排序方式： 共有25条查询结果，搜索用时 773 毫秒
1.
Rajmund DYBCZYNASKI Halina POLKOWSKA-MOTRENKO Zbigniew SAMCZYNASKI Zygmunt SZOPA 《Geostandards and Geoanalytical Research》1991,15(2):163-185
World-wide intercomparison runs has made possible the certification of two new Polish geological-environmental reference materials for multi-element trace analysis: Apatite Concentrate (CTA-AC-1) and Fine Fly Ash (CTA-FFA-1). "Recommended values' are established for 25 (CTA-AC-1) and 40 (CTA-FFA-1) elements respectively. In addition, "information values' are assigned for 12 elements in CTA-AC-1 and 10 elements in CTA-FFA-1. Our method of data evaluation has been further improved and a modified version of criteria for assigning recommended and information values is proposed. 相似文献
2.
3.
Marcin Słowik Tadeusz Sobczyński Zygmunt Młynarczyk 《Environmental Earth Sciences》2010,59(5):957-966
Research concerning chemical constitution of alluvial sediments was done in the lower course of the Obra river (Western Poland).
The fragment of vertical profile, which consisted of various alluvial sediments (fine sands, peats, and sandy silts) was chosen
for detailed analysis. The main research problem was to determine if lithology and chemical constitution of alluvial deposits
are interconnected in a distinct way within studied section of the Obra river valley, and, if changes of chemical elements’
concentration could be used to illustrate depositional processes, which take place in riverbed and floodplain. Concentrations
of Fe, Mn, Cu, Zn, Ca, Mg, and K were determined in collected sediment samples. Next, geochemical groups of alluvial sediments
were distinguished using cluster analysis. Investigated changes of chemical elements’ concentration show that there is a distinct
border between the environment of organic sediments, which marks the place of former functioning of the Obra riverbed, and
sandy silts, which were deposited within floodplain during floods. Besides, floodplain sediments, riverbed sediments, and
reductive environment within peat deposits were singled out on the basis of the analysis. 相似文献
4.
Agnieszka Generowicz Zygmunt Kowalski Joanna Kulczycka Agnieszka Makara 《洁净——土壤、空气、水》2011,39(7):688-696
The proposal of application of multi‐criteria analysis and technological quality method for optimization of technological processes on the case study of sodium chromate production variants from waste was presented. The research on the use of chromic waste for the production of sodium chromate made it possible to determine the optimal process parameters. Technological quality method was used to define the value of criterions for multi‐criteria analysis while multi‐criteria analysis allowed determining the impact of criterions weights for ranking variants of technological process. Both methods in a complex way evaluate the degree of modernization of technologies, describing them qualitatively within the area of environmental, technical, and the economic effects of the proposed technological variants. Based on the proposed evaluating criteria both methods yield comparable results. The most advantageous alternatives provided realization of the sodium chromate production process with the use of in‐process recycling of chromic mud, off‐site recycling of chromic tannery waste and on‐site recycling of waste from the old chromic heaps. 相似文献
5.
A numerical study which takes into account wave dispersion effects has been carried out in the Indian Ocean to reproduce the initial stage of wave propagation of the tsunami event that occurred on December 26, 2004. Three different numerical models have been used: the nonlinear shallow water (nondispersive), the nonlinear Boussinesq, and the full Navier-Stokes aided by the volume of fluid method to track the free surface. Numerical model results are compared against each other. General features of the wave propagation agreed very well in all numerical studies. However some important differences are observed in the wave patterns, i.e., the development in time of the wave front is shown to be strongly connected to the dispersion effects. Discussions and conclusions are made about the spatial and temporal distribution of the free surface reaffirming that the dispersion mechanism is important for tsunami hazard mitigation. 相似文献
6.
7.
Flood and vortex scour were observed in the Prosna channel (Central Poland) in the years 1980–1985. Flood scour increases the thickness of the reworked channel deposits by 30 per cent to 66 per cent, in relation to the thickness determined by the elevation of the normal bed and the bankfull stage. Vortex scour can increase the thickness by as much as 90–95 per cent. Knowledge of these properties of contemporary alluvium allows correct palaeohydrological and stratigraphic interpretation of the alluvial fills of valley floors. 相似文献
8.
9.
Zygmunt Meyer 《Acta Geophysica》2011,59(2):317-333
The wind set-up of water level in a river is of great importance in many practical cases, notably in the river mouth section
where the slope of the free water table is very small (sometimes 10−5) and the wind shear stress acting at the water surface generates significant changes in the vertical velocity profile. If
the wind is blowing opposite to the main flow, an increase of water depth is observed. In the outlet area, the increase of
water depth can reach up to 0.5 m (Lower Odra River). The paper presents an analysis of wind set-up of water level based on
hydrodynamic principles. 相似文献
10.
Organochlorine pesticides in fish from the southern Baltic Sea: levels, bioaccumulation features and temporal trends during the 1995-2006 period 总被引：1，自引：0，他引：1
The levels of HCH isomers, HCB and summation DDTs were determined in five species of Baltic fish collected during 1995-2006. Some downward time trends of HCH isomer, pp'-DDE and pp'-DDD concentrations in Baltic fish were observed; in contrast, HCB and DDT concentrations did not exhibit any obvious trend. Concentrations of summation HCHs expressed on a lipid weight basis were very similar in all species studied. In contrast, concentrations of summation DDTs varied in tested species. The most abundant HCH isomer was beta-HCH and among DDT-related compounds, pp'-DDE prevailed. In our investigations the sampling sites were not a crucial factor for organochlorine pesticide concentrations and patterns observed in fish, but the occurrence of several inter-species differences in the bioaccumulation features of OC pesticides were observed. For cod there was a positive correlation between fish size (length) and summation DDT concentration. In herring, sprat and salmon samples, summation DDT concentrations were negatively correlated with fat content. 相似文献