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1
Content available Pomiary gęstości
PL
Przedmiotem artykułu jest charakteryzacja metod oraz przyrządów pomiarowych przeznaczonych do pomiarów gęstości i wielkości z nią związanych, stosowanych w Okręgowym Urzędzie Miar w Warszawie. Przedstawiono poszczególne metody oraz stanowiska pomiarowe, wykorzystywane do wzorcowania przyrządów i urządzeń przeznaczonych do pomiarów gęstości.
EN
The subject of the article is the characterization of methods and measuring instruments intended for measuring density and the related quantities at the Regional Office of Measures in Warsaw. The individual methods and measurement installations used to calibrate instruments and devices for measurements are presented.
EN
Excessive growth of filamentous bacteria, inducing activated sludge bulking, presents a serious problem in many wastewater treatment plants (WWTPs). The idea of using Lecane inermis rotifers as a tool for controlling the filamentous bacteria density in activated sludge requires developing a method of culturing rotifers at high concentrations. The objective of this work was to determine the effect of two culture media on the growth of three Lecane inermis strains. The growth of rotifers from a single individual (parthenogenetic female) fed the tested culture media was observed for 10 days. The rotifers showed different individual growth, depending on the strain and type of culture medium. The results of the studies suggest that by using the tested culture media, it may be possible to select a Lecane inermis strain with the highest culturing capacity at high density of rotifers in order to inoculate activated sludge with these organisms in wastewater treatment plants.
EN
This sedimentological study of the Wielkopolska Member of the Miocene Poznań Formation in the Jóźwin IIB opencast lignite-mining field, central Poland, reveals a late mid-Miocene anastomosing fluvial system with ribbon-shaped channels filled mainly by sandy and muddy deposits. The fluvial system, extending across the eastern flank of the post-Mesozoic Kleczew Graben, was tributive in its eastern upper reaches, but was increasingly distributive and northwards deflected in its lower reaches near the graben axis. Lithofacies analysis of a representative palaeochannel indicates that the river discharge significantly fluctuated and that the channels were filled with mud-bearing stratified fine-grained sand by low-density tractional turbulent flow during the high and low water stages and with a massive mud or sandy mud by a high-density flow during the rising and falling stages. The spatial pattern of fluvial channels and deformation channel-fill sandbodies were controlled by the graben topography and the differential compaction of peat substrate, with possible influence of bedrock faults. The fluvial system is thought to have drained to an endorheic ‘terminal’ basin to the north, rather than into the hypothetical Baltic River and further westwards to the distant North Sea basin, as postulated by some previous authors. The present case study contributes to the known spectrum of anastomosing river systems as a sand- to mud-dominated end-member.
EN
Antibacterial properties of 15 titania photocatalysts, mono- and dual-modified with nitrogen and carbon were examined. Amorphous TiO2 , supplied by Azoty Group Chemical Factory Police S.A., was used as titania source (Ar-TiO2 , C-TiO2 , N-TiO2 ;2 and N,C-Ti2 2 calcined at 300°C, 400°C, 500°C, 600°C, 700°C). The disinfection ability was examined against Escherichia coli K12 under irradiation with UV and artificial sunlight and in dark conditions. It has been found the development of new photocatalysts with enhanced interaction ability with microorganisms might be a useful strategy to improve disinfection method conducted under artificial sunlight irradiation. The efficiency of disinfection process conducted under artificial sunlight irradiation with carbon (C-TiO2 ) and carbon/nitrogen (N,C-TiO2 ) photocatalysts was similar as obtained under UV irradiation. Furthermore, during dark incubation, any toxicity of the photocatalyst was noted.
5
Content available Industrial diagnostics system using gamma radiation
EN
During the operation of large industrial installations, a very important task is to maintain the proper technical state. In the event of an emergency, it is vital to locate the place of occurrence as soon as possible. In solving this type of problem, it often helps to apply the methods of measurement associated with ionizing radiation. One of these methods is the gamma scanning. The purpose of this type of measurement is the detection and localization of disturbance of technological processes which may result in incorrect decomposition the flowing medium and workpiece (sediments, congestion) as well as damage to the internal constructions. A particularly: (i) preventive diagnosis – early detection of installation failure; (ii) rationalization of repairs and renovations – to determine the need to take or not to take remedial action; (iii) quick and precise installation inspections – to gain knowledge of the technical condition and technological installations; (iv) indication of worn parts and posing a threat – diagnostics of the technical condition installation; (v) forecasting the useful lifetime of equipment.
PL
W artykule zaprezentowano wyniki badań węglowo-palladowych nanokompozytowych warstw (C-Pd), przeznaczonych do zastosowania w czujnikach wodoru. Warstwy były otrzymywane w procesie PVD jak również w procesie dwustopniowym PVD/CVD. Wykorzystano transmisyjną mikroskopię elektronową (TEM) oraz skaningową mikroskopię elektronową (SEM) do badania topografii i morfologii warstw. Badania zmian rezystancji warstw PVD i PVD/CVD pod wpływem gazu zawierającego 1%H₂/N₂ prowadzono w warunkach normalnych. Poza tym badano zmiany rezystancji w warunkach wilgotności powietrza do 80% oraz w zakresie temperatur od -10 do 70°C. Zastosowano spektroskopię FTIR do stwierdzenia obecności molekuł fullerenu C₆₀ i octanu palladu w warstwach. Strukturę molekularną warstw C-Pd badano za pomocą spektroskopii podczerwieni FTIR. W niektórych warstwach obserwowano obecność pasm przypisanych do fulerenu (są to z reguły warstwy PVD). Natomiast w warstwach z procesu dwustopniowego PVD/CVD obecności tych pasm nie stwierdzono.
EN
The results of some properties studies of carbonaceous-palladium (C-Pd) nanocomposite films that can be applied in hydrogen sensors are presented. These films were obtained by PVD method as well as by two-step process PVD/CVD. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) were used to investigate a topography and a morphology of C-Pd films. The resistivity changes at normal atmosphere and ambient temperature for both kinds of films due to interaction with gas containing 1%H₂/N₂ were measured. The resistivity changes at the temperature range from -10 to 80°C and at humidity up to 80% were also studied. FTIR spectroscopy was used to state the presence of the fullerene C₆₀ and palladium acetate molecules in the film.
PL
Ze względu na silny rozwój technologii wodorowych wzrasta zainteresowanie urządzeniami i materiałami pozwalającymi gromadzić i wykrywać wodór. W szczególności czujniki wodoru mogą znaleźć zastosowanie w wielu dziedzinach życia i techniki. W tej pracy przedstawiamy rezultaty kilkuletniej pracy nad opracowaniem czujnika wodoru nowej generacji wykorzystującego jako element aktywny warstwy węglowo-palladowe. Ten innowacyjny, rezystancyjny czujnik wodoru może pracować w warunkach podwyższonej temperatury i wilgotności. Czujnik taki jest selektywny, charakteryzuje się szybką odpowiedzią i daje wyraźny sygnał nawet dla bardzo niskich koncentracji wodoru.
EN
Rapid development of hydrogen technology caused interest in devices and materials allowing for storage and detection of hydrogen. Especially, hydrogen sensors could be applied in many areas of daily life and technics. In this paper we present results of our studies on a elaboration of construction and material technology for new generation of hydrogen sensor based on carbonaceous-palladium films. This innovative, resistive hydrogen sensor can operated at higher than normal temperature and humidity. This sensor is selective, shows fast response and gives strong signal even at very low concentration of hydrogen.
EN
Changes in superficial and structural properties in carbonaceous–palladium (C–Pd) films prepared by PVD method, induced by annealing them in an inert atmosphere were studied. C–Pd films with different Pd content in a carbon matrix were investigated. SEM observation after heat treatment showed the agglomeration of palladium nanograins into bigger grains and significant changes in a topography and morphology of C–Pd films. XRD studies confirmed the formation of big (more than 100 nm in diameter) Pd nanograins as a result of the annealing process. FTIR studies showed that C–Pd films from PVD process contained fullerene C60 and palladium acetate (films precursors), which were decomposed during the annealing process.
10
Content available remote Rotifer trophic state indices as ecosystem indicators in brackish coastal waters
EN
Thanks to their short life cycles, rotifers react rapidly to changes in environmental conditions and so may be useful for biological monitoring. The objective of this paper was to investigate the applicability of rotifer trophic state indices as indicators of the trophic state of brackish waters, as exemplified by the Vistula Lagoon. Carried out in summer from 2007 to 2011, this study showed no significant correlation between the Lagoon's trophic state and the rotifer structure. This confirms the limited applicability of rotifer trophic state indices for evaluating water quality in brackish water bodies.
PL
Wydrążone nanorurki kwarcowe SiO2 z powodu optycznych właściwości mogą znaleźć zastosowanie, jako jednowymiarowe obiekty w urządzeniach optoelektronicznych, jako fotokatalizatory, nanosensory optyczne, chemiczne lub biologiczne oraz w innych urządzeniach nanoelektronicznych np. jako nośniki informacji. W pracy przedstawiamy sposób wytwarzania wydrążonych nanorurek kwarcowych, zawierających nanopiłki Pd. Metoda syntezy nanorurek kwarcowych polega na wygrzaniu w powietrzu w temperaturze 900°C nanodrutów krzemku palladu Pd2Si otrzymanych w procesie dwustopniowym PVD/CVD. Otrzymane nanorurki SiO2 są wydrążone, w wydrążeniu znajdują się nanozirna Pd o sferycznym kształcie nazwane przez nas nanopiłkami. Nanorurki mają średnicę zewnętrzną kilkudziesięciu nanometrów a długość od 1 do kilkudziesięciu μm.
EN
Hollow silica nanotubes SiO2 due to the optical properties can be used as one-dimensional objectives in optoelectronic devices, as phootocatalysts, optical, chemical or biological sensors and in the other electronics devices as i.e. a data carrier. We present the method of obtaining hollow silica nanotubes containing palladium nanoballs. The method of preparations of these nanotubes consists on the annealing at the temperature of 900°C in the air atmosphere of Pd2Si nanorods. Such nanorods were firstly prepared by two steps PVD/CVD method. These hollow nanotubes contain inside Pd nanoballs. The eternal diameter of nanotubes is about few tens nm and their length changes from 1 to few tens of μm.
12
Content available Wireless system for radiometric measurements
EN
Wireless system for radiometric measurements contains probes, for gamma radiation measurements and other probes for radon concentration measurements in air and water. The probes have the form of droplet-tight cylinders powered from a local battery. Measuring data collecting unit, based on a portable computer, communicates directly with the probes in a wireless manner using the WiFi communication network, or through the internet using mobile phone GSM network. Serial port wire connection is also possible. The local battery ensures at least 14 days of continuous operation of the probes. For long term measurements, the probes can also be powered from solar panels. Construction and operation of the probes are described. Results of scintillation probes investigation are given. Detection efficiency of the developed probes is comparable with the laboratory probes offered in our country.
EN
Joining of metals with ceramics is very difficult, because properties of these materials are very different. One of the methods of improving mechanical strength of the obtained joints is the introduction of an additional interlayer to the joining area. This paper presents the Zr and Cu-rich layers in C and SiC substrates obtained using the high intensity pulsed plasma beams method. The results of Zr plasma modifications were beneficial and similar to the results obtained in previous works with Ti. The measured contact angles were below 90 centigrade. The results with Cu plasma were unfavourable with contact angles close to 180 centigrade. Apart from the sessile-drop test and to extend the range of analysis, the investigated samples were examined by stereoscopic optical microscopy (OM), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDXS), grazing angle X-ray diffraction (GXRD), and Rutherford back scattering (RBS) measurements.
EN
LG Gamma Counter is designed for low activity measurement of the radioactive isotope iodine 125I in liquid or solid samples during radioimmunoassay (RIA) and immunoradiometric assay (IRMA) in small or medium size clinic laboratories. Apart from RIA and IRMA programmed procedures, a measurement of small activity gamma samples is possible. The well scintillator NaI(Tl) is used as radiation detector for the isotope 125 I in the measuring channel, the well dimensions fi being 17 x 38 mm. Gamma Counter was adapted for measuring radioactivity of single samples. The counter is equipped with an automatic system allowing transportation of examined samples to a scintillator well. The gauge is based on an integrated computer which is working under the control of Windows CE and is equipped with special software allowing for setting measurement parameters and communication with an external computer. The measured sample is placed inside the scintillator well either by an automatic sample feeder or manually. The pulses from a photomultiplier tube after amplification and shaping in pulse amplifiers are counted in the window of a single channel analyser by a programmable pulse counter under the control of microprocessor system. The measured count rate is the measure of activity of the assayed sample. Expected count rate error due to unstable operation of amplification is lower than 1%.
EN
Austenitic AISI 304, 316L and ferritic 430 stainless steels were implanted with yttrium to fluences ranging between 1 x 1015 and 5 x 1017 ions/cm2. The samples were subjected to oxidation in air at a temperature of 1000 centigrade for a period of 100 h and next examined by stereoscopic optical microscopy (OM), scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDX) and Rutherford back scattering spectrometry (RBS). The results obtained with the use of ion implantation are discussed.
EN
Study of benthic habitats is significant from ecological and economical point of view. Non–invasive, rapid and relatively cheap methods of the habitat classification are required. It is the reason why the hydroacoustic classification techniques are developed. These techniques are sensitive to the seabed sediments type and the backscattering properties of the benthic habitats, and are developed for individual marine conditions. Last few years the hydroacoustic classification algorithms are developed for the Southern Baltic Sea. To improve the algorithms it is required to know the backscattering properties of the typical benthic individual and aggregated organisms. The main objective of the article is the study of the backscattering characteristics of benthic shelled animals Mytilus edulis trossulus, which is one of the dominant species in the southern Baltic Sea. The approach is based on the numerical modelling of the acoustic wave backscattering by the individual organisms and their aggregations and comparison of the modelling results with the measured backscattered data.
PL
W pracy przedstawiamy dwustopniową metodę syntezy krzemku palladu w postaci nanoigieł. Nanoigły powstają podczas osadzania warstw węglowo-palladowych na podłożach krzemowych, przy wykorzystaniu technik PVD/ CVD. Nanoigły układu Pd-Si charakteryzowano metodami SEM, TEM, XRD oraz mikroanalizą rentgenowską EDX. Określono strukturę krystaliczną i budowę nanoigieł pod względem ich długości, średnicy przekroju poprzecznego oraz składu.
EN
In this paper we present two steps synthesis method of palladium silicide as nanoneedles. This type of nanoneedles is formed on silicon substrates using PVD/CVD technigues. Nanoneedles Pd-Si system were characterized by SEM, TEM, XRD as well as by microanalysis EDX. The crystallographic structure and the construction of nanoneedles in terms of their length, diameters and composition were determined.
PL
W pracy przedstawiono wyniki badań SEM (wraz mikroanalizą) i TEM nowych nanostruktur palladu, otrzymanych podczas wytwarzania warstw nanokompozytowych Pd-C wytworzonych w 2-etapowym procesie technologicznych PVD/CVD przy różnych parametrach tego procesu. Przedstawiane nanoobiekty zostały scharakteryzowane pod względem struktury krystalicznej, składu i formy geometrycznej.
EN
Results of investigation with SEM (completed with microanalysis) and TEM methods of new Pd nanostructures are presented. They are observed in Pd-C nanocomposite films which were obtained in a two-step PVD/CVD process with various parameters. The crystalline structure, geometrical form and composition of presented nanoobjects were described.
19
Content available remote Electron emission from Spindt-like carbon nanotubes field emission cathodes (FECs)
EN
We present field emission characteristics from Spindt-like carbon nanotubes (CNT) films obtained in a two steps method. The two steps method was elaborated in Tele & Radio Research Institute (Poland) and it consists of two independent processes: first, the physical vapour deposition (PVD) process in which a nanocomposite film built of Ni nanocrystals and carbonaceous matrix is prepared; second, the chemical vapour deposition (CVD) process in which the nanocomposite film is modified in high temperature (650 °C) and in atmosphere of hydrocarbons. A field emission property of CNT films is measured using a diode type system. Emission current versus applied field (I-V) is characterized by varying potential from 0 to 4 kV. The results show that emission current and threshold voltage are depended on CNT films morphology and topography - the factors about which technological parameters decide.
EN
A model of detection probe with a plastic scintillator (230 × 105 × 1 mm3) with a ZnS(Ag) layer at the top, and a model with six pancake Geiger-Müller (GM) counters were investigated as alpha particles (Am-241) and beta radiation (Sr-90) contamination detection probes at a dosimetric stand. A detection probe, 166 × 104 mm2 of active area, with a proportional counter was also investigated for comparison. The scintillation probe showed a higher alpha detection efficiency and a comparable beta detection efficiency with respect to the probe containing the proportional counter. The GM probe shoved a higher alpha detection efficiency, and a lower beta detection efficiency than the proportional counter probe. Detection efficiency of the scintillation probe strongly depends on the distance from the photomultiplier tube (PMT) photocathode. Active area of the GM probe of all counters constitutes approximately 50% of its measuring area.
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