Search results for "Hard"

Fabrication and characterization of nanostructured Ni and Pd electrodes for hydrogen evolution reaction (HER) in water-alkaline electrolyzer

2017

In the field of water-alkaline electrolyzer, the development of nanoporous low cost nickel electrodes is one of the potential approaches to increase electrocatalytic activity. Template electrodeposition is a facile and cheap technique for obtaining Ni nanowires (NWs) with high surface area. These nanostructures were fabricated by a two-step procedure. In the first step, a Ni compact layer was deposited on one side of the template where a gold film was previously sputtered, while, in the second-step, an ordered array of Ni-NWs was obtained by electrodeposition inside the template channels. The NWs were firmly connected to the underlying Ni layer, acting as a current collector. In order to en…

Serial Production, Serial Photography, and the Writing of History in Three Farmers on Their Way to a Dance.

2010

Three Farmers on their Way to a Dance, titre d’une photographie qu’August Sander prit en 1914, hante le roman éponyme de Richard Powers. Cette photographie faisait partie d’un projet plus vaste, intitulé « Hommes du vingtième siècle » par Sander qui entendait dresser un inventaire des habitants de sa province natale, le Westerwald. Sander composa ainsi un catalogue de plus de 600 photos d’Allemands de tous types, dont il fit plus tard paraître une partie sous le nom de Visage de notre temps. Dans le roman de Richard Powers, le motif de la série se déploie entre les pôles incarnés par Henry Ford et August Sander, dont les séries de voitures et de photographies deviennent la métaphore du mode…

The cell nucleus. A study in Burgundy

2019

ABSTRACT Wilhelm Bernhard’s revolutionary microscopy techniques helped him put forward the hypothesis of specialized compartmentalization of the nucleus. He also described for the first time the nuclear bodies and peri-chromatin fibrils, and demonstrated that these granules contain an RNA component. The tradition of biennial workshops, named after this great scientist, continues, and this year it took place in the heart of Burgundy, in Dijon, France (May 20–24, 2019, organized by INSERM UMR1231, UBFC), where well-fed participants emphasized the importance of viewing the cell nucleus as a hub of specialized colloidal compartments that orchestrate replication, transcription and nuclear transp…

Modification of the Structure and Nano-Mechanical Properties of LiF Crystals Under Irradiation with Swift Heavy Ions

2011

The modifications of the structure and hardness of LiF crystals under high-fluence irradiation with MeV- and GeV-energy Au ions have been studied using nanoindentation and atomic force microscopy. The formation of ion-induced dislocations and bulk nanostructures consisting of grains with nanoscale dimensions (50 nm - 100 nm) has been observed. The structural modifications are accompanied by a strong ion-induced hardening which is related to dislocation impeding by assemblies of defect aggregates, dislocation loops of vacancy and interstitial types and grain boundaries. For MeV ions, the modifications are localized in a thin surface layer (few mm) where much higher density of deposited energ…

Growth and Electrochemical Performance of Lead and Lead Oxide Nanowire Arrays as Electrodes for Lead-Acid Batteries

2013

n this work, we present the growth and electrochemical performance of nanostructured lead and lead oxide electrodes for lead-acid batteries. The electrodes were obtained by template electrodeposition in polycarbonate membranes, acting as template. Electrochemical tests were conducted at constant current in 5M aqueous solution of sulphuric acid, after assembling nanostructured lead and lead oxide electrodes in a zero-gap configuration using a commercially available separator. The main advantages of these electrodes are the high specific energy and power density, and the wide surface area, about 70 times higher than the geometrical one. These features allowed high discharge rates, up to 20C. …

Design and development of safety and control systems in ATLAS

2021

El gran colisionador de hadrones, o LHC, es el acelerador de partículas más grande y potente del mundo. Ha sido construido por el CERN, la Organización Europea para la Investigación Nuclear, entre 1998 y 2008 en Ginebra, Suiza. Sucesivas mejoras en el LHC supondrán a partir de mediados del 2027 un incremento de la luminosidad, cuando pasará a llamarse High Luminosity LHC (HL-LHC). Esta tesis se divide en dos partes, por una parte la seguridad y operación de la infraestructura y por otra los sistemas de control y toma de datos. La primera parte de la tesis se dedica a la seguridad y operación de la infraestructura. Después de más de 10 años de funcionamiento, el riesgo de posibles fallos en …

Comparative chemical composition and bioactivity of leaves essential oils from nine Sicilian accessions of Myrtus communis L.

2019

In this study, the essential oils obtained from the leaves of Myrtus communis L. stored in a collection orchard located at the experimental station ‘Orleans’ of the Department of Agricultural and Forest Sciences of the University of Palermo (Italy) were investigated. The essential oils, analysed by gas chromatography–mass spectrometry, revealed the presence of α-pinene, 1,8-cineole, linalool, limonene and myrtenyl acetate as dominant constituents. The neuroprotective effects of M. communis essential oils were investigated by analysing the antioxidant properties and cholinesterases (acetylcholinesterase, AChE, and butyrylcholinesterase, BChE) inhibitory activity. Essential oils from Scopello…

Demokratia voittaa filosofian : Richard Rortyn uuspragmatismi poliittisena filosofoinnin tyylinä

1999

Les Evangiles de Suthard de Senones

1994

International audience

Hold-in, Pull-in and Lock-in Ranges for Phase-locked Loop with Tangential Characteristic of the Phase Detector

2019

In the present paper the phase-locked loop (PLL), an electric circuit widely used in telecommunications and computer architectures is considered. A new modification of the PLL with tangential phase detector characteristic and active proportionally-integrating (PI) filter is introduced. Hold-in, pull-in and lock-in ranges for given circuit are studied rigorously. It is shown that lock-in range of the new PLL model is infinite, compared to the finite lock-in range of the classical PLL. peerReviewed