UN ECE Research Articles

Atmospheric Corrosion Effects of SO 2 and NO 2: A Comparison of Laboratory and Field‐Exposed Copper

Laboratory exposures of copper have been performed at exposure conditions comparable to those in the UN ECE exposure program with respect to air flow conditions, relative humidity, and concentration of the gaseous pollutants sulfur dioxide and nitrogen dioxide. Extrapolation of the weight increases in the laboratory experiments match well those obtained at the test sites with high sulfur dioxide and nitrogen dioxide pollution levels. At these sites, sulfate and nitrate were the dominating surface constituents, as in the laboratory exposures. Additional constituents, detected in the laboratory, but not in the field, were sulfite and nitrite. At test sites with low pollution levels of sulfur dioxide and nitrogen dioxide, weight increases were much higher than in the laboratory exposures. At these sites, sulfate and nitrate were detected, but the relative amount of nitrate was much lower compared to the sites with high levels of sulfur dioxide and nitrogen dioxide. However, the amount of sulfate was practically the same. In addition, was identified as an important compound at some sites. Characteristic of all sites with low pollution levels of nitrogen dioxide are the high levels of ozone. Ozone was not included in the laboratory experiments, which could explain the discrepancy in weight increase. Laboratory experiments, investigating the combined effects of sulfur dioxide and ozone are presented in another publication. Both chloride and ammonia were detected as surface constituents on all field samples, confirming that salts and/or gaseous pollutants, other than sulfur dioxide, nitrogen dioxide and ozone, also are important for the understanding of atmospheric copper corrosion. However, the present investigation does not focus on these pollutants.

Atmospheric Corrosion Effects of SO 2 and O 3 on Laboratory‐Exposed Copper

Copper samples were exposed for 10 days in synthetic laboratory air at 75% relative humidity. To explore the possible influence of ozone on the atmospheric corrosion rate of copper, various combinations of the gaseous pollutants sulfur dioxide, nitrogen dioxide, and ozone were added. Ozone promotes the oxidation of sulfur dioxide to sulfate more efficiently than nitrogen dioxide does. A synergism between sulfur dioxide and ozone is suggested. This synergism includes both the oxidation of sulfur dioxide by ozone and the capability of ozone to form oxides, hydroxides, or other oxygen‐containing reaction products in the presence of smaller amounts of sulfur dioxide. The synergistic effect possibly can explain the unexpectedly high corrosion rates of copper found at rural sites within the UN ECE exposure program. The rural sites are characterized by low sulfur dioxide and nitrogen dioxide concentrations, and by high ozone concentrations.

THE 1994 UN ECE SULPHUR PROTOCOL

Journal Article THE 1994 UN ECE SULPHUR PROTOCOL Get access R. R. Churchill, R. R. Churchill Search for other works by this author on: Oxford Academic Google Scholar G. Küutting, G. Küutting Search for other works by this author on: Oxford Academic Google Scholar L. M. Warren L. M. Warren *Cardiff Law School, University of WalesCardiff . This paper forms part of a study of international agreements for the protection of the atmosphere, funded under the ESRC Global Environmental Change programme Search for other works by this author on: Oxford Academic Google Scholar Journal of Environmental Law, Volume 7, Issue 2, 1995, Pages 169–197, https://doi.org/10.1093/jel/7.2.169 Published: 01 November 1995

The abatement strategies assessment model—ASAM: Applications to reductions of sulphur dioxide emissions across Europe

In May 1991 the 34 nations of the UN ECE region agreed that strategies for the abatement of SO 2 and NO x should be designed in the most cost-effective way, and that the concept of critical loads should serve as a guideline to formulate these strategies where science has provided the necessary information. The ASAM model has been developed in this context, as a computer tool to aid in guiding policy through investigation of the effectiveness of potential abatement strategies in Europe. In evaluating the environmental consequences, it takes into account the geographical distribution of emissions and the patterns of atmospheric transport and deposition; with the introduction of costs of reducing the different emissions, it provides a stepwise optimized approach to attaining specified target loads or critical loads for deposition across Europe, subject to flexible constraints in different countries. This paper describes the ASAM model, and work undertaken to establish the robustness of the model with regard to the assumptions made and uncertainties in the data used; and explores a range of scenarios currently being addressed.

Integrated lake monitoring in Europe the macrozoobenthos in the four target lakes in Finland

In four small (≤ 1 km2) Finnish lakes belonging to the Integrated Monitoring Programme (UN ECE), macrozoobenthos has been studied at different depths since 1989. The lakes are situated between 61°N–70°N latitudes from the southern boreal coniferous region up to the forest tundra ecotone. The macrozoobenthos of the lakes was very different compared to each other, but chironomids were important in all lakes. Acid-sensitive taxa (molluscs, some mayflies) were lacking in one of the lakes because of its low pH. In all lakes the zoobenthos could indicatee.g. the wideness of the littoral region and stagnation conditions or groundwater input through the bottom. In future, both litoral and profundal sampling is needed because of the multi-purpose character of the monitoring (acidification, trophic level).

Electronic Business and Banking — Which Security Aspects do Matter?

Business life is undergoing a profound change as our paper-based system of communicating is gradually replaced by electronic means. The new standards on Message Handling Systems X. 400 (CCITT 1988) and EDIFACT (Electronic Data Interchange for Administration Commerce and Trade, UN ECE/ ISO 1988 and later) create a unified framework for such applications.After giving examples of legally relevant communication possible security problems of using electronic mail or message handling systems (MHS) for banking, contracting, invoicing, and communication with administrations are discussed. Security in the context of the paper is defined to include legal and social as well as technical aspects. Results of a study done by the author comparing functional reliability and security of evidence of a typical MHS of today with paper-based conventional mail and Eurocheque are given.

Regions and French society: Three scenarios of the future

This paper is a translated version of the résumé, “Territoires et société”, of the report presented to the Budapest UN ECE seminar on long-term perspectives for human settlements development.