Informacja

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

Wyszukujesz frazę "Pérez, M." wg kryterium: Autor


Tytuł:
Bio-methanization of organic fraction from municipal solid waste: temperature effects
Autorzy:
Fernández-Rodríguez, J.
Pérez, M.
Romero, L. I.
Powiązania:
https://bibliotekanauki.pl/articles/779264.pdf
Data publikacji:
2013
Wydawca:
Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
Tematy:
anaerobic digestion
OFMSW
mesophilic
thermophilic
methane
Opis:
The main objective of this study was to analyse the development of dry anaerobic digestion process of OFMSW in batch reactors under two temperature ranges, thermophilic (55°C) and mesophilic (35°C). The experimental results lead to the conclusion that the thermophilic range has a greater rate of hydrolysis and is therefore more effective to degrade wastes, shortening the overall operating time. For example, the hydrolytic step in the thermophilic (T) process lasted an average of 8 days versus 14 days in the mesophilic (M) range. The methanogenic phase lasted for 18 and 29 days in the T and M processes, respectively. The mesophilic range showed higher removal of the organic effluent but with greater uptime requirements. Moreover, the thermophilic range showed greater productivities than the mesophilic range, and the productivities were approximately doubled in terms of the produced biogas from a given amount of consumed organic matter.
Źródło:
Polish Journal of Chemical Technology; 2013, 15, 2; 99-106
1509-8117
1899-4741
Pojawia się w:
Polish Journal of Chemical Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A new capybara from the late Miocene of San Juan Province, Argentina, and its phylogenetic implications
Autorzy:
Cerdeno, E.
Perez, M.E.
Deschamps, C.M.
Contreras, V.H.
Powiązania:
https://bibliotekanauki.pl/articles/20827.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Opis:
A new hydrochoerine rodent, Cardiatherium calingastaense sp. nov. (Caviidae), is described based on the specimen INGEO-PV 87. It was recovered from the late Miocene Las Flores Formation, cropping out at the Puchuzum locality, San Juan Province, Argentina. The new species is based on a particular combination of characters, among which the following can be highlighted: p4 with internal fissures equally deep as in Cardiatherium paranense, secondary external fissure as in Cardiatherium patagonicum, and lacking the fifth internal fissure and supernumerary internal fissure, as in C. paranense; m3 with a conspicuous labial column in the posterior ramus of the second prism; very deep primary and secondary external fissures in upper cheek teeth, the former producing a labial strong step-shaped profile in M2; sagittal crest on the parietals; bullae small in ventral view; scars of the origin of the masseter medialis muscle with an anterior projection up to the level of the incisive foramen and the maxilla-premaxilla suture. The phylogenetic analysis supports the taxonomic proposal of creating a new species of Cardiatherium and shows C. calingastaense sp. nov. as the sister group of the other species of the genus. The lineage leading to the clade Cardiatherium + largest capybaras would have originated at least during the Chasicoan SALMA (early late Miocene). Cardiatherium calingastaense sp. nov. adds to the previous record of Cardiatherium chasicoense and Cardiatherium paranense in the late Miocene of San Juan and Mendoza provinces, respectively, thus increasing the diversity of capybaras in central-west Argentina.
Źródło:
Acta Palaeontologica Polonica; 2019, 64, 1
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Successive Methods for the Separation of Titanium Oxide from the Black Sands of Ecuador
Autorzy:
Perez, S. M.
Sharadqah, S.
Powiązania:
https://bibliotekanauki.pl/articles/123820.pdf
Data publikacji:
2018
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
ion-exchange resin
muisne
Eesmeraldas
Ecuador
black sands
titanium dioxide
Opis:
The black sands found on certain Ecuadorian beaches present a high ilmenite contents up to 50%. In this work, TiO2 was obtained from the black sands of Muisne beaches – Ecuador by combining the thermal, chemical and ion exchange treatments. For the thermal treatment, the raw material was smelted at temperature of 1100 °C using a basic flux. Subsequently, the chemical treatment was initiated in the presence of Fe0 metal using chemical digestion with HCl, and the sample was purified by separating the precipitates from a series of reactions developed at different pHs with NH4OH, Na2S and HCl. The final effluent resulting from the last HCl digestion was purified by ion exchange using Amberlite IRA 400 resin of strongly anionic character. The effluent is then treated in basic medium and the resulting precipitate is calcined. The recovery yield of the TiO2 pigment was 46% with 92% purity.
Źródło:
Journal of Ecological Engineering; 2018, 19, 1; 186-190
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Systematic review of Neocaviafrom the Neogene of Argentina: Phylogenetic and evolutionary implications
Autorzy:
Madozzo-Jaen, M.C.
Perez, M.E.
Montalvo, C.
Tomassini, R.L.
Powiązania:
https://bibliotekanauki.pl/articles/21378.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Instytut Paleobiologii PAN
Opis:
Caviidae is one of the groups of rodents with the greatest ecomorphological disparity, and with currently three known lineages: Caviinae (cuises), Dolichotinae (maras), and Hydrochoerinae (capybaras). Caviinae include small caviids represented by three extant genera (Microcavia, Cavia, and Galea) and three fossils forms (Dolicavia, Palaeocavia, and Neocavia). In Argentina, the fossil record of Caviinae is continuous and abundant since the late Miocene. Neocavia, specifically, is represented by different species recorded in the late Miocene–Pliocene. Here, we describe a new species of Neocavia from the late Miocene–early Pliocene of the Cerro Azul Formation (La Pampa Province, Argentina), and provide a re-description of already known species (Neocavia lozanoi and “Neocavia depressidens”). Also, we perform a more comprehensive review of the genus and include the Neocavia species in a phylogenetic context within Caviinae. We analyze the main patterns of the evolution of the tympanic bullae within Caviidae, and infer about a possible occasional fossorial habit of Neocavia. The morphological and phylogenetic analyses indicate that Neocavia is more closely related to Dolicavia and Microcavia than to the other Caviinae, and confirm the monophyly of the genus, with at least two clearly differentiable species. Since this study cannot confirm the systematic position and validity of “N. depressidens”, we suggest not to use this taxon as a biostratigraphic indicator.
Źródło:
Acta Palaeontologica Polonica; 2018, 63, 2
0567-7920
Pojawia się w:
Acta Palaeontologica Polonica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Directional Ordering in Amorphous $Fe_{43}Ni_{43}Zr_7Cu_1B_6$ Ferromagnetic Alloys
Autorzy:
Varga, M.
Varga, R.
Vojtaník, P.
Hernando, B.
Prida, V.
Santos, J.
Pérez, M.
Powiązania:
https://bibliotekanauki.pl/articles/1533987.pdf
Data publikacji:
2010-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.50.Kj
75.60.Nt
Opis:
Development of the atomic directional ordering in the $Fe_{43}Ni_{43}Zr_7Cu_1B_6$ alloy, during its conventional the same as after transverse magnetic field annealing, was experimentally studied by the amplitude dependence of susceptibility and hysteresis loops measurements, respectively. Diffusion processes of the mobile atoms caused perminvar effect, decrease of the initial susceptibility, increase of the critical field, and linear shape of the hysteresis loop. Uniaxial magnetic anisotropy, created during magnetic field annealing of the FeNiZrCuB alloy, was confirmed also by observation of the surface domain structure.
Źródło:
Acta Physica Polonica A; 2010, 118, 5; 804-806
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Vulnerabilidad socioeconomica y medioambiental: Valle de Cuautitlan-Texcoco, Estado de Mexico
Socioeconomic and environmental vulnerability: Valle de Cuautitlan-Texcoco, State of Mexico
Autorzy:
Hernandez, M.E.O.
Valdez Perez, M.E.
Alvarez Arteaga, G.
Gonzalez Guerrero, G.
Garcia Fajardo, B.
Powiązania:
https://bibliotekanauki.pl/articles/2077806.pdf
Data publikacji:
2019
Wydawca:
Uniwersytet Warszawski. Wydział Geografii i Studiów Regionalnych
Źródło:
Prace i Studia Geograficzne; 2019, 64, 2; 49-67
0208-4589
Pojawia się w:
Prace i Studia Geograficzne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mg-Phosphate Ceramics Produced from the Product of Thermal Transformation of Cement-Asbestos
Magnezowo-fosforanowe wyroby ceramiczne wytwarzane z produktów termicznej transformacji cementu - azbestów
Autorzy:
Perez-Estebanez, M.
Macova, P.
Sasek, P.
Viani, A.
Gualtieri, A.
Powiązania:
https://bibliotekanauki.pl/articles/317820.pdf
Data publikacji:
2014
Wydawca:
Polskie Towarzystwo Przeróbki Kopalin
Tematy:
cement-asbestos
magnesium phosphate ceramics
amorphous
cement-azbest
magnez
fosforyty ceramiczne
bezpostaciowość
Opis:
According to recent European directives, the need for environmentally friendly alternative solutions to landfill disposal of hazardous wastes, such as asbestos-containing materials, prompts their recycling as secondary raw materials. In this work, magnesium phosphate ceramics were prepared using the product of inertization of cement-asbestos. Magnesium phosphate ceramics show interesting properties like good water resistance and high strength that make them attractive materials for several applications. Asbestos containing materials were mixed with magnesium carbonate and annealed at two different temperatures (1100 and 1300 ºC). During thermal treatment complete destruction of asbestos minerals with their transformation into new phases, and crystallization of MgO from magnesium carbonate decomposition, occurs. Upon addition of potassium di-hydrogen phosphate and water, the magnesium oxide in the product of thermal treatment, contributes to the onset of a setting reaction whose product is magnesium potassium phosphate hydrate. The reactivity of periclase was found to be dependent on the calcination temperature. Lower reaction rates were observed for the MgO obtained at lower temperature. The setting reaction of the magnesium phosphate ceramic has been followed in time up to 6 months by means of the X-rays powder diffraction trechnique. Quantitative phase analysis was performed using the Rietveld method and both crystalline and amorphous phases were quantified. The amount of magnesium potassium phosphate was found to increase with time, and was accompained by a decrease in the amount of the amorphous fraction. This fact supports the hypothesis of the formation of an amorphous precursor of the crystalline MKP during the hydration reaction. SEM images showing elongated magnesium potassium phosphate hydrate crystals emerging from what appears as an amorphous matrix, further confirms this view. Since the mechanical properties of magnesium phosphate ceramics are known to increase with time, we can conclude that the main contribution to the development of strenght comes from the crystalline magnesium potassium phosphate hydrate. In this work, we describe a procedure for simultaneous destruction of asbestos minerals and formation of cementitious compounds, which represents a recycling opportunity for this class of hazardous wastes, bringing benefits in terms of energy requirements and preservation of natural resources in cement manufacturing.
Zgodnie z niedawnymi dyrektywami europejskimi, potrzeba przyjaznego dla środowiska alternatywnego rozwiązania usuwania odpadów niebezpiecznych, takich jak materiałów zawierających azbest, pobudza ich ponowne wykorzystanie jako surowców wtórnych. W tej pracy, magnezowo fosforanowe wyroby ceramiczne zostały wytworzone z użyciem produktów inertyzacji cementu – azbestu. Magnezowo fosforanowe wyroby ceramiczne wykazują interesujące właściwości takie jak dobry opór wodny oraz duża wytrzymałość, co sprawia, że są atrakcyjnym materiałem dla wielu aplikacji. Materiały zawierające azbest zostały zmieszanie w węglanem magnezu i wyżarzone w dwóch różnych temperaturach (1100°C i 1300°C). Podczas obróbki cieplnej następuje całkowite zniszczenie minerałów azbestu wraz z ich transformacją w nowe fazy, oraz krystalizacja MgO z rozpadu węglanu magnezu. Podczas dodawania diwodorofosforanu magnezu do wody, tlenek magnezu jako produkt obróbki cieplnej, przyczynia się do rozpoczęcia reakcji wiązania, której produktem jest hydrat fosforanu magnezu i potasu. Odkryto, że reaktywność peryklazu zależy od temperatury kalcynacji. Niższa szybkość reakcji została zaobserwowana dla MgO uzyskanego w niższej temperaturze. Reakcja wiązania wyrobów ceramicznych magnezowo fosforanowych została przeprowadzona w czasie do 6 miesięcy za pomocą techniki rentgenowskiej dyfrakcji proszkowej. Ilościowe analizy fazowe zostały wykonane z użyciem metody Rietvelda i obliczono zarówno fazę krystaliczną jak i amorficzną. Zauważono, że ilość fosforanu magnezowo potasowego zwiększa się w czasie, i że towarzyszy jej spadek ilości części amorficznej. Fakt ten potwierdza hipotezę powstawania amorficznego prekursora krystalicznego fosforanu magnezowo potasowego podczas reakcji hydracji. Obrazy SEM przedstawiają wydłużone kryształy hydratu fosforanu magnezowo potasowego wyłaniające się, z wyglądającej na amorficzną, macierzy, następnie ten wygląd się potwierdza. Ponieważ wiadomo, że właściwości mechaniczne fosforanu magnezu zwiększają się z czasem, możemy wnioskować, że główny wpływ na zwiększenie się wytrzymałości ma krystaliczny hydrat fosforanu magnezowo potasowego. W pracy tej opisano procedurę jednoczesnego rozpadu minerałów azbestu i tworzenia się związków cementytowych, co wskazuje na możliwość powtórnego przetworzenia tego rodzaju odpadów niebezpiecznych, co przynosi korzyści w kategoriach zapotrzebowania energetycznego i ochrony zasobów naturalnych w przetwórstwie cementu.
Źródło:
Inżynieria Mineralna; 2014, R. 15, nr 2, 2; 187-192
1640-4920
Pojawia się w:
Inżynieria Mineralna
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Research object as mechanism for ensuring research experiment reproducibility within virtual research environment
Autorzy:
Krystek, M.
Mazurek, C.
Palma, R.
Pukacki, J.
Gomez-Perez, J. M.
Powiązania:
https://bibliotekanauki.pl/articles/1940554.pdf
Data publikacji:
2017
Wydawca:
Politechnika Gdańska
Tematy:
research object
virtual research environment
Earth Science
semantic web
preservation
evolution
obiekt badawczy
wirtualne środowisko badawcze
nauki o ziemi
sieć semantyczna
ochrona
ewolucja
Opis:
A Research Object (RO) is defined as a semantically rich aggregation of resources that bundles together essential information relating to experiments and investigations. This information is not limited merely to the data used and the methods employed to produce and analyze such data, but it may also include the people involved in the investigation as well as other important metadata that describe the characteristics, inter-dependencies, context and dynamics of the aggregated resources. As such, a research object can encapsulate scientific knowledge and provide a mechanism for sharing and discovering assets of reusable research and scientific knowledge within and across relevant communities, and in a way that supports reliability and reproducibility of investigation results. While there are no pre-defined constraints related to the type of resources a research object can contain, the following usually apply in the context of scientific research: data used and results produced; methods employed to produce and analyze data; scientific workflows implementing such methods; provenance and settings; people involved in the investigation; annotations about these resources, which are essential to the understanding and interpretation of the scientific outcomes captured by a research object. The example research object contains a workflow, input data and results, along with a paper that presents the results and links to the investigators responsible. Annotations on each of the resources (and on the research object itself) provide additional information and characterize, e.g. the provenance of the results. Therefore, exploitation of the RO model should be considered as a way to provide additional reliability and reproducibility of the research. The concept of the RO was introduced to the environment created in the EVER-EST project in the form of Virtual Research Environment (VRE). a group of Earth Scientists, who are observing, analyzing and modeling processes that take place on land and see, was examined against their needs and expectations about the possible improvements in their scientific work. The results show that scientist expectations are focused on knowledge sharing and reuse, and new forms of scholarly communications beyond pdf articles as supporting tools of knowledge cross-fertilization between their members. The Research Object concept seems a natural answer for these needs. However, the model, in order to be sufficient and usable, must become a part of the working environment and needs to be integrated with the actual tools. Therefore, great efforts have been undertaken to create a generic, technical solution – VRE , which implements the expected functionalities. In this article we present a concept of the VRE as a tool that takes advantage of the Research Object model in order to integrate and simplify the information exchange, as well as persist, share and discover assets of the reusable research. Moreover, we are presenting example scenarios of the VRE usage in the four different Earth Science domains.
Źródło:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk; 2017, 21, 4; 379-389
1428-6394
Pojawia się w:
TASK Quarterly. Scientific Bulletin of Academic Computer Centre in Gdansk
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An association between organophosphate pesticides exposure and Parkinsonism amongst people in an agricultural area in Ubon Ratchathani Province, Thailand
Autorzy:
Norkaew, S.
Lertmaharit, S.
Wilaiwan, W.
Siriwong, W.
Perez, H.M.
Robson, M.G.
Powiązania:
https://bibliotekanauki.pl/articles/873417.pdf
Data publikacji:
2015
Wydawca:
Narodowy Instytut Zdrowia Publicznego. Państwowy Zakład Higieny
Tematy:
organophosphate pesticide
human exposure
human disease
cholinesterase activity
Parkinson's disease
agricultural area
Ubon Ratchathani province
Thailand
Opis:
Background. Parkinson’s disease (PD) is a ubiquitous disease. However, PDs prevalence in the population of agricultural communities lacks understanding and there has been no epidemiological study on the association between pesticides exposure factors and risk for PD. Objective. To investigate the potential association between organophosphate pesticides exposure and Parkinsonism by using a screening questionnaire in agricultural areas. Material and Methods. Ninety elderly people living in agricultural areas participated in a cross-sectional study conducted at Tambon Hua-Rua Health Promoting Hospital in April 2014. Screening questionnaires for Parkinson’s disease, Test-mate ChE (Model 400) for blood cholinesterase (ChE) levels of both blood enzymes erythrocyte cholinesterase (AChE), and plasma cholinesterase (PChE) were used as measurement tools. Descriptive statistics for frequencies and percentage distributions were used primarily to summarize and describe the data. Sensitivity, specificity, positive and negative predictive values were calculated. Results. The age range of the participants was 50 to 59 years old, with an average age of 53.9+2.87 years. The majority of the participants were female (62.2%), 82.2% of respondents were farmers. Most of participants (76.7%) reported that they applied insecticides in their farms. Ninety persons participated and completed the 11-item questionnaire. Of these, 17 (18.9%) felt that they lost balance when turning or that they needed to take a few steps to turn right around and 16.7% of participants indicated that they felt the need to move slowly or stiffly. The study found the prevalence of abnormal AChE levels was 28.9% (95%CI=19.81-39.40) and 17.8% of PChE levels (95%CI=10.52-27.26). To predict Parkinsonism, AChE, and PChE level, with a cutoff score of 5 or higher there had to be a sensitivity of 0.31, specificity of 1.00, positive predictive value (PPV) of 1.00 and negative predictive value (NPV) of 0.78 for AChE. While PChE, the score value of 5 or more had a sensitivity of 0.19, specificity of 0.93, PPV of 0.38 and NPV of 0.84. Conclusion. This study described an association between pesticides exposure and Parkinsonism. The questionnaire appears to be useful for Thai agriculturists as a screening tool for Parkinsonism and cholinesterase levels regarding to pesticides exposure.
Źródło:
Roczniki Państwowego Zakładu Higieny; 2015, 66, 1
0035-7715
Pojawia się w:
Roczniki Państwowego Zakładu Higieny
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Chemotaxonomic study on Thymus x toletanus Ladero and its parental species
Autorzy:
Salas, J B
Perez-Alonso, M.J.
Tellez, T.R.
Pardo, F.M.V.
Powiązania:
https://bibliotekanauki.pl/articles/57327.pdf
Data publikacji:
2010
Wydawca:
Polskie Towarzystwo Botaniczne
Tematy:
chemotaxonomy
Thymus x toletanus
parental species
Thymus mastichina
Thymus villosus ssp.lusitanicus
hybrid
plant cultivation
Opis:
We analysed the essential oils of cultivated material of Thymus xtoletanus Ladero and its parents, Th. mastichina (L.) L. and Th. villosus subsp. lusitanicus (Boiss.) Coutinho, with seeds from the same locality in the centre of the Iberian Peninsula. The essential oil of Th. xtoletanus, which had not been analyzed previously, presented 1,8-cineole as the major component (25.5%), as was also the case for Th. mastichina (76.1%). Other components with a major presence in Th. xtoletanus and Th. villosus subsp. lusitanicus were [(Z)-β-ocimene (8.1%); camphor (4.5%); sabinene (3.2%); α-pinene (2.8%)], and [(Z)-β-ocimene (4.1%), camphor (9.8%), sabinene (2.8%), α-pinene (7.1%)], respectively. However, in the hybrid the components β-phelandrene (14.5%), limonene (6.9%), (E)-γ-bisabolene (3.5%), and viridiflorol (3.3%) stood out, inter alia, whereas their presence in the parents was limited. The study confirms the hybrid origin of Th. xtoletanus as intermediate between Th. mastichina and Th. villosus subsp. lusitanicus.
Źródło:
Acta Societatis Botanicorum Poloniae; 2010, 79, 2; 125-128
0001-6977
2083-9480
Pojawia się w:
Acta Societatis Botanicorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Repeatability and reproducibility of dry and wet heat resistance tests according to EN 12721 and EN 12722
Powtarzalność i odtwarzalność badań odporności na ciepło suche i mokre według norm EN 12721 and EN 12722
Autorzy:
Perez, R.M.
Roux, M.-L.
Milla, J.L.
Garcia, S.
Delorme, T.
Lacourt, S.
Powiązania:
https://bibliotekanauki.pl/articles/52760.pdf
Data publikacji:
2012
Wydawca:
Sieć Badawcza Łukasiewicz - Instytut Technologii Drewna
Tematy:
repeatability
reproducibility
dry heat resistance test
wet heat resistance test
EN 12721 standard
EN 12722 standard
European standard
surface resistance
furniture
furniture surface
Opis:
The European Standards 12721 and 12722 specify a method for the assessment of the surface resistance to wet and dry heat of furniture respectively. The aim of the research is to establish data on the test precision of both tests in order that this precision is mentioned on the standards and test reports based on them. It is intended to measure the reproducibility and repeatability according to the standard ISO 5725-2 of data obtained in an international round-robin exercise carried out by eight participating laboratories expert in furniture surfaces. The results presented show that the repeatability variance is almost 0, while the between-laboratory variance is between 0 and 1, according to the order of increment of the assessment rating code.
Normy europejskie 12721 i 12722 określają metodę oceny odporności powierzchni meblowych na mokre i suche ciepło. Celem badań jest ustalenie danych dotyczących precyzji oby rodzajów badań w celu umieszczenia tych informacji w normach i sprawozdaniach z badań opartych na tych normach. Zamierza się dokonać pomiarów powtarzalności i odtwarzalności wyników międzynarodowego badania round-robin przeprowadzonego przez osiem laboratoriów, które specjalizują się w badaniu powierzchni, zgodnie z normą ISO 5725-2. Zaprezentowane wyniki wskazują, że wariancja powtarzalności jest bliska 0, natomiast wariancja pomiędzy laboratoriami mieści się w przedziale 0 i 1, zgodnie z porządkiem wzrostu kodów oceny.
Źródło:
Drewno. Prace Naukowe. Doniesienia. Komunikaty; 2012, 55, 187
1644-3985
Pojawia się w:
Drewno. Prace Naukowe. Doniesienia. Komunikaty
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The essential oil of the protected species: Thymus praecox ssp. penyalarensis
Autorzy:
Salas, J.B.
Tellez, T.R.
Pardo, F.M.V.
Perez-Alonso, M.J.
Capdevila, M.A.C.
Powiązania:
https://bibliotekanauki.pl/articles/57194.pdf
Data publikacji:
2012
Wydawca:
Polskie Towarzystwo Botaniczne
Tematy:
essential oil
protected species
Thymus praecox ssp.penyalarensis
endemism
threatened species
chemical composition
Lamiaceae
plant species
Opis:
The essential oil of a protected Spanish species, Thymus praecox ssp. penyalarensis, was firstly analyzed [Gas Chromatography-Mass Spectrometry (GC-MS)] from wild populations during the phenological stages of flowering and fruiting. In flowering, the yield was 1.2%, and the major components were identified as thymol (18.5%), p-cymene (14.6%), carvacrol (11.6%), and γ-terpinene (10.1%). In fruiting, the yield was 0.9% and the major components resulted to be p-cymene (19.0%), carvacrol (16.5%), and borneol (10.5%). An experimental cultivation of the taxa was made also in order to analyze its essential oil as well. The yield was 1.3%, and the main compounds were thymol (19.1%), p-cymene (17.0%), and γ-terpinene (12.3%). Finally, the composition of the essential oil of this plant is discussed in relation to chemotaxonomic and biogeographical aspects.
Źródło:
Acta Societatis Botanicorum Poloniae; 2012, 81, 1
0001-6977
2083-9480
Pojawia się w:
Acta Societatis Botanicorum Poloniae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A time-domain pulse amplitude and width discrimination method for photon counting
Autorzy:
del Mar Correa, M.
Pérez, F. R.
Powiązania:
https://bibliotekanauki.pl/articles/220971.pdf
Data publikacji:
2018
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
field-programmable gate array
time-to-digital converter
spectroscopy
photomultiplier
photon counting
discriminator
after-pulsing
low-voltage differential signalling
Opis:
This work shows a time-domain method for the discrimination and digitization of parameters of voltage pulses coming from optical detectors, taking into account the presence of electronic noise and afterpulsing. Our scheme is based on an FPGA-based time-to-digital converter as well as an adjustable-threshold comparator complemented with commercial elements. Here, the design, implementation and optimization of a multiphase TDC using delay lines shorter than a single clock period is also described. The performance of this signal processing system is discussed through the results from the statistical code density test, statistical distributions of measurements and information gathered from an optical detector. Unlike dual voltage threshold discriminators or constant-fraction discriminators, the proposed method uses amplitude and time information to define an adjustable discrimination window that enables the acquisition of spectra.
Źródło:
Metrology and Measurement Systems; 2018, 25, 2; 269-282
0860-8229
Pojawia się w:
Metrology and Measurement Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Redefinition of the scarcity price: lessons and recommendations from the Colombian Electricity Market
Autorzy:
Llanos-Pérez, E. J.
Hinestroza-Olascuaga, L. M.
Powiązania:
https://bibliotekanauki.pl/articles/136158.pdf
Data publikacji:
2017
Wydawca:
EEEIC International Barbara Leonowicz Szabłowska
Tematy:
Columbia
energy system
energy market
energy planning
market price
Opis:
The Colombian government introduced a capacity market in order to promote the diversification in the energy matrix and protect users from high prices derived from dry seasonal events. Unfortunately, the flaws in the scarcity price definition- a mechanism that activates the capacity market obligation and sets a cap price for the spot market- have led into a market failure. Specifically, some generation plants have been forced to be unavailable because their variable costs are significantly higher than the scarcity price. This paper presents a qualitative and quantitative analysis of the Colombian Electricity system, with a particular emphasis on the definition of the scarcity price. Results present lessons and recommendations for policy makers based on the experience of the Colombian Electricity Market, highlighting the need of a new definition of the scarcity price and a different focus on the energy planning scheme.
Źródło:
Transactions on Environment and Electrical Engineering; 2017, 2, 1; 19-26
2450-5730
Pojawia się w:
Transactions on Environment and Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
s,p-d Exchange Constants of CdFeSe Semimagnetic Semiconductor
Autorzy:
Arciszewska, M.
Pakuła, K.
Perez, I.
Twardowski, A.
Powiązania:
https://bibliotekanauki.pl/articles/1886791.pdf
Data publikacji:
1991-02
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
71.25.Tn
71.70.Gm
71.35.+z
Opis:
We report determination of s, p-d exchange constants for hexagonal CdFeSe combining exciton splitting and magnetization measurements performed on the same samples.
Źródło:
Acta Physica Polonica A; 1991, 79, 2-3; 345-348
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
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