57 research outputs found

    Determination of the efficiency of wax deposition prevention methods

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    Nozhovka group of oil fields is located in the south of Perm region. Main factors that complicate development of the fields are as follows: low reservoir permeability and temperatures, high water cut, oil of high viscosity with high concentration of paraffins, sulfur and non hydrocarbon components. The analysis of affected wells that represent 67% of total showed that the main cause is wax deposition that leads to early breakdown of pumps, decrease of well productivity and mean time between failures and cleanings. The paper shows coverage of wells experience wax deposition by technologies that prevent it. Input of inhibitors of wax deposition to the well bottom hole is efficient method to prevent wax deposition. The results of oil and wax samples study from Nozhovka fields group showed oil was heavy and highly-viscous. Wax deposition belongs to asphaltene type. The evaluation of inhibitors efficiency was carried with use of statistic criteria of decision. Based on the analysis results SNPH type of mixtures was efficient inhibitors of wax deposition on the fields of Nozhovka group. The disadvantage of used technology is that there is no universal inhibitor of wax deposition for the oil from Nozhovka group of fields, high specific consumption of inhibitors and continuously changing properties of the producing liquid that require continuous tuning of used inhibitors. In order to decrease the consumption for inhibitor protection from wax deposition it is expedient to select new inhibition compositions with demulsifiying properties and field test of unconventional technologies through injection into well bottom hole and borehole

    Intermediate Fusion Approach for Pneumonia Classification on Imbalanced Multimodal Data

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    In medical practice, the primary diagnosis of diseases should be carried out quickly and, if possible, automatically. The processing of multimodal data in medicine has become a ubiquitous technique in the classification, prediction and detection of diseases. Pneumonia is one of the most common lung diseases. In our study, we used chest X-ray images as the first modality and the results of laboratory studies on a patient as the second modality to detect pneumonia. The architecture of the multimodal deep learning model was based on intermediate fusion. The model was trained on balanced and imbalanced data when the presence of pneumonia was determined in 50% and 9% of the total number of cases, respectively. For a more objective evaluation of the results, we compared our model performance with several other open-source models on our data. The experiments demonstrate the high performance of the proposed model for pneumonia detection based on two modalities even in cases of imbalanced classes (up to 96.6%) compared to single-modality models’ results (up to 93.5%). We made several integral estimates of the performance of the proposed model to cover and investigate all aspects of multimodal data and architecture features. There were accuracy, ROC AUC, PR AUC, F1 score, and the Matthews correlation coefficient metrics. Using various metrics, we proved the possibility and meaningfulness of the usage of the proposed model, aiming to properly classify the disease. Experiments showed that the performance of the model trained on imbalanced data was even slightly higher than other models considered.In medical practice, the primary diagnosis of diseases should be carried out quickly and, if possible, automatically. The processing of multimodal data in medicine has become a ubiquitous technique in the classification, prediction and detection of diseases. Pneumonia is one of the most common lung diseases. In our study, we used chest X-ray images as the first modality and the results of laboratory studies on a patient as the second modality to detect pneumonia. The architecture of the multimodal deep learning model was based on intermediate fusion. The model was trained on balanced and imbalanced data when the presence of pneumonia was determined in 50% and 9% of the total number of cases, respectively. For a more objective evaluation of the results, we compared our model performance with several other open-source models on our data. The experiments demonstrate the high performance of the proposed model for pneumonia detection based on two modalities even in cases of imbalanced classes (up to 96.6%) compared to single-modality models’ results (up to 93.5%). We made several integral estimates of the performance of the proposed model to cover and investigate all aspects of multimodal data and architecture features. There were accuracy, ROC AUC, PR AUC, F1 score, and the Matthews correlation coefficient metrics. Using various metrics, we proved the possibility and meaningfulness of the usage of the proposed model, aiming to properly classify the disease. Experiments showed that the performance of the model trained on imbalanced data was even slightly higher than other models considered

    Investigation of the effect of the grain sizes on the dynamic strength of the fine-grained alumina ceramics obtained by Spark Plasma Sintering

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    The results of dynamic strength tests of the alumina ceramics with various grain sizes are presented. The ceramics were obtained by Spark Plasma Sintering (SPS) of industrial submicron and fine Al2O3 powders. The heating up was performed with the rate of 10 oC/min; the grain sizes in the ceramics was controlled by varying the SPS temperature and the heating rate as well as by varying the initial sizes of the Al2O3 particles in the powders. The ceramics had a high density (over 98%) and a uniform fine-grained microstructure (the mean grain sizes varied from 0.8 to 13.4 mkm). The dynamic compressing tests were carried out by modified Kolsky method with using split Hopkinson pressure bar. The tests were performed at room temperature using a 20-mm PG-20 gas gun with the strain rate of ~10^3 s-1. The dependence of the dynamic ultimate strength of alumina on the grain size was found for the first time to have a non-monotonous character (with a maximum). The maximum value of the dynamic ultimate compression strength (SY = 1060 MPa) was provided at the mean grain size of ~2.9-3 mkm. The reduction of SY for alumina in the range of submicron grain sizes was shown to originate from the reduction of the relative density of the ceramics sintered at lower SPS temperatures.Comment: 16 pages, 1 table, 6 figures, 28 reference

    Effect of annealing on the corrosion-fatigue strength and hot salt corrosion resistance of fine-grained titanium near-{\alpha} alloy Ti-5Al-2V obtained by Rotary Swaging

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    The corrosion-fatigue strength in 3% aqueous NaCl solution and the resistance against hot salt corrosion (HSC) of the fine-grained near-a alloy Ti-5Al-2V (Russian analog of Grade 9 titanium alloy with increased aluminum content) has been studied. The properties of the Ti-5Al-2V alloy in the coarse-grained state, in the fine-grained after cold Rotary Swaging (RS), in partly recrystallized state, and in fully recrystallized one have been investigated. The mechanical properties of the alloy were characterized using compression tests and microhardness measurements. The effects of RS and of the annealing temperature and time on the character of corrosion destruction of the surface and on the composition of the products of the HSC were studied. RS was shown to result in an increase in the depth of the intergranular corrosion defects while the recrystallization annealing promotes the increasing of the corrosion resistance of the Ti-5Al-2V titanium alloy. The parameters of the Basquin equation for the corrosion-fatigue curves for the near-a Ti-5Al-2V alloy in the coarse-grained state, in the severely strained one, and after recrystallization annealing were determined for the first time. An effect of nonmonotonous dependencies of the slopes of the corrosion-fatigue curves for the strained near-a Ti-5Al-2V alloy on the recrystallization annealing temperature has been observed.Comment: 46 pages, 1 table, 19 figures, 64 reference

    Scientific justification of the perforation methods for Famennian deposits in the southeast of the Perm Region based on geomechanical modelling

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    The article presents the results of analysing geological structure of the Famennian deposits (Devonian) in the Perm Region. Numerical modelling of the distribution of inhomogeneous stress field near the well was performed for the two considered types of perforation. With regard for the geometry of the forming perforation channels, numerical finite element models of near-wellbore zones were created considering slotted and cumulative perforation. It is ascertained that in the course of slotted perforation, conditions are created for a significant restoration of effective stresses and, as a result, restoration of reservoir rock permeability. Stress recovery area lies near the well within a radius equal to the length of the slots, and depends on the drawdown, with its increase, the area decreases. From the assessment of failure areas, it was found that in case of slotted perforation, the reservoir in near-wellbore zone remains stable, and failure zones can appear only at drawdowns of 10 MPa and more. The opposite situation was recorded for cumulative perforation; failure zones near the holes appear even at a drawdown of 2 MPa. In general, the analysis of results of numerical simulation of the stress state for two simulated types of perforation suggests that slotted perforation is more efficient than cumulative perforation. At the same time, the final conclusion could be drawn after determining the patterns of changes in permeability of the considered rocks under the influence of changing effective stresses and performing calculations of well flow rates after making the considered types of perforation channels

    MORPHOFUNCTIONAL PECULIARITIES OF MUCOSAL IMMUNITY DEPENDING ON METHODS OF OPPORTUNISTIC MICROBIAL INTRODUCTION

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    Immunophenotypic and morphological peculiarities of immune reactions under intranasal, peroral and subcutaneous introduction of multicomponent vaccine Immunovac VP-4 containing a group of opportunistic bacterial antigens were investigated. The investigated preparation was found to cause marked activation of congenital immunity effectors both in parenteral and mucosal immunization. It is manifested in the expression of differential, costimulatory, adhesive molecules on the surface of mononuclear leukocytes in proliferation of key mucosal immunity effectors (γδТ, В1, NK cells), and changes in structure, cellular composition of immunocompetent organs both regional and distant as to the site of introduction. Currently existing data on effects and mechanisms of vaccine and immunomodulator mucosal introduction allows considering the development of mucosal mono- and associated vaccines as the priority direction in modern vaccinology

    Indolyl-Derived 4H-Imidazoles: PASE Synthesis, Molecular Docking and In Vitro Cytotoxicity Assay

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    The strategy of the nucleophilic substitution of hydrogen (SNH) was first applied for the metal-free C-H/C-H coupling reactions of 4H-imidazole 3-oxides with indoles. As a result, a series of novel bifunctional azaheterocyclic derivatives were obtained in yields up to 95%. In silico experiments on the molecular docking were performed to evaluate the binding possibility of the synthesized small azaheterocyclic molecules to the selected biotargets (BACE1, BChE, CK1δ, AChE) associated with the pathogenesis of neurodegenerative diseases. To assess the cytotoxicity for the synthesized compounds, a series of in vitro experiments were also carried out on healthy human embryo kidney cells (HEK-293). The leading compound bearing both 5-phenyl-4H-imidazole and 1-methyl-1H-indole moieties was defined as the prospective molecule possessing the lowest cytotoxicity (IC50 > 300 µM on HEK-293) and the highest binding energy in the protein–ligand complex (AChE, −13.57 kcal/mol). The developed compounds could be of particular interest in medicinal chemistry, particularly in the targeted design of small-molecule candidates for the treatment of neurodegenerative disorders. © 2023 by the authors.Ministry of Education and Science of the Russian Federation, Minobrnauka: 075-15-2022-1118, W03.31.0034; Russian Science Foundation, RSF: 20-73-10077The chemical design, synthesis and characterization of indolyl-derived 4H -imidazoles and in vitro studies were supported by the Russian Science Foundation (Project # 20-73-10077). The in silico studies were supported by the Ministry of Science and Higher Education of the Russian Federation (Ref. # 075-15-2022-1118, dated 29 June 2022). The synthesis of starting 4H -imidazole N -oxide substrates was supported by the Ministry of Science and Higher Education of the Russian Federation (Project # 14.W03.31.0034)

    ВОССТАНОВЛЕНИЕ ФУНКЦИЙ ВНЕШНЕГО ДЫХАНИЯ У ПОСЛЕОПЕРАЦИОННЫХ ПАЦИЕНТОВ С ПОМОЩЬЮ ТЕХНОЛОГИИ БИОУПРАВЛЕНИЯ, ОРГАНИЗОВАННОГО ПО КОНЦЕНТРАЦИИ УГЛЕКИСЛОГО ГАЗА В ВЫДЫХАЕМОМ ВОЗДУХЕ И ЧАСТОТЕ ДЫХАНИЯ

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    The methodical, technical and software realization of the biofeedback of expiration parameters are described. The biofeedback training method based on the breath frequency and CO2  concentration regulation is proposed. Preliminary study was conducted in the group of patients after abdominal surgical. It has been shown that the patients master their skills of CO2  concentration self-regulation. Using biofeedback for the postsurgical rehabilitation facilitates the rapid recovery of the expiration parameters.В статье рассматриваются методические, технические и программные аспекты адаптивного биоуправления, организованного по параметрам внешнего дыхания. Предложена методика БОС-тренинга, основанная на регуляции частоты дыхания и содержания углекислого газа в выдыхаемом воздухе. Проведены предварительные исследования в группе пациентов после абдоминальной хирургической операции. Показано, что пациенты осваивают навыки произвольной регуляции содержания углекислого газа в выдыхаемом воздухе. Был сделал вывод о том, что применение БОС-тренинга в послеоперационном периоде способствует быстрому восстановлению параметров внешнего дыхания

    CK2 Inhibition and Antitumor Activity of 4,7-Dihydro-6-nitroazolo[1,5-a]pyrimidines

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    Today, cancer is one of the most widespread and dangerous human diseases with a high mortality rate. Nevertheless, the search and application of new low-toxic and effective drugs, combined with the timely diagnosis of diseases, makes it possible to cure most types of tumors at an early stage. In this work, the range of new polysubstituted 4,7-dihydro-6-nitroazolo[1,5-a]pyrimidines was extended. The structure of all the obtained compounds was confirmed by the data of 1H, 13C NMR spectroscopy, IR spectroscopy, and elemental analysis. These compounds were evaluated against human recombinant CK2 using the ADP-GloTM assay. In addition, the IC50 parameters were calculated based on the results of the MTT test against glioblastoma (A-172), embryonic rhabdomyosarcoma (Rd), osteosarcoma (Hos), and human embryonic kidney (Hek-293) cells. Compounds 5f, 5h, and 5k showed a CK2 inhibitory activity close to the reference molecule (staurosporine). The most potential compound in the MTT test was 5m with an IC50 from 13 to 27 µM. Thus, our results demonstrate that 4,7-dihydro-6-nitroazolo[1,5-a]pyrimidines are promising for further investigation of their antitumor properties. © 2022 by the authors.Ministry of Education and Science of the Russian Federation, Minobrnauka: FEUZ-2020–0058, H687.42B.223/20This work was financially supported by the Ministry of Science and Higher Education of the Russian Federation, State Contract № FEUZ-2020–0058 (H687.42B.223/20)
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