Mjerenja ozona na brdu Srđ blizu Dubrovnika, Hrvatska

Results and analysis of ozone monitoring at station Sr| (46.25° N, 17.45° E, 412 m a.s.l.) near Dubrovnik from 1998 – 2005 are reported. It is confirmed that this is an unpolluted place despite of high summer solar radiation which could contribute to the photochemical air pollution formation. There is no significant trend in ozone levels found during this time and the overall aver­age ozone fraction is found to be 46 ppb for the summer periodsPrikazani su rezultati i analiza mjerenja ozona na postaji Srđ (46.25° N, 17.45° E, 412 m a.s.l.) blizu Dubrovnika u razdoblju od 1998 do 2005. Potvrđen je neonečišćeni karakter ove lokacije unatoč jakom Sunčevom zračenju ljeti. Mjerenja nisu dala naznake trenda u koncentracijama ozona, a prosječna vrijednost udjela ozona u ljetnom periodu je bila 46 ppb

Mjerenja ozona na planinskoj postaji Zavižan (Hrvatska) tijekom 1997. – 2000.

Analysis of ozone concentrations measured at Zavižan, Croatia\u27s highest altitude meteorological station (1594 m a.s.l.), during the spring and summer months of 1997–2000 shows that the actual new Croatian Air Quality standards are severely exceeded. Implication of this and similar findings from other elevated sites call for additional consideration of ozone behaviour at high altitudes in defining ozone standards.Analiza podataka o volumnom udjelu ozona na Zavižanu, najvišoj meteorološkoj postaji u Hrvatskoj (1594 m iznad mora) tijekom proljeća i ljeta 1997. do 2000. godine pokazuje da vrijednosti znatno prelaze granične vrijednosti za kvalitetu zraka važeće nove hrvatske Uredbe o ozonu. Dobiveni rezultati i mjerenja s drugih visinskih postaja ukazuju da potrebu razmatranja uvjeta i na visinskim postajama pri definiranju graničnih vrijednosti za kvalitetu zraka s obzirom na ozon

Trends, Distribution and Frequency Analysis of Ozone Data from Three Monitoring Stations in Baton Rouge, Louisiana for the Years 1995 to 2005

Troposphere ozone concentrations exhibit pronounced, characteristic diurnal and seasonal cycles. These cycles are usually well defined. However, additional oscillations also occur; these are generally much smaller in amplitude than the 1-day or 1-year cycles and they might be attributable to anthropogenic influences (e.g., specific man-induced meteorological and chemical influences on an individual monitoring station, periodic maintenance activities, etc.). Indeed, it is possible that the spectral analysis of photochemical pollution data could pinpoint hidden conditions that affect particular monitoring stations. Such an analysis, one based on Fourier transform methods, was applied to long-term data from 3 American monitoring stations. As would be expected, strong signals were found for the 1-day and 1-year periods; however, some weaker signals, ones probably associable with anthropogenic affairs, were also observed. A principal component analysis (PCA) was applied to the transformed data sets in order to identify these periods. Periods of 3.5-days and 7-days, as well as a number of other cycles, were found and can be considered to be markers of anthropogenic influences. European and American data will be compared and the effects of Hurricane Katrina will be examined

Gas phase kinetics of metal ion ligation by pyrene

Investigation of simple ligation reactions of metal M+ ions with pyrene (Py) within the ICR FT mass spectrometer indicates relatively fast consecutive formation of MPy+ and MPy2+ ions, and if E-i(M+) > E-i(Py) accompanied also by formation of Py+ due to charge exchange. The much slower reaction and equilibrium Py+ + Py reversible arrow Py-2(+), for which the thermodynamic parameters are known, makes it possible to determine the concentration of Py during the ligation reactions and to calculate the second order rate constants from the set of pseudo first order constants obtained by iterative nonlinear least square fitting of experimental snapshot mass spectral data with the proposed kinetic scheme

Long-term Ozone Data Analysis

Various approaches to the analysis of 10-year continuous ozone mo-nitoring from the EUROTRAC-TOR network station Puntijarka near Zagreb are reported. The site has a rural character (45.90° N; 15.97° E, 980 m a.s.l.) and is representative of the lower troposphere of a wider region. Mean hourly ozone volume fractions measured from 1990-1999, autocorrelation plots for ali data and for data for summer periods (May-Sep.), box and whiskers representations of diurnal variations during winter (Nov.-March) and summer periods, mean monthly values and 12-month moving averages, and the Fourier transform of the complete set of 94,248 hourly mean ozone volume fractions are discussed. The data show no increase, or possibly a slight decrease, of the ozone volume fraction toward the end of the decade

Role of Nitrogen Oxides in Ozone Toxicity

The preparation of ozone/nitrogen oxides mixtures in air containing the nitrate radical, their reaction with the unsaturated lipid 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC), and the determination of the reaction products in comparison to those obtained from a reaction with only ozone in air by MALDI-FTMS is described. The results indicate the importance of nitrate radical in ozone toxicity

Role of Nitrogen Oxides in Ozone Toxicity

The preparation of ozone/nitrogen oxides mixtures in air containing the nitrate radical, their reaction with the unsaturated lipid 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC), and the determination of the reaction products in comparison to those obtained from a reaction with only ozone in air by MALDI-FTMS is described. The results indicate the importance of nitrate radical in ozone toxicity