Floculation reversible de suspensions colloiedales (silice et latex) par des polymeres hydrosolubles

SIGLEINIST T 77094 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Metrological Needs for Monitoring Aquatic Environments: From the Demonstration of Metrological Traceability to the Decision Making Process

In Europe, the implementation of the Water Framework Directive WFD, in 2001, marks a strong standpoint. In addition to its objectives of a return to good chemical and good ecological status by the year 2015, it fixes the achievement of trends over space and time. The new requirements that arise from the WFD put considerable financial pressure on water management authorities. Because the overall decision-making process relies most of the time on acquired data, it puts considerable pressures on the display of high quality biological as well as chemical environmental measurements. However, performing measurements implies that i) the demonstration of their metrological traceability ii) the evidence of their achievement thanks to accurate and sensitive analytical methods and iii) their statement with a reliable estimate of expanded uncertainty is thoroughly addressed. Moreover, the measurement representativeness, especially in highly dynamic environment, is of prime interest in a context where comparability over space and time is needed. As a consequence, considerable challenges are dwelt on metrologists with great emphasis on parameters that are under regulation. This paper will discuss a panorama of the unavoidable metrological questions that have to be addressed: from the definition of the measurand to the final estimation of uncertainty; from the initial performances demonstration of methods to the final demonstration of mastery and capabilities through inter comparison laboratories and reference materials. A focus will be made on upcoming alternative monitoring approaches that are seldom addressed from a metrological point of view

Certified reference materials for breath alcohol control - the ALCOREF project

The Joint Research Project Alcoref “Certified forensic alcohol reference materials” is a multi-partner trans-national project within the targeted call “Research Potential” of the European Metrology Programme for Innovation and Research (EMPIR) launched in 2016. The European Commission has estimated that about one quarter of road traffic deaths are due to alcohol. The European status report on road safety of the World Health Organization Regional Office for Europe therefore stated that, among other measures, better legislation and enforcement of alcohol control is needed in several countries. In particular, the report demands that unrestricted access to alcohol breath testing, using breath analysers of equivalent and agreed standard, should be implemented throughout Europe. These high standards for tests, verification and calibration of breath alcohol analysers should meet some requirements of the recommendation R 126 defined by the International Organization of Legal Metrology (OIML) and European standards (EN 16280 and EN 15964). The specific objective of this project is to establish regional research and metrological capacity for the development of certified forensic alcohol reference materials for the law enforcement of drink-driving regulations

Metrological Characterization of an Aerosol Exposure Chamber to Explore the Inhalation Effects of the Combination of Paraquat and TiO2 Nano-objects

International audienceAgriculture emits a significant quantity of airborne contaminants, and the prospective environmental release of nanopesticides, a new type of agrochemical that employs engineered nanomaterials (ENMs) as either active substances or additives in a pesticide formulation, raises concerns about the risks of inhalation which are still unknown. Although the adverse effects of pesticides have been studied extensively, the potential synergistic toxicity between these substances and ENMs has rarely been investigated. To this end, toxicological models are essential to estimating the health consequences of such aerosols. Thus, to assess the respiratory hazards of titanium dioxide nano-objects (specifically, AEROXIDE (R) TiO2 P25 nanopowder [nTiO(2)]) in combination with paraquat (PQ), we developed a dynamic whole-body exposure chamber for rodents in compliance with guidelines for inhalation toxicity testing (Organization for Economic Cooperation and Development (OECD)) and animal welfare. First, we metrologically characterized the generated test aerosols by determining their mass and number concentrations, size distributions and atmospheric homogeneity at the laboratory. Then, we evaluated the reproducibility and proper functioning of the chamber during a preliminary field campaign, which validated the consistency of the aerosols' mass and number concentrations between the laboratory characterization and the rodent exposure sessions. Finally, we examined the inhalation effects on the rodents

Metrological Needs for Monitoring Aquatic Environments: From the Demonstration of Metrological Traceability to the Decision Making Process

In Europe, the implementation of the Water Framework Directive WFD, in 2001, marks a strong standpoint. In addition to its objectives of a return to good chemical and good ecological status by the year 2015, it fixes the achievement of trends over space and time. The new requirements that arise from the WFD put considerable financial pressure on water management authorities. Because the overall decision-making process relies most of the time on acquired data, it puts considerable pressures on the display of high quality biological as well as chemical environmental measurements. However, performing measurements implies that i) the demonstration of their metrological traceability ii) the evidence of their achievement thanks to accurate and sensitive analytical methods and iii) their statement with a reliable estimate of expanded uncertainty is thoroughly addressed. Moreover, the measurement representativeness, especially in highly dynamic environment, is of prime interest in a context where comparability over space and time is needed. As a consequence, considerable challenges are dwelt on metrologists with great emphasis on parameters that are under regulation. This paper will discuss a panorama of the unavoidable metrological questions that have to be addressed: from the definition of the measurand to the final estimation of uncertainty; from the initial performances demonstration of methods to the final demonstration of mastery and capabilities through inter comparison laboratories and reference materials. A focus will be made on upcoming alternative monitoring approaches that are seldom addressed from a metrological point of view

Étalons métrologiques fondamentaux

International audienceThe International System of Units (SI) adopted by the “Conférence générale des poids et mesures” in 1960 is the outcome of several decades of fruitful research in the setting-up of a consistent system of measurement units. The SI was designed so that in principle, any measurement of a physical or chemical quantity can be expressed as a number in some specified unit. Any quantity can be expressed by a combination of the seven base units of the SI. The definitions of the seven base units are presented with a short description of how they are used in practice. In addition, the particular case of units for ionizing radiation is presented, together with the principle of calibration chains.Le Système international d'unités (SI) qui a été adopté par la Conférence générale des poids et mesures en 1960 est l'aboutissement de plusieurs dizaines d'années de recherche fructueuses dans l'établissement d'un système logique d'unités de mesures. Le SI a été conçu afin que, en principe, chaque mesure d'une grandeur physique ou chimique puisse être exprimée par un nombre associé à une unité spécifique. Toute grandeur peut être exprimée par une combinaison de sept unités de base connues comme les unités de base du SI. Les définitions de ces sept unités de base sont présentées avec une courte description de la manière dont elles sont réalisées en pratique. De plus le cas particulier des unités pour les rayonnements ionisants est présenté ainsi que le principe des chaînes d'étalonnag