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Depending on reservoir conditions, composition of reservoir oil and gas agent, various modes of oil displacement by gas can be implemented in reservoir conditions. The most preferable mode from the standpoint of the completeness of oil recovery is the mode of miscible displacement of oil by gas. The main parameter indicating the achievement of the miscible displacement mode is the minimum miscibility pressure. The most popular and reliable laboratory method for determining the minimum mixing pressure is the slim-tube method. The results of laboratory studies performed to determine the value of the minimum miscibility pressure of reservoir oil from the Tolumskoye field and associated petroleum gas of the Semividovskaya group of fields and also to determine the mode of oil displacement by associated petroleum gas are presented. To determine the parameters of reservoir oil and change its properties at various molar concentrations, the standard PVT research technique was used. To determine the minimum miscibility pressure, the slim-tube technique was used. To assess the mechanism of miscibility process development, chromatographic analysis of the sampled gas composition and visual analysis of the phase fluids behavior by means of a visual cell were additionally performed. Two series of filtration experiments were performed to displace the recombined oil model of the Tolumskoye field by the model of associated petroleum gas from the Semividovskaya group of fields on slim models. According to the obtained dependence of the oil displacement coefficient on pressure, when oil from the Tolumskoye field was displaced by associated petroleum gas of the Semividovskaya group of fields, the minimum miscibility pressure would be 14.8 MPa. Based on the criteria for determining the mixing mode, as a result of generalization and comprehensive analysis of the research results, it was found that for the conditions of the Tolumskoye field, the mode of oil displacement by associated petroleum gas of the Semividovskaya group of fields was the mode of the developed multi-contact miscible displacement (the mechanism of condensation of solvent components into the oil phase).

Currently, thermal methods of enhanced oil recovery are based on the use of heat transfer mediums (steam, hot water) and in-situ combustion, which are the most efficient methods in the development of heavy oil reservoirs. In this study, experimental and numerical modeling was carried out to estimate the efficiency of hot water injection to engage in the active development of high-viscosity oil reserves in a deep carbonate reservoir. There is a limited amount of published experimental studies on carbonates, in comparison with sandstones, shale, or oil sands. Oil-bearing formations at depths of 1100–1500 m require technology that can achieve sufficiently high fluid temperature (250–300 °C) in the bottom-hole zone to be successful. The performance of the implemented technique on a field greatly depends on the quality of the experimental data and numerical simulation. Particularly, the hydrodynamic model, reaction kinetics, and operational parameters are crucial parameters for future upscaling. The hot water injection experiment was conducted using a medium pressure combustion tube assembly on the reservoir rock model made of consolidated carbonate samples. Moreover, a new numerical model was constructed to simulate the experiment with a reproduction of the fluid models, properties of the oil and rock samples, and full geometry of the core holders where chemical interactions occur. What makes this model authentic is the calibration of reaction kinetics called “aquathermolysis” to hot water injection process, which replicate the most prevalent thermal process during the interaction of hot water and hydrocarbons. A close correlation between experimental and numerical results was obtained in terms of cumulative water and oil recovery and temperature profiles. The developed numerical model reflects the dynamics of oil displacement at different rates of water injection. According to experimental and numerical simulations, thermal effects reduce viscosity with a proportionate increase in oil recovery. The achieved recovery factor for the experiment was 63%. Lastly, a good match of cumulative gases (CH4, H2, H2S, CO2, and HMWG) was obtained for the hot water injection experiment. Adapted fluid model, relative permeability, kinetic model, and operational parameters are necessary for the upscaling to the field. The improved efficiency of oil displacement at this site is confirmed by numerical simulation.

We present our results on developing a diagnostic complex for high-precision characterization of the parameters of laser-fusion microobjects, such as microspheres and cryogenic targets (the microobject size is 1–2 mm). The complex operates based on the principle of tomography. The complex consists of (a) the scanning system providing a set of shadow projections of a microobject in the visible range of radiation and (b) specially developed software for 3D reconstruction of the microobject from the set of projections. The spatial resolution of the optical system is 1 µm for a probing-radiation wavelength of 490 nm. The distinctive features of the diagnostic complex are (1) operation with both free-standing and mounted targets and (2) the possibility of scanning the targets from room to cryogenic temperatures. The operation of the complex was demonstrated in the reconstruction of polystyrene microspheres by a large set (80–90) of shadow projections at room and cryogenic temperatures.

In conventional inertial confinement fusion (ICF) a high power laser system is used to compress a cryogenic target and create energy. One of the challenges for ICF cryogenics is producing a homogen...

The target factory of an Inertial Fusion Energy (IFE) power plant (or reactor) must supply the targets with a rate of 1-10 Hz including their injection and transport through the chamber. HiPER is a proposed European High Power laser Energy Research facility dedicated to demonstrate the feasibility of laser driven fusion for IFE reactor. The work of HiPER facility requires formation & delivery of cryogenic free-standing targets with a rate of more than 1 Hz. To meet these requirements, an approach to fuel layering based on conduction cooling of a batch of moving spherical targets has been developed at the Lebedev Physical Institute (LPI). The approach demands to use free-standing targets in each production step: fuel filling, fuel layering, target characterization and injection. In this report, the expert results on the development of a specialized layering module prototype for a high reprate FST formation of HiPER cryogenic targets are presented.

It is recommended to use the capacity of pathogenic staphylococci to be lysed by polyvalent therapeutic staphylococcal bacteriophage in the capacity of an additional simple and accessible criterion of staphylococcus pathogenicity. Of 147 strains of the pathogenic plasmacoagulating staphylococci 101 were lysed by the phage and of 166 nonplasmocoagulating nonpathogenic strains--only 6. This test correlated with the other signs of staphylococcus (lecithinase and hemolytic activity). The simplicity and sufficient specificity of this test permits to use it in any practical laboratory. Polyvalent diagnostic phage can be used on the basis of therapeutic bacteriophage by its additional adaptation to the pathogenic strains of staphylococcus.

One hundred and twenty four patients (males - 102, females - 22) aged 20-59 years were investigated. The first group comprised patients (72) suffering ulcerous disease of the stomach and duodenum, the second (43) - patients investigated in the immediate postoperative period, the third (50) - patients investigated in later postoperative terms. The routine cholegraphy was performed after a standard technic. Structual alterations and functional disorders in the gallbladder and bile ducts concomitant with gastroduodenal ulcerous disease are described. The results of Billroth-I and Billroth-II gastrectomies are compared, and it is condluded that the Billroth-I gastric resection can be considered the operation of choice, since it is not accompaned with any serious changes in the structure and function of biliary passages.