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EN
Ordovician was an extremely turbulent period for the Earth system, where the Great Ordovician Biodiversification Event (GOBE) occurred in the early-middle Ordovician. Many hypotheses were proposed, taking into account both biotic and abiotic factors. One such hypothesis posits that global cooling led to a transition from greenhouse to icehouse climate systems, which further triggered feedback mechanisms such as increased oceanic circulation, bio-productivity, and oxygenation during the middle Ordovician. Direct evidence, however, is still scarce. Here, we have compiled a comprehensive dataset of δ18O (10,636) from carbonate rocks and fossil shells as well as clumped isotope temperature data (Δ47; 88) spanning the entire Ordovician. Our study investigates climate change from both temporal and spatial perspectives. We assessed the effects of the late diagenesis alteration, lithological differences, different depositional environments and water depths on the carbonate δ18O, and corrected the latitudinal effect of the δ18O in seawater. The latitudinal temperature gradient (LTG) was introduced to account for the spatial patterns of climate change, which here refers to the difference in sea-surface temperature between low (<20°) and low-to-middle (20–40°) latitudes. We observed a gradual increase in the LTG from Tremadocian to Dapingian, indicating an amplified thermal contrast between low and low-middle latitudes. It suggested a remarkable climate cooling and shift towards an icehouse climate state, coinciding with the GOBE. From Darriwilian to Sandbian, the LTG weakens significantly and the temperature difference decreases, which is consistent with the plateau of global temperatures and the slow change in species diversity. After Sandbian, a progressive steepening of LTG was observed, which provides the first evidence for low paradoxical atmospheric CO2 at the Late Ordovician. Our study supports the global cooling hypothesis and sheds light on the links between climate change and biological evolution across the Ordovician.
EN
The Guelma-Bouchegouf irrigated perimeter uses water from the Bouhamdane dam between May and the end of October. It should be noted that the water is channelled to the perimeter via Seybouse Wadi, which serves as a water collector. The water is supplied during the dry season, which causes water pollution due to strong evaporation and industrial discharges. Moreover, during the summer period irrigation increases since the crops grown are industrial tomatoes, melon, watermelon and beans, requiring intense and sustained watering. The measurement of the conductivity of the water flow shows a clear increase from 3000 μs/cm to 6000 μs/cm. This increase is connected to interactions between water and rock, compounded by the adverse impact of climate change. It should be noted that during this period the average temperature is 26°C and sometimes temperature values exceeding 40°C are recorded. In addition, industrial discharges into the Seybouse Wadi occur without pre-treatment, leading to water pollution by heavy metals. The results of the analyzes of the Seybouse Wadi waters show the presence of pollutants such as iron, manganese, zinc, copper and nutrients in the upstream zone (Guelma region). In the downstream area (Annaba) we notice the presence of pollutants such as chromium, lithium, iron, manganese and nutrients.
PL
Celem pracy było opracowanie i zwalidowanie metody oznaczania zawartości itru w eluatach uzyskiwanych z kolumn zawierających żywicę DGA, w celu sprawdzenia jej właściwości pod kątem powinowactwa do itru i stopnia jego zatrzymywania. Wykorzystana została technika optycznej spektrometrii emisyjnej ze wzbudzeniem w plazmie indukcyjnie sprzężonej (ICP-OES).
EN
The oldest Jurassic (Kimmeridgian) Plattenkalk occurs in Wattendorf on the northern Franconian Alb (southern Germany). It is a 15 m thick alternation of laminated dolomite and limestone, interbedded with carbonate debris layers in a depression ~2 km across and a few tens of metres deeper than the surrounding microbial-sponge reefs. The Plattenkalk overlies a few tens of metres of microbialsponge biostrome facies and bedded, micritic basinal limestone. The bulk-rock stable isotopes of the micritic basinal facies gradually change from normal marine (δ13C ~ +2‰, δ18O ~ –2‰ VPDB) to lower values (δ13C ~ 0‰, δ18O ~ –6‰) in a ~ 40 m thick interval including Plattenkalk and suggest ageing of the bottom waters. The surrounding reefs are isotopically nearly invariant (δ13C ~ +2‰, δ18O ~ –2‰ VPDB). An isotope anomaly (δ13C of > ~ –9‰) is restricted to the basinal facies and is most pronounced in the biostrome facies. This indicates methanogenesis, which is documented in negative δ13C in dedolomite, calcite-cemented dolomite and calcite concretions and occurred probably mainly below seabed. The Konservat-Lagerstätte was probably deposited near an oxygen minimum zone in a water column with low productivity of organic material. Dolomite is in isotopic equilibrium with Plattenkalk and was probably deposited as protodolomite from chemically modified, aged seawater. 87Sr/86Sr ratios of bulk carbonate are often slightly radiogenic, probably due to random analytical sample contamination by clay minerals. Belemnite and some matrix 87Sr/86Sr is slightly lower than that of Kimmeridgian seawater, either caused by basin restriction or by fluids derived from the diagenesis of Oxfordian rocks below. An equivalent Upper Kimmeridgian depression ~23 km distant and a somewhat younger Konservat-Lagerstätte in Poland show a δ13C isotope anomaly below the main fossil beds. Isotopic evidence for saline bottom waters, the current interpretation, is lacking. This study also shows that micritic carbonates can preserve their early diagenetic, marine δ18O signal, which is correlatable over tens of kilometres
6
Content available remote Isotopic composition of precipitation in Poland: a 44-year record
EN
Isotopic composition of precipitation (2H/1H and 18O/16O isotope ratios, tritium content) is nowadays widely used in numerous applications of environmental isotopes—most notably in hydrology, climatology and biogeochemistry. Here we present a long record (44 years) of stable isotope composition and tritium content in monthly precipitation available for the Krakow station (southern Poland). Krakow is the only site in Poland for which long-term record of the isotopic composition of monthly precipitation is available. The tritium data are discussed here in the context of generally declining levels of bomb tritium in the global atmosphere and growing influence of technogenic emissions of this isotope. Two aspects of temporal variability of stable isotope composition of precipitation collected in Krakow are discussed here: (i) seasonality and (ii) interannual changes of δ18O and δ2H signal. Whereas the seasonality of stable isotope signal is generated mainly by seasonally varying the degree of rainout of air masses bringing moisture from the source regions (subtropical Atlantic Ocean) to the centre of the European continent, the North Atlantic Oscillation seems to govern interannual changes of δ18O and δ2H on the decadal timescale. Progressing warming of the local atmosphere, in the order of 1.8 °C in the past four decades, leaves its imprint in stable isotope signal measured in Krakow precipitation; the slope of isotope–temperature relationship is in the order of 0.50‰/°C for δ18O and 3.5‰/°C for δ2H.
EN
Morphostructural, hydrogeological and hydrochemical approaches were applied to Hammamet plain and its surrounding mountains in the eastern part of Algeria to characterize the groundwater system and its potential for exploitation. The Essen and Troubia Mountains form the natural boundaries of Hammamet plain. The objective of this study is to utilize remote sensing techniques combined with structural analysis, hydrogeology and hydrogeochemistry to identify the potential fracture zones for groundwater in the strongly fractured and karstified deep aquifers. The delineated zones of potential groundwater resources are verified by detailed hydrogeological field surveys. From a hydrogeological point of view, these two mountains, constitute a unit limited by faults oriented ENE-WSW, NNW-SSE and NNE-SSW. Specifically, fractures of the latter two directions influence the compartmentalization and the hydrogeological functioning of this unit. According to the degree of fracturing and/or karstification, two basic types of aquiferous behaviour have been distinguished: fissured aquifer (Essen Mountain and Troubia Mountain), and porous aquifer (Hammamet plain). The study of the hydrochemical characteristics of groundwater samples shows that the majority of samples are mainly of HCO3– and Ca2+ water type. The ionic speciation and mineral dissolution/precipitation was calculated with the PHREEQC software. The chemical composition of the water is influenced by the dissolution and/or precipitation processes during the water–rock interaction and by the cationic exchange reactions between groundwater and alluvial sediments. The high content of CO2 in the water samples suggests that they circulate in a geochemical open system. The isotopic analysis of some groundwater samples shows a similarity with the meteoric waters, which reflect their short residence time and a low evaporation of the infiltrated water.
PL
Celem scharakteryzowania systemu wód podziemnych oraz możliwości eksploatacji tych wód zastosowano metody morfologiczne, hydrogeologiczne i hydrochemiczne na równinie Hammamet i otaczających ją górach we wschodniej części Algierii. Góry Essen i Troubia tworzą naturalną granicę równiny Hammamet. Przedmiotem badań była identyfikacja możliwych stref szczelin w silnie spękanym i głębokim, krasowym poziomie wodonośnym z zastosowaniem technik teledetekcji w połączeniu z analizą strukturalną, hydrogeologią i hydrogeochemią. Wytyczone strefy potencjalnych zasobów wód gruntowych weryfikowano w szczegółowych hydrogeologicznych badaniach terenowych. Z hydrogeologicznego punktu widzenia wymienione góry stanowią jednostkę ograniczoną przez uskoki ułożone wzdłuż linii ENE-WSW, NNW-SSE i NNE-SSW. Szczeliny w dwóch ostatnich kierunkach wpływają na podział i hydrologię tej jednostki. Według stopnia spękania i/lub postępu procesów krasowych wyróżniono dwa główne typy poziomów wodonośnych: poziom spękany (góra Essen i góra Troubia) oraz poziom porowaty (równina Hammamet). Badanie hydrochemicznych właściwości próbek wody gruntowej wykazało, że są one zdominowane przez HCO3– i Ca+2. Skład jonowy i procesy rozpuszczania/wytrącania obliczano za pomocą programu PHREEQC. Na skład chemiczny wody wpływają procesy rozpuszczania i precypitacji w czasie oddziaływań między wodą a podłożem skalnym oraz wymiana kationów między wodą gruntową a aluwialnymi osadami. Duże stężenie CO2 w próbkach wody sugeruje, że krąży ona w systemie otwartym. Analiza izotopowa niektórych próbek wody wykazuje ich podobieństwo do wód opadowych, co uwidacznia się w ich krótkim czasie retencji i niewielkim parowaniu wód infiltracyjnych.
8
Content available remote Characterization of some selected mud volcanoes of southern Taiwan
EN
In the present study, some mud volcanoes in Pingtung and Kaohsiung areas were selected. The selected mud volcanoes are located above the mud diaper system in southern Taiwan. Three different sampling techniques were used to collect samples in and around the said mud volcanoes. The results show that river water samples from different places fall on the meteoric line. Mud samples are found to be heavier in oxygen isotope while hydrogen isotope remains the same. Soil gas samples were also collected at the depth of 1 m and dissolved gases from the mud volcanic site (or nearby) were collected for gas chromatography analyses. Soil gas samples and dissolved gas from mud pool and groundwater were analyzed for radon concentration using RAD7 (solid-state nuclear track detector) bi-weekly. Long-term investigation will be needed to understand the relationship of mud volcanoes the eruption cycle with gas composition variations. It will also help to understand their relationship with tectonic activities in the region.
EN
The paper contains the results of analysis of chemical, isotopic and trace metal composition of anomalous spring water in the Tatra Mts. Obtained data were the basis for an attempt to determine the origin of this hydrogeochemical anomaly. The spring is located in the Tomanowa Valley in the Western Tatra Mts. The spring water is characterized by the mineralization (TDS) above 500 mg/dm3. As regards the chemical composition of the water, Ca2+ ions show the highest concentration among cations, while HCO- among anions. The spring water has been assigned to the: SO —HCO—Ca-Mg hydrochemical type. Among trace metals, Sr, Ba, B, Li and Al. reveal The highest concentrations. The oxygen and hydrogen isotopic composition(δ18O and δ2H) indicates that this is infiltration water. Delta values of oxygen and sulphur isotopes (δ18OS and δ34S) of the sulphate ion indicate that SO4 of this spring water is likely derived from leaching of gypsum or anhydrite evaporites.
10
Content available remote Wymagania prawne przy organizacji i funkcjonowaniu oddziału radioizotopowego
PL
Zgodnie z przepisami dotyczącymi ochrony radiologicznej, prowadzenie leczenia izotopowego dawkami jodu promieniotwórczego powyżej 800 MBq wymaga hospitalizacji w warunkach oddziału radioizotopowego. Uruchomienie takiego oddziału wiąże się ze spełnieniem szeregu wymogów dotyczących pomieszczeń, wyposażenia w urządzenia diagnostyczne i mierniki promieniowania, zapisanych w rozporządzeniach wykonawczych do ustawy Prawo atomowe. Aby uruchomić taki oddział, należy uzyskać zezwolenie Prezesa Państwowej Agencji Atomistyki na prowadzenie działalności związanej z narażeniem na promieniowanie jonizujące oraz zgodę na udzielanie świadczeń medycznych Głównego Inspektora Sanitarnego.
EN
According to regulations on radiation protection, the management of treatment of radioactive iodine isotope doses above 800 MBq requires hospitalization in the conditions of radioisotope branch. Launching such a branch demands meeting a series of requirements such as premises supplied with diagnostic equipment as well as radiation meters, which is recorded in the executive regulation to the state of Atomic Agency. To run such a branch, and carrying out activities involving exposure to ionizing radiation must by authorized by the President of the National Atomic Energy Agency as well as the consent to the provision of medical services by the Chief Sanitary Inspector must be given.
PL
Organizacja Zakładu Medycyny Nuklearnej, a dokładniej wymogi techniczno-budowlane dotyczące zarówno pracowni izotopowych, jak i pracowni rentgenowskich, opisano w ustawie Prawo atomowe i rozporządzeniach towarzyszących. Przed przystąpieniem do prac nad realizacją Zakładu Medycyny Nuklearnej należy dokładnie przemyśle, jakie badania mają by w nim realizowane, a zatem jakie radioizotopy i ich aktywności będą do tego potrzebne. Po ustaleniu zakresu działalności należy dokona wyboru klasy pracowni – wymagania techniczne, budowlane i wyposażenie ściśle się z tym wiążą. W publikacji opisano wymagania dla pracowni izotopowej klasy II.
EN
Organization of the Department of Nuclear Medicine, more precisely – the requirements technical construction on the isotope laboratory and X-ray laboratories are described by the Act on Atomic Law and accompanying regulations. Before taking an action aimed at creating the Department of Nuclear Medicine it is necessary to assess what types of tests we are going to do, and thus what radioisotopes and their activities will be needed. Then, it is needed to determine the class of the studio – the technical requirements, and construction equipment are closely associated with it. The requirements for isotope laboratory class II, are described in the publication.
PL
Z badań składu chemicznego i izotopowego wód górnojurajskiego poziomu wodonośnego rejonu Buska-Zdroju i Solca- Zdroju wynika, że są to solanki pierwotne i wody słone, zasilane w okresie przedplejstoceńskim, kiedy klimat charakteryzował się długimi okresami znacznie cieplejszymi niż współcześnie. Solanki te mają zdecydowanie cięższy skład izotopowy niż wody lecznicze, siarczkowe występujące na tym obszarze w utworach kredowych (głównie cenomanu) oraz zbliżone wartości wskaźników hydrochemicznych do wód morskich.
EN
The study of the chemical and isotopic composition of the Upper Jurassic aquifer in the Busko-Zdrój and Solec-Zdrój region suggests primary nature of the brines supplied before the Pleistocene under climate conditions characterized by long and much warmer periods than today. Compared to the sulphide healing waters occurring in the Cretaceous formations, mainly of Cenomanian age, the discussed brines and salt water are characterized by a far heavier isotopic composition as well as by the values of hydrochemical indica¬tors mostly similar to those of marine waters.
EN
The Qolqoleh gold deposit is located in the northwestern part of the Sanandaj–Sirjan Zone (SSZ), within the NE–SW trending Qolqoleh shear zone. Oligocene granitoids, Cretaceous meta-limestones, schists and metavolcanics are the main lithological units. Chondrite-normalised REE patterns of the ore-hosting metavolcanics indicate REE enrichment relative to hanging wall (chlorite-sericite schist) and footwall (meta-limestone) rocks. The pattern also reflects an enrichment in LREE relative to HREE. It seems that the LREE enrichment is related to the circulation of SO42- and CO2-bearing fluids and regional metamorphism in the Qolqoleh shear zone. Both positive and negative Eu anomalies are observed in shear-zone metavolcanics. These anomalies are related to the degree of plagioclase alteration during gold mineralisation and hydrothermal alteration. In progressing from a metavolcanic protomylonite to an ultramylonite, significant changes occurred in the major/trace element and REE concentration. Utilising an Al-Fe-Ti isocon for the ore-hosting metavolcanics shows that Sc, Y, K, U, P, and M-HREE (except Eu) are relatively unchanged; S, As, Ag, Au, Ca, LOI, Rb and LREE are enriched, and Sr, Ba, Eu, Cr, Co and Ni decrease with an increasing degree of deformation. Based on geochemical features and comparison with other well-known shear zones in the world, the study area is best classified as an Isovolume-Gain (IVG) type shear zone and orogenic type gold mineralisation. Based on the number of phases observed at room temperature and their microthermometric behaviour, three fluid inclusion types have been recognised in quartz-sulphide and quartz-calcite veins: Type I monophase aqueous inclusions, Type II two-phase liquid-vapour (L-V) inclusions which are subdivided into two groups based on the homogenisation temperature (Th): a) L-V inclusions with Th from 205 to 255°C and melting temperature of last ice (Tm) from –3 to –9°C. b) L-V inclusions with higher Th from 335 to 385°C and Tm from –11 to –16°C. Type III three-phase carbonic-liquid inclusions (liquid water-liquid CO2-vapour CO2) with Th of 345–385°C. The mean values of the density of ore-forming fluids, pressure and depth of mineralisation have been calculated to be 0.79–0.96 gr/cm3, 2 kbar and 7 km, respectively. The δ18Owater and δD values of the gold-bearing quartz-sulphide veins vary from 7.2‰ to 8‰ and –40.24‰ to –35.28‰, respectively, which are indicative of an isotopically heavy crustal fluid and likely little involvement of meteoric fluid. The δ18Owater values of the quartz-calcite veins have a range of –5.31‰ to –3.35‰, and the δD values of –95.65‰ to –75.31‰, which are clearly lower than those of early-stage quartz-sulphide-gold veins, and are close to the meteoric water line. Based on comparisons of the D–O isotopic systematics, the Qolqoleh ore-mineralising fluids originated from metamorphic devolatilisation of Cretaceous volcano-sedimentary piles. Devolatilisation of these units occurred either synchronously with, or postdates, the development of penetrative (ductile) structures such as shear zones and during overprinting brittle deformation.
EN
C-isotopes, TOC and O geochemical data from the lower Aptian Cuchía section in the western Basque-Cantabrian basin (BCB) allow an accurate delimitation of the OAE1a-equivalent and its geochemical Menegatti´s segments, a detailed δ13Ccarb correlation with regional and interregional sections, and a high-resolution construction of TOC and bulk-rock δ18Ocarb curves and their interpretation. The δ13Ccarb values range from -2‰ and +4‰ (VPDB). They agree with previous data from the eastern BCB sections (Aralar) confirming the ammonite age of the OAE1a in the Basque-Cantabrian basin: Deshayesites forbesi, Deshayesites deshayesi, and Deshayesites deshayesi-Dufrenoyia furcata transition Zones. Interregional δ13Ccarb correlation with pelagic (Cismon, Italy, and Mid-Pacific Mountains, DSDP Site 463) and neritic (Roquefort-La Bédoule, France) core sections, reveals a common profile of a wide negative excursion characteristic of the OAE1a. It consists of a double trough separated by a flat relative maximum, with two negative spikes in the upper trough of neritic sections. TOC absolute values range from 0.12% to 1.37%. Segments of the TOC curve with persistent low values closely correspond with descending segments of the δ13Ccarb curve, and are attributed to lesser organic productivity in the BCB. Detailed bulk-rock δ18Ocarb data (-5.71‰ to -1.05 ‰ PDB) and variation curve show two main positive O-isotope shifts and three minor positive inflections, within a general negative trend characteristic of the OAE1a. The two major positive shifts correspond to both shallowing upwards sequences and the lowermost can be related to a eustatic sea level fall. Independent interregional correlation of the O-isotope shifts with C-isotopes supports their interpretation as punctuating colder events within a general warming trend.
PL
Celem artykułu jest przedstawienie aktualnego stanu wiedzy na temat oznaczeń trwałych izotopów ołowiu oraz możliwości wykorzystania wyników badań w różnych dziedzinach nauki. Skład izotopowy ołowiu oznaczany w różnych próbkach (np. środowiskowych, medycznych, artefaktach archeologicznych) może służyć wyjaśnieniu problemów naukowych z zakresu ochrony środowiska, geologii, kryminalistyki, archeologii, ekologii, nauki o żywieniu i in. Popularność badań trwałych izotopów ołowiu wynika, między innymi, z coraz lepszego dostępu do nowoczesnych technik analitycznych pozwalających na precyzyjny pomiar stężeń izotopów (TIMS, MC-ICP-MS, LA-ICP-MS i in.). W niniejszym artykule skrótowo omówiono metodykę oznaczania trwałych izotopów ołowiu oraz podano przykłady badań stosunków izotopowych ołowiu w różnych dyscyplinach naukowych.
EN
The aim of this paper is to present the current knowledge on determination of stable lead isotopes and to discuss the possibility of their application in different scientific disciplines. Lead isotope ratio determined in different kinds of samples (e.g. environmental samples, medical samples, artifacts) may be useful for elucidation of scientific problems in environmental sciences, geology, criminology, arheology, ecology, nutrition sciences etc. Growing popularity of lead isotope ratio studies results from facilitate access to modern analytical techniques that enable precise isotope measurements (TIMS, MC-ICP-MS, LA-ICP-MS etc.). This article briefly discusses the methods used in stable lead isotope determinations and gives examples of the studies carried out by researchers specializing in different scientific disciplines.
PL
Termin izotop pochodzi z języka greckiego (izos-topos) i oznacza "to samo miejsce". Odnosi się to do miejsca, "tego samego", które zajmuje dany pierwiastek w układzie okresowym. Izotopy to odmiany pierwiastka chemicznego różniące się liczbą neutronów w jądrze atomu. Izotopy możemy podzielić na dwie podstawowe grupy : izotopy stabilne i nietrwałe (radioaktywne).
EN
The hypothesis of Jarvis et al. (2006) that a [delta^13]C (calcite) reference curve based upon bulk samples from the Upper Cretaceous Chalk of England can be used as a primary criterion for trans-continental correlation is reviewed in the light of new stable isotope data from the Upper Albian and Cenomanian chalks of eastern England and from the Cenomanian to Campanian chalks of southern England. Evidence demonstrates that in the coloured chalks of eastern England the cements invariably have positive [delta^13]C values (up to 3.5[per mil]) except where they have been affected by hardground development when the cements have negative [delta^13]C values down to -6.5[per mil]. in contrast, the White Chalk of southern England may have cements with [delta^13]C values as negative as -8[per mil]. Modelling indicates that the coloured chalks may preserve a truer record of the primary palaeo-oceanographic [delta^13]C signal than the white and grey chalks of southern England. it is suggested that (1) many of the 72 isotope events described from the [delta^13]C (calcite) reference curve and proposed for correlation may reflect the effects of variations in the type and extent of calcite cementation; and (2) until much more is known about the patterns of calcite cementation in the Upper Cretaceous Chalk the use of minor isotope events for trans-continental stratigraphic correlation can only be applied with the utmost caution.
PL
Zbadano piaskowce pochodzące z 15 otworów wiertniczych. Reprezentują one głównie arenity oraz waki kwarcowe i sublityczne. Osady te składają się przede wszystkim z ziaren kwarcu mono-i polikrystalicznego, litoklastów, skaleni i łyszczyków. Lokalnie obserwuje się wzrost udziału glaukonitu i Fe-ooidów. Piaskowce uległy procesom diagenetycznym, głównie kompakcji, cementacji i rozpuszczaniu. Rozpoznano efekty kompakcji mechanicznej. W wyniku cementacji powstały głównie minerały węglanowe, ilaste, żelaziste i fosforanowe. Cementy węglanowe występują obficiej od innych. Kalcyty zawierają zmienne domieszki Fe. Minerały syderytu mają skład syderoplesytu. Ponadto rozpoznano związki żelaza: getyt, hematyt oraz piryt. Wśród autigenicznych minerałów ilastych stwierdzono glaukonit, berthieryn i kaolinit. Nodule fosforytowe obecne w osadach górnego albu są zbudowane z frankolitu. Większość minerałów powstała podczas eodiagenezy. Mniej liczne skutki cementacji nastąpiły w etapie mezodiagenezy, gdy osady zostały głębiej pogrzebane. Piaskowce uległy procesom telodiagenezy podczas tektonicznej inwersji obszaru badań. Procesy kompakcji i cementacji spowodowały ograniczenie przestrzeni międziarnowej. Podczas rozpuszczania ziaren kwarcu i skaleni utworzone zostały wtórne pory.
EN
The investigations were carried out on sandstones from 15 boreholes. The rocks are represented chiefly by quartz and sublithic arenites and wackes, and composed mostly of mono-and polycrystalline quartz grains, lithoclasts, feldspars and micas. Fe-ooids and glauconite are locally observed. The sandstones have undergone diagenetic processes, mainly of compaction, cementation and dissolution. Effects of mechanical compaction were identified. As a result of cementation processes, carbonate, clay, iron and phosphatic minerals were formed. Among these carbonate cements occur abundantly. Calcites contain admixture of Fe. Siderites show a composition of sideroplesite. Authigenic clay minerals are represented by glauconite, berthierine and kaolinite. There are also iron compounds: goethite, hematite and pyrite. The Upper Albian deposits contain phosphatic nodules composed of francolite. Most of the minerals formed during eodiagenesis. Less frequent effects of cementation occurred during mesodiagenesis when the deposits were buried to larger depths. The sandstones were subjected to processes of telodiagenesis during tectonic inversion of the study area. Compaction and cementation processes resulted in reduction of intergranular space. During dissolution of quartz and feldspar grains, secondary pores were formed.
20
Content available remote Redukcja listków bocznych w układach antenowych częściowo nieregularnych
PL
W opracowaniu przedstawiono koncepcję jednowymiarowych układów antenowych z częściową nieregularnością geometryczną. Pokazano, że efektywna redukcja listków bocznych w charakterystyce promieniowania układu antenowego jest możliwa przy częściowej nierównomierności rozmieszenia elementów. Do określenia rozmieszczenia zastosowano optymalizacyjny aIgorytm roju cząstek i środowisko Matlab. Analizowano układy antenowe opisane uproszczonym modelem matematycznym złożone ze źródeł izotropowych. Wykonano symulacje komputerowe I przedstawiono wyniki.
EN
Conception of one-dimensional array antennas with partial geometric irregularity is presented in this paper. It is shown, that there is possibility of effective sidelobe level reduction in radiation pattern of array antenna by partial irregularity of radiators spacing. We use particle swarm optimization algorithm and Matlab to determine spacing of radiators. Only simple mathematic model of array of isotropic sources was analyzed. Computer simulations were made the results are presented.
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