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Edward Garboczi, Yibing Zuo, Zhiwei Qian, Guang Ye
Many particle-based numerical models have been used to simulate the hydration process of cementitious materials. But most of these models employ regular shape particles, such as spheres, to represent cement, slag or fly ash, which neglect the influence of
Alexander D. Haywood, Kathleen Weigandt, Partha Saha, Matthew Noor, Micha J. Green, Virginia A. Davis
Understanding microstructure and shear response is a prerequisite for the controlled and predictable assembly of anisotropic nanomaterials into large area structures. Much of the framework for understanding the rheological behavior of lyotropic dispersions
Erkan NMN Senses, Suresh Narayanan, Yimin NMN Mao, Antonio Faraone
Using x-ray photon correlation spectroscopy, we examined slow nanoscale motion of silica nanoparticles individually dispersed in entangled poly (ethylene oxide) melt at particle volume fractions up to 42%. The nanoparticles, therefore, serve as both
Stephanie S. Watson, Chiara C. Ferraris, Jason D. Averill
The resilience of U.S. communities, defined as the "ability to withstand and recover rapidly from disruptive events," is directly dependent upon the ability of the built environment to maintain and support the functions upon which modern society has come
Danyal J. Turkoglu, Huaiyu H. Chen-Mayer, Rick L. Paul, Rolf L. Zeisler
The accuracy of low-level hydrogen measurements with prompt gamma-ray activation analysis (PGAA) depends on identifying and accounting for all background H signal, including interfering signals. At the cold-neutron (CN)PGAA facility at the NIST Center for
Carl G. Simon Jr., Nathan A. Hotaling, Kapil Bharti, Vladimir Khristov, Arvydas Maminishkis
A scaffold handling device (SHD) has been designed that can switch from gentle suction to positive pressure to lift and place nanofiber scaffolds. In tissue engineering laboratories, delicate fibrous scaffolds, such as electrospun nanofiber scaffolds, are
Samples of Gorilla® glass (Corning®) from several touchscreen mobile phones were prepared and analyzed using phototransferred thermoluminescence (PTTL) in an attempt to retrospectively assess radiation doses absorbed by the glass for potential applications
Jeffrey J Richards, Julie Beth Hipp, John K Riley, Norman J. Wagner, Paul Butler
High-structured carbon fillers are ubiquitous as the conductive additive comprising suspension-based electrochemical storage technologies. Carbon black networks provide the necessary electric conductivity as well as mechanical percolation in the form of a
Jack F. Douglas, Hao Zhang, Xuhang Tong, Xinyi Wang
We investigate the collective molecular motions and diffusion of water molecules in the mobile interfacial region of the secondary prismatic plane of hexagonal ice by molecular dynamics simulation based on the TIP4P/2005 water potential and metrologies of
In August 2014, Dr. Anton Heidemann published a short, personal history of the development of neutron backscattering. His fascinating article 1 described the technical innovations that were made during the development of this technique, and it is
Kevin J. Dwyer, Hyun S. Kim, David S. Simons, Joshua M. Pomeroy
In this study, we examine the mechanisms leading to 29Si incorporation into highly enriched 28Si films deposited by hyperthermal ion beams at elevated temperatures in the dilute presence of natural abundance silane (SiH4) gas. Enriched 28Si is a critical
In this study, two halogen-free inorganic flame retardants, ammonium polyphosphate (APP) and aluminum hydroxide (ATH) were added to wood-flour/polypropylene composites (WPCs) at different APP to ATH mass ratios and at a constant total flame retardant
Fan Yang, Gang Xu, Yibo Dou, Bin Wang, Heng Zhang, Hui Wu, Wei Zhou, Jian-Rong Li, Banglin Chen
The design of stable electrolyte materials of high proton conductivity for fuel cell is still a great challenge to date. Herein we report a chemically stable and structurally flexible MOF, BUT-8(Cr) a, with high-density of -SO 3H sites on its pore surfaces
Mary Anne Manumpil, Carmen Leal-Cervantes, Matthew R. Hudson, Craig Brown, Hemamala I. Karunadasa
Exposure to humid oxygen or ambient air affords a 5-or-der-of-magnitude increase in the electronic conductivity of a new Prussian blue analog incorporation Co(II) and V(IV)-oxo units. Oxidation produces a mixed-valence framework, where the oxygen exposure
Shahriyar Keshavarz, Zara Molaeinia, Andrew C. Reid, Stephen A. Langer
This paper develops a framework to obtain flow stress of Nickel-based superalloys as a function of gamma-gamma prime morphology. In general, the two-phase gamma-gamma prime morphology in Nickel-based superalloys can be divided into three variables
Fe2SnSe4 was synthesized by elemental reaction and densified using hot pressing in order to investigate the transport properties. It crystallizes in the orthorhombic space group Pnma with the olivine-type crystal structure. Our report describes results and
Wei Guo, Cassandra M. Reese, Li Xiong, Phillip K. Logan, Brittany J. Thompson, Christopher Stafford, Anton Ievlev, Bradley S. Lokitz, Olga S. Ovchinnikova, Derek L. Patton
We report a simple route to engineer ultrathin polymer brush surfaces with wrinkled and creased morphologies using postpolymerization modification (PPM), where the length scale of the buckled features can be tuned using PPM reaction time and sequence. We
Pu-Jui Su, Bernard Haochih Liu, Stephanie S. Watson, Li Piin Sung
Nanoindentation was used to monitor the changes in surface mechanical property of nano-titanium dioxide (nanoTiO2)/acrylic urethane (AU) composites exposed to high intensity UV radiation at 55 ℃ and dry conditions. Five TiO2 nanoparticles of similar size
Zirconias, the most durable of the dental ceramics, are increasingly being fabricated in monolithic form for a range of clinical applications, circumventing issues associated with weak porcelain veneers. Yttria-based tetragonal zirconia polycrystal (Y-TZP)
Kyoung E. Kweon, Joel B. Varley, Patrick Shea, Nicole Adelstein, Prateek Mehta, Tae Wook Heo, Terrence J. Udovic, Vitalie Stavila, Brandon C. Wood
Li 2B 12H 12 and Na 2B^12^H 12 closoboranes exhibit unusually high ionic conductivity, making them attractive as a new class of candidate electrolytes in solid-state Li- and Na-ion batteries. However, further optimization of these materials requires a