bluuebunny/crossref_metadata_2025 huggingface dataset:
Elemental Micro-Characteristic, Thermogravimetric, and FTIR Study of Green Sand(Poly Lactic Acid) for Replacement of Fine Aggregate in Concrete Mix
Authors: PATIL ARUN Y. , Banapurmath N. R. , E P Sumukh , Chitwadagi Manojkumar , Khan T.M. Yunus , Badruddin Irfan Anjum , Kamangar Sarfaraz
Published: September 2020

Poly lactic acid (PLA) has made inroads for commercial market segment with lot many unique characteristics such as tenacity, low flame rate, moisture regain percentage, loss of ignition percentage, heat of combustion, UV resistance, Elastic recovery and higher melting point allowed it to be the fastest moving material in today's commercial market. An attempt has been made to test the feasibility and biocompatibility aspect of PLA with cement mix. The basic strength and physical test results were carried out and published in an article, to the continuation of the work, micro-structural study was conducted to evaluate the elemental characteristics. Thermo gravimetric analysis revealed that PLA either in granular form or filament will hold good for the inclusion into construction applications, provided degradation aspects are to be looked out for improvisation. From DSC it was found that PLA in filament form is the best inclusion material for construction application, however the tenacity of fibers has to checked, as currently available filaments in market does not have high tenacity value. From EDX reports, 30% inclusion of PLA as replacement for fine aggregate has constituent members as Calcium carbonate(CaCO3), Silica(SiO2) and Wollastonite (CaK) resulted in best composition among the rest. FESEM images revealed that, proper gradation in size, rough surface of PLA granular form or filament form will definitely enhance the mechanical/physical or even chemical behavior of PLA.
Geometric Aspects of the Isentropic Liquid Dynamics and Vorticity Invariants
Authors: Balinsky Alexander A. , Blackmore Denis , Kycia Radosław , Prykarpatski Anatolij K.
Published: September 2020

We review a modern differential geometric description of the fluid isotropic motion and featuring it the diffeomorphism group structure, modelling the related dynamics, as well as its compatibility with the quasi-stationary thermodynamical constraints. There is analyzed the adiabatic liquid dynamics, within which, following the general approach, there is explained in detail, the nature of the related Poissonian structure on the fluid motion phase space, as a semidirect Banach groups product, and a natural reduction of the canonical symplectic structure on its cotangent space to the classical Lie-Poisson bracket on the adjoint space to the corresponding semidirect Lie algebras product. We also present a modification of the Hamiltonian analysis in case of the isotermal liquid dynamics. We study the differential-geometric structure of the adiabatic magneto-hydrodynamic superfluid phase space and its related motion within the Hamiltonian analysis and invariant theory. In particular, we construct an infinite hierarchies of different kinds of integral magneto-hydrodynamic invariants, generalizing those before constructed in the literature, and analyze their differential-geometric origins. A charged liquid dynamics on the phase space invariant with respect to an abelian gauge group transformation is also investigated, some generalization of the canonical Lie-Poisson type bracket is obtained.
Diurnal Pine Bark Structure Dynamics Affect Properties Relevant to Firebrand Generation
Authors: Pokswinski Scott , Gallagher Michael R. , Skowronski Nicholas S. , Loudermilk E. Louise , O'Brien Joseph J. , Hiers J. Kevin
Published: September 2020

Firebrands are an important agent of wildfire spread and structure fire ignitions at the wildland urban interface. Bark flake morphology has been highlighted as an important, yet poorly characterized factor in firebrand generation, transport, deposition, and ignition of unburned material. Using pine species where bark flakes are the documented source of embers, we conducted experiments to investigate how bark structure changes in response to diurnal drying. Over a 3-day period in a longleaf pine (Pinus palustris Mill.) stand in Florida, we recorded changes in temperature, moisture content and structure of bark across different facing aspects of mature pine trees to examine the effects of varying solar exposure on bark moisture. We further compared results to bark drying in a pitch pine (Pinus rigida Mill.) plantation in New Jersey. Under all conditions, bark peeled and lifted away from the tree trunk over the study periods. Tree bole aspect and the time of day interacted to significantly affect bark peeling. General temperature increases and moisture content decreases were significantly different between east and west aspects in pitch pine, and with time of day and aspect in longleaf pine. These results illustrate that bark moisture and flakiness is highly dynamic on short time scales, driven largely by solar exposure. These diurnal changes likely influence the probability of firebrand production during fire events via controls on moisture (ignition) and peeling (lofting).
Towards An Integral Therapeutic Protocol for Breast Cancer based upon the New H+-Centered Anticancer Paradigm of the Late Post-Warburg Era
Authors: Harguindey Salvador , Alfarouk Khalid , Polo Orozco Julián , Fais Stefano , Devesa Jesús
Published: September 2020

A brand-new approach to the understanding of breast cancer (BC) is urgently needed. In this contribution, the etiology, pathogenesis, and treatment of this disease is approached from the new pH-centric anticancer paradigm. Only this Unitarian perspective based upon that the hydrogen ion (H+) dynamics of cancer, allows understanding and integrating the many dualisms, confusions, and paradoxes of the disease. The new H+-related wide range model can embrace under a unique frame of mind the many aspects of the disease and at the same time therapeutically interfere with most, if not with all, the hallmarks of cancer known to date. The pH-related armamentarium available for the treatment of BC here reviewed may be beneficial for all types and stages of the disease. In this vein, we have attempted a mega synthesis of traditional and new knowledge in the different areas of breast cancer research and treatment based upon the wide range approach afforded by the hydrogen ion dynamics of cancer. The concerted utilization of a pH-related drugs nowadays available for the treatment of breast cancer is advanced.
Energy Metabolism Decline in the Aging Brain; Pathogenesis of Neurodegenerative Disorders
Authors: Błaszczyk Janusz
Published: September 2020

A growing body of evidence indicates that aging of the brain is strictly related to the decline of energy metabolism. In particular, in older adults, the neuronal metabolism of glucose declines steadily resulting in a growing deficit of ATP production. The decline is evoked by deficient NAD recovery in the salvage pathway and subsequent impairment of the Krebs cycle. NAD deficit impairs also the activity of NAD-dependent enzymes. All these open vicious circles of neurodegeneration and neuronal death. Some brain structures are particularly prone to aging and neurodegeneration. These are pathological foci of neurodegenerative diseases such as Alzheimer’s and Parkinson’s disease. This review article summarizes the impacts and mutual relationships between metabolic processes both on neuronal and brain levels. It also provides directions on how to reduce the risk of neurodegeneration and protect the elderly against neurodegenerative diseases.
TÜRKİYE’DE SAĞLIK ALANINDA MALİYET ÜZERİNE YAPILAN ARAŞTIRMALARIN BİBLİYOMETRİK ANALİZİ
Authors: AKBULUT Fevzi
Published: September 2020

Bu çalışmanın amacı Türkiye’de Dergipark’ta yayınlanan sağlık sektöründe maliyet alanında yapılan makalelerin incelenmesidir. 2011-2018 yılları arasında yayınlanmış makaleler bibliyometrik analiz yapılarak incelenmiştir. Analiz çerçevesinde 5625 yayın arasından 113 tanesinin sağlık sektöründe maliyet alanında yapıldığı tespit edilmiştir. Tespit edilen 113 makale; yazar sayıları, sayfa sayıları, yıllara göre dağılımları, dergilere göre dağılımları, illere göre dağılımları, anahtar kelimeleri, atıf sayıları, yazarların kurumlara göre dağılımı, unvan sayıları, yayınlandığı bölgelere göre ve maliyet yönetim yaklaşımlarına göre dağılımları bibliyometrik yöntemle analiz edilmiştir. Sonuç olarak, çalışmaların büyük çoğunluğunun hastanelerde yapıldığı görülmektedir. Veri seti olarak, hasta ve personel bilgilerinden, hastanenin direkt ve endirekt giderlerinden yararlanıldığı tespit edilmiştir. Genellikle nicel yöntemler kullanılarak yapılan çalışmaların, %59,8’inin İç Anadolu ve Marmara Bölgesi’nde yapıldığı, %30,9’unun ise Ankara ve İstanbul illerinde yapıldığı sonucuna ulaşılmıştır. Yapılan çalışmanın hem hastane yöneticilerine hem de bu alanda yapılacak çalışmalara önemli katkılar sağlayacağı düşünülmektedir.
Planejamento Municipal em Debate: Trajetória e Prioridades no Município de Florianópolis
Authors: Menezes Elaine Cristina de Oliveira , Schommer Paula Chies , Rocha Arlindo Carvalho , Pozzobon Fernando
Published: September 2020

O presente artigo analisa as prioridades do planejamento no âmbito do município de Florianópolis, nas últimas cinco décadas, com o objetivo de compreender como este processo vem se desenvolvendo. Para tanto, tendo como ponto de partida a matriz teórica do planejamento para o desenvolvimento e a abordagem do planejamento gerencial, traça-se a trajetória do planejamento governamental brasileiro para, a partir daí, examinar as prioridades na alocação de recursos determinadas nos sucessivos orçamentos municipais. A pesquisa é de cunho predominantemente qualitativo, com avaliação documental e se utiliza do método histórico-interpretativo. Os resultados demonstram que o planejamento do município de Florianópolis seguiu a tendência do planejamento nacional e estadual. Num primeiro período voltado para o planejamento para o desenvolvimento, com ênfase em áreas de infraestrutura e, num segundo momento, com base numa agenda gerencial e de apelo social, com ênfase nas áreas de saúde e educação.
Quality of life of blind people’s carers
Authors: Lewandowski Łukasz , Smotryś Iwona , Puls Angelika , Radziejewska Anita , Płocharczyk Magdalena , Reczek-Chachulska Aldona , Wieder-Huszla Sylwia
Published: September 2020

Introduction: Quality of life is a multidimensional concept and a subjective value that depends on many factors. Disability caused by sight loss induces changes for both patients and their carers. The function of a blind person’s carer is usually performed by family members, whose limited knowledge limits their ability to help effectively and satisfactorily. This, in turn, may lead to their reduced sense of the quality of life.

The aim of this study was to assess the quality of life of blind people’s carers.

Materials and methods: The study was conducted September– October 2016 and involved 130 blind peoples’ carers using a diagnostic poll. Short Form Survey SF-36 and a specially designed questionnaire were used. The majority of participants were women (69.23%), married couples (63.1%), with high school education (40.77%).

Results: Wellbeing self-assessment indicated that 36.15% of carers considered their mental condition to have worsened, while 43.08% remained at the same level when compared to 1 year earlier. Analysis of quality of life showed that carers very highly rated their physical functioning 59.46 ±26.35; social functioning 57.4 ±26.12; vitality 55.48 ±23.27; and emotional functioning 54.81 ±29.24.

Conclusions: Quality of life tends to gradually deteriorate as the carers grow older. The carer’s educational background and the professional activity of the disabled person influence the assessment of the carer’s quality of life.
The level of acceptance of the illness among patients with psoriasis
Authors: Budzińska Kinga , Kożybska Marta , Zabielska Paulina , Knyszyńska Anna , Kamińska Magdalena , Pierzak-Sominka Joanna , Karakiewicz Beata
Published: September 2020

Introduction: Psoriasis is a chronic inflammatory and non--infectious skin disease. It is one of the most common dermatoses. Increased reproduction of the epidermis and, as a consequence, visible skin lesions negatively affect the patient’s psyche, disrupt self-esteem, reducing the chance of accepting the disease and a normal life.

The aim of this study was the assessment of the level of acceptance of the illness and identification of factors affecting its acceptance among patients with psoriasis.

Materials and methods: The study involved 132 individuals, comprising 113 women and 19 men. This survey-based study was conducted via the Internet using the author’s questionnaire and the Acceptance of Illness Scale (AIS).

Results: Acceptance of the illness level was rated great and moderate by respectively 43.9% and 39.4% of respondents. Over 66.7% of the patients described their self-esteem as high obtained

a great level of acceptance of the illness according to the AIS. In the examined group, 58% of the patients not accepted psoriatic lesions on their body. Over 60% of the respondents experienced negative reactions from society regarding the disease, and almost 50% of them experienced other people’s reactions resulting from concerns about contracting the disease; these patients obtained lower AIS scores.

Conclusions: The obtained results indicate a great illness acceptance among the examined group of the patients with psoriasis. The level of acceptance was influenced by the patient’s self--esteem in relation to the disease, acceptance of their own body image, altered by the disease, experiencing the negative reactions from the society regarding the disease, and the reactions of the other people resulting from concerns about contracting the disease.
Delivering bad news in the perspective of patient rights
Authors: Sobczak Krzysztof , Leoniuk Katarzyna , Janaszczyk Agata
Published: September 2020

Introduction: The necessity to deliver bad news to patients is one of the classic challenges of medical communication. The applicable patient rights oblige doctors to communicate full information concerning adverse condition tactfully and cautiously. The purpose of the study was to determine the level of knowledge of the rights and responsibilities of the patient in people who had received bad news, to identify the fields in which knowledge is lacking and to check if the level of knowledge affected the patient’s behaviour.

Materials and methods: The study was conducted with 314 people who had been given bad news. An original Computer-Assisted Web Interview (CAWI) online survey questionnaire was used. Reaching the respondents was possible thanks to our cooperation with national patient organisations and electronic media.

Results: One in 5 respondents (21%) was characterised by little knowledge concerning patient rights and responsibilities; 67% had a moderate level of knowledge or were almost fully aware of their rights. A vast majority of the respondents knew that they were entitled to full information about their condition, prognosis and treatment, as well as an inspection of their medical documentation.

Conclusions: The knowledge of patient rights seems to be at an unsatisfactory level. Respondents with a higher education and those suffering from cancer had more knowledge. Patients with little or a moderate level of knowledge of patient rights and responsibilities were more likely to change their attending physicians or discontinue their treatments.
In-Situ Generation and Propagation of Well-Defined Nanocellulose Strengthened Gaseous and Supercritical Carbon Dioxide Foams in Tight Formation Fractures for Conformance Control
Authors: Wei Bing , Chen Shengen , Tian Qingtao , Lu Jun , Xu Xingguang
Published: September 2020

Foam stability primarily determines the efficiency of foam-induced conformance control, especially when fractures exist in formations. In this work, a well-defined nanocellulose fibril (NCF)-strengthened carbon dioxide foam (NCF-st-CO2 foam) was proposed, aiming to improve the conformance of tight formations with fractures. The bulk characteristics of NCF-st-CO2 foam including foamability, foam stability, and texture were thoroughly investigated in a high-temperature and high-pressure (HT-HP) cell. Afterward, foam flow in fracture models was simulated, intending to correlate the generated differential pressure with the parameters of foam quality, fracture aperture, and fluid velocities, which helped to understand the foam generation, propagation, and mobility in fractures. The capacity of this foam in controlling conformance and improving oil recovery in a fractured core was finally evaluated. Conventional CO2 foam (without NCF) was used as the reference throughout this work. The results indicated that the addition of NCF into CO2 foam considerably retarded the liquid drainage and bubble coalescence, which consequently stabilized the CO2 foam, especially in the presence of crude oil. NCF-st-CO2 foam presented dense bubbles and a thick framework as observed visually from the cell. The flow behaviors of CO2 foam in fractures were largely determined by the bulk foam stability. NCF-st-CO2 foam could be generated in situ (aperture from 0.5 to 5.0 mm) and then properly propagated throughout the fractures at a low mobility without any plugging issues. In coreflooding tests conducted on the model with fracture aperture of 0.5 mm, the NCF-st-CO2 foam injection exhibited a delayed breakthrough, which finally led to an incremental oil recovery of 8.6% original oil in place (OOIP) after conventional CO2 foam treatment. These results demonstrated the promising potential of NCF-st-CO2 foam in conformance control in tight formations.
Multivariate Optimization of the Development Systems for Low–Permeability Reservoirs of Oil Fields of the Achimov Formation
Authors: Fedorov Aleksei Eduardovich , Dilmuhametov Ilshat Rashitovich , Povalyaev Andrey Aleksandrovich , Antonov Maksim Sergeevich , Sergeychev Andrey Valerievich
Published: September 2020

The aim of this work is to develop an approach to multivariate optimization of development systems for tight oil reservoirs of the Achimov formation, where large volume of drilling of RN-Yuganskneftegaz LLC are currently concentrated on. The approach described in the paper is an integral part of the corporate module "Decision Support System for drilling out new sections of tight oil reservoirs", which allows making quick design decisions for new drilling sites of target objects.

The main factors that reduce the development efficiency of such objects, in particular with the use of water flooding methods, are the low piezoconductivity and high heterogeneity of a reservoir that leads to relatively high rates of decline in fluid production and, in particular, to long response productivity time for production wells to injection.

In this paper, we consider a multi-criteria assessment of the effectiveness of various well placement systems in various conditions that characterize the geological features of tight oil reservoirs and low-connected reservoirs. A specific example is considered - tight oil heterogeneous reservoir of the northern part of Priobskoye field, for which oil production is calculated by numerical hydrodynamic modeling methods.

As a result of development and testing of the approach:

Main geological and technological parameters are estimated that affect development indicators and empirical dependencies derivation (of the development indicators) on the geological features of the selected clusters of Priobskoye field target objects; A method being proposed for description of a various geological features of the reservoirs of Achimov formation target objects by using synthetic stochastic 3D geological models; A physically-meaningful approach is proposed for adaption of well dynamics that reveal tight oil reservoirs of target objects using synthetic 3D geological and hydrodynamic models. Based on the actual data of development (well operation), formation parameters are determined for each cluster (section) of the target objects of Priobskoye field, which differ in geological features and development indicators; Prediction multivariate numerical calculations were carried out for various well placement systems under various geological conditions (≈ 3 million calculations). A database of calculated development indicators has been formed for each variation of the well placement system; Different options are presented for visualization of calculation results in the form of dimensional templates of optimal development systems for tight oil reservoirs; Various options for sensitivity analysis visualization for the effectiveness assessment are presented of various well placement systems to changes in geological, technological and scenario conditions.
Evaluation of a Field-Wide Post-Steam In-Situ Combustion Performance in a Heavy Oil Reservoir in China
Authors: Zhao Fang , Xi Changfeng , Zhang Xialin , Shi XiaoRong , Yang Fengxiang , Mu Hetaer , Guan Wenlong , Jiang Youwei , Wang Hongzhuang , Babadagli Tayfun , Li Huazhou
Published: September 2020

We evaluated the performance of a field-wide post-steam in-situ combustion (ISC) project conducted in a complex heavy oil reservoir in China using laboratory one-dimensional combustion experiments, reservoir simulation outputs, and data collected from the field application. The commercial ISC project showed vastly different production performances in different regions of the field and two types of representative well groups were identified. Type I group has a low oil viscosity (<8000 mPa.s) and a high steam-flooded recovery factor (>30%); after ISC treatment, these producers show a high initial water cut, while some experience channeling issues and hence produce a large quantity of flue gas. Type II group has a high oil viscosity (>20000 mPa.s) and a low cyclic steam stimulation (CSS) recovery factor (15-20%); these producers have a high air injection pressure exceeding the fracture pressure. Corresponding remedial methods were designed and applied to these two well groups. Presently, the evaluation methods described in this paper are being applied in the field, and initial results have been acquired.
Potential and Possible Technological Solutions for Field Development of Unconventional Reservoirs: Bazhenov Formation
Authors: Bukharov Dinar Farvarovich , Alekseev Yuri Vladimirovich , Prodan Artem Sergeevich , Nenko Artem Valerevich
Published: September 2020

The "shale revolution" experience on the example of the Bazhenov formation (BF) development required a serious development program review and implementation.

The modern approach to the Bazhenov formation development in the Russian Federation is approaching the final stage of the existing formation stimulation technologies improvement. The technical limit in completion is about to be reached. It becomes obvious that existing stimulation technologies do not allow creating more efficient "reservoir factories" in the Bazhenov formation. The paper's objective is an attempt to identify hypotheses and prerequisites, as well as possible prospects for the stimulation technologies development, to justify the use of new alternative systems for hydraulic fracturing (HF) with an assessment of their potential at the BF reservoirs.
Results of the First Polymer Flooding Pilot at East-Messoyakhskoe Oil Field
Authors: Ilyasov Ilnur , Gudz Anton , Podkorytov Alexander , Komarov Vladimir , Glushchenko Nikolai
Published: September 2020

East-Messoyakhskoye is a giant oil green field, unique in terms of oil reserves, located in arctic conditions. The main distinctive field characteristic is viscous oil in the cold, unconsolidated reservoir.

Understanding all the challenges of developing such reservoirs, a proactive study of polymer flooding began at an early field development stage. A lot of study and research has been done, including the full range of necessary elements.

This paper summurises the first pilot project results, gained experience and achievements that allowed us to successfully implement the pilot project, confirm the prospects of polymer flooding technology and lay the foundation for further work.
Numerical Simulation of Polymer Flooding
Authors: Mirsayanova Elina , Ilyasov Ilnur , Cheremisin Alexander , Evseeva Margarita , Cheremisin Alexey
Published: September 2020

Many factors affect the efficiency of polymer flooding, but the key is polymer adsorption on the rock. The analysis of the main methods of experimental elaboration of uncertainties associated with the estimation of adsorption on micromodels is carried out in this article. As part of this work, the following studies were carried out:

review of existing research methods and measurement of adsorption parameter; analysis of relevant uncertainties (adsorption, core, model) and methods for their reduction; carrying out subtle approaches in the study of adsorption on core samples using a filtration unit and measuring the polymer concentration by spectrophotometry; reproduction of the performed experiments on the core on the scale of the micromodel.

The main problems, which are reflected in detail in the course of the experiments, are the complexity of measuring the concentration spectra in the presence of the hydrocarbon phase. This problem was solved by extracting core samples followed by pumping 4 pore volumes of polymer solution of hydrolyzed polyacrylamide Flopaam 3630S.

The main results of the experiments made it possible to clarify the value of dynamic adsorption in the range of permeabilities 450 - 1100 mD for the PK1-3 layers of the East-Messoyakhskoye field. Thus, it was found that the average adsorption value is 338 μg / kg of rock. The results of filtration experiments were modeled in a commercial hydrodynamic simulator, which will allow in the future to assess the effectiveness of polymer flooding for a geological object of field development, to assess polymer losses during its filtration, and to clarify the economic risks associated with the project.
EOR Technology: Surfactant-Polymer Injection to Increase Oil Recovery from Carbonate Reservoir of Kharyaga Oilfield
Authors: Trushin Yuri , Aleshchenko Anton , Arsamakov Mark , Klimenko Alexandra , Molinier Valérie , Jouenne Stephane , Kornilov Alexey , Sansiev George
Published: September 2020

The paper reports on the procedures of selection and evaluation of surfactant-polymer composition to improve the development efficiency of Kharyaga field D3-III carbonate formation. The main goal was to establish an efficient chemical composition that could significantly improve oil recovery factor and are compatible with high salinity formation (up to 170 g/l) and injected water (60-80 g/l) at formation temperature 62°C. Laboratory results include the composition screening and core flood experiments on analogous carbonate cores; the best prospective scheme of injection is validated. A physico-chemical model of oil displacement at negative salinity gradient is validated with technical calculations. Additional laboratory program is currently planned for validation of uncertainty parameters. It includes displacement of oil by surfactant and polymer solutions on Kharyaga field cores and evaluation of dynamic adsorption of chemicals.
Practical Experience in Applying the Technology of Creating a Network of Deep-Penetrating Filtration Channels with the Intensification of the Inflow in the Producing Wells of the Republic Unitary Enterprise Production Association Belorusneft
Authors: Plekhanov Stsiapan Nikolaevich , Moisseyeu Dzianis Vladimirovich
Published: September 2020

The staff of Belorusneft constantly invents, tests and adopts new technologies to develop hard-to-recover oil reserves in the fields of the Pripyat Trough. Conventional reserves are under fast-paced development in this region, while hard-to-recover reserves are not actively developed, although amounting up to 70% of total recoverable petroleum reserves. When targeted penetration of low-permeable intervals and creation of a system of branched deep drainage channels are required, we developed equipment and technology that allow creating a network of deep-penetrating flow channels. The channels run radially in relation to the wellbore with penetration depth of up to 100 m, which can significantly increase the formation fluid flow area toward the wellbore.
A Case Study of Salt-Tolerant Functional Polymer For EOR in Carbonate Reservoirs with Ultra-High Salinity
Authors: Mustafin Aidar Zamilevich , Li Kexing , Varfolomeev Mikhail Alekseevich , Yuan Chengdong , Kadyrov Rail Ilgizarovich , Glukhov Mikhail Sergeevich , Khayrtdinov Ruslan Kamilevich , Pu Wanfen , Sattarov Aidar Ildarovich , Statsenko Evgeny Olegovich
Published: September 2020

In this work, we present a new-type salt-tolerant functional polymer (CBHB) for ultra-high salinity conditions, and investigated its feasibility for polymer flooding in a fractured carbonate reservoir with a salinity of more than 220000 mg/L (Ca2+ + Mg2+ > 10000 mg/L) in Akanskoe oilfield (Tatarstan, Russia). First, the properties of the salt-tolerant functional polymer (CBHB), including solubility, rheological parameters, and long-term stability etc., were evaluated at different salinity conditions and compared with current commercial polymers (total 15 samples). Then, the static and dynamic adsorption were determined using UV-spectroscopy. Finally, regular filtration experiments on a laboratory scale and 4D X-ray tomography core flooding experiments were carried out at reservoir conditions to analyze the microscopic/macroscopic displacement mechanism and efficiency of polymer in real time.

The results showed that only three polymers can be dissolved at 227500 mg/L salinity and 23 °C (reservoir temperature) and give homogenous solution with the viscosity of higher than 100 mPa·s at the polymer concentration of 2000 mg/L. CBHB showed the highest viscosity of 830 mPa·s after aging for 180 days, which means that it has a superior salt tolerance ability. 4D X-ray tomography indicated that polymer displacement front is aligned and even oil in some small pores or caves can be also displaced with almost no oil film left due to a good viscoelasticity of polymer. A high displacement efficiency of 72.94% was achieved. This means that this CBHB polymer not only has the traditional mobility control capacity to increase sweep efficiency, but also have ability to increase displacement efficiency, which makes CBHB polymer have a great potential for EOR in ultra-high salinity reservoirs.

Salt-tolerant functional CBHB polymer for ultra-high salinity of more than 220000 mg/L (Ca2+ + Mg2+ > 10000 mg/L) was developed. It exhibited both high sweep and displacement efficiency due to its functional groups. This will expand the application of polymer flooding for ultra-high salinity reservoirs. Simultaneously, 4D X-ray tomography was innovatively used to precisely investigate the microscopic/macroscopic displacement mechanism and efficiency of polymer flooding.
Smart Bridging Agent - Prevents Formation Damage and Removed with Formation Fluid
Authors: Popov Sergey Viktorovich , Nikitin Pavel Mikhalovich , Udaltsov Denis Aleksandrovich , Ryabtsev Petr Leonidovich
Published: September 2020

Sized calcium carbonate is the most common material used in reservoir drill-in fluids for filter cake deposition. Calcium carbonate has numerous advantages relating to to drilling fluids but also some limitations. Research and field works were performed from mid-2018 to late 2019 to develop and implement a new material that can be used as an efficient alternative to calcium carbonate.

This article describes actual results of the research and field works performed to develop and implement an innovative bridging agent for water-base drilling fluids. The chemical is intended to build a filter cake and has a number of unique properties. The new material enables the solution of certain engineering tasks arising when drilling horizontal wells in a producing formation, in particular, preventing formation damage and increasing development efficiency. The article covers main methods used to elaborate the material and results of pilot works.
Experience of Existing Casing Drilling Technologies in Various Conditions and Search of the New Solutions for Actual Challenges
Authors: Zakirov Artem Yaudatovich , Kartinen Daniil Yurievich , Madyarov Alik Irekovich
Published: September 2020

The components of casing drilling technology are evolving and the application area is expanding. Drilling engineers today have more flexibility than ever before to redesign wells and can combine different technologies, materials and equipment to achieve new records in well construction efficiency. In recent years, PJSC Gazpromneft has been constantly using casing drilling technologies. The increasing complexity of geological conditions and the need to reduce well construction costs lead to more efficient solutions.

The article presents the actual experience of using the following variations of the casing drilling technology:

Non-directional drilling on 426mm casing together with 630mm thermal case at Yamburgskoye field Non-directional drilling on 324mm casing at the Vostochny Section of the Orenburg oil and gas condensate field (VUONGKM) Run in hole with rotation on 245mm casing at VUONGKM. Directional drilling with 245mm casing with a retrievable BHA at VUONGKF.

The use of casing drilling technology has not in all the cases under consideration increased the efficiency of well construction, but at the same time the results obtained allow us to predict an additional increase in the efficiency of the application of these technological solutions.

At the end of the article, a tree of casing drilling technologies was built and segments with development prospects were highlighted.
Innovative Approach for Multilateral Well Completion with TAML 3 Junction Installation in Open Hole
Authors: Erokhin Dmitry Andreyevich , Kashlev Alexander Sergeyevich , Fedotov Andrey Gennadyevich , Pyatkov Evgeny Sergeyevich , Philippov Alexander Viktorovich , Samarin Grigoriy Borisovich , Ivashkin Evgeny Vladimirovich , Solovyev Vladimir Vladimirovich
Published: September 2020

Multilateral well completion technologies are becoming more common throughout the lifecycle of oil and gas fields due to increasing complexity of the reservoirs. Additional lateral drilling tends to increase the contact area with the formation and, as a result, the production rate of a well and allows avoiding the need of design, construction, and maintenance of the surface infrastructure and upper sections of a potential new well. (Muslimov R.H., 2017)

Various factors are considered while designing the well construction: starting from reservoir properties, thermobaric conditions, fluid composition, and up to the surface infrastructure. So, a Multilateral well might be a good solution under certain circumstances. (Shenberger V.M., 2007)

In Russia, the most popular Multilateral completion technology nowadays is level 1 according to TAML1 international classification (with both lateral cased). The noteworthy strengths of the system include its reliability, simple deployment, and proven cost-effectiveness. However, its widespread use is hindered by such constraints as a fundamental limitation associated with the inability to perform following downhole operations (DHL2, HCT3, processing of BHZ4, etc.) in one of the boreholes, which directly affects the effective lifetime of such a well.

Technologies TAML 2 and 3 are the next levels in the international classification describing the construction of a Multilateral well with an exit from previous casing (mainbore). (Bellarby J., 2009) However, the TAML 2 system was not considered for this case due to the lack of mechanical integrity of the junction. The basic TAML 3 system requires both a longer well completion time and additional operations entailing associated risks.

In view of the above, a further development of TAML 1 technology was considered as a solution: Multilateral well completion with TAML 3 junction installation in the open hole preserving its mechanical integrity, with the possibility of selective access to both laterals during following downhole operations without involving additional service equipment.1 TAML - Technology Advancement for Multi-Laterals.

This paper describes the field experience of TAML 3 system deployment in the open hole for the land project, which confirmed the effectiveness of an integrated approach and targeted solutions for further optimization of hydrocarbons production by the example of the Multilateral well construction.
Application of Cemented Multi-Entry Frac Sleeves in Multistage Stimulation: A Case Study
Authors: Stolyarov Sergey , Bagci Suat , Gomez Ricardo , Wright Beau , Yang Junjie
Published: September 2020

Plug and Perf (PnP) completions have been the most widely used multistage hydraulic fracturing methods used in unconventional wells. In a PnP completion, isolation between stages is achieved by setting frac plugs inside the horizontal liner. The number of perforation clusters and perforation holes are designed using limited entry perforating techniques.

While PnP is a proven method, there are also some downsides, particularly when considering the inability to pump plugs due to changes in casing integrity and casing deformation occurring in 20-30% of horizontal wells. Casing damage has been increasingly recognized as a challenge to well integrity in active or child wells during multistage hydraulic fracturing. Casing deformation and reduction in casing inside diameter (ID) prevent the use of PnP operations due to frac plugs being unable to pass through deformed casing.

Cemented multi-entry frac sleeves (MEFS) allow users to imitate the limited entry effect of PnP completions while eliminating the need to deploy large OD frac plugs for each stage. The multiple entry points are activated using various-sized frac balls dropped from the surface as the stimulation treatment is pumped, eliminating the need to rig up and rig down between stages. After fracturing is complete, the frac balls either dissolve or are flowed to surface allowing production to begin immediately—eliminating through-tubing intervention. The multi-entry sleeves use graduated balls and ball seats to open as many as five sleeves per stage with a single frac ball for increased efficiency. Number of clusters and entry points are calculated based on limited entry techniques similar to PnP.

Within this study, two limited entry techniques, PnP and multi-entry sleeve systems, are evaluated using commercial fracture modeling software, and well production modeling to compare the steady-state production between PnP and multi-entry sleeves. Hydraulic fracture modeling is also used to evaluate limited entry perforation design, perf erosion, stress shadowing, and fracture propagation.
Successful Application of High-Speed Negative-Pulse Telemetry with Compressed Data Transmission Aiming to Increase ROP during Horizontal Wells Drilling in Yuzhno Tambeyskoye Gas Condensate Field
Authors: Garipov Andrey , Tur Dmitry , Galimkhanov Aydar , Khalilov Almaz , Yavorsky Alexander , Maltsev Vladimir , Pogurets Valery , Rybalkin Aleksey
Published: September 2020

This paper describes the results of efficient cooperation between the Operator, the General Drilling Contractor and the Service Company, who participated in the construction of horizontal wells in Yuzhno-Tambeyskoye gas condensate field.

This document describes an integrated engineering approach to selection of new technical and technological solutions, which safely achieved all the geological tasks while constructing the wells.

The key innovations of real-time data transmission from downhole tools, allowed the quality of the information received to be improved which increased the average rate of penetration (ROP) and reduced the well drilling time. Furthermore, during the project execution a multidisciplinary group of experts developed and successfully implemented a set of measures aimed at reducing flat time.

Comprehensive planning, an efficient organizational structure, effective communication between all the participants and the introduction of new technologies resulted in the safe and successful construction of 6 horizontal wells with 1500 m long horizontal sections delivered 10% ahead of schedule.

Along with the technological progress, it is important to note that during well construction a high level of HSE was achieved with no accidents occurring throughout the entire project.
Plunger Lift System Case Studies in Kazakhstan
Authors: Nurkas Zhassulan , Khabibuyev Khajirakhim
Published: September 2020

Plunger Lift is an efficient method of producing hydrocarbons for a "specific" well conditions. The most important part of the application process is to select the wells with appropriate conditions. Typical Plunger Lift applications are (E. Beauregard, L. Ferguson, 1982):

removal of liquids from gas wells; high gas liquid ratio wells; paraffin and hydrate control; increasing efficiency of gas lift applications (especially for an intermittent gas lift); Further technology studies as well as field pilot projects extended application range of the systems and to the date plungers also being used to (E. Beauregard, S. Morrow, 1989): produce liquids in extremely low pressure reservoirs; produce liquids in retrograde condensate wells; remove water from coal seam methane gas wells; produce liquids in deviated and horizontal wells; prevent downhole freezing problems in high pressure gas wells.

Besides applications listed above, there is also a specific window for a Plunger Lift – well conditions with high gas liquid ratio, where traditional SRP and ESP systems are severely challenged.

Despite the wide and effective application range of the technology and quick payout period, the major obstacle to more widespread utilization of plungers has been a lack of education. This has been a problem not only with operational personnel but engineering and management as well. Key figures on Plunger Lift technology, founders of PCS Ferguson company, Beauregard and Ferguson were mentioning this early in 80-s as the main barrier. Since this period number of Plunger Lift installation is continuously growing in North America and reached up to 4% of total well count, which is today about 30 000 wells.

Nevertheless, in Eastern Hemisphere implementations of plungers are only at the beginning stage.

This paper discusses the latest Plunger Lift applications in Kazakhstan, obtained results, there are also some operational guidelines on more effective implementation ways.
Effectiveness of Implementing ESP Life Cycle System in Salym Petroleum Development
Authors: Musorina Anastasia Dmitrievna , Safonov Viktor Nikolaevich , Ishimbaev Grigory Sergeevich
Published: September 2020

Fluctuations of macro-economic indicators, global financial crises and supply excess over demand at the oil market have historically been the reasons for the oil industry profitability decline. On the one hand, it certainly influenced the revision and reduction of investment projects, and on the other hand, it more than ever reflected the importance of improving oil production efficiency and reducing its cost. Salym Petroleum Development (SPD), as a producing company, has always paid considerable attention to improving the efficiency of oil and gas production processes, the reliability of running equipment and the quality of process operations. In 2016, SPD changed its systematic approach to DPE (down-hole pumping equipment) operation and oil production optimization by implementing the "ESP Life Cycle" system, which involves a detailed review and improvement of each stage of the ESP life cycle (Figure 1).
Determination and Forecast of Formation Pressure, Productivity and Reservoir Properties Based on Well Production Analysis Using Kappa Topaze Software Without Shutdown of Wells Equipped with Downhole Pressure Gauges and Telemetry Systems for LUKOIL-PERM LLC Fields
Authors: Kuznetsova Elena Aleksandrovna , Shilov Aleksandr Vladimirovich , Nikulin Sergei Evgenyevich , Chernykh Irina Aleksandrovna
Published: September 2020

Flow testing (FT) is an integral part of any field development. Testing results are used to plan well interventions, analyze the current field development state and make up project documents. However, this testing implies significant financial losses caused by incomplete oil recovery due to time-taking well shut-ins for up to several months, which is especially relevant to horizontal wellbores, fractured wells, low-permeability reservoirs.

The production analysis method described in this article allows assessing the same set of reservoir and well parameters as that used for the traditional flow testing, but without oil production losses. The method was tested on 95 wells of the LUKOIL-PERM LLC fields. In order to assess the credibility of the obtained reservoir parameters, the authors made a comparison with the pressure build-up (PBU) interpretation results. The good convergence for the key reservoir properties revealed for most wells testifies that the method is promising as a supplement to transient flow testing.

The authors developed criteria and determined an area of application for this type of testing for Owner's fields after studying specialized plots, identifying the dependence of results on the quality of input data, as well as assessing the forecast capabilities of the production analysis method.
Application of Pressure Interference Test Without Stopping the Well Stock to Regulate the Process of Field Development of the NOVATEK Group of Companies
Authors: Dvinskikh Kristina , Zavalin Fedor , Naimushin Anton , Abdrakhimov Aleksandr
Published: September 2020

The main objectives of field development are to maintain high profitability, as well as to achieve the highest coefficient of oil recovery (COR). One of the ways to ensure a high COR for oil fields is creation of a reservoir pressure decrease system (RPD). So, for example, when create a system of RPD, the COR can reach 0.5 d. q., and without RPD - only 0.1-0.2 d. q In the case of designing the development of oil fields with a complex geological structure (the presence of a gas cap, block structure of the Deposit, a large number of faults), the complexity of the task of choosing the optimal development system increases significantly.

In Russia and in the world, there are a considerable number of oil fields that have been developed for a long time on the depletion mode, which has led to the formation of a considerable volume of the free gas phase. Such deposits often pass into the category of problematic and are characterized by low current values of the coefficient of oil recovery (COR), as well as the lack of reliable technological solutions for their effective development. Examples include the Talinsky area of the Krasnoleninsky field, the oil pool in the Jurassic sediments of the Novogodnee Deposit, and others. When the pressure increases further, for example, by pumping water, modeling the development of such deposits requires the use of non-equilibrium hydrodynamic models.

Application of the results of the pressure interference test (PIT) allows us to obtain valuable information about the connectivity of inter-well intervals, a quantitative assessment of the conductivity of reservoir faults, and, consequently, reduce risks when planning field development, increase the efficiency of ongoing geological and technical measures and their profitability. Conducting of PIT on a working stock, in comparison with classical methods, allows you to minimize the loss of production during research. Proper planning of field development with the involvement of PIT results, in particular-the introduction of the RPD system, allows to increase the COR and profitability of the development system as a whole.

The paper shows the results of the pressure interference test studies for a tectonically complicated structure of an oil and gas condensate field. Based on the results of the research, the efficiency of the existing RPD system was evaluated and decisions were made to transfer production wells to injection, taking into account the assessment of the risks of water breaks through conducting faults. In addition, the results of the pressure interference test were combined with the results of tracer studies. The convergence of research results by both methods is shown.