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Mark Reeves
George Washington University
Research Teaching Group |
- Self assembly of nanoparticles
We have developed a technique, surface vertical deposition whereby colloidal particles can be deposited as films or in straight-line geometries as wires. This allows for the simple creation of arrays of parallel or crossing wires as described in the papers below. Our current efforts focus on the detection of proteins by the use of self-assembled nanoparticle wires [Supported by NRL]- J.J. Diao, Jianwei Sun, J.B. Hutchison, M.E. Reeves,
Self assembled nanoparticle wires by discontinuous vertical colloidal deposition
Appl. Phys. Letts. 87, 103113, (2005).. [PDF]
- J.J. Diao, J.B. Hutchison, Guanghong Luo, and M.E. Reeves,
Theoretical analysis of evaporation-driven colloidal deposition
J. Chem. Phys. 122, 184710 (2005).. [PDF]
- J.J. Diao, Shuogang Huang, M.E. Reeves,
Cavity Resonators of Metal-coated Dielectric Nanorods
J. Chem. Phys. 122, (2005).. [PDF]
- J J Diao, F S Qiu, G D Chen and M E Reeves,
Surface vertical deposition for gold nanoparticle film
J. Phys. D: Appl. Phys. 36, L25 (2003). [PDF]
- Quantitative, sub-micron microwave microscopy
The development of evanescent mode microscopy has allowed the detailed study of the spatial variation of the dielectric constant in bulk and thin-film materials at length scales (~200 nm) much less that the probing wavelength (~16 cm). By comparing precise measurements with accurate finite-element calculations, we are able to correlate the sample topography and microstructure with the dielectric response. These results test our understanding of inhomogeneity, microstructure, and anisotropy on the high-frequency properties. Thus sample preparation conditions can be carefully altered to make materials better suited to wireless applications. [Supported by DARPA, ARO]
- H. M. Christen, G. E. Jellison, Jr., I. Ohkubo, S. Huang, M. E. Reeves, E. Cicerrella, J. L. Freeouf, Y. Jia, and D. G. Schlom
Dielectric and optical properties of epitaxial rare-earth scandate films and their crystallization behavior
Appl. Phys. Letts. 88, 262906 (2006). . [PDF]
- T. Izuhara, I.-L. Gheorma, R. M. Osgood, Jr. , A. N. Roy, H. Bakhru, Yiheli M. Tesfu, and M. E. Reeves,
Single-crystal barium titanate thin films by ion slicing
Applied Physics Letters, 82, 616, (2003). [PDF]
- T. Izuhara, R. M. Osgood, Jr. , M. Levy, M. E. Reeves, Y. G. Wang, A. N. Roy, and H. Bakhru,
Low-loss crystal-ion-sliced single-crystal potassium tantalate films
Applied Physics Letters, 80, 1046, (2002). [PDF]
- Y.G. Wang, M.E. Reeves, W.J. Kim, J.S. Horwitz, and F.J. Rachford,
Uniaxial dielectric anisotropy in Ba0.5Sr0.5TiO3 films studied by evanescent-probe microscopy
Applied Physics Letters, 78, 3872, (2001). [PDF]
- Y.G. Wang, M. E. Reeves, F.S. Rachford,
Simultaneous imaging of dielectric properties and topography in a PbTiO3 crystal by nearfield scanning microwave microscopy
Applied Physics Letters, 76, p 3295 (2000). [PDF].
- Y.G. Wang, M. E. Reeves, W. Chang, J.S. Horwitz, and W. Kim,
Near-field imaging of the microwave dielectric properties of single-crystal PbTiO3 and thin-film Sr(1- x)BaxTiO3
Mat. Res. Soc. Proc., 603, 289 (2000). [PDF]
- Phase diagrams in flux matter
Measurements of the pressure dependence of the irreversibility line are used to elucidate the effect of anisotropy on the formation of flux lines in anisotropic superconductors. More recently, spatially- resolved, Hall-array measurements have shown the effect of the glass transition and melting on the critical currents in high-temperature superconductors.[Supported by NRL]- M. P. Raphael, M. E. Reeves, E. F.Skelton, C. Kendziora,
Pressure Dependence of the Irreversibility Line in Bi2Sr2CaCu2O8+x
IEEE Transactions on Applied Superconductivity, 1, March 2001, pp.3951 (2001) [PDF].
- M. P. Raphael, M. E. Reeves, E. F.Skelton, C. Kendziora,
Pressure Dependence of the Irreversibility Line in Bi2Sr2CaCu2O8+x: Role of Anisotropy in Flux- Line Formation,
Phys. Rev. Letts. 84, 1587 (2000). [PDF]
- M. P. Raphael, M. E. Reeves, E. F.Skelton, C. Kendziora,
Pressure Dependence of flux dynamics in High temperature Superconductors
AIP Conference Proceedings 483, p. 314 (1999). [PDF]
- M. P. Raphael, M. E. Reeves, and E. F.Skelton,
Nonlinear Response of Type II Superconductors: A New Method of Measuring the Pressure Dependence of the Transition Temperature, Tc(P)
Rev. Sci. Instrum. 69, 1451-5 (1998). [PDF]
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- Changes in surface chemistry induced by kidney dialyzer reuse
The manufactor of polymeric materials for kidney dialyzer membranes has resulted in a significant increase in biocompatibility. This is coupled with a need to reuse dialyzers as many as 15 to 20 times before their eventual disposal. However, widespread reuse has led to the occurance of adverse patient reactions, probably due to the release of proteins, triggered by increase of positively charged regions on the membrane surface. We are studying these changes globally by measurements of the zeta potential and bradykinin release for dialyzers in clinical settings. These data are correllated to microscopic atomic and chemical force microscopy data, which demonstrate structural and surface chemical changes on a microscopic scale. [Supported by the National Kidney Foundation]
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- F/2007: Phys 801, Dean's Seminar; Biochemistry on the Head of a Pin
- F/2007: PSMB 261, Physics of Biotechnology
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