Atomistic to Circuit Level Modeling of Defective Doped SWCNTs with Contacts for On-Chip Interconnect Application

Carbon nanotubes (CNTs) due to their high electrical/thermal conductivity, high ampacity, high tolerance to electro-migration [1] and small dimensions make them an ideal candidate for future on-chip interconnects [2]. Fabricating the CNTs, random chirality and some defects are introduced which can degrade the CNT electrical properties [3]. Additionally, the contact resistance between metal and CNT presents additional parasitics that impose restraints on the electron transport. Electrical models of CNT for interconnect application were developed several years ago [4-5]. In this paper, we explored on doped and defective single-wall CNTs (SWCNT (24,0)) including contact resistance as important physical parameters to assess the performance of fabricated SWCNTs realistically for back-end-of-line (BEOL) on-chip interconnects on VLSI circuit application

Mise en oeuvre d'un outil d'alerte et de cartographie temps réel des aléas naturels liés aux précipitations dans les régions montagneuses et méditerranéennes du Sud-Est de la France

International audienceDue to its mountainous topography and its Mediterranean climate, the Provence-Alpes-Côte d'Azur (PACA) region in Southeastern France is particularly prone to flash floods, debris flows and mass movements (landslides and rockfall). A mapping system for these rainfall induced hazards has been tested by local and regional authorities and Government agencies since 2011 as part of the RHYTMME project. This system allows, thank to radar rainfall estimation and rainfall-runoff modelling, the real-time warning and monitoring of flash floods wherever they may occur in the PACA territory. It is also intended to enable, during intense rainfall events, the localisation of the streams susceptible to generate debris flows and of the slopes the more likely to trigger landslides and/or rockfalls

EURL-HM-22 Proficiency test report: Determination of total As, Cd, Pb, Hg, MeHg and inorganic As in fish

The European Union Reference Laboratory for Heavy Metals in Feed and Food (EURL-HM) organised a proficiency test (EURL-HM-22) for the determination of total As, Cd, Pb, Hg and inorganic As (iAs) in fish to support the Commission Regulation (EC) 1881/2006 setting maximum levels for certain contaminants in foodstuffs. This PT was open only to National Reference Laboratories (NRLs). The reference material "IAEA-436" (Tuna fish flesh homogenate) was used as test item. The finely ground dry powder material was rebottled, relabelled and dispatched to the participants. The reference values of interest were provided by the IAEA, together with an informative value for total Pb. The University of Graz (Austria) was requested to analyse the mass fraction of iAs in the material and reported a truncated value ("less than" 0.005 mg kg-1). Forty two participants from 30 countries registered to the exercise (all EU Member States plus Iceland and Norway). Only one participant could not report results due to technical instrumental problems. Laboratory results were rated using z- (z'- for MeHg) and zeta scores in accordance with ISO 13528:2015. The following relative standard deviations for proficiency assessment (σpt) were set according to the modified Horwitz equation: 13% for total Hg and MeHg; 15% for total As; and 22% for total Cd. No scoring was provided for total Pb and iAs. More than 92% of the participating NRLs reported satisfactory results (according to the z-score) for total As, Cd, Hg and MeHg, thus confirming their ability in monitoring the maximum levels set by the European Regulation (EC) No 1881/2006 for fish commodities. However, only 9 (out of 41) participants reported results for MeHg. Most of the laboratories provided realistic estimates of their measurement uncertainties.JRC.F.5-Food and Feed Complianc

Discrete bands of petroleum hydrocarbons and molecular organic markers identified within massive coral skeletons

The tissues of corals deposit an aragonite exoskeleton beneath their outer living film at a rate dependent on growth and hence on environmental conditions. This typically results in annual (seasonal) bands being formed within colonies. By analysing molecular organic markers within these bands, our research suggests that coral skeletons record contamination from oil and potentially could be used to investigate other anthropogenic and biogenic organic inputs. Our analyses of sections from within corals (Porites lutea) sampled from the Gulf coasts of Kuwait and Saudi Arabia demonstrate discrete bands of oil contamination which, using selected terpenoid biomarkers, can be source-indexed to specific oil fields (i.e. Kuwait, Iranian or Arabian crude oils). Together with dating using microscopic and X-ray inspection, this offers the potential to investigate contamination during recent years. Further research is, however, necessary to elucidate degradation mechanisms during, and following, the occlusion process of organics within coral skeletons

Energy autonomous wearable sensors for smart healthcare: a review

Energy Autonomous Wearable Sensors (EAWS) have attracted a large interest due to their potential to provide reliable measurements and continuous bioelectric signals, which help to reduce health risk factors early on, ongoing assessment for disease prevention, and maintaining optimum, lifelong health quality. This review paper presents recent developments and state-of-the-art research related to three critical elements that enable an EAWS. The first element is wearable sensors, which monitor human body physiological signals and activities. Emphasis is given on explaining different types of transduction mechanisms presented, and emerging materials and fabrication techniques. The second element is the flexible and wearable energy storage device to drive low-power electronics and the software needed for automatic detection of unstable physiological parameters. The third is the flexible and stretchable energy harvesting module to recharge batteries for continuous operation of wearable sensors. We conclude by discussing some of the technical challenges in realizing energy-autonomous wearable sensing technologies and possible solutions for overcoming them

Design and Selection of Buffers for Minimum Power-Delay Product

Using explicit modeling of delays we present and discuss real design conditions of CMOS buffers from the viewpoint of power dissipation. Efficiency of buffer implementation is first studied through the definition of limit for buffer insertion. Closed form alternatives to the design for minimum power-delay product are then proposed in terms of this limit. Validations are obtained through SPICE simulations on two stage inverter arrays. Applications are given to standard cell library in comparing implementations for different selection alternatives. 1. Introduction Driving buffers have been extensively used to control delays on combinatorial paths. Values of tapering factors were determined depending on the performance modeling level and on the physical representation of the cells involved with a common objective: minimizing the delay of paths. In an initial simple theory Lin and Linholm [1] introduced the fixed tapered buffer where the minimum propagation delay time is achieved when the..

Methylmercury formation in the anoxic waters of the Petit-Saut reservoir (French Guiana) and its spreading in the adjacent Sinnamary river

The present work was carried out on the hydroelectric reservoir Petit-Saut on the Sinnamary river in French Guiana. Measurements were performed during the wet and dry seasons along a longitudinal gradient, from upstream of the reservoir in two inflow rivers, to the Sinnamary estuary downstream of the dam. Gold extraction has led to a marked increase in suspended matter and total mercury (HgT) in one of the rivers. Dissolved monomethylmercury (MMHg) measured in surface waters were similar for both rivers: 0.03–0.05 ng l$^{-1}$ (1.0–1.7% of the dissolved HgT). These results indicate similar methylation efficiency and/or transfer of MMHg into the dissolved fraction of the water column, independently of the amounts of inorganic mercury transported. Dissolved MMHg concentrations in surface waters of the reservoir were similar to those in the rivers, but were more than 10 times higher in deep anoxie waters, up to 0.6 ng 1–1 (20% of dissolved HgT). The MMHg concentration profiles in the water column suggest that methylation occurs mainly in anoxie waters and sediments in relation with the activity of sulfate reducing bacteria. Dissolved MMHg concentrations measured in the Sinnamary at the base of the dam were still high (0.5–0.6 ng l$^{-1}$; 20 to 35% of the dissolved HgT).