Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "Silva, R." wg kryterium: Autor


Tytuł:
Combined Analyses of Ion Beam Synthesized Layers in Porous Silicon
Autorzy:
Ramos, A. R.
Pászti, F.
Horváth, Z. E.
Vázsonyi, É.
Conde, O.
da Silva, M. F.
da Silva, M. R.
Soares, J. C.
Powiązania:
https://bibliotekanauki.pl/articles/2028988.pdf
Data publikacji:
2001-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.10.-i
61.18.Bn
61.43.Gt
68.55.Ln
Opis:
High dose ion implantation was used to form polycrystalline silicide films on porous silicon with different native concentrations of light impurities (C and O). Porous silicon layers severalμm thick were implanted with 170 keV Cr$\text{}^{+}$ ions to fluences of 3×10$\text{}^{17}$ ions/cm$\text{}^{2}$ both at room temperature and 450ºC. Similar samples were implanted with 100 keV Co$\text{}^{+}$ ions to fluences of 2×10$\text{}^{17}$ ions/cm$\text{}^{2}$ at room temperature, 350ºC, and 450ºC. The formed silicide compounds were studied by Rutherford backscattering spectrometry, elastic recoil detection, glancing incidence X-ray diffraction, and four point-probe sheet resistance measurements. Selected Co implanted samples were analysed by cross-section transmission electron microscopy. Results show that the light impurities were partially expelled from the forming silicide layer. Combining cross-section transmission electron microscopy with ion beam methods it was possible to show that, in the implanted region, the porous structure collapses and densifies during implantation, but the underlying porous silicon remains intact. The layer structure, as well as the quality and type of the formed silicide, were found to depend on the original impurity level, implantation temperature, and annealing.
Źródło:
Acta Physica Polonica A; 2001, 100, 5; 773-780
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Loads on walls and inserts in a mass-flow silos
Autorzy:
Ding, S.
Wójcik, M.
Jecmenica, M.
Silva de, S. R.
Powiązania:
https://bibliotekanauki.pl/articles/1955779.pdf
Data publikacji:
2003
Wydawca:
Politechnika Gdańska
Tematy:
silo flow/loads
insert
Lagrangian-Eulerian
adaptive
fillet
Opis:
A finite element analysis has been carried out to investigate flow patterns and loads on silos either with a ralatively steep hopper, or with a shallow hopper but in the presence of an insert. A Lagrangian-Eulerian approach was first adopted to simulate the material flow pattern, with the precondition that mass flow was obtained. It was then attempted to predict the loads exerted by granular materials on the walls of such silos. The load on the insert was also simulated. Techniques such as the adoption of adaptive meshes and filleting along sharp corners were applied in the analysis to overcome the difficulties usually encountered with large deformations in the FEM and the mathematic singularity presented by the abruptness of geometry. Filleting proved to be necessary to bring down the pressure peak at the transition level. The insert took over a significant part of the loads. Comparison with the classic theories have confirmed that the loads predicted on the wall agree quite well with the theoretical results in the silo's cylinder section, but that differences exist in the hopper section; the difference is greater when the hopper is shallower. It has also shown the limitations of predicting flow patterns of granular materials with the traditional elastic-plastic model; a more advanced model is needed.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2003, 7, 4; 525-538
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Linear-wavelet networks
Autorzy:
Galvao, R. K. H.
Becerra, V. M.
Calado, J. M. F.
Silva, P. M.
Powiązania:
https://bibliotekanauki.pl/articles/907399.pdf
Data publikacji:
2004
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
sieć falkowa
model nieliniowy
analiza regresji
identyfikacja systemu
wavelet networks
nonlinear models
regression analysis
system identification
Opis:
This paper proposes a nonlinear regression structure comprising a wavelet network and a linear term. The introduction of the linear term is aimed at providing a more parsimonious interpolation in high-dimensional spaces when the modelling samples are sparse. A constructive procedure for building such structures, termed linear-wavelet networks, is described. For illustration, the proposed procedure is employed in the framework of dynamic system identification. In an example involving a simulated fermentation process, it is shown that a linear-wavelet network yields a smaller approximation error when compared with a wavelet network with the same number of regressors. The proposed technique is also applied to the identification of a pressure plant from experimental data. In this case, the results show that the introduction of wavelets considerably improves the prediction ability of a linear model. Standard errors on the estimated model coefficients are also calculated to assess the numerical conditioning of the identification process.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2004, 14, 2; 221-232
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Vortex Motion and Quasiparticle Resistivity in Superconductors at Microwave Frequencies
Autorzy:
Sarti, S.
Amabile, C.
Fastampa, R.
Giura, M.
Silva, E.
Pompeo, N.
Powiązania:
https://bibliotekanauki.pl/articles/2047225.pdf
Data publikacji:
2007-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.25.Nf
74.20.De
74.60.Ge
74.70.Ad
74.72.-h
Opis:
At nonzero frequencies both the normal and superfluid fractions, as well as moving vortices, contribute to the electrical transport, resulting in intricate expressions for the resistivity. We present an extended study of microwave resistivity data measured on YBa$\text{}_{2}$Cu$\text{}_{3}$O$\text{}_{7-δ}$, SmBa$\text{}_{2}$ Cu$\text{}_{3}$O$\text{}_{7-δ}$, and MgB$\text{}_{2}$ by means of a broad-band technique between 2 and 20 GHz and of a resonant system at 50 GHz. We discuss the main experimental fingerprints that allow one to identify the relevance of the different contributions from the measured microwave response as a function of frequency, temperature, and magnetic field. We show that the field-dependent superfluid/quasiparticles dynamics cannot be in general neglected with respect to the vortex motion, albeit its relative importance is different in different materials: in high temperature superconductors vortex motion prevails at high fields, but at low fields a significant superfluid/quasiparticle contribution exists (ascribed to the presence of lines of nodes). In MgB$\text{}_{2}$ the two contributions are comparable even at high fields. In this general frame, we derive from the measurements vortex and superfluid parameters in agreement with theoretical predictions and independent measurements.
Źródło:
Acta Physica Polonica A; 2007, 111, 1; 87-93
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Development and production of radioactive sources used for cancer treatment in Brazil
Autorzy:
Rostelato, M. E. C. M.
Rela, P. R.
Zeituni, C. A.
Feher, A.
Manzoli, J. E.
Moura, J. A.
Moura, E. S.
Silva, C. P. G.
Powiązania:
https://bibliotekanauki.pl/articles/148305.pdf
Data publikacji:
2008
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
radioactive sources production
iodine-125 seeds
iridium-192 wires
brachytherapy
cancer treatment
Opis:
The number of cancer patients in Brazil is increasing and part of the patients are submitted to brachytherapy treatment using iridium-192 wire and iodine-125 radioactive seeds. The Nuclear Energy Research Institute established a programme to produce iridium-192 wire and iodine-125 radioactive seeds. With the purpose of settling a laboratory for iridium-192 sources production, a wire activation method was developed and a hot cell for the wire manipulation, quality assurance and packaging was built. The iodine-125 seeds consist of a welded titanium capsule containing iodine-125 adsorbed onto a silver rod. Concerning the setup of the local production, the following activities were carried out: superficial treatment of the silver rod, development of a process to absorb the iodine in the silver rod, welding methodology to seal the seeds, leakage and contamination test and source activity measurement.
Źródło:
Nukleonika; 2008, 53, suppl. 2; 99-103
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Recent studies of irradiated mangoes in Brazil : a trend towards commercial approach
Autorzy:
Sabato, S. F.
Silva, J. M.
Cruz, J. N.
Broisler, P. O.
Rela, P. R.
Salmieri, S.
Lacroix, M.
Powiązania:
https://bibliotekanauki.pl/articles/148822.pdf
Data publikacji:
2008
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
gamma radiation
mangoes
physicochemical properties
sensory evaluation
Opis:
Mango is an important commodity to our country as Brazil is a great producer and exporter of tropical fruits. Nowadays, Mexico and India are the main exporters of mango in the world and Brazil occupies the third position in this ranking. As these countries have adopted gamma radiation as a phytosanitary treatment and signed a bilateral agreement with the United States for exporting mango to this country, Brazil has to be up-to-dated with this trend. The Institute of Nuclear and Energy Researches together with field producers in the northeastern region and partners like the International Atomic Energy Agency, the Canadian Irradiation Center and Empresa Brasileira de Agropecuária joined to demonstrate this technology, its application and its commercial feasibility. The whole project was structured in two parts that involved around 1300 mangoes. The first step consisted mainly in studying the quality of irradiated mangoes within our territory, using a multipurpose semi-commercial cobalt facility, and comparing two harvesting points of the fruits. The second one was an international consignment of irradiated fruits from Brazil to Canada, where the control sample consisted of fruits treated with a hot water dip. The financial part of the feasibility study covers the scope of the investment, including the net working capital and production costs. In a summarized way to express, the results from physicochemical analysis and sensory evaluation were favorable, indicating that gamma radiation is a potential quarantine treatment.
Źródło:
Nukleonika; 2008, 53, suppl. 2; 77-79
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Development of an irradiation system for a small size continuous run multipurpose gamma irradiator
Autorzy:
Calvo, W. A. P.
Rela, P. R.
Napolitano, C. M.
Kodama, Y.
Omi, N. M.
da Costa, F.
de Andrade e Silva, L. G.
Powiązania:
https://bibliotekanauki.pl/articles/148041.pdf
Data publikacji:
2009
Wydawca:
Instytut Chemii i Techniki Jądrowej
Tematy:
multipurpose irradiator
gamma irradiator
compact irradiator
cobalt-60 irradiator
gamma facility
Opis:
The Radiation Technology Center from IPEN-CNEN/SP, Brazil, developed a revolutionary design and national technology, a small-sized continuous run and multipurpose industrial gamma irradiator, to be used as a demonstration facility for manufacturers and contract service companies, which need economical and logistical in-house irradiation system alternatives. Also, to be useful for supporting the local scientific community on development of products and process using gamma radiation, assisting the traditional and potential users on process validation, training and qualification of operators and radioprotection officers. The developed technology for this facility consists of a continuous tote box transport system, comprising a single concrete vault, where the automated transport system of products inside and outside of the irradiator utilizes a rotating door, integrated with the shielding, avoiding the traditional maze configuration. Covering 76 m2 of floor area, the irradiator design is a product overlap sources and the maximum capacity of cobalt-60 wet sources is 37 PBq. The performed qualification program of this multipurpose irradiator was based on AAMI/ISO 11137 standard, which recommends the inclusion of the following elements: installation and process qualification. The initial load of the multipurpose irradiator was 3.4 PBq with 13 cobalt-60 sources model C-188, supplied by MDS Nordion – Canada. For irradiator dose optimization, the source distribution was done using the software Cadgamma developed by IPEN-CNEN/SP. The polymethylmetacrylate (PMMA) dosimeter system, certified by the International Dose Assurance Service (IDAS) of the International Atomic Energy Agency (IAEA) was used for irradiator dose mapping. The economic analysis, performance concerning with dose uniformity and cobalt-60 utilization efficiency were calculated and compared with other commercial gamma irradiators available on the market.
Źródło:
Nukleonika; 2009, 54, 2; 93-97
0029-5922
1508-5791
Pojawia się w:
Nukleonika
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Hierarchical Multiobjective Routing in MPLS Networks with Two Service Classes - A Meta-Heuristic Solution
Autorzy:
Girao-Silva, R.
Craveirinha, J.
Clímaco, J.
Powiązania:
https://bibliotekanauki.pl/articles/308908.pdf
Data publikacji:
2009
Wydawca:
Instytut Łączności - Państwowy Instytut Badawczy
Tematy:
multiobjective optimization
MPLS-Internet
routing models
simulated annealing
tabu search
Opis:
The paper begins by reviewing a two-level hierarchical multicriteria routing model for MPLS networks with two service classes (QoS and BE services) and alternative routing, as well as the foundations of a heuristic resolution approach, previously proposed by the authors. Afterwards a new approach, of meta-heuristic nature, based on the introduction of simulated annealing and tabu search techniques, in the structure of the dedicated heuristic, is described. The application of the developed procedures to a benchmarking case study will show that, in certain initial conditions, this approach provides improvements in the final results especially in more "difficult" situations detected through sensitivity analysis.
Źródło:
Journal of Telecommunications and Information Technology; 2009, 3; 20-37
1509-4553
1899-8852
Pojawia się w:
Journal of Telecommunications and Information Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of meteorological parameters in hourly patterns of grass [Poaceae] pollen concentrations
Autorzy:
Munoz, Rodriguez A F
Silva Palacios, I.
Tormo Molina, R.
Powiązania:
https://bibliotekanauki.pl/articles/50296.pdf
Data publikacji:
2010
Wydawca:
Instytut Medycyny Wsi
Tematy:
Poaceae
grass
pollen
pollen concentration
meteorological parameter
pollination
pollen allergy
hourly pattern
Źródło:
Annals of Agricultural and Environmental Medicine; 2010, 17, 1; 87-100
1232-1966
Pojawia się w:
Annals of Agricultural and Environmental Medicine
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Spatial analysis of vegetal cover and sediment yield in Tapacura river catchment based on remote sensing and GIS
Analiza przestrzenna ilosci sedymentu oraz pokrywy roslinnej w zlewni rzeki Tapacura okreslona na podstawie zdalnych obserwacji oraz analizy GIS
Autorzy:
Silva, R M
Santos, C.A.G.
Gico Lima Montenegro, S.M.
Silva, L.P.
Powiązania:
https://bibliotekanauki.pl/articles/81843.pdf
Data publikacji:
2010
Wydawca:
Szkoła Główna Gospodarstwa Wiejskiego w Warszawie. Wydawnictwo Szkoły Głównej Gospodarstwa Wiejskiego w Warszawie
Tematy:
spatial analysis
vegetation cover
sediment yield
Tapacura River
catchment
remote sensing
GIS analysis
Opis:
Mapping and assessment of erosion risk is an important tool for planning of natural resources management, allowing researchers to propose modifi cation in land-use properly and implement more sustainable management strategies in the long-term. The Tapacurá river catchment, located in Pernambuco State, Northeastern Brazil, is one of the planning units for management of water resources of Recife Metropilitan Region (RMR), and it is divided into 12 sub-basins. The objective of this study is to evaluate the spatial variability of vegetal cover and sediment yield in this basin through remote sensing and GIS techniques. Maps of the erosivity (R), erodibility (K), topographic (LS), cover-management (C) and support practice (P) factors were derived from the digital elevation model (DEM), climate database, and soil and NDVI maps, taking into account information available in the literature. In order to validate the simulation process, Sediment Delivery Ratio (SDR) was estimated. The obtained NDVI map showed vegetation loss during the analyzed period, indicating a distinct contrast between loss and gains of vegetation index. The vegetation and sediment yield mapping showed to be a useful tool for environmental monitoring and management, which can provide satisfactory results when jointly used. The results suggest a mean SDR around 0.9 and estimate the sediment yield as 23.98 ton/ha/month.
Analiza przestrzenna ilości sedymentu oraz pokrywy roślinnej w zlewni rzeki Tapacura określona na podstawie zdalnych obserwacji oraz analizy GIS. Artykuł przedstawia sposób wykorzystania zebranych w terenie danych dotyczących pokrywy roślinnej oraz ilości sedymentu określonego za pomocą zdalnych obserwacji oraz analizy GIS w celu monitorowania środowiska i zarządzania zlewniami. W pracy wykorzystano metodę USLE-SDR, a także cyfrowy model terenu. Badania prowadzono w zlewni rzeki Tapacura w północno-wschodniej Brazylii. Wyniki sugerują przyjęcie wartości parametru SDR = 0,9, a oszacowana wielkość transportu rumowiska wynosi 23,98 t/ha/miesiąc.
Źródło:
Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation; 2010, 42, 1; 5-16
0208-5771
Pojawia się w:
Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The pustulated temnospondyl revisited - a plagiosternine plagiosaurid from the Lower Triassic of Brasil
Autorzy:
Dias-Da-Silva, S
Milner, A.R.
Powiązania:
https://bibliotekanauki.pl/articles/23465.pdf
Data publikacji:
2010
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Tematy:
temnospondyl
plagiosternine plagiosaurid
Lower Triassic
Triassic
paleontology
Brazil
plagiosaurid
systematics
morphology
Opis:
A recent contribution published in this journal (Dias−daSilva and Ilha 2009) reported a dermal skull fragment indicating the presence of a putative plagiosauroid temnospondyl in the Lower Triassic Sanga do Cabral Formation of the Paraná Basin, Southern Brazil. The taxonomic assignation of this specimen was necessarily tentative as it was based on circumstantial evidence, specifically the presence of a dense pustular ornamentation over four partial dermal skull bones, consideration of the described taxa known to bear such ornamentation, and the stratigraphic and paleobiogeographic range of such taxa. Therefore, Diasda−Silva and Ilha (2009) could not be totally certain about the plagiosauroid affinities of the new specimen and ascribed it to ?Plagiosauridae. It was particularly difficult to make a precise osteological identification of the specimen and six alternative osteological interpretations were made in comparison to both Gerrothorax and Peltobatrachus (see Dias−da−Silva and Ilha 2009: fig. 2). In spite of the poor taxonomic resolution, the new specimen raised interesting questions regarding the presence of plagiosauroid stereospondyls in western Gondwana, as well as their evolutionary patterns, biostratigraphic and paleobiogeographic implications. After Dias−da−Silva and Ilha's (2009) contribution was published, new data from Damiani et al. (2009) raised the possibility of narrowing down the taxonomic identity of the plagiosauroid from Brazil. Accordingly, this brief report provides a more precise taxonomic assignation for this material.
Źródło:
Acta Palaeontologica Polonica; 2010, 55, 3; 561-563
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Thermal assisted switching magnetic tunnel junctions as FPGA memory elements
Autorzy:
Silva, V.
Fernandes, J. R.
Oliveira, L. B.
Neto, H. C.
Ferreira, R.
Freitas, S.
Freitas, P. P.
Powiązania:
https://bibliotekanauki.pl/articles/397855.pdf
Data publikacji:
2010
Wydawca:
Politechnika Łódzka. Wydział Mikroelektroniki i Informatyki
Tematy:
MRAM (oporność magnetyczna pamięci o dostępie swobodnym)
MTJ (magnetyczny tunel połączeń)
pisanie projektów (programów)
FIMS (pole indukowane magnetycznym przełącznikiem)
MRAM (magnetoresistive random access memory)
MTJ (magnetic tunnel junction)
writing schemes
FIMS (field induced magnetic switching)
TAS (thermal assisted switching)
STT
Opis:
This paper presents our research and development work on new circuits and topologies based on Magnetic RAM for use as configuration memory elements of reconfigurable arrays. MRAM provides non volatility with cell areas and with access speeds comparable to those of SRAM and with lower process complexity than FLASH memories. The new memory cells take advantage of the Thermal Assisted Switching (TAS) writing technique to solve the drawbacks of the more common Field Induced Magnetic Switching writing technique. The CMOS circuit structures to implement the main components for reading and writing the MTJ cells have been developed, characterized and evaluated. A scaled down prototype of a coarse grain reconfigurable array that employs the TAS-MRAM elements as configuration memory has been designed and electrically simulated pre- and post- layout. The results obtained for all the circuit elements, namely the storage cells and the current generators, indicate that the new configuration memory cells can provide a very promising technological solution for run-time reconfigurable hardware devices. The prototype has been manufactured using a standard process 0.35μm 4-Metal CMOS process technology and should be under test in the foreseeable future.
Źródło:
International Journal of Microelectronics and Computer Science; 2010, 1, 1; 31-36
2080-8755
2353-9607
Pojawia się w:
International Journal of Microelectronics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Attachment of 2,2-bipyridine onto a silica gel for application as a sequestering agent for copper, cadmium and lead ions from an aqueous medium
Autorzy:
Souza, E. J.
Cristante, V. M.
Padilha, P. M.
Jorge, S. M. A.
Martines, M. A. U.
Silva, R. I. V.
Carmo, D. R.
Castro, G. R.
Powiązania:
https://bibliotekanauki.pl/articles/779827.pdf
Data publikacji:
2011
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:
2,2-bipirydyna
żel krzemionkowy
adsorpcja
jony metali
2,2'-bipyridine
silica gel
adsorption
metal ions
Opis:
A method was developed to attach 2,2-bipyridine (BP) onto a silica gel surface by a two-step reaction. The fi rst step consisted of a reaction between the matrix and a silylating agent, 3-chloropropyltrimethoxysilane. In the second step of the reaction, a ligand molecule was attached onto Si-CPTS, yielding the product Si-BP. The modified material contained 0.431±0.01 mmol of 2,2-bipyridine per gram of modified silica, as confirmed by FT-IR spectra of the proposed structure. The surface modification was characterized by the BET technique, which revealed a decrease in the surface area from 614 to 450 m2 g-1. The series of adsorption isotherms for the metal ions were adjusted to fit a modified Langmuir equation. The maximum number of moles of copper, cadmium and lead ions adsorbed was 0.64, 0.53, and 0.54 mmol g-1, respectively. The surface saturation was calculated as ¢ fraction and the values obtained, Cu(II) =1.160, Cd(II) = 1.044 and Pb(II) = 0.997, suggest a type 1:1 metal-ligand complex.
Źródło:
Polish Journal of Chemical Technology; 2011, 13, 4; 28-33
1509-8117
1899-4741
Pojawia się w:
Polish Journal of Chemical Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
First Record of Testate Amoebae on Glaciers and Description of a New Species Puytoracia jenswendti nov. sp. (Rhizaria, Euglyphida)
Autorzy:
Santibáñez, Pamela A.
Kohshima, Shiro
Scheihing, Rodrigo A.
Silva, Ricardo
Jaramillo M, Jorge I.
Labarca P, Pedro J.
Casassa R., Gino
Powiązania:
https://bibliotekanauki.pl/articles/763674.pdf
Data publikacji:
2011
Wydawca:
Uniwersytet Jagielloński. Wydawnictwo Uniwersytetu Jagiellońskiego
Tematy:
Glacier, Firn core, Testate amoebae, Trinematidae, Trinema, Puytoracia
Opis:
This study documents for the first time the presence of testate amoebae on glaciers. Three shallow firn cores of 10 m depth were obtained from the Mocho-Choshuenco and Osorno volcanoes, Southern Andes, Chile, in October and November, 2005. Euglyphid testate amoebae were detected in 28 samples that correspond to the spring-summer layers of the firn cores. Inspection of 454 collected individuals reveals the presence of four different taxa. Three of these taxa, Trinema lineare, Trinema enchelys and Puytoracia bergeri have previously been reported in ice-free environments. The fourth taxon corresponds to a new species Puytoracia jenswendti nov. sp. The observation of food content and reproductive activities in a significant fraction of specimens evidence that testate amoebae are competent to inhabit glaciers. The testate amoebae found in the firn cores display clear seasonal variations in abundance indicating that these records can provide a new and novel proxy as paleoindicator for firn/ice core dating and for estimation of past glacier mass balance.
Źródło:
Acta Protozoologica; 2011, 50, 1
1689-0027
Pojawia się w:
Acta Protozoologica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Noise Exposure Levels of Priests and Worshippers in Protestant Churches
Autorzy:
Silva, L. F.
Cabral, R.
Powiązania:
https://bibliotekanauki.pl/articles/90659.pdf
Data publikacji:
2011
Wydawca:
Centralny Instytut Ochrony Pracy
Tematy:
noise
exposure
churches
worship
Opis:
Context. Worship in Protestant churches in Brazil is very noisy. Thus, this practice may pose a hearing risk. Aims. To evaluate the priests’ and worshippersʼ noise exposure during worship. Settings and design. The analysis was carried out in 5 churches located in the city of São José dos Campos, Brazil. Methods and material. To estimate the worshippers’ noise exposure, an author of this study was also submitted to dosimetry. The methodology was based on Fundacentro’s Occupational Hygiene Standard No. NHO-01 (2001). Weekly noise exposure was estimated according to the priest’s information about the number of services in the period. Results. The priest’s noise exposure was over the recommended limits. The normalized exposure level varied between 95.4 to 99.5 dB(A). In 2 of the churches, the noise exposure registered, with values of 85.3 and 86.5 dB(A), may also pose risk to the worshippers. Conclusions. Worship in the churches generated sound pressure levels that imply health risk, especially to priests, so hearing conservation programs with adequate acoustical sanitation measures must be implemented there.
Źródło:
International Journal of Occupational Safety and Ergonomics; 2011, 17, 1; 79-86
1080-3548
Pojawia się w:
International Journal of Occupational Safety and Ergonomics
Dostawca treści:
Biblioteka Nauki
Artykuł

Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies