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The computer experiments on air bubble attachment and detachment with particles from 36 fractions of ore with different size and copper content display the influence of air bubble diameter and energy dissipation on the flotation selectivity. The concentration reached 80 at the optimized bubble diameter of 265 µm, which is 5-8 time higher than with the air bubble diameter of 1000-2000 µm standard for impeller flotation machines.

A novel mononuclear copper complex [Cu(NH ₂mpdH)(NH ₂mpd) ₂Cl] ( 1) is synthesized from 2-amino-2-methyl-1,3-propandiol (ampdH ₄). The crystal structure of (1) is determined using X-ray diffraction studies. The copper complex crystallizes in the triclinic space group P-1(2) with a = 6.10.48(4) Å, b = 10.0915(7) Å, c = 10.9249(9) Å, α = 95.925(6)°, β = 101.830(6)°, γ = 90.637(5)°, V = 649.53(95) Å ³ and Z = 2. The central copper(II) atom in ( 1) is coordinated by three oxygen and two nitrogen atoms possessing a five-coordinate distorted square pyramidal geometry arranged in a one dimensional polymeric chain. The ground state geometry of the mononuclear copper complex is optimized using the DFT/B3LYP/6-31G** (LANL2DZ) level of theory. Intra-molecular charge transfer is investigated based on the frontier molecular orbitals. The distribution pattern of the highest occupied molecular orbital and the lowest unoccupied molecular orbital is studied. Absorption spectra are computed using The time dependent density functional theory (TDDFT). The absorption wavelengths are calculated using different functionals, i.e., BHandHLYP, CAM-B3LYP, and LC-BLYP.

The structures of iron(III) and nickel(II) complexes with the composition [FeL ₂]Cl×H ₂O ( 1) and [Ni(HL ₂')]×DMSO×0.5H ₂O ( 2), where L and HL' are monodeprotonated residues of 1'-phthalazinylhydrazones of 2-acetyl benzimidazole and 1-phenyl-3-methyl-4-formyl-5-hydroxypyrazole respectively, are determined using single crystal X-ray diffraction analysis. Both compounds crystallize in the monoclinic symmetry. The Fe(III) and Ni(II) ions in the complexes have octahedral N ₆ and N ₄O ₂ donor environments respectively. Due to intermolecular hydrogen bonds, the molecules of the complexes form corrugated (complex 1) and linear (complex 2) molecular chains in the crystal.

A brief review of theoretical and experimental studies devoted to the design of novel magnetic materials based on non-magnetic semiconductor phases with the ZrCuSiAs structure type (such as LaCuSO, LaCuSeO, LaZnAsO, YZnAsO, or SrAgSeF) by doping their sublattices with magnetic and non-magnetic substitutional impurities is presented. Using the results of ab initio calculations of the band structure, we discuss the possibility of obtaining new magnetic semiconductors, magnetic metals and half-metals, and also gapless magnetic semiconductors and bipolar magnetic semiconductors based on the 1111 phases. The available experimental data on the synthesis and properties of materials based on semiconducting 1111 phases doped with atoms of alkali-earth and magnetic 3 d metals are discussed.

High-temperature silicon carbonitride films are synthesized by plasma decomposition of gas mixtures of 1,1,1,3,3,3-hexamethyldisilazane (HMDS) (the synonym used by IUPAC bis(trimethylsilyl) amine) with ammonia or helium in the temperature range of 673-1273 K. It is shown that silicon carbonitride films, obtained in high temperature processes of the plasma decomposition of organosilicon compounds, are nanocomposite. In their amorphous matrix the crystals belonging to the phases of the α-Si _{3- n}C _n N ₄ family and impurity graphite are embedded. To clarify the previously obtained data by means of the X-ray diffractometry using synchrotron radiation, they are compared with the published results of modeling the structure of these phases. It is shown that nanocrystals belonging to the phases of α-Si ₃N ₄, α-Si ₂CN ₄, α-SiC ₂N ₄, and α-C ₃N ₄ are present in the films. An increase in the ammonia concentration in the initial gas mixture causes a decrease in the film hardness from 24 GPa to 16 GPa due to the increased content of α-Si ₃N ₄ and α-Si ₂CN ₄ nanocrystals having a lower hardness compared to α-C ₃N ₄ and α-SiC ₂N ₄.

A mixed ligand copper(I) Schiff base complex [Cu(py-Clan)(PPh ₃)I], where py-Clan = 4-chlorophenylpyridine-2-ylmethyleneamine, is synthesized and structurally characterized by single crystal X-ray crystallography. In this complex, the copper(I) ion is in a distorted four-coordinate tetrahedral geometry. The Schiff base py-Clan ligand acts as a chelating ligand and coordinates to the copper center via two nitrogen atoms. The [Cu(py-Clan)(PPh ₃)I] complex crystallizes in the monoclinic space group P2 ₁/ c with unit cell parameters: a = 10.3339(12), b = 34.524, c = 8.3940 Å, β = 114.759(8)°, V = 2719.4(5) Å ³ and Z = 4.

The X-ray diffraction study of a single crystal with the composition [H ₂C(3,5-Me ₂pz)(3,5-Me ₂pzH)] ₂[UCl ₆] (1) is performed. This compound is the product of an attempted synthesis of a bis(pyrazolyl)methane complex of uranium(IV) obtained by the reaction of UCl ₄ with bis(3,5-dimethylpyrazol-1-yl)methane in THF. 1 crystallizes in the space group P-1 of the triclinic system: a = 9.6616(2) Å, b = 9.6946(2) Å, c = 10.7314(2) Å, α = 107.6210(10)°, β = 115.5600(10)°, γ = 99.6710(10)°, V = 810.45(3) Å ³, Z = 1, d _calc = 1.765 g/cm ³, μ = 5.528 mm ^-1, R ₁ = 0.0249. The structural unit consists of two separated [H ₂C(3,5-Me ₂pz)(3,5-Me ₂pzH)] ⁺ cations and a UCl ₆ ^2- anion. In the solid state structure of 1 several short intermolecular N-H⋯N and C-H⋯Cl contacts are identified suggesting the presence of hydrogen bonds.

In the interaction of methyl 1-bromocyclopentanecarboxylate with zinc and 1-phenylpropan-1,2-dione, 3,3:6,6-dibutano-3 a-methyl-6 a-phenyltetrahydrofuro[3,2- b]furan-2,5-dione is synthesized and its structure is determined by single crystal X-ray diffraction study.

Two Cu(I) coordination polymers {[Cu ₂(bibp) ₂]×bdc×3H ₂O} _n ( 1) and {[Cu ₃(bib) ₃]×btc×5H ₂O} _n ( 2), where bibp = 4,4'-bis(1-imidazol-1-yl)biphenyl, H ₂bdc = terephthalic acid, bib = 1,4-bis(1-imidazol-1-yl)benzene, H ₃btc = benzene-1,3,5-tricarboxylic acid, are synthesized under solvothermal conditions and characterized structurally. Complex 1 crystallizes in the triclinic form with the space group P-1, and Cu(1) is two-coordinated by two N atoms of bibp, Cu(2) is three coordinated from two N atoms of bibp and one water molecule. Complex 2 crystallizes in the triclinic form with the space group P-1; the copper ions are monovalent and two-coordinated by two N atoms of bib. The bdc and btc ligands are not coordinated with Cu ions, but play important roles in the generation of a 3D supramolecular structure of complexes 1 and 2 via weak interactions respectively.

A novel tetranuclear zinc(II) complex [Zn ₄Br ₄L ₂(H ₂L)], where L and H ₂L are the dianionic and zwitterionic forms of N, N'-bis(2-hydroxy-5-methoxybenzylidene)propane-1,3-diamine, is prepared and structurally characterized by elemental analysis, IR spectrum, and single crystal X-ray crystallography. The complex crystallizes in the monoclinic space group C2/ c, with unit cell dimensions a = 38.338(2) Å, b = 10.5662(5) Å, c = 17.4607(8) Å, β = 113.767(2)°, V = 6473.3(6) Å ³, Z = 4, R ₁ = 0.0686, and wR ₂ = 0.1752. The inner Zn atoms are five-coordinated in a square pyramidal geometry, and the outer Zn atoms are four-coordinated in a tetrahedral geometry. The intramolecular Zn⋯Zn distance is 3.103(1) Å.