scholarly journals Improving the waterproofing efficiency by using a plugging compound

2021 ◽  
pp. 192-200
Author(s):  
I. G. Fattakhov ◽  
◽  
L. S. Kuleshova ◽  
Sh. Kh. Sultanov ◽  
V. V. Mukhametshin ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Water Inflow ◽  
Well Water ◽  
Mass Percent ◽  
Solid Ratio ◽  
Advantages And Disadvantages ◽  
Formation Zone ◽  
Water Cut ◽  
Polyaluminium Chloride ◽  
Over Time

Increasing the efficiency of water shut-off works is one of the important tasks for the sustainable well operation. The article discusses the use of various plugging compositions for water inflow into a well isolating, their advantages and disadvantages, conditions of use, and presents the results of a study of the proposed composition. The composition of an aqueous solution of polyaluminium chloride and a suspension of gypsum anhydrite is considered. The composition contains 45-55 mass percent of 15-25 percent aqueous solution of polyaluminium chloride and 45-55 mass percent suspension of gypsum anhydrite at a water-solid ratio of 0.9. The technical result is an increase in the efficiency of water inflow into the well isolating by obtaining a homogeneous, dense plugging mass formed by mixing the components of the composition and gaining maximum strength over time. Keywords: well; water cut; isolation; water inflow; plugging mass; bottomhole formation zone; oil production; polyaluminium chloride; anhydrite.

Studying dispersed and rheological properties of hydrocarbon-containing acid emulsions and their efficiency in removing asphalt-resin-paraffin deposits

2020 ◽  
pp. 128-139
Author(s):  
M. Yu. Shumakher ◽  
V. V. Konovalov ◽  
A. P. Melnikov
Keyword(s):  
Aqueous Solution ◽  
Hydrochloric Acid ◽  
Rheological Properties ◽  
Reaction Rate ◽  
Experimental Studies ◽  
Efficient Removal ◽  
Reservoir Properties ◽  
Hydrocarbon Solvents ◽  
Formation Zone ◽  
Effect Of The Composition

Currently, the treatment of the bottomhole formation zone with acidic compositions is one of the most common methods to intensify the oil inflow. The use of various modified acid compositions increases the efficiency of acid treatments on the bottomhole formation zone. Acid compositions, including those containing hydrocarbon solvents, which contribute to more efficient removal of organic colmatants, affect the reaction rate of the reagent with the rock and processing equipment, change the reservoir properties, etc.The article presents the results of experimental studies, which are aimed at establishing the effect of the composition of hydrocarbon-containing acidic emulsions consisting of an aqueous solution of hydrochloric acid, toluene and Neonol AF 9-10 on their dispersed and rheological properties, as well as their efficiency in removing paraffin deposits.

Comparison of a Non Electrostatic Surface Complexation Model and Surface Phase Theories for Prediction of Future Sorption Properties.

2004 ◽  
Vol 824 ◽  
Author(s):  
Allan T. Emrén ◽  
Anna-Maria Jacobsson
Keyword(s):  
Aqueous Solution ◽  
Chemical Potential ◽  
Surface Complexation ◽  
Sorption Properties ◽  
Phase Method ◽  
Detailed Knowledge ◽  
Surface Phase ◽  
Surface Complexation Model ◽  
Advantages And Disadvantages ◽  
The One

AbstractIn performance assessments, sorption of radionuclides dissolved in groundwater is mostly handled by the use of fixed Kd values. It has been well known that this approach is unsatisfying. Only during the last few years, however, tools have become available that make it possible to predict the actual Kd value in an aqueous solution that differs from the one in which the sorption properties were measured.One such approach is surface complexation (SC) that gives a detailed knowledge of the sorption properties. In SC, one tries to find what kinds of sorbed species are available on the surface and the thermodynamics for their formation from species in the bulk aqueous solution. Recently, a different approach, surface phase method (SP), has been developed. In SP, a thin layer including the surface is treated as a separate phase. In the bulk aqueous solution, the surface phase is treated as a virtual component, and from the chemical potential of this component, the sorption properties can be found.In the paper, we compare advantages and disadvantages of the two kinds of models. We also investigate the differences in predicted sorption properties of a number of radionuclides (Co, Np, Th and U). Furthermore, we discuss under which circumstances, one approach or the other is preferable.

Measuring Firms' Financial Constraints

2020 ◽  
pp. 276-298
Author(s):  
Carlos Carreira ◽  
João Eira ◽  
Filipe Silva
Keyword(s):  
Financial Constraints ◽  
The Other ◽  
Empirical Literature ◽  
Surprising Result ◽  
Firm Level ◽  
Advantages And Disadvantages ◽  
Indirect Measures ◽  
Large Panel ◽  
Over Time

Measuring firms' financial constraints can prove to be a difficult task for researchers because it is not possible to directly observe whether a firm is financially constrained. This chapter surveys the existing methodologies to measure such constraints at firm level, discussing the advantages and disadvantages of each one. In doing so, firstly, the authors review the direct and indirect measures of firms' financial constraints. Then they test the validity of the most commonly used indices using a large panel of (unlisted) Portuguese firms (2010-2017). The FCP index seems to outperform the other indices in capturing financial constraints of unlisted SMEs. This is not a surprising result, as most of the existing empirical literature on the field deals with listed (US) firms. It is not reasonable to expect that the coefficients of indices remain unchanged across countries and over time. Therefore, the authors propose their (re)estimation to apply them to different economies.

scholarly journals An Application of the Bishop-Simpson Method: A Shift-Share Variant

1978 ◽  
Vol 7 (1) ◽  
pp. 47-49
Author(s):  
Bruce E. Lindsay ◽  
Susan E. Martin
Keyword(s):  
New Hampshire ◽  
Regional Economy ◽  
New Technique ◽  
Fast Growing ◽  
Advantages And Disadvantages ◽  
Over Time

The Bishop-Simpson model, a variant of the traditional shift-share approach, is utilized for investigation of the development of the southern New Hampshire regional economy over time. Emphasis is placed on the strengths of the new technique in counteracting some of the limitations of traditional shift-share analyses. The B and S technique gives a clearer picture than the traditional shift-share approach of the relative advantages and disadvantages for region in terms of its specialization in slow or fast growing industries.

Blackout 2014 Exercise – Prague, the Capital of the Czech Republic

2015 ◽  
Vol 10 (2) ◽  
pp. 270-275 ◽  
Author(s):  
Tomas Hudecek ◽  
◽  
Josef Juránek ◽  
Jaroslav Pejcoch ◽  
◽  
...  
Keyword(s):  
Information Technology ◽  
Czech Republic ◽  
City Management ◽  
The Czech Republic ◽  
Advantages And Disadvantages ◽  
Rule Of Life ◽  
Analysis Of Results ◽  
Potential Damage ◽  
Over Time

As our world becomes increasingly complex over time, we are using increasingly sophisticated tools to be fed and entertained. This increasing complexity has both advantages and disadvantages. Our dependence on electric power is almost absolute and a long-term blackout could become potentially fatal to any region or country hit by it. It has been a rule of life that the intensive preparation to some crisis begins not sooner than after it strikes and causes a big damage. Prague city management did not want to wait to find out, however, and organized an exercise to understand just what such a situation might look like and just how well prepared the capital of the Czech Republic was to manage it. The exercise was designed, run and documented by up-to-date information technology, enabling further study and analysis of results to improve the city’s resilience and to prepare adequate means for mitigating potential damage.

scholarly journals Theoretic bases for the reflection on the social meaning of theoretical famous and less famous people in television

Comunicar ◽  
2005 ◽  
Vol 13 (25) ◽  
Author(s):  
María Lamuedra-Graván
Keyword(s):  
Social Meaning ◽  
Anglo Saxon ◽  
Advantages And Disadvantages ◽  
The Social ◽  
The Usa ◽  
America Latina ◽  
Siglo Xx ◽  
Medios De Comunicacion ◽  
Over Time ◽  
Sobre Todo

This article aims to set a theoretical framework for a debate about the advantages and disadvantages of the actual way in which celebrities are portrayed in Spanish television. This work deals with how fame has been present in several societies over time. The phenomenon of celebrity is placed in a context that includes the USA and Britain. The piece introduces the idea, argued by a relevant number of Anglo-Saxon authors, that fame and democracy have walked and developed together in a number of countries.q Si hay un tipo de televisión que no queremos es la que se conoce como «televisión basura». Se trata de un concepto complejo, que el Consejo Audiovisual de Cataluña (CAC) ha definido con gran habilidad. No alude, según el CAC, a un género televisivo específico, ni se limita sólo al entretenimiento, sino que se produce cuando determinados programas degradan determinados géneros vulnerando los derechos fundamentales de terceras personas o por el atropello de valores democráticos o cívicos. A continuación el consejo considera que la telebasura se encuentra básicamente concentrada en la programación denominada «del corazón», aunque matiza que el género en sí no ha de caer irremisiblemente en los despropósitos propios de la telebasura y, de hecho, reconoce que no siempre lo hace. Este trabajo aborda de manera esquemática la evolución de la fama en nuestras sociedades, y se concentra en las circunstancias socio-económicas que han hecho posible su expansión. Tal material nos permitirá proceder a una breve reflexión acerca de la representación mediática de la fama hoy en día. Precisamente porque «el corazón» no es irremisiblemente telebasura, ni debemos permitir que los despropósitos en materia cívica propios de la telebasura secuestren las potencialidades positivas del género, que las tiene. Como el propio filósofo Emilio Lledó reconoce en una entrevista con Juan Cruz sobre la fama (Cruz, 1999). En la idea de la fama hay siempre ago positivo: la lucha por el reconocimiento que es una forma peculiar de compañía y solidaridad, y de «progreso» y «movimiento de tu ser». Aunque claro está, Lledó se refiere fundamentalmente a una fama que insta a aquel que la desea a ser mejor y superarse con el propósito de ser querido. En estos últimos años la importancia de los famosos en los medios de comunicación se ha intensificado. Esto, desde luego, es perceptible en España, pero está vigente en toda Europa, incluyendo los países nórdicos (Sparre, 2003), EE.UU, América Latina, y de manera progresiva, otras zonas del globo. En el texto completo de la comunicación se ofrecen razones contundentes que ilustran la proliferación del fenómeno de los famosos en el Reino Unido, EE.UU y otras áreas del mundo como se argumentará en el texto completo de la comunicación. El interés que despiertan los famosos y la destacada presencia de éstos, sobre todo en las sociedades occidentales permite establecer cierta vinculación entre los famosos y una serie de cambios sociales económicos y culturales propios de la era moderna, democrática y capitalista. Varios investigadores ligan el progreso de ‘la cultura de la celebridad’ en el siglo XX a la democracia. Entre ellos están Leo Braudy, Victoria Price, Richard Dyer, David Marshall y Chris Rojek. La fama en sí siempre ha existido, y el deseo de celebridad también, que Leo Broudy ya achaca a Alejandro Magno varios siglos antes del nacimiento de Jesucristo. Pero para que la fama y los famosos alcancen el grado de influencia y expansión actual han de producirse una serie de cambios sociales que se han sucedido desde el desarrollo de la fotografía y las agencias de noticias. La expansión de la fama es un fenómeno de la modernidad ilustrada, así como algunas perversiones de la fama pueden analizarse como síntomas de un desequilibrio entre valores democráticos y valores mercantilistas. En resumen, la comunicación que se propone trata la fama en un contexto social y económico amplio que puede aplicarse a Europa y Estados Unidos y describe los cambios más importantes del último siglo en la forma de entender este fenómeno. Todo ello tiene el objetivo de ofrecer una perspectiva amplia desde la que reflexionar acerca de la forma actual en la que los famosos aparecen en televisión en España, y en concreto acerca de la mercantilización de la fama y de la aparición de famosos que lo son por su relación con otros y no por motivos meritocráticos.

scholarly journals Updates of Ocular Prostheses. A review of biomaterials and design in anophthalmic socket

2019 ◽  
Vol 70 (1) ◽  
pp. 239-244
Author(s):  
Claudia Florida Costea ◽  
Camelia Margareta Bogdanici ◽  
Alexandru Carauleanu ◽  
Gabriela Dimitriu ◽  
Anca Sava ◽  
...  
Keyword(s):  
Ancient Egypt ◽  
Rehabilitation Process ◽  
Ocular Prosthesis ◽  
Advantages And Disadvantages ◽  
Different Types ◽  
Orbital Tissue ◽  
Chronological Sequence ◽  
Over Time ◽  
Ocular Prostheses ◽  
Anophthalmic Socket

Since Ancient Egypt up to present day, there have constantly been attempts at creating a perfect ocular prosthesis, which would complement the outstanding deficit in the orbit as a result of enucleation, evisceration and which should be biocompatible with the orbital tissue. Over time, there have been used numerous clinical materials, which were the basis of these eye prostheses. By revising literature through the search engines PubMed, MEDLINE and other sources, this article aims at emphasizing, in a chronological sequence, the way in which different types of ocular prostheses were created, but also their advantages and disadvantages. The evolution and design of biomaterials improved the eye rehabilitation process and reduced the complications caused by these prostheses in the anophthalmic socket.

scholarly journals RESEARCH OF TIME STANDARD DEFINITION METHODS OF AIRCRAFT FASTENERS REPLACEMENT

2019 ◽  
Vol 22 (1) ◽  
pp. 18-28
Author(s):  
A. S. Solov’ev
Keyword(s):  
Experimental Method ◽  
Geometric Characteristic ◽  
Operation Time ◽  
Aircraft Design ◽  
Performance Degradation ◽  
Main Task ◽  
Advantages And Disadvantages ◽  
Time Standards ◽  
Optimized Model ◽  
Over Time

The study of the methods revealed their advantages and disadvantages for further synthesis and optimization. The main task was to improve the most suitable method, which will have the maximum number of affecting factors. The experimental method is highly accurate, but it requires high costs to work on analogues for each specific type of fasteners. The calculated method based on a single experiment allows to determine time standards for various fasteners. The given method does not require high costs for experiments, but like the experimental method, does not take into account performance degradation with continuous operation time. This leads to serious errors in obtaining time standards for a large number of fasteners. The article shows the optimized model of calculated method, based on a linear approximation of dependence of the number of fasteners replacements (removals/installations) on time at multiple intervals. The optimized model allows to obtain time standards of typical fasteners replacement with different geometric characteristic taking into account performance degradation over time. Several experiments on the aircraft were conducted for testing the improved calculated method. On the basis of the experimental data the researchers built graphs of the number of fasteners replacements (removal/installation) on time with different geometric characteristics taking into account performance degradation over time. The data obtained is advisable to use for calculation maintainability factors on aircraft design stages. Program realization of these methods and systematization of the received time standards allow to improve maintainability, due optimization number and position of airframe fasteners and systems units and aviation equipment for the aircraft being designed and modernized. Application of the automated systems of design and analysis will contribute to labor input decrease at the aircraft maintainability analysis.

Use of an Inorganic Aqueous Solution to Prevent Non-Condensable Gas Formation in Aluminum Heat Pipes

2013 ◽  
Author(s):  
Michael Stubblebine ◽  
Sean Reilly ◽  
Qi Yao ◽  
Ivan Catton
Keyword(s):  
Heat Transfer ◽  
Aqueous Solution ◽  
Heat Pipe ◽  
Heat Pipes ◽  
Solid Metal ◽  
Aluminum Surface ◽  
Working Fluid ◽  
Water Based ◽  
Inorganic Aqueous Solution ◽  
Over Time

Heat pipes are used in many applications as an effective means for transferring heat from a source to a sink. The basic heat pipe typically consists of a solid metal casing within which a working fluid is sealed inside at a given pressure. The latent heat transfer via the heat pipe’s working fluid allows it to carry a larger amount of heat energy than would normally be possible with an identically dimensioned solid metal rod. Water is often used as a working fluid due to its high heat of vaporization and suitable operating range for electronics cooling. For many applications, especially space, aluminum is desired as a casing material for its high thermal conductivity, low weight, and low cost. However, water is incompatible for use with aluminum heat pipes because it forms a non-condensable gas (NCG), hydrogen, when they contact. In this work, an inorganic aqueous solution (IAS), which has thermophysical properties similar to water, has been used as the working fluid with an aluminum alloy 5052-H2 casing. The prepared thermosiphon underwent long-term lifetime testing and the results indicate no tube failure or significant NCG formation for the duration of the 9 week study. Furthermore, the data indicate that the IAS fluid not only inhibited NCG production but also led to a reduction in heat pipe thermal resistance over time. It is believed that the chemicals in IAS react with the aluminum surface to create a compact oxide layer and electrochemical reaction which prevents hydrogen generation. A secondary, hydrophilic surface coating is also generated by the fluid on top of the first oxide (passivation) layer. This hydrophilic layer is believed to be responsible for the heat transfer enhancement which was observed during testing and the reduction in ΔT (defined as Tevap−Tcond) over time. Aluminum heat pipes used currently in practice utilize ammonia, or other non-water based working fluids, which have inferior latent heats of vaporization compared to water or an aqueous-based fluid such as IAS. The use of aluminum heat pipe casings in combination with a water-based fluid such as IAS has the potential to provide a significant increase in heat transport capability per device unit mass over traditional ammonia charged aluminum heat pipes.

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