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11.
Retrieval of Vertical Mass Concentration Distributions—Vipava Valley Case Study
Longlong Wang, Samo Stanič, Klemen Bergant, William Eichinger, Griša Močnik, Luka Drinovec, Janja Vaupotič, Miloš Miler, Mateja Gosar, Asta Gregorič, 2019, original scientific article

Abstract: Aerosol vertical profiles are valuable inputs for the evaluation of aerosol transport models, in order to improve the understanding of aerosol pollution ventilation processes which drive the dispersion of pollutants in mountainous regions. With the aim of providing high-accuracy vertical distributions of particle mass concentration for the study of aerosol dispersion in small-scale valleys, vertical profiles of aerosol mass concentration for aerosols from different sources (including Saharan dust and local biomass burning events) were investigated over the Vipava valley, Slovenia, a representative hot-spot for complex mixtures of different aerosol types of both anthropogenic and natural origin. The analysis was based on datasets taken between 1–30 April 2016. In-situ measurements of aerosol size, absorption, and mass concentration were combined with lidar remote sensing, where vertical profiles of aerosol concentration were retrieved. Aerosol samples were characterized by SEM-EDX, to obtain aerosol morphology and chemical composition. Two cases with expected dominant presence of different specific aerosol types (mineral dust and biomass-burning aerosols) show significantly different aerosol properties and distributions within the valley. In the mineral dust case, we observed a decrease of the elevated aerosol layer height and subsequent spreading of mineral dust within the valley, while in the biomass-burning case we observed the lifting of aerosols above the planetary boundary layer (PBL). All uncertainties of size and assumed optical properties, combined, amount to the total uncertainty of aerosol mass concentrations below 30% within the valley. We have also identified the most indicative in-situ parameters for identification of aerosol type.
Keywords: valley air pollution, aerosol vertical distributions, lidar remote sensing, in-situ measurements, aerosol identification
Published in RUNG: 09.01.2019; Views: 4107; Downloads: 113
.pdf Full text (7,43 MB)

12.
STUDY OF ATMOSPHERIC AEROSOL PROPERTIES IN THE VIPAVA VALLEY
Longlong Wang, doctoral dissertation

Abstract: The aim of the dissertation was to study aerosol loading distributions and properties over the Vipava valley, a representative hot-spot for complex mixtures of different aerosol types of both anthropogenic and natural origin. An infrared Mie and a two-wavelength polarization Raman lidar systems were used as main detection tools. The polarization Raman lidar, which provides the capability to extract the extinction coefficient, backscatter coefficients, depolarization ratio, backscatter Ångström exponent, lidar ratio and water vapor mixing ratio profiles, was itself designed, built and calibrated as a part of this thesis. Lidar data, combined with in-situ measurements, was used to determine detailed information on different aerosol types. Vertical profiles of aerosol mass concentration were extracted from the Mie lidar data taken in April 2016, where the in-situ measurements of aerosol size distribution and number concentration as well as aerosol absorption coefficient and black carbon mass concentration were used to estimate the mass extinction efficiency (MEE). Aerosol morphology and chemical composition determined by SEM-EDX on sampled particles were used for the identification of primary aerosol types. Two cases with different atmospheric conditions (long range mineral dust transport and local biomass burning) and different expected the dominant presence of specific aerosol types (mineral dust and soot) were investigated in more detail. They revealed significantly different aerosol properties and distributions within the valley, affecting radiative heat exchange. A more detailed investigation of aerosol properties throughout the troposphere in different atmospheric conditions was made possible by the two-wavelength polarization Raman lidar system, deployed in Ajdovščina (town of Vipava valley) from September 2017. Using its aerosol identification capabilities, based on particle depolarization ratio and lidar ratio measurements, it was possible to identify predominant aerosol types in the observed atmospheric structures, for example in different atmospheric layers in the case of the stratified atmosphere. Primary anthropogenic aerosols within the valley were found to be mainly emitted from two sources: individual domestic heating systems, which mostly use biomass fuel and traffic. Natural aerosols, transported over large distances, such as mineral dust and sea salt, were observed both above and entering into the planetary boundary layer. Backscatter contribution of each aerosol type was separated and the corresponding extinction contribution was derived from lidar observations.
Keywords: Vipava valley, aerosol distribution, aerosol characterization, lidar remote sensing, in-situ measurements, aerosol loading.
Published in RUNG: 23.10.2018; Views: 7223; Downloads: 157
.pdf Full text (29,39 MB)

13.
When a wh refuses to stay in-situ
Ali Al Moussaoui, Arthur Stepanov, unpublished invited conference lecture

Keywords: Arabic, wh-movement, syntax, wh-in-situ
Published in RUNG: 07.02.2018; Views: 3371; Downloads: 0
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14.
Advances and Achievements in In Situ Analysis of Corrosion and Structure– Property Relationship in Mg Alloys
Dmytro Orlov, Vineet Joshi, 2016, preface, editorial, afterword

Keywords: magnesium alloys, in-situ
Published in RUNG: 20.02.2017; Views: 4257; Downloads: 0
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15.
Atomically resolved dealloying of structurally ordered Pt nanoalloy as an oxygen reduction reaction electrocatalyst
Andraž Pavlišič, Primož Jovanovič, Vid Simon Šelih, Martin Šala, Marjan Bele, Goran Dražić, Iztok Arčon, Samo B. Hočevar, Anton Kokalj, Nejc Hodnik, Miran Gaberšček, original scientific article

Abstract: The positive effect of intermetallic ordering of platinum alloy nanoparticles on oxygen reduction reaction (ORR) activity has been well established. What is still missing is an understanding of selective leaching of the less noble metal from the ordered structure and its correlation to longterm ORR performance. Using a combination of kinetic Monte Carlo simulations and advanced characterization techniques, we provide unprecedented insight into dealloying of intermetallic PtCu3 nanoparticles a well-known binary alloy. Comparison of ordered and disordered samples with identical initial compositions and particle size distributions reveals an unexpected correlation: whereas the copper dealloying rates in the ordered and disordered counterparts are almost the same, in the ordered structure Pt atoms are surrounded by 15−30% more Cu atoms throughout all the stages of acid leaching. This more convenient Pt−Cu coordination explains the statistically significant increase of 23−37% in ORR activity of the ordered structure at all stages of alloy degradation.
Keywords: ORR activity, fuel cells, platinum alloy, nanoparticle stability, intermetallic ordering, kinetic Monte Carlo, dealloying, in situ ICP-MS
Published in RUNG: 27.09.2016; Views: 5528; Downloads: 0
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16.
On the Optionality of Wh-Fronting in a Multiple Wh-Fronting Language
Petra Mišmaš, 2015, doctoral dissertation

Abstract: This thesis explores the fact that in Slovenian multiple wh-questions not all wh-phrases have to front. This suggests that multiple wh-movement in Slovenian is optional. The majority of the existing literature on multiple wh-fronting focuses on questions in which all wh-phrases have to move to clause initial positions, I, on the other hand, focus on optionality in multiple wh-questions. I show movement in Slovenian is not avoided because of phonological, syntactic or semantic restrictions that influence other languages (cf. Bošković 2002), and that the Principle of Distinctness (Richards 2010) does not account for all cases of optional multiple wh-fronting in Slovenian. Three types of multiple wh-questions in Slovenian are determined and analyzed: (i) questions in which all wh-phrases move to clause initial positions (i.e. questions with multiple wh-fronting), (ii) questions in which one wh-phrase has to be moved to a clause initial position and the rest undergo movement to a clause internal position (multiple wh-questions with short movement), (iii) questions in which at least one wh-phrase has to be moved to a clause initial position and the rest stay in situ (multiple wh-questions with wh-in-situ). Crucially, in all three types at least one wh-phrase has to move to a clause initial position for a question to receive a true question reading. I assume the Cartographic approach and propose an account of multiple wh-fronting in Slovenian in which one wh-phrase has to move to an Interrogative Projection (the clause initial position) in the Left Periphery while the remaining wh-phrases move to Wh-Projections in the Left Periphery, questions in (i), or the Low Periphery, questions in (ii). I propose that wh-phrases with a wh-feature undergo wh-movement, which means that wh-movement is in fact obligatory in Slovenian. In questions of type (iii), wh-phrases that do not undergo movement are in fact bare wh-pronouns, which one also finds in polarity contexts, that are licensed by the interpretable Q+wh-feature located in the Interrogative Projection. Because the bare wh-pronouns do not come with a wh-feature, they do not have to move. I conclude that wh-movement in Slovenian only appears to be optional.
Keywords: multiple wh-fronting, short movement, optionality, Interrogative Projection, Left Periphery, Low Periphery, bare wh-pronouns, wh-in-situ
Published in RUNG: 10.11.2015; Views: 7942; Downloads: 406
.pdf Full text (1,43 MB)

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