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Displaying 576 - 600 of 1856

Interface-State Capture Kinetics by Variable Duty Cycle Charge Pumping

April 27, 2015
Author(s)
Asahiko Matsuda, Jason T. Ryan, Jason P. Campbell, Kin P. Cheung
We demonstrated a new variant of the charge-pumping technique featuring varying duty cycle gate pulses to directly probe the interface-state carrier capture process in the time domain. This technique retains the exceptional sensitivity of charge pumping

Nondestructive measurement of the evolution of layer-specific mechanical properties in sub-10nm bilayer films

April 21, 2015
Author(s)
Justin M. Shaw, Kathleen Hoogeboom-Pot, Jorge Hernandez-Charpak, Henry Kapteyn, Margaret Murnane, Damiano Nardi
ABSTRACT: We use short-wavelength extreme-ultraviolet light to independently measure the mechanical properties of disparate layers within a bilayer film with single-monolayer sensitivity. We show that in Ni/Ta nanostructured systems, while their densities

Interface-State Capture Cross Section — Why Does It Vary So Much?

April 20, 2015
Author(s)
Jason T. Ryan, Asahiko Matsuda, Jason P. Campbell, Kin P. Cheung
A capture cross section value is often assigned to Si-SiO2 interface defects. Using a kinetic variation of the charge pumping technique and transition state theory, we show that the value of capture cross section is extremely sensitive to the measurement

The Nature of Record Efficiency Fluid-Processed Nanotube-Silicon Heterojunctions

April 20, 2015
Author(s)
Jeffrey A. Fagan, Erik K. Hobbie, John M. Harris, Matthew R. Semler
The dark transport characteristics of heterojunctions assembled from type, chirality and length-purified single-wall carbon nanotubes (SWCNTs) are used to clarify the nature of nanotube-silicon diodes and solar cells. The freestanding films show remarkable

How Large Can We Go? Isolation of > 1 nm Diameter Single-Wall Carbon Nanotubes Species using Aqueous Two Phase Extraction

April 14, 2015
Author(s)
Jeffrey A. Fagan, Erik Haroz, Rachelle Ihly, Hui Gui, Jeffrey Blackburn, Jeffrey R. Simpson, Stephen K. Doorn, Stephanie Lam, Angela R. Hight Walker, Ming Zheng
We demonstrate the effective separation of near-monochiral single-wall carbon nanotube (SWCNT) species with diameters > 1 nm through multi-stage aqueous two phase extraction (ATPE), and report an empirical function for the surfactant concentrations at

Direct correlation of charge transfer absorption with molecular donor:acceptor interfacial area via photothermal deflection spectroscopy

April 9, 2015
Author(s)
Lee J. Richter, Dean M. DeLongchamp, Natalie Stingelin, Alberto Salleo, Martin Heeney, Aram Amassian, John deMello, James Bannock, Fiona H. Scholes, Scott Watkins, Zhuping Fei, Koen Vandewal
ABSTRACT: Here, we show that the Charge Transfer (CT) absorption signal in bulk (BHJ) solar cell blends, measured by photothermal deflection spectroscopy (PDS), is directly proportional to the density of molecular donor/acceptor interfaces. Since the

Model colloid system for interfacial sorption kinetics

March 24, 2015
Author(s)
Paul NMN Salipante, Steven D Hudson
Adsorption kinetics of nanometer scale molecules, such as proteins at interfaces, is usually determined through measurements of surface coverage. Their small size limits the ability to directly observe individual molecule behavior. Hence, the effect of

The Testing Program at NIST on Fibers Used in Soft Body Armor Applications

March 21, 2015
Author(s)
Walter G. McDonough, Amanda L. Forster, Jae Hyun Kim, Nathanael A. Heckert, Joy P. Dunkers, Scott A. Wight, Gale A. Holmes
The goal of this paper and presentation is to give an update of the research effort to date being conducted at the National Institute of Standards and Technology (NIST) on polymeric fibers used in soft body armor with a special emphasis on new fibers under

Preparation and Separation of DNA-Wrapped Carbon Nanotubes

March 18, 2015
Author(s)
Geyou Ao, Ming Zheng
Purification of single-chirality single-wall carbon nanotubes (SWCNTs)from their synthetic mixture is a prerequisite for many applications. DNA-controlled carbon nanotube (CNT) purification has evolved over a decade along with other separation techniques

Redox sorting of carbon nanotubes

March 17, 2015
Author(s)
Hui Gui, Jason K. Streit, Jeffrey Fagan, Angela R. Hight Walker, Chongwu Zhou, Ming Zheng
This work expands the redox chemistry of single-wall carbon nanotube (SWCNT) by investigating its role in a number of SWCNT sorting processes. Using a polyethylene glycol (PEG)/dextran (DX) aqueous two-phase system, we show that electron-transfer reaction

Beam broadening in transmission EBSD

March 16, 2015
Author(s)
Robert R. Keller, Katherine P. Rice, Mark Stoykovich
Transmission electron backscatter diffraction (t-EBSD), also known as transmission electron forward scatter diffraction (t-EFSD) or transmission Kikuchi diffraction in the SEM (TKD-SEM), can provide significant improvements in spatial resolution over

IMPACT OF ENVIRONMENTAL FACTORS ON POLYMERIC FILMS USED IN PROTECTIVE GLAZING SYSTEMS

March 11, 2015
Author(s)
Christopher C. White, Kar T. Tan, Donald L. Hunston, Aaron M. Forster, Deborah S. Jacobs
Accelerated and natural aging of safety films used in protective glazing systems was investigated by the use of Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible spectroscopy and tensile tests. Accelerated conditions involved simultaneous

Frequency Modulated Charge Pumping with Extremely High Gate Leakage

February 13, 2015
Author(s)
Jason T. Ryan, Jibin Zou, Jason P. Campbell, Richard Southwick, Kin P. Cheung, Anthony Oates, Rue Huang
Charge pumping (CP) has proven itself as one of the most utilitarian methods to quantify defects in metal-oxide-semiconductor devices. In the presence of low to moderate gate leakage, CP quantification is most often implemented via a series of measurements

Reducing Block Copolymer Interfacial Widths through Polymer Additives

February 10, 2015
Author(s)
Daniel F. Sunday, Regis J. Kline
There is a need to design new materials to achieve smaller pitches and reduced interfacial widths for use in the nanopatterning of block copolymers (BCPs). One option is the use of blends, where the addition of a homopolymer which selectively associates to

Critical Examination of the Colloidal Particle Model of Globular Proteins

February 3, 2015
Author(s)
Prasad S. Sarangapani, Steven D Hudson, Ronald L. Jones, Jack F. Douglas, Jai A. Pathak
Recent studies of globular protein solutions have uniformly adopted a colloidal view of proteins as particles, a perspective that neglects the polymeric primary structure of these biological macromolecules, their intrinsic flexibility and their ability to
Displaying 576 - 600 of 1856