Andrey Arbuzov - Academia.edu (original) (raw)

Papers by Andrey Arbuzov

Georesursy

This paper describes a survey conducted in an underground gas storage well that had excess annulu... more This paper describes a survey conducted in an underground gas storage well that had excess annulus pressure. The integrated well survey including Spectral Noise Logging (SNL), High Precision Temperature (HPT) Logging and pulse electromagnetic defectoscopy determined the flow geometry in the cemented annuli of the well and identified leaking tubing and casing collars. The paper provides a detailed analysis of well logging data and workover recommendations. Analysis of information on flow and leaks obtained by the survey suggested that the well did not have to be suspended.

SPE Russian Oil and Gas Exploration and Production Technical Conference and Exhibition, 2012

This paper describes the MINK tool which is based on pulsed neutron-neutron (PNN) logging technol... more This paper describes the MINK tool which is based on pulsed neutron-neutron (PNN) logging technology, its key principles and differences from other logging and data interpretation methods, and illustrates its applications to estimating oil saturation in wells. The principal feature of the MINK tool is its data recording technique in which all neutron-count decays are saved to memory and processed separately. In conventional PNN logging, 100 decays are initially accumulated and then averaged before processing, which results in information loss. Theoretical considerations and available experimental data have indicated that the probability distribution of neutrons is governed by Poisson's law [1] and allows the use of the maximum likelihood method (MLM) for experimental data fitting [2] with a substantial advantage over the conventional least-square method (LSM). This was particularly important for reservoir characterisation, as the rock's response is mainly recorded at late ti...

This paper describes the MINK tool which is based on pulsed neutron-neutron (PNN) logging technol... more This paper describes the MINK tool which is based on pulsed neutron-neutron (PNN) logging technology, its key principles and differences from other logging and data interpretation methods, and illustrates its applications to estimating oil saturation in wells. The principal feature of the MINK tool is its data recording technique in which all neutron-count decays are saved to memory and processed separately. In conventional PNN logging, 100 decays are initially accumulated and then averaged before processing, which results in information loss. Theoretical considerations and available experimental data have indicated that the probability distribution of neutrons is governed by Poisson's law [1] and allows the use of the maximum likelihood method (MLM) for experimental data fitting [2] with a substantial advantage over the conventional least-square method (LSM). This was particularly important for reservoir characterisation, as the rock's response is mainly recorded at late ti...

SPE International Oilfield Corrosion Conference and Exhibition, 2014

ABSTRACT The Magnetic Imaging Defectoscope (MID) is a tool designed to record the time response t... more ABSTRACT The Magnetic Imaging Defectoscope (MID) is a tool designed to record the time response to high-energy electromagnetic pulses. Metal presence around its sensor is detected by matching measured and numerically modelled magnetisation decays. The response in the air decays faster than if the tool is placed inside a metal pipe. If two metal pipes surround the tool, its sensors will receive their responses at different times. This phenomenon can be the key to detecting metal presence in each individual pipe. The MID tool features two sensors, short and long, to ensure reliable detection of responses from a wide range of dual-barrier completions and differentiate between defects in the first and second barriers. Despite this simple concept, the response detected by the tool has a complex time behaviour and cannot be modelled in a simple analytical way, which put time-domain technologies on hold for many years. The recent advances in computer speed and multi-core parallel computing enable accurate numerical modelling of complex responses and determining metal presence in two metal barriers separately. In addition to thickness logs, the MID tool produces colour data panels that visualise electromagnetic signatures of metal constructions and can be used to locate and recognise various completion components, such as a packer or SSD. The paper describes the basics of the time-domain magnetic-pulse technology, specifications of the tool itself and laboratory test data. This technology has been tested in a dual-string producer of the Raudhatain field operated by the Kuwait Oil Company. The long and short strings were suspected in communicating due to identical water cut trends. The MID tool was run once in memory mode on slickline through the long string and detected a 1.5-inch corrosion hole between packers that created communication with the short string. This communication flow left a footprint in a shut-in temperature log right across the corrosion hole. Another corrosion hole was located in the casing below the tubing shoe, immediately above the perforations. During a subsequent workover, the tubing was retrieved and a 1.5-inch corrosion hole was located in the exact place where it was suggested by the MID tool.

Journal of Instrumentation, 2006

Based on new data treatment methods, it is possible to identify the fitting function for the comp... more Based on new data treatment methods, it is possible to identify the fitting function for the complex permittivity ε(jω) measured for a complex system representing plant tissues of honeydew melons in the frequency range (10 7 to 1.8⋅10 9 Hz) at 25 0 C. The identified fitting function contains 9 fitting parameters and well describes the plant tissue permittivity. These parameters vary for different tissues; their correlation behavior with respect to soluble solids content (SSC), tissue density (TD) and moisture content (MC) are found by a new approach based on the statistics of the fractional moments (SFM). These correlation dependencies expressed in the form of correlation functions can be used for quality sensing of different complex systems, in particular, for ripe fruits and vegetables, where direct relationships between molecular and fitting parameters are not easy to find. These correlation functions can be used for practical purposes to construct a desired calibration curve with respect to quality factors, as for example, moisture content or degree of maturity, expressed in terms of SSC value. The discovered common "universality" in dielectric behavior of such complex materials as plant tissues opens a possibility to use dielectric spectroscopy as a nondestructive method of control in analysis of electrical behavior (measured in the form of complex permittivity or impedance) for other complex materials.

SPE Russian Oil and Gas Exploration and Production Technical Conference and Exhibition, 2012

ABSTRACT This paper presents downhole magnetic imaging defectoscopy (MID) in memory mode, its key... more ABSTRACT This paper presents downhole magnetic imaging defectoscopy (MID) in memory mode, its key principles, differences from other corrosion logging technologies, and some results of its application in oil wells. The MID technology is designed to check the integrity of magnetic and non-magnetic tubing and casing strings in oil and gas wells. It can be used to detect various defects, corrosion and mechanical wear, and to assess the quality of perforations. The MID tool contains two high-sensitivity sensors: a short generator/receiver coil and a long one with short relaxation times to analyse responses even at early times of 0.1 ms. The short coil generates a short, low-amplitude electromagnetic pulse and records a response from the first metal barrier, normally tubing, where as the long coil generates a long, high-amplitude electromagnetic pulse and records a signal travelling a much longer distance of up to 13 inches to record the total response from tubing and casing. Mathematical processing of these responses can determine the thicknesses of the first and second metal barriers. An independent power supply allows logging to be performed on slickline, which substantially reduces operating costs and enables the use of magnetic imaging defectoscopy for well monitoring to prevent leak and corrosion related incidents and thus increase environmental safety in the field. The wide use of memory magnetic imaging defectoscopy will substantially reduce the number of well incidents and expenses for remedial jobs.

SPE Russian Petroleum Technology Conference, 2015

This paper was prepared for presentation at the SPE Russian Oil & Gas Exploration & Production Te... more This paper was prepared for presentation at the SPE Russian Oil & Gas Exploration & Production Technical Conference and Exhib ition held in Moscow, Russia, 16–18 October 2012. This paper was selected for presentation by an SPE program committee following review of information contained in an abstract submitted by the author(s). Contents of the paper have not been reviewed by the Society of Petroleum Engineers and are subject to correction by the author(s). The material does not necessarily reflect any position of the Society of Petroleum Engi neers, its officers, or members. Electronic reproduction, distribution, or storage of any part of this paper without the written consent of the Society of Petroleum Engineers is prohibited. Permission to reproduce in print is restricted to an abstract of not more than 300 words; illustrations may not be copied. The abstract mus t contain conspicuous acknowledgment of SPE copyright. Abstract This paper presents downhole magnetic imaging defectos...

SPE Russian Oil and Gas Exploration and Production Technical Conference and Exhibition, 2012

SPE International Oilfield Corrosion Conference and Exhibition, 2014

ABSTRACT The Magnetic Imaging Defectoscope (MID) is a tool designed to record the time response t... more ABSTRACT The Magnetic Imaging Defectoscope (MID) is a tool designed to record the time response to high-energy electromagnetic pulses. Metal presence around its sensor is detected by matching measured and numerically modelled magnetisation decays. The response in the air decays faster than if the tool is placed inside a metal pipe. If two metal pipes surround the tool, its sensors will receive their responses at different times. This phenomenon can be the key to detecting metal presence in each individual pipe. The MID tool features two sensors, short and long, to ensure reliable detection of responses from a wide range of dual-barrier completions and differentiate between defects in the first and second barriers. Despite this simple concept, the response detected by the tool has a complex time behaviour and cannot be modelled in a simple analytical way, which put time-domain technologies on hold for many years. The recent advances in computer speed and multi-core parallel computing enable accurate numerical modelling of complex responses and determining metal presence in two metal barriers separately. In addition to thickness logs, the MID tool produces colour data panels that visualise electromagnetic signatures of metal constructions and can be used to locate and recognise various completion components, such as a packer or SSD. The paper describes the basics of the time-domain magnetic-pulse technology, specifications of the tool itself and laboratory test data. This technology has been tested in a dual-string producer of the Raudhatain field operated by the Kuwait Oil Company. The long and short strings were suspected in communicating due to identical water cut trends. The MID tool was run once in memory mode on slickline through the long string and detected a 1.5-inch corrosion hole between packers that created communication with the short string. This communication flow left a footprint in a shut-in temperature log right across the corrosion hole. Another corrosion hole was located in the casing below the tubing shoe, immediately above the perforations. During a subsequent workover, the tubing was retrieved and a 1.5-inch corrosion hole was located in the exact place where it was suggested by the MID tool.

Russian Journal of Electrochemistry, 2009

Self-similar electric circuits that represent three-dimensional models of different physical proc... more Self-similar electric circuits that represent three-dimensional models of different physical processes (phenomena of dielectric relaxation, electrochemical processes, etc.) are considered. For the first time, exact functional equations for the overall conductance (admittance) Y ( j ω ) of these resistance-capacitance circuits are derived and solved. Based on the self-similar structure of circuits, it is shown that in the frequency range, admittance represents a sum of fractional-exponential expressions with one real and a pair of complex-conjugate exponents (in further text, complex exponents). Thus, it is demonstrated that the set of processes occurring in different parts of the circuit and associated with charge transfer (capacitance C ) and elementary resistance (Ohmic resistance R ) is reduced to a fractional-exponential dependence of the ( j ωτ ) ν form. It is shown that the exponent values are related only with the parameters that determine the self-similar structure of a circuit being independent (for a large number of circuit elements) of the particular form of the elementary circuit. These exponents are also successfully related to the dynamic fractal dimension (see Eq. (2.30)), which imparts them new geometrical meaning.

Physica B: Condensed Matter, 2007

The theoretical generalization of the Jonscher's relationship for the complex conductivity of car... more The theoretical generalization of the Jonscher's relationship for the complex conductivity of carriers moving in self-similar medium is derived. It is shown that the correction derived enters to more general expression, which, in turn, we define as the generalized Jonscher's relationship. The basic idea which was used for the derivation of the relationship is based on the supposition that disordered medium has self-similar property. The derived relationship is confirmed on dielectric spectroscopy data related to sodium nitrite embedded to porous glasses. Based on new relationship there is a possibility to extract additional information about relaxation processes of a system of dipoles from the processes related to conductivity. It is important in the cases when the contribution to relaxation peaks is small and unnoticeable on the background of essential domination of processes related to conductivity.

Journal of Non-Crystalline Solids, 2007

Real time dielectric spectroscopy was used for monitoring the dynamics during liquid glass transi... more Real time dielectric spectroscopy was used for monitoring the dynamics during liquid glass transition in radical bulk polymerization of n-vinyl pyrrolidone. Two different relaxation mechanisms were identified. Initially segmental a-relaxation was dominant. Subsequently, contribution from slower motions became more significant and e 0 (t r , x) underwent maxima in all frequency bands up to 10 MHz. Peak amplitude increased and the occurring time was delayed with decreasing frequency. The slow region dynamics were similar to the dynamics of Chamberlin's domain-like model of glass transition. The glassy phase is formed by a segmental relaxation and a relaxation due to glassy regions. The characteristic relaxation times of slow and segmental motions were well described by a modified Vogel-Fulcher-Tammann relation. The high frequency behavior, associated with the segmental motions, is well described by Havriliak-Negami and Kohlrausch-Williams-Watts formulas, which did not provide satisfactory fittings for the dynamics of slow regions. Both real and imaginary parts of the dielectric data were fully described by a complex dielectric relaxation function, the parameters of which are found by the eigen-coordinates (EC) method.

Journal of Non-Crystalline Solids, 2007

Clear evidence of the existence of fractional kinetics containing the complex power-law exponents... more Clear evidence of the existence of fractional kinetics containing the complex power-law exponents were obtained by conductivity mea-12 surements of polymerization reaction of polyvinylpyrrolidone (PVP) performed inside a dielectric cell. We established the relationship 13 between the Fourier image R(jx) of the complex memory function K(t) and the time-dependent mean square displacement hr 2 (t)i. This 14 relationship helps to understand the origin of the different power-law exponents appearing in the real part of complex conductivity 15 Re[r(x)] and find a physical/geometrical meaning of the power-law exponents that can form the complex-conjugated values. The com-16 plex-conjugated values of the power-law exponents leading to oscillating behavior of conductivity follows from the fractional kinetics 17 suggested by one of the authors (R.R.N.). The relationships [R(jx) () Re[r(x)] () hr 2 (t)i] are becoming very efficient in classification 18 of different types of collective motions belonging to light and heavy carriers involved in the relaxation/transfer process. The conductivity 19 data obtained for Re[r(x)] during the whole polymerization process of the PVP at different temperatures (80, 90, 100°C) are very well 20 described by the fitting function that follows from the suggested theory. Original fitting procedure based on the application of the eigen-21 coordinates (ECs) method helps to provide a reliable fitting procedure in two stages and use the well-developed and statistically stable 22 linear least square method (LLSM) for obtaining the correct values of the fitting parameters that describe the behavior of Re[r(x, T r )] in 23 the available frequency range for the current time of the chemical reaction T r measured during the whole process of polymerization. The 24

The Journal of Chemical Physics, 2006

Dielectric spectroscopy measurements of conductivity were applied for understanding the change in... more Dielectric spectroscopy measurements of conductivity were applied for understanding the change in the internal morphology of the neutral and permanently charged polyacrylamide ͑PAAm͒ hydrogels during the swelling process. For the first time four distinct peaks ͑each corresponding to a different swelling stage͒ in the conductivity of the neutral gel were observed during the swelling of this gel. These peaks are related to the distribution of dense polymer regions ͑they are defined as the "blobs"͒ appearing in a microstructure of the given PAAm gel having at least four average sizes. For the charged gel the heterogeneity decreases due to the internal electric field of the charged sites. Thus, this characteristic behavior in the conductivity becomes almost negligible for the gel charged with permanent SO 3 − groups. It seems this fact causes considerable decrease in amplitude of the peaks and overall decrease the conductivity during the whole swelling process especially at high frequencies.

This paper describes the MINK tool which is based on pulsed neutron-neutron (PNN) logging technol... more This paper describes the MINK tool which is based on pulsed neutron-neutron (PNN) logging technology, its key principles and differences from other logging and data interpretation methods, and illustrates its applications to estimating oil saturation in wells. The principal feature of the MINK tool is its data recording technique in which all neutron-count decays are saved to memory and processed separately. In conventional PNN logging, 100 decays are initially accumulated and then averaged before processing, which results in information loss. Theoretical considerations and available experimental data have indicated that the probability distribution of neutrons is governed by Poisson's law [1] and allows the use of the maximum likelihood method (MLM) for experimental data fitting [2] with a substantial advantage over the conventional least-square method (LSM). This was particularly important for reservoir characterisation, as the rock's response is mainly recorded at late ti...

Georesursy

This paper describes a survey conducted in an underground gas storage well that had excess annulu... more This paper describes a survey conducted in an underground gas storage well that had excess annulus pressure. The integrated well survey including Spectral Noise Logging (SNL), High Precision Temperature (HPT) Logging and pulse electromagnetic defectoscopy determined the flow geometry in the cemented annuli of the well and identified leaking tubing and casing collars. The paper provides a detailed analysis of well logging data and workover recommendations. Analysis of information on flow and leaks obtained by the survey suggested that the well did not have to be suspended.

SPE Russian Oil and Gas Exploration and Production Technical Conference and Exhibition, 2012

This paper describes the MINK tool which is based on pulsed neutron-neutron (PNN) logging technol... more This paper describes the MINK tool which is based on pulsed neutron-neutron (PNN) logging technology, its key principles and differences from other logging and data interpretation methods, and illustrates its applications to estimating oil saturation in wells. The principal feature of the MINK tool is its data recording technique in which all neutron-count decays are saved to memory and processed separately. In conventional PNN logging, 100 decays are initially accumulated and then averaged before processing, which results in information loss. Theoretical considerations and available experimental data have indicated that the probability distribution of neutrons is governed by Poisson's law [1] and allows the use of the maximum likelihood method (MLM) for experimental data fitting [2] with a substantial advantage over the conventional least-square method (LSM). This was particularly important for reservoir characterisation, as the rock's response is mainly recorded at late ti...

This paper describes the MINK tool which is based on pulsed neutron-neutron (PNN) logging technol... more This paper describes the MINK tool which is based on pulsed neutron-neutron (PNN) logging technology, its key principles and differences from other logging and data interpretation methods, and illustrates its applications to estimating oil saturation in wells. The principal feature of the MINK tool is its data recording technique in which all neutron-count decays are saved to memory and processed separately. In conventional PNN logging, 100 decays are initially accumulated and then averaged before processing, which results in information loss. Theoretical considerations and available experimental data have indicated that the probability distribution of neutrons is governed by Poisson's law [1] and allows the use of the maximum likelihood method (MLM) for experimental data fitting [2] with a substantial advantage over the conventional least-square method (LSM). This was particularly important for reservoir characterisation, as the rock's response is mainly recorded at late ti...

SPE International Oilfield Corrosion Conference and Exhibition, 2014

ABSTRACT The Magnetic Imaging Defectoscope (MID) is a tool designed to record the time response t... more ABSTRACT The Magnetic Imaging Defectoscope (MID) is a tool designed to record the time response to high-energy electromagnetic pulses. Metal presence around its sensor is detected by matching measured and numerically modelled magnetisation decays. The response in the air decays faster than if the tool is placed inside a metal pipe. If two metal pipes surround the tool, its sensors will receive their responses at different times. This phenomenon can be the key to detecting metal presence in each individual pipe. The MID tool features two sensors, short and long, to ensure reliable detection of responses from a wide range of dual-barrier completions and differentiate between defects in the first and second barriers. Despite this simple concept, the response detected by the tool has a complex time behaviour and cannot be modelled in a simple analytical way, which put time-domain technologies on hold for many years. The recent advances in computer speed and multi-core parallel computing enable accurate numerical modelling of complex responses and determining metal presence in two metal barriers separately. In addition to thickness logs, the MID tool produces colour data panels that visualise electromagnetic signatures of metal constructions and can be used to locate and recognise various completion components, such as a packer or SSD. The paper describes the basics of the time-domain magnetic-pulse technology, specifications of the tool itself and laboratory test data. This technology has been tested in a dual-string producer of the Raudhatain field operated by the Kuwait Oil Company. The long and short strings were suspected in communicating due to identical water cut trends. The MID tool was run once in memory mode on slickline through the long string and detected a 1.5-inch corrosion hole between packers that created communication with the short string. This communication flow left a footprint in a shut-in temperature log right across the corrosion hole. Another corrosion hole was located in the casing below the tubing shoe, immediately above the perforations. During a subsequent workover, the tubing was retrieved and a 1.5-inch corrosion hole was located in the exact place where it was suggested by the MID tool.

Journal of Instrumentation, 2006

Based on new data treatment methods, it is possible to identify the fitting function for the comp... more Based on new data treatment methods, it is possible to identify the fitting function for the complex permittivity ε(jω) measured for a complex system representing plant tissues of honeydew melons in the frequency range (10 7 to 1.8⋅10 9 Hz) at 25 0 C. The identified fitting function contains 9 fitting parameters and well describes the plant tissue permittivity. These parameters vary for different tissues; their correlation behavior with respect to soluble solids content (SSC), tissue density (TD) and moisture content (MC) are found by a new approach based on the statistics of the fractional moments (SFM). These correlation dependencies expressed in the form of correlation functions can be used for quality sensing of different complex systems, in particular, for ripe fruits and vegetables, where direct relationships between molecular and fitting parameters are not easy to find. These correlation functions can be used for practical purposes to construct a desired calibration curve with respect to quality factors, as for example, moisture content or degree of maturity, expressed in terms of SSC value. The discovered common "universality" in dielectric behavior of such complex materials as plant tissues opens a possibility to use dielectric spectroscopy as a nondestructive method of control in analysis of electrical behavior (measured in the form of complex permittivity or impedance) for other complex materials.

SPE Russian Oil and Gas Exploration and Production Technical Conference and Exhibition, 2012

ABSTRACT This paper presents downhole magnetic imaging defectoscopy (MID) in memory mode, its key... more ABSTRACT This paper presents downhole magnetic imaging defectoscopy (MID) in memory mode, its key principles, differences from other corrosion logging technologies, and some results of its application in oil wells. The MID technology is designed to check the integrity of magnetic and non-magnetic tubing and casing strings in oil and gas wells. It can be used to detect various defects, corrosion and mechanical wear, and to assess the quality of perforations. The MID tool contains two high-sensitivity sensors: a short generator/receiver coil and a long one with short relaxation times to analyse responses even at early times of 0.1 ms. The short coil generates a short, low-amplitude electromagnetic pulse and records a response from the first metal barrier, normally tubing, where as the long coil generates a long, high-amplitude electromagnetic pulse and records a signal travelling a much longer distance of up to 13 inches to record the total response from tubing and casing. Mathematical processing of these responses can determine the thicknesses of the first and second metal barriers. An independent power supply allows logging to be performed on slickline, which substantially reduces operating costs and enables the use of magnetic imaging defectoscopy for well monitoring to prevent leak and corrosion related incidents and thus increase environmental safety in the field. The wide use of memory magnetic imaging defectoscopy will substantially reduce the number of well incidents and expenses for remedial jobs.

SPE Russian Petroleum Technology Conference, 2015

This paper was prepared for presentation at the SPE Russian Oil & Gas Exploration & Production Te... more This paper was prepared for presentation at the SPE Russian Oil & Gas Exploration & Production Technical Conference and Exhib ition held in Moscow, Russia, 16–18 October 2012. This paper was selected for presentation by an SPE program committee following review of information contained in an abstract submitted by the author(s). Contents of the paper have not been reviewed by the Society of Petroleum Engineers and are subject to correction by the author(s). The material does not necessarily reflect any position of the Society of Petroleum Engi neers, its officers, or members. Electronic reproduction, distribution, or storage of any part of this paper without the written consent of the Society of Petroleum Engineers is prohibited. Permission to reproduce in print is restricted to an abstract of not more than 300 words; illustrations may not be copied. The abstract mus t contain conspicuous acknowledgment of SPE copyright. Abstract This paper presents downhole magnetic imaging defectos...

SPE Russian Oil and Gas Exploration and Production Technical Conference and Exhibition, 2012

SPE International Oilfield Corrosion Conference and Exhibition, 2014

ABSTRACT The Magnetic Imaging Defectoscope (MID) is a tool designed to record the time response t... more ABSTRACT The Magnetic Imaging Defectoscope (MID) is a tool designed to record the time response to high-energy electromagnetic pulses. Metal presence around its sensor is detected by matching measured and numerically modelled magnetisation decays. The response in the air decays faster than if the tool is placed inside a metal pipe. If two metal pipes surround the tool, its sensors will receive their responses at different times. This phenomenon can be the key to detecting metal presence in each individual pipe. The MID tool features two sensors, short and long, to ensure reliable detection of responses from a wide range of dual-barrier completions and differentiate between defects in the first and second barriers. Despite this simple concept, the response detected by the tool has a complex time behaviour and cannot be modelled in a simple analytical way, which put time-domain technologies on hold for many years. The recent advances in computer speed and multi-core parallel computing enable accurate numerical modelling of complex responses and determining metal presence in two metal barriers separately. In addition to thickness logs, the MID tool produces colour data panels that visualise electromagnetic signatures of metal constructions and can be used to locate and recognise various completion components, such as a packer or SSD. The paper describes the basics of the time-domain magnetic-pulse technology, specifications of the tool itself and laboratory test data. This technology has been tested in a dual-string producer of the Raudhatain field operated by the Kuwait Oil Company. The long and short strings were suspected in communicating due to identical water cut trends. The MID tool was run once in memory mode on slickline through the long string and detected a 1.5-inch corrosion hole between packers that created communication with the short string. This communication flow left a footprint in a shut-in temperature log right across the corrosion hole. Another corrosion hole was located in the casing below the tubing shoe, immediately above the perforations. During a subsequent workover, the tubing was retrieved and a 1.5-inch corrosion hole was located in the exact place where it was suggested by the MID tool.

Russian Journal of Electrochemistry, 2009

Self-similar electric circuits that represent three-dimensional models of different physical proc... more Self-similar electric circuits that represent three-dimensional models of different physical processes (phenomena of dielectric relaxation, electrochemical processes, etc.) are considered. For the first time, exact functional equations for the overall conductance (admittance) Y ( j ω ) of these resistance-capacitance circuits are derived and solved. Based on the self-similar structure of circuits, it is shown that in the frequency range, admittance represents a sum of fractional-exponential expressions with one real and a pair of complex-conjugate exponents (in further text, complex exponents). Thus, it is demonstrated that the set of processes occurring in different parts of the circuit and associated with charge transfer (capacitance C ) and elementary resistance (Ohmic resistance R ) is reduced to a fractional-exponential dependence of the ( j ωτ ) ν form. It is shown that the exponent values are related only with the parameters that determine the self-similar structure of a circuit being independent (for a large number of circuit elements) of the particular form of the elementary circuit. These exponents are also successfully related to the dynamic fractal dimension (see Eq. (2.30)), which imparts them new geometrical meaning.

Physica B: Condensed Matter, 2007

The theoretical generalization of the Jonscher's relationship for the complex conductivity of car... more The theoretical generalization of the Jonscher's relationship for the complex conductivity of carriers moving in self-similar medium is derived. It is shown that the correction derived enters to more general expression, which, in turn, we define as the generalized Jonscher's relationship. The basic idea which was used for the derivation of the relationship is based on the supposition that disordered medium has self-similar property. The derived relationship is confirmed on dielectric spectroscopy data related to sodium nitrite embedded to porous glasses. Based on new relationship there is a possibility to extract additional information about relaxation processes of a system of dipoles from the processes related to conductivity. It is important in the cases when the contribution to relaxation peaks is small and unnoticeable on the background of essential domination of processes related to conductivity.

Journal of Non-Crystalline Solids, 2007

Real time dielectric spectroscopy was used for monitoring the dynamics during liquid glass transi... more Real time dielectric spectroscopy was used for monitoring the dynamics during liquid glass transition in radical bulk polymerization of n-vinyl pyrrolidone. Two different relaxation mechanisms were identified. Initially segmental a-relaxation was dominant. Subsequently, contribution from slower motions became more significant and e 0 (t r , x) underwent maxima in all frequency bands up to 10 MHz. Peak amplitude increased and the occurring time was delayed with decreasing frequency. The slow region dynamics were similar to the dynamics of Chamberlin's domain-like model of glass transition. The glassy phase is formed by a segmental relaxation and a relaxation due to glassy regions. The characteristic relaxation times of slow and segmental motions were well described by a modified Vogel-Fulcher-Tammann relation. The high frequency behavior, associated with the segmental motions, is well described by Havriliak-Negami and Kohlrausch-Williams-Watts formulas, which did not provide satisfactory fittings for the dynamics of slow regions. Both real and imaginary parts of the dielectric data were fully described by a complex dielectric relaxation function, the parameters of which are found by the eigen-coordinates (EC) method.

Journal of Non-Crystalline Solids, 2007

Clear evidence of the existence of fractional kinetics containing the complex power-law exponents... more Clear evidence of the existence of fractional kinetics containing the complex power-law exponents were obtained by conductivity mea-12 surements of polymerization reaction of polyvinylpyrrolidone (PVP) performed inside a dielectric cell. We established the relationship 13 between the Fourier image R(jx) of the complex memory function K(t) and the time-dependent mean square displacement hr 2 (t)i. This 14 relationship helps to understand the origin of the different power-law exponents appearing in the real part of complex conductivity 15 Re[r(x)] and find a physical/geometrical meaning of the power-law exponents that can form the complex-conjugated values. The com-16 plex-conjugated values of the power-law exponents leading to oscillating behavior of conductivity follows from the fractional kinetics 17 suggested by one of the authors (R.R.N.). The relationships [R(jx) () Re[r(x)] () hr 2 (t)i] are becoming very efficient in classification 18 of different types of collective motions belonging to light and heavy carriers involved in the relaxation/transfer process. The conductivity 19 data obtained for Re[r(x)] during the whole polymerization process of the PVP at different temperatures (80, 90, 100°C) are very well 20 described by the fitting function that follows from the suggested theory. Original fitting procedure based on the application of the eigen-21 coordinates (ECs) method helps to provide a reliable fitting procedure in two stages and use the well-developed and statistically stable 22 linear least square method (LLSM) for obtaining the correct values of the fitting parameters that describe the behavior of Re[r(x, T r )] in 23 the available frequency range for the current time of the chemical reaction T r measured during the whole process of polymerization. The 24

The Journal of Chemical Physics, 2006

Dielectric spectroscopy measurements of conductivity were applied for understanding the change in... more Dielectric spectroscopy measurements of conductivity were applied for understanding the change in the internal morphology of the neutral and permanently charged polyacrylamide ͑PAAm͒ hydrogels during the swelling process. For the first time four distinct peaks ͑each corresponding to a different swelling stage͒ in the conductivity of the neutral gel were observed during the swelling of this gel. These peaks are related to the distribution of dense polymer regions ͑they are defined as the "blobs"͒ appearing in a microstructure of the given PAAm gel having at least four average sizes. For the charged gel the heterogeneity decreases due to the internal electric field of the charged sites. Thus, this characteristic behavior in the conductivity becomes almost negligible for the gel charged with permanent SO 3 − groups. It seems this fact causes considerable decrease in amplitude of the peaks and overall decrease the conductivity during the whole swelling process especially at high frequencies.

This paper describes the MINK tool which is based on pulsed neutron-neutron (PNN) logging technol... more This paper describes the MINK tool which is based on pulsed neutron-neutron (PNN) logging technology, its key principles and differences from other logging and data interpretation methods, and illustrates its applications to estimating oil saturation in wells. The principal feature of the MINK tool is its data recording technique in which all neutron-count decays are saved to memory and processed separately. In conventional PNN logging, 100 decays are initially accumulated and then averaged before processing, which results in information loss. Theoretical considerations and available experimental data have indicated that the probability distribution of neutrons is governed by Poisson's law [1] and allows the use of the maximum likelihood method (MLM) for experimental data fitting [2] with a substantial advantage over the conventional least-square method (LSM). This was particularly important for reservoir characterisation, as the rock's response is mainly recorded at late ti...