1. Comparative evaluation of corrosion resistance of AISI 316L and Ti6Al4V dental materials under simulated inflammatory conditionsMojca Slemnik, 2025, izvirni znanstveni članek Opis: Titanium and its alloys, as well as stainless steel, are commonly used materials for implants in the human body due to their excellent biocompatibility, corrosion resistance, and mechanical properties. However, the long-term performance of these materials in the oral cavity can be affected by the complex oral environment, including the ingestion of food, beverages, and oral hygiene products, leading to the presence of various ions, pH fluctuations, and inflammatory processes. In this study, the corrosion properties of two biocompatible materials, Ti6Al4V and AISI 316L stainless steel, are investigated under varying oral inflammatory conditions. Using potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), SEM, and EDS analysis, the corrosion behaviour of both materials was analysed in environments simulating mild and severe inflammation. Results indicate that Ti6Al4V exhibits superior corrosion resistance at low H2O2 concentrations mimicking mild inflammation, with significantly lower corrosion rates compared to AISI 316L. However, at higher H2O2 concentrations, which correspond to severe inflammation, AISI 316L shows better resistance despite its susceptibility to pitting corrosion. Both alloys show reduced passivation after 72 h, with corrosion products accumulating on the surface after 96 h, contributing to repassivation. These results emphasise the need for individualized material selection in dental applications based on a patient’s susceptibility to oral inflammation. Ključne besede: corrosion, EIS, inflammatory conditions, titanium, stainless steel, dental materials Objavljeno v DKUM: 19.05.2025; Ogledov: 0; Prenosov: 0
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2. The application of zeolites for fixation of Cr(VI) ions in sedimentsMarjana Simonič, 2025, izvirni znanstveni članek Opis: The aim of the study was to investigate the fixation of Cr(VI) ions from contaminated sediments using synthetic zeolite 4A and natural zeolite clinoptilolite. Parameters such as pH, contact time, adsorption mass and temperature were investigated. If the ions of the heavy metals were mobile, they would become toxic to the environment. After sediment digestion, the initial and final concentrations of Cr(VI) were measured in sediment samples with or without zeolite. Inductively coupled plasma with optical emission spectroscopy (ICP-OES) and X-ray diffraction (XRD) were used to characterize the material. The adsorption kinetics were investigated using a pseudo-first order model, a pseudo-second order model, and an intra-particle diffusion model. The results showed that the zeolites enhanced the fixation of Cr(VI). Chemisorption was the main mechanism when using acid-modified zeolite. Ključne besede: sediment, fixation, heavy metals Objavljeno v DKUM: 19.05.2025; Ogledov: 0; Prenosov: 0
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3. Artificial biomimetic electrochemical assembliesTanja Zidarič, Matjaž Finšgar, Uroš Maver, Tina Maver, 2022, pregledni znanstveni članek Opis: Rapid, selective, and cost-effective detection and determination of clinically relevant
biomolecule analytes for a better understanding of biological and physiological functions are becoming increasingly prominent. In this regard, biosensors represent a powerful tool to meet these
requirements. Recent decades have seen biosensors gaining popularity due to their ability to design
sensor platforms that are selective to determine target analytes. Naturally generated receptor units
have a high affinity for their targets, which provides the selectivity of a device. However, such
receptors are subject to instability under harsh environmental conditions and have consequently low
durability. By applying principles of supramolecular chemistry, molecularly imprinted polymers
(MIPs) can successfully replace natural receptors to circumvent these shortcomings. This review summarizes the recent achievements and analytical applications of electrosynthesized MIPs, in particular,
for the detection of protein-based biomarkers. The scope of this review also includes the background
behind electrochemical readouts and the origin of the gate effect in MIP-based biosensors. Ključne besede: MIP-based biosensors, MIP, biosensors, molecularly imprinted polymer, biomolecules, electroanalysis Objavljeno v DKUM: 15.05.2025; Ogledov: 0; Prenosov: 0
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4. Recent progress in non-enzymatic electroanalytical detection of pesticides based on the use of functional nanomaterials as electrode modifiersTanja Vrabelj, Matjaž Finšgar, 2022, pregledni znanstveni članek Opis: This review presents recent advances in the non-enzymatic electrochemical detection and
quantification of pesticides, focusing on the use of nanomaterial-based electrode modifiers and their
corresponding analytical response. The use of bare glassy carbon electrodes, carbon paste electrodes,
screen-printed electrodes, and other electrodes in this research area is presented. The sensors were
modified with single nanomaterials, a binary composite, or triple and multiple nanocomposites
applied to the electrodes’ surfaces using various application techniques. Regardless of the type
of electrode used and the class of pesticides analysed, carbon-based nanomaterials, metal, and
metal oxide nanoparticles are investigated mainly for electrochemical analysis because they have
a high surface-to-volume ratio and, thus, a large effective area, high conductivity, and (electro)-
chemical stability. This work demonstrates the progress made in recent years in the non-enzymatic
electrochemical analysis of pesticides. The need for simultaneous detection of multiple pesticides
with high sensitivity, low limit of detection, high precision, and high accuracy remains a challenge in
analytical chemistry.
Ključne besede: electroanalysis, non-enzymatic sensors, nanomaterials, pesticides Objavljeno v DKUM: 15.05.2025; Ogledov: 0; Prenosov: 0
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5. The effect of preconditioning strategies on the adsorption of model proteins onto screen-printed carbon electrodesTea Romih, Ivan Konjević, Lea Žibret, Ika Fazarinc, Ajda Beltram, David Majer, Matjaž Finšgar, Samo B. Hočevar, 2022, izvirni znanstveni članek Opis: The preconditioning and modification of the supporting electrode surface is an essential
step in every biosensor architecture. In particular, when using screen-printed carbon electrodes (SPEs)
as inexpensive and convenient disposable sensor substrates, their somewhat lower electrochemical
(surface) reproducibility might represent a complex hurdle. Herein, we investigated the effect of
selected preconditioning strategies, such as cyclic voltammetric pretreatment, in H2SO4 and H2O2
and plasma pretreatment with a positive and negative glow discharge, which all improved the electrochemical stability of the unmodified SPEs. Furthermore, we studied the influence of preconditioning
strategies on the adsorption kinetics of the two most commonly used building blocks for biosensor
preparation, i.e., bovine serum albumin (BSA) and protein A. We observed an advantageous effect
of all the examined preconditioning strategies for the modification of SPEs with protein A, being
the most effective the negative glow discharge. On the other hand, BSA exhibited a more complex
adsorption behavior, with the negative glow discharge as the only generally beneficial preconditioning strategy providing the highest electrochemical stability. Protein A revealed a more substantial
impact on the electrochemical signal attenuation than BSA considering their same concentrations in
the modification solutions. For both BSA and protein A, we showed that the concentrations of 5 and
10 µg mL−1 already suffice for an electrochemically satisfactorily stable electrode surface after 60 min
of incubation time, except for BSA at the positive-plasma-treated electrode. Ključne besede: screen-printed carbon electrode, SPE, electrochemical biosensor, adsorption, bovine serum albumin, protein A, glow discharge Objavljeno v DKUM: 15.05.2025; Ogledov: 0; Prenosov: 0
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6. Improving electricity generation during the product reaction loop and the use of exhaust gas for co-product production using polyethylene waste and flue gas or woodAnita Kovač Kralj, 2022, izvirni znanstveni članek Opis: More energy-efficient industries could reduce the problems of pollution, global warming,
energy security, and fossil fuel depletion, including processing waste into raw materials and more
efficient energy cogeneration. This research project considers the novelties of the upgraded electricity
cogeneration technique, including one open gas turbine during the high-pressure product reaction
loop and a second turbine during the exhaust gas for co-product production with only one compressor.
The upgraded electricity cogeneration was carried out in two steps and based on the productive use of
otherwise useless polyethylene waste, flue gas, and wood. The first step can simulate the simulation
model from the existing product production with well-known technology and process units using
the Aspen Plus® simulator. The maximum available electricity cogeneration can previously be
determined from the thermodynamics of the products and co-products, and an existing energy unit’s
characteristic capacity. In the second step, conventional natural gas can be replaced with waste
as the raw materials by using the same simulated model from the first step, including electricity
cogeneration using the gas turbines during the high-pressure reaction loop, and the exhaust gas as the
co-product with only one compressor. This research on electricity generation is based on processes
that include the pressure drop during the product reaction loop. This approach is illustrated using an
existing methanol production process, using wastes as sustainable raw materials, including electricity
cogeneration during the reaction loop and exhaust gas, generating a possible increase in annual profit
of 7.28 MEUR/a. Ključne besede: waste recovery, cogeneration, exothermic reactor, gas turbine, exhaust gas, combined compressor Objavljeno v DKUM: 15.05.2025; Ogledov: 0; Prenosov: 0
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7. Integration of an absorption chiller to a process applying the pinch analysis approachAndreja Nemet, Zdravko Kravanja, Miloš Bogataj, 2022, izvirni znanstveni članek Opis: In addition to the consumption of hot utilities, there is also a significant cost associated
with the consumption of cold utilities when there is a high demand for cooling. A promising
solution for cooling is an absorption chiller (AC), which uses heat instead of electricity for cooling.
A thermodynamic approach for evaluating AC integrated with a process is presented in this work.
A model for assessing the properties and duties of an AC cycle was developed. The integration of
a combined process-AC system was evaluated using the Grand Composite Curve. Three different
options of integration were analyzed: (i) above the Pinch, (ii) below the Pinch, and (iii) across the
Pinch. AC represents the combined effect of a heat engine and a heat pump, as the generator together
with the absorber and condenser has the function of a heat engine, while the evaporator combined
with the absorber and condenser mimics the function of a heat pump. The comparison between the
non-integrated and integrated process-AC systems has revealed that the proper placement of AC is
across or below the Pinch and the improper is above the Pinch. If AC was entirely integrated below
the Pinch, the integration would result in a complete (100%) reduction in the consumption of hot
utility for the operation of AC. The most suitable placement of AC with double reduction of hot
utility consumption and complete reduction of both hot and cold utility to operate AC is across the
Pinch due to the pumping of heat through AC from below to above the Pinch. Ključne besede: absorption chiller, Pinch analysis, heat integration, low-temperature heat Objavljeno v DKUM: 15.05.2025; Ogledov: 0; Prenosov: 1
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8. Comparison of the new refrigerant R1336mzz(E) with R1234ze(E) as an alternative to R134a for use in heat pumpsJan Drofenik, Danijela Urbancl, Darko Goričanec, 2022, izvirni znanstveni članek Opis: R134a is currently the most widely used refrigerant, whose problem is the high value of the
global warming potential, and which will have to be replaced in the near future. Thus far, R1234ze(E)
has proven to be the most suitable alternative, but it is slightly flammable. Recently, R1336mzz(E) has
emerged as a possible alternative. During the research, the mentioned refrigerants were compared
with simulations using the Aspen Plus software package in the case of using groundwater as a heat
source. It was found that R1336mzz(E) could be a suitable alternative to R134a since the highest
value of coefficient of performance was obtained using it. However, it must be superheated with an
internal heat exchanger. The problem with using an internal heat exchanger is that the superheating
of the refrigerant vapors affects the isentropic efficiency of the heat pump compressor negatively and,
consequently, lowers the COP value of the heat pump. It has been shown that a one percent decrease
in isentropic efficiency results in a one percent decrease in the COP value. Ključne besede: heat pump, internal heat exchanger, HFO, HFC alternative, GWP Objavljeno v DKUM: 15.05.2025; Ogledov: 0; Prenosov: 0
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9. Emulsion templated porous poly(thiol-enes): influence of photopolymerisation, emulsion composition, and phase behaviour on the porous structure and morphologyViola Hobiger, Muzafera Paljevac, Peter Krajnc, 2022, izvirni znanstveni članek Opis: 1,6-hexanediol diacrylate (HDDA) or divinyl adipate (DVA) and pentaerythritol tetrakis(3-
mercaptopropionate) (TT) were polymerised via a thiol-ene radical initiated photopolymerisation
using emulsions with a high volume fraction of internal droplet phase and monomers in the continuous phase as precursors. The porous structure derived from the high internal phase emulsions
(HIPEs) followed the precursor emulsion setup resulting in an open porous cellularly structured
polymer. Changing the emulsion composition and polymerisation conditions influenced the resulting
morphological structure significantly. The investigated factors influencing the polymer monolith
morphology were the emulsion phase ratio and surfactant concentration, leading to either interconnected cellular type morphology, bicontinuous porous morphology or a hollow sphere inverted
structure of the polymerised monoliths. The samples with interconnected cellular morphology had
pore diameters between 4 µm and 10 µm with approx. 1 µm sized interconnecting channels while
samples with bicontinuous morphology featured approx. 5 µm wide pores between the polymer
domains. The appropriate choice of emulsion composition enabled the preparation of highly porous
poly(thiol-enes) with either polyHIPE or bicontinuous morphology. The porosities of the prepared
samples followed the emulsion droplet phase share and could reach up to 88%. Ključne besede: high internal phase emulsions, thiol-ene polymerisation, polyHIPE, bicontinuous structure, phase inversion, poly(thiol-enes) Objavljeno v DKUM: 13.05.2025; Ogledov: 0; Prenosov: 0
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10. Natural Deep Eutectic Solvent-Based Matrix Solid Phase dispersion (MSPD) extraction for determination of bioactive compounds from sandy everlasting (Helichrysum arenarium L.) : a case of stability studyMilena Ivanović, Peter Krajnc, Aleš Mlinarič, Maša Islamčević Razboršek, 2022, izvirni znanstveni članek Opis: In the present study, vortex-assisted matrix solid-phase dispersion (VA-MSPD) extraction
was used to isolate the major bioactive compounds from H. arenarium. To reduce the negative environmental impact of the conventionally used organic solvents, four different choline chloride-based
natural deep eutectic solvents (NADES) were investigated as possible eluents. The most influential
VA-MSPD extraction parameters: stationary phase (adsorbent), adsorbent/sample ratio, vortex time,
and volume of extraction solvent were systematically optimized. Ultrasound-assisted extraction
with 80% MeOH was used as the standard method for the comparison of results. The stability of the
obtained extracts was studied over a period of 0 to 60 days at three different temperatures (−18 ◦C,
4
◦C, and 25 ◦C). All extracts were evaluated both spectrophotometrically (determination of total
phenolic content (TPC) and antioxidant activity by ABTS and FRAP assay) and chromatographically
(HPLC-UV). NADES based on choline chloride and lactic acid (ChCl-LA) was selected as the most
effective extractant, with a determined TPC value of its extract of 38.34 ± 0.09 mg GA/g DW (27%
higher than the methanolic VA-MSPD extract) and high antioxidant activity. The content of individual phenolic compounds (chlorogenic acid, dicaffeoylquinic acid isomers, naringenin isomers,
and chalcones) in the ChCl-LA extract, determined by HPLC-UV, was comparable to that of the
conventionally obtained one. Moreover, the stabilization effect of ChCl-LA was confirmed for the
studied compounds: chlorogenic acid, naringenin-40
-O-glucoside, tomoroside A, naringenin-5-Oglucoside, isosalipurposide, and naringenin. The optimum VA-MSPD conditions for the extraction of
H. arenarium polyphenols were: florisil/sample ratio of 0.5/1, a vortex time of 2 min, and an elution
volume of ChCl-LA of 10 mL. Ključne besede: matrix solid phase dispersion extraction, MSPD, natural deep eutectic solvents, NADES, extraction optimization, sandy everlasting, phenolic compounds, stability studies, antioxidant activity Objavljeno v DKUM: 09.05.2025; Ogledov: 0; Prenosov: 3
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