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Displaying 2426 - 2450 of 74629

Thermal and mechanical properties of clathrate-II Na24Si136

June 30, 2022
Author(s)
Matthew Beekman, Antti Karttunen, Winnie Wong-Ng, Mingjian Zhang, Yu-Sheng Chen, Christian Posadas, Andrew Jarymowycz, Ethan Cruise, Wanyue Peng, Alexandra Zevalkink, James A. Kaduk, George S. Nolas
Thermal expansion, lattice dynamics, heat capacity, compressibility, and pressure stability of the intermetallic clathrate Na24Si136 have been investigated by a combination of first principles calculations and experiment. Direct comparison of the

Ultra-low Power Dual Frequency Comb Ranging

June 30, 2022
Author(s)
Emily Caldwell, Laura Sinclair, Jean-Daniel Deschenes, Nathan R. Newbury
Dual comb ranging is a well-established method of laser-based ranging that exploits frequency combs to provide absolute, high-precision measurements. It suffers, however, from a significant power penalty when compared with conventional FMCW LIDAR. Here, we

Application of machine learning to reflection high-energy electron diffraction images for automated structural phase mapping

June 29, 2022
Author(s)
Haotong Liang, Valentin Stanev, A. Gilad Kusne, Yuuto Tsukahara, Ama Itou, Ryota Takahashi, Mikk Lippmaa, Ichiro Takeuchi
We have developed a phase mapping method based on machine learning analysis of reflection high-energy electron diffraction (RHEED) images. RHEED produces diffraction patterns containing a wealth of static and dynamic information and is commonly used to

Fast Near-Infrared Photodetection using III-V Colloidal Quantum Dots

June 29, 2022
Author(s)
Lee J. Richter, Bin Sun, Amin M. Najarian, Chao Zheng, Laxmi K. Sagar, Min-Jae Choi, Xiyan Li, Larissa Levina, Se-Woong Baek, Seungjin Lee, Ahmad R. Kirmani, Jehad Abed, Mengxia Liu, Peicheng Li, Oleksandr Voznyy, Zheng H. Lu, F. Pelayo G. de Arquer, Edward H. Sargent
Colloidal quantum dots (CQDs) are promising materials for IR light detection due to their tunable bandgap and their solution processing; however, to date, the time response of CQD IR photodiodes has been inferior to that provided by Si and InGaAs. We

Heat Capacity Measurements of Conventional Aviation Fuels

June 29, 2022
Author(s)
Tara Fortin, Thomas Bruno
Isobaric specific heat capacities were measured for six conventional petroleum-derived aviation fuel samples: JP-10, JP-7, JP-4, JP-TS, TS-1, and Avgas. All measurements were made using modulated differential scanning calorimetry over the combined

Growth and Decomposition of Pt Surface Oxides

June 28, 2022
Author(s)
Feng Yi, Shane Arlington, Justin Gorham, William Alexander Osborn, Slavomir Nemsak, Ethan Crumlin, David A. LaVan
The formation and thermal stability of Pt surface oxides on Pt thin film were studied in situ using ambient pressure x-ray photoelectron spectroscopy (AP-XPS). AP-XPS allows us to monitor the chemical states of both adsorbed reactants and underlying

High-performance dual-gate graphene pH sensors

June 28, 2022
Author(s)
Son Le, Seulki Cho, Alexander Zaslavsky, Curt A. Richter, Arvind Balijepalli
High precision biophysical measurements that are portable and performed without prior labeling of the molecules can greatly benefit several areas of biotechnology and biophysics, but existing techniques often lack sufficient resolution. Field-effect

Integrating Multiple HLA Federations for Effective Simulation-Based Evaluations of CPS

June 28, 2022
Author(s)
Thomas Roth, Wenqi Guo, Chenli Wang, Himanshu Neema, Anirban Bhattacharjee
Cyber-Physical Systems (CPS) are complex systems of computational, physical, and human components integrated to achieve some function over one or more networks. The use of distributed simulation, or co-simulation, is one method often used to analyze the

Speed of Sound Measurements of Binary Mixtures of Hydrofluorocarbons [Pentafluoroethane (R-125), 1,1-Difluoroethane (R-152a), or 1,1,1,2,3,3,3-Heptafluoropropane (R-227ea)] with Hydrofluoroolefins [2,3,3,3-Tetrafluoropropene (R-1234yf) or trans-1,3,3,3-Te

June 28, 2022
Author(s)
Aaron Rowane, Richard A. Perkins
Speed of sound data measured using a dual-path pulse-echo instrument are reported for three binary refrigerant mixtures, R-125/1234yf, R-1234yf/152a, and R-1234ze(E)/227ea, at compositions of (0.33/0.67) and (0.67/0.33) mole fraction. The speed of sound

Development of a Hardware-in-the-loop Testbed for Laboratory Performance Verification of Flexible Building Equipment in Typical Commercial Buildings

June 27, 2022
Author(s)
Zhelun Chen, Jin Wen, Steven T. Bushby, Caleb Calfa, Yangyang Fu, Gabriel Grajewski, Yicheng Li, L. James Lo, Zheng O'Neill, Vance (Wm.) Payne, Amanda Pertzborn, Zhiyao Yang
The goals of reducing energy costs, shifting electricity peaks, increasing the use of renewable energy, and enhancing the stability of the electric grid can be met in part by fully exploiting the energy flexibility potential of buildings and building

Atomic Spectroscopy

June 25, 2022
Author(s)
William C. Martin, Wolfgang L. Wiese, Alexander Kramida
This chapter outlines the main concepts of atomic structure, with some emphasis on terminology and notation. Atomic radiation is discussed, in particular the wavelengths, intensities, and shapes of spectral lines, and a few remarks are made regarding

Broadband Dielectric Spectroscopic Detection of Ethanol: A Side-by-Side Comparison of ZnO and HKUST-1 MOFs as Sensing Media

June 25, 2022
Author(s)
Papa Amoah, Pentao Lin, Zeinab Mohammed Hassan, Rhonda Franklin, Engelbert Redel, Helmut Baumgart, Yaw S. Obeng
Changes in the chemo-electrical intrinsic properties of metal-oxide materials (MO) are commonly used as the basis of gas sensors. The most common gas sensors are based on chemically induced changes in electrical resistivity which necessarily involve making

Measurement Methods and Techniques for Pressure Losses in Pipe Fittings

June 25, 2022
Author(s)
Lingnan Lin, Marylia Duarte Batista, Natascha S. Milesi-Ferretti
Pressure losses in pipe fittings are important design information for sizing pipelines and selecting pumps. Currently, there is no standard method of test for determining the pressure loss of pipe fittings. To assist future development of a standard method
Displaying 2426 - 2450 of 74629