This article analyzes the composition and distribution of chemical elements in friction films and their effect on the tribological properties of the self-lubricating, high-temperature antifriction composite based on EP975 powder nickel alloy with CaF2 solid lubricant. Analysis of the chemical elements by energy-dispersive spectroscopy (EDS) showed their uniform distribution, on both the composite’s surface and the counterface’s surface. The alloying elements’ uniform distribution leads to a uniform distribution of the corresponding phases and structural elements in the antifriction film. This ensures high tribological properties at high temperatures. Analysis of the material’s tribological properties, by means of metallographic and micro-X-ray research confirmed the correctness of the technology for producing the composite. Solid lubricant CaF2, alloying elements, and their corresponding phases form the continuous antiscoring film. The film influences the antifriction properties formation during the friction process and provides a self-lubricating mode under the action of high temperature and oxygen. Antiscoring, self-lubricating CaF2 films minimize wear of the friction pairs and defend the contact surfaces against intensive wear. The dense antifriction films have smooth microtopography, which stabilizes the high-temperature friction unit operation. Thus, the self-lubrication mode is realized for a long exploitation time. Tribological properties analysis allowed us to determine the ranges of rational exploitation modes for the material being studied: a load up to 5.0 MPa, a slide speed from 0.3 to 1.0 m/s, a temperature up to 800°C, in the air. The results obtained opened the opportunity to control the antifriction film formation and the composite’s tribological properties by the choice of the initial ingredients while taking into account the operating conditions.
Chemical components in groundwater from mine drainage or used in geothermal installations are a potential source of valuable minerals. At the Polish Geological Institute - National Research Institute, a study was carried out to identify the content of elements in mine waters, wells exploiting natural gas and oil as well as geothermal and therapeutic waters in Poland. The aim of the research was to recognize the concentration of potentially useful minerals in groundwater and the possibility of their recovery. It was the first project that focused on the recovery of elements from groundwater on a national scale in Poland. For this purpose, 67 sites were selected, in which 75 water samples were taken and the content of65 chemical components was determined. Then, the amount of minerals that could be recovered from mine waters and geothermal brines was calculated based on the amount of water pumped in each facility. The calculations involved the approximate efficiency and working time of the recovery installation. As a result of this research, it was found that the mine waters and geothermal brines in Poland contain resources of valuable elements in very different amounts. In more than half of the examined sites, the estimated resources of minerals are present in amounts that are not prospective. However, in 29 sites, mine waters and geothermal brines contain elevated concentrations of several elements, including - B, Br, I, K, Li, Mg and Mn. If they were successfully recovered, they could represent a potential additional income for the mining and geothermal industries. Dębieńsko Desalination Plant of mine waters in Upper Silesia is the most promising potential source of recovery of minerals from mine waters, where the total resources of minerals to be recovered from concentrated brine have been estimated as the highest. Rudna Copper Mine in Lower Silesia is in second place, with one of the highest resources and the largest amount of minerals to be recovered from groundwater. Other sites are: the SOLINO Salt Mine, “Olza” mine water collector, mine waters pumped from abandoned coal mines in the Upper Silesia (in Zabrze, Siemianowice Śląskie, Czeladź, Gliwice), and plants producing geothermal energy in Stargard, Pyrzyce and Bańska. Total amount of mineral resources that can be recovered from waters pumped from the most promising sites is over72 000 tonnes annually. Taking into account both the ecological aspect and the potential economic benefits of recovering minerals from mine waters and geothermal brines, it is necessary to continue the studies on the recovery of minerals from highly mineralized waters in Poland.
Waste management is a very important issue for the sustainable development of the modern world. The metallurgical industry is an industry that has been generating and still generates large amounts of waste that may have a negative impact on the natural environment and human health. Metallurgical waste comes from current production and is collected in landfills/heaps. Any research enabling the management of waste, including metallurgical waste, is justified. This study presents the results of research on waste that can be used in the production of aggregates – research related to natural radioactivity and the introduction of hazardous substances into water or soil. The study highlights the diversified chemical composition of metallurgical waste, which requires detailed research of the waste before it is directed to the production of aggregates. Aggregate, as a building material, is subject to specific legal (normative) regulations. Metallurgical waste that meets the requirements for the protection of the natural environment and human health should be used for the production of building materials - it is an environmentally friendly activity that implements the principles of sustainable development.
4
Dostęp do pełnego tekstu na zewnętrznej witrynie WWW
Rok 2017 jest czasem wielu rocznic związanych z Marią Skłodowską-Curie i jej dokonaniami. 150 rocznica urodzin uczonej, 120 rocznica urodzin Ireny Joliot-Curie, 10 rocznica śmierci Ewy Curie Labouisse i 85 rocznica otwarcia Instytutu Radowego w Warszawie to przyczynek do wielu wydarzeń i artykułów na temat życia, odkryć i osiągnięć Marii Skłodowskiej-Curie. Historia badań nad promieniotwórczością, pierwiastkami promieniotwórczymi, to historia fizyki jądrowej, chemii radiacyjnej i onkologii. Oczywiście Maria i Piotr Curie nie byli jedynymi uczonymi zajmującymi się tymi dziedzinami, ale niewątpliwie to właśnie oni, a właściwie Maria Skłodowska-Curie była inicjatorką tak nowoczesnego myślenia o atomie. To dzięki jej uporowi, odwadze w stawianiu pytań i wydawałoby się niemożliwych do udowodnienia hipotez, nauka zawdzięcza nowe metody badawcze i pierwiastki promieniotwórcze. To jej kompleksowe myślenie o badaniach naukowych i medycynie dało początek nowoczesnym metodom leczenia nowotworów, powstanie dwóch bliźniaczych placówek onkologicznych- Instytutów Radowych w Paryżu i w Warszawie otworzyło drogę do budowy całej sieci onkologicznej i kompleksowego leczenia pacjentów.
EN
Year 2017 is a year of many anniversaries connected with Maria Skłodowska-Curie and her achievements. The 150th anniversary of the birth of Maria Skłodowska-Curie, the 120th anniversary of the birth of Irena Joliot-Curie’s, the 10th anniversary of Eve Curie Labouisse’s death and the 85th anniversary of the opening of the Radium Institute in Warsaw represent a contribution to many events and articles on Maria Skłodowska-Curie’s life, discoveries and accomplishments. The history of research on radioactivity and radioactive elements is the history of nuclear physics, radiation chemistry and oncology. Obviously, Maria and Piotr Curie were not the only scientists involved in these fields, but undoubtedly they, or Maria Skłodowska-Curie actually, who initiated such modern thinking about the atom. It is thanks to her persistence and courage to ask questions, as well as her perseverance in proving hypotheses that had been almost impossible to prove, the science owes new research methods and radioactive elements. It is Maria Curie’s comprehensive thinking about the research and medicine that has given rise to modern methods of cancer treatment, the establishment of two twin oncology centres: the Radium Institute in Paris and in Warsaw. These have opened the way to building the entire oncology network and comprehensive patient treatment.
Wysokie ceny surowców ustanowione przez Chiny są jednym z powodów, że wydobycie pierwiastków ziem rzadkich z dna oceanu będzie bardziej atrakcyjne i opłacalne dla przedsiębiorców.
Postępujący wzrost produkcji i coraz większy zakres zastosowania pierwiastków ziem rzadkich w medycynie i różnych gałęziach przemysłu stwarza realne zagrożenie zanieczyszczenia środowiska przez pierwiastki z grupy REE.
10
Dostęp do pełnego tekstu na zewnętrznej witrynie WWW
Research concerning ehanges of chosen ehemieal elements concentration in alluvial sediments was conducted in the lower course of the Obra river valley. The analyses of Fe, Mn, Cu, Zn, Ca, Mg and K concentration were done in a fragment of vertical profile, which was characterized by variable lithology. On the basis of statistical analysis (cluster analysis) an attempt was made to distinguish geochemical groups of alluvial sediments of the Obra river valley. Six geochemical groups, which represent reductive conditions within peat deposits, the environment of Hood sediments (inserts of fine sands within peats and sandy silts in the top of the profile) and the environment of river bed sediments (fine sands in the bottom part of the profile), were singled out. Results of the study show that it is possible to distinguish the above mentioned depositional environments on the basis of variations of sediments' chemical constitution.
PL
W dolnym odcinku rzeki Obry przeprowadzono badania nad zmianami koncentracji pierwiastków chemicznych w osadach aluwialnych. Analizy zawartości żelaza, manganu, miedzi, cynku, wapnia, magnezu i potasu przeprowadzono we fragmencie profilu pionowego cechującego się zróżnicowaną budową litologiczną. Na podstawie analiz statystycznych (analiza skupień) podjęto próbę wydzielenia grup geochemicznych osadów aluwialnego wypełnienia dna doliny Obry. Wydzielono sześć grup geochemicznych osadów reprezentujących środowisko redukcyjne w obrębie osadów torfowych, środowisko pozakorytowe (warstwy piasków drobnoziarnistych w torfach oraz mulki piaszczyste w stropie profilu) oraz środowisko korytowe (piaski drobnoziarniste w spągu profilu). Z przeprowadzonych badań wynika, że rozróżnienie wyżej wymienionych środowisk sedymentacyjnych jest możliwa również na podstawie zmian składu chemicznego osadów aluwialnych.
11
Dostęp do pełnego tekstu na zewnętrznej witrynie WWW
Research concerning chemical constitution of alluvial sediments was done in the lower course ofthe 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. Main research problem was to determine if lithology and chemical constitution of alluvial deposits arc interconnected in a distinct way within studied section ofthe Obra river valley, and if changes of chemical elements concentration could be used to illustrate depositional processes which take place in river bed and floodplain. Concentrations of Fe, Mn, Cu, Zn, Ca, Mg and K were determined in collected sediment samples. Investigated changes of chemical elements concentration show that there is a distinct border between the organic sediments, which mark the place of former functioning ofthe Obra river bed, and sandy silts, which were deposited within floodplain during Hoods. Besides, dependence between lithologic variability of alluvial sediments and their chemical constitution was observed. However, this dependence is not clear in some cases. The authors concluded that it is necessary to use statistic analyses to define connection between lithology and chemical constitution of alluvial deposits (distinguishing geochemical groups of alluvial sediments).
PL
Badania składu chemicznego osadów rzecznych przeprowadzono w dolnym odcinku rzeki Obry 3,5 km na północny zachód od Międzyrzecza. Do analizy wybrano fragment profilu pionowego o zróżnicowanej litologii. Głównym celem badań było określenie, czy litologia i zmienność składu chemicznego osadów rzecznych są od siebie w istotny sposób uzależnione w badanym fragmencie doliny, i na ile wiarygodny zapis zmian zachodzących na obszarze zlewni rzecznej stanowi skład chemiczny osadów aluwialnych. W pobranych próbkach osadów określono koncentrację żelaza, manganu, miedzi, cynku, wapnia, magnezu i potasu. Wykazano, że zmiany koncentracji pierwiastków chemicznych wskazują na wyraźną granicę pomiędzy środowiskiem osadów organicznych wypełniających miejsce dawnego funkcjonowania koryta, a środowiskiem pozakorytowym reprezentowanym przez osady mułkowe. Ponadto w badanym fragmencie profilu zauważalny jest związek między zmiennością litologiczną osadów aluwialnych dna doliny Obry a ich składem chemicznym. Zależność ta nie jest jednak ścisła. Wskazano na konieczność wykorzystania analiz statystycznych w celu bardziej szczegółowego określenia związku między litologią i składem chemicznym osadów rzecznych (wydzielenie grup geochemicznych osadów).
12
Dostęp do pełnego tekstu na zewnętrznej witrynie WWW
During investigations of the Baltic Sea basin significant differences have become manifest in the distribution of certain chemical elements in different chains of the geo (-eco) system (soils, river, lagoon and marine sediments). This paper presents data on the quantitative relationships of elements resulting from interactions of natural sedimentation processes and the possible human impact on the sediments from two port areas. The total (T), lithogenic (LG; stable) and hydrogenic (HG; mobile, reactive) migration forms of Zn, Cr, Cd, Cu, Pb and Ni were analysed. The HG component comprises that pool of the elements contained in readily degrading minerals increases in this form potentially being an indicator of adverse human impacts. The distribution of total forms depends on the quantity of the sediment fraction with grain size < 0.063 mm (fr. < 0.063 mm) and on the concentration of organic content (Corg). With increasing sediment depth, the concentration of elements decreases sharply, although HG concentrations were seen to increase on several occasions. One explanation for such findings is the mineralisation and decomposition of metals from the remnants of biological activities of organisms (pellets, globules) into the sediments. Element concentrations in the natural sedimentation zone (NSZ) of the marine-influenced North Port at Gdańsk are less than in the NSZ and technogenic sedimentation zone (TSZ) of the riverine part of the port of Gdańsk. The ratios between HG, LG and T in the two sedimentation zones are different for different elements, but are always higher in the TSZ than in the NSZ. Multi-site analyses of the port basins allowed NSZ and TSZ to be distinguished. The TSZ is typified by anomalous concentrations of elements, the specific distribution of their migration forms, the semi-stagnant conditions prevailing there and the proximity of human impact sources. The data presented in this paper indicate that the concentrations of only some of the elements in the TSZ sediments of the ports of Klaipeda and Gdańsk exceed the permitted norms for spoil dredged from port basins. By no means can the total load of elements contained in the spoil dumped at sea be treated as an indicator of marine pollution. For an objective assessment of the real pollution threat to port environments, detailed investigations of the various migration forms of chemical elements need to be carried out, and previously established levels revised.
13
Dostęp do pełnego tekstu na zewnętrznej witrynie WWW
Glin i chlorek sodu uszkadzają system korzeniowy i ograniczają pobieranie składników pokarmowych przez rośliny. W pracy określono zawartość następujących pierwiastków: Zn, Mn, Na, Mg, Ca i P w liściach i korzeniach odmiany żyta Motto po traktowaniu glinem w trzech stężeniach (200, 400 i 1000 žM) oraz oznaczono zawartość K, Na, Mg i Cl w siewkach wybranych zbóż (pszenica, pszenżyto, żyto i jęczmień) po działaniu chlorkiem sodu w stężeniach 170 i 300 žM. Glin, w stężeniu 200 žM, powodował obniżenie zawartości wszystkich pierwiastków w liściach i korzeniach siewek żyta odmiany Motto. Natomiast w badanych zbożach (żyto, pszenica, pszenżyto i jęczmień) po traktowaniu NaCl wystąpiła prawidłowość: obniżenie zawartości K i Mg i wzrost Na i Cl.
EN
The content of selected chemical elements in varieties of rye grown in conditions of salinity stress. The plants intake chemical elements in the shape of soluble ions in a soil solution, however if these elements occur in a different form, even in high amounts, they are for their unassimilable. An additional problem is the fact that the roots of plants have not formed the mechanisms of selective intake of biogenic elements from the substrate. For this reason, the plant cells are penetrated by elements which ensure their growth and development and also those which are unnecessary or even harmful. Additionally, the aim of this work was to determine the content of the following biogenic elements (Mg, Ca, K, P, Na, and Cl) in the shoots and roots in 14 day seedlings of 6 varieties of winter rye (Kier, Motto, Walet, Luco, Klawo and Nawid) treated with NaCl at concentrations of 0, 100, 150 and 200 žM. The varieties of rye differed slightly in content of particular elements. The stress salinity caused a reduction of content of the following elements: P, Ca, Mg and K and an increase of Na and Cl in varieties of rye. However, the Luco variety which was the most tolerant to salinity, contained somewhat more calcium, potassium, phosphorus, magnesium, chlorine and sodium.
The migration forms of basic (Ca, Mg, Na, K) and polyvalent (Fe, Mn) chemical elements, heavy metals (Cd, Cu, Ni, Pb, Zn), and water saturation with minerals under natural and polluted conditions in shallow groundwater of Lithuania were calculated using a computer program WATEQ4F. Change of metals migration forms with increase of their concentration and alkalinity of environment has been well described by logarithmic functions, which can also be used for the forecasting. The migration forms of chemical compounds enable to identify the pollution sources and intensity of their influence.
PL
Wykorzystując program komputerowy WATEQ4F, określono możliwe formy migracji pierwiastków chemicznych o stałej wartościowości (Ca, Mg, Na i K) i o różnych wartościowościach (Fe, Mn) oraz metali ciężkich (Cd, Cu, Ni, Pb i Zn) w czystych i zanieczyszczonych płytkich wodach podziemnych Litwy. Zmiany mobilnych form metali wraz ze wzrostem ich koncentracji i zasadowości środowiska dobrze opisują funkcje logarytmiczne, wykorzystywane również do prognoz pogody. Mobilne formy związków chemicznych umożliwiają identyfikację źródeł zanieczyszczenia oraz intensywność ich wpływu na środowisko.
Selen - pierwiastek o liczbie atomowej 34, obecnie znajdujący liczne zastosowania i służący pomocą ludziom w różnych dziedzinach życia - jest znany od początku XIX wieku. Historia tego pierwiastka zaczyna się w Szwecji.
Plants, animals, and man need for their development and proper functioning many chemical elements without which they could not live. There is a close relationship between the soil on which food is produced and health of plants, animals, and people. If the soiI is devoid of certain chemical elements then indirectly living organisms are also devoid of these elements. The following are, among other things, the causes of plant contamination with heavy metaIs: high natural content of metals in soil, emissions from industrial establishments, vehicle exhaust gases, fertilizers with high metal content, industrial waste and sewage deposits used as fertilizers. As a result of plant food consumption a human organism receives from 60 to 70% of total intake of heavy metaIs such as cadmium and lead. The results of investigations carried out for many years point to vegetables as the main source of heavy metals. From 35 to 55% of lead and from 48 to 71 % of cadmium introduced to the organism with food originate from vegetables. In Poland the increase in heavy metals content in soil corresponds with the increase in air pollution. The highest lead, cadmium, or zinc contents were found in the soils of the southern and southwestern Poland, and the lowest in the northern and northeastern parts of the country. The highest proportion of contaminated soils are present in Katowice province. The impact of industry on soil environment in form of acid rains is of long-term character. The increase in soil acidity has indirectly a negative effect on posibilities of the optimum nutrition of plants, especially with nitrogen, phosphorus, potassium, magnesium, and calcium. The change in soil acidity considerably hinders the satisfaction of nutritive demands of plants and turns on the green light for heavy metaIs. This is very dangerous for soils, plants, and animals as well as for a human being.
PL
Rośliny, zwierzęta i człowiek do swego rozwoju i prawidłowego funkcjonowania potrzebują bardzo wielu pierwiastków, bez których nie mogłyby żyć. Pomiędzy glebą, na której produkuje się żywność, a zdrowiem roślin, zwierząt i człowieka istnieje ścisła zależność. Jeśli gleba będzie pozbawiona określonych pierwiastków, pośrednio będą ich pozbawione organizmy żywe. Do przyczyn zanieczyszczenia roślin metalami ciężkimi należą m.in.: duża naturalna zawartość metali w glebie, emisja z zakładów przemysłowych i transportu, nawozy o dużej zawartości metali, odpady poprzemysłowe oraz osady ściekowe stosowane do nawożenia. W wyniku konsumpcji żywności pochodzenia roślinnego do organizmu ludzkiego dostaje się od 60 do 70% całkowitego pobrania metali ciężkich, takich jak kadm czy ołów. Wyniki prowadzonych od lat badań wskazują na warzywa jako na główne źródło metali ciężkich. Wraz z warzywami do organizmu wprowadza się od 35 do 55% ołowiu oraz od 48 do 71% kadmu dostarczanych drogą pokarmową. Na terenie Polski wzrost zawartości metali ciężkich w glebach pokrywa się z nasileniem emisji zanieczyszczeń do atmosfery. Największą zawartość ołowiu, kadmu oraz cynku stwierdzono w glebach południowej i południowo-zachodniej Polski, zaś najmniejszą w części północnej i północno-wschodniej. Najwięcej skażonych gleb znajduje się w województwie katowickim. Działalność przemysłu na środowisko glebowe w formie kwaśnych deszczów ma charakter wieloletni. Zwiększenie kwasowości gleby pośrednio wpływa negatywnie na możliwości optymalnego odżywiania roślin, a zwłaszcza azotem, fosforem, potasem, magnezem i wapniem. Zmiana kwasowości gleby znacznie utrudnia zaspokojenie potrzeb pokarmowych roślin i stwarza zielone światło dla pierwiastków metali ciężkich. Jest to bardzo niebezpieczne zarówno dla gleb, roślin, zwierząt dla człowieka.
Cosmology is presented as a branch of science dealing with the Universe. The most important achievement in this field is the Big Bang theory accounting for the formation of the Universe by an explosion 10-25 billion years ego. This event was followed by different processes schematically divided into 'Planc', 'handron', 'lepton', 'radiation|' and 'galaxy' era (Tab. 1). Universal abundance of elements is presented as a relation between logarithm of the elements (or isobars) abundance in the solar system and the atomic (or mass) numbers (Figs 1 and 2). These relations are treated as records of the Universe evolution. Four groups of the nucleosynthesis are presented according to this idea (Tab.2):(1) primary reactions at the beginning of the Universe; (2) 'burning' of light elements inside stars; (3) neutron capture inside stars; (4) photonuclear reactions inside strongly heated-up stars, natural disintegration of heavy elements inside and outside the stars, breaking of heavy elements in the interstellar space. Light chemical elements - from hydrogen to lithium - were created during the first minutes after the Big Bang by primary nucleosynthesis processes (reactions 1-7). This mechanism is responsible for very high abundance of hydrogen (~90% of all atoms in the Universe) and helium (~9%). Heavy elements are produced up to now inside stars. Special attention is paid to description of different stages and ways of star evolution (Fig. 3) and to relations of this processes to the nucleosynthesis inside stars (reactions 8-38). These processes strongly depend on the beginning mass of the star. Stars similar to the Sun are responsible for formation of carbon and oxygen only. In the bigger ones the elements up to the iron group can be formed. In the case of the largest ones supernova phenomenon is possible: the star that has exhausted its nuclear fuel, collapses into a superdense state, and explodes with a final burst of enormous energy. This is responsible for reactions from the group (4).
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.