Hydrogen cyanide in the headspace of oral fluid and in mouth-exhaled breath

Peer reviewe

Effect of moisture on the adsorption of ammonia

The effect of moisture on the adsorption of ammonia was systematically studied using different surface materials and humidity levels. The experimental water amount fractions varied between 6 and 18,000 mu molmol(-1), and the ammonia amount fraction was 400nmolmol(-1). The investigated materials included plain 316L stainless steel and stainless steel cured with Dursan, SilcoNert 2000 and halocarbon wax coatings. Furthermore, Teflon (PTFE) and polyvinylidene difluoride (PVDF) polymer surfaces were studied. Dynamically diluted ammonia, test tubes prepared with the investigated materials, a commercial ammonia analyzer based on cavity ring-down spectroscopy, and a commercial dew-point transmitter were employed. The adsorption was assessed quantitatively using continuous flow conditions and real-time monitoring of the adsorption process. The ammonia adsorption was found to increase substantially in dry conditions for all the studied materials except PVDF. The increase was largest for plain stainless steel which was the most adsorbing material. The coatings applied on stainless steel decreased the adsorption significantly in dry conditions. Polymers PVDF and PTFE were the least-adsorbing materials. In water amount fractions between 1000 and 10,000 mu mol mol(-1), the ammonia adsorption was at its lowest. The adsorption increased again above 1% humidity levels.Peer reviewe

Final publishable JRP summary for ENV55 MetNH3 - Metrology for Ammonia in Ambient Air

This project developed reference standards and measurement techniques for traceable measurements of NH3 in air. These will enable validated high quality ammonia measurement data which will help monitor and compare NH3 levels and ensure compliance with environmental protection policies and legislation

MetNH3: Metrology for Ammonia in Ambient Air

Measuring ammonia in ambient air is a sensitive and priority issue due to its harmful effects on human health and ecosystems. Ammonia is increasingly being globally acknowledged as a key precursor to atmospheric particulate matter. The European Directive 2001/81/EC on “National Emission Ceilings for Certain Atmospheric Pollutants (NEC)” regulates ammonia emissions in the member states. However, due to the chemical characteristics of ambient ammonia traceable on-line measurements still have significant challenges in analytical technology, uncertainty, quality assurance and quality control (QC/QA). Currently the UK National Ammonia Monitoring Network uses an accredited off-line low temporal resolution and on-line denuder–IC methods at the UK Supersites. There is a need for traceable ammonia measurements which will be vitally important for identifying changes in environment policies, climate and agricultural practice. This in turn should lead to improvements emission inventory uncertainties and for providing independent verification of atmospheric model predictions. MetNH3 (EMRP Joint Research Project) has worked with SMEs in testing improved reference gas mixtures by static and dynamic gravimetric generation methods, develop and refine existing laser based optical spectrometric standards and establishing the transfer from high-accuracy standards to field applicable methods. The first results from the metrological characterisation of a commercially available cavity ring-down spectrometer (CRDS) are presented and the results from a new design “Controlled Atmosphere Test Facility (CATFAC)”, which is currently characterising the performance of diffusive samplers. The range and characteristics of instruments are discussed. The plans for a major ammonia field intercomparison in 2016 will be outlined

Metrology for Ammonia in Ambient Air. Final publishable JRP report

This project developed reference standards and measurement techniques for traceable measurements of NH3 in air. These will enable validated high quality ammonia measurement data which will help monitor and compare NH3 levels and ensure compliance with environmental protection policies and legislation

High resolution photoacoustic overtone spectroscopy of monofluoroacetylene, HCCF, with a titanium:sapphire ring laser

Intracavity photoacoustic overtone spectrum of monofluoroacetylene, HCCF, has been recorded in the wave number region 10 750–14 500 cm−1 with a titanium:sapphire ring laser. The spectrum contains many dense vibration–rotation band systems which can be resolved with Doppler limited resolution. Altogether 58 individual overtone bands have been analyzed rotationally. Many of the observed bands show perturbations of which some have been attributed to anharmonic resonance interactions. A Fermi resonance model based on conventional rectilinear normal coordinate theory has been used to assign vibrationally bands from this work and from earlier studies. Many of the observed vibrational term values and rotational constants can be reproduced well with this model. The results show the importance of the Fermi resonance interactions at the high overtone excitations

L'expérimentation de l'approche LEADER en Hongrie et en République tcheque: Deux logiques poitiques différentes

The transfer of the local development model in the framework of the Common Agricultural Policy (2007-2013) implies learning a new form of public action based on initiatives borne by local stakeholders. One of the objectives of the LEADER Program is to improve the governance of rural areas through a bottom-up approach to local development. Are the conditions for carrying it out it in each country’s institutional context capable of boosting citizen participation in collective actions and consolidating local democracy? Defined and formulated at the EU level, the Leader approach has been transposed by member states in different ways and incorporated in each country’s system of local government in line with political strategies for establishing “action areas” that differ in their territorial coverage and articulation with institutional units. Empirical research sheds light on how local action groups have been shaped through the formation of partnerships and networks. The positions adopted by a few mayors on the local scene provide evidence of the emergence of a genuine political leadership