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1.
Physiological and transcriptional responses to saline irrigation of young ‘Tempranillo’ vines grafted onto different rootstocks
Ignacio Buesa, Juan G. Pérez-Pérez, Fernando Visconti, Rebeka Strah, Diego S. Intrigliolo, Luis Bonet, Kristina Gruden, Maruša Pompe Novak, Jose M. de Paz, 2022, izvirni znanstveni članek

Povzetek: The use of more salt stress-tolerant vine rootstocks can be a sustainable strategy for adapting traditional grapevine cultivars to future conditions. However, how the new M1 and M4 rootstocks perform against salinity compared to conventional ones, such as the 1103-Paulsen, had not been previously assessed under real field conditions. Therefore, a field trial was carried out in a young ‘Tempranillo’ (Vitis vinifera L.) vineyard grafted onto all three rootstocks under a semi-arid and hot-summer Mediterranean climate. The vines were irrigated with two kinds of water: a non-saline Control with EC of 0.8 dS m–1 and a Saline treatment with 3.5 dS m–1. Then, various physiological parameters were assessed in the scion, and, additionally, gene expression was studied by high throughput sequencing in leaf and berry tissues. Plant water relations evidenced the osmotic effect of water quality, but not that of the rootstock. Accordingly, leaf-level gas exchange rates were also reduced in all three rootstocks, with M1 inducing significantly lower net photosynthesis rates than 1103-Paulsen. Nevertheless, the expression of groups of genes involved in photosynthesis and amino acid metabolism pathways were not significantly and differentially expressed. The irrigation with saline water significantly increased leaf chloride contents in the scion onto the M-rootstocks, but not onto the 1103P. The limitation for leaf Cl– and Na+ accumulation on the scion was conferred by rootstock. Few processes were differentially regulated in the scion in response to the saline treatment, mainly, in the groups of genes involved in the flavonoids and phenylpropanoids metabolic pathways. However, these transcriptomic effects were not fully reflected in grape phenolic ripeness, with M4 being the only one that did not cause reductions in these compounds in response to salinity, and 1103-Paulsen having the highest overall concentrations. These results suggest that all three rootstocks confer short-term salinity tolerance to the scion. The lower transcriptomic changes and the lower accumulation of potentially phytotoxic ions in the scion grafted onto 1103-Paulsen compared to M-rootstocks point to the former being able to maintain this physiological response in the longer term. Further agronomic trials should be conducted to confirm these effects on vine physiology and transcriptomics in mature vineyards.
Ključne besede: osmotic adjustment, gas exchange, gene expression, water relations, Vitis vinifera L. (grapevine), salinity tolerance
Objavljeno v DiRROS: 17.07.2024; Ogledov: 134; Prenosov: 106
.pdf Celotno besedilo (2,32 MB)
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2.
Phytoplankton assemblage over a 14-year period in the Adriatic Sea : patterns and trends
Sanda Skejić, Blanka Milić Roje, Frano Matić, Jasna Arapov, Janja Francé, Mia Bužančić, Ana Bakrač, Maja Straka, Živana Ninčević Gladan, 2024, izvirni znanstveni članek

Povzetek: Considering the role of phytoplankton in the functioning and health of marine systems, it is important to characterize its responses to a changing environment. The central Adriatic Sea, as a generally oligotrophic area, is a suitable environment to distinguish between regular fluctuations in phytoplankton and those caused by anthropogenic or climatic influences. This study provides a long-term perspective of phytoplankton assemblage in the central eastern Adriatic Sea, with 14 years of continuous time series data collected at two coastal and two offshore stations. The predominant phytoplankton groups were diatoms and phytoflagellates, but their proportion varied depending on the vicinity of the coast, as evidenced also by the distribution of chlorophyll a. In the coastal environment, the phytoplankton biomass was substantially higher, with a higher proportion of microphytoplankton, while small phytoplankton accounted for the majority of biomass in the offshore area. In addition, a decreasing trend in diatom abundance was observed in the coastal waters, while such trend was not so evident in the offshore area. Using a neural gas algorithm, five clusters were defined based on the contribution of the major groups. The observed increase in diversity, especially in dinoflagellates, which outnumber diatom taxa, could be a possible adaptation of dinoflagellates to the increased natural solar radiation in summer and the increased sea surface temperature.
Ključne besede: phytoplankton community, long-term data, diversity, chlorophyll a, neural gas analysis, solar radiation, Adriatic Sea
Objavljeno v DiRROS: 11.07.2024; Ogledov: 161; Prenosov: 149
.pdf Celotno besedilo (2,46 MB)
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3.
Quantitative aspects of ToF-SIMS analysis of metals and alloys in a UHV, O2 and H2 atmosphere
Jernej Ekar, Saša Kos, Janez Kovač, 2024, izvirni znanstveni članek

Povzetek: Although secondary ion mass spectrometry (SIMS) is a versatile method used in the fields of surface analysis, depth profiling and elemental and molecular mapping, it also lacks quantification capabilities. The main reason for this is the matrix effect, which influences the ionization yield of secondary ions with respect to the substrate from which the analyzed compounds originate. There are several approaches to reduce the matrix effect, and gas flooding is one of the easiest methods to apply. In this work, we have investigated the possibilities of the ToF-SIMS method for the quantification of selected metals and alloys containing these metals in different ratios by reducing the matrix effect in the presence of different atmospheres. The measurements were performed in the ultra-high vacuum (UHV) environment, H2 and O2 atmospheres. H2 flooding shows the most significant improvements compared to the UHV analysis, while O2 is also promising but has some limitations. Improvements are most evident for the transition metals Ti, Cr, Fe, Co and Ni employed in our study, while the p-block elements such as Al and Si do not change so extensively. The deviations from the true atomic ratios of selected transition metals in different alloys reach a maximum of only 46 % when analyzed in the H2 atmosphere. In contrast, these values are 66 and 228 % for the O2 atmosphere and UHV environment, respectively. Our results suggest that gas adsorption and consequent formation of a new matrix on the surface, especially in the case of hydrogen, reduces the differences between the different chemical environments and electronic structures of the surface. In this way, the quantitative aspects of the SIMS method can be improved.
Ključne besede: ToF-SIMS quantification, H2 and O2 gas flooding, matrix effect reduction, cluster secondary ions
Objavljeno v DiRROS: 15.05.2024; Ogledov: 263; Prenosov: 203
.pdf Celotno besedilo (1,15 MB)

4.
An experimental study of liquid micro-jets produced with a gas dynamic virtual nozzle under the influence of an electric field
Bor Zupan, Gisel Esperanza Peña-Murillo, Rizwan Zahoor, Jurij Gregorc, Božidar Šarler, Juraj Knoška, Alfonso M. Gañán-Calvo, Henry N. Chapman, Saša Bajt, 2023, izvirni znanstveni članek

Povzetek: The results of an experimental study of micro-jets produced with a gas dynamic virtual nozzle (GDVN) under the influence of an electric field are provided and discussed for the first time. The experimental study is performed with a 50% volume mixture of water and ethanol, and nitrogen focusing gas. The liquid sample and gas Reynolds numbers range from 0.09–5.4 and 0–190, respectively. The external electrode was positioned 400–500 μm downstream of the nozzle tip and an effect of electric potential between the electrode and the sample liquid from 0–7 kV was investigated. The jetting parametric space is examined as a function of operating gas and liquid flow rates, outlet chamber pressure, and an external electric field. The experimentally observed jet diameter, length and velocity ranged from 1–25 μm, 50–500 μm and 0.5–10 m/s, respectively. The jetting shape snapshots were processed automatically using purposely developed computer vision software. The velocity of the jet was calculated from the measured jet diameter and the sample flow rate. It is found that micro-jets accelerate in the direction of the applied electric field in the downstream direction at a constant acceleration as opposed to the standard GDVNs. New jetting modes were observed, where either the focusing gas or the electric forces dominate, encouraging further theoretical and numerical studies towards optimized system design. The study shows the potential to unlock a new generation of low background sample delivery for serial diffraction measurements of weakly scattering objects.
Ključne besede: micro jet, electric field, experimental study, flow focusing, Taylor cone, gas dynamic virtual nozzles
Objavljeno v DiRROS: 07.02.2024; Ogledov: 504; Prenosov: 191
.pdf Celotno besedilo (1,94 MB)
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5.
Warm mix asphalt use in Slovenia and in Europe : a review
Primož Pavšič, 2022, pregledni znanstveni članek

Povzetek: Recently, we have witnessed an extreme increase in the prices of energy and raw materials, on the one hand, and economic expansion, due to the business growth in construction sector, part of which is also the asphalt industry, on the other hand. The asphalt industry in particular is facing increasing challenges of economic acceptability and reducing greenhouse gas emissions, as well as improving working conditions. One of the possible solutions proved to be warm mix asphalts (WMA), which can be produced and compacted at reduced temperatures in comparison to hot mix asphalt (HMA). The beginnings of WMA technology in Europe date back to 1999, while in Slovenia the first field test was conducted in 2005. In the last two decades a numerous research and studies on the properties and technologies of WMA production have been conducted. According to EAPA (European Asphalt Pavement Association), the use of WMA cumulatively in Europe in period from 2013 to 2020 is slowly increasing, but the differences in WMA production in individual European countries are significant. The article presents an overview of WMA production techniques, their advantages and disadvantages and their usage in individual European countries in comparison to Slovenia.
Ključne besede: warm mix asphalt, pavement, environment, greenhouse gas emmissions
Objavljeno v DiRROS: 31.01.2024; Ogledov: 421; Prenosov: 181
.pdf Celotno besedilo (470,00 KB)
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Novel thermal insulation with gas-filled cavities - assessment of thermal performance of different designs based on numerical simulations of heat transfer
Miha Jukić, Sabina Jordan, Danijel Lisičić, 2019, izvirni znanstveni članek

Povzetek: Not only is the energy efficiency of buildings nowadays becoming more and more important; the legislative requirements, the people’s awareness of the environmental questions and their thermal comfort expectations are also on a much higher level. All of these issues can be addressed by making the building envelope more thermally resistant. However, with the traditional thermal insulation materials the thickness of thermal insulation layers is already at the viable limits. Therefore, the development of new, more efficient thermal insulation products with a higher thermal resistance is highly promoted. Preliminary research results can be applied to models to develop and confirm the conceptual designs of such new materials. In this paper, an analysis of thermal performance is presented for a novel thermal insulation consisting of graphite polystyrene (GPS) matrix with cavities filled with an insulative gas, and a protective sheath to prevent it from leaking. Bearing in mind the suitability for later production, different configurations of the assembly were considered, regarding the matrix geometry, the type of the gas filling, and the surface emissivity of the cavities. A range of numerical simulations of heat transfer was conducted to determine the efficiency of different designs in reducing the conductive, the convective, and the radiative heat transfer. Advantages, limitations and some detailed parameters of the proposed design concepts were determined, which were then used for optimisation. The analysis of the results indicates that the equivalent thermal conductance of a GPS panel can be significantly reduced by the introduction of gas-filled cavities. The reduction is highly dependent on the type of the gas filling (thermal conductivity, viscosity, specific heat, etc.), the size of the cavities, and the cavity surface emissivity.
Ključne besede: gas-filled cavities, graphite polystyrene, numerical simulation, thermal insulation
Objavljeno v DiRROS: 15.09.2023; Ogledov: 437; Prenosov: 213
.pdf Celotno besedilo (1,21 MB)
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9.
Carbon isotopic composition of methane and its origin in natural gas from the Petišovci-Dolina oil and gas field (Pannonian Basin System, NE Slovenia) – a preliminary study
Miloš Markič, Tjaša Kanduč, 2022, izvirni znanstveni članek

Povzetek: The carbon isotopic composition of methane (δ13CCH4) in natural gas from the Petišovci-Dolina oil and gas field (NE Slovenia) was measured for the first time in August and September 2021. The gas samples from different depths were taken from three wells: Dolina-deep (Pg-6) from the depth interval 3102–3104 m, Petišovci-deep (Pg-5) from the depth interval 2772–2795 m, and Petišovci-shallow (D-5) from the depth interval 1212–1250 m. According to the available composition dataset of gas, available from the Petrol Geo d.o.o. documentation, the “deep” gases sampled from the Pg-6 and Pg-5 wells consist of 85 % methane (C1), 11 % hydrocarbons heavier than methane (C2–C6) and 4 % CO2. The “shallow” gas from well D-5 contains more than 89 % methane, up to 11 % C2–C6 gases, while the CO2 content is negligible. The “deep« gas from the Pg-6 and Pg-5 wells has δ13CCH4 -36.7 ‰ and -36.6 ‰, respectively, while the “shallow” gas from the D-5 well has the δ13CCH4 of -38.6 ‰. The methane from the “shallow” gas is slightly enriched in the lighter 12C isotope. δ13CCH4 in the range from -38.6 to -36.6 ‰ clearly indicates the thermogenic origin of methane formed during the catagenesis phase of gas formation.
Ključne besede: Petišovci-Dolina, gas, methane, isotopes, origin
Objavljeno v DiRROS: 26.07.2022; Ogledov: 1274; Prenosov: 297
.pdf Celotno besedilo (724,51 KB)

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