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The controllable synthesis of carbon nanofibers (CNF) and composites based on CNF (Metals/CNF) is of particular interest. In the present work, the samples of CNF were produced via ethylene decomposition over Co-Pt (0-100 at.% Pt) microdispersed alloys prepared by a reductive thermolysis of multicomponent precursors. XRD analysis showed that the crystal structure of alloys in the composition range of 5-35 at.% Pt corresponds to a fcc lattice based on cobalt ( Fm- 3 m ), while the CoPt (50 at.% Pt) and CoPt 3 (75 at.% Pt) samples are intermetallics with the structure P 4/ mmm and Pm -3 m , respectively. The microstructure of the alloys is represented by agglomerates of polycrystalline particles (50-150 nm) interconnected by the filaments. The impact of Pt content in the Co 1-x Pt x samples on their activity in CNF production was revealed. The interaction of alloys with ethylene is accompanied by the generation of active particles on which the growth of nanofibers occurs. Plane Co showed low productivity (~5.5 g/g cat ), while Pt itself exhibited no activity at all. The addition of 15-25 at.% Pt to cobalt catalyst leads to an increase in activity by 3-5 times. The maximum yield of CNF reached 40 g/g cat for Co 0.75 Pt 0.25 sample. The local composition of the active alloyed particles and the structural features of CNF were explored.

A simple and convenient procedure for the production of highly dispersed porous Co-Pt alloys to be used as catalysts for the synthesis of nanostructured carbon fibers (CNF) has been developed. The technique is based on the thermal decomposition of specially synthesized multicomponent precursors in a reducing atmosphere. A series of porous single-phase alloys Co-Pt (10-75 at% Pt) have been synthesized. The alloys containing 75 and 50 at% Pt were identified by the x-ray diffraction analysis as the intermetallics CoPt 3 and CoPt, respectively. Within the region of 10-35 at% Pt, the synthesized alloys are represented by Co 1-x Pt x random solid solutions with face-centered cubic lattice. The alloys obtained are characterized by a porous structure consisting of assembled fragments with a size of 50-150 nm. The obtained alloys were tested in the catalytic chemical vapor deposition of the ethylene to CNF. A significant synergistic effect between Co and Pt in the synthesis of carbon nanomaterials (CNMs) was revealed. The yield of CNF (for 30 min reaction) for catalysts containing 25-35 at% Pt was 30-38 g(CNF)/g(cat), whereas those for Co (100%) and Pt (100%) samples were as low as 5.6 and >0.1 g(CNF)/g(cat), respectively. The produced CNM composed of fibers with a segmented structure was shown to be characterized by a rather high specific surface area (200-250 m 2 g -1 ) and structural homogeneity.

Thermal decomposition of (NH4)3[IrCl6]·H2O, (NH4)2[IrCl6] and (NH4)2[IrBr6] in reductive and inert atmospheres has been investigated in situ using quick-EXAFS and temperature-resolved powder X-ray diffraction. For the first time, (NH4)2[Ir(NH3)Cl5] and (NH4)2[Ir(NH3)Br5] have been proven as intermediates of thermal decomposition of (NH4)3[IrCl6]·H2O, (NH4)2[IrCl6] and (NH4)2[IrBr6]. Thermal degradation of (NH4)2[IrCl6] and (NH4)2[IrBr6] is a more complex process as suggested previously and includes simultaneous formation of (NH4)2[Ir(NH3)Cl5] and (NH4)2[Ir(NH3)Br5] intermediates mixed with metallic iridium. In the inert atmosphere, complexes (NH4)[Ir(NH3)2Cl4] and (NH4)[Ir(NH3)2Br4] as well as [Ir(NH3)3Br3] were proposed as possible intermediates before formation of metallic iridium particles.

Immunoglobulin-G4-related disease (IgG4-RD) is a chronic immunomediated pathology of different organs of local or systemic nature, which has been established as a separate clinical entity in the early 2000s and is characterized by storiform fibroid inflammation of the affected tissues, their increase, and elevated serum immunoglobulin-G4 (IgG4) levels. The most common manifestations of the disease are major salivary and lacrimal gland enlargement, lymphadenopathy and type 1 autoimmune pancreatitis (AIP1), however, other organs may be also involved (the thyroid, eyes, meninges, heart, lungs, kidneys, aorta, upper airways, mesentery, etc.). The effectiveness of treatment of IgG4-RD, as well as other pathological conditions, is also determined by the timely diagnosis. However, the latter is complicated due to the variety of clinical manifestations and rather variable diagnostic criteria. It is necessary to constantly update the evidence-based knowledge and diagnostic algorithms within this pathology in order to overcome the difficulties, and involve immunologists, endocrinologists, pathologists and specialists in other spheres. This review provides information about the etiology, pathogenesis, and current methods of diagnosis and treatment of IgG4-related diseases, as well as examples of some manifestations of IgG4-RD that an endocrinologist may face in practice.

A mixture of rhodium(iii) hydroxocomplexes formed during the polycondensation process in alkaline media has been fully characterized by the hyphenated high performance liquid chromatography with electrospray ionization mass spectrometry (HPLC-ESI-MS). The baseline separation was achieved using reverse phase ion-pair chromatography (RP-IP-HPLC) in gradient elution mode. When using SDS as the ion pair, the formation of all types of its associates with the molecules of acetonitrile, as well as oligomers of rhodium aquahydroxocomplexes, etc. was taken into consideration. As a result, it was shown that the test mixture is presented by [Rh(H2O)6]3+, [Rh2(μ-OH)2(H2O)8]4+, [Rh3(μ-OH)4(H2O)10]5+, [Rh4(μ-OH)6(H2O)12]6+.

The expediency of capillary zone electrophoresis application in the study of a mixture of rhodium(iii) hydroxocomplexes is shown for the species formed during the thermal treatment of [Rh(OH) 6 ] 3- at 60 °C in alkaline media. As these compounds are unstable in solution because of polycondensation at pH > 10 and the formation of insoluble rhodium(iii) hydroxides at pH 5-10, their acidic derivatives with terminal aqua ligands acted as the objects of the study. Optimal separation conditions were achieved using sodium perchlorate as a background electrolyte, a voltage of +20 kV and pH 2.6. Rhodium(iii) species with different nuclearities were identified in accordance with their UV spectra and the regularities of electrophoretic migration in the capillary. The presence of a dimer was also verified by the spiking of the mixture under investigation with a previously synthesised complex [Rh 2 (μ-OH) 2 (H 2 O) 8 ](NO 3 ) 4 , which confirms the correct identification.

The hydrolysis of [RhCl 6 ] 3- in NaOH-water solutions was studied by spectrophotometric methods. The reaction proceeds via successive substitution of chloride with hydroxide to quantitatively form [Rh(OH) 6 ] 3- . Ligand substitution kinetics was studied in an aqueous 0.434-1.085 M NaOH matrix in the temperature range 5.5-15.3 °C. Transformation of [RhCl 6 ] 3- into [RhCl 5 (OH)] 3- was found to be the rate-determining step with activation parameters of ΔH † = 105 ± 4 kJ mol -1 and ΔS † = 59 ± 10 J K -1 mol -1 . The coordinated hydroxo ligand(s) induces rapid ligand substitution to form [Rh(OH) 6 ] 3- . By simulating ligand substitution as a dissociative mechanism, using density functional theory (DFT), we can now explain the relatively fast and slow kinetics of chloride substitution in basic and acidic matrices, respectively. Moreover, the DFT calculated activation energies corroborated experimental data that the kinetic stereochemical sequence of [RhCl 6 ] 3- hydrolysis in an acidic solution proceeds as [RhCl 6 ] 3- → [RhCl 5 (H 2 O)] 2- → cis-[RhCl 4 (H 2 O) 2 ] - . However, DFT calculations predict in a basic solution the trans route of substitution [RhCl 6 ] 3- → [RhCl 5 (OH)] 3- → trans-[RhCl 4 (OH) 2 ] 3- is kinetically favored.