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See detailMeasurement requirements for environmental monitoring : application of the electronic nose principle.
Nicolas, Jacques ULg; Romain, Anne-Claude ULg; Andre, Philippe ULg

Conference (2000)

As regards environment, the information to be provided to the decision maker or to the manager must be clear, accurate, unambiguous, and ideally it should be the result of the aggregation of a great ... [more ▼]

As regards environment, the information to be provided to the decision maker or to the manager must be clear, accurate, unambiguous, and ideally it should be the result of the aggregation of a great number of data or parameters. For example, the person in charge of the security of a municipality must have at his disposal an information of the type "all or nothing" to be able to decide if the population must be evacuated in the event of a severe pollution. However, that very simple information should be the result of a calculation based on several time series of pollutant concentration values and of meteorological data. Even the farmer who wants to know if it is the right time to spread manure without affecting too much the environment must have a single information which should be the aggregation of some complex variables. The lecture presents the concept of some "integrated index", already used to assess the quality of the environment. For example, Organic Pollution Index combines 4 laboratory measurement values of pollutants in water to make a single index characterising the global pollution in a river. Some apparatus are able to compute the integrated index "on line" and to supply directly to the user the value of the medium quality. For example, the PMV index estimates globally the thermal comfort in a building from the on line measurement of 5 parameters. FUL has designed some "smart sensors" or "smart instrument" aiming at supplying such index. Two applications are presented. The first one concerns the measurement of soil quality by means of a porous sensor combining in a single index the measurement of temperature, salinity and water contents. But the lecture develops particularly a second application which exploits the principle of the "electronic nose" to assess, in a single "signature", the quality or the intensity of an environmental odour. Such instrument, equipped with an array of "non specific" gas sensors, should be able, after a suitable learning phase, to recognise the odour source and to monitor it continuously in the field. The instrument response is thus a "pattern", similar to an integrated index, directly related to the annoyance, as felt by neighbouring people. It gives thus an information which can be handled by a manager, and which is more rich than individual pollutant concentration values. FUL has tested such instrument in the environment. The results are promising : a first design of electronic nose was able to recognise 5 odorous sources in the environment, and a portable instrument has been used to monitor the odour around a landfill site. The same concept is now tested to appraise as a whole the indoor air quality in different buildings. [less ▲]

Detailed reference viewed: 36 (10 ULg)
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See detailMeasurement uncertainty for persistent organic pollutants by isotope dilution mass spectrometry
Eppe, Gauthier ULg; Diletti, G; Fernandes, A et al

in Organohalogen Compounds (2014, September), 76

Detailed reference viewed: 39 (7 ULg)
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See detailMeasurement uncertainty for the analysis of serum 25-hydroxyvitamin D: response to Stepman and Thienpont
Cavalier, Etienne ULg; Delanaye, Pierre ULg; Cormier, Catherine et al

in Osteoporosis International (2010), 21

Detailed reference viewed: 45 (2 ULg)
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See detailMeasurement uncertainty of creatinine in low values: Another good reason not to use the MDRD formula with low creatinine values
Cavalier, Etienne ULg; Delanaye, Pierre ULg; Ferir, Anne-Marie et al

in Clinical Biochemistry (2007), 40(3-4), 285-286

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See detailMeasurement-induced spatial modulation of spontaneous decay and photon arrival times
von Zanthier, J.; Bastin, Thierry ULg; Agarwal, G. S.

in Physical Review. A (2006), 74

We report a way of manipulating the spontaneous emission process leading to a spatial modulation of spontaneous decay. The effect is observed in the case of coherently driven atoms separated by less than ... [more ▼]

We report a way of manipulating the spontaneous emission process leading to a spatial modulation of spontaneous decay. The effect is observed in the case of coherently driven atoms separated by less than a transition wavelength. It is quantified by Glauber's photon-photon second-order correlation function. We show that the photon arrival time, usually regarded as an entirely random process, depends not only on where a photon is detected but also on where a former photon had been recorded previously. Our results shed light on the unexpected consequences of state reduction and entanglement for the fundamental process of spontaneous emission. [less ▲]

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See detailMeasurement-induced spatial modulation of spontaneous decay and photon arrival times
von Zanthier, J.; Bastin, Thierry ULg; Agarwal, G. S.

Poster (2006)

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See detailMeasurement-induced spatial modulation of spontaneous decay and photon arrival times
von Zanthier, J.; Bastin, Thierry ULg; Agarwal, G. S.

Conference (2007)

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See detailMeasurements and modelization of light reflection on road pavement samples
Dijon, Jean-Marie; Embrechts, Jean-Jacques ULg; Brusten, Serge

in CIE Publication n°133 - Part 2 (1999)

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See detailMeasurements necessary for assessing the net ecosystem carbon budget of croplands
Smith, Pete; Lanigan, Gary; Kutsch, Werner L. et al

in Agriculture, Ecosystems & Environment (2010), 139(3), 302-315

There are a number of methods that can be used to help assess carbon budgets at the site to continental scales. Eddy covariance (EC) networks have been developed over the last decade and have been used to ... [more ▼]

There are a number of methods that can be used to help assess carbon budgets at the site to continental scales. Eddy covariance (EC) networks have been developed over the last decade and have been used to make many advances in our understanding. However, eddy covariance measurements of CO2 and water vapour exchanges quantify the fluxes only on short time scales, but do not assess the impacts of long-term processes that contribute to biogeochemical cycling in croplands, such as harvest or residue removal and other management practices, so many other supplementary measurements are required to attribute different components of the carbon flux. Such methods include isotope studies, chamber flux measurements of C and other greenhouse gases, inventories of above- and below-ground biomass as well as management in- and outputs, book-keeping modelling, process modelling, experimental manipulation and earth observation (e.g. remote sensing). In this review, we summarise the component fluxes that make up the total cropland carbon budget, describe the key fluxes and methods used to estimate them, and examine how they need to be integrated to obtain the net ecosystem carbon budget of European croplands. We describe the uncertainties and difficulties inherent at each stage and how these can be minimised. [less ▲]

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See detailMeasurements of air-ice CO2 fluxes over artificial sea ice emphasize the role of bubbles in gas transport
Kotovitch, Marie ULg; Moreau, Sébastion; Zhou, Jiayun et al

Poster (2015, March)

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See detailMeasurements of Column Abundances of Nitrogen Dioxide, NO2, from the Ground During the Globus-NOx Campaign
Zander, Rodolphe ULg; Demoulin, Philippe ULg; Roland, Ginette et al

in Bojkov, Rumen D.; Fabian, Peter (Eds.) Ozone in the Atmosphere, Proceedings of the Quadrennial Ozone Symposium 1988 and Tropospheric Ozone Workshop (1989)

Detailed reference viewed: 10 (2 ULg)
See detailMeasurements of EMG activity of pericranial muscles in tension-type headache
MAERTENS DE NOORDHOUT, Alain ULg; Schoenen, Jean ULg

in Olesen, J.; Schoenen, Jean (Eds.) Tension-Type Headache: classification, mechanisms and treatment (Frontiers in Headache Research) (1993)

Detailed reference viewed: 6 (3 ULg)
See detailMeasurements of HCFC-22 and validation update
Kolonjari, F.; Walker, K.A.; Mahieu, Emmanuel ULg et al

Scientific conference (2012, May 24)

This talk reports about global HCFC-22 measurements derived from ACE-FTS occultation observations recorded from 2004 onwards. It further provides information on the validation of ACE-FTS products for CFC ... [more ▼]

This talk reports about global HCFC-22 measurements derived from ACE-FTS occultation observations recorded from 2004 onwards. It further provides information on the validation of ACE-FTS products for CFC-11, -12 and HCFC-22 with ground-based FTIR instruments operated at four sites: Eureka, Poker Flat, Toronto and Jungfraujoch. [less ▲]

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See detailMeasurements of heat, water vapour and CO2 fluxes above a mixed forest
Aubinet, Marc ULg; Longdoz, Bernard; Yernaux, Michel et al

in Shimizu, H. (Ed.) Carbon dioxide and vegetation : Advanced approaches for absorption of CO2 and responses to CO2 (2001)

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See detailMeasurements of hindlimb blood flow recorded using Doppler ultrasound during administration of vasoactive agents in halothane-anesthetized horses
Raisis, Anthea L; Young, Lesley E; Meire, Hylton B et al

in Veterinary Radiology & Ultrasound : The Official Journal of the American College of Veterinary Radiology & the International Veterinary Radiology Association (2000), 41(1), 64-72

The purpose of the study was to determine the ability of Doppler ultrasound to detect changes in femoral blood flow during pharmacologic manipulation of arterial blood pressure. Doppler ultrasonography ... [more ▼]

The purpose of the study was to determine the ability of Doppler ultrasound to detect changes in femoral blood flow during pharmacologic manipulation of arterial blood pressure. Doppler ultrasonography was performed in the femoral vessels of six halothane-anesthetized horses before and during administration of phenylephrine HCI and sodium nitroprusside. The time-averaged mean velocity and volumetric flow were calculated. The contour of the velocity waveform was assessed, and the early diastolic deceleration slope (EDDS) and pulsatility index (PI) were calculated. Administration of phenylephrine HCI resulted in increased mean aortic blood pressure (MABP) by 40% (29.3-53.0%). This caused significant decrease in cardiac output (26.8 to 13.5 l/min), femoral arterial velocity (left artery 7.20 to 4.00 cm/s; right artery 5.01 to 3.39 cm/s) and volumetric flow (left artery 556 to 221 ml/min; right artery 397 to 193 ml/min) in the femoral vessels and significant increase in systemic vascular resistance (163 to 433 dyn-s/cm5), EDDS (1a: 285 to 468: ra: 250 to 481) and PI (1a: 9.38 to 20.4; ra 17.1 to 29.1). Administration of sodium nitroprusside resulted in a decreased MABP of 27.2% (22.5-33%). This increased cardiac output (20.8 to 32.4 L/min), however, no significant changes were observed in femoral blood flow. Despite obvious changes in the waveform contour, no significant change occurred in EDDS or PI. These results suggest that Doppler ultrasound may be useful for measuring femoral blood flow in anesthetized horses. However, waveform analysis appears to be limited when multiple changes occur in central and peripheral haemodynamics. [less ▲]

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See detailMeasurements of hydrogen cyanide (HCN) and acetylene (C2H2) from the Infrared Atmospheric Sounding Interferometer (IASI)
Duflot, V.; Hurtmans, D.; Clarisse, L. et al

in Atmospheric Measurement Techniques (2013), 6

Hydrogen cyanide (HCN) and acetylene (C2H2) are ubiquitous atmospheric trace gases with medium lifetime, which are frequently used as indicators of combustion sources and as tracers for atmospheric ... [more ▼]

Hydrogen cyanide (HCN) and acetylene (C2H2) are ubiquitous atmospheric trace gases with medium lifetime, which are frequently used as indicators of combustion sources and as tracers for atmospheric transport and chemistry. Because of their weak infrared absorption, overlapped by the CO2 Q branch near 720 cm−1, nadir sounders have up to now failed to measure these gases routinely. Taking into account CO2 line mixing, we provide for the first time extensive measurements of HCN and C2H2 total columns at Reunion Island (21° S, 55° E) and Jungfraujoch (46° N, 8° E) in 2009–2010 using observations from the Infrared Atmospheric Sounding Interferometer (IASI). A first order comparison with local ground-based Fourier transform InfraRed (FTIR) measurements has been carried out allowing tests of seasonal consistency which is reasonably captured, except for HCN at Jungfraujoch. The IASI data shows a greater tendency to high C2H2 values. We also examine a nonspecific biomass burning plume over austral Africa and show that the emission ratios with respect to CO agree with previously reported values. [less ▲]

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See detailMeasurements of long-term changes in atmospheric OCS (carbonyl sulfide) from infrared solar observations
Rinsland, Curtis P.; Chiou, Linda S.; Mahieu, Emmanuel ULg et al

in Journal of Quantitative Spectroscopy & Radiative Transfer (2008), 109(16), 2679-2686

Multi-decade atmospheric OCS (carbonyl sulfide) infrared measurements have been analyzed with the goal of quantifying long-term changes and evaluating the consistency of the infrared atmospheric OCS ... [more ▼]

Multi-decade atmospheric OCS (carbonyl sulfide) infrared measurements have been analyzed with the goal of quantifying long-term changes and evaluating the consistency of the infrared atmospheric OCS remote-sensing measurement record. Solar-viewing grating spectrometer measurements recorded in April 1951 at the Jungfraujoch station (46.5°N latitude, 8.0°E longitude, 3.58 km altitude) show evidence for absorption by lines of the strong ν3 band of OCS at 2062 cm(−1). The observation predates the earliest previously reported OCS atmosphere remote-sensing measurement by two decades. More recent infrared ground-based measurements of OCS have been obtained primarily with high-resolution solar-viewing Fourier transform spectrometers (FTSs). Long-term trends derived from this record span more than two decades and show OCS columns that have remained constant or have decreased slightly with time since the Mt. Pinatubo eruption, though retrievals assuming different versions of public spectroscopic databases have been impacted by OCS ν3 band line intensity differences of 10%. The lower stratospheric OCS trend has been inferred assuming spectroscopic parameters from the high-resolution transmission (HITRAN) 2004 database. Volume mixing ratio (VMR) profiles measured near 30°N latitude with high-resolution solar-viewing FTSs operating in the solar occultation mode over a 22 years time span were combined. Atmospheric Trace MOlecucle Spectroscopy (ATMOS) version 3 FTS measurements in 1985 and 1994 were used with Atmospheric Chemistry Experiment (ACE) measurements during 2004–2007. Trends were calculated by referencing the measured OCS VMRs to those of the long-lived constituent N2O to account for variations in the dynamic history of the sampled airmasses. Means and 1-sigma standard deviations of VMRs (in ppbv, or 10−9 per unit air volume) averaged over 30–100 hPa from measurements at 25–35°N latitude are 0.334±0.089 ppbv from 1985 (ATMOS Spacelab 3 measurements), 0.297±0.094 ppbv from 1994 ATLAS 3 measurements, 0.326±0.074 ppbv from ACE 2004 measurements, 0.305±0.096 ppbv from ACE 2005 measurements, 0.328±0.074 from ACE 2006 measurements, and 0.305±0.090 ppbv from ACE measurements through August 2007. Assuming these parameters, we conclude that there has been no statistically significant trend in lower stratospheric OCS over the measurement time span. We discuss past measurement sets, quantify the impact of changes in infrared spectroscopic parameters on atmospheric retrievals and trend measurements, and discuss OCS spectroscopic uncertainties of the current ν3 band parameters in public atmospheric databases. [less ▲]

Detailed reference viewed: 44 (9 ULg)
See detailMeasurements of mediator cascades during adult respiratory distress syndrome
Lamy, Maurice ULg; Deby-Dupont, G.; Deby, C. et al

in Adult Respiratory Distress Syndrome (1992)

Detailed reference viewed: 5 (1 ULg)