Docstoc

Slide 1 - National Science Foundation

Document Sample
Slide 1 - National Science Foundation Powered By Docstoc
					 Complex Fluids with Extended, Rigid Components
 Paul S. Russo, Louisiana State University, DMR-0075810
Gold nanoparticles formed in PNIPAM gel                                                      Bootstrap DLS analysis
Graduate student Jirun Sun                                                                   Postdoctoral associate Grigor Bantchev
                                                                                                                                                                                 Our uniquely efficient,
 UV-vis absorbance follows particle growth.                                                                 1500
                                                                                                                                                                                 multi-angle, multi-
                                                                                                                                                                                 correlator DLS device
                                                                At ~ 525 nm the surface                     1000
                                                                                                                                                                                 compares well with a
                      0.2
                                                                plasmon band of the gold




                                                                                                  -1
                                                                                                                                              25




                                                                                                  MA / s
                                                     3 hour
                                                                                                                                              20
                                                                                                                                                                                 conventional instrument,
                                                                nanoparticles shows that
                                                     1.5 hour
                                                                                                                                                                                 down to a very low 6 Hz.
                                                                                                                                              15
   Absorbance /a.u.




                                                                                                            500
                                                     1 hour
                                                     0.5 hour
                                                                formation is finished in                                                      10


                                                                                                                                              5


                                                                about 3 hours. The average                    0
                                                                                                                       4 points               0
                                                                                                                                                   0   5   10   15     20   25


                                                                diameter of the gold
                      0.1                                                                                          0        500         1000                    1500
                                                                                                                                          -1
                                                                                                                                  Conv / s

                                                                nanoparticles is 20 nm.
                                                                                                                  kT
                                                                                             D trans             6 R   4             3 D trans
                                                                                                                         R 2 R 
                      0.0
                            400   500        600          700       800
                                                                                                              
                                        Wavelength /nm
                                                                                              D rot               kT     3             4 D rot
                                                                                                                      3
                                                                                                                8 R
               Pink gel at right contains nanogold.                                                                             kT              kT
                                                                                                                                      
                                                                                                                              8R 3D rot 6RD trans
                                                         For the first time, the gold
                                                         nanoparticles are formed            Something new in Stokes-Einstein: the size of optically anisotropic
                                                         inside a standing gel by            particles can be determined without prior knowledge of the
                                                         reduction of a self-                viscosity! Once size is in hand, the Stokes-Einstein relations can be
                                                         assembled, temporary                inverted to estimate the viscosity. This can be useful to size
                                                                                             particles in aggregating systems, or to obtain the viscosity of
                                                         scaffold.                           complex fluids or polymers in supercritical fluids.
Complex Fluids with Extended, Rigid Components
Paul S. Russo, Louisiana State University, DMR-0075810
                                              Education
                                              Ph.D. Degree & Current Career Choice
  Outreach                                    Jirun Sun (postdoc at NIST)
                                              Graduate Students This Grant Supports
                                               Erick Soto-Cantu (Mexico); Jian Qiu (China);
                                              Derek Dorman (Mississippi)
                                              Undergrads & Current Location
                                               Pavan Bellamkonda (graduate chemistry at Northwestern)
                                               Katie Vance (graduate pharmacy at Emory)

                                                Synergistic Activities, Paul S. Russo
                                                •Co-founder and member, Board of Directors, Louisiana
                                                Applied Polymer Technology Extension Consortium (APTEC),
                                                an inter-university one-stop-shopping economic development
                                                tool. Current interest: streamlining intellectual property to
   Graduate student Erick Soto-Cantu
                                                stem the tide of research being sent Europe and Asia.
   (left) judging an engineering project at
                                                •Member, Program Committee, Chemical Education
   a science & engineering fair at
                                                Foundation (Arlington, VA). Only academic on this panel.
   McKinley High School in Baton Rouge.
                                                •Co-advisor (with R. Strongin) of Student Affiliates of the
                                                American Chemical Society. Their achievements include the
                                                first-ever Louisiana chemistry summer day camp for high
               LSU Polymer Analysis             school students, solidified bylaws, an invited article in in
                                                Chemistry, the ACS magazine for undergraduates, and a
                                                student-authored website (http://macro.lsu.edu/saacs ), all
                                                culminating in designation as an Outstanding Chapter (the
                                                only one of 32 nationwide at a large university).

				
DOCUMENT INFO
Shared By:
Categories:
Tags:
Stats:
views:0
posted:3/2/2013
language:English
pages:2