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In recent work, a model for the structural environment of Hg bound to a catalytic DNA sensor was proposed on the basis of EXAFS data analysis. Although severely constrained by limited data quality and scant supporting structural data, a compelling
The mineralogical and microstructural changes that occur in cementitious systems during hydration are summarized. The discussion concentrates on changes that may occur in iso-thermal systems that do not interact with the environment. The discussion
Benjamin P. Burton, S. McEnroe, C. McCammon, P. Robinson
Single grains of ilmeno-hematite (titanohematite with ferri-ilmenite exsolution lamellae) approximately 250 µm in diameter were taken from Mid-Proterozoic metamorphic rocks in southwest Sweden and the Adirondack Mountains, USA, and were studied at room
Viscoelastic relaxation processes factor into polymer performance and stability throughout an application lifetime. These relaxations are controlled by the polymer network structure and dynamics which occur at different orders of magnitude in time. In most
Stephanie S. Watson, Tarek Marray, Yongyan Pang, Li Piin Sung
Metal oxide fillers, such as titanium dioxide (TiO2) are commonly used in building and construction applications and are added to increase the opacity and/or to improve the mechanics of a coating. However, their photoreactivity can contribute to
Andrew J. Allen, Jeffrey J. Thomas, Hamlin M. Jennings
Microstructure development and the kinetics of hydration of pure tricalcium silicate (C3S) and CaCl2-accelerated C3S pastes were investigated by performing isothermal calorimetry and in situ small-angle neutron scattering (SANS) measurements on parallel
Over the last thirty years, much research has been done on the development of failure event databases and fatigue modeling of crack growth in pressure vessels and piping. According to a USNRC report (NUREG/CR6674, 2000), results of a fatigue crack growth
A.D.W. Todd, P.P. Ferguson, John Barker, M.D. Fleischauer, J.R. Dahn
Small Angle Neutron Scattering (SANS) has been used to compare nanostructured Sn-Co-C alloys produced by vertical axis mechanical attriting to those produced by magnetron sputter deposition. It was found that the attrited materials had grain sizes that
Liangchun (. Yu, Kin P. Cheung, Vinayak Tilak, Greg Dunne, Kevin Matocha, Jason P. Campbell, Kuang Sheng
Mobility is a good indicator of device reliability. High channel mobility is one of the biggest challenges especially in novel devices such as high-k based MOSFET, III-V devices and SiC power MOSFET etc. Accurate measurement of channel mobility is required
The purpose of this study is to develop relevant metrology to measure the appropriate structure-property relationship at a proper length scale to understand the interplay between nanoparticle and polymeric matrix. In this paper, we present the preliminary
Ryan P. Birringer, Roey Shaviv, Thomas Mountsier, Jon Reid, Jian Zhou, Roy H. Geiss, David T. Read, Reinhold Dauskardt
Effects of the chemistry of electroplated copper films on stress-induced voiding and adhesion between the films and a SiN barrier layer are reported. The void density as observed by scanning electron microscopy decreased markedly with increasing Cu purity
Igor Levin, Victor L. Krayzman, Joseph C. Woicik, Terrell A. Vanderah, M. G. Tucker, Thomas Proffen
Reverse Monte Carlo (RMC) refinements of local structure using a simultaneous fit of x-ray/neutron total scattering and EXAFS data were developed to incorporate an explicit treatment of both single- and multiple-scattering contributions to EXAFS. The
Tinh Nguyen, Aline Granier, Kristen L. Steffens, Hajin Lee, Naomi Eidelman, Jonathan W. Martin
We have developed a novel method to covalently functionalize carbon nanotubes (CNTs) that carry free isocyanate (N=C=O) groups. NCO-functionalized CNTs (NCO-fCNTs) are very desirable, because the NCO group is highly reactive with hydrogen-active groups
Amanda L. Forster, Kirk D. Rice, Michael A. Riley, Guillaume Messin, Sylvain H. Petit, Cyril Clerici, Gale A. Holmes, Joannie W. Chin
This publication details the four major phases of analytical development work, coupled with several additional side studies, undertaken by the Office of Law Enforcement Standards in writing the Flexible Armor Conditioning Protocol in NIJ 0101.06. This
Gale A. Holmes, Eun S. Park, Charles M. Guttman, Kathleen M. Flynn, John R. Sieber, Stephanie S. Watson, Kirk D. Rice
Because of the premature failure of soft-body armor that contains the active fiber poly [(benzo-[1,2-d:5,4-d']-benzoxazole-2,6-diyl)-1,4-phenylene] (PBO), the Office of Law Enforcement Standards (OLES) at the National Institute of Standards and Technology
Sang-Won Myoung, James J. Lee, Paul Constantino, Peter Lucas, Brian R. Lawn
Teeth are remarkable biological structures, brittle but resilient. Here we examine the inter-relation between enamel morphology and crack resistance by sectioning human molar teeth after loading to fracture. The sections reveal that many cracks start from
Steven P. Mates, Stephen W. Banovic, Richard L. Rhorer, Timothy J. Burns, Eric P. Whitenton, D Basak
We have developed a unique electrical pulse-heated Kolsky Bar technique for measuring the flow stress of metals at heating rates of up to 6000 °C per second and strain rates up to 10^4 per second. Under these conditions, which are approaching those found
Objective: To review the history, theory and current applications of Weibull analysis sufficient to make informed decisions regarding practical use of the analysis in dental material strength testing. Data: References are made to examples in the engeering
Bruce D. Ravel, Julia C. Lee, Jingen Xiang, Jeffrey Kortright, Kathryn Flanagan
We present a new technique for determining the quantity and composition of dust in astrophysical environments using < 6 keV X-rays. We argue that high resolution X-ray spectra as enabled by the Chandra and XMM-Newton gratings should be considered a
Xiaohong Gu, Dongmei Zhe, Stephanie S. Watson, Guodong Chen, Minhua Zhao, Paul E. Stutzman, Deborah S. Jacobs, Tinh Nguyen, Joannie W. Chin, Jonathan W. Martin
Although inorganic UV absorbers such as zinc oxide (ZnO) and cerium oxide (CeO2) exhibit numerous advantages compared to organic UV absorbers, the mechanisms of how these nanoparticles affect the long-term performance of polymeric coatings are less than
Organofunctionalized montmorillonite clays (MM) have been prepared with ammonium cations having a distribution of alkyl chain lengths. Relative to clays treated with alkylammonium cations having no distribution of chain lengths, the ultimate tensile stress
Jessica M. Torres, Christopher Stafford, Bryan D. Vogt
Understanding the mechanical properties of polymers at the nanoscale is critical in numerous emerging applications. While it has been widely shown that the Tg in thin polymer films decreases due to confinement effects, there is little known about the
Li Piin Sung, Dongmei Zhe, Aaron M. Forster, Peter Krommenhoek, Nancy J. Lin, Sheng Lin-Gibson
Investigation on the effect of nano-silica on the effect of nano-silica on the surface morphology and mechanical properties has been carried out on two-dimensional (2D) gradient polymer-silica composite samples varied in chemical composition (e.g., filler
Elisabeth Mansfield, Roy H. Geiss, Jeffrey A. Fagan
The National Institute of Standards and Technology (NIST) is releasing a series of single-walled carbon nanotube Standard Reference Materials (SRMs) to provide consumers with a well-characterized material for their applications. The SWCNT Reference
Andrew J. Allen, Jan Ilavsky, Fan Zhang, Gabrielle G. Long, Pete R. Jemian
Absolute calibration of small-angle scattering (SAS) intensity data (in units of differential cross-section per unit sample volume per unit solid angle) is essential for many important aspects of quantitative SAS analysis, such as obtaining the number