Search results for "ero"
showing 10 items of 33096 documents
Energy transfer in LH2 of Rhodospirillum Molischianum, studied by subpicosecond spectroscopy and configuration interaction exciton calculations.
2001
Two color transient absorption measurements were performed on a LH2 complex from Rhodospirillum molischianum by using several excitation wavelengths (790, 800, 810, and 830 nm) and probing in the spectral region from 790 to 870 nm at room temperature. The observed energy transfer time of ∼1.0 ps from B800 to B850 at room temperature is longer than the corresponding rates in Rhodopseudomonas acidophila and Rhodobacter sphaeroides. We observed variations (0.9-1.2 ps) of B800-850 energy transfer times at different B800 excitation wavelengths, the fastest time (0.9 ps) was obtained with 800 nm excitation. At 830 nm excitation the energy transfer to the B850 ring takes place within 0.5 ps. The m…
Asymptotic behavior of global solutions of aerotaxis equations
2019
Abstract We study asymptotic behavior of global solutions of one-dimensional aerotaxis model proposed in Knosalla and Nadzieja (2015) [9] .
Defect zero characters predicted by local structure
2017
Let $G$ be a finite group and let $p$ be a prime. Assume that there exists a prime $q$ dividing $|G|$ which does not divide the order of any $p$-local subgroup of $G$. If $G$ is $p$-solvable or $q$ divides $p-1$, then $G$ has a $p$-block of defect zero. The case $q=2$ is a well-known result by Brauer and Fowler.
First principles hybrid Hartree-Fock-DFT calculations of bulk and (001) surface F centers in oxide perovskites and alkaline-earth fluorides
2020
Valuable discussions with E. A. Kotomin are gratefully acknowledged. Research contribution of R. E. and A. I. P. has been performed within the framework of the EUROfusion Enabling Research project: ENR-MFE19.ISSP-UL-02 “Advanced experimental and theoretical analysis of defect evolution and structural disordering in optical and dielectric materials for fusion applications.” The views and opinions expressed herein do not necessarily reflect those of the European Commission.
Dynamic Consensus: Increasing Blockchain Adaptability to Enterprise Applications
2020
Decentralization powered by blockchain is validated for its capability to build trust like no other computational system before. The evolution of blockchain models has opened new use-cases that are becoming operational in many industry fields such as: energy, healthcare, banking, cross-border trade, aerospace, supply chain, and others. The core component of a decentralized architecture is the consensus algorithm - the set of rules that ensures an automated and fair agreement between the actors in the same network. Classic consensus algorithms are tailored to solve specific problems, but in an open ecosystem, each business case is unique and needs a certain level of customization. This paper…
Optical properties of GaSe, characterization and simulation
2021
Abstract The study focuses on structural and optical characterizations and properties of the GaSe lamellar material in one hand and on a numerical simulation of the photovoltaic properties of the ITO/GaSe heterojunction in a second hand. A few layers of GaSe were exfoliated from bulk GaSe on PET substrate. The optical transmission was recorded at room temperature. It shows that GaSe exhibits both indirect and direct band gaps of about 1.92 and 2.2 eV respectively. A value, as high as 104 cm−1, of the absorption coefficient was obtained. The corresponding refractive index has been determined numerically according to the Sellmeier and Cauchy models. The interesting value of absorption shows o…
Determining the deformation and resulting coupling efficiency degradation of ultrastable fiber-coupled optical benches under load.
2020
Fiber-coupled optical benches are an integral part of many laser systems. The base of such an optical bench is usually a slab of solid material, onto which optical components are fixed. In many environments, the ability to retain high fiber coupling efficiency under mechanical loads is essential. In this article, we study the fiber-to-fiber coupling efficiency under the application of static mechanical loads experimentally and theoretically: We constructed a simple three-point bending setup to interferometrically measure the deformation of an optical bench under load. Using the same setup, we further recorded the resulting coupling efficiency variations. The examined optical benches are bas…
Preparation, Characterisation and Dielectric Properties of YBa2Cu3O7-δ/ Insulator-Heterostructures
1996
YBa 2 Cu 3 O 7-δ /insulator/Au-heterostructures on SrTiO 3 or LaAlO 3 substrates were prepared to study the properties of the materials SrTiO 3 , BaTiO 3 and Ceo 2 . X-ray diffraction measurements in Bragg-Brentano geometry show c-axis-oriented growth for the superconductor and the insulators SrTiO 3 and CeO 2 . Typical values for the rocking curve width of the different insulating films are between 0.4° and 0.8°. The highest breakdown fields are measured for the insulator SrTiO 3 with +37.5 kV/mm and -8.8 kV/mm. The permittivity for CeO 2 is independent of applied field and only weakly temperature dependent. This is in contrast to the perovskite type insulators, where the permittivity depe…
Electron transport and the effect of current annealing in a two-point contacted hBN/graphene/hBN heterostructure device
2020
In this work, we fabricated a 2D van der Waals heterostructure device in an inert nitrogen atmosphere by means of a dry transfer technique in order to obtain a clean and largely impurity free stack of hexagonal boron nitride (hBN)-encapsulated few-layer graphene. The heterostructure was contacted from the top with gold leads on two sides, and the device’s properties including intrinsic charge carrier density, mobility, and contact resistance were studied as a function of temperature from 4 K to 270 K. We show that the contact resistance of the device mainly originates from the metal/graphene interface, which contributes a significant part to the total resistance. We demonstrate that current…
Laser Ultrasonics Inspection for Defect Evaluation on Train Wheel
2019
Abstract Passengers’ safety and in-service life of wheelset axles play an important role in railway vehicles. For this reason, periodic inspections are necessary. Among non-destructive techniques, ultrasonic ones are widely applied in this field. The main disadvantage of conventional ultrasonic techniques is that the overall inspection of wheels requires the train to be put out-of-service and disassembly each part, which is time-consuming and expensive. In this paper, a non-conventional non-contact laser ultrasonic inspection for train wheels is proposed. The proposed method uses a laser interferometer to receive the ultrasonic wave without contact. The receiving system allows choosing the …