Инновации в химических науках. Рубрика в журнале - НБИ технологии
Статья научная
For the first time in the world practice the results of simulation by Monte Carlo method of the kinetics of three-dimensional free-radical polymerization of tetrafunctional monomers (TFM) have been obtained in the framework of the formation of a unitary three-dimensional structural element (UTDSE) and its structure formation on the simple cubic lattice, depending on the length l of molecules tetrafunctional monomers (l = 1 to 40 ribs of the lattice). Peculiarities of kinetics of changes in parameters such as the degree of polymerization of the Pn UTDSE, the number of radicals, the number of cross-links and cycles, and other characteristics are revealed. It is established that UTDSE are characterized by low levels of Pn, and an explanation of this phenomenon is given.
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Structure and parameters of polyhydroxybutyrate nanofibres
Статья научная
This research work focuses on process characteristics of polymer solutions, such as viscosity and electrical conductivity, as well as the parameters of electrospinning using poly-3-hydroxybutyrate modified by titanium dioxide nanoparticles, which have been optimized. The structure of materials has been examined by means of X-ray diffraction, differential scanning calorimetry (DSC), IR-spectroscopy, and physical-mechanical testing. The fibrous materials obtained can find a wide application in medicine and filtration techniques as scaffolds for cell growth, filters for body fluids and gas-air media, and sorbents.
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Vacancy transport properties in boron-carbon bc3 nanotubes
Статья научная
The paper presents results of theoretical research into vacancy formation in B type of boron-carbon nanotubes ВС n, where n = 3. The research was performed using the MNDO method within the framework of an ionic-embedded covalent-cyclic cluster model, molecular cluster model and DFT method. We found that when a V -defect (vacancy) is introduced in a boron-carbon nanotube, the band gap of the defective tubules increases. It means that physical properties of materials can be purposefully changed by introducing defects. Vacancy migration along the atomic bonds in the tubule was simulated and vacancy transport properties were studied. It was found that the defect migration along different bonds actually represents the process of carbon or boron ions hopping between their stable states on the nanotube surface. The calculated activation energy values revealed dependence of ionic conductivity in boron-carbon tubules on temperature.
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Влияние полярности растворителя на структуру полигидроксибутирата
Статья научная
В работе установлено, что с ростом полярности растворителя происходит совершенствование кристаллической структуры и уменьшение доли аморфной фазы полигидроксибутирата. Показано, что доля дефектной кристаллической фазы в пленках полигидроксибутирата прямо пропорциональна величине энергии когезии растворителя.
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