Исследование образования и уровня осаждения неорганических солей в процессе добычи нефти и газа

Солевое осаждение вызывает множество трудностей в процессе добычи нефти и газа, особенно в шахтах с использованием впрыска воды для поддержания давления в резервуаре. Неорганические карбонатные и сульфатные соли (такие как СаСО[3], CaSO[4], BaSO[4]) могут осаждаться в резервуарах и горном оборудовании из-за изменений температурных условий давления и химического равновесия в процессе эксплуатации. Статья является результатом изучения механизмов формирования и оценки способов образования и осаждения неорганических осадков в процессе разведки нефти и газа для обеспечения безопасной и эффективной эксплуатации системы

Low-density series expansions for directed percolation I: A new efficient algorithm with applications to the square lattice

A new algorithm for the derivation of low-density series for percolation on directed lattices is introduced and applied to the square lattice bond and site problems. Numerical evidence shows that the computational complexity grows exponentially, but with a growth factor \lambda < \protect{\sqrt[8]{2}}, which is much smaller than the growth factor \lambda = \protect{\sqrt[4]{2}} of the previous best algorithm. For bond (site) percolation on the directed square lattice the series has been extended to order 171 (158). Analysis of the series yields sharper estimates of the critical points and exponents.Comment: 20 pages, 8 figures (3 of them > 1Mb

True Lumen Stabilization to Overcome Malperfusion in Acute Type I Aortic Dissection.

Acute type I aortic dissection (AD) complicated by true lumen (TL) collapse and malperfusion downstream is associated with devastating prognosis. The study reports an institutional mid-term experience with TL stabilization by uncovered stents to restore perfusion as a supplement to proximal thoracic aortic surgery. Between January 2007 and May 2017, 181 out of 270 acute type A AD patients were operated on type I AD. Eighteen uncovered stents (10%) were used to expand the aortic TL in presence of visceral and/or peripheral malperfusion. The procedures took place in a hybrid operating room and were combined with proximal aortic surgery. During follow-up (mean ± standard deviation 3.44 ± 2.1 years), the fate of AD was evaluated by computed tomography. Indication for TL stenting included visceral (44%) or peripheral malperfusion (11%) or both (45%). Stenting of aortic branches followed in 33%. All patients underwent proximal repair and were combined with frozen elephant trunk (67%) or retrograde descending aorta stent grafting (11%). Thirty-day mortality was 16.7%. Two-year survival was 71.8%. The false lumen around the uncovered stents remained patent in 89% and the aortic diameter increased 0.1 cm/y. No intimal rupture or occlusion of arteries occurred. In 1 patient, the stented aortic lumen was visualized after 6.3 years and neointima ingrowth covering the nitinol frame was found. In acute type I AD, combined endovascular-surgical procedures in a hybrid operation room setting can be used safely to resolve distal malperfusion. Encapsulation of uncovered stents within the intimal wall provides a stable fundament for endovascular techniques to close entry tears and false lumen

Мониторинг и оптимизация технологических параметров работы скважин, оборудованных установкой электроцентробежных насосов на нефтяном месторождении "Х" (Томская область)

Цель работы – анализ технологической и экономической эффективности применения режима периодического кратковременного включения, а также разработка рекомендаций по времени цикла работы скважины и подбору погружного оборудования на примере Х нефтяного месторождения.The purpose of the work is the analysis of the technological and economic efficiency of the use of the regime of periodic short-term switching on, as well as the development of recommendations for the well cycle time and selection of the submersible equipment using the example of the X oil field

ИСТОРИЯ ІІ МИРОВОЙ: МЕЖДУ СКИЛЛОЙ РЕВИЗИОНИЗМА И ХАРИБДОЙ СТЕРЕОТИПОВ, В ПЛЕНУ АКТУАЛЬНОСТИ

В статті аналізується висвітлення в сучасній історіографії пострадянських країн низки проблемісторії ІІСвітової війни, насамперед концепції ревізіоністського характеру, та дається оцінка їхньої обґрунтованості.This article analyzes coverage of contemporary historiography of post-Soviet countries, a number of problems in the history ofWorldWar II, especially the concept of a revisionist nature, and assesses their validity

Оценка работы компактных канализационных очистных сооружений

Статья посвящена проблемам заводских локальных очистных сооружений.The article is devoted to problems of factory local treatment facilities

Proteomics : A Tool to Study Platelet Function

Acknowledgments: Authors acknowledge Laxmikanth Kollipara for the critical review and Julia Lill for support with figures preparation. The Figure 2 was created in Biorender.Peer reviewedPublisher PD

PROXIMITY TO COVID-19 ON MENTAL HEALTH SYMPTOMS AMONG HOSPITAL MEDICAL STAFF

Background: Exposure to patients with COVID-19 can have a significant impact on mental health of hospital medical staff. The aim of this study was to examine the influence of proximity to patients with COVID-19 considering occupational position and gender on the mental health of hospital staff. Subjects and methods: N=78 participants were included in the study, with n=40 of them with direct contact to patients with COVID-19 (51%); eight had contact with patients suspected of having COVID-19 (10%), and n=30 with no direct contact to people with COVID-19 (39%). Results: Multinomial regression analyses showed that proximity had a negative (inverse) influence on avoidance behaviour as part of PTSD, physical symptoms, somatization, compulsiveness and anger expression-in as tendency to suppress anger. In addition, there was a significant impact of the female gender on increased physical symptoms, while age, work experience and occupation had no further influence. Conclusions: These results that hospital medical staff is less psychologically stressed when closer to COVID-19 patients are inconsistent with previous studies. Self-efficacy and locus of control in these situations are relevant for processing the trauma. In summary, perception of personal risk is essential. Proximity is believed to be a proxy variable for personal risk perception. As a synopsis of these results, regular briefings of the hospital staff are recommended to prevent psychological impairment. They should contain specific information about conditions in the affected wards and the risk of infection, which could help reduce risk perception of medical personnel