Results 1 - 10 of 366
Results 1 - 10 of 366. Search took: 0.025 seconds
|Sort by: date | relevance|
[en] By means of some measuring values, mean hourly values of ozone and sulfur dioxide concentrations in the form of exponential-type probability density distributions are presented. This has essential advantages as compared to the usual form of indicating environmental data. Obtained is a mathematical ''formula'' describing a course in the entire range of the measured values and which can be integrated, for instance, within computer programs modelling propagation and conversion processes (especially also for sensitivity analyses). Any given percentile values can be calculated by approximation, or the probability of the incidence of extreme values of particualr biological relevance (concentration or dose) is estimated. Extreme values are also calculated by means of extremum statistics according to GUMBEL. The paper demonstrates the achievable degree of adaptation and possible applications in biology and ecology. (orig./UWA)
[de]Anhand einiger Messwerte werden Stundenmittel von Ozon- und Schwefeldioxid-Konzentrationen in Form von Wahrscheinlichkeitsdichteverteilungen vom Exponentialtyp dargestellt. Diese weist gegenueber vielfach ueblichen Angaben von Umweltdaten wesentliche Vorteile auf. Es entsteht eine mathematische ''Formel'' die den Verlauf im gesamten Bereich der gemessenen Werte beschreibt, und die z.B. in Rechenprogramme zur Modellierung von Ausbreitungs- und Umwandlungsvorgaengen eingebaut werden kann (insbesondere auch fuer Sensitivitaetsanalysen). Beliebige Percentilwerte koennen naeherungsweise berechnet oder die Wahrscheinlichkeit des Auftretens von biologisch besonders relevanten Extremwerten (Konzentration oder Dosis) geschaetzt werden. Extremwerte werden auch per Extremalstatistik nach GUMBEL berechnet. Erreichbare Anpassung und moegliche biologisch-oekologische Nutzungen werden vorgestellt. (orig./UWA)
[en] Fixed asset investment (FAI) and foreign indirect investment (FDI) have important influences on economic development and environmental quality. Because environmental performance is related with economic development, FAI and FDI may affect environment indirectly through their impacts on economic growth. In this study, the direct and indirect effects of both FAI and FDI on China's environmental quality are distinguished and separately estimated for the first time with a carefully designed framework of a two-equation model. Because most economic activities and environmental pollutions occur in the urban areas, a panel data of 112 Chinese cities for the period 2002–2015 is utilized. Several spatial factors are also introduced to control for the potential spatial correlations in economic development and pollutant emissions. The estimation results indicate that there exist apparent differences in the environmental effects of FAI and FDI. The direct effects of FAI on SO2 emissions are significant positive and dominate the negative indirect effects. By contrast, the direct, indirect and total effects of FDI on pollutant emissions are all negative. Therefore, overall speaking, well designed and targeted policies should be formulated to reduce the negative environmental impacts of FAI and to increase the positive influences of FDI on environment. - Highlights: • Influences of domestic and foreign investment on environmental quality in China are investigated. • City-level panel data of fixed asset investment (FAI) and foreign direct investment (FDI) are used. • Spatial correlations in economic development and pollutant emissions are controlled for. • The positive direct effects of FAI on SO2 emissions dominate the negative indirect effects. • The direct, indirect and total effects of FDI on both pollutant emissions are all negative.
[en] Experimental results of total electron attachment cross sections are presented with, for comparison, two additional sets of data, those of Orient and Srivastava and of Spyrou et al.. Both were normalized to present values of the first attachment peak at 4,6 eV, in order to show more clearly differences in cross section curve shapes. In fact, data of Orient and Srivastava are larger that the present ones for a factor of 2,82; while those of Spyrou et al. are higher only for 3,70 %. Both these sets of data, as well as those by Cadez et al., cover an incident electron energy range 3,40 - 9,40 eV. Electron attachment processes at energies higher that 9,40 eV have been in fact detected and measured in the same set of experiments that led to former publication of lower energy attachment processes by Cadez et al.. At that time in none of experiments, that could distinguished ionic species formed in dissociation attachment processes, was a sign of ions at incident electron energies exceeding 9,40 eV. That caused our ignorance toward processes detected and measured at higher incident electron energies, mainly since they were at least one order of magnitude lower that the two peaks at 4,6 eV and 7,3 eV, respectively. Without additional experiments, that include mass analysis of ionic species formed in dissociative electron attachment processes, it is not possible to give any sound explanation to causes of peaks at energies higher that 8,0 eV
[en] In this article there is a brief overview of some of the Soviet Union's environmental problems. Democratization, decentralization and privatization have stimulated the use of environmental impact assessments and of measures to prevent industrial accidents. A long-term nature conservation and natural resources management programme for the USSR has been developed for the period 1991-2005. (author). 1 tab
[en] This paper strikes the balance of sulfur dioxide emissions according to the refining processes used in petroleum refining plants in 1989. Statistical data about sulfur content of petroleum products and forecasts about sulfur dioxide emissions in year 2000 are also given. 3 figs., 9 tabs
[en] We discuss a series of simulations of anthropogenic sulfur over East Asia with a SO2/SO42- chemistry-transport model driven in on-line mode by a regional climate model. Sensitivity to OH and H2O2 concentration, cloud parameters, SO2 dry deposition and emission strength is analyzed and the different components of the sulfur budget are examined. The SO2 and SO42- column burden show pronounced variability at temporal scales from seasonal to synoptic and sub-daily, with SO2 and SO42- behaving differently due to the interplay of chemical conversion, removal and transport processes. Both SO2 and SO42- show marked spatial variability, with emission being the dominant term in regulating the SO2 spatial distribution. The atmospheric SO2 and SO42- amounts show close to a linear response to surface emission. Aqueous phase SO2 → SO42- conversion and wet removal are the primary factors that regulate the SO42- amounts, with dry deposition and gas phase SO2 → SO42- conversion being of secondary importance. Aqueous phase conversion and dry deposition are the dominant loss mechanisms for SO2. The model shows low sensitivity to variations in OH, H2O2, and cloud parameters, while the sensitivity to prescribed dry deposition velocity is more pronounced. Overall, our results are in line with previous modeling studies and with very limited available observations
[en] The hot 2ν2 + ν3 – ν2 hybrid band of the S18O16O molecule is assigned in the range 1800–1900 cm–1 for the first time. The spectrum is analyzed based on the method of combination differences. 56 energy levels (Jmax = 15, ) are determined based on the experimental data obtained. Rotational parameters of the (021) vibrational state are determined.
[en] Sulphur dioxide in the atmosphere at Nairobi industrial area and its environs was measured using pararosaniline method. Higher concentrations were recorded in the morning hours (14.2-112.0μgm3) than in the afternoon (14.2-112μgm3). The industrial area had higher monthly average concentrations (57.2-143.2μgm3)than residential sites (18.2-64.3μ3 ). The months characterised by unfavourable dispersion conditions (June-September) showed higher concentrations (15.5-175.5μgm3) than those months with favourable dispersion conditions (October-November): (14.2-157.8μgm3). (author)
[en] Sulfur chemistry has been implemented into the regional weather forecast model HIRLAM in order to simulate sulfur fields during specific weather situations. The model calculates concentrations of sulfur dioxide in air (SO2(a)), sulfate in air (SO4(a)), sulfate in cloud water (SO4(aq)) and hydrogen peroxide (H2O2). Modeled concentrations of SO2(a), SO4(a) and SO4(aq) in rain water are compared with observations for two weather situations, one winter case with an extensive stratiform cloud cover and one summer case with mostly convective clouds. A comparison of the weather forecast parameters precipitation, relative humidity, geopotential and temperature with observations is also performed. The results show that the model generally overpredicts the SO2(a) concentration and underpredicts the SO4(a) concentration. The agreement between modeled and observed SO4(aq) in rain water is poor. Calculated turnover times are approximately 1 day for SO2(a) and 2-2.5 days for SO4(a). For SO2(a) this is in accordance with earlier simulated global turnover times, but for SO4(a) it is substantially lower. Several sensitivity simulations show that the fractional mean bias and root mean square error decreases, mainly for SO4(a) and SO4(aq), if an additional oxidant for converting SO2(a) to SO4(a) is included in the model. All weather forecast parameters, except precipitation, agree better with observations than the sulfur variables do. Wet scavenging is responsible for about half of the deposited sulfur and in addition, a major part of the sulfate production occurs through in-cloud oxidation. Hence, the distribution of clouds and precipitation must be better simulated by the weather forecast model in order to improve the agreement between observed and simulated sulfur concentrations