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Ramya Vishnubhotla, Sarah Robinson, Jon R. Askim, Christopher B. Montgomery, Kristen L. Steffens, Herman O. Sintim, Stephen Semancik
Conformational changes of single-stranded DNA (ssDNA) play an important role in a DNA strand's ability to bind to target ligands. A variety of factors can influence conformation, including temperature, ionic strength, pH, buffer cation valency, strand
Joseph Fowler, Galen O'Neil, Bradley K. Alpert, Douglas Bennett, Edward V. Denison, William Doriese, Gene Hilton, Lawrence T. Hudson, Young I. Joe, Kelsey Morgan, Daniel Schmidt, Daniel Swetz, Csilla I. Szabo-Foster, Joel Ullom
We use an array of transition-edge sensors, cryogenic microcalorimeters with 4 eV energy resolution, to measure the x-ray emission-line profiles of four elements of the lanthanide series: praseodymium, neodymium, terbium, and holmium. The spectrometer also
Papa K. Amoah, Pengtao Lin, Helmut Baumgart, Yaw S. Obeng, Rhonda R. Franklin
Metal-oxide semiconductor gas sensors based on chemical resistivity necessarily involve making electrical contacts to the sensing materials. These contacts are imperfect and introduce errors into the measurements. In this paper, we demonstrate the
Varun Verma, Jeff Chiles, Adriana Lita, Richard Mirin, Sae Woo Nam, Yao Zhai, Adam McCaughan, Emma Wollman, Alexander Walter, Boris Korzh, Jason Allmaras, Ekkehart Schmidt, S. Frasca, Matthew Shaw
Superconducting nanowire single-photon detectors, or SNSPDs, have become the highest-performing class of single-photon detectors in the near-IR. At telecom wavelengths, SNSPDs have demonstrated detection effi- ciency above 95%, intrinsic dark count rates
Michael Gaitan, Jon C. Geist, Benjamin J. Reschovsky, Akobuije Chijioke
We report on a new approach to characterize the performance of a laser Doppler vibrometer (LDV). The method uses two acousto-optic modulators (AOMs) to frequency shift the light from an LDV by a known quantity to create a synthetic velocity shift that is
Amber D. McCreary, Olga Kazakova, Deep Jariwala, Zakaria Al Balushi
The field of two-dimensional (2D) and layered materials continues to excite many researchers around the world who are eager to advance and innovate viable routes for large scale synthesis, doping and integration of monolayers and the development of unique
Lee J. Richter, Tommaso Nicolini, Jokubas Surgailis, Achileas Savva, Guillaume Wantz, Olivier Dautel, Georges Hadiziioannou, Natalie Stingelin
Organic mixed conductors find use in batteries, bioelectronics technologies, neuromorphic computing and sensing. While great progress has been achieved, polymer-based mixed conductors frequently experience significant volumetric changes during ion uptake
Dileep Reddy, Robert R. Nerem, Sae Woo Nam, Richard Mirin, Varun Verma
Superconducting nanowire single-photon detectors (SNSPDs) are an enabling technology for a myriad of quantum-optics experiments that require high-efficiency detection, large count rates, and precise timing resolution. The system detection efficiency (SDE)
Li-Anne Liew, David T. Read, May Martin, Frank W. DelRio, Peter E. Bradley, Nicholas Barbosa, Todd R. Christenson, John T. Geaney
The elastic-plastic properties of mesoscale electrodeposited LIGA Ni alloy specimens are investigated as a function of specimen size, strain rate, and material composition. Two material compositions are studied: a high-strength fine-grained Ni-Fe alloy and
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
Aurore F. Quelennec, Jason J. Gorman, Darwin Reyes-Hernandez
We present a label-free SAW-based flow sensor with enhanced precision and repeatability. This sensor improves the signal-to-noise ratio by one order of magnitude (dB scale) at an optimized frequency, and lowers the measurable flow rate to 5 μL/min (from
Clarence Zarobila, Steven Grantham, Steven W. Brown, John T. Woodward IV, Stephen Maxwell, Dana R. Defibaugh, Thomas Larason, Kevin Turpie
We have designed a non-imaging telescope for measurement of the spectral irradiance of the moon. The telescope was integrated into a wing pod of a NASA ER-2 research aircraft to measure lunar spectral irradiance during flight. The telescope and support
Seulki Cho, Son T. Le, Curt A. Richter, Arvind Balijepalli
We demonstrate that single-gated, commercially-sourced, field-effect transistors (FETs) operated with a lock- in amplifier (LIA) under closed-loop control can achieve an average pH resolution of 9x10^-4. This performance represents an 8-fold improvement