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Virgil Percec, Mihai Peterca, Timur Tadjiev, Xiangbing Zeng, Goran Ungar, Pawaret Leowanawat, Emad Aqad, Mohammad Imam, Brad Rosen, Umit Akbey, Robert Graf, Sivakumar Sekharan, Daniel Sebastiani, Hans -. Spiess, Paul A. Heiney, Steven Hudson
The synthesis of perylene 3,4:9,10-tetracarboxylic acid bisimides (PBIs) dendronized with first generation dendrons containing 0 to 4 methylenic units (m) between the imide group and the dendron, (3,4,5)12G1-m-PBI, is reported. Structural analysis of their
A procedure is described for assigning values of the number of equivalent reference fluorophores (ERF) to microspheres labeled with a fluorophore designed to produce fluorescence in a given channel of a multicolor flow cytometer. There is a different
Behrang H. Hamadani, Nadine E. Gergel-Hackett, Paul M. Haney, Nikolai B. Zhitenev
We have studied the local charge transport properties of organic bulk heterojunction solar cells based on the blends of poly(3-hexylthiophene) (P3HT) and phenyl-C61-butyric acid methyl ester (PCBM) with a photoconductive atomic force microscope (PCAFM). We
Joseph T. Hodges, A. Cygan, Piotr Maslowski, Katarzyna E. Bielska, S. Wojtewicz, J. Domyslawska, Hisashi Abe, R.S. Trawinski, R. Ciurylo
We describe a high sensitivity and high spectral resolution laser absorption spectrometer based upon the frequency-stabilized cavity ring-down spectroscopy (FS-CRDS) technique. We used the Pound-Drever-Hall (PDH) method to lock the probe laser to the high
Vytautas Reipa, Jonghoon Choi, Nam S. Wang, Victoria M. Hitchins, Peter L. Goering, Robert Malinauskas
In anticipation of the increased use of various forms of silver as an antimicrobial agent in medical devices, the objective of this study was to evaluate the in vitro hemolytic potential of silver nanoparticles in dilute human blood, and to relate particle
Yvonne B. Gerbig, Stephan J. Stranick, Robert F. Cook
The theoretically-predicted anisotropic nature of the indentation phase transformation in silicon (Si) is observed directly in experiments using hyperspectral, confocal Raman microscopy. The anisotropy is reflected in the two-dimensional distribution of
Joshua A. Gordon, Christopher L. Holloway, James C. Booth, James R. Baker-Jarvis, David R. Novotny, Sung Kim, Yu Y. Wang
In this paper we demonstrate tunability of a metafilm, which is the two-dimensional equivalent of a metamaterial, also referred to as a metasurface, by changing the permittivity in a micro-fluidic channel that interacts with the metafilm. Numerical
Yvonne B. Gerbig, Linlin Ren, Lela Liu, Sanjit Bhowmick, Malvin Janal, Van Thompson, Yu Zhang
Porcelain veneered alumina crown restorations often fail from bulk fracture resulting from radial cracks that initiate at the cementation surface with repeated flexure of the stiffer crown layers on the soft dentin support. We hypothesize that bulk
Juan C. Collado Gomez, Eduard Rocas, Jordi Mateu, Nathan D. Orloff, James C. Booth, Alberto Padillo, Juan Callaghan
This work proposes a procedure to characterize the intrinsic nonlinearities of bulk acoustic wave resonators by performing one port measurements of the second harmonic and second order intermodulation spurious signals. Closed-form expressions have been
Carl G. Simon Jr., Kaushik Chatterjee, Limin Sun, Laurence C. Chow, Marian F. Young
Current methods for combinatorial and high-throughput (CHT) screening of cell-material interactions utilize a two-dimensional (2D) format where cells are presented on flat materials surfaces [1]. However, cell response in 3D scaffolds is more
Structural properties of polymeric scaffolds for tissue engineering play a key role in directing osteogenesis. These properties depend on the chemical nature and the fabrication process of biomaterial. There are many protocols for fabricating scaffolds for
Carl G. Simon Jr., Girish Kumar, Christopher K. Tison
Utilizing tissue scaffold architecture to induce stem cell differentiation is of tremendous importance to the regenerative medicine community. To this end, we have investigated the effect of nanofiber scaffold structure on primary human bone marrow stromal
Reference scaffolds characterized for cell response are being developed for use as a standard for biological characterization of new scaffolds. The need for reference scaffolds to serve as a calibration standard between labs has been identified as critical
Carl G. Simon Jr., Kaushik Chatterjee, Stevephen Hung
Protein adsorption mediates biological responses to materials. When a biodegradable polymer scaffold is placed in aqueous, physiological medium, proteins adsorb onto the scaffold surface. The total amount, composition and structure of the adsorbed protein
Oana Jurchescu, Brad Conrad, Christina Hacker, David J. Gundlach, Curt A. Richter
The fabrication of top metal contacts for organic electronics represents a challenge and has important consequences for electrical properties of such systems. We report a low cost and non-destructive printing process, Flip Chip Lamination (FCL), to
Peter M. Johnson, John A. Howarter, Christopher Stafford
In this work, we use constant load indentation and cantilever peel of polymer films to measure relaxation events due to the chemical modification of a buried interface. Hydroxypropyl cellulose films on four different chemical interfaces were produced, and
Carl G. Simon Jr., Kaushik Chatterjee, Sapun Parekh, Sheng Lin-Gibson, Nicole M. Moore, Marcus T. Cicerone, Marian F. Young
Cell functions such as proliferation, migration, and differentiation are key physiological processes that are influenced by the physiochemical extracellular environment. We report on the effect of three-dimensional (3D) scaffold modulus on human bone
Yeon S. Kim, Rick D. Davis, Jaime C. Grunlan, Amanda A. Cain
For the first time, Layer-by-layer (LbL) assemblies made with carbon nanofiber (CNFs) are shown to improve the fire performance of polyurethane foam. The (359 ± 36) nm thick four bilayer coating of polyethyleneimine/CNF (cationic layer) and poly(acrylic
In this talk I will 1) briefly review SEDs history of the optical thin metrology project, 2) describe the principle of internal photoemission (IPE) and the applications to determine the band alignments of metal-oxide-semiconductor structures, and 3)
Two selected members of the homologous series, An+2BBnO3n+3 (A= Sr, and Ca; B and B=Co) have been investigated for their crystal structure because of their potential applications as thermoelectric materials. A combined Rietveld refinement and a spin
Mingdong M. Li, Suvajyoti S. Guha, Rebecca A. Zangmeister, Michael J. Tarlov, Michael R. Zachariah
Electrospray (ES) sources are commonly used to introduce non-volatile materials (e.g. nanoparticles, proteins, etc.) in to the gas phase for characterization by mass spectrometry and ion mobility. Recent studies in our group using electrospray ion mobility
The 2010 Materials Research Society (MRS) Fall Meeting took place in the Hynes Convention Center and the Sheraton Boston Hotel, starting the weekend following the Thanksgiving Holidays from November 27 to December 3. This large-scale meeting included forty
We investigate a new kind of PVOH physical gel in which the volatile water is replaced with a non-volatile ionic liquid (IL). High melting IL containing Br- anion was chosen so that the hydrogen-bond accepting Br- can enhance miscibility with PVOH while
Xiaohong Gu, Somia Awad, Hongmin Chen, James Lee, E. Abdel-Hady, Y Jean
The free volume properties in a system of zinc oxide (ZnO) nanoparticles (20 nm) dispersed in waterborne polyurethane (WBPU) were measured using positron annihilation lifetime spectroscopy. Two glass-transition temperatures (Tg), lower Tg ~ 220 K and