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Displaying 2076 - 2100 of 74084

Polydimethylsiloxane tissue-mimicking phantoms with tunable optical properties

July 1, 2022
Author(s)
Aaron Goldfain, Paul Lemaillet, David W. Allen, Kimberly Briggman, Jeeseong C. Hwang
We report on techniques to manufacture and characterize solid tissue-mimicking phantoms of polydimethylsiloxane (PDMS) polymers. Tunability of the absorption (a()) and reduced scattering spectra (s'()) in the wavelength range of 500 nm to 850 nm is

Spatiotemporal Monitoring of Melt-Pool Variations in Metal-Based Additive Manufacturing

July 1, 2022
Author(s)
Siqing Zhang, Yan Lu, Paul Witherell, Timothy Simpson, Soundar Kumara, Hui Yang
Additive manufacturing provides a higher level of flexibility to build customized products with complex geometries. However, AM is currently limited in its ability to ensure quality assurance and process repeatability. Advanced imaging provides unique

The Inner Shell Spectroscopy Beamline at NSLS-II: a facility for in situ and operando X-ray absorption spectroscopy for materials research

July 1, 2022
Author(s)
Bruce D. Ravel, Denis Leshchev, Bruno Luvizotto, Ruslan Kadyrov, Klaus Attenkofer, Eli Stavitski
Abstract The Inner Shell Spectroscopy (ISS) beamline on the 8-ID station at the National Synchrotron Light Source II (NSLS-II), Upton, NY, USA, is a high throughput X-ray Absorption Spectroscopy beamline designed for the in situ, operando, and time

Time-gated Raman spectroscopy of recovered plastics

July 1, 2022
Author(s)
Anthony Kotula, Sara Orski, Kayla Brignac, Jennifer Lynch, Bryan Heilala
Raman spectroscopy is a powerful non-destructive technique for the identification and characterization of plastics. The technique often has limited use due to fluorescence emission, which often occurs in polymer samples containing colorants or that have

Computational Study of the Allosteric Effects of p5 on the CDK5-p25 Hyperactivity as Alternative Inhibitory Mechanisms in Neurodegeneration

June 30, 2022
Author(s)
Tejaswi Tammareddy, Walid Keyrouz, Ram D. Sriram, Harish C. Pant, Antonio Cardone, Jeffery B. Klauda
The cyclin-dependent kinase (CDK5) forms a stable complex with its activator p25, leading to the hyperphosphorylation of tau proteins and to the formation of plaques and tangles that are considered to be one of the typical causes of Alzheimer's disease (AD

Report of the 105th & 106th National Conference on Weights and Measures

June 30, 2022
Author(s)
Shelby Bowers, Yvonne Branden, Tina G. Butcher, Richard A. Harshman, Gloria Diane Lee, David Sefcik, Lisa Warfield
The 105th Annual Meeting of the National Conference on Weights and Measures (NCWM) was held virtually July 12 - 16, 2020. The 106th Annual Meeting of the National Conference on Weights and Measures (NCWM) was held July 18 - 23, 2021, at the Hyatt Regency

Segmentation of Additive Manufacturing Defects Using U-Net

June 30, 2022
Author(s)
Vivian W. Wong, Max Ferguson, Kincho Law, Yung-Tsun Lee, Paul Witherell
Additive manufacturing (AM) provides design flexibility and allows rapid fabrications of parts with complex geometries. The presence of internal defects, however, can lead to the deficit performance of the fabricated part. X-ray computed tomography (XCT)

Self-Driven Highly Responsive PN Junction InSe Heterostructure Near-Infrared Light Detector

June 30, 2022
Author(s)
Chandraman Patil, Chaobo Dong, Hao Wang, Hamed Dalir, Sergiy Krylyuk, Huairuo Zhang, Albert Davydov, Volker Sorger
Photodetectors converting light signals into detectable photocurrents are ubiquitously in use today. To improve the compactness and performance of next-generation devices and systems, low dimensional materials provide rich physics to engineering the light

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
Displaying 2076 - 2100 of 74084