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Molecular self-assembly often occurs in the presence of long chain polymers, and we develop a theory to describe the competition between self-assembly and phase separation that gen- erally occurs in these complex uids. The theory includes a description of
Plastics are ubiquitous in our modern world. It difficult to find a manufactured object that does not contain at least some sort polymeric (plastic) components. This ubiquity, in large part, reflects the ease with which polymers can be formed at low
We examine a broadband method to extract the relative permittivity and loss tangent of low-loss dielectric substrates from on-wafer scattering-parameter measurements of coplanar waveguides of differing lengths. To validate this method, we compare with
Vijay Tirumala, August W. Bosse, Eric K. Lin, Vikram Daga, Alvin Romang, Jan Ilavsky, J J. Watkins
The use of short chain block copolymer melts as nanostructured templates for sub-10 nm domains is often limited by their low segregation strength (N). Since increasing molar mass to strengthen segregation also increases the interdomain spacing of block
Virgil Percec, Mihai Peterca, Andres E. Dulcey, Mohammad Imam, Steven Hudson, Sami Nummelin, Peter Adelman, Paul A. Heiney
The synthesis of a library containing 12 conical dendrons that self-assemble into hollow spherical supramolecular dendrimers is reported. The design principles for this library were accessed by development of a method that allows the identification of
John M. Treinen, Philippe P. Darcis, Joseph D. McColskey, R. Smith, J. Merritt
In this study, the effect of specimen geometry on the fatigue crack growth rates (FCGR) in API X65 and X100 pipeline steels was explored using the middle tension and compact tension specimen geometries. It was found that the specimen type has little
Katie Hurst, Anne Dillon, Shao Yang, John H. Lehman
We investigate the purification of as-prepared single wall carbon nanotubes (SWCNTs) by exposure to pulsed 193 and 248 nm laser light, as well as lamp wavelengths of 254 and 185 nm. Raman spectroscopy before and after laser exposure indicates the removal
Fast-IDVG measurements have become an increasingly important tool to examine MOSFET transient degradation. The threshold voltage (VTH) extracted from fast-IDVG measurements is often used to infer the transient behavior of trapped charged in the gate
Nhan V. Nguyen, Oleg A. Kirillov, Weirong Jiang, Wenyong Wang, John S. Suehle, P. D. Ye, Y. Xuan, N. Goel, Kwang-Woo Choi, Wilman Tsai
In this letter we report the band offsets of the Al/Al2O3/GaAs structure determined by internal photoemission and spectroscopic ellipsometry. The energy barrier height at the Al2O3 and sulfur-passivated GaAs interface is found to be 3.0 eV, which is
Mark A. Rice, P. M. Homier, Kendall Waters, Kristi S. Anseth
Chondrocytes were encapsulated in non-degrading and partially degrading PEG gels in apposition to native cartilage layers in order to examine the effects of gel degradation on the integration of regenerated cartilaginous matrix with native tissue. In
The uncontrolled aggregation of amorphous calcium phosphate (ACP) particulate fillers and their uneven distribution within polymer matrices can have adverse effects on the properties of ACP composites. In this paper we assessed the influence of non-ionic
The objective of this study was to elucidate the effect of chemical structure and composition of the polymer matrix on the degree of vinyl conversion (DC) of copolymers (unfilled resins) and their amorphous calcium phosphate (ACP) composites attained upon
Kavita M. Jeerage, Tammy L. Oreskovic, Nikki S. Rentz, Damian S. Lauria
Based on its standard reduction potential, oxidized ferrocenemethanol (FcCH2OH+) may act as an alternate electron acceptor to oxygen during cellular metabolism. By locally oxidizing ferrocenemethanol (FcCH2OH) at a microelectrode, we probed the metabolic
Roni Reuven, Christopher N. McCowan, Elizabeth S. Drexler, Avigdor Shtechman, Philippe P. Darcis, John M. Treinen, R. Smith, J. Merritt, Thomas A. Siewert, Joseph D. McColskey
The toughness and plasticity of steel generally decreases with increasing testing rate. The crack tip opening angle (CTOA) was measured on two types of commercial pipeline steels, API-X65 and API-X100 at a range of displacement rates to characterize rate
Avigdor Shtechman, Christopher N. McCowan, Roni Reuven, Elizabeth S. Drexler, Philippe P. Darcis, John M. Treinen, R. Smith, J. Merritt, Thomas A. Siewert, Joseph D. McColskey
When a crack initiates and propagates in a pressurized pipe the only thing that might stop this high-velocity event is the release of internal pressure (decompression) resulting in a deceleration in the crack-propagation rate. This deceleration can be
Justin N. O'Donnell, Sarah Langhorst, Michael D. Fow, Joseph M. Antonucci, Drago Skrtic
This study explores how resin type affects selected physicochemical properties of complex methacrylate copolymers and their amorphous calcium phosphate (ACP)-filled and glass-filled composites. Two series of photo-polymerizable resin matrices were
Joannie W. Chin, Donald L. Hunston, Aaron M. Forster, Justin M. Ocel, Jean M. Hartmann, Paul Fuchs
Epoxies are increasingly used in construction for structural applications and properties such as creep are very important. For this reason, the thermo-viscoelastic properties and creep response of two commercial, ambient cure structural epoxy adhesives
The Materials Science &Technology 2008 Conference & Exhibition took place in the David L. Lawrence Convention Center in Pittsburgh, Pennsylvania from October 5-9. The MS&T 2008 Conference was a great success, with a total more than 1000 papers presented in
Vijay Tirumala, Sanghun Lee, Taiki Tominaga, Eric K. Lin, Jian P. Gong, Paul D. Butler, Wen-Li Wu
A molecular mechanism is proposed for the toughness enhancement observed in double network (DN) hydrogels prepared from poly (2 acrylamido, 2-methyl, 1-propanesulfonicacid) (PAMPS) polyelectrolyte network and polyacrylamide (PAAm) linear polymer. It is an
The system of programs described in this paper is concerned with estimating the damage ensuing from exposure of specimens in dry and humid atmospheres to UV and visible radiation covering the solar range. Damage is monitored quantitatively by changes in IR
Joannie W. Chin, Sylvain H. Petit, Amanda L. Forster, Kirk D. Rice, Michael A. Riley
During routine field use of soft body armor, the ballistic panels often become saturated with perspiration. This unsavory condition motivates the user to clean and/or deodorize the armor, and anecdotal evidence is given for various methods used to
Internal photoemission (IPE) spectroscopy is a powerful technique for investigating electronic properties at solid-solid interfaces. Upon photon excitation, electrons or/and holes in the solid under an external electrical bias, accumulate at the interface
Thomas A. Siewert, Michael Else, Richard J. Fields, Joe C. Bowles, L. J. Moore, Philip D. Flenner, Mario Macia, Jerry Rau, Steven E. Powell
The Pipeline and Hazardous Materials Safety Administration s (PHMSA) Pipeline Safety Research and Development (R&D) Program held its first structured peer review of active research projects in February 2006 and the most recent peer review on May 2008. The
Richard J. Fields, Louis E. Hayden, Thomas J. O'Grady, Joseph D. McColskey, Joe C. Bowles, T. R. Webb, Christopher N. McCowan, Dennis W. Hinnah, Ronald W. Haupt, Thomas A. Siewert
The purpose of this document is to report findings from the research peer reviews held March 27-29, 2007 for PHMSA's Pipeline Safety Research and Development Program. The findings and recommendations in this report derive from the scoring and comments