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Polymer-nanoparticle (NP) interfacial interactions are expected to strongly influence the properties of nanocomposites, but surprisingly, experiments often report small or no changes in the glass transition temperature, Tg. To understand this paradoxical
Those readers who have a library with the first bound copies of ARI may find it enjoyable to compare Volume 1, No.1 from 1956 with an issue from Volume 118 in 2016. The range of applications has shifted away from agricultural and industrial uses of
Numerous experiments reveal that the dynamics of glass-forming polymer melts is profoundly influenced by the application of pressure, but a fundamental microscopic understanding of these observations remains incomplete. Here, we explore structural
Neal C. Pisenti, Alessandro Restelli, Ben J. Reschovsky, Daniel Barker, Gretchen K. Campbell
We present an ultra-low noise, high-voltage driver suited for use with piezoelectric actuators and other low- current applications. The architecture uses a flyback switching regulator to generate up to 250V in our current design, with an output of 1 kV or
Two Way Satellite Time and Frequency Transfer (TWSTFT or TW) is a commonly used technique to compare time and frequency precisely among the time and frequency laboratories. The precision of TWSTFT on time comparison is about 0.5 ns or even better, which
Joshua M. Pomeroy, Kevin J. Dwyer, Ke Tang, Hyun S. Kim, Aruna N. Ramanayaka, David S. Simons
High quality, enriched silicon contains an exceptionally low density of defects and unpaired electron and nuclear spins that allow candidate qubits (single donors or quantum dots) to exhibit very long dephasing times compared to silicon with a natural
Saya Takeuchi, William R. McGehee, Jennifer L. Schaefer, Truman M. Wilson, Kevin A. Twedt, Christopher L. Soles, Vladimir P. Oleshko, Eddie H. Chang, Jabez J. McClelland
The development of Li focused ion beams (Li-FIB) enables controlled Li ion insertion into materials with nanoscale resolution. We take the first step toward establishing the relevance of the Li-FIB for studies of ion dynamics in electrochemically active
I will discuss the considerations that were important in the design of the current version of Coordinated Universal Time. The design includes the addition of additional leap seconds to keep Coordinated Universal time within 0.9 s of the UT1 time scale
Global Positioning System (GPS) disciplined oscillators and clocks serve as standards of frequency and time in numerous calibration and metrology laboratories. They also serve as trusted frequency and time references in many industries, perhaps most
We have measured the charging of a dielectric microparticle after interacting with a glass substrate using optical tweezers to control the particle, measure its charge with sensitivity of a few electrons and precisely position the particle on the substrate
The spectrum of platinum was observed in the (300 to 2100) A wavelength region. The (5d5 + 5d46s) - 5d46p transition array of five times ionized platinum, Pt VI, has been investigated and 1390 spectral lines have been classified in the region of (399 to
The wide range of chemical compositions exhibited by polymer materials leads to materials having highly tunable cohesive energy strength epsilon, and many of the properties that make polymers so useful as structural and responsive materials in
We systematically investigate the thermodynamic and dynamic properties of a model glass-forming (GF) polymer melt by molecular dynamics simulation over a wide range of pressures (P) and temperatures (T). We first analyze the density, thermal expansion
Shaun C. Burd, David T. Allcock, Tomi Leinonen, Jussi-Pekka Penttinen, Daniel H. Slichter, Raghavendra Srinivas, Andrew C. Wilson, Robert Jordens, Micrea Guina, Dietrich G. Leibfried, David J. Wineland
Experiments in atomic, molecular, and optical (AMO) physics rely on lasers at many different wave- lengths and with varying requirements on spectral linewidth, power and intensity stability. Vertical external-cavity surface-emitting lasers (VECSELs), when
Gary S. Grest, Jack F. Douglas, Mike S. Kent, M Whitmore
We provide a unified description of polymer brushes anchored to flat, repulsive surfaces in good solvents, for systems ranging from the one limit of an isolated chain through to the opposite limit of very high anchoring densities, based on molecular
Quentin Smets, Anne S. Verhulst, Salim El Kazzi, David J. Gundlach, Curt A. Richter, Anda Mocuta, Nadine Collaert, Aaron Thean, Marc Heyns
The effective bandgap for heterojunction band-to-band tunneling (Eg,eff) is a crucial design parameter for heterojunction TFET. However, there is significant uncertainty on Eg,eff, especially for In0.53Ga0.47As/GaAs0.5Sb0.5. This makes TFET performance
Michael Ondrusek, Veronica P. Lance, Eric Stengel, Menghua Wang, Zhongping Lee, Jianwei Wei, Junfang Lin, Chuanmin Hu, Charles Kovach, David English, Jennifer Cannizzaro, Alex Gilerson, Sam Ahmed, Carlos Carrizo, Ahmed El-Habashi, Robert Foster, Matteo Ottaviani, Robert Arnone, Sherwin Ladner, Wesley Goode, Ryan Vandermeulen, Nicholas Tufillaro, Jasmine Nahorniak, Curtiss Davis, Joaquim I. Goes, Kali McKee, Scott Freeman, Joaquin E. Chaves Cedeno, Kenneth Voss, B. Carol Johnson
The spectrum of platinum was observed in the (300-2100) Å wavelength region. Grazing and normal incidence VUV spectrographs have been used to record the spectrum. The (5d3 + 5d26s) - 5d26p transition array of seven times ionized platinum, Pt VIII, has been
Makfir Sefa, Zeeshan Ahmed, James A. Fedchak, Nikolai Klimov, Julia Scherschligt
We describe a vacuum apparatus for determining the outgassing rate into vacuum, the diffusion coefficient, and the amount of gas absorbed for various materials. The diffusion coefficient is determined from a model applied to time-dependent desorption data
Behrang H. Hamadani, Juan P. Babaro, Kevin G. West
Spectral response measurements of germanium-based triple-junction solar cells were performed under a variety of light and voltage bias conditions. Two of the three junctions exhibited voltage and light bias dependent artifacts in their measured responses
Bettye C. Johnson, Catherine C. Cooksey, Ahmed El-Habashi, David English, Georgi T. Georgiev, Sherwin Ladner, Veronica P. Lance, Michael Ondrusek, Ryan Vandermeulen
Annual dedicated ocean color validation cruises off the East Coast of the USA were started in November 2014 with support from the NOAA office of Marine and Air Operations with primary focus on VIIRS/SNPP and upcoming JPSS missions. A portion of the
The spectrum of platinum was observed in the (300-2100) Å wavelength region. The (5d4 + 5d36s) - 5d36p transition array of six times ionized platinum, Pt VII, has been investigated and 759 spectral lines have been classified in the region of (337-1273) Å
We investigate the thermodynamic and dynamic properties of a model unentangled glass-forming polymer melt over a wide range of pressures (P) and temperatures (T) using molecular dynamics simulation. We show that the T dependence of the reduced thermal
Monomer molecular and chemical structures represent the most important characteristics of polymers that directly determine the basic molecular parameters (such as cohesive energy) influencing the physical properties of polymer materials. However, a