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Christoph Rohmann, Maicol A. Ochoa, Michael P. Zwolak
The adsorption of metal atoms on nanostructures, such as graphene and nanotubes, plays an important role in catalysis, electronic doping, and tuning material properties. Quantum chemical calculations permit the investigation of this process to discover
Ryan P Murphy, Harold Wickes Hatch, Nathan NMN Mahynski, Vincent K. Shen, Norman J. Wagner
Dynamic arrest transitions of model, thermoreversible dispersions of adhesive hard rods are measured as a function of absolute temperature Τ = 15 -40 °C, aspect ration L/D{approximately equal}3-7, and volume fraction φ0.1-0.5. The critical gel temperature
Jack F. Douglas, Jinpeng Fan, Hamed Emamy, Francis W. Starr, Alexandros Chremos
While glass formation of linear chain polymers has been widely explored, comparatively little is known about glass formation in star polymer melts. We study the segmental dynamics of star polymers via molecular dynamics simulations and contrast the
Hypothesis. Rheology combined with Small Angle Neutron Scattering (Rheo-SANS) can determine the local structural order in Worm-like Micelle (WLM) solutions, when the shear rate increases beyond the ending of the gradient shear banding, where the micellar
Di Yi, Yujia Wang, Olaf M. J. van t'Erve, Liubin Xu, Hongtao Yuan, Michael J. Veit, Purnima P. Balakrishnan, Yongseong Choi, Alpha T. N'Diaye, Padraic Shafer, E. Arenholz, Alexander Grutter, Haixuan Xu, Pu Yu, Berend T. Jonker, Yuri Suzuki
Electric fields have been shown to transform materials with respect to their structure and properties, thus enabling many applications ranging from batteries to spintronics. Recently electrolytic gating, which can generate large electric fields and voltage
Nima Shahkaramipour, Amin Jafari, Thien Tran, Christopher Stafford, Chong Cheng, Haiqing Lin
Superhydrophilic zwitterions have been extensively exploited for surface modification to improve antifouling properties. However, it remains challenging to form layers of 20 nm with high zwitterion content on the surfaces with different degrees of
Leora E. Dresselhaus-Cooper, Dmitro Martynowych, Fan Zhang, Charlene Tsay, Jan Ilavsky, SuYin Wang, Yu-Sheng Chen, Lara Leininger, Keith A. Nelson
We demonstrate a strongly thresholded response in cyclotrimethylene trinitramine (RDX) that is cylindrically shocked using a novel waveguide geometry. Using ultrafast single-shot multi-frame imaging, we demonstrate that a 100-μm diameter single crystal of
Separation of ethane from ethylene is a very important but challenging process in the petrochemical industry. Finding an alternative method would reduce the energy needed to make the 170 million tons of ethylene manufactured worldwide each year. Adsorptive
Jack F. Douglas, Andrea Giuntoli, Alexandros Chremos
We investigate how varying molecular topology of polymers influences crystallization in thin polymer films. In particular, we simulate linear and star polymers having a progressively increasing number of arms (f ≤ 16) for fixed molecular mass of polymer
David R. Black, Marcus H. Mendenhall, Albert Henins, James J. Filliben, James P. Cline
The National Institute of Standards and Technology (NIST) certifies a suite of Standard Reference Materials (SRMs) to evaluate specific aspects of instrument performance of both x-ray and neutron powder diffractometers. This report describes SRM 660c, the
Varun Verma, Jascha A. Lau, Arnab Choudhury, Li Chen, Dirk Schwarzer, Alec M. Wodtke
Molecules are quantum objects; therefore, isomerization fundamentally involves quantum states bound within a molecular potential energy function with multiple minima. For isolated gas-phase molecules, eigenstates well above the isomerization saddle points
Adrian P. Defante, Steven D. Hudson, Cavan K. Kalonia, Emma Keegan, Steven Bishop, Paul Santacroce, Satish Hasige
Subvisible particle formation which occurs after the sterile filtration step of the fill/finish process is challenge that may occur during the development of biotherapeutics with complex molecular structures. Here, we show that a stainless-steel pump head
The separation of ethane (C 2H 6) from ethylene (C 2H 4) is of prime importance in the production of polymergrade C 2H 4 for industrial manufacturing. It is very challenging and still remains unexploited to fully realize efficient C 2H 6/C 2H 4 separation
Microstructural and morphological evolution during bottom-up Cu filling of TSV in a CuSO4-H2SO4-Cl- poloxamine electrolyte is examined. Deposition proceeds in two distinct stages beginning with a passive-to-active state transition on the via sidewalls
Jackson J. Bauer, Ethan R. Rosenberg, Subhajit Kundu, K. Andre Mkhoyan, Patrick Quarterman, Alexander Grutter, Brian Kirby, Julie Borchers, Caroline A. Ross
Magnetic insulators, such as the rare-earth iron garnets, are promising materials for energy-efficient spintronic memory and logic devices, and their anisotropy, magnetization and other properties can be tuned over a wide range through selection of the
Hayden Carlton, Kathryn L. Krycka, Markus Bleuel, David Huitink
The study and fundamental understanding of magnetic nanoparticle induction heating remain critical for the advancement of magnetic hyperthermia technologies. Complete characterization of not only the nanoparticles themselves but their inter-particle
Melody A. Morris, Seung Hyun Sung, Priyanka M. Ketkar, Joseph Dura, Ryan Nieuwendaal, III Epps
The optimization of ionic conductivity and lithium-ion battery stability can be achieved by independently tuning the ion transport and mechanical robustness of block polymer (BP) electrolytes. However, the ionic conductivity of BP electrolytes is
Tungsten, a non-Li-intercalating material, was used as a platform to study solid-electrolyte interface/interphase (SEI) formation in lithium hexafluorphosphate in mixed diethyl carbonate (DEC)/ethylene carbonate (EC) electrolyte solutions using in situ
We report here on the design, fabrication and calibration of nanocalorimeter sensors used in the NIST Nanocalorimetry Measurements Project. These small scale thermal analysis instruments are produced using silicon microfabrication approaches. A single
Xiaoyi Chen, Zhihao Feng, Janavi Gohil, Christopher Stafford, Ning Dai, Liang Huang, Haiqing Lin
Reduced-graphene oxide (r-GO) membranes with narrow channels exhibit salt rejections comparable to conventional nanofiltration (NF) membranes. However, their water permeances are much lower because of the high tortuosity for water permeation. Herein we
Xiaoran Liu, Sobhit Singh, Brian Kirby, Zhicheng Zhong, Yanwei Cao, Banabir Pal, Mikhail Kareev, Srimanta Middey, John W. Freeland, Padraic Shafer, Elke Arenholz, David Vanderbilt, Jak Chakhalian
We report on the emergent magnetic state of (111)-oriented CoCr 2O 4 ultrathin films sandwiched by Al 2O 3 in the quantum confined geometry. At the two-dimensional crossover, polarized neutron reflectometry reveals an anomalous enhancement of the total
Jack F. Douglas, Mengxue Zhang, Clinton Wiener, Pablo Sepulveda-Medina, Bryan D. Vogt Vogt
Hydrophobically modified copolymers provide a versatile platform of hydrogel materials for diverse applications, but the influence of salts on the swelling and material properties of this class of hydrogels has not been extensively studied. Here, we