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Analogy between Enzyme and Nanoparticle Catalysis: A Single-Molecule Perspective
Catalysis as a field is classically divided into three areas: homogeneous, heterogeneous, and biological catalysis.1 For the latter two, i.e., biological catalysis and heterogeneous catalysis, their dissimilarity can be apparent intuitively, from the scenes of fruit fermentation in a rural winery to make wine and oil refining in a process plant to produce gasoline. In addition to the practical differences, technological terms common in both areas show divergences in meaning. Here, a highly relevant example is the term turnover number.2 It refers to the maximum number of substrate molecules converted to products per enzyme molecule per second, often written as k cat in enzyme catalysis; while the same term means the number of moles of reactants that a mole of catalyst converts before deactivation, usually abbreviated as TON in heterogeneous catalysis.
Perovskite Na-ion conductors developed from analogous Li 3 x La 2/3− x TiO 3 (LLTO): chemo-mechanical and defect engineering
New Na-ion conductors Na 0.5 La 0.5 ZrO 3 and Na 0.25 La 0.25 Ba 0.5 ZrO 3 with expanded lattices were developed based on perovskite LLTO, successfully increasing the conductivities vs. unexpanded (Na,La)TiO 3 by up to ∼50×.
The Impact of Analog-to-Digital Converter Architecture and Variability on Analog Neural Network Accuracy
Not Available
Achieving Ideal Accuracies in Analog Neuromorphic Computing Using Periodic Carry.
Abstract not provided.
M32 analogs? A population of massive ultra-compact dwarf and compact elliptical galaxies in intermediate-redshift clusters
We report the discovery of relatively massive, M32-like ultra compact dwarf (UCD) and compact elliptical (CE) galaxy candidates in 0.2<z<0.6 massive galaxy clusters imaged by the Cluster Lensing And Supernova survey with Hubble (CLASH) survey. Examining the nearly unresolved objects in the survey, we identify a sample of compact objects concentrated around the cluster central galaxies with colors similar to cluster red sequence galaxies. Their colors and magnitudes suggest stellar masses around 10{sup 9}M{sub ⊙}. More than half of these galaxies have half-light radii smaller than 200 pc, falling into the category of massive UCDs and CEs, with properties similar to M32. The properties are consistent with a tidal stripping origin, but we cannot rule out the possibility that they are early-formed compact objects trapped in massive dark matter halos. The 17 CLASH clusters studied in this work on average contain 2.7 of these objects in their central 0.3 Mpc and 0.6 in their central 50 kpc. Our study demonstrates the possibility of statistically characterizing UCDs/CEs with a large set of uniform imaging survey data.
Correlation of analog solutions with experimental sea-level transient data for controlled turbine-propeller engine, including analog results at altitudes
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Validity of Using a Fixed Analog Input for Evaluating the SEU Sensitivity of a Flash Analog-to-Digita1 Converter
The SEU rate in a flash ADC (AD9058) on board a space experiment varied by more than an order of magnitude, depending on the input. A pulsed laser aided in elucidating the reasons, which were found to be the result of the unique design of the AD9058.
Validity of Using a Fixed Analog Input for Evaluating the SEU Sensitivity of a Flash Analog-to-Digital Converter
The SEU rate in a flash ADC (AD9058) on board a space experiment varied by more than an order of magnitude, depending on the input. A pulsed laser aided in elucidating the reasons, which were found to be the result of the unique design of the AD9058.
HERA Analog Lessons Learned Applicable to ISS as an Exploration Analog
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The Impact of Analog Computational Error on an Analog Boolean Satisfiability Solver
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Analog Systems for Edge Optimization
Over the past decade, analog computing has the subject of substantial research interest providing a path toward improved computational efficiency in the post-Dennard era. Analog matrix vector multiplication (MVM) accelerators provide a popular approach given the ubiquity of MVM operations in numerous applications. However, historically analog computing systems can struggle with applications requiring high precision due to the inherent susceptibility of these systems to analog non-idealities. Therefore, prior work on analog systems has focused either on applications known to be tolerant of limited precision (e.g., neural network inference), or using expensive techniques to emulate high-precision using many analog MVM operations. In this work, we propose an alternative approach. Motivated by recent advances in inexact nonlinear solvers and optimizers, we explore the potential of co-designing optimization algorithms which can take full advantage of the fundamentally inexact analog MVM operations. To enable these co-designed algorithms we also develop a general mathematical theory of the precision and energy efficiency of analog operations, and a new system architecture for tightly-coupled analog and digital computation. Finally, we examine the applicability of analog computing to a wider class of symmetric positive definite systems and find potential in using analog operations as a sparse approximate inverse preconditioner. With these core innovations, this project provides a path toward effectively implementing optimization algorithms on power-constrained autonomous and semi-autonomous systems.
LOCAL ANALOGS FOR HIGH-REDSHIFT GALAXIES: RESEMBLING THE PHYSICAL CONDITIONS OF THE INTERSTELLAR MEDIUM IN HIGH-REDSHIFT GALAXIES
We present a sample of local analogs for high-redshift galaxies selected in the Sloan Digital Sky Survey (SDSS). The physical conditions of the interstellar medium (ISM) in these local analogs resemble those in high-redshift galaxies. These galaxies are selected based on their positions in the [O iii]/Hβ versus [N ii]/Hα nebular emission-line diagnostic diagram. We show that these local analogs share similar physical properties with high-redshift galaxies, including high specific star formation rates (sSFRs), flat UV continuums, and compact galaxy sizes. In particular, the ionization parameters and electron densities in these analogs are comparable to those in z ≃ 2–3 galaxies, but higher than those in normal SDSS galaxies by ≃0.6 dex and ≃0.9 dex, respectively. The mass–metallicity relation (MZR) in these local analogs shows −0.2 dex offset from that in SDSS star-forming galaxies at the low-mass end, which is consistent with the MZR of the z∼2--3 galaxies. We compare the local analogs in this study with those in other studies, including Lyman break analogs (LBA) and green pea (GP) galaxies. The analogs in this study share a similar star formation surface density with LBAs, but the ionization parameters and electron density in our analogs are higher than those in LBAs by factors of 1.5 and 3, respectively. The analogs in this study have comparable ionization parameters and electron densities to the GP galaxies, but our method can select galaxies in a wider redshift range. We find the high sSFR and SFR surface density can increase the electron density and ionization parameters, but still cannot fully explain the difference in ISM condition between nearby galaxies and the local analogs/high-redshift galaxies.