Evaluation of Accuracy and Uncertainty of ISO 13503-2 Proppant Testing

2021 ◽  
Author(s):  
Galina Makashova ◽  
Stepan Yukhtarov
Keyword(s):  
Test Data ◽  
Systematic Difference ◽  
Test Methods ◽  
Interlaboratory Study ◽  
Limit Values ◽  
Testing Procedures ◽  
Well Production ◽  
The World ◽  
Acid Solubility ◽  
Key Aspects

Abstract Proppant is one of the key aspects of a successful fracturing treatment and subsequent well production, and its quality is strictly controlled by ISO 13503-2, an international standard for proppant testing. Proppant suppliers, oilfield companies and their clients all around the world rely on the standard measurement procedures and limit values to ensure the quality of a product they produce or use for fracturing operations. ISO 13503-2 prescribes testing procedures; however, the standard does not contain information about uncertainty of final measurements. This information is essential for consistent quality assurance, for resolving inconsistencies between different laboratories, and for comparing properties of different products. An interlaboratory study was organized to evaluate the precision of ISO 13503-2 proppant testing. Four proppant samples were distributed among proppant quality control laboratories all around the world; 17 laboratories participated in the study. The obtained test data were used to calculate repeatability and reproducibility standard deviations (in accordance with ISO 5725-2) and uncertainty of ISO 13503-2 test data (in accordance with ISO 21748). The study showed that most proppant parameters measured using ISO 13503-2 methods yielded high uncertainty. For example, for turbidity and acid solubility values, the uncertainty was up to ±50%. Uncertainty of roundness and sphericity values was ±0.1 since the values are estimated by operator, making the test quite subjective. For crush resistance, the highest uncertainty among tested samples, ±40%, was observed for an HSP 30/50 sample measured at 15,000 psi stress. For absolute density, a systematic difference between values obtained using gas pycnometers from different manufactures was observed; also, the equipment differs by repeatability characteristics. The results of the interlaboratory study allowed estimating the uncertainty of ISO 13503-2 test methods. It was shown that high measurement uncertainty for some critical proppant parameters should be considered for correct interpretation of the obtained test results.

KEY ASPECTS OF TRANSFORMATION OF THE STATE AUTHORITIES IN THE WORLD AND TO THE MODERN SOVERUM UKRAINE: A JOINT AND PERSONALITY

2018 ◽  
Vol 1 (11) ◽  
pp. 164-174
Author(s):  
Оlena Fedorіvna Caracasidi
Keyword(s):  
Separation Of Powers ◽  
Human Life ◽  
State Power ◽  
The State ◽  
Public Power ◽  
The People ◽  
Large Numbers ◽  
The World ◽  
Distribution Of Power ◽  
Key Aspects

The article deals with the fundamental, inherent in most of the countries of the world transformation of state power, its formation, functioning and division between the main branches as a result of the decentralization of such power, its subsidiarity. Attention is drawn to the specifics of state power, its func- tional features in the conditions of sovereignty of the states, their interconnec- tion. It is emphasized that the nature of the state power is connected with the nature of the political system of the state, with the form of government and many other aspects of a fundamental nature.It is analyzed that in the middle of national states the questions of legitima- cy, sovereignty of transparency of state power, its formation are acutely raised. Concerning the practical functioning of state power, a deeper study now needs a problem of separation of powers and the distribution of power. The use of this principle, which ensures the real subsidiarity of the authorities, the formation of more effective, responsible democratic relations between state power and civil society, is the first priority of the transformation of state power in the conditions of modern transformations of countries and societies. It is substantiated that the research of these problems will open up much wider opportunities for the provi- sion of state power not as a center authority, but also as a leading political structure but as a power of the people and the community. In the context of global democratization processes, such processes are crucial for a more humanistic and civilized arrangement of human life. It is noted that local self-government, as a specific form of public power, is also characterized by an expressive feature of a special subject of power (territorial community) as a set of large numbers of people; joint communal property; tax system, etc.

Experimental Measurement of Turbulent Diffusion, Initial Dilution and T90

1986 ◽  
Vol 18 (11) ◽  
pp. 131-140
Author(s):  
Edmundo Garcia Agudo ◽  
Jose Leomax dos Santos
Keyword(s):  
Experimental Measurement ◽  
Tracer Technique ◽  
Initial Dilution ◽  
Coastal Cities ◽  
Actual Solution ◽  
The World ◽  
Visual Aid ◽  
Proper Design ◽  
Key Aspects ◽  
Bacterial Concentrations

The final disposal of sewage using submarine outfalls has become an actual solution for coastal cities all over the world. In order to get the best results it is necessary to carry out specific studies for the proper design of the outfall. Dilution and decrease in bacterial concentrations are two key aspects for the design. Radioisotope tracers have been used extensively in studies performed in some Brazilian waterbodies where outfall systems exist or are to be installed. As far as dilution measurement is concerned, both point and continuous radiotracer injections can provide useful results. The T90 measurements can be better accomplished using a combined tracer technique for sampling the sewage field, using the radiotracer for dilution measurement and rhodamine B as a visual aid. Typical results of dilution measurement using both techniques mentioned, as well as a summary of T 90 results obtained for the Santos, Fortaleza and Maceió outfalls are presented.

Remaking Retirement

2020 ◽  
Keyword(s):  
Interest Rates ◽  
Older Workers ◽  
Older Persons ◽  
The United States ◽  
Older Population ◽  
The Past ◽  
Cost Of Education ◽  
The World ◽  
Low Interest Rates ◽  
Key Aspects

Around the world, people nearing and entering retirement are holding ever-greater levels of debt than in the past. This is not a benign situation, as many pre-retirees and retirees are stressed about their indebtedness. Moreover, this growth in debt among the older population may render retirees vulnerable to financial shocks, medical care bills, and changes in interest rates. Contributors to this volume explore key aspects of the rise in debt across older cohorts, drill down into the types of debt and reasons for debt incurred by the older population, and review policies to remedy some of the financial problems facing older persons, in the United States and elsewhere. The authors explore which groups are most affected by debt, and they also identify the factors causing this important increase in leverage at older ages. It is clear that the economic and market environments are influential when it comes to saving and debt. Access to easy borrowing, low interest rates, and the rising cost of education have had important impacts on how much people borrow, and how much debt they carry at older ages. In this environment, the capacity to manage debt is ever more important as older workers lack the opportunity to recover for mistakes.

Development of a Reproducible Method of Formulating and Testing Drilling Fluids

1969 ◽  
Vol 9 (04) ◽  
pp. 403-411 ◽  
Author(s):  
B.K. Sinha ◽  
Harvey T. Kennedy
Keyword(s):  
Large Scale ◽  
Drilling Fluid ◽  
Flow Characteristics ◽  
Field Testing ◽  
Test Methods ◽  
Water Evaporation ◽  
Fluid Loss ◽  
Drilling Fluids ◽  
Testing Procedures ◽  
Asymptotic Values

Abstract Recommendations are made for obtaining consistent and reproducible test data on drilling fluids having identical composition. Previously, such a procedure has been difficult to accomplish even when the fluids were mixed in similar equipment. A survey of work in this area indicates that previous methods have been unsatisfactory because previous methods have been unsatisfactory because (1) the muds are extremely sensitive to the duration and violence of agitation during a normal mixing routine, and (2) gelling of the muds occurs before the properties can reach constant values. This gelling is caused by water evaporation resulting from the increase in temperature associated with the agitation. The work shows that these problems largely can be overcome by (1) agitating the constituents of the drilling fluid more vigorously, (2) maintaining a fairly constant temperature, and(3) Protecting the fluid from evaporation. When these steps are followed, the fluid properties approach asymptotic values that do not change by prolonged or accelerated agitation or by aging for a month. The time required to reach asymptotic values or a stabilized state is from 2 to 6 hours and is a function of the mud composition. Introduction Preparation of drilling fluids in the laboratory to determine their suitability to meet specific drilling requirements or to serve as a base fluid to evaluate the effectiveness of thinners, dispersants or other additives normally begins with combining measured quantities of the constituents and stirring them for a short time in a low-speed mixer. This is done to obtain a uniform mixture and to hydrate clays. Then the fluid is further agitated in a higher-speed device (Hamilton Beach mixer or Waring blender) to disperse more thoroughly and clay particles The biggest obstacle in the laboratory investigation of drilling fluids has been the lack of a method of producing a mixture by which reproducible results of the measured properties could be obtained. Numerous investigators have encountered this difficulty. Prior to 1929, density was the only property of mud that customarily was measured. The use of Wyoming bentonite on a large scale after 1929 was mainly responsible for the development of more elaborate testing procedures and for the application of the principles of colloid chemistry to the drilling fluids. Ambrose and Loomis in 1931 were among the first to recognize the plastic flow characteristics of drilling fluids, although Bingham in 1916 had observed The same phenomenon with dilute clay suspensions. Marsh introduced the Marsh funnel for field testing in 1931. By this time, non-Newtonian characteristics of drilling fluids were established. The Stormer and MacMichael viscometers were used to study the rheological properties of the fluids. In the 1930's and early 1940's, the work conducted by several investigators contributed toward a better understanding of drilling fluids. In the mid 1930's, fluid-loss and the associated mud-cake-forming properties of drilling fluids were recognized as important to the behavior of these fluids. The other properties of drilling fluids, including gel strength, pH, and sand content soon were recognized. In 1937, API published its first recommended procedure for test methods. Since that time, these procedures have been revised periodically. The latest edition, RP-13B, was published in 1961 However, in spite of the recognized need for a method of mixing that provides drilling fluids with stabilized properties, no such method previously has been described. SPEJ P. 403

scholarly journals Comparison of the liquid limit of loess defined by the Vasiliev and Casagrande test methods

2021 ◽  
Vol 82 (3) ◽  
pp. 231-233
Author(s):  
Boriana Tchakalova
Keyword(s):  
Test Methods ◽  
Liquid Limit ◽  
Cone Penetrometer ◽  
Limit Values

The paper compares liquid limit values obtained by the Vasiliev and Casagrande apparatus in line with BDS 648:1984 and BDS EN ISO/ TS 17892–12:2018, on the basis of testing 25 silty loess samples. The results indicated that compared with the Vasiliev apparatus, the Casagrande apparatus gives a higher liquid limit. An equation allowing conversion of the liquid limit obtained by the Vasiliev cone penetrometer to the liquid limit by the Casagrande apparatus has been developed.

scholarly journals Tres símbolos y una metáfora en la poesía de Andrés Sánchez Robayna

2018 ◽  
pp. 90-109
Author(s):  
Alejandro Rodríguez-Refojo
Keyword(s):  
Creative Process ◽  
World View ◽  
Religious View ◽  
The World ◽  
History Of Religions ◽  
History Of ◽  
Key Aspects ◽  
Shed Light

Se analizan los símbolos de la barca, la casa y la piedra, así como la metáfora del Libro del Mundo, en la obra poética de Andrés Sánchez Robayna. El análisis se apoya en las aportaciones de la simbología y la historia de las religiones con el objetivo de esclarecer algunos aspectos clave de la cosmovisión del autor y de su poética. La presencia de imágenes pertenecientes al simbolismo del centro, la concepción de la poesía como enigma y la indagación en la memoria como una parte fundamental del proceso creador constituyen los elementos que conducen al surgimiento de una conciencia religiosa del mundo.                                                                                                                                                                                                              This paper aims to analyse three symbols presented in Andrés Sánchez Robayna’s work of poetry: the boat, the house, the stone, and the metaphor of the Book of the World. This analysis is supported by contributions in the fields of symbolism and history of religions and it seeks to shed light on some key aspects of the author’s poetics and world view. The imagery related to the symbolism of the centre, the conception of poetry as an enigma and the search through memory as an essential phase in the creative process represent the main elements which lead to the emergence of a religious view of the world.

Clinical case of type I interferonopathy: homozygous STAT2 gain-of-function mutation

2021 ◽  
Vol 20 (3) ◽  
pp. 132-139
Author(s):  
А. L. Kozlova ◽  
М. Е. Leonteva ◽  
V. I. Burlakov ◽  
Z. А. Nesterenko ◽  
О. М. Laba ◽  
...  
Keyword(s):  
Side Effects ◽  
Clinical Case ◽  
Kinase Inhibitor ◽  
Genetic Defect ◽  
Type I ◽  
Gain Of Function ◽  
The World ◽  
Key Aspects ◽  
Methods Of Treatment ◽  
Type I Interferonopathies

The article is devoted to an extremely rare variant of type I interferonopathies associated with a homozygous gain of function (GOF) mutation in the STAT2 gene in a 5-year-old child. This genetic defect was first described in 2019, and so far only 3 cases are known in the world with a similar pathology. Here we present the fourth clinical case and our experience in managing a patient with STAT2 GOF. The article presents the key aspects of the pathogenesis, clinical picture based on the analysis of all known cases of the disease. The absence of established criteria and methods of treatment for this disease is due to the rarity and relative novelty of the described nosology. We present the experience of treatment using a JAK kinase inhibitor, followed by an assessment of the effectiveness of the therapy and side effects. The patient's parents agreed to use the information, including the child's photo, in scientific research and publications.

Agent-whistleblower Technology for Secure Internet of Things

2020 ◽  
Vol 7 (1) ◽  
pp. 22-28
Author(s):  
Vladimir Eliseev ◽  
Anastasiya Gurina
Keyword(s):  
Internet Of Things ◽  
Technology Implementation ◽  
The Internet ◽  
Protective Mechanisms ◽  
Network Attacks ◽  
The World ◽  
Main Factors ◽  
Key Aspects ◽  
The Internet Of Things

  Abstract— The paper investigates the causes of widespread use by cybercriminals of the Internet of Things for organizing network attacks and other illegal use. An analysis of existing approaches and technologies for protecting networked computer devices is presented, as well as the main factors that prevent their use in the world of Internet of Things. An approach is suggested that ensures the integration of protective mechanisms directly into the composition of Things. Various variants of technology implementation are considered. Key aspects and potential ways of implementing the proposed approach are noted.Tóm tắt— Bài báo nghiên cứu về các phương thức được tội phạm mạng sử dụng rộng rãi trong Internet vạn vật (IoT), để tổ chức các tấn công mạng và các hành vi bất hợp pháp khác. Bài báo phân tích các phương pháp và công nghệ hiện có để bảo vệ các thiết bị kết nối mạng, cũng như các yếu tố chính để ngăn chặn việc sử dụng chúng trong IoT. Cách tiếp cận được đề xuất là đảm bảo việc tích hợp các cơ chế bảo vệ trực tiếp vào cấu trúc của IoT. Bài báo cũng xem xét các biến thể khác của việc thực hiện công nghệ này. Từ đó, đưa ra lưu ý về các khía cạnh chính và cách thức cài đặt tiềm năng để thực hiện phương pháp được đề xuất. 

Wings for Hummingbirds to Fly With

2017 ◽  
Author(s):  
Markus Eberl
Keyword(s):  
The Other ◽  
Ancient Maya ◽  
Symbolic Model ◽  
Knowledge Domains ◽  
Dialectical Approach ◽  
The World ◽  
Human Capacity ◽  
Key Aspects ◽  
Constituent Elements

This chapter employs the famous rabbit-duck illusion to develop a dialectical approach to change. While individuals perceive only rabbit or duck at a given moment, most, if not all, can also see the other. Switching back and forth between the rabbit and the duck creates consciousness about knowledge. This dialectical approach is applied to a symbolic model of creativity. The latter refers to the human capacity to question interpretations of the world and to find new relationships among constituent elements. Metonyms and metaphors are fundamental to human discourse and link knowledge domains in newbutincomplete ways. By hovering between domains, they build meta-awareness. The ancient Maya creator, the god Itzamnaaj, helps to illustrate key aspects of this model of creativity.

Developing Engineering Students' Communication and Information Retrieval Skills Utilizing Capstone Projects

2015 ◽  
Vol 4 (3) ◽  
pp. 1-20 ◽  
Author(s):  
Aaron S. Blicblau ◽  
Jamal Naser
Keyword(s):  
Information Retrieval ◽  
International Students ◽  
Communication Skills ◽  
Teaching And Learning ◽  
Engineering Students ◽  
Learning Approaches ◽  
The World ◽  
Computer Based ◽  
Capstone Projects ◽  
Key Aspects

The pedagogy of engineering requires a better understanding of the requirements of students' abilities to learning the skills necessary for working in the engineering community. In many engineering courses around the world, one of the key aspects required of the students is that they complete an independent project in their final year of studies incorporating information retrieval and subsequent communication skills. The current work provides details teaching and learning approaches to enhance student abilities and expertise involving research skills, communication skills, and information retrieval integrated within capstone projects. Findings from this the work indicated that both domestic and international students benefited from the intensive tutorial activities involving computer based information retrieval skills. The implementation of active tutorial sessions resulted in increased grades for the majority of students, highlighting the importance of intensive active learning events for final year capstone engineering students.

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