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Junghyun Lee, Hyun W. Ro, Rui Huang, Thomas Germer, Paul Lemaillet, Christopher Soles, Christopher Stafford
we demonstrated the wrinkling behavior of nanopatterned PS films, whose wrinkle wavelength and resultant morphology depend strongly on geometric parameters of surface patterns as well as the direction of the applied strain relative to the nanopattern
For over 50 years microstructure characterization by small-angle X-ray and neutron scattering (SAXS and SANS) has successfully addressed challenges and surmounted technical barriers impeding the development and application of technological materials. These
Joseph J. Walish, Yin Fan , Andrea Centrone, Edwin L. Thomas
Controlling the color via temperature-induced changes of self-assembled photonic materials is important for their application in sensors and displays. The thermochromic behavior of a PS-P2VP photonic gel was studied (UV-VIS, FTIR) and found to originate
Mauro Zammarano, Szabolcs Matko, Roland H. Kraemer, Rick D. Davis, Jeffrey W. Gilman, Shivani N. Mehta
The objective of this study was to evaluate whether polyurethane foam (PUF) could be produced as a standard reference material for ultimate use in a standard test intended to ensure the smoldering performance of commercially available upholstered furniture
This paper presents the results from a parametric simulation study that was conducted to optimize the design of a high-current 4.5 kV half-bridge Si-IGBT/SiC-JBS hybrid module for medium voltage hard-switched power conversion as well as to compare the
Justin M. Gorham, Robert I. MacCuspie, Kate L. Klein, D H. Fairbrother, Richard D. Holbrook
Due to the increasing use of silver nanoparticles (AgNPs) in consumer products, it is essential to understand how variables, such as light exposure, may change the physical and chemical characteristics of AgNP suspensions. To this end, the effect of 300 nm
Andrew J. Slifka, Elizabeth S. Drexler, Neha N. Rustagi, Damian S. Lauria, Joseph D. McColskey, Robert L. Amaro
Fatigue crack growth tests were conducted on two API 5L X52 pipeline steel alloys. One alloy was from a new linepipe that was installed for hydrogen service in 2011. The other alloy was from a vintage pipe that first saw natural gas service in 1964
An in-depth analysis of U.S. residential fire statistics shows that although the total number of fires and deaths due to mattress fires has dropped as a result of several regulatory approaches, the mattress/bedding fires continue to account for one of the
Atomically uniform nucleation products of ligated metal nanoclusters are observed irrespective of reduction conditions for metal-bidentate ligand systems. Monodentate ligands are not reported to wield similar control, indicating steric contributions of
Christopher C. White, Donald L. Hunston, Kar T. Tan
Previous industry consensus postulated that four elements of the weather: Temperature, Humidity, Ultraviolet Radiation, and Mechanical loading were responsible for the majority of the changes observed in sealants exposed to outdoor weathering. The NIST
Ann C. Chiaramonti Debay, Sten Vollebregt, R. Ishihara, Hugo Schellevis, Kees Beenakker
In this work the electrical contact resistance and length dependant resistance of vertically aligned carbon nano- tubes (CNT) grown at 500 °C with high tube density (1011) are investigated by measuring samples with different CNT lengths. From scanning
Matthew T. Hunley, Fahriye N. Sari, Kathryn L. Beers
As the research interest in degradable polymers has risen, an ever increasing number of manuscripts report the synthesis of copolymers through ring-opening copolymerization techniques. However, the mechanism of copolymerization remains unexplored. In
Christopher N. McCowan, Elizabeth S. Drexler, Jeffrey W. Sowards
Fracture surfaces of X100 pipeline steels were examined with optical and electron microscopy following fracture testing. The fractures show chevron-like fracture patterns, but are distinctly different from classic chevron fracture. The chevron-like
In this study, environmentally stressed OS fabrics containing melamine fiber blends were evaluated for thermal and mechanical properties that are critical to the protective performance of firefighter turnout gear. Environmental stress factors that affect
Small-angle neutron scattering (SANS) studies are performed to investigate the stability and geometry of hydrogen-bonded pyrene-filled c-hexylprogallol[4]arene (PgC 6-pyrene) nanotubular frameworks. In the solid state, hydrogen-bonded pyrogallol[4]arene
Tinh Nguyen, Bastien T. Pellegrin, Coralie Bernard, Savelas A. Rabb, Paul E. Stutzman, Justin M. Gorham, Xiaohong Gu, Lee L. Yu, Joannie W. Chin
Nanofillers are increasingly used for enhancing multiple properties of polymeric materials in many applications. However, polymers are susceptible to photodegradation by solar ultraviolet (UV) radiation Therefore, nanofillers in a polymer nanocomposite
Thermogravimetric analysis with an SC-cut quartz crystal microbalance (QCM) were demonstrated at temperatures in the range from 20 C to 450 C. A measurement system was built around a crystal sensor head that was mounted in a small tube furnace. Changes in
A series of three Hydrogen in Titanium Alloy Standard Reference Materials (SRMs 2452, 2453, and 2454) were prepared with hydrogen mass fractions bracketing the hydrogen specification limit of 125 mg/kg. Commercial titanium alloy Ti6Al4V (6 % aluminum, 4 %
Shonali Nazare, Jeffrey W. Gilman, Mauro Zammarano, Luke Haverhals, W.Matthew Reichert, Hugh De Long, Paul C. Trulove
In addition to being efficient solvents for biopolymers, several ionic liquids (ILs) have been shown to be effective solvents for synthetic polymers such as meta-aramids, i.e., Nomex ® (1-5). In this report, meta-aramid/cotton composites are generated by
Rusen Yan, Qin Zhang, Wei Li, Irene G. Calizo, Tian T. Shen, Curt A. Richter, Angela R. Hight Walker, Xuelei X. Liang, David J. Gundlach, Nhan Van Nguyen, Huili G. Xing, Alan Seabaugh
We determined the band alignment of a graphene-oxide-silicon structure using internal photoemission spectroscopy. From the flatband voltage and Dirac voltage we infer a 4.3 10e11 cm-2 negative extrinsic charge present on the graphene surface. Also, we
First-principles density functional theory calculations are used to investigate alpha-MnO2, a structure containing a framework of corner and edge sharing MnO6 octahedra with tunnels in between. Calculations show that placing additional species, such as K+
Xiaohong Gu, Minhua Zhao, Stephanie S. Watson, Tinh Nguyen, Joannie W. Chin, Jonathan W. Martin, Dongmei Zhe, Guodong Chen
Polymers are widely used as exterior coatings in buildings, bridges, aircrafts, and automobiles for both protection and aesthetic purposes. However, the sustainability and service life of the applied coatings is limited due to the photodegradation of
Mauro Zammarano, Edward D. McCarthy, Douglas M. Fox, Paul H. Maupin, Li Piin Sung, Yeon S. Kim
One of the most enduring problems in the evolution of science and technology using nanoscale materials is the characterization of their morphology in macroscopic systems.1 This involves spatial and orientation distribution, which may be multimodal and
Peter M. Johnson, Edwin Chan, Jun Y. Chung, Junghyun Lee, Christopher Stafford
Reverse osmosis (RO) and nanofiltration (NF) membranes are comprised of a dense active layer supported by a porous support. Commercial active layer are highly crosslinked polyamides that are formed through interfacial polymerization directly on the support