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EN
The study investigates the effect of heat treatment on the microstructure evolution and properties of an age-hardened Cu-3Ti-2Mg alloy. The precipitated Cu2Mg and β'-Cu4Ti phases consequently yield a depletion of the Cu matrix in regards to Ti and Mg solutes, which enhances the electrical conductivity. The Cu2Mg Laves phase and β'-Cu4Ti phase precipitates increase the hardness of the alloy due to the consistency and coherency of the later phase. However, the decrease of hardness is mainly associated with the coarse microstructures, that can be formed due to the phase transformation from metastable β'-Cu4Ti phase to more stable Cu3Ti phase. In the range of experiments, the optimum process is solution treatment at 700°C for 4 h, with subsequent age-hardening at 450°C for 4 h. The electrical conductivity, hardness, tensile strength, and elongation of the Cu-3Ti-2Mg alloy were 15.34 % IACS, 344 HV, 533 MPa, and 12%, respectively.
2
Content available Mauritius, Rodrigues (z wodą w tle)
PL
Artykuł ma charakter wspomnienia omawiające warunki, w jakich realizowano projekt FAO, którego celem była ocena zasobów wodnych i organizacja służby hydrologicznej na wyspie Rodrigues, należącej do Republiki Mauritiusu. Na podstawie danych z Mauritiusu, gdzie funkcjonuje dosyć dobrze służba hydrologiczna, oceniono w przybliżeniu zasoby wodne wyspy Rodrigues. Objętość wody opadowej jest duża, ale cyklonalny, zmienny rozkład opadów, wysokie parowanie, a przede wszystkim szybki odpływ powierzchniowy, spowodowany wylesieniem wyspy, powodują dotkliwy niedobór wody słodkiej. Gromadzenie wody poprzez budowę zbiorników retencyjnych, zalesienie i racjonalne metody agronomiczne jest możliwe tylko w sytuacji prawidłowego rozpoznania dyspozycyjnych zasobów wodnych i ich rozkładu w czasie i przestrzeni. W tym celu przewidziano organizację służby hydrologicznej na wyspie Rodrigues, kontrolującej stany wody, natężenie przepływu i zgromadzoną wodę w zbiornikach retencyjnych. Zaplanowano instalację pięciu stacji hydrologicznych: dwóch na istniejących zbiornikach retencyjnych, jednej na zbiorniku projektowanym i dwóch na potokach w warunkach naturalnych. W sąsiedztwie stacji hydrologicznych zaplanowano stacje opadowe. Wybór sprzętu hydrologicznego i warunki instalacji stacji były trudne ze względu na krótkie czasy koncentracji wezbrań, prędkości wody, które mogą przekraczać 6 m/s oraz transport grubego rumowiska rzecznego. Przewidziano limnigrafy i pluwiografy Stevens na karty magnetyczne. Zainstalowano prowizorycznie dwie stacje na zbiornikach w celu oceny zgromadzonych zasobów wodnych oraz szkolenia personelu. Dalsze prace przewidziano w kolejnych etapach projektu, ale ich losy nie są znane.
EN
This article traces work in the FAO project on Rodrigues Island belonging to the Republic of Mauritius. The objective of the project was to assess the water resources of Rodrigues Island, which suffers from freshwater scarcity, and to organize the hydrological service that does not exist on the island. On the basis of hydrological data from Mauritius, it was possible to estimate the water resources on the island. Water inflows on this island are relatively high, but the cyclonic nature of the precipitation, high evaporation, and especially the very rapid surface runoff due to deforestation, are the cause of the freshwater shortage. In order to retain water, it is necessary to know its availability and distribution in space and time. The creation of a hydrological service was therefore planned in order to control precipitation, water level, flow rates and the volume of water stored. Five stations were planned. hydrological equipped with limnigraphs and pluviographs: of which three stations on water reserves and two on natural torrents. The choice of measurement equipment was problematic for the courses of water with very short concentration time, high flow rates exceeding 6 m/s and solid flow consisting of large rocks. Stevens Materials with Magnetic Cards have been proposed. Two temporary stations on the water reservoirs were set up to monitor the volumes of water stored and to form young hyroloquia, has this method. Continuing work was scheduled by the next phase of the project.
EN
This paper simulates the responses of water budget components to doubled CO2 (2 × 378 ppm) concentration in the atmosphere with atmospheric and oceanic surface warming of 2°C. Simulations employed version 4.7 of the Regional Climate Model of the International Centre for Theoretical Physics (ICTP). Two six-year experiments were each repeated twice with the same model physics and parameterizations. The control experiment held the CO2 concentration at 378 ppm (no warming), while the other experiment specified doubled CO2 concentration and warming. The results showed a positive response (60-100% increase) to doubled CO2 for precipitation, runoff, and storage terms in Sierra Leone, Burkina Faso, Guinea Bissau, and the ocean area between 3 and 13°N. However, there was a negative response (up to 60%) for northern Senegal, southern Mali, and northern Nigeria. The reductions in water fluxes were observed mostly on the leeward side of the highlands. Evapotranspiration showed a negative response (1-20%) to doubled CO2 on the land north of 20°N. Burkina Faso and southern Mali responded oppositely to doubled CO2, despite their spatial proximity.
EN
This study focuses on precipitationdischarge data-driven models, with regression analysis between the weighted maximum rainfall and maximum discharge of flood events. It is also the first of its kind investigation for the Wernersbach catchment, which incorporates data-driven models in order to evaluate the suitability of the model in simulating the discharge from the catchment and provide good insights for future studies. The input parameters are hydrological and climate data collected from 2001 to 2009, including precipitation, rainfall-runoff and soil moisture. The statistical regression and artificial neural network models used are based on a data-driven multiple linear regression technique, and the same input parameters are applied for validation and calibration. The artificial neural network model has one hidden layer with a sigmoidal activation function and uses a linear activation function in the output layer. The artificial neural network is observed to model 0.7% and 0.5% of values, with and without extreme values respectively. With less than 1% error, the artificial neural network is observed to predict extreme events better compared to the conventional statistical regression model and is also better suited to the tasks of rainfall-runoff and flood forecasting. It is presumed that in the future this study’s conclusions would form the basis for more complex and detailed studies for the same catchment area.
PL
W artykule pokazano, że na znacznym obszarze Polski sumaryczny opad roczny zależy od liczby plam słonecznych. Wystąpienie powodzi i intensywnych opadów jest bardziej prawdopodobne w okresach małej aktywności słońca niż dużej. Fakt ten może być wykorzystany przy planowaniu budowy dróg i mostów.
EN
The article demonstrates that in a significant area in Poland the total annual precipitation depends on the number of sunspots. Floods and heavy rainfall are more likely during the periods of low rather than high sun activity. This fact can be used when planning the construction of roads and bridges.
EN
Soil erosion by water is one of the most important factors affecting contemporary landscape changes within the lowland geoecosystems in Central Europe. Soil erosion by water mainly depends on: rainfalls (especially its intensity and erosivity), length of slope and its inclination, type of cultivation and usage of land, anti-erosion treatments and susceptibility of soils to erosion. The aim of conducted research was to evaluate conditioning and magnitude of secular and extreme soil erosion processes in the Drawsko Lakeland with special considering of rainfall erosivity index (EI30). The main goal was realised through several research tasks. The first task involved examination of surface runoff and slope wash conditionings, course and quantity in the testing plot located within the Chwalimski Potok catchment. The second task was related to evaluate rainfall impact to soil erosion by water processes. It was realised by computation rainfall characteristics: intensity, kinetic energy and erosivity. In order to assess secular and extreme soil erosion impact to land relief changes, research were provided with additional details by conducting three field experiments with simulated rainfall. Stationary observation and quantitative researches of soil erosion (at testing plots) have been conducting within the Chwalimski Brook catchment for three hydrological years (2012–2014). The slope with the test area is located within the 1st order catchment being a subsystem of the Młynski Brook catchment and then followed by the upper Parsęta catchment. This area covers 4.8 hectares and is characterised by short slopes with small height variances up to 10 meters. Historically, the area was covered with agricultural crops, currently they cover about 10% of the area. The slope is covered with gleyic retisols and its average inclination is about 4 degrees with its south-east exposure. The measuring system of soil erosion covered 5 testing plots with different agricultural use (bare fallow, meadow, potatoes, spring and winter crops). Plots are 42 metres long and 4 metres width. In the bottom edge of each plot catchers with volume of 800 dm3 were installed. In this research, only data from black fallow were considered. Such tillage is recognised as a standard in soil erosion studies. Two experiments have been conducted in this testing plot. The third one has been conducted on slope located within an area of undulated morainic plateau in the Kłuda catchment. The slope is characterised by greater height variances than in Chwalimski Brook catchment. The slope, where the experiment has been conducted, is situated within local closed depression and is covered by sands underlain by boulder clay. Its average slope is about 10° with its southwest exposure. Although annual precipitation in the three-year measurement period was comparable with mean value from multi-year period (1987–2014), its intensity and erosivity were distinguishably lower. Such rainfall conditions are not favourable for extreme soil erosion by water processes, thus any relief forms from such geomorphological processes were not observed in the Drawsko Lakeland. Due to lack of that kind of forms, in 2013 and 2014, three field experiments were conducted. The main aim of experiments was to evaluate the impact of high intensity rainfall on soil surface. The first experiment consisted of 5, the second and the third of 4 rainfall simulations. The rainfall was created by using a purpose-built rain simulator, consisting of 3 and 6 sprinklers placed around the testing plot. Despite the slope inclination in the Kłuda catchment was 2.5 times steeper than Chwalimski Potok’s slope, surface runoff attained smaller volume, because of remarkably higher infiltration rate. In 2012–2014, surface runoff and soil loss has occurred 8 times each year. The maximal monthly surface runoff volume was registered in February 2012, and it equalled 10.1 dm3 m−2 and the maximal soil loss value was registered in May 2013 and equalled 3,198 kg ha−1. Annual runoff volumes were between 31.2 dm3 m−2 in 2012 and 38.8 dm3 m−2 in 2013, whereas annual soil loss values ranged from 740 kg ha−1 in 2012 to 5,700 kg ha−1 in 2013. Soil erosion values caused by simulated rainfall during field experiments were similar or significantly higher than annual values. Surface runoff was between 31.2 dm3 m−2 in the first experiment and 34.2 dm3 m−2 in the second one, whilst soil loss was between 4,632 kg ha−1 and 8,637 kg ha−1. The achieved experiment results have been compared with soil erosion rate achieved from stationary observations. The results show that runoff and soil loss considerably increase during rainfalls with high amount, intensity and erosivity. Furthermore, individual extreme erosive events may exceed annual (secular) soil erosion processes. Conducted stationary research indicates that annual soil erosion primarily depends on individual rainfall and erosive events, which considerably exceed mean values. In order to evaluate the soil susceptibility to erosion by water in the Drawsko Lakeland, high resolution potential and actual soil erosion risk maps were prepared. The qualitative assessment of soil erosion risk was based on geoinformation technologies. The model considers following conditions affecting the size of soil erosion: slope steepness and aspect, topographic factor LS (unit upslope contributing area), lithology, rainfall erosivity (Modified Fournier Index calculated from monthly and annual precipitation data) and land use and land cover from Corine Land Cover 2006. To prepare the map of potential soil erosion risk, land use from Corine Land Cover was not considered. Thematic maps have been reclassified into a 4-degree division. The results of the soil erosion risk assessment in the Drawsko Lakeland reveal the fact that a majority of its area is characterized by moderate or low erosion risk levels. Areas with high erosion risk are mostly located in the northern part of the Lakeland. The achieved results from stationary observations and field experiments may indicate that the soil loss magnitude significantly increases during rainfall with higher intensity, greater totals and accumulated in time rainfall events. This may confirm the high potential of soil erosion by water processes of above- -average magnitude and intensity in the discharge of material from agricultural used slopes.
EN
The purpose of the paper is to analyze the spatial variability of precipitation in Poland in the years 1981–2010. The average annual rainfall was 607 mm. Precipitation in Poland is characterized by high spatial and temporal variability. The lowest annual precipitation was recorded in the central part of the country, where they equaled 500 mm. The highest annual precipitation totals were determined in the south, equaling 970 mm. The average precipitation in the summer half-year is 382 mm (63% of the annual total). On the basis of data from 53 climate stations, maps were made of the spatial distribution of precipitation for the period of the year and winter and summer half-year. The kriging method was used to map rainfall distribution in Poland. In the case study, cross-validation was used to compare the prediction performances of three periods. Kriging, with exponential type of semivariogram, gave the best performance in the statistical sense. Their application is justices especially in areas where landform is very complex. In accordance with the assumptions, the mean prediction error (ME), mean standardized prediction error (MSE), and root mean-square standardized prediction error (RMSSE) values are approximately zero, and root-mean-square prediction error (RMSE) and average standard error (ASE) reach values well below 100.
EN
Lysimeters represent the ideal tool for direct measurement of soil water balance components in soil profiles. Changes in the water content in a soil monolith can be measured with sufficient accuracy by the precise lysimeter weighing system. Water content changes in soil monolith as derived from lysimeter mass represent one of the basic water balance component. This paper deals with the development and comparison of individual soil water balance components in two different soil profiles from the Easter-Slovakian-Lowland. Two lysimeter vessels were filled monolithically with two different soil profiles covered with grass: one sandy soil profile from locality Poľany and one silty-loam soil profile from locality Vysoká nad Uhom. A constant groundwater level of 1 m below ground level was maintained in both soil profiles. Under the same meteorological conditions, all differences in the development of water balance components were caused only by the differences in soil profiles. The actual evapotranspiration and water flows at the bottom of the soil profiles were compared. Sandy soils are generally considered to be more prone to drought than silty-loam soils. Under the specific conditions of this experiment (maintaining a constant groundwater level) the opposite was shown, when the silty-loam soil profile was more prone to drought than sandy soil profile. Sandy soil profile from Poľany reacted more quickly to precipitation (or evaporation). Due to the higher hydraulic conductivity of the sandy soil compared to the silty-loamy soil, the groundwater level response to external stimuli was much faster.
EN
The intensive agricultural use of the land affects both quantity and quality of river water in the catchment area. Such impact is visible also in the Szreniawa River catchment in the Małopolskie Voivodeship. The combination of intensive plowing and soil susceptibility to water erosion are the main causes of soil and nutrients depletion during the heavy rainfall. The aim of the study is to determine changes in the water quality in the Szreniawa River catchment compared to the agriculture use and precipitation level. The quality of surface water has been analysed in the river catchment area in three sampling points. The concentration of the total suspended soils in the samples collected after heavy rainfall in August 2017 reached a value of 837 mg·dm–3. The average concentrations of N-NO3 in the years of 2016–2019 ranged from 0.16 to 13.46 mg·dm–3, with the highest values in the summer (up to 13.46 mg·dm–3). The concentration of N-NH4 and P-PO4 in the Szreniawa water was affected by precipitation. The highest value of average concentration of N-NH4 3.00 mg·dm–3 was recorded in the autumn of 2019 in the middle section of the river. The highest value of P-PO4 0.90 mg·dm–3 was recorded in the autumn of 2019 mostly due to water erosion of the loess areas. Erosion has been caused by the short-term heavy rainfall. As a result, suspended solids, soluble and insoluble phosphorus compounds leaked to the river.
EN
Studies associated with climate change and variability are of great importance at both the global and local scale in the global climate crisis. In this study, change-point detection and trend analysis were carried out on mean, maximum, minimum air temperatures and total precipitation based on monthly, seasonal and annual scale in Bartın province located in the western Black Sea Region of Turkey. For this aim, 4-different homogeneity tests (von Neumann test, Pettitt test, Buishand range test and standard normal homogeneity test) for changepoint detection, Modified Mann–Kendall test and Şen’s innovative trend test for trend analysis, and Sen’s slope test for the magnitude estimation of trends were used. According to the test results, the summer temperatures in particular show increasing trends at the 0.001 significance level. Mean maximum temperature in August, mean minimum temperature in June and August, and mean temperature in July and August are in increasing trend at the 0.001 significance level. Over a 51 year period (1965–2015) in Bartın province, the highest rate of change per decade in air temperatures is in August (0.55°C for Tmax, 0.46°C for Tmin and 0.43°C for Tmean) based on Sen’s slope. However, the study showed that apart from October precipitation, there is no significant trend in monthly, seasonal and annual precipitation in Bartın. Increasing trends in mentioned climate variables are also visually very clear and strong in Şen’s innovative trend method, and they comply with the statistical results. As a result, the study revealed some evidence that temperatures will increase in the future in Bartın and its environs.
EN
Using additives with water absorbing characteristics enables us to increase the amount of water in natural basins and significantly decrease the amount of water for agricultural usage. Despite various additives already existing, they are yet to be commonly used due to high cost price, complex technology, toxic impact and instability in biological and atmospheric conditions. However, the «Natlen» composite, which is a naturally based additive, is ecologically safe. It has a long shelf life, is cheap and provides high antifiltering rates. The composite is eruptive with dispersity of any type and is jelly when boosted. In an antifiltering layer it never cracks under static and dynamic influences. It has no seam and is resistant to aggressive liquids. It is ecologically safe. «Natlen» composite is recommended for building water basins in pastures, where it can particularly be used to satisfy the demand for drinking water for cattle.
EN
The amount and distribution of precipitation plays a vital role in the management of water resources, agriculture and foodrisk preparedness. Unfortunately, Zambia like many other developing countries is a highly data-scarce country with few and unevenly distributed meteorological stations. The objective of this study was to run a comparative analysis of satellite-based rainfall products (SRPs) and gauge data to ascertain the reliability of using SRPs for daily rainfall measurements in Zambia. The four daily SRPs examined in this study include the following: The Tropical Applications of Meteorology using Satellite and ground-based observations version 3 (TAMSATv3), Precipitation Estimation from Remotely Sensed Information using Artifcial Neural Networks (PERSIANN), the Climate Hazards group InfraRed Precipitation with Station data version 2 (CHIRPSv2.0), and the African Rainfall Climatology Version 2 (ARCv2). SRPs were compared to rain gauge data from 35 meteorological, agrometeorological, and climatological stations in Zambia for the period 1998–2015. Statistical analyses were extensively carried out at temporal scales inter alia daily, monthly, seasonal and annual. Comparisons were also done for three stations lying at the highest, middle and lowest elevations to examine the ability of SRPs to capture precipitation occurrences on complex topography. Strong coefcient of determination (>0.9) of all the SRPs and gauge data were found at the monthly scale even over multifaceted topography. However, the ability of these products to capture rain gauge data at daily, seasonal and annual scales difers markedly. Specifcally, PERSIANN outperforms all the other SRPs at all scales, CHIRPSv2.0 is rated second, followed by TAMSATv3 and ARCv2, respectively. These results suggest that PERSIANN can reliably be used in studies that seek to estimate rainfall in data-sparse regions of Zambia at any temporal scale and arrive at similar results to rain gauge data.
13
Content available remote Physicochemical Properties of Copper Modified Zeolite
EN
Zeolites have been used in environmental engineering mainly in catalytic processes and as ion exchangers in water and wastewater treatment. Selective modified zeolites allow significant improvement in the effectiveness of impurities’ removal without introducing additional reagents to the environment. The final effect of treatment of water solutions is determined by the catalyst used, its physicochemical properties and the process parameters. In this work effectiveness of zeolite modification methods as well as their physical and chemical stability, taking into account the changes that take place during the process of calcination within the temperature range of 250°C to 650°C is presented. A natural clinoptilolite used in the experiment was transformed into the hydrogenous form and subsequently modified with copper (II) ions by coprecipitation with NaOH and Na2CO3. The effect of the method of the zeolite modification on Cu content, the zeolite Leaching capacity and surface charge was evaluated. An analysis of experimental results has shown that calcination temperature does not significantly change the surface charge, but does affect copper speciation. Analysis of EDS spectra by a scanning microscope, which showed that new and regular forms of copper compounds had been formed along the zeolite lattice structure is also presented. The experimental results show that retention of Cu in zeolites was caused by electrostatic interactions between Cu(II) cations and the electronegative surface of the zeolite and coprecipitation of Cu(II) complexes. Physicochemical properties of examined zeolites were affected by processes of hydration, hydrolysis and complexing of Cu with the zeolite matrix as a function of the solution’s pH. Results show that the process of impurities’ removal from water and wastewater depends on the method of zeolite modification and on the solution’s pH.
PL
W inżynierii środowiska zeolity stosowane są przede wszystkim jako wymieniacze jonowe w oczyszczaniu wody i ścieków oraz w procesach katalitycznych. Selektywne modyfikowane zeolity pozwalają na znaczące zwiększenie skuteczności usuwania zanieczyszczeń, jednocześnie nie wprowadzając dodatkowych reagentów do środowiska. O końcowym efekcie decyduje rodzaj zastosowanego katalizatora, jego właściwości fizykochemiczne oraz parametry prowadzenia procesu. W pracy przedstawiono efektywność metod modyfikacji zeolitów oraz ich stabilność fizyczną i chemiczną, z uwzględnieniem zmian zachodzących podczas procesu kalcynacji w zakresie temperatur od 250°C do 650°C. W badaniach zastosowano zeolit naturalny klinoptylolit, który przeprowadzono w formę wodorową roztworem HCl, a następnie poddawano modyfikacji jonami miedzi (II) metodą współstrącania z użyciem NaOH i Na2CO3. Oceniono wpływ sposobu prowadzenia modyfikacji zeolitu na zawartość Cu, jego rozmywalność oraz ładunek powierzchniowy. Analiza wyników badań wykazała, że temperatura kalcynacji nie wpływa istotnie na zmianę ładunku powierzchniowego, ale na formę występowania związków miedzi. W pracy przedstawiono również analizę widm EDS wykonanych mikroskopem skaningowym, która pokazała, że wzdłuż struktury krystalicznej zeolitu zostały utworzone nowe i regularne formy związków miedzi. Wyniki badań wykazały, że zatrzymywanie Cu w zeolitach zachodziło na skutek oddziaływań elektrostatycznych między kationami Cu(II) i elektroujemną powierzchnią zeolitu oraz w wyniku strącania i współstrącania kompleksów Cu(II). Czynnikami wpływającymi na właściwości fizykochemiczne badanych zeolitów są procesy hydratacji, hydrolizy i kompleksowania Cu z matrycą zeolitu w funkcji pH roztworu. Przedstawiona w pracy analiza wyników badań wykazała, że proces usuwania zanieczyszczeń z wód i ścieków uzależniony jest od sposobu modyfikacji zeolitu oraz od pH roztworu.
PL
W przemyśle naftowym istnieje wysokie ryzyko wytrącania się osadów nieorganicznych na różnych etapach wydobycia ropy naftowej ze złoża, jak również podczas zabiegów intensyfikacyjnych i transportu ropy. Aby spowolnić, opóźnić lub znaczne zminimalizować (czasem praktycznie do zera) proces wytrącania się osadów, optymalnym rozwiązaniem jest zastosowanie odpowiednich inhibitorów. Dzięki zastosowaniu metody przedstawionej w pracy weryfikuje się skuteczność działania inhibitorów osadów siarczanu baru i strontu w warunkach dynamicznych z uwzględnieniem wpływu temperatury, ciśnienia i warunków przepływu. Oprócz testu statycznego, test w warunkach dynamicznych jest podstawowym badaniem pozwalającym na ocenę inhibitorów przed ich zastosowaniem w warunkach przemysłowych.
EN
Four com. inhibitors were used to avoid pptn. of CdSO₄ and SrSO₄ after mixing of incompatible water from oil industry with seawater. The tests were carried out according to a developed method at 70°C under pressure 50 bar, at flow 2 cm³/min and for 50 min. For 2 inhibitors, a min. concn. 50-60 ppm was detd. at which easy brine flow for 50 min was possible. For 2 other inhibitors, even the increase of their dose to 1000 ppm did not protect the mixt. against pptn.
15
Content available remote Dynamika przemieszczeń wybranych osuwisk w Karpatach
EN
The paper presents the activity ofselected landslides where instrumental monitoring has been carried out within the Framework of Landslide Counteracting System (SOPO). The temporal relationships between subsurface dynamics (displacements) and geological structure with respect to atmospheric precipitation are discussed. In order to expose these relationships, the landslides were divided into two groups: the first one is located in the areas where the bedrock is made up of flysch formations with the predominance of clay rocks. The second group is located in areas with the prevalence of sandstones in the bedrock. The analysis of the 10-year record shows that, in the areas where the geological structure is dominated by clays, the landslides present continuous activity with displacements not exceeding a dozen mm/year. In the areas where in the geological foundation (bedrock) sandstones are dominated, landslide movements were usually more impulsive. Dislocations were recorded mainly after intense, long-lasting precipitation or heavy rainstorms. In extreme situations the large displacements caused total destruction of the measuring column.
PL
W pracy przedstawiono syntetyczny opis katastrofalnych powodzi, które w latach 1813-2010 wystąpiły na obszarze Krakowa. Opisu dokonano, uwzględniając ogólnie dostępne materiały. Na ich podstawie wskazano intensywne opady występujące na obszarze powyżej Krakowa jako najczęstszą przyczynę wystąpienia powodzi. Najwyższe opady atmosferyczne wystąpiły w typach cyrkulacji cyklonalnej zwłaszcza północnej (Nc), zachodniej (Wc) oraz w bruździe cyklonalnej (Bc). Najczęściej powodzie te wystąpiły w miesiącach letnich tj. w czerwcu, lipcu oraz w sierpniu, ale na przestrzeni wielu lat miały również miejsce w miesiącach pory chłodnej. Nie tylko swym zasięgiem objęły Kraków, ale były to powodzie o zasięgu regionalnym. Najwyższy stan wody rzeki Wisły w Krakowie w XIX wieku wystąpił podczas lipcowego wezbrania w 1813 roku i wyniósł 995 cm, natomiast w XX wieku najwyższy stan wody obserwowany na wodowskazie w Krakowie, który został zlikwidowany w 1965 roku, wyniósł 952 cm.
EN
The paper presents a synthetics description of the catastrophics floods that occured in 1813-2010 in the area of Cracow. The discription was made based on generally available information. Based on that, intensive rainfalls occurring in the areas above Cracow, has been identified as the most common cause of he floods in Cracow. The highest precipitation occurred in cyklonal circulation types, especially northern (Nc), western (Wc) and through of low pressure (Bc). Most often these floods occurred in the summer months, i.e. in June, July and in August. However, over the years occurred in the months of cool season as well. Floods occurred not only in the city of Cracow, but in the region as well. The highest water level of the Vistula River in Cracow in the 19th century was observed during July surge in 1813 and reached 995 cm, while in the 20th century the highest water level of 952 cm was observed on the water gauge in Cracow. This water gauge was removed in 1965.
EN
In the recovery process of rare earth (RE) from the weathered crust elution-deposited rare earth ore, ammonium sulfate is used as the leaching liquor to leach RE, and then the leachate containing RE3+ can be precipitated by oxalic acid and the RE oxalate precipitation mother liquor is reused for RE leaching process after removing the residual oxalic acid by precipitation with calcium hydroxide. However, the reuse process of precipitation mother liquor cannot proceed in the strong acid and alkali restricted areas and the discharge of mother liquor which contains a large amount of ammonium salt will cause ammonia-nitrogen waste and pollution. In order to realize the reuse of the precipitation mother liquor in this area, the direct reuse of RE oxalate precipitation mother liquor for RE leaching was investigated in this study. The RE oxalate precipitation process and the RE leaching process with oxalic acid were studied. The results showed that the residual oxalic acid concentration in the mother liquor can be controlled lower than 0.8 g/dm3 at pH 2-3 when the RE concentration in the leachate was 0.1- 1.5 g/dm3 and the RE precipitation rate reached to 94%. In addition, RE leaching efficiency was up to 90% while the oxalic acid concentration in the prepared mother liquor was 0.2-0.8 g/dm3, pH 2-3. Therefore, the precipitation mother liquor with oxalic acid concentration less than 0.8 g/dm3 could be directly reused for RE leaching. However, considering the different performance of RE ores, the recommended oxalic acid concentration in the direct used precipitation mother liquor was lower than 0.6 g/dm3.
EN
In this study beneficiation of Ga from alunite ore was investigated. The effects of the calcination temperature, H2SO4 concentration, leaching temperature and liquid-solid ratio on the dissolution characteristic of Ga, K and Al were studied. The results showed that increasing the calcination temperature, H2SO4 concentration and leaching temperature can improve the solubility of K and Al. However, higher H2SO4 concentration and lower leaching temperature can improve the dissolution of Ga, which was beneficial to recovery of Ga. On the basis of the solubility difference in H2SO4, a two-stage process of selective acid leaching and alkali precipitation of Ga was proposed. The concentration of Ga was increased significantly from 54 g/t in alunite ore to 4100 g/t in alkali precipitation product. The major elements of Al and K in alunite were recovered as the alum crystal with a purity of 99.62%.
EN
In the present study, time series for annual, monthly rainfall and number of rainy days per year were analysed to quantify spatial variability and temporal trends for 22 rainfall stations distributed in northeastern Algeria for the period 1978– 2010. The Mann–Kendall test and the Sen’s slope estimator were applied to assess the significance and magnitude of the trend. The results showed that precipitation decreases spatially from North to South and from East to West. The application of the Mann–Kendall test (for 0.05% threshold) to the time series data showed that for annual precipitation, no station showed statistically significant trends, unlike the number of rainy days, where there was a significant negative trend in four stations (Jijel, Constantine, Oum El Bouaghi and Tébessa). For the monthly time series, significant positive trends were observed during the months of September in the coastal stations and July for the plateaus and southern Saharan Atlas stations, while significant negative trends were recorded during the months of February and March for the stations of the extreme East in the study area. These results revealed that for the period analysed, there was no significant climate change in northeastern Algeria but there is a seasonal delay having important agroecological implications.
PL
W przedstawionych badaniach analizowano serie rocznych i miesięcznych opadów oraz liczbę dni z deszczem w ciągu roku celem ustalenia przestrzennej zmienności i czasowych trendów w latach 1978–2010 dla 22 stacji pomiarowych rozmieszczonych w północnowschodniej Algierii. Wykorzystano test Manna–Kendalla i estymator Sena do oceny istotności i rozmiaru trendu. Wyniki dowodzą, że opady malały z północy na południe i ze wschodu na zachód. Zastosowanie testu Manna–Kendalla (p < 0,05) do serii danych pomiarowych nie wykazały w żadnej stacji statystycznie istotnych trendów dla rocznych opadów w przeciwieństwie do liczby dni z opadem, które cechował istotny negatywny trend w czterech stacjach pomiarowych (Jijel, Constantine, Oum El Bouaghi i Tébessa). Analiza serii miesięcznych opadów dowiodła występowania dodatniego trendu w odniesieniu do sierpnia w stacjach na wybrzeżu i w odniesieniu do lipca w stacjach na płaskowyżach i w południowym Atlasie Saharyjskim. Istotny trend ujemny uzyskano w przypadku lutego i marca w stacjach na wschodzie badanego obszaru. Wyniki dowodzą, że w analizowanym okresie nie stwierdzono istotnych zmian klimatu w północnowschodniej Algierii, z wyjątkiem sezonowych opóźnień, które wywołują ważne skutki agro-ekologiczne.
EN
This investigation was undertaken to determine the optimum conditions for physical-chemical treatment of waste water contaminated with heavy metals in the industry of metallic coatings. The industry uses substances such as: inorganic acids, alkalis, acidic and alkaline metal salts, that has a high water demand in the processes of flushing and cleaning the parts to be coated. According to the preliminary characterization of samples and reported in the literature theory, physico-chemical process was implemented for the removal of contaminants that consisted in chemical oxidation of CN-ions, followed by chemical precipitation made next to a coagulation/flocculation and subsequent adsorption on activated coal. Laboratory scale tests showed the optimal conditions of treatment including chemical oxidation by the addition of 4.15 cm3 of H2O2 (30%) per gram of CN, chemical precipitation with NaOH to a pH of 12, followed by coagulation/flocculation with Fe2(SO4)3 at a speed of 135 rpm for 3 min and 20 rpm for 20 min and finally the addition of 1.0 g of adsorbent previously activated at 700°C. From this study, it is clear that the adsorption on activated carbon is highly efficient in the removal of heavy metals from industrial waste water from electroplating. However, it is also clear that the parallel application of the treatments, shown here, is more effective to completely remove contaminants such as lead, nickel, silver, and copper at laboratory scale, so it is recommended the simultaneous use of these physico-chemical processes.
PL
Badania podjęto celem ustalenia optymalnych warunków fizycznego i chemicznego oczyszczania ścieków z galwanizerni. Zakłady takie wykorzystują kwasy nieorganiczne, alkalia i sole metali o odczynie kwasowym bądź zasadowym. Ponadto zużywają one dużo wody w procesie oczyszczania i płukania pokrywanych metalami elementów. Na podstawie wstępnej charakterystyki próbek i danych literaturowych wdrożono fizyczny i chemiczny proces usuwania zanieczyszczeń, który polegał na chemicznym utlenianiu jonów CN oraz chemicznym wytrącaniu, koagulacji/flokulacji oraz adsorpcji na węglu aktywnym. Testy w skali laboratoryjnej wykazały, że optymalne warunki oczyszczania obejmowały chemiczne utlenianie dzięki dodatkowi 4,15 cm3 H2O2 (30%) na gram CN, chemiczne strącanie NaOH do pH 12, a następnie koagulację/ flokulację z prędkością 135 obr.∙min–1 przez 3 min i 20 obr.∙min–1 przez 20 min oraz dodatek 1,0 g adsorbentu aktywowanego wstępnie w 700°C. Badania wykazały, że adsorpcja na węglu aktywnym jest wysoce efektywna w usuwaniu metali ciężkich ze ścieków galwanizerskich. Równoległe stosowanie zabiegów przedstawionych w pracy zapewnia jeszcze większą efektywność w całkowitym usuwaniu ołowiu, niklu, srebra i miedzi w skali laboratoryjnej. Dlatego równoczesne stosowanie tych zabiegów jest zalecane w praktyce.
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