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Edwin J. Heilweil, Amber Meyers, Christopher J. Stromberg
Two anionic asymmetric Fe-Fe Hydrogenase model compounds containing a single CN and five CO ligands: [Fe2(μ-S2C3H6)(CO)5(CN)1]1− (1) and [Fe2(μ-S2C2H4)(CO)5(CN)1]1− (2) dissolved in room temperature acetonitrile are examined. The molecular asymmetry
Erin Adkins, David Long, Adam Fleisher, Joseph T. Hodges
Frequency-agile rapid scanning, cavity ring-down spectroscopy (FARS-CRDS) was used to measure line intensities and line shape parameters of 14N216O in air in the (4200)←(0000) and (5000)←(0000) bands near 1.6 μm. The spectra were analyzed with multi
William Sparks, M. N. Parenteau, Robert E. Blankenship, Thomas Germer, C.H. L. Patty, Kimberly M. Bott, Charles M. Telesco, Victoria S. Meadows
Photosynthesis is an ancient metabolic process that began on the early Earth, offering plentiful energy to organisms that utilize it, to the extent that they can achieve global significance. The potential exists for similar processes to operate on
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
We have succeeded in operating a transition-edge sensor (TES) spectrometer and evaluating its performance at the SPring-8 synchrotron x-ray light source. The TES spectrometer consists of a 240 pixel National Institute of Standards and Technology (NIST) TES
Infrared (IR) absorption spectroscopy is a powerful tool that can quantify complex biomolecules and their structural conformations. However, conventional approaches to protein analysis in aqueous solutions have been significantly challenged because the
Kevin Cossel, Eleanor M. Waxman, Esther Baumann, Fabrizio Giorgetta, Brian Washburn, Caroline Alden, Sean Coburn
Open-path dual-comb spectroscopy (DCS) is an emerging technique for long open-path measurements across km-scale paths. It provides both broad spectral coverage over hundreds of wavenumbers with high spectral resolution and negligible instrument lineshape
Adam J. Sirois, Manuel C. Castellanos Beltran, Anna E. Fox, Samuel P. Benz, Peter F. Hopkins
Quantum computers with thousands or millions of qubits will require a scalable solution for qubit control and readout electronics. Colocating these electronics at millikelvin temperatures has been proposed and demonstrated, but there exist significant
James Maslar, William A. Kimes, Brent A. Sperling, Ravindra K. Kanjolia
Low volatility precursors are widely utilized in chemical vapor deposition (CVD) and atomic layer deposition (ALD) processes. Compared to gases and high volatility liquid precursors, delivery of low volatility liquid and solid precursors can be problematic
Abneesh Srivastava, Stephen E. Long, James E. Norris, Colleen E. Bryan Sallee, Jennifer Carney, Joseph Hodges
We present a direct comparison between two independent methods for the measurement of gaseous elemental mercury (GEM) mass concentration: isotope dilution cold-vapor inductively coupled plasma mass spectrometry (ID-CV-ICP-MS) and laser absorption
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
M. D. Yoho, K. E. Koehler, Dan Becker, Douglas Bennett, M. H. Carpenter, M. P. Croce, J. D. Gard, John Mates, D. J. Mercer, Nathan Ortiz, Dan Schmidt, C. M. Smith, Daniel Swetz, A. D. Tollefson, Joel Ullom, Leila R. Vale, Abigail Wessels, D. T. Vo
Photon branching ratios are critical input data for activities such as nuclear materials protection and accounting because they allow material compositions to be extracted from measurements of gamma-ray intensities. Uncertainties in these branching ratios
Marat Andreev, David Nicholson, Anthony Kotula, Jonathan D. Moore, Jaap Den Doelder, Gregory C. Rutledge
Polymer crystallization occurs in many plastic manufacturing processes, from injection molding to film blowing. Linear low-density polyethylene (LLDPE) is one of the most commonly processed polymers, wherein the type and extent of short chain branching
Ultrafast Time-Domain and Time-Resolved Terahertz (TDS/TRTS) spectroscopic methods are utilized to explore photoconductive properties of conjugated donor-acceptor co-polymers dispersed in room temperature toluene, a nonpolar dielectric solvent. TRTS
Joel Weber, Kelsey Morgan, Daikang Yan, Christine Pappas, Abigail Wessels, Galen O'Neil, Douglas Bennett, Gene C. Hilton, Daniel Swetz, Joel Ullom, Daniel Schmidt
Transition-edge sensors (TESs) are thermal detectors in which a superconducting film that is electrically biased in the superconducting-to-normal transition is used as a thermometer. In most TESs, the film is a superconductor-normal metal bilayer where the
Yaw S. Obeng, Papa K. Amoah, Christopher E. Sunday, Jesus Perez, Uros Cvelbar, Martin Kosicek
Contactless broadband microwave spectroscopic technique (a.k.a., broadband dielectric spectroscopy (BDS)) enables the accurate operando analysis of the electrical and magnetic properties applying without compromising the kinetic conditions of the
Parker J. Nichols, Alexandra Born, Morkos A. Henen, Dean Strotz, David N. Jones, Frank Delaglio, Beat Vogeli
We have previously reported on the measurement of exact NOEs (eNOEs), which yield a wealth of additional information in comparison to conventional NOEs. We have used these eNOEs in a variety of applications, including calculating high-resolution structures
Galen O'Neil, Samuel C. Sanders, Paul Szypryt, Dipti Goyal, Amy Gall, Yang Yang, Samuel M. Brewer, William Doriese, Joseph Fowler, Daniel Swetz, Joseph Tan, Joel Ullom, Andrey V. Volotka, Endre Takacs, Yuri Ralchenko
Quantum electrodynamics (QED) is currently considered to be one of the most accurate theories of fundamental interactions. As its extraordinary precision offers unique scientific opportunities, e.g., search for new physics, stringent experimental tests of
Jeeseong Hwang, Christopher S. Yung, Ruimin Chen, Yun He, Junhui Shi, Lihong Wang, Qifa Zhou
We report the development of an optically transparent high-frequency ultrasonic transducer using lithium niobate single-crystal and indium-tin-oxide electrodes with up to 90 % optical transmission in the visible to near infrared spectrum. The center
We describe an algorithm to extract the complex refractive index of a material from reflectance and transmittance measurements commonly taken by spectrophotometers. The algorithm combines Kramers- Kronig analysis with an inversion of Fresnel's equations to
Amber D. McCreary, Thuc T. Mai, Franz Utermohlen, Jeffrey R. Simpson, Kevin F. Garrity, Xiaozhou Feng, Dmitry Shcherbakov, Yanglin Zhu, Jin Hu, Daniel Weber, Kenji Watanabe, Takashi Taniguchi, Joshua Goldberger, Zhiqiang Mao, Chun Ning Lau, Yuanming Lu, Nandini Trivedi, Rolando Valdes Aguilar, Angela R. Hight Walker
The discovery of 2-dimensional (2D) materials, such as CrI3, that retain magnetic ordering down to monolayer thickness, and even more have layer-dependent magnetic properties has led to a plethora of research in 2D magnetism. Here, we report a magneto