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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
Mariano A. Real, Tian T. Shen, George R. Jones Jr., Randolph Elmquist, Johannes A. Soons, Albert Davydov
Epitaxial growth of graphene layers on 6H-SiC(0001) substrates have been studied in order to improve graphene's performance for metrological applications. A face-to-face (FTF) sublimation method at 2000 °C and in Ar background atmosphere is used to inhibit
Najib Cheggour, Arend Nijhuis, H J. Krooshoop, Xifeng Lu, Jolene D. Splett, Theodore C. Stauffer, Loren F. Goodrich, Matthew C. Jewell, Arnaud Devred, Y Nabara
A benchmarking experiment was conducted to compare strain measurement facilities at the National Institute of Standards and Technology (NIST) and the University of Twente. The critical current of a bronze-route Nb 3Sn wire, which was fabricated for the
A method of measuring biaxial stress-strain curved for sheet metal samples subjected to large plastic strains is described for one example aluminum alloy (AA 5754-O). The method uses a prtable X-ray diffraction (XRD) system to measure in situ stresses
David E. Morris, Melissa L. Mather, Carl Simon Jr., John A. Crowe
The performance of polymer based scaffolds used in regenerative medicine is linked to their structural properties and as such strategies for structural characterization of scaffolds have been developed. X-ray microscopic computed tomography (X-ray micro CT
Huagen H. Peng, Madhu Sudan Tyagi, Kirt A. Page, Christopher Soles
The relationship between ion transport and polymer dynamics is central to the pursuit of solid polymer electrolytes for lithium batteries. This understanding is critical to achieve solid polymer electrolyte systems of sufficiently high ion conductivities
Christopher C. White, Donald L. Hunston, Kar T. Tan, James J. Filliben
An accurate service life prediction model is urgently needed for building joint sealants to reduce the enormous cost associated with long-term field weathering. A stepping stone to the success of this effort is the precise control of environmental
Carl G. Simon Jr., Kaushik Chatterjee, Alison M. Kraigsley, Joachim Kohn, Durgadas Bolikal
Current methods for screening cell-material interactions typically utilize two-dimensional (2D) culture format where cells are cultured on flat surfaces. However, there is a need for combinatorial and high-throughput screening methods to systematically
Carl G. Simon Jr., Girish Kumar, Kaushik Chatterjee, Stevephen Hung
Protein adsorption is known to direct biological response to biomaterials and is important in determining cellular response in tissue scaffolds. In this study we investigated the effect of adsorbed serum proteins on cell attachment and proliferation in
Fan Zhang, Andrew J. Allen, Lyle E. Levine, Jan Ilavsky, Gabrielle G. Long
Ultra-small-angle X-ray scattering—X-ray photon correlation spectroscopy (USAXS-XPCS) is a novel measurement technique for the study of equilibrium and slow nonequilibrium dynamics in disordered materials. This technique fills an existing gap between the
Fire barrier fabrics are expected to play an increasingly important role in complying with existing and proposed soft furnishing flammability regulations. The number of commercial fire blocking technologies is large in order to accommodate the vast
The need for bone defect repair and regeneration arises from trauma, disease, congenital deformity, and tumor resection. Bone fracture occurs to seven million people each year in the United States, and musculoskeletal conditions cost $215 billion annually