Search results for "OEL"

Measurements of Low-Energy Protons using a Silicon Detector for Application to SEE Testing

2021

A silicon detector with a fast electronics chain is used for the dosimetry of protons in the range 0.5-5 MeV at the Centro Nacional de Aceleradores (CNA) 3 MV Tandem laboratory in Seville, Spain. In this configuration, measurements can be performed in pulsed mode, using a digitizer to record event-by-event proton energy depositions. The distributions of deposited energy were obtained thanks to a calibration with an alpha source. Measurements of flux and deposited energy are used to enable single event effect (SEE) testing on selected static random access memories (SRAMs).

L'abbé Grégoire, son legs : six concours pour la liberté et l'égalité

2000

Gregoire's last will and testament called for the organization of six awards to be granted on the basis of written competitions on subjects that included reflections upon despotism, slavery, liberties, and equality, the themes of the struggles that had engaged Gregoire. Although the quality of the essays that resulted were not up to the level that the abbot had no doubt hoped for, the competition relative to the means of fighting the prejudice of color was the occasion to open a large debate and to launch the French abolitionist movement.

Ultrafast Interface Charge Separation in Carbon Nanodot-Nanotube Hybrids

2021

Carbon dots are an emerging family of zero-dimensional nanocarbons behaving as tunable light harvesters and photoactivated charge donors. Coupling them to carbon nanotubes, which are well-known electron acceptors with excellent charge transport capabilities, is very promising for several applications. Here, we first devised a route to achieve the stable electrostatic binding of carbon dots to multi- or single-walled carbon nanotubes, as confirmed by several experimental observations. The photoluminescence of carbon dots is strongly quenched when they contact either semiconductive or conductive nanotubes, indicating a strong electronic coupling to both. Theoretical simulations predict a favo…

Energy level determination of purine containing blue light emitting organic compounds

2018

Organic light emitting diodes (OLED) have found their applications in the mobile and TV screens. Till now the commercially available diodes are made by expensive thermal evaporation in a vacuum. The costs of OLED fabrication could be decreased by applying low-cost wet casting methods, for example, spin-coating. In this work, we have studied a group of blue light emitting purine derivatives which could potentially be used in OLEDs. The advantage of these compounds is their ability to form amorphous thin films from solutions. All the thin films were prepared by the spincoating method from chloroform solution on ITO glass. The position of hole and electron transport energy levels is important …

Burst analysis tool for developing neuronal networks exhibiting highly varying action potential dynamics

2012

In this paper we propose a firing statistics based neuronal network burst detection algorithm for neuronal networks exhibiting highly variable action potential dynamics. Electrical activity of neuronal networks is generally analyzed by the occurrences of spikes and bursts both in time and space. Commonly accepted analysis tools employ burst detection algorithms based on predefined criteria. However, maturing neuronal networks, such as those originating from human embryonic stem cells (hESCs), exhibit highly variable network structure and time-varying dynamics. To explore the developing burst/spike activities of such networks, we propose a burst detection algorithm which utilizes the firing …

Superconducting tunnel junction fabrication on three-dimensional topography based on direct laser writing

2020

Superconducting junctions are widely used in a multitude of applications ranging from quantum information science and sensing to solidstate cooling. Traditionally, such devices must be fabricated on flat substrates using standard lithographic techniques. In this study, we demonstrate a highly versatile method that allows for superconducting junctions to be fabricated on a more complex topography. It is based on maskless direct laser writing and two-photon lithography, which allows writing in 3D space. We show that high-quality normal metal–insulator–superconductor tunnel junctions can be fabricated on top of a 20-lm-tall three-dimensional topography. Combined with conformal resist coating m…

Actitudes y valores de los estudiantes universitarios ante los refugiados

2018

High Bias Voltage CZT Detectors for High-flux Measurements

2017

In this work, we present the performance of new travelling heater method (THM) grown CZT detectors, recently developed at IMEM-CNR Parma, Italy. Thick planar detectors (3 mm thick) with gold electroless contacts on CZT crystals grown by Redlen Technologies (Victoria BC, Canada) were realized, with a planar cathode covering the detector surface (4.1 x 4.1 mm(2)) and a central anode (2 x 2 mm(2)) surrounded by a guard ring electrode. The detectors, characterized by low leakage currents at room temperature (4.7 nA/cm(2) at 1000 V/cm), allow good room temperature operation even at high bias voltages (> 7000 V/cm). At low rates, the detectors exhibit an energy resolution around 4 % FWIEM at 59.5…

Spectral entropy based neuronal network synchronization analysis based on microelectrode array measurements

2016

Synchrony and asynchrony are essential aspects of the functioning of interconnected neuronal cells and networks. New information on neuronal synchronization can be expected to aid in understanding these systems. Synchronization provides insight in the functional connectivity and the spatial distribution of the information processing in the networks. Synchronization is generally studied with time domain analysis of neuronal events, or using direct frequency spectrum analysis, e.g., in specific frequency bands. However, these methods have their pitfalls. Thus, we have previously proposed a method to analyze temporal changes in the complexity of the frequency of signals originating from differ…

Biological and Proteomic Characterization of the Anti-Cancer Potency of Aqueous Extracts from Cell-Free Coelomic Fluid of Arbacia lixula Sea Urchin i…

2022

Echinoderms are an acknowledged source of bioactive compounds exerting various beneficial effects on human health. Here, we examined the potential in vitro anti-hepatocarcinoma effects of aqueous extracts of the cell-free coelomic fluid obtained from the sea urchin Arbacia lixula using the HepG2 cell line as a model system. This was accomplished by employing a combination of colorimetric, microscopic and flow cytometric assays to determine cell viability, cell cycle distribution, the possible onset of apoptosis, the accumulation rate of acidic vesicular organelles, mitochondrial polarization, cell redox state and cell locomotory ability. The obtained data show that exposed HepG2 cells under…