Search results for "position"
showing 10 items of 6771 documents
Enemmän kuin kymmenen näkökulmaa esiintymiseen
2022
Kirja-arvio teoksesta Poutiainen, S. (toim.) 2021. Yleisö ja puhe – Kymmenen näkökulmaa esiintymiseen. Kulttuuriosuuskunta Partuuna: Helsinki
Spektrofotometryczna metoda oznaczania składu kopolimerów etylen/1-heksen
2000
Zmodyfikowano znaną z literatury spektrofotometryczną (FT-IR) metodę oznaczania składu kopolimerów etylenu z α-olefinami i wykorzystano ją do oznaczania składu kopolimerów etylenu z 1-heksenem o bardzo dużym ciężarze cząsteczkowym (~ 106) (tabela 1). Wyprowadzono zależność umożliwiającą obliczenie zawartości 1-heksenu w kopolimerach etylen/1-heksen na podstawie stosunku wartości absorbancji pasm ACH31379 / ACH21369 [równanie (8)] oznaczonych po separacji odpowiednich pasm analitycznych (rys. 7 i 8). Ustalono też, że absorbancji pasm z zakresu 722 cm-1 nie powinno się wykorzystywać w proponowanej metodzie ilościowej (tabela 1).
Total volatile flux from Mount Etna
2008
[1] The Total Volatile (TV) flux from Mount Etna volcano has been characterised for the first time, by summing the simultaneously-evaluated fluxes of the three main volcanogenic volatiles: H2O, CO2 and SO2. SO2 flux was determined by routine DOAS traverse measurements, while H2O and CO2 were evaluated by scaling MultiGAS-sensed H2O/SO2 and CO2/SO2 plume ratios to the UV-sensed SO2 flux. The time-averaged TV flux from Etna is evaluated at ∼21,000 t·day−1, with a large fraction accounted for by H2O (∼13,000 t·day−1). H2O dominates (≥70%) the volatile budget during syn-eruptive degassing, while CO2 and H2O contribute equally to the TV flux during passive degassing. The CO2 flux was observed to…
Chemical mapping of a fumarolic field: La Fossa Crater, Vulcano Island (Aeolian Islands, Italy)
2005
[1] The performance of a newly-developed portable gas analyzer, capable of real-time measurement of CO2, SO2 and H2S concentrations in volcanic gases, was tested at La Fossa Crater, Vulcano Island. The gas analyzer was used to acquire about 3000 determinations over the fumarolic field, allowing the definition of its chemical structure and heterogeneity. Our high-resolution analysis reveals that, in December 2004, the La Fossa fumarolic field was characterized by an oxidized inner core (SO2/H2S ratios of ∼3), and by more reducing conditions on its northern edge (SO2/H2S ratios of ∼1; range: 0.2–3.3). CO2/(SO2+H2S) molar ratios averaged 35 ± 21, with overlapping compositions for rim and inner…
First multi-GAS based characterisation of the Boiling Lake volcanic gas (Dominica, Lesser Antilles)
2013
We used a Multi-component Gas Analyser System (Multi-GAS) to measure, for the very first time, the composition (H2O, CO2, H2S, SO2) of the volcanic gas plume issuing from the Boiling Lake, a vigorously degassing, hot (T ~ 80-90°C) volcanic lake in Dominica, West Indies. The Multi-GAS captured in-plume concentrations of H2O, CO2 and H2S were well above those typical of ambient atmosphere, while no volcanic SO2 was detected (<0.05 ppm). These were used to derive the Boiling Lake plume characteristic ratios of CO2/H2S (5.2±0.4) and H2O/CO2 (31.4±6). Assuming that other volcanic gas species (e.g., HCl, CO, H2, N2, etc.) are absent in the plume, we recalculated a (air-free) composition fo…
Observaciones sobre algunos caracteres de valor taxonómico en el grupo de los carófitos
1990
The variability of the microstructurals characters and mineralogical composition of the oogonia of some charophytes extant and fossils is described. Two types of microstructures (W & V) are find. These are conservative into populations and are not able to change by the environmental factors. Moreover, these structures are quite constant in some of the phylogenetics groups studied. Consequently it is proposed its utilization in taxonomy. The apparition of original compounds in the Charophyta (vaterite. whewelite, aragonite, etc.) is important because it supports an old idea that considerates the Charophyta as an autonomous class between the Clorophyta and the Traqueophyta.<br><b…
The Problem of Existential Import in Metathetic Propositions: Qutb al-Din al-Tahtani contra Fakhr al-Din al-Razi
2019
This paper addresses discussions in post-Avicennan Arabic logic on various characterizations of metathetic propositions and their status vis-à-vis the existential import condition by focusing on the arguments made by Fakhr al-Dīn al-Rāzī (d. 606/1210) and the counter-arguments by Quṭb al-Dīn al-Rāzī al-Taḥtānī (d. 766/1365), both of whom established their positions in a framework drawn by Avicenna (Ibn Sīnā, d. 428/1037), the most prominent figure in the tradition of classical Arabic logic. In his logic texts, Avicenna thoroughly discusses the problem of the existential import in metathetic propositions (ma‘dūla), and seems to have presumed the existential import to be a truth-condition for…
An original experimental approach to study the alteration and/or contamination of archaeological ceramics originated by seawater burial
2014
This paper deals with the proposal of an original experimental methodological approach specifically designed for appraising any compositional alteration and/or contamination of archaeological ceramics after the protracted contact with seawater. A series of ceramic test-pieces (briquettes and cylinders) were purposely manufactured by mixing selected calcareous or non-calcareous clays with different varieties of sieved sand temper. The aim was to reasonably simulate the ceramic pastes most frequently found in the shipwrecks recovered in the coastal areas of western Mediterranean. The used raw materials were previously characterized in terms of mineralogical and chemical composition (XRPD, XRF…
L'exposition photographique de rue. Le rapport à l'œuvre, entre relation et interaction
2009
In the very particular context (press crisis, digital revolution, photojournalism shifting towards art market), photographic exhibitions have been organized in the street, these last years. How does it build the relationship to the creation ? This article shows that this relationship comes into being gradually on the inter subjective relations ; from relationship (subject / object connection), the esthetic experience changes into interaction in the sense of the symbolic interactionism (complex process where intertwines perceptions, interpretations, mutual adaptations between the subjects themselves and between subjects and objects). The study, result of a direct observation, takes place in …
Modélisation de l'exposition au bruit en milieu urbain et études épidémiologiques : quelles sources sonores ?
2009
National audience; Epidemiological studies on noise in urban areas are mostly based on a modelling approach which only focuses on noise sources related to transportation and industries. Additional sources are likely to influence the ambient noise level, but the spatio-temporal influence they could have is rarely studied. The objective of this study is to identify urban noise sources that could improve environmental noise prediction and to quantify their respective contributions. An acoustic measurement campaign was conducted in frontage of 44 dwellings located on the city of Besancon (France). Measurements were compared to noise levels predictions produced from different noise maps in which…