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Chondrules are tiny particles that occur in stony meteorites and are considered as the building blocks of early asteroids and planets. It is believed that they were formed by the fast heating of the dust in the solar nebula. To date, there is no lab-scale experimental study of the formation of chondrules from the initial gas phase precursors following fast heating and crystallisation. The motivation of this work is a pre-trial study of the formation of chnodrule-like particles. The formation of meteorites in the space environment is associated with the aggregation of small particles or molecular clouds under the influence of shock waves or high-energy gas discharges in the solar nebula. In this work, the properties of product formation at the nanoscale-level were investigated using different feedstock materials which are the dominant elements in the meteorite. The structural and morphological properties of the synthesised Si-Fe nanomaterials were analysed by scanning/transmission electron microscopy (SEM/TEM), and chemical composition was analysed by X-ray energy-dispersive spectroscopy (EDS). The identification of crystalline phases was carried out by X-ray diffraction (XRD), whereas the presence of an Fe-Si system in the synthesised particles was demonstrated by Mössbauer spectroscopy. The obtained materials were exposed to the relatively high-energy pulsed plasma beam on the substrate with the aim to emulate the possible fast heating and melting of the formed nanoparticles. The formation steps of growing synthetic (engineered) chondro-like particles and nanostructures in laboratory conditions is discussed. [ABSTRACT FROM AUTHOR]

Silicon Oxide nanoparticle (SiO2-NP) with appropriate surface functionalization has tremendous potential in enhanced oil recovery (EOR) via wettability alternation, interfacial tension reduction, disjoining pressure enhancement, electric charge modification, etc. Prior to the application of SiO2 to EOR, an effective functionalization and an accurate characterization of the surface properties are indispensable. Though many experimental works have been performed in this area, a systematic review is still lacking. Therefore, a review of the above content is presented. Current research gaps are identified, and future outlooks are indicated. This review provides guidance for SiO2-NP surface functionalization, characterization, and evaluation. [ABSTRACT FROM AUTHOR]

Zinc oxide (ZnO) and materials based on it are often used to create battery-type supercapacitor electrodes and are considered as promising materials for hybrid asymmetric supercapacitors. However, when creating such electrodes, it is necessary to take into account the instability and degradation of zinc oxide in aggressive environments with a non-neutral pH. To the best of our knowledge, studies of the changes in the properties of ZnO-containing electrodes in alkaline electrolytes have not been carried out. In this work, changes in the structure and properties of these electrodes under alkaline treatment were investigated using the example of ZnO-containing composites, which are often used for the manufacturing of supercapacitor electrodes. Supercapacitor electrodes made of two materials containing ZnO were studied: (i) a heterogeneous ZnO-Co3O4 system, and (ii) a hexagonal h-Zn-Co-O solid solution. A comparison was made between the structure and properties of these materials before and after in situ electrochemical oxidation in the process of measuring cyclic voltammetry and galvanostatic charge/discharge. It has been shown that the structure of both nanoparticles of the heterogeneous ZnO-Co3O4 system and the h-Zn-Co-O solid solution changes due to the dissolution of ZnO in the alkaline electrolyte 3.5 M KOH, with the short-term alkaline treatment producing cobalt and zinc hydroxides, and long-term exposure leading to electrochemical cyclic oxidation–reduction, forming cobalt oxide Co3O4. Since the resulting cobalt oxide nanoparticles are immobilized in the electrode structure, a considerable specific capacity of 446 F g−1 or 74.4 mA h g−1 is achieved at a mass loading of 0.0105 g. The fabricated hybrid capacitor showed a good electrochemical performance, with a series resistance of 0.2 Ohm and a capacitance retention of 87% after 10,000 cycles. [ABSTRACT FROM AUTHOR]

The interaction between nanoparticles and cationic surfactants is an exciting and emerging field in interfacial science. This area of research holds significant promise, linking fundamental principles to practical applications in a variety of industries, including chemical processes, biomedical applications and the petroleum industry. This study explores the interaction between dodecyltrimethylammonium bromide (DoTAB) and silica (SiO2) nanoparticles, investigating their influence on dynamic interfacial properties and foam characteristics. Through equilibrium and dynamic surface tension measurements, along with examining the dilational visco-elasticity behavior, this research reveals the complex surface behavior of DoTAB/SiO2 mixtures compared to individual surfactant solutions. The foamability and stability experiments indicate that the addition of SiO2 significantly improves the foam stability. Notably, stable foams are achieved at low SiO2 concentrations, suggesting a cost-effective approach to enhancing the foam stability. This study identifies the optimal stability conditions for 12 mM DoTAB solutions, emphasizing the crucial role of the critical aggregation concentration region. These findings offer valuable insights for designing surfactant-nanoparticle formulations to enhance foam performance in various industrial applications. [ABSTRACT FROM AUTHOR]

This paper deals with the potential of aggregates of surfactant and SiO2 nanoparticles as foam stabilizers for practical applications. The effects of different chain lengths and concentrations of the cationic surfactant C n TAB on the performance of C n TAB–SiO2 nanofluids are examined to gain a comprehensive understanding of their ability to stabilize foam. The results indicate enhanced foam stability in the presence of SiO2 nanoparticles. These findings help to better understand foam stabilization and its potential in various industrial applications such as enhanced oil recovery and foam-based separation processes. [ABSTRACT FROM AUTHOR]

In present work, thermodynamic expressions were obtained through potentials that took into consideration long-range many-particle screening effects as well as short-range quantum-mechanical effects and radial distribution functions (RDFs). Stopping power of the projectile ions in dense, non-isothermal plasma was considered. One of the important values that describe the stopping power of the ions in plasma is the Coulomb logarithm. We investigated the stopping power of ions in inertial confinement fusion (ICF) plasma and other energetic characteristics of fuel. Calculations of ions energy losses in the plasma for different values of the temperature and plasma density were carried out. A comparison of the calculated data of ion stopping power and energy deposition with experimental and theoretical results of other authors was also performed.

This work presents experimental results on the synthesis of сarbon nanowalls (CNWs) with predefined morphology on the surface of the nanoporous alumina membrane using two different methods, namely radio-frequency plasma-enhanced chemical vapor deposition (RF-PECVD) and radical-injection (RI)-PECVD. Obtained samples were characterized by the methods of scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Raman spectroscopy. From the microstructure analyses of CNWs, it has been observed that there is a time dependence on the reproducibility of membrane morphology by CNWs. At the early stage of nanowalls growth, nanowalls prefer to grow around the edges of nanopores and continue to grow vertically with time. In RF-PECVD, the nanopores' size begins to shrink drastically and pores are completely covered by secondary flake-like nanowalls after 25 minutes of growth. In the case of CNWs grown using RI-PECVD, nanowalls are more vertical and self-supported. This is because of the rapid and sustained production of hydrogen radicals that prevent the secondary growth of carbon nanowalls. In addition, the influence of pores diameter and membrane thickness on the growth of RI-PECVD CNWs was revealed. [ABSTRACT FROM AUTHOR]

In this paper we considered three methods of carbon nanotube (CNT) synthesis: chemical vapor deposition in a fixed and fluidized bed rector, and pyrolysis of nebulized solutions of ferrocene in carbon precursor solvents. The latter method has a high CNT yield and allows multiwalled (MWCNTs) as well as single-walled nanotubes (SWCNTs) to be obtained. The samples were analyzed by scanning electron microscopy and Raman spectroscopy. The optimal technological conditions giving a maximum yield of CNTs were studied. A CNT-copper composite was obtained by electroplating or by electroless Cu deposition on the SWCNT layer. MWCNTs were grown on silica fibers and electrical properties of the composite were measured. It was found that electrical resistance of the composite is pressure dependent and its conductivity can be easily varied changing the conditions of synthesis. PACS Nos.: 81.15.Gh, 61.48.De. Nous comparons ici trois methodes pour synthetiser des nanotubes de carbone (CNT) : le depot chimique en phase vapeur dans un reacteur a lit, soit fixe, soit fluidise et la pyrolyse de solutions nebulisees de ferrocene dans un solvant precurseur de carbone. Cette derniere methode a une production elevee de CNT et permet d'obtenir des nanotubes simples (SWCNT) et multicouches (MWCNT). Nous analysons les echantillons obtenus par microscopie electronique a balayage et par spectroscopie Raman. Nous recherchons les conditions techniques optimales pour produire un maximum de nanotubes. Nous pouvons obtenir des nanotubes composes carbone-cuivre, soit par electro-plaquage, soit par deposition chimique sur la couche de SWCNT. Les MWCNT croissent sur des fibres de silice et nous mesurons les proprietes electriques des composites. Nous trouvons que la resistance electrique du composite depend de la pression et cette conductivite varie facilement avec les conditions de synthese. [Traduit par la Redaction], Introduction Carbon nanotubes (CNTs) have unique electronic, thermal, and mechanical properties, which makes them promising for numerous applications. CNTs can be used in many materials and devices, such as field [...]