1. Integrated optimization framework for a biomass supply network and steam Rankine cycleMonika Dokl, Zdravko Kravanja, Lidija Čuček, 2024, izvirni znanstveni članek Opis: The optimization of biomass supply chains is becoming increasingly important, especially for low-density biomass feedstocks that have limited market value and require efficient handling and logistics. This study addresses this issue by proposing an integrated approach to optimize biomass supply chain networks for energy production with the steam Rankine cycle. The approach takes into account the inherent variability of feedstock availability and energy market values, to ensure adaptability to fluctuating conditions. The biomass supply network is formulated as a mixed-integer nonlinear programming problem, where the optimization objective is to maximize the economic viability of the system. The optimal configuration of the supply network includes the selection of biomass supply zones and storage facilities, the transportation links, and the optimization of the process variables within the conversion plants, taking into account the variable heat demand. The optimization approach is applied to a hypothetical case study of a relatively small region in Slovenia. The results show the economic viability of biomass utilization with a net present value of almost 300 MEUR, generating about 4 MW of electricity and 65 MW of heat. The uncertainties of the biomass supply, the fluctuations in product prices and the spatial scope of the case study are evaluated in addition. This analysis highlights and discusses the impact of these factors on the economic performance of the biomass supply chain network. Ključne besede: copper(II) coordination compounds, methylamines, crystal structure, magnetic properties, thermogravimetric analysis Objavljeno v DKUM: 31.01.2025; Ogledov: 0; Prenosov: 3
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2. Two new zinc(II) acetates with 3- and 4-aminopyridine : syntheses and structural propertiesBrina Dojer, Andrej Pevec, Ferdinand Belaj, Matjaž Kristl, 2015, izvirni znanstveni članek Opis: The synthesis and characterization of two new zinc(II) coordination compounds with 3- and 4-aminopyridine are reported. They were obtained after adding a water solution of $Zn(CH_3COO)_2$ · $2H_2O$ or dissolving solid $Zn(CH_3COO)_2$ · $2H_2O$ in methanol solutions of 3- and 4-aminopyridine. The products were characterized structurally by single-crystal X-ray diffraction analysis. Colourless crystals of the compound synthesized by the reaction of $Zn(CH_3COO)_2$ · $2H_2O$ and 3-aminopyridine (3-apy), are built of trinuclear complex molecules with the formula $[Zn_3(O_2CCH_3)_6(3- apy)_2(H_2O)_2]$(1). The molecules consists of two terminal $Zn$ atoms, coordinated tetrahedrally, and one central $Zn$ atom, coordinated octahedrally. Colourless crystals, obtained by the reaction of $Zn(CH_3COO)_2$ · $2H_2O$ with 4-aminopyridine (4-apy), consist of a mononuclear complex $[Zn(O_2CCH_3)_2(4-apy)_2]$(2). Hydrogen-bonding interactions in the crystal structures of both complexes are reported. Ključne besede: zinc(II) acetate dihydrate, aminopyridine, x-ray crystal structure, hydrogen bonds Objavljeno v DKUM: 30.08.2017; Ogledov: 1913; Prenosov: 158
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3. Synthesis, crystal structure and magnetic properties of a new hydroxylammonium fluoroferrateBrina Dojer, Matjaž Kristl, Zvonko Jagličić, Amalija Golobič, Marta Kasunič, Mihael Drofenik, 2012, izvirni znanstveni članek Opis: 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. Ključne besede: 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 Objavljeno v DKUM: 25.08.2017; Ogledov: 2076; Prenosov: 70
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4. The crystal and molecular structures of two reaction products of geminal dicyano oxirane with thiohydantoine (compound I) and thioxobenzoxazole (compound II)Ivan Leban, Alenka Majcen Le Marechal, Albert Robert, 1993, izvirni znanstveni članek Opis: The crystal and molecular structures of two reaction products of geminal dicyano oxiranes with thiohydantoione and thioxobenzoxazole have been determinated from ▫$Mo-K_\alpha$▫ X-ray diffraction data. The two reaction products were: 2H-2-(p-tolyl)-imidazol[1,2-b]thiazole-3,6-dione (compound I) and Z-3-benzoxazole-3-phenyl-2-oxo-2-propanenitrile (compound II) with the following crystal data at 293(1) K: Compound I, ▫$C_{12}H_{10}N_2O_2S$▫, monoclinic ▫$P2_1/c$▫, a=15057(3), b=5.200(3), c=14.724(4) Å, ▫$\beta=104.24(3)°$▫, Z=4; final R and ▫$R_w$▫ values were 0.034 and 0.049 for1647 observed reflexions. Compound II, ▫$C_{16}H{10}N_2O_2$▫, monoclinic, ▫$P2_1/n$▫, a=14.396(3), b=4.326(1), c=21.335(4) Å, ▫$\beta-107.79(1)°$▫, Z=4;final R and ▫$R_w$▫ values 0.040 and 0.053 for 1516 observed reflections. Ključne besede: organic chemistry, crystal structure, chemical reactions, oxiranes, coordination compounds, structural chemistry Objavljeno v DKUM: 05.07.2017; Ogledov: 1572; Prenosov: 118
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5. Crystal-structure and Mössbauer studies of Li[sub]1.746]Nd[sub]4.494FeO9[sub]9.493Mihael Drofenik, Irena Ban, Darko Makovec, Darko Hanžel, Amalija Golobič, Ljubo Golič, 2007, izvirni znanstveni članek Opis: The ▫$Li_1.746Nd_4.494FeO_9.493$▫ (LNF) ternary phase, located in the ▫$Li_2O$▫-rich part of the ▫$Li_2O-Nd_2O_3-Fe_2O_3$▫ system, crystallizes with a cubic unit cell of dimension and the space group Im3m. Refinement on F resulted in R=1.9%. The structure is comprised of a network of corners, edges and faces sharing the coordination polyhedra of neodymium. In between this skeleton the regular octahedra of oxygen-coordinated iron and trigonal prisms of lithium are located. The Mössbauer spectra revealed the presence of ▫$Fe^3+$▫, ▫$Fe^4+$▫ and ▫$Fe^5+$▫ ions distributed on two symmetry-independent lattice positions. Ključne besede: crystal structure, ternary compounds, single-crystal X-ray diffraction, Mössbauer spectroscopy, iron oxidation state, kristalna struktura, ternarne spojine, rentgenska difrakcija, Mössbauerjeva spektroskopija, rentgenska strukturna analiza Objavljeno v DKUM: 01.06.2012; Ogledov: 2701; Prenosov: 48
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