The book focuses on the causes of failures of oil producing pumps as a result of the aggressive action of the oil-producing environment. To ensure a good durability of the pumps, the application of laser spraying technology is investigated. Keywords: Oil Pumping Complexes, Oil Fluids, Gas Dynamic Analysis, Downhole Pumps, Calculation of Cutting Modes, Causes of Failures, Wear Mechanisms, Gas-Dynamic Calculation, Simulation Flow Software, Laser Spraying, Internal Surfaces, Electric Centrifugal Pumping, Rod Depth Pump, Non-Standard Pumps, Causes of Malfunctions, Restoring Pump Operability, Salt Deposition Inhibitors, Laser Source, Boring Head, Small-Diameter Structures.
Reflecting the significant contributions of Russian mathematicians to the field, this book contains a selection of papers on tensor and vector analysis. It is divided into three parts, covering Hamiltonian systems, Riemannian geometry and calculus of variations, and topology. The range of applications of these topics is very broad, as many modern geometrical problems recur across a wide range of fields, including mechanics and physics as well as mathematics. Many of the approaches to problems presented in this volume will be novel to the Western reader, although questions are of global interest. The main achievements of the Russian school are placed in the context of the development of each individual subject.
It was long ago that group analysis of differential equations became a powerful tool for studying nonlinear equations and boundary value problems. This analysis was especially fruitful in application to the basic equations of mechanics and physics because the invariance principles are already involved in their derivation. It is in no way a coincidence that the equations of hydrodynamics served as the first object for applying the new ideas and methods of group analysis which were developed by 1. V. Ovsyannikov and his school. The authors rank themselves as disciples of the school. The present monograph deals mainly with group-theoretic classification of the equations of hydrodynamics in the presence of planar and rotational symmetry and also with construction of exact solutions and their physical interpretation. It is worth noting that the concept of exact solution to a differential equation is not defined rigorously; different authors understand it in different ways. The concept of exact solution expands along with the progress of mathematics (solu tions in elementary functions, in quadratures, and in special functions; solutions in the form of convergent series with effectively computable terms; solutions whose searching reduces to integrating ordinary differential equations; etc. ). We consider it justifiable to enrich the set of exact solutions with rank one and rank two in variant and partially invariant solutions to the equations of hydrodynamics.
This book presents a comprehensive description of the theory and physics of high-intensity ultrasound, as well as dealing with a wide range of problems associated with the industrial applications of ultrasound, mainly in the areas of metallurgy and mineral processing. The book is divided into three sections, with Part I introducing the reader to the theory and physics of high-intensity ultrasound. Topics in this section include the propagation of ultrasound in liquid media and related nonlinear phenomena, metal crystallization in an ultrasonic field, ultrasound propagation in solids, alterations in dislocational structure, and ultrasonic effects on solidified metal. In Part II the design of ultrasonic generators, mechanoacoustic radiators and other vibrational systems is considered, as well as the control of acoustic parameters when vibrations are passed into a processed medium. Part lll describes problems associated with various uses of high-intensity ultrasound in metallurgy, for example ore dressing or producing powders and cast composites. The applications of high-intensity ultrasound for metal shaping, thermal and thermochemical treatment, welding, cutting, refining, and surface hardening are also discussed here. This comprehensive monograph provides an invaluable source of information, which has been largely unavailable in the West until now. The author is very well known and respected internationally within the field of ultrasonics.
This book is the first attempt to describe the syntax of Contemporary English exclusively in terms of dependencies (most American works on the subject being in terms of phrase structure, or constituency). The three main features of it are: (1) a fully formal presentation, (2) a reasonably complete coverage of English surface syntax, and (3) an exposition oriented towards human readers (rather than computers). The book can be recommended for several categories of readers: specialists in English syntax, linguists interested in general and theoretical syntax, computational linguists, researchers in related fields (including psychology and artificial intelligence) concerned with automatic processing (both synthesis and analysis) of English texts.
Human biological liquids contain numerous low- and high-molecular weight surfactants. The human organism contains interfaces with enormous surfaces. The physicochemical and biochemical processes taking place at these interfaces are extremely important for the vital functions of the organism as a whole, and the interfacial properties may reflect peculiarities of age and sex, health and disease. The present book is the first attempt to systematically present the results of dynamic and equilibrium surface tensions measurements of serum and urine samples that were obtained from healthy humans of various sex and age, and to compare these results with measurements of biological liquids obtained from patients suffering from various diseases or with measurements of amniotic fluid obtained from women at various stages of pregnancy.Pulmonary medicine, especially neonatology, has systematically used interfacial tensiometry for studying pulmonary surfactant. In this particular area, significant progress was achieved in the treatment of diseases related to alterations of the lung surfactant system. We believe that, similar to the progress in pulmonary medicine attributed to surface chemical studies of lung surfactant, progress in other medical branches could be expected through studies of interfacial characteristics of other human biological liquids.For several years the authors of this book have been engaged in studies aimed at the improvement of the maximum bubble pressure method, resulting in the development of computer controlled tensiometers which are capable of measuring dynamic surface tensions within a wide range of surface lifetime. In addition to the measurement techniques, a correct interpretation and analysis of the tensiometric data obtained is extremely important. The kinetic theory of adsorption from solutions, and the theory of equilibrium adsorption layers of surfactant/protein mixtures provide the basis for both the choice of the most characteristic parameters of tensiograms and the analysis of the results. Some theoretical models describing the adsorption of proteins are presented in Chapter 1. The main theoretical and experimental issues related to the maximum bubble pressure technique as applied to biological liquids are presented in Chapter 2. A more detailed discussion of the differences of the various methods in use for measuring dynamic surface tension of biological fluids is provided in Chapter 3. Chapter 4 gives data from patients with kidney disease, Chapter 5 from patients with rheumatic diseases, Chapter 6 with pulmonary diseases, Chapter 7 with diseases of the central nervous system, and Chapter 8 with neoplasms.Dynamic interface tensiometry of human biological liquids is a fascinating new method which deserves a broad use for prospective studies of various diseases.
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