Research Article
Thermal Vacuum Synthesis: Physical Processes in Nanomaterial Production
Volodymyr Kutovyi*
Issue:
Volume 12, Issue 4, August 2024
Pages:
69-77
Received:
12 October 2024
Accepted:
4 November 2024
Published:
26 November 2024
DOI:
10.11648/j.ajpa.20241204.11
Downloads:
Views:
Abstract: The thermovacuum process offers an efficient and cost-effective method for producing nanomaterials by ensuring the continuous flow of dispersed material inside a spiral heating element. This is achieved by introducing the material into the heating element's cavity along with air, forming a two-phase gas-solid particle system. The material moves upward through the heated space, where pressure gradually decreases. Experimental studies on materials like carbon, brown coal, and zirconium dioxide indicate specific conditions are necessary for the system's continuous operation. One key requirement is that the mass of solid particles should not exceed 1.0 to 1.2 grams per liter of air entering the heating element. This limit ensures that nanodispersed and finely dispersed particles can move freely, avoiding collisions and allowing faster-moving particles to overtake slower ones. These particles increase in velocity and temperature as they pass through the heating element, with changes in heat capacity and particle motion contributing to wave motion and pulsed heat loads. The velocity at which the material particles travel depends on the thermal radiation from the heater walls and the energy generated by local pulse steam explosions, which create shock waves. Higher explosion energy results in increased particle velocity, greater impact angles against the heater walls, and higher environmental temperatures. These conditions lead to accelerated electron, proton, and other charged particle flows, forming plasma clots and neutrino clouds. The nanoparticles take various forms, including nanotubes, fullerenes, thin films, and crystals, reaching velocities up to a thousand kilometers per second and heating temperatures of up to 17 million degrees during pulses. This process consistently subjects the material to force, heat, deformation, and ionization, expediting the creation of nanodispersed materials with enhanced physicochemical and mechanical properties. The thermovacuum process not only improves the efficiency of thermotechnological equipment but also reduces energy consumption, production time, and costs. The research findings support its use in the continuous and effective production of high-quality nanomaterials.
Abstract: The thermovacuum process offers an efficient and cost-effective method for producing nanomaterials by ensuring the continuous flow of dispersed material inside a spiral heating element. This is achieved by introducing the material into the heating element's cavity along with air, forming a two-phase gas-solid particle system. The material moves upw...
Show More
Research Article
The Mechanism of Formation of the Vibrational-Rotational Spectrum of the HCL Molecule
Gulshan Nurmurodova*,
Gulomhon Murodov,
Utkir Khujamov
Issue:
Volume 12, Issue 4, August 2024
Pages:
78-87
Received:
20 September 2024
Accepted:
16 October 2024
Published:
3 December 2024
DOI:
10.11648/j.ajpa.20241204.12
Downloads:
Views:
Abstract: In this work, the harmonic and anharmonic vibrational frequencies of the HCl molecule have been determined by using the density functional theory method. Calculations have been performed at the B3LYP/6-311++G (3dp, 3df) levels of theory. Transitions between energy levels are analyzed in terms of wavenumber. The rotational constants of the HCl molecule, the wavenumbers corresponding to the rotational structure of the P, R, and Q branches in the spectrum, and their relative intensities at temperatures of 100, 200, and 300 K are calculated, and vibrational-rotational spectra are simulated. The vibrational-rotational spectrum of the HCl molecule is obtained in the range of 2600-3100 cm-1. It has been theoretically shown that when the distance between atomic nuclei in the HCl molecule increases compared to the steady state, the R branch in the spectrum, and when it decreases, the P branch is formed. Rotational constants and corresponding frequencies are calculated for each fundamental transition in rotational energy levels. All calculations use empirical and non-empirical methods. For H35Cl and H37Cl molecules, graphs of the number of fundamental transitions (m) in rotational energy levels and the wave number corresponding to these transitions are drawn. It is in good agreement with all scale experiment results. It is verified that the rotational constants (B) corresponding to the general degree of degeneration (2J+1)2 are similar to the values observed in the literature.
Abstract: In this work, the harmonic and anharmonic vibrational frequencies of the HCl molecule have been determined by using the density functional theory method. Calculations have been performed at the B3LYP/6-311++G (3dp, 3df) levels of theory. Transitions between energy levels are analyzed in terms of wavenumber. The rotational constants of the HCl molec...
Show More
