


Том 469, № 1 (2016)
- Жылы: 2016
- Мақалалар: 3
- URL: https://journal-vniispk.ru/0012-5008/issue/view/9225
Chemistry
Chemistry of the CARBEX process: Identification of absorption bands of the ligands in the electronic spectra of aqueous solutions of Na4[UO2(CO3)3]
Аннотация
On the basis of consideration of hydration, hydrolysis, dissociation, polymerization, and ligand exchange that occur in aqueous solutions of U(VI) complexes, a new approach to the assignment of absorption bands of the ligands in electronic spectra of uranium(VI) carbonate complexes in the range 190–400 nm has been suggested. For the Na4[UO2(CO3)3] complex, the following assignment of absorption bands has been made: Na3[UO2(CO3)3]–, 258 nm; Na2[UO2(CO3)3]2–, 300 nm; and Na4[UO2(CO3)3], 330 nm.



Chemical Technology
Formation of composite scaffolds based on chitosan and calcium phosphate
Аннотация
Composite materials based on chitosan and calcium phosphates with the structure and properties close to those of natural human tissues were developed. The possibility of formation of biological apatite, i.e., octacalcium phosphate, was demonstrated. The increase in the strength characteristics was caused by crystallization of the octacalcium phosphate phase on the surface of the material pore space. The materials resemble the extracellular matrix of the body in their structure and composition and can find wide use in the regenerative medicine as a scaffold for osteogenic factors.



Textured tape substrates made of ternary alloys based on Cu–40%Ni–Me constantan for epitaxial deposition of buffer and superconducting layers
Аннотация
The structure was studied and the texture formation process was investigated in tapes made of Cu–Ni–Me ternary alloys (Me = Fe, Cr, V, or Mn) during cold deformation by rolling to a degree of ∼99% with subsequent recrystallization annealing. It was shown that it is generally possible to create a perfect cubic texture in a thin ribbon made of ternary alloys based on copper and nickel to which a period 4 d-element (iron, chromium, or vanadium) was added. This makes these tapes promising as substrates in the technology for producing second-generation high-temperature superconductor tapes. The optimal annealing conditions were determined, under which, in the studied alloys, a perfect biaxial near-single-crystalline texture can be obtained with a content of cubic grains {001}〈100〉 ± 10° on the surface of the textured ribbon of above 99%.


