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Abstract  

Thermal and epithermal neutron activation analysis techniques were used to analyze 27 Teflon air filters which were exposed to ambient air in Lisbon, Portugal, in February 2007. Tin was detected which is strongly suggestive of an anthropogenic source. Arsenic, antimony and copper were shown to be highly correlated, which is also suggestive of anthropogenic pollution. Trace element analysis of short- and medium-lived isotopes was performed yielding concentration information of various elements. Analytical sensitivities were enhanced using a Compton suppression system. Enrichment factor analysis shows that arsenic, tin, zinc, copper and antimony are at elevated concentrations in the Lisbon atmosphere.

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Abstract  

The application of pulse radiolysis to the measurement of rates of reaction of aromatic and olefinic radical anions in organic solvents is discussed, emphasis being placed on the problem of reaction of the radical anion with the radiolytically-generated-counter ion. Some previous experiments of the authors that utilised tetrahydridoaluminate salts to scavenge the counter ion are reviewed. Some new data on the rates of electron transfer from aromatic-radical anions to some substituted styrenes are presented and experiments aimed at using organic amides as solvents for these studies are described.

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Plant biomass production, soil chemical and microbial parameters, microbial processes of C and N cycle and gases emissions were studied in soils at two types of grasslands (wet meadows). Both sites are situated in the Czech Republic: (1) a nutrient poor sedge meadow on organic soil (Z) and (2) a mesotrophic sedge-sweet grass meadow on mineral soil (H). Eutrophication was simulated by the application of NPK fertilizer to selected permanent plots in 2006 and 2007 in amounts of 9 kg N + 4 kg P ha −1 year −1 (low dose) and 45 kg N + 20 kg P ha year (high dose). After two years of fertilizer application, we observed an increase in net aboveground plant production (about 9–12 kg ha −1 year ) connected with an increase in shoot:root ratio in fertilized plots of both sites, with more pronounced changes in oligotrophic sedge meadow. Total CO 2 efflux from the ecosystem measured in situ was significantly higher at fertilized plots as well as increase in total soil respiration in case of sedge meadow, but we found no significant effect of fertilization on CO 2 efflux from the system at mesotrophic site. Surprisingly, other parameters, like soil microbial biomass C and N content, the rates of respiration, denitrification, nitrification, nitrogen mineralization and nitrogen assimilation were not affected by fertilization. In conclusion, an interesting finding is that despite non significant impact on aboveground component there were significant responses in belowground part which suggest that belowground processes may be suitable early warning signals. Peaty oligotrophic soil seems to be more sensitive to nutrient addition than mineral soil. However, final effect of fertilization on ecosystem C balance stays unknown and longer study is necessary to draw explicit conclusion.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: S. Goheen, B. McVeety, T. Clauss, R. Lucke, M. Ligotke, J. Edwards, and J. Fruchter

Abstract  

Organic species from the headspace of one Hanford radioactive waste tank are described. Samples were collected either using a sorbent trap or a SUMMATM canister and were analyzed by gas chromatograph and mass spectrometry. The headspace contained several organic components, including alkanes, alkenes, ketones, aldehydes, organic nitriles, and chlorinated hydrocarbons. Sorbent trap samples were designed to collect only normal paraffin hydrocarbons (NPHs). A comparison of NPH data from sorbent traps and SUMMATM cans revealed results of 693 and 1320 mg/m3, NPH respectively. Significant differences were observed in NPH values when samples were collected at different times, or at different locations in the tank. These data suggest either the time of collection, or the position of the sampling device are important variables in the analysis of organic species from Hanford tanks.

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The Hungarian plant protection organization has been performing western corn rootworm moni- toring over the past four years.In 1998 three different trapping activities were carried out at 150 monitoring sites.Hungarian pheromone traps and Multigard ®(yellow sticky)traps were used from July 1 to September 30.The number of catches and the average catches/trap in 1998 were lower than the catch numbers in 1997. In 1998,the pest spread to a lesser degree than in 1997.

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WCR adults generally lay their eggs in maize and their larvae feed almost exclusively on maize roots (Smith,1966,Branson and Ortman,1967,1971,Branson and Krysan,1981,Levine and Oloumi- Sadeghi,1991).For this reason,farmers have accepted growing maize in rotation with soybean to manage WCR larval populations without the use of soil insecticides.Recently,in Northwest Indiana and East Central Illinois in the USA,western corn rootworm has adapted to the above management system (Gerber et al., 1997).A portion of WCR eggs is laid in soybean and in other crops like alfalfa.This behavioral change increases the potential for survival of WCR larvae the following year since most soybean fields are rotated to maize.During the summers of 1996,1997,and 1998 field studies related to this behavioral shift were conducted in northwestern Indiana.Eleven pairs of maize/soybean fields were selected for the study.During these sampling periods,WCR beetles were present in both maize and soybean.Empirical observations show that there were higher numbers of females in soybean when compared to maize.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: E. Hoppe, E. Mintzer, C. Aalseth, D. Edwards, O. Farmer, J. Fast, D. Gerlach, M. Liezers, and H. Miley

Abstract  

Copper is one of few elements that have no long-lived radioisotopes and which can be electrodeposited to ultra-high levels of purity. Experiments probing neutrino properties and searching for direct evidence of dark matter require ultra-clean copper, containing the smallest possible quantities of radioactive contaminants. Important to the production of such copper is establishing the location and dispersion of contamination within the bulk material. Co-deposition of contaminants during copper electrodeposition and its relationship to nucleation and growth processes were investigated using scanning electron microscopy (SEM), laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), and secondary ionization mass spectrometry (SIMS).

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A Food and Agriculture Organization of the United Nations Technical Cooperation Programme (TCP)was undertaken on the western corn rootworm (WCR)in 1997 –1998 to establish a permanent moni- toring network,evaluate a containment and control program,test the feasibility and effectiveness of using a Slam ®-based areawide pest management program,develop training materials,and conduct a risk assessment of the potential for WCR spread and establishment in other areas of Europe.TCP countries were Bosnia-Her- zegovina,Croatia,Hungary,and Romania.Bulgaria and Yugoslavia cooperated as unofficial TCP members. The data from the permanent monitoring network showed that the WCR had spread over an area of about 105,600 km 2 in Central Europe and that economic populations had developed on 14,000 km 2 in Yugoslavia through 1998.The containment and control trapping program,although designed to determine the feasibility of restricting the establishment of WCR beetles in an area,did not prove to be successful due to the number of WCR beetles encountered and their rapid movement into previously uninfested areas.The areawide pest management activity showed that the semiochemical Slam was highly efficacious against WCR beetles with residual activity for up to 2 weeks,thus making it a cost-effective alternative to other controls.Also, investigations showed that WCR will continue to spread and establish in other parts of Europe.

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