In Memory of George A. Martynov

Provided information about the deceased Georgy Aleksandrovich Martynov - Doctor of Physical and Mathematical Sciences, Professor, Chief Researcher of the Laboratory of Surface Forces of the A.N. Frumkin Institute of Physical Chemistry and Electrochemistry of the Russian Academy of Sciences, a prominent specialist in the field of the theory of liquid state and surface phenomena: basic biographical data, training at the Faculty of Physics of Lomonosov Moscow State University, work at the Institute of Building Physics, defense of candidate (technical) and doctoral (physical and mathematical) dissertations, authorship of more than two hundred scientific papers, three monographs, membership in academic councils, participation and organization of Russian and international conferences and seminars, editorial staff in scientific journals, leadership of doctoral and master's theses.

Propulsion performances study for a chemical tank

The design of a propulsion system for each ship must take into consideration a large number of factors. Some important factors that will lead to obtaining an efficient propulsion system are: the integration of a large number of elements in a functional space, selection of suitable components, the efficiency assessment taking into account functional safety and comfort criteria for crew and passengers. Considering the factors listed above, the analysis and design of the propulsion system for a chemical tank was performed. To choose the optimal components, the propulsion performance for this ship was analysed using 4 different engines. The operation of the propeller behind the ship has an effect on both the structure of the ship and the navigation conditions of the crew on board. Ttherefore, in the last part of the paper will be presented the effect of the operation of the propeller chosen for the chemical tank. In this sense, the surface forces induced by the propeller that appear in the stern vault will also be a center of interest in this work.

Use of new similarities Bl and Blturb. to optimize the calculation and selection of heat exchange equipment for working with nanofluid coolants

The problem of correct, exact calculation and selection of the optimal heat exchange equipment at use in it of nanoliquid heat carriers was investigated in the work. Classical numerical equations, which are widely used in the calculation and selection of heat exchangers with nanofluids, especially at temperatures above 50 °C, give an error of (15–20) % or more. This leads to the fact that the selected heat exchange equipment may not work efficiently with excessive consumption of thermal energy. A new approach to heat transfer processes is considered, taking into account the theory of J. Businesque, which gives an idea of turbulent viscosity and thermal conductivity, as well as comparing the resistance of the coolant flow to the nanoparticle with surface forces and considering turbulent fluid as Newtonian. It is shown that the consideration of the behavior of a nanoparticle in a turbulent liquid coolant without taking into account surface forces is inaccurate and erroneous. The physical content of the previously obtained new numbers of similarity Bl and Blturb is considered and the possibility of their effective application in the new numerical equation obtained by us for the calculation of heat exchangers using nanofluid coolants is shown. The existing express method of estimating the efficiency of nanorluids use in heat exchangers on the basis of classical numerical equations is analyzed and a new express method on the basis of a new numerical equation and new numbers of similarity Bl and Blturb is proposed. The proposed express calculation method shows that a mixture of H2O + EG (60:40) improves the heat transfer properties of water by + 12.86 %, and a mixture of (H2O + EG (60:40) + 1.5 % TiO2) and (milk) + 0.5 % pumpkin seed oil) – by +16.75 %, which corresponds to the experiments and our calculations, and the known express method based on classical numerical equations shows a deterioration of – 4.5 % and, accordingly, by – 1.2 %. An example of calculating the optimal shell-and-tube heat exchanger according to the new algorithm when heating milk with hot water with the addition of mixtures (H2O + EG (60:40) + 1.5 % TiO2) and accordingly (milk + 0.5 % pumpkin seed oil) fully confirms the correctness of the new express –method.

Preliminary results on the simulation of the 1999 Orissa super cyclone using a GCM with a new boundary layer code

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Glycosaminoglycans and glycoproteins influence the elastic response of synovial fluid nanofilms on model oxide surfaces

Synovial fluid (SF) is the natural lubricant found in articulated joints, providing unique cartilage surface protecting films under confinement and relative motion. While it is known that the synergistic interactions of the macromolecular constituents provide its unique load-bearing and tribological performance, it is not fully understood how two of the main constituents, glycosaminoglycans (GAGs) and glycoproteins, regulate the formation and mechanics of robust load-bearing films. Here, we present evidence that the load-bearing capabilities, rather than the tribological performance, of the formed SF films depend strongly on its components' integrity. For this purpose, we used a combination of enzymatic treatments, quartz crystal microbalance with dissipation (QCM-D) and the surface forces apparatus (SFA) to characterize the formation and load-bearing capabilities of SF films on model oxide (i.e., silicates) surfaces. We find that, upon cleavage of proteins, the elasticity of the films is reduced and that cleaving GAGs results in irreversible (plastic) molecular re-arrangements of the film constituents when subjected to confinement. Understanding thin film mechanics of SF can provide insight into the progression of diseases, such as arthritis, but may also be applicable to the development of new implant surface treatments or new biomimetic lubricants.