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3612. On spin description of water-biopolymer interactions: theory and experiment of reentrant order-disorder transition.Artem Badasyan, predavanje na tuji univerzi Opis: The experimental studies of biopolymer conformations have reached an unprecedented level of
detailization during the past decade and allow now to study single molecules in vivo [1]. Processing of
experimental data essentially relies on theoretical approaches to conformational transitions in
biopolymers [2]. However, the models that are currently used, originate from the early 1960's and
contain several unjustified assumptions, widely accepted at that time. Thus, the view on the
conformational transitions in the polypeptides as a two-state process has very limited applicability
because the all-or-none transition mechanism takes place only in short polypeptides with sizes
comparable to the spatial correlation length; the original formulation of Zimm-Bragg model is
phenomenological and does not allow for a microscopic model for water; the implicit consideration of
the water-polypeptide interactions through the ansatz about the quadratic dependence of free energy
difference on temperature can only be justified through the assumption of an ideal gas with a constant
heat capacity. To get rid of these deficiencies, we augment the Hamiltonian formulation [3] of the
Zimm-Bragg model [4] with the term describing the water-polypeptide interactions [5]. The analytical
solution of the model results in a formula, ready to be fit to Circular Dichroism (CD) data for both heat
and cold denaturation. On the example of several sets of experimental data we show, that our formula
results in a significantly better fit, as compared to the existing approaches. Moreover, the application
of our procedure allows to compare the strengths of inter- and intra-molecular H-bonds, an
information, inaccessible before.
Ključne besede: helix-coil transition, water-polypeptide interactions
Objavljeno v RUNG: 13.03.2019; Ogledov: 3182; Prenosov: 0
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3613. |
3614. |
3615. Pogovor o zborniku Goriški izobraženci skozi zgodovinoŽeljko Oset, druga izvedena dela Ključne besede: Univerza v Novi Gorici, Mestna občina Nova Gorica, izobraženci, znanost, kultura, Gorica, Marija Perpar, Anton Brecelj, Valentin Stanič, Franjo Rojec, goriška judovska skupnost, Bodumil Vošnjak, goriški zgodovinarji, Miha Zega, Pavlina Pajk
Objavljeno v RUNG: 08.03.2019; Ogledov: 3491; Prenosov: 0
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3616. Investigation of Aerosol Properties and Structures in Two Representative Meteorological Situations over the Vipava Valley Using Polarization Raman LiDARLonglong Wang, Samo Stanič, William Eichinger, Griša Močnik, Luka Drinovec, Asta Gregorič, 2019, izvirni znanstveni članek Opis: Vipava valley in Slovenia is a representative hot-spot for complex mixtures of different aerosol types of both anthropogenic and natural origin. Aerosol loading distributions and optical properties were investigated using a two-wavelength polarization Raman LiDAR, which provided extinction coefficient, backscatter coefficient, depolarization ratio, backscatter Ångström exponent and LiDAR ratio profiles. Two different representative meteorological situations were investigated to explore the possibility of identifying aerosol types present in the valley. In the first case, we investigated the effect of strong downslope (Bora) wind on aerosol structures and characteristics. In addition to observing Kelvin–Helmholtz instability above the valley, at the height of the adjacent mountain ridge, we found new evidence for Bora-induced processes which inject soil dust aerosols into the free troposphere up to twice the height of the planetary boundary layer (PBL). In the second case, we investigated aerosol properties and distributions in stable weather conditions. From the observed stratified vertical aerosol structure and specific optical properties of different layers we identified predominant aerosol types in these layers.
Ključne besede: aerosol structures, aerosol characterization, polarization Raman LiDAR, Vipava valley
Objavljeno v RUNG: 08.03.2019; Ogledov: 3890; Prenosov: 118
 Celotno besedilo (3,11 MB) |
3617. Self-cleaning and photoactive TiO2 – ZrO2 – SiO2 films on thermosensitive and glass substratesNives Vodišek, Urška Lavrenčič Štangar, 2017, objavljeni povzetek znanstvenega prispevka na konferenci Opis: Nanosized TiO2 is well-known for its photocatalytic property. From the combination of photocatalysis and photoinduced hydrophilicity properties, thin films of this material have also anti-fogging, self-cleaning and antimicrobial properties. There are numerous deposition techniques e.g. spin-coating, dip-coating, spraying, the most suitable one is chosen based on substrate or solution characteristics. Thin films are often required to be transparent for visible light, especially if we use them on transparent substrates, or they should not affect the color of the substrate. Radicals that are produced during photosensitizing process are able to destroy structure of a substrate and substrate can lose mechanical stability [1,2]. Some studies show that adding a SiO2 protective layer can prevent the damage of the substrate [3–5]. Ti-Zr containing sols were prepared with sol-gel process, where titanium(IV) isopropoxide, zirconium(IV) butoxide and ethanol were hydrolyzed with aqueous solution of perchloric acid. Solution was then refluxed for 48 hours. During that time crystallization and deaggregation took place and that resulted in a stable final solution [6]. To prepare suitable solution for production of durable films silica binder was added. On glass and plastic substrates, thin films were deposited with the dip-coating method and dried with a heat-gun. Thin films were characterized by measurements of photocatalytic activity with terephthalic acid as model organic pollutant subjected to oxidation via fluorescent degradation product, photoinduced superhydrophilicity phenomena, UV-Vis and ATR-FTIR spectroscopy, SEM images, as well as mechanical properties measurements.
References
[1] H. Schmidt, M. Naumann, T.S. Müller, M. Akarsu, Thin Solid Films (2006) 502, 132– 137.
[2] W. A. Daoud, J.H. Xin, Y.H. Zhang, Surf. Sci. (2005) 599, 69–75.
[3] Ž. Senić, S. Bauk, M. Vitorović-Todorović, N. Pajić, A. Samolov, D. Rajić, Sci. Tech. Rev. (2011) 61, 63–72.
[4] T. Yuranova, R. Mosteo, J. Bandara, D. Laub, J. Kiwi, J. Mol. Catal. A: Chem. (2006) 244, 160–167.
[5] T. Yuranova, D. Laub, J. Kiwi, Catal. Today (2007) 122, 109–117.
[6] N. Vodišek, K. Ramanujachary, V. Brezová, U. Lavrenčič Štangar, Catal. Today (2017) 287, 142–147.
Ključne besede: Self-cleaning surface, photocatalysis, TiO2, ZrO2, SiO2, PVC, PMMA, thermosensitive substrates, glass
Objavljeno v RUNG: 05.03.2019; Ogledov: 3683; Prenosov: 0
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3618. Sadovnjak Pod skalco: goriško sadje iz preteklosti v prihodnostZoran Božič, druga izvedena dela Opis: Prezentacija prinaša oris razvoja sadjarstva na Goriškem od druge polovice 19. stoletja do danes, predstavitev prednosti ekološkega sadjarstva in prikaz značilnosti sadovnjaka Pod skalco v Brdih.
Ključne besede: Goriška, visokodebelni sadovnjak, ekološka pridelava, sadjarstvo, Brda, Ivan Bolle, Rihard Dolenc, Evgen Klavžar, Josip Rustja, Just Ušaj, Martin Humek, Franc Vuga, Morsko, Sveti Križ, stare sadne sorte
Objavljeno v RUNG: 04.03.2019; Ogledov: 3520; Prenosov: 0
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