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The studies’ results of the adhesive and the cement-polymer compositions shrinkage phenomena are given. Theoretical approaches are justified when selecting additives to reduce the cement-polymer systems shrinkage deformations. A method for measuring water separation and shrinkage with the DBS device (the soil bucking measuring device), which simulates the modified disperse systems intrinsic deformations processes and of the products based on them, is proposed. The adhesion strength results of at the “stone material-solution” boundary are given. It has been shown that the solutions shrinkage has a significant effect on the adhesive strength.

Nanometre-sized diamond has been found in meteorites 1 , protoplanetary nebulae 2 and interstellar dusts 3 , as well as in residues of detonation 4 and in diamond films 5 , 6 . Remarkably, the size distribution of diamond nanoparticles seems to be peaked around 2–5 nm, and to be largely independent of preparation conditions. We have carried out ab initio calculations of the stability of nanodiamond as a function of surface hydrogen coverage and of size. We have found that at about 3 nm, and for a broad range of pressures and temperatures, particles with bare, reconstructed surfaces become thermodynamically more stable than those with hydrogenated surfaces, thus preventing the formation of larger grains. Our findings provide an explanation of the size distribution of extraterrestrial and of terrestrial nanodiamond found in ultradispersed and ultracrystalline diamond films. They also provide an atomistic structural model of these films, based on the topology and structure of 2–3-nm dimond clusters consisting of a diamond core surrounded by a fullerene-like carbon network 7 .

Inorganic nanoparticles exhibit size-dependent properties that are of interest for applications ranging from biosensing 1 , 2 , 3 , 4 , 5 and catalysis 6 to optics 7 and data storage 8 . They are readily available in a wide variety of discrete compositions and sizes 9 , 10 , 11 , 12 , 13 , 14 . Shape-selective synthesis strategies now also yield shapes other than nanospheres, such as anisotropic metal nanostructures with interesting optical properties 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 . Here we demonstrate that the previously described photoinduced method 23 for converting silver nanospheres into triangular silver nanocrystals—so-called nanoprisms—can be extended to synthesize relatively monodisperse nanoprisms with desired edge lengths in the 30–120 nm range. The particle growth process is controlled using dual-beam illumination of the nanoparticles, and appears to be driven by surface plasmon excitations. We find that, depending on the illumination wavelengths chosen, the plasmon excitations lead either to fusion of nanoprisms in an edge-selective manner or to the growth of the nanoprisms until they reach their light-controlled final size.

An experimental model is suggested for investigating the motion of magnetic dispersions under the action of mechanical and volumetric magnetic surface forces created respectively by a rotating cylinder and by the inhomogeneous field of a transversely polarized cylindrical magnet. Using as an example a single magnetic ball, the characteristic features of motion attributable to the competition among the surface, magnetic, and inertial forces in the ″cylindrical magnet–rotating cylinder–quiescent cylinder″ system have been studied, including the critical frequency of the inertial slipping of dispersion from the rotating surface and the dynamic equilibrium of dispersion under the conditions of competition between the centrifugal slipping and magnetic capture.

The sorption of triterpene saponins is studied on different brands of active carbon under equilibrium conditions. The effect the surface activity of glycosides has on the course of the curves is established. Sorption isotherms are assessed using a formal approach based on selecting the sorption equations (Langmuir, Freundlich, BET, Redlich–Peterson) that describe the obtained dependences as closely as possible. Thermodynamic characteristics of the given process (energy of sorption, enthalpy, and entropy) are calculated using sorption curves in the coordinates of the Langmuir equation.

Interpenetration (catenation) has long been considered a major impediment in the achievement of stable and porous crystalline structures. A strategy for the design of highly porous and structurally stable networks makes use of metal-organic building blocks that can be assembled on a triply periodic P-minimal geometric surface to produce structures that are interpenetrating-more accurately considered as interwoven. We used 4,4′,4″-benzene-1,3,5-triyl-tribenzoic acid (H3BTB), copper(II) nitrate, and N, N′-dimethylformamide (DMF) to prepare Cu3(BTB)2(H2O)3· (DMF)9(H2O)2(MOF-14), whose structure reveals a pair of interwoven metal-organic frameworks that are mutually reinforced. The structure contains remarkably large pores, 16.4 angstroms in diameter, in which voluminous amounts of gases and organic solvents can be reversibly sorbed.

This work presents the results of investigations of the topological characteristics of quartz raw materials of various mineral compositions crushed to the critical state of the dispersed layer under which the shape of the particles and the action of the electrostatic repulsion forces change.

The Himalayan-sourced Ganges-Brahmaputra river system and the deep-sea Bengal Fan represent Earth’s largest sediment-dispersal system. Here we present detrital zircon U-Pb provenance data from Miocene to middle Pleistocene Bengal Fan turbidites, and evaluate the influence of allogenic forcing vs. autogenic processes on signal propagation from the Himalaya to the deep sea. Our data record the strong tectonic and climatic forcing characteristic of the Himalayan system: after up to 2500 km of river transport, and >1400 km of transport by turbidity currents, the U-Pb record faithfully represents Himalayan sources. Moreover, specific U-Pb populations record Miocene integration of the Brahmaputra drainage with the Asian plate, as well as the rapid Plio-Pleistocene incision through, and exhumation of, the eastern Himalayan syntaxis. The record is, however, biased towards glacial periods when rivers were extended across the shelf in response to climate-forced sea-level fall, and discharged directly to slope canyons. Finally, only part of the record represents a Ganges or Brahmaputra provenance end-member, and most samples represent mixing from the two systems. Mixing or the lack thereof likely represents the fingerprint of autogenic delta-plain avulsions, which result in the two rivers delivering sediment separately to a shelf-margin canyon or merging together as they do today.

The necessity of a flow express control of oil dispersed system (ODS) properties, such as crude oil, oil products, water–oil emulsions, and polluted waters, is substantiated. This control is necessary for the production and preparation of oil for transportation through the pipeline and oil refining, oil products, and wastewater treatment systems. A developed automatic measuring complex (AMC) is used to implement the concept of digital oil deposits. The primary measuring device is a relaxometer developed by us based on nuclear (proton) magnetic resonance (PMR). The design and operation algorithm of the AMC and the relaxometer are described. Equations have been developed to determine the ODS characteristics using the measured PMR parameters. This makes it possible to determine the flow rates of crude oil, the concentration of water in the oil, the concentration of asphaltene, resins, and paraffins in the oil, as well as the density, viscosity, and molecular weight of the oil. Additionally, it is possible to determine the dispersed distribution of water droplets in emulsions in oil production and treatment units. Data on this distribution will improve the management of separation processes. It has been established that the implemented control of multiphase ODS using PMR parameters (relaxation times, populations of proton phases, and amplitudes of spin-echo signals) makes it possible, using AMC, to assess the consumption of electricity in technological processes at the digital oil deposits, as well as during the transportation of oil and oil products through pipelines. AMC makes it possible to reduce electrical energy consumption in technological installations and reduce pollution emissions into wastewater. The advantages of using the developed AMC are shown in examples of its application. Such as an assessment of the influence of the gas factor on electricity consumption during oil transportation through pipelines or compensation for the additional moment of resistance on the shaft of the submersible motor, which is caused by surface tension forces at the interface of water droplets in the emulsion.

It is demonstrated that exposing petroleum disperse systems to ultrasound significantly decreases their viscoelastic properties. The operating parameters of exposure of high-viscosity oil to ultrasound were experimentally determined in order to reduce its effective viscosity and pour point. The results of pilot tests of the developed ultrasound module indicate that exposing high-viscosity oil to ultrasound in flow mode can significantly upgrade existing technology for transporting high-viscosity oil.