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1.
Research trends in motivation and weight loss : a bibliometric-based review
Uroš Železnik, Peter Kokol, Jasmina Starc, Danica Železnik, Jernej Završnik, Helena Blažun Vošner, 2023, review article

Abstract: Obesity is a complex disease that, like COVID-19, has reached pandemic proportions. Consequently, it has become a rapidly growing scientific field, represented by an extensive body of research publications. Therefore, the aim of this study was to present the research trends in the scientific literature on motivation and weight loss. Because traditional knowledge synthesis approaches are not appropriate for analyzing large corpora of research evidence, we utilized a novel knowledge synthesis approach called synthetic knowledge synthesis (SKS) to generate new holistic insights into obesity research focusing on motivation. SKS is a triangulation of bibliometric analysis, bibliometric mapping, and content analysis. Using it, we analyzed the corpus of publications retrieved from the Scopus database, using the search string TITLE-ABS-KEY((obesity or overweight) and “weight loss” and motiv*) in titles, keywords, and abstracts, without any additional inclusion or exclusion criteria. The search resulted in a corpus of 2301 publications. The United States of America, the United Kingdom, and Australia were the most productive countries. Four themes emerged, namely, weight loss and weight-loss maintenance through motivational interventions, lifestyle changes supported by smart ICT, maintaining sustainable weight with a healthier lifestyle, and weight management on the level of primary healthcare and bariatric surgery. Further, we established that the volume of research literature is growing, as is the scope of the research. However, we observed a regional concentration of research and its funding in developed countries and almost nonexistent research cooperation between developed and less-developed countries.
Keywords: obesity, weight loss, motivation, synthetic knowledge synthesis, bibliometrics, content analysis
Published in DKUM: 05.06.2024; Views: 62; Downloads: 4
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2.
Microwave Synthesis of Poly(Acrylic) Acid-Coated Magnetic Nanoparticles as Draw Solutes in Forward Osmosis
Sabina Vohl, Irena Ban, Mihael Drofenik, Hermina Bukšek, Sašo Gyergyek, Irena Petrinić, Claus Hélix-Nielsen, Janja Stergar, 2023, original scientific article

Abstract: Polyacrylic acid (PAA)-coated magnetic nanoparticles (MNP@PAA) were synthesized and evaluated as draw solutes in the forward osmosis (FO) process. MNP@PAA were synthesized by microwave irradiation and chemical co-precipitation from aqueous solutions of Fe2+ and Fe3+ salts. The results showed that the synthesized MNPs have spherical shapes of maghemite Fe2O3 and superparamagnetic properties, which allow draw solution (DS) recovery using an external magnetic field. Synthesized MNP, coated with PAA, yielded an osmotic pressure of ~12.8 bar at a 0.7% concentration, resulting in an initial water flux of 8.1 LMH. The MNP@PAA particles were captured by an external magnetic field, rinsed in ethanol, and re-concentrated as DS in repetitive FO experiments with deionized water as a feed solution (FS). The osmotic pressure of the re-concentrated DS was 4.1 bar at a 0.35% concentration, resulting in an initial water flux of 2.1 LMH. Taken together, the results show the feasibility of using MNP@PAA particles as draw solutes.
Keywords: magnetic nanoparticles, microwave synthesis, polyacrilic acid, osmotic pressure, draw solution, forward osmosis
Published in DKUM: 05.12.2023; Views: 350; Downloads: 15
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3.
Acetan and acetan-like polysaccharides: genetics, biosynthesis, structure, and viscoelasticity
Janja Trček, Iztok Dogša, Tomaž Accetto, David Stopar, 2021, review article

Abstract: Bacteria produce a variety of multifunctional polysaccharides, including structural, intracellular, and extracellular polysaccharides. They are attractive for the industrial sector due to their natural origin, sustainability, biodegradability, low toxicity, stability, unique viscoelastic properties, stable cost, and supply. When incorporated into different matrices, they may control emulsification, stabilization, crystallization, water release, and encapsulation. Acetan is an important extracellular water-soluble polysaccharide produced mainly by bacterial species of the genera Komagataeibacter and Acetobacter. Since its original description in Komagataeibacter xylinus, acetan-like polysaccharides have also been described in other species of acetic acid bacteria. Our knowledge on chemical composition of different acetan-like polysaccharides, their viscoelasticity, and the genetic basis for their production has expanded during the last years. Here, we review data on acetan biosynthesis, its molecular structure, genetic organization, and mechanical properties. In addition, we have performed an extended bioinformatic analysis on acetan-like polysaccharide genetic clusters in the genomes of Komagataeibacter and Acetobacter species. The analysis revealed for the first time a second acetan-like polysaccharide genetic cluster, that is widespread in both genera. All species of the Komagataeibacter possess at least one acetan genetic cluster, while it is present in only one third of the Acetobacter species surveyed.
Keywords: extracellular polysaccharide, acetan, acetan genetic cluster, acetan synthesis, acetan viscoelasticity, applications of acetan, Komagataeibacter, Acetobacter
Published in DKUM: 02.09.2022; Views: 560; Downloads: 9
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4.
Synthesis, crystal structure and magnetic properties of a new hydroxylammonium fluoroferrate
Brina Dojer, Matjaž Kristl, Zvonko Jagličić, Amalija Golobič, Marta Kasunič, Mihael Drofenik, 2012, original scientific article

Abstract: This paper reports on the synthesis of a new hydroxylammonium fluoroferrate, with the formula $(NH_3OH)_3FeF_6$, obtained after dissolving iron powder in hydrofluoric acid and adding solid $NH_3OHF$. This new compound has been characterized by chemical and thermal analysis, single-crystal X-ray diffraction, and magnetic measurements. The title compound crystallizes trigonal, R3c, with cell parameters a = 11.4154(2) Å, c = 11.5720(2) Å, Z = 6. The structure consists of $NH_3OH^+$ cations and isolated $FeF_6^{3–}$ octahedra in which the central ion lies on a threefold axis. The oxygen and nitrogen atoms of the hydroxylammonium cations are donors of hydrogen bonds to fluoride anions, resulting in a network of hydrogen bonds between counterions. The effective magnetic moment $µ_{eff}$ = 5.8 BM was calculated and perfectly matches the expected value of high-spin Fe(III) ions. The thermal decomposition of the compound was studied by TG, DSC, and X-ray powder diffraction.
Keywords: inorganic chemistry, crystallography, coordination compounds, synthesis, crystal structure, characterization of compounds, determination of the structure of compounds, X-ray diffraction, magnetic measurements, thermal analysis, TG, DSC, hydrogen bond, metal complexes, hydroxylammonium fluoromethalatehydroxylammonium, fluoroferrate
Published in DKUM: 25.08.2017; Views: 2004; Downloads: 67
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5.
Synthesis and characterisation of hydroxylammonium fluorochromate
Matjaž Kristl, Mihael Drofenik, Ljubo Golič, Amalija Golobič, 2003, original scientific article

Abstract: Reactions in the system $Cr – NH_3OHF – HF – H_2O$ were investigated. Green crystals of a new compound with the formula $(NH_3OH)_3CrF_6$ have been isolated from the water solution and characterized by chemical analysis. The compound crystallizes as triclinic, P-1, with cell parameters: a = 6.5461(2) Å, b = 6.9347(2) Å, c = 9.4072(3) Å, α = 86.772(1)°, β = 83.804(1)°, γ = 70.283(1)°. The effective magnetic moment, $µ_{eff}$ = 3.82 BM, was calculated from magnetic susceptibility measurements in the temperature range 80-290 K. The thermal decomposition of the compound was studied by TG and DSC analysis. $(NH_3OH)_3CrF_6$ decomposes above 125 °C in three steps and the residue has been identified by X-ray powder diffraction as $α – Cr_2O_3$.
Keywords: inorganic chemistry, structural chemistry, crystalline structure, coordination compounds, synthesis, inorganic reactions, thermal decomposition, characterization of compounds, TG, DSC, X-ray diffraction, chromium complexes, hydroxylammonium fluoro chromates, crystals
Published in DKUM: 25.08.2017; Views: 1800; Downloads: 110
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6.
Multi-objective synthesis of company’s supply-networks based on integration of renewable resources
Annamaria Vujanović, 2017, doctoral dissertation

Abstract: The aim of this doctoral dissertation was to develop a general methodology for sustainable integration of company's supply networks into nearby regional networks by i) integrating renewables, thereby increasing company's energy self-sufficiency, ii) by performing multi-objective synthesis in order to obtain economically efficient and yet environmentally benign or even unburdening solutions, and iii) to perform dynamic and stochastic synthesis under uncertainties in dynamically changing market conditions in order to obtain more reliable and realistic solutions. The research work is directly interlinked with a large-scale European meat producing company Perutnina Ptuj d.d., which is located in the heart of Slovenia. The aim of the first part was to integrate renewables into companies’ supply-networks at regional level in order to maximize the self-sufficiencies of their energy supplies. This concerns companies’ activities from the use of natural resources to supplying their final products to the customers being interlinked with their regional networks. A Mixed-Integer Linear Programming (MILP) model has been developed for the integration of both the companies’ and surrounding regional supply-networks and the utilization of different types of renewables as sources for the companies’ energy supplies. The potential renewable energy sources, which are located within companies surrounding region are solar, biomass, organic and animal wastes. The result indicates that by sufficient integration of renewables into companies’ supply networks, profitable and yet energy self-sufficient solutions can be obtained. The second part presents the multi-objective synthesis of a company’s supply-network by integrating renewables and accounting for several environmental footprints. A previously developed model for achieving energy self-sufficiency by integrating renewables into companies’ supply-networks has been extended for the evaluation of environmental impacts, such as energy, carbon, nitrogen, and water footprints. The achievement of an energy self-sufficient supply-network has been considered whilst significantly reducing environmental impacts. Direct (burdening) and indirect (unburdening) effects that form total effects on the environment are considered for the evaluation of environmental footprints. This approach identifies those alternative energy production technologies that are more profitable and environmentally more benign with significant unburdening capabilities. The results showed significant unburdening of the environment in terms of carbon and nitrogen footprints; however, higher burdening in terms of the water footprint. The third part presents a multi-objective MILP synthesis of a dynamic supply-network under uncertainty applied to the company. The previously-developed multi-objective model for achieving energy self-sufficiency by integrating renewables into companies’ supply-networks has now been extended to account for the dynamic consideration of variable supply and demand over the year, for uncertainties related to products’ demand and sun radiation, and for multi-objective optimisation, in order to obtain the most sustainable company’s supply-network. The sustainable synthesis of a company’s network is performed regarding the integration of the renewables such as biomass and other wastes, and solar energy. The obtained solutions are those reflecting maximal profit, reflecting constantly-changing dynamic market conditions, accounting for several uncertain parameters, and protecting the environment.
Keywords: Company's supply network, Renewables, Environmental Impacts, Dynamic synthesis, Flexibility, Multi-objective optimisation, Uncertainty
Published in DKUM: 21.07.2017; Views: 1620; Downloads: 166
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7.
Synthesis of nanocrystalline nickel-zinc ferrites within reverse micelles
Vuk Uskoković, Mihael Drofenik, 2003, original scientific article

Abstract: Nanocrystalline nickel-zinc ferrites were synthesized via a reverse micelle microemulsion route. The precursor cations were precipitated in the microemulsion system CTAB/1-hexanol/water. A subsequent oxidizing reaction was used to synthesize the nickel-zinc ferrite. The obtained nanoparticles were less than 20 nm in size.
Keywords: nanomaterials, ferrite, powders synthesis, microemulsion, reverse micelle
Published in DKUM: 23.03.2017; Views: 1050; Downloads: 109
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8.
SYNTHESIS OF SUSTAINABLE BIOPROCESSES USING COMPUTER-AIDED PROCESS ENGINEERING
Lidija Čuček, 2013, doctoral dissertation

Abstract: This doctoral dissertation, which consists of four substantive wholes, presents several syntheses of sustainable bioprocesses using computer-aided process engineering. In the first part the synthesis of different integrated processes of ethanol production from the entire corn plant is presented. The synthesis of different processes is in the second part further extended to the simplified and more comprehensive synthesis of bioproducts in the whole production supply chain network. Synthesis is based on the generic optimisation model of biomass production and supply chain networks. In the third part three methods for sustainable development assessment, suitable for multi-criteria optimisation, are presented: method of sustainability indexes, footprints and combined criteria, such as eco- and total profit. Methods are further upgraded with indirect effects in order to measure the unburdening the environment, associated with the use and replacement of environmentally-harmful products. Methods include the direct, indirect and total impacts on the environment. In the last part the methodology for reducing a large number of criteria within multi-objective optimisation to a small number of representative criteria is presented. This method is presented on the case of environmental footprints.
Keywords: Biomass energy generation, Supply chain networks, Synthesis of sustainable bioprocesses, Life Cycle Analysis, Sustainability assessment, Multi-objective optimisation, Dimensionality reduction, Representative Objectives Method
Published in DKUM: 06.05.2013; Views: 2534; Downloads: 280
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9.
Preparation of Au[sub]2S[sub]3 and nanocrystalline gold by sonochemical method
Matjaž Kristl, Mihael Drofenik, 2003, original scientific article

Abstract: We report a new synthesis of ▫$Au_2S_3$▫ by a sonochemical reaction between ▫$Au(CH_3COO)_3$▫ and S in decalin at room temperature in nitrogen atmosphere. When gold acetate is sonicated under similar conditions without the presence of sulfur, nanocrystalline gold is formed. The products were characterised by X-ray powder diffraction, transmission electron microscope and thermal analysis (IG and DSC). The synthesis procedure is substantially simpler than the previously reported methods.
Keywords: sonochemistry, sonochemical reactions, gold, sulfides, sonochemical synthesis, nanostructures
Published in DKUM: 01.06.2012; Views: 1804; Downloads: 44
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10.
The characterisation of nanosized nickel-zinc ferrites synthesized within reverse micelles of CTAB/1-hexanol/water microemulsion
Vuk Uskoković, Mihael Drofenik, Irena Ban, 2004, original scientific article

Abstract: Stoichiometric nanocrystalline nickel-zinc ferrites were synthesized by a reverse micelle method following a multi-microemulsion approach. Different pH values were chosen for the alkali precipitating reaction during the synthesis of different powders. Synthesized, as-dried and subsequently calcined powders were characterized in terms of their magnetic properties. XRD analyses and specific-surface area measurements were used to determine the average particlesizes of the synthesized samples. DCS and TGA measurements were performed to reveal the phase transitions within the samples at elevated temperatures, whereas TEM was used to view and record the microstructure of the nanosized ferrite samples. A possible mechanism of the formation of the synthesized NiZn-ferrite was also discussed.
Keywords: magnetic materials, magnetic nanoparticles, microemulsion synthesis, nickel, iron, fine powders, Ni-Zn ferrites, reverse micelle method
Published in DKUM: 01.06.2012; Views: 1992; Downloads: 53
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