, advanced nanofluidic lab-on-a-chip techniques, to tiny robots performing various activities at the nanoscale or microscale.01/14/19ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuatorsSlide-6Basic working principle illustratedChemically driven rotary molecular motors01/14/19ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuatorsSlide-7Basic working principle illustratedChemically driven rotary molecular motors The system is made up from a three-bladed triptycene rotor and a helicene, and is capable of performing a unidirectional 120° rotation.This rotation takes place in five steps. First, the amine group present on the triptycene moiety is converted to an isocyanate group by condensation with a phosgene molecule (a). Thermal or spontaneous rotation around the central bond then brings the isocyanate group in proximity of the hydroxyl group located on the helicene moiety (b), thereby allowing these two groups to react with each other (c).Basic working principle illustratedChemically driven rotary molecular motors This reaction irreversibly traps the system as a strained cyclicurethane that is higher in energy and thus energetically closer to the rotational energy barrier than the original state. Further rotation of the triptycene moiety therefore requires only a relatively small amount of thermal activation in order to overcome this barrier, thereby releasing the strain (d). Finally, cleavage of the urethane group restores the amine and alcoholfunctionalities of the molecule (e).01/14/19ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuatorsSlide-801/14/19ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuatorsSlide-9Basic working principle illustratedLight-driven rotary molecular motors01/14/19ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuatorsSlide-10Basic working principle illustratedLight-driven rotary molecular motors The 360° molecular motor system consists of a bis-helicene connected by an alkene double bond displaying axial chirality and having two stereocenters.One cycle of unidirectional rotation takes 4 reaction steps. The first step is a low temperature endothermic photoisomerization of the trans (P,P) isomer 1 to the cis (M,M) 2 where P stands for the right-handed helix and M for the left-handed helix. In this process, the two axial methyl groups are converted into two less sterically favorable equatorial methyl groups.01/14/19ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuatorsSlide-11Basic working principle illustratedLight-driven rotary molecular motors By increasing the temperature to 20 °C these methyl groups convert back exothermally to the (P,P) cis axial groups (3) in a helix inversion. Because the axial isomer is more stable than the equatorial isomer, reverse rotation is blocked. A second photoisomerization converts (P,P) cis 3 into (M,M) trans 4, again with accompanying formation of sterically unfavorable equatorial methyl groups. A thermal isomerization process at 60 °C closes the 360° cycle back to the axial positions.01/14/19ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuatorsSlide-12Basic working principle illustratedLight-driven rotary molecular motors01/14/19ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuatorsSlide-13Basic working principle illustratedLight-driven rotary molecular motors Another example of synthetic chemically driven rotary molecular motor that has been reported in literature make use of the stereoselective ring opening of a racemic biaryl lactone by the use of chiral reagents, which results in a directed 90° rotation of one aryl with respect to the other aryl. Feringa and co-workers used this approach in their design of a molecule that can repeatably perform 360° rotation. The full rotation of this molecular motor takes place in four different stages.01/14/19ECE5320 Mechatronics. Assignment#1 Survey on
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