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Search Publications

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Displaying 5601 - 5625 of 74364

Atomic force microscopy for nanoscale mechanical property characterization

November 10, 2020
Author(s)
Gheorghe Stan, Sean King
Over the past several decades, atomic force microscopy (AFM) has advanced from a technique used primarily for surface topography imaging to one capable of characterizing a range of chemical, mechanical, electrical, and magnetic material properties with sub

Parallel multi-parameter study of PEI-functionalized gold nanoparticle synthesis for bio- medical applications: Part 2. Elucidating the role of surface chemistry and polymer structure on performance

November 10, 2020
Author(s)
Tae Joon Cho, Justin M. Gorham, John M. Pettibone, Jingyu Liu, Jiaojie Tan, Vincent A. Hackley
Despite the breadth and quality of published work in this area, it remains unclear how the specific properties of polyethyleneimine (PEI) and the methods utilized to conjugate it to gold nanoparticles (AuNPs) impact the final product morphology and

Phase-coherent sensing of the center-of-mass motion of trapped-ion crystals

November 9, 2020
Author(s)
Matthew Affolter, Kevin Gilmore, Elena Jordan, John Bollinger
Measurements of the center-of-mass motion of a trapped-ion crystal that are phase- coherent with an external force are reported. These experiments are conducted far from the trap motional frequency on a two-dimensional trapped ion crystal of approximately

Parallel Generalized Real Symmetric-Definite Eigenvalue Problem

November 6, 2020
Author(s)
James S. Sims, Maria B. Ruiz
A computationally fast Fortran 90+ quadruple precision portable parallel GRS- DEP (generalized real symmetric-definite eigenvalue problem) package suitable for large (80,000 x 80,000 or greater) dense matrices is discussed in this paper.

Shoulder fillet effects in strength distributions of MEMS components

November 6, 2020
Author(s)
Frank W. DelRio, Brad L. Boyce, Jake T. Benzing, Lawrence H. Friedman, Robert F. Cook
The failure forces and fracture strengths of polysilicon MEMS components in the form of stepped tensile bars with shoulder fillets were measured using a sequential failure chain methodology. Approximately 150 specimens for each of four fillet geometries

Broadening of the drumhead mode spectrum due to in-plane thermal fluctuations of two-dimensional trapped-ion crystals in a Penning trap

November 5, 2020
Author(s)
Athreya Shankar, Chen Tang, Matthew Affolter, Kevin Gilmore, Daniel H. Dubin, Scott E. Parker, Murray Holland, John Bollinger
Two-dimensional crystals of ions stored in Penning traps are a leading platform for quantum simulation and sensing experiments. For small amplitudes, the out-of-plane motion of such crystals, which is exploited for quantum information protocols, can be

Existence conditions for phononic frequency combs

November 5, 2020
Author(s)
Zhen Qi, Curtis R. Menyuk, Jason Gorman, Adarsh V. Ganesan
Recently, the mechanical analog of optical frequency combs, phononic frequency combs, have been demonstrated in mechanical resonators and have gained interest since their comb frequencies can be in the range of kilohertz to gigahertz. The physical origin

Large Outdoor Fires and the Built Environment (LOF&BE): Summary of Virtual Workshop

November 4, 2020
Author(s)
Samuel L. Manzello, Sayaka Suzuki, Sara McAllister, Brian Lattimer, Daniel Gorham, Alexander Filkov, Maria Theodori, Xinyan Huang
Two virtual workshops of the permanent working group, sponsored by the International Association for Fire Safety Science (IAFSS), entitled Large Outdoor Fires and the Built Environment (LOF&BE), were held this past August (2020). The first session was held

Modeling Hierarchical Systems with Operads

November 4, 2020
Author(s)
Spencer Breiner, Olivier Marie Rose, Blake S. Pollard, Eswaran Subrahmanian
This paper applies operads and functorial semantics to address the problem of failure diagnosis in complex systems. We start with a concrete example, developing a hierarchical interaction model for the Length Scale Interferometer, a high-precision

Noise Influence on Scattering-Parameter Measurements

November 4, 2020
Author(s)
Dazhen Gu, Jeffrey A. Jargon, Matthew J. Ryan, Anouk Hubrechsen
We present a general model of noise-influenced scattering (S) parameter measurements performed by a vector network analyzer (VNA). The residual error of the S-parameter due to the noise appears like a complex Gaussian quotient. The statistical analysis of

ENABLING TRACEABILITY IN AGRI-FOOD SUPPLY CHAINS USING AN ONTOLOGICAL APPROACH

November 3, 2020
Author(s)
Evan K. Wallace, Farhad Ameri, Reid Yoder
Traceability of food products to their sources is critical for quick responses to a food emergency. US law now requires stakeholders in the agri-food supply chain to support traceabil-ity by tracking food materials they acquire and sell. However, having

Error Quantification in Dynamic Applications of Weakly Nonlinear Transducers

November 3, 2020
Author(s)
Lautaro D. Cilenti, Akobuije Chijioke, Balakumar Balachandran
Characterization and quantification of dynamic measurements is an ongoing area of research in the metrological community as new calibration methods are being developed to address dynamic measurement applications. The development undertaken to date largely

Multiphase Magnetism in Yb 2 Ti 2 O 7

November 3, 2020
Author(s)
Allen Scheie, Jonas Kindervater, Shu Zhang, Hitesh Changlani, G. Sala, Georg Ehlers, Andre Heinemann, Gregory Tucker, Seyed Koohpayeh, Collin L. Broholm

Cryogenic Calibration of a Quantum-based Radio Frequency Source

November 2, 2020
Author(s)
Alirio De Jesus Soares Boaventura, Justus A. Brevik, Dylan Williams, Anna E. Fox, Manuel C. Castellanos Beltran, Peter F. Hopkins, Paul D. Dresselhaus, Samuel P. Benz
We report on the calibration of quantum-based radio frequency waveforms generated by a Josephson arbitrary waveform synthesizer system. We measure these waveforms using a vector network analyzer and calibrate them at 4 K using a custom-designed cryogenic

Cryogenic Calibration of a Quantum-based Radio Frequency Source

November 2, 2020
Author(s)
Alirio De Jesus Soares Boaventura, Justus Brevik, Dylan Williams, Anna Fox, Manuel Castellanos Beltran, Pete Hopkins, Paul Dresselhaus, Samuel P. Benz
We report on the calibration of quantum-based radio frequency waveforms generated by a Josephson arbitrary waveform synthesizer system. We measure these waveforms using a vector network analyzer and calibrate them at 4 K using a custom-designed cryogenic

Efficient photoinduced second-harmonic generation in silicon nitride photonics

November 2, 2020
Author(s)
Xiyuan Lu, Gregory Moille, Ashutosh Rao, Daron Westly, Kartik Srinivasan
Silicon photonics lacks a second-order nonlinear optical (chi(2)) response in general because the typical constituent materials are centro-symmetric and lack inversion symmetry, which prohibits chi(2) nonlinear processes such as second harmonic generation

Endothermic reaction at room temperature enabled by deep-ultraviolet plasmons

November 2, 2020
Author(s)
Canhui Wang, Wei-Chang Yang, David Raciti, Alina Bruma, Ronald Marx, Amit Agrawal, Renu Sharma
Sequestration and conversion of CO2 is a promising method for remedying climate change. However, current technologies remain limited due to infeasible system demands and outputs, such as high-temperature/pressure conditions, use of precious metals, or low

Zero-valent iron sand filtration can reduce human and plant pathogenic bacteria while increasing plant growth promoting bacteria in reclaimed water

November 2, 2020
Author(s)
Prachi Kulkarni, Nathanael David Olson, Joseph N. Paulson, Emmanuel F. Mongodin, Mihai Pop, Amy R. Sapkota
The increasing use of reclaimed water for irrigation in areas that lack access to advanced wastewater treatment and reclaimed water distribution systems calls for an examination of irrigation-site-based treatment technologies that can improve the quality
Displaying 5601 - 5625 of 74364