The structure of liquid aluminosilicate under AI2O3 content: simplexes and shell core analyses

The structural properties of xAl2O3(1-x)SiO2 liquid systems have been investi-gated by molecular dynamics simulation in a wide range of compositions, x = 0.05–0.7 at 3000 K. The structure of liquid aluminosilicate system is clarified by analyzing the simplex and shell-core. The simulated results showed that the liquid consists of a large quantity of void-simplex, O-simplex, T-simplex, and SC-particle. Our simulation reveals that the densification of the liquid is due to the fact that the number of large simplexes and the radii of simplexes and SC-particles decrease. Besides, results also indicated that the distribution of cations in the liquid is not uniform.

Liquid water simulation using hydrogen bond corrected SCAN and neural network potentials.

Accurately reproducing the structure of liquid water with ab initio molecular dynamics (AIMD) simulation is a crucial first step on the path towards accurately predicting the properties of liquid solutions without relying on experiment. Density functional theory (DFT) is normally used to approximate the forces in these simulations. However, no DFT functional has been shown to give an entirely satisfactory description of the structure of liquid water. Here, I propose a simple correction to the strongly constrained and appropriately normalised (SCAN) DFT functional, that corrects the strength of the hydrogen bonding interaction with a simple exponential potential fitted to dimer energy calculations. The resulting SCAN-CH functional provides an excellent description of the structure of liquid water. Long time scale NPT simulations are enabled by the use of neural network potentials, which demonstrate that the simulations are well converged and that the density of water is also more accurately reproduced with this method.

The Anomalies and Local Structure of Liquid Water from Many-Body Molecular Dynamics Simulations

For the last 50 years, researchers have sought molecular models that can accurately reproduce water’s microscopic structure and thermophysical properties across broad ranges of its complex phase diagram. Herein, molecular dynamics simulations with the many-body MB-pol model are performed to monitor the thermodynamic response functions and local structure of liquid water from the boiling point down to deeply supercooled temperatures at ambient pressure. The isothermal compressibility and isobaric heat capacity show maxima at ~223 K, in excellent agreement with recent experiments, and the liquid density exhibits a minimum at ~208 K. Furthermore, a local tetrahedral arrangement, where each water molecule accepts and donates two hydrogen bonds, is the most probable hydrogen-bonding topology at all temperatures. This work suggests that MB-pol may provide predictive capability for studies of liquid water’s physical properties across broad ranges of thermodynamic states.

ALTERNATIVE OPTIONS FOR THE PLACEMENT OF ASSETS OF THE UNIFIED ACCUMULATIVE PENSION FUND

In this situation, the peculiarity of managing pension assets is that there are certain requirements for the structure of the investment portfolio, that is, the introduction of preliminary restrictions on the upper share of various categories of instruments in the investment portfolio. They are: by assets, by risk, by concentration of ownership, by issuer and by type of securities. Therefore, in the process of forming a portfolio of assets (shares), assets with the least volatility are selected, i.e. the initial goal is to preserve assets, then profitability. In this regard, investment portfolio managers need to create a structure of liquid financial instruments that can be converted into cash in a very short period of time and receive a stable income with a reasonable level of risk, and make the right decision, carefully comparing them with alternative financial instruments. ... The effectiveness of such strategies often depends on the ability to prioritize investment activities and combine objectives and core principles. The goal is to ensure the safety of investments.

RESEARCH OF THE INFLUENCE OF LEALED TECHNICAL LIGNOSULPHANATES ON THE PHYSICAL-MECHANICAL AND TECHNOLOGICAL PROPERTIES OF LIQUID-GLASS MIXTURES

The paper presents the results of a study of the effect of technical alkalized lignosulfonates on the physicomechanical and technological properties of liquid glass mixtures. As a result of the study, a composition was selected that achieved the lowest residual strength. Using a two-beam scanning electron microscope "Versa 3D", the structure of liquid glass films on a refractory quartz filler is examined with the aim of defects that provide a decrease in residual strength.

Optical Response Associated with the Orientation and Structure of Liquid Crystals with Respect to Phosphatidylcholine Concentration

Based on the anchoring effect due to the self-assembling behavior of the phospholipid molecules at the interface between the liquid crystal and water phases on the orientation of liquid crystals, the optical response associated with the orientation and structure of liquid crystals with respect to the concentration of 1,2-didodecanoyl-sn-glycero-3-phosphocholine solution has been investigated. The optical response owing to changes in the orientation and structure of the mixed cholesteric liquid crystals with respect to the change in the concentration of phosphatidylcholine has been obtained. Moreover, the feasibility of using as-prepared mixed cholesteric liquid crystals to measure the phosphatidylcholine concentration has been verified. A methodology to measure the reflectance spectrum by using mixed cholesteric liquid crystals to sensitize the phosphatidylcholine concentration has been further realized. The sensitization effect of the mixed cholesteric liquid crystals on the measurement of phosphatidylcholine concentration was also verified.