4621. Edge profiles in K shell photoabsorption spectra of gaseous hydrides of 3p elements and homologuesRobert Hauko, Jana Padežnik Gomilšek, Alojz Kodre, Iztok Arčon, Giuliana Aquilanti, izvirni znanstveni članek Opis: Photoabsorption spectra of gaseous hydrides of 3p elements (PH3, H2S, HCl) are measured in the energy region of
photoexcitations pertaining to K edge. The analysis of the edge profile is extended to hydrides of 4p series (GeH4,
AsH3, H2Se, HBr) from an earlier experiment, and to published spectra of 2p hydrides (CH4, NH3, H2O, HF) and
noble gases Ar, Kr and Ne and SiH4. The edge profiles are modelled with a linear combination of lorentzian
components, describing excitations to individual bound states and to continuum. Transition energies and
probabilities are also calculated in the non-relativistic molecular model of the ORCA code, in good agreement
with the experiment. Edge profiles in the heavier homologues are closely similar, the symmetry of the molecule
governs the transitions to the lowest unoccupied orbitals. In 2p series the effect of the strong nuclear potential
prevails. Transitions to higher, atomic-like levels remain very much the same as in free atoms. Ključne besede: X-ray absorption spectra, gaseous hydrides, 3p K-edge spectra, DFT Objavljeno v RUNG: 23.08.2017; Ogledov: 3622; Prenosov: 0 Gradivo ima več datotek! Več... |
4622. Electrochemical dissolution of iridium and iridium oxide particles in acidic media : transmission electron microscopy, electrochemical flow cell coupled to inductively coupled plasma mass spectrometry and X-ray absorption spectroscopy studyPrimož Jovanovič, Nejc Hodnik, Francisco Ruiz-Zepeda, Iztok Arčon, Barbara Jozinović, Milena Zorko, Marjan Bele, Martin Šala, Vid Simon Šelih, Samo B. Hočevar, Miran Gaberšček, 2017, izvirni znanstveni članek Opis: Iridium based particles as the most promising proton exchange membrane electrolyser electrocatalysts were investigated
by transmission electron microscopy (TEM), and by coupling of electrochemical flow cell (EFC) with online inductively
coupled plasma mass spectrometer (ICP-MS). Additionally, a thin-film rotating disc electrode (RDE), an identical location transmission
and scanning electron microscopy (IL-TEM and IL-SEM) as well as an X-ray absorption spectroscopy (XAS) studies have
been performed. Extremely sensitive online time-and potential-resolved electrochemical dissolution profiles revealed that iridium
particles dissolved already well below oxygen evolution reaction (OER) potentials, presumably induced by iridium surface oxidation
and reduction processes, also referred to as transient dissolution. Overall, thermally prepared rutile type IrO2 particles (T-IrO2)
are substantially more stable and less active in comparison to as prepared metallic (A-Ir) and electrochemically pretreated (E-Ir)
analogues. Interestingly, under OER relevant conditions E-Ir particles exhibit superior stability and activity owing to the altered
corrosion mechanism where the formation of unstable Ir(>IV) species is hindered. Due to the enhanced and lasting OER performance,
electrochemically pre-oxidized E-Ir particles may be considered as the electrocatalyst of choice for an improved low temperature
electrochemical hydrogen production device, namely a proton exchange membrane electrolyser. Ključne besede: Iridium Oxide Par-ticles, Electrochemical Dissolution of Iridium, Ir L3-edge XANES Objavljeno v RUNG: 23.08.2017; Ogledov: 3832; Prenosov: 0 Gradivo ima več datotek! Več... |
4623. DEHYDROEPIANDROSTERONE SULFATE CLAWS CONCENTRATIONS IN DOGS FROM BIRTH TO 30 DAYS OF AGE: PRELIMINARY RESULTS.Jasmine Fusi, Marta Montillo, Barbara Bolis, Alessandro Rota, Tanja Peric, Maria Cristina Veronesi, 2017, objavljeni povzetek znanstvenega prispevka na konferenci Opis: Similarly to all other species, also in the dog improvements in the knowledge on perinatology are mandatory for a better management of newborns, mainly aimed to reduce the impact of perinatal mortality. However, until recently, the study of canine perinatology was limited mainly because of the invasiveness of many investigation procedures, such as repeated blood sampling. In recent times, the claws/nails were proved to be a useful, non invasive, matrix for long time-frame retrospective hormone concentrations analysis also in babies and puppies [1,2], providing a suitable matrix for perinatal long-term hormonal changes studies. The last intrauterine foetal stage of development and the neonatal period represent the most challenging phases for the mammals offspring. It was demonstrated that the activation of the fetal hypothalamic-pituitary-adrenal (HPA) axis leads to dehydroepiandrosterone (DHEA) and DHEA sulfate (DHEA-S) secretion, the major fetal steroids. Thus, DHEA-S measured at birth in newborns could be considered as a marker of offspring HPA axis activity, under the maternal influence. This study was aimed to assess the DHEA-S concentrations in newborn puppies claws, collected at birth and at 30 days of age, and to evaluate the possible influence of age, gender and type of birth on DHEA-S claws accumulation. The study was performed on 58 large purebred, normal, healthy, viable (Apgar≥7) puppies, 31 males and 27 females, born by vaginal spontaneous (N=22) or caesarean (N=36) parturition. DHEA-S was analysed by RIA. The mean ± SD DHEA-S claws concentration significantly (p<0.01) decreased from birth (210±152.00 pg/mg) to 30 days (91±72.63 pg/mg), evidencing the higher fetal DHEA-S secretion in the last fetal stage of pregnancy in comparison to the first postnatal month of age. According to the type of parturition, higher (p<0.001) DHEA-S claws concentrations were found at birth in puppies born by spontaneous than caesarean parturition (300±167.05 vs 154±112.23 pg/mg, respectively); this finding deserves further investigations. No influence of newborn gender was found. Claws DHEA-S values at birth were a bit higher, but with a lower SD, in comparison to data reported for babies 1-3 weeks old [1]. The trend of decrease is in agreement with data reported for cortisol [2] in dead puppies, and suggests, beside the role of cortisol, the important effects of DHEA-S around the time of birth, also in puppies, as reported for babies [1].
[1] Tegethoff et al. Dehydroepindrosterone in nails of infants: a potential biomarker of intrauterine responses to maternal stress. Biological psychology, 87: 414-420, 2011. [2] Veronesi et al. Coat and claws as new matrices for noninvasive long-term cortisol assessment in dogs from birth up to 30 days of age. Theriogenology, 84: 791-796, 2015. Ključne besede: DHEA-S, claw, dog Objavljeno v RUNG: 22.08.2017; Ogledov: 4145; Prenosov: 0 Gradivo ima več datotek! Več... |
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4625. Der Bruch mit der literarischen Tradition: Weibliche Identitätskonzepte in Zofka Kveders multikulturellem ŒuvreKatja Mihurko, 2016, izvirni znanstveni članek Opis: This article presents the literary opus of the writer Zofka KVEDER (1878-1926). She was active in various cultural environments, such as Trieste, Bern, Prague, and Zagreb, and she published works in Slovenian, German, Czech, and Croatian. What is special about her opus is the clear feminist engagement. The centre of her works is female characters and their search for identity. The writer puts them in the roles of the new women: artists, intellectuals, travellers, and wanderers around Europeans capitals. They are also often depicted in various, unconventional maternal roles. Her protagonists belong to all social classes. In the depictions of the social hardship of proletarians, modern stylistic devices make way for unadorned naturalist depictions of reality. The author’s texts, from the numerous short stories to the novels Njeno življenje [Her Life] and Hanka, are an interesting dialogue with the works of her contemporaries from other national literatures, mainly German, Austrian, Czech and Croatian. They are an important contribution for both modern culture as well as the development of female authorship. Ključne besede: Zofka Kveder, Mutterbilder, New Woman, Laura Marholm, Misterij žene, Hanka Objavljeno v RUNG: 22.08.2017; Ogledov: 3573; Prenosov: 0 Gradivo ima več datotek! Več... |
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4627. Spol v dobi moderne : Učno gradivo za predmet Spol v dobi moderneKatja Mihurko, drugo učno gradivo Ključne besede: Christine de Pizan, Rosa Mayreder, Ellen Key, Otto Weininger, Sigmund Freud, Marica Nadlišek, Elvira Dolinar, Zofka Kveder, Alma Karlin, seksizem Objavljeno v RUNG: 22.08.2017; Ogledov: 4448; Prenosov: 0 Gradivo ima več datotek! Več... |
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4630. Biogas production from brewery spent grain as a mono-substrate in a two-stage process composed of solid-state anaerobic digestion and granular biomass reactorsMario Panjicko, Gregor Drago Zupančič, Romana Marinšek-Logar, Lijana Fanedl, Marina Tišma, Bruno Zelić, 2017, izvirni znanstveni članek Opis: Anaerobic digestion of brewery spent grain as a mono-substrate was studied. Brewery spent grain is a substrate consisting largely of cellulose, hemicellulose and lignin, which are difficult to degrade anaerobically, mostly due to the presence of degradation products, such as phenolic compounds, which cause process inhibition. Therefore, a two-stage system was used for anaerobic digestion. Anaerobic digestion was phase separated in a solid-state anaerobic digestion reactor, where microbiological hydrolysis and acidogenesis occurred and in a granular biomass reactor where mostly methanogenesis was performed. The overall process exhibited total solids degradation efficiency between 75.9 and 83.0 %. Average specific biogas production was 414±32 L/kg, whereas biomethane production was 224±34 L/kg of added total solids. Granular biomass after adaptation exhibited stable operation at substrate C/N ratios in range 0.16 – 4.68. p-cresol was present in concentrations up to 45 mg/L and during the process was successfully degraded by granular biomass. The excellent adaptability of granular biomass was confirmed by 68.2 % shift in bacterial and a 31.8 % shift in archaeal community structure in a granular biomass reactor. The structure of the bacterial community from granular biomass reactor and solid-state anaerobic digestion reactor remained 79.4 % similar at the end of the experiment, whereas archaeal community was only 31.6 % similar. The process exhibited stable operation for 198 days, which shows that brewery spent grain can be successfully anaerobically digested and used for biogas production. Ključne besede: biogas production, brewery spent grain, C/N ratio, dry digestion, microbial biomass, solid-state anaerobic digestion Objavljeno v RUNG: 18.08.2017; Ogledov: 4290; Prenosov: 0 Gradivo ima več datotek! Več... |