Journal articles: 'Electric self potential'

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Skianis, Georgios Ai, and M. Carmen Hernández. "Effects of transverse electric anisotropy on self-potential anomalies." Journal of Applied Geophysics 41, no. 1 (1999): 93–104. http://dx.doi.org/10.1016/s0926-9851(98)00052-4.

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Fachin, Sergio J. S., Eduardo L. Abreu, Carlos A. Mendonça, André Revil, Guilherme C. Novaes, and Suzan S. Vasconcelos. "Self-potential signals from an analog biogeobattery model." GEOPHYSICS 77, no. 4 (2012): EN29—EN37. http://dx.doi.org/10.1190/geo2011-0352.1.

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A tank experiment was conducted to check if self-potential (SP) signals can be generated when buried organic matter is wire-connected to a near-surface, oxygen-rich, sediment layer. This experiment demonstrated that once wired, there was a flux of electrons (hence an electric current) between the lower and upper layers of the sandbox with the system responding as a large-scale microbial fuel cell (a type of bioelectrochemical system). An electric current was generated by this process in the wire and the SP method was used to monitor the associated electric potential distribution at the top of the tank. The electric field was controlled by the flux of electrons through the wire, the oxidation of the organic matter, the reduction of oxygen used as a terminal electron acceptor, and the distribution of the DC resistivity in the tank. The current density through the wire was limited by the availability of oxygen and not by the oxidation of the organic matter. This laboratory experiment incorporated key elements of the biogeobattery observed in some organic-rich contaminant plumes. This analogy includes the generation of SP signals associated with a flux of electrons, the capacity of buried organic matter in sustaining anodic reactions, network resistance connecting terminal redox reactions spatially separated in space, and the existence of anodic secondary coupled reactions. A resistivity tomogram of the tank, after almost a year in operation, suggests that oxidative processes triggered by this geobattery can be imaged with this method to determine the radius of influence of the bioelectrochemical system.

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Heinze, T., JK Limbrock, SP Pudasaini, and A. Kemna. "Relating mass movement with electrical self-potential signals." Geophysical Journal International 216, no. 1 (2018): 55–60. http://dx.doi.org/10.1093/gji/ggy418.

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SUMMARY Landslides present a latent danger to lives and infrastructure worldwide. Often such mass movements are caused by increasing pore pressure. The electrical self-potential (SP) method has been applied in a broad range of monitoring studies. When fluid flow is involved the most relevant source of SP is the streaming potential, caused by the flow of an electrolyte through porous media with electrically charged internal surfaces. We experimentally investigated the SP signal associated with deformation of partially saturated soil. For partly saturated scenarios, we observed an SP signature correlated with the mass movement. In dry experiments, we did not observe any significant change in the electric signal. Results of numerical simulations match with the experimental observations when assuming a local and temporary alteration of the hydraulic pressure due to the sliding mass. Our findings suggest that SP measurements can be used to observe mass movement triggered by fluid pressure variations through the streaming potential.

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Parsons, Michael G., David J. Singer, and Samuel J. Denomy. "Integrated Electric Plants in Future Great Lakes Self-Unloaders." Journal of Ship Production and Design 27, no. 04 (2011): 169–85. http://dx.doi.org/10.5957/jspd.2011.27.4.169.

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The feasibility and potential benefits of using Integrated Electric Plants in future Great Lakes self-unloaders are evaluated. Integrated Electric Plants, the all-electric ships, utilize electrical propulsion motors and central station power generation that powers all propulsion, thruster, self-unloading equipment, and other ship service needs. Integrated Electric Plants have become the plant of choice in many recent naval vessels, cruise ships, high technology cargo vessels, and special purpose vessels, such as offshore supply and service vessels and icebreakers. This study considers arrangements, effects on cargo capacity, fuel usage, and environmental emissions in all operating modes, maintenance requirements, and manning. The comparison is made for two notional self-unloading bulk carriers: a 1000 ft Poe Lock maximum self-unloader and a 730 ft MacArthur Lock, Welland Canal, St. Lawrence Seaway maxi-mum self-unloader.

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Thanh, Luong Duy, Nguyen Canh Thai, Nguyen Manh Hung, Nguyen Cong Thang, and Luong Thi Thanh Huong. "SELF-POTENTIAL METHOD FOR DETECTION OF WATER LEAKAGE THROUGH DAMS." Earth Science Malaysia 4, no. 2 (2020): 152–55. http://dx.doi.org/10.26480/esmy.02.2020.152.155.

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The self-potential (SP) method is a passive, non-invasive and cost-effective geophysical method based on the measurement of electrical potential naturally occurring on the earth’s surface. One of the main causes for the electrical potential at the earth’s surface is water seepage under the ground. In this work, we perform the SP measurement on a small artificial earthen dam built at Thuyloi University. Our result shows that the selection of electrode types is crucial in the SP measurements. Namely, Cu/CuSO4 porous pots are much better than copper stake electrodes for the SP measurement. Additionally, it is shown that the SP measurement using suitable electrodes can be applied to detect underground water leakage and flow direction in the dam based on an anomaly and variation of electric potential with position on the survey area.

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Toko, Kiyoshi, Masaru Tsukiji, Satoru Iiyama, and Kaoru Yamafuji. "Self-sustained oscillations of electric potential in a model membrane." Biophysical Chemistry 23, no. 3-4 (1986): 201–10. http://dx.doi.org/10.1016/0301-4622(86)85004-9.

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Sakai, Hideo, Takeshi Kato, Hitoshi Sakurano, Tomo-o. Ushio, and Zen-ichiro Kawasaki. "Study of high frequency change in Electric Self-Potential at Lightning." IEEJ Transactions on Power and Energy 119, no. 8-9 (1999): 966–72. http://dx.doi.org/10.1541/ieejpes1990.119.8-9_966.

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Ojovan, Michael I., Boris E. Burakov, and William E. Lee. "Destruction of Micro-crystal Containing Wasteforms by Charge-induced Crystal Shape Change on Self-irradiation." MRS Advances 2, no. 11 (2016): 621–26. http://dx.doi.org/10.1557/adv.2016.655.

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ABSTRACTMechanical damage of non-metallic nuclear wasteforms can be caused by electrical fields induced by decaying clusters of radionuclides surrounded by an insulating matrix. We assess the electric fields near clusters with decaying radionuclides 244Cm, 241Am, 238,239Pu and 137Cs in a glass matrix determining that matrix destruction can gradually occur via electric breakdown discharges and diffusion-controlled change in form of clusters. The most important parameters that control potential matrix destruction are the radioactive cluster (inhomogeneity) size, radionuclide specific radioactivity and effective electrical conductivity of the matrix.

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De Keyser, J., and M. Echim. "Electric potential differences across auroral generator interfaces." Annales Geophysicae 31, no. 2 (2013): 251–61. http://dx.doi.org/10.5194/angeo-31-251-2013.

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Abstract. Strong localized high-altitude auroral electric fields, such as those observed by Cluster, are often associated with magnetospheric interfaces. The type of high-altitude electric field profile (monopolar, bipolar, or more complicated) depends on the properties of the plasmas on either side of the interface, as well as on the total electric potential difference across the structure. The present paper explores the role of this cross-field electric potential difference in the situation where the interface is a tangential discontinuity. A self-consistent Vlasov description is used to determine the equilibrium configuration for different values of the transverse potential difference. A major observation is that there exist limits to the potential difference, beyond which no equilibrium configuration of the interface can be sustained. It is further demonstrated how the plasma densities and temperatures affect the type of electric field profile in the transition, with monopolar electric fields appearing primarily when the temperature contrast is large. These findings strongly support the observed association of monopolar fields with the plasma sheet boundary. The role of shear flow tangent to the interface is also examined.

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10

Urabe, Kei, and Hiroshi Sakaguchi. "Electric current induced self-sustained oscillation of electric potential across a membrane filter impregnated with triolein." Chemical Physics Letters 176, no. 3-4 (1991): 361–65. http://dx.doi.org/10.1016/0009-2614(91)90044-a.

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11

Watts, Bernard. "Chemical segregation and self polarisation in ferroelectrics." Processing and Application of Ceramics 3, no. 1-2 (2009): 97–101. http://dx.doi.org/10.2298/pac0902097w.

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Chemical partitioning or segregation is commonly encountered in solid-state syntheses. It is driven by compositional, thermal and electric field gradients. These phenomena can be quite extreme in thin films and lead to notable effects on the electrical properties of ferroelectrics. The segregation in ferroelectric thin films will be illustrated and the mechanisms explained in terms of diffusion processes driven by a potential gradient of the oxygen. The hypothesis can also explain self polarisation and imprint in ferroelectric hysteresis. .

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Astrakhantsev, Leonid, Natalya Ryabchyonok, Tatyana Alekseeva, Andrey Khomenko, and Aleksey Martusov. "Energy-efficient power regulators for electric railway vehicles." MATEC Web of Conferences 216 (2018): 02001. http://dx.doi.org/10.1051/matecconf/201821602001.

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This study aims at validation of the power regulation parameter for electric railway vehicles for effective use of electrical potential of energy sources. Based on analysis of electromagnetic processes with the use of suggested energy parameters and mathematical modeling method the assessment of energy efficiency was performed for semiconductor power regulators for alternating and direct current electric traction drives. Power balance and obtained mathematical equations for calculation of its components allow improving the education content of educational institutions due to eliminating methodological inconsistencies. The suggested technical solutions for continuous and full use of the electrical potential of overhead systems and self-generated power supply sources ensure their advantage in terms of structure, energy efficiency and electromagnetic compatibility.

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Bartolini, Andrea, Gabriele Comodi, Danilo Salvi, and Poul Alberg Østergaard. "Renewables self-consumption potential in districts with high penetration of electric vehicles." Energy 213 (December 2020): 118653. http://dx.doi.org/10.1016/j.energy.2020.118653.

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Sakai, Hideo, Tsuyoshi Kobayashi, Yoshinori Izumi, Takeshi Nakayama, and Katsumi Hattori. "Induced Change of Electric Self-potential and Magnetic Field at the Artificial Explosion." IEEJ Transactions on Fundamentals and Materials 136, no. 5 (2016): 291–96. http://dx.doi.org/10.1541/ieejfms.136.291.

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SAKAI, HIDEO, TSUYOSHI KOBAYASHI, YOSHINORI IZUMI, TAKESHI NAKAYAMA, and KATSUMI HATTORI. "Induced Change of Electric Self-Potential and Magnetic Field at the Artificial Explosion." Electronics and Communications in Japan 100, no. 3 (2017): 68–75. http://dx.doi.org/10.1002/ecj.11942.

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AIZAWA, K., R. YOSHIMURA, N. OSHIMAN, et al. "Hydrothermal system beneath Mt. Fuji volcano inferred from magnetotellurics and electric self-potential." Earth and Planetary Science Letters 235, no. 1-2 (2005): 343–55. http://dx.doi.org/10.1016/j.epsl.2005.03.023.

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Hasan, Muhammad Fathur Rouf, Tri Widya Swastika, Nunung Martina, and Linda Sari Wulandari. "IDENTIFICATION OF GROUNDWATER DISTRIBUTION USING SELF POTENTIAL METHOD." Applied Research on Civil Engineering and Environment (ARCEE) 1, no. 01 (2019): 16–23. http://dx.doi.org/10.32722/arcee.v1i01.1953.

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Drought is one of the biggest problems for the community, this problem will be slightly resolved by the compilation of regions with groundwater sources. This research has been carried out in the karst area, Druju Village, Sumbermanjing District, Wetan Regency, Malang. The purpose of this study is to determine the distribution of underground air and the pattern between underground rivers in the Wonorejo draw well and spring sources in the Kaligoro River, Wonorejo Hamlet.The method that used is the Self Potential (SP) method to set the moving electrode (leap frop) with 104 measurement points. The results of this study indicate the value of electric potential shown between 0-13.5 mV, and assume that a low potential value (0-1 mV) is an indication of groundwater distribution. Areas with low potential values are found in the empathy area. When taking a distribution of water on the surface of the land that appears through the Kaligoro River, it does not need to go out in one stream with an underground river flowing in the wells of the residents. The area with the lowest potential value is a reference in making wells

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Ikard, Scott J., Andrew P. Teeple, Jason D. Payne, Gregory P. Stanton, and J. Ryan Banta. "New Insights on Scale-dependent Surface-Groundwater Exchange from a Floating Self-potential Dipole." Journal of Environmental and Engineering Geophysics 23, no. 2 (2018): 261–87. http://dx.doi.org/10.2113/jeeg23.2.261.

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In south-central Texas the lower Guadalupe River has incised into the outcrop of the Carrizo-Wilcox aquifer. The river and the aquifer are hydraulically connected across the outcrop, although the connectivity is obscured at the surface by alluvium and surface-water and groundwater exchange dynamics are currently poorly understood. To investigate surface-water and groundwater exchange dynamics between the lower Guadalupe River and the Carrizo-Wilcox aquifer, a geophysical study was completed along a 14.86 km reach of the river by using water-borne gradient self-potential (SP) profiling and two-dimensional direct-current electric resistivity tomography. This paper explores the applicability of these water-borne geoelectric methods in delineating gaining and losing channel reaches, and demonstrates that geoelectric signals in the form of total electric field strength can be logged with an electric dipole and decomposed into component SP signals depicting regional and local groundwater flow patterns attributable to regional and localized hydraulic gradients. Localized SP anomalies of several tens of millivolts, indicative of hyporheic exchange flows, are observed and superimposed upon a 124 mV regional SP anomaly indicative of ambient groundwater exchange flows between the river and the aquifer. The observed SP signals are interpreted through two-dimensional finite-element modeling of streaming potentials attributable to ambient groundwater exchange and hyporheic exchange flow patterns. Variables of the channel environment such as temperature and concentration gradients, depth, and velocity are considered and subsequently eliminated as alternative sources of the SP signals that are presented.

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Flores-Márquez, L., J. Márquez-Cruz, A. Ramírez-Rojas, G. Gálvez-Coyt, and F. Angulo-Brown. "A statistical analysis of electric self-potential time series associated to two 1993 earthquakes in Mexico." Natural Hazards and Earth System Sciences 7, no. 5 (2007): 549–56. http://dx.doi.org/10.5194/nhess-7-549-2007.

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Abstract. Recent studies related with earthquake prediction involve statistical studies of the ground electric self-potential behavior. Published results about the complexity of this kind of processes encourage us to study the statistical behavior of the ground electric self-potential recorded in Guerrero state, Mexico. This region is characterized by high seismicity. The electric self-potential variations were recorded in the Acapulco station directly from the ground. The sampling period was four seconds and the data were stored from March to December of 1993. Two significant earthquakes (EQs) occurred near this station, 15 May and 24 October whose magnitudes were Mw=6.0 and Mw=6.6 respectively. A preliminary processing was carried out consisting of a moving average of the original time series in order to filter the very high frequencies and to complete short lacks of data and outliers. Then, a visual inspection of the complete filtered signal was performed to search some seismic electric signals (SES), which were ambiguously depicted. Subsequently, a detrending of µ=0 was applied with the windows of 3.3, 6.6 and 10 h. Later, the analysis of the spectral exponent β was made, showing changes during the total period examined, and the most evident changes occurred during the preparation mechanism of the Mw=6.6 EQ. Fifteen days before the 24 October EQ, a Brownian-noise like behavior was displayed (β≈2), having a duration of about two days. In addition a Higuchi fractal method and wavelet analysis were made confirming the presence of the β-anomaly.

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Scolfaro, L. M. R., R. P. Camata, J. M. V. Martins, and J. R. Leite. "Influence of electric fields in the Si delta-doped GaAs self-consistent potential profile." Superlattices and Microstructures 12, no. 2 (1992): 203–6. http://dx.doi.org/10.1016/0749-6036(92)90337-5.

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Vasconcelos, Suzan S., Carlos A. Mendonça, and Nilton Silva. "Self-potential signals from pumping tests in laboratory experiments." GEOPHYSICS 79, no. 6 (2014): EN125—EN133. http://dx.doi.org/10.1190/geo2013-0444.1.

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Streaming potentials can be generated when geologic porous media are subjected to pumping tests. For a homogeneous medium, theory predicts that input and output points for water circulation generate field responses in the form of electric potentials that are equivalent to those produced by current sources that are externally driven by a power source. We evaluated tank experiments showing that this assumption is valid for common geophysical scenarios and can be used to determine charge density for porous geologic media, a key parameter in interpreting electrokinetic and interfacial properties in hydrogeophysics. We also determined that when water circulation encompasses a heterogeneity, the equivalence with single current poles is lost, and this can be used as a field criterion to detect inhomogeneities near a well. Our experimental results were analyzed with finite-element modeling of water and charge flow, showing that an interfacial distribution of currents must be expected as the cause of distortions in self-potential fields. We developed a procedure that used the background resistivity model to better image the distribution of currents onto media interfaces, pointing out advances still needed and challenges still remaining to improve source imaging.

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Yang, Cai, Shengdong Liu, and Haiping Yang. "Self-potential response characteristics of red sandstone samples under uniaxial compression." Journal of Geophysics and Engineering 16, no. 4 (2019): 742–52. http://dx.doi.org/10.1093/jge/gxz044.

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Abstract Deformation and rupture of rock mass under loading cause the variation of electric potential. Response characteristics of self-potential and stress during the complete stress-strain process of red sandstones play an important role in evaluating the stress state of sandstone on the basis of self-potential. Experimental results demonstrate that the stress of red sandstone under uniaxial compression is linearly correlated with the self-potential difference before the first inflection point in the initial stage of loading. The average variation rate of self-potential difference and stress is 0.1325 mV MPa−1. As the loading pressure gradually increases and enters the softening stage (before the maximum loading point), the catastrophic points of uniaxial loading stress correspond to the inflection point of self-potential. The self-potential of red sandstone varies in a range of 0–45.6 mV in that case and it fluctuates most significantly around the maximum loading point, with a range of 0.3–195.5 mV. In the end stage of loading, the macroscopic rupture of the red sandstone sample is complete, the self-potential of red sandstone fluctuates slightly around the maximum load point and then gradually stabilizes. Moreover, it is found that self-potentials change more significantly in the radial direction than in the axial direction in the uniaxial compression experiment, indicating that self-potentials generated by rock mass rupture are more sensitive in the radial direction. The rupture process of red sandstone can be dynamically represented by the tempo-spatial evolution profiles of self-potential.

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Khusnutdinov, N. "Self-force and the Huygens principle." International Journal of Modern Physics A 35, no. 02n03 (2020): 2040016. http://dx.doi.org/10.1142/s0217751x20400163.

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We consider a relation between the Huygens Principle (HP) in gravity and the self-interaction force. We show that the self-force for an electric particle in the plane gravitational wave space-time has no tail term even the vector Green function does not obey the HP. The reason for this observation is that even vector potential does not obey the HP, the electromagnetic field does obey.

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Aleshkov, M. V., D. A. Ioshchenko та I. A. Olkhovsky. "Various electrical ﬁres and ﬁreﬁghting methods". Pozharovzryvobezopasnost/Fire and Explosion Safety 29, № 5 (2020): 51–59. http://dx.doi.org/10.22227/pvb.2020.29.05.51-59.

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Introduction. Fires of voltage-carrying electrical units are most dangerous and difﬁcult to put out. Personnel of ﬁre emergency response units are at high risk of electric shock when extinguishing such ﬁres. Electrical units have recently obtained a new are of application, that is, electric cars. Electric car design entails the use of high-capacity batteries and high voltage electrical equipment, which pose a higher ﬁre hazard. The objective of this article is to analyze potential assets to be protected and assess existing electrical ﬁre extinguishing methods to substantiate principal areas of research into design of safe ﬁre extinguishing systems designated for electrical units installed on motor vehicles.Main (Analytical) part. The ﬁre extinguishing of the items, that have electrical units to be extinguished without any electricity outage, must be performed by the ﬁre departments that have appropriately trained and equipped personnel. However, in the event of an electric car ﬁre, it is impossible to forecast which ﬁre department will be nearby and how well it will be equipped. The design features of electric vehicles show that potential sources of the ﬁre hazard include lithium batteries and electrical circuit elements. These factors explain the need to consider the problem of extinguishing self-contained electrical ﬁres inside motor vehicles from the standpoint of electrical safety. It is suggested to identify the ﬁre extinguishing method in furtherance of the analysis of a set of principal ﬁre extinguishing methods with regard for the design of efﬁcient ﬁreﬁghting appliances that ensure safe extinguishing of electric car ﬁres.Conclusions. It is expedient to use the pulse application of a ﬁre-extinguishing agent that prevents current leakage while extinguishing various types of electrical appliances, including those installed on motor vehicles. The effects of exothermic reactions, involving lithium-containing elements, were not analyzed when solving this problem. This research will serve as the basis for conceptual technological solutions designated for ﬁre emergency response units responsible for extinguishing electric car ﬁres.

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Gottwald, Martin, and Gerhard von der Emde. "Bio-Inspired Active Electrolocation Sensors for Inspection of Tube Systems." Advances in Science and Technology 84 (September 2012): 45–50. http://dx.doi.org/10.4028/www.scientific.net/ast.84.45.

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At night, weakly electric fish Gnathonemus petersii use active electrolocation to scan their environment with self generated electric fields. Nearby objects distort the electric fields and are recognized as electric images on the electroreceptive skin surface of the animal. By analyzing the electric image, G. petersii can sense an object’s distance, dimensions and electrical properties. The principles and algorithms of active electrolocation can be applied to catheter-based sensor systems for analysing wall changes in fluid filled tube systems, for example atherosclerotic plaques of the coronary blood vessels. We used a basic atherosclerosis model of synthetic blood vessels and plaques, which were scanned with a ring electrode catheter applying active electrolocation. Based on the electric images of the plaques and the evaluation of bio-inspired image parameters, the plaque’s fine-structure could be assessed. Our results show that imaging through active electrolocation principally has the potential to detect and characterize atherosclerotic lesions.

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Rittgers, J. B., A. Revil, M. Karaoulis, M. A. Mooney, L. D. Slater, and E. A. Atekwana. "Self-potential signals generated by the corrosion of buried metallic objects with application to contaminant plumes." GEOPHYSICS 78, no. 5 (2013): EN65—EN82. http://dx.doi.org/10.1190/geo2013-0033.1.

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Large-amplitude ([Formula: see text]) negative electric (self)-potential anomalies are often observed in the vicinity of buried metallic objects and ore bodies or over groundwater plumes associated with organic contaminants. To explain the physical and chemical mechanisms that generate such electrical signals, a controlled laboratory experiment was carried out involving two metallic cylinders buried with vertical and horizontal orientations and centered through and in the capillary fringe within a sandbox. The 2D and 3D self-potential (SP) data were collected at several time steps along with collocated pH and redox potential measurements. Large dipolar SP and redox potential anomalies developed in association with the progressive corrosion of the vertical pipe, although no anomalies were observed in the vicinity of the horizontal pipe. This discrepancy was due to the orientation of the pipes with the vertical pipe subjected to a significantly larger [Formula: see text] gradient. Accounting for the electrical conductivity distribution, the SP data were inverted to recover the source current density vector field using a deterministic least-squares 4D (time-lapse) finite-element modeling approach. These results were then used to retrieve the 3D distribution of the redox potential along the vertical metallic cylinder. The results of the inversion were found to be in excellent agreement with the measured distribution of the redox potential. This experiment indicated that passively recorded electrical signals can be used to nonintrusively monitor corrosion processes. In addition, vertical electrical potential profiles measured through a mature hydrocarbon contaminated site were consistent with the sandbox observations, lending support to the geobattery model over organic contaminant plumes.

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Safipour, Roxana, Sebastian Hölz, Jesse Halbach, Marion Jegen, Sven Petersen, and Andrei Swidinsky. "A self-potential investigation of submarine massive sulfides: Palinuro Seamount, Tyrrhenian Sea." GEOPHYSICS 82, no. 6 (2017): A51—A56. http://dx.doi.org/10.1190/geo2017-0237.1.

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The self-potential (SP) method detects naturally occurring electric fields, which may be produced by electrically conductive mineral deposits, such as massive sulfides. Recently, there has been increasing interest in applying this method in a marine environment to explore for seafloor massive sulfide (SMS) deposits, which may contain economic resources of base and precious metals. Although SMS sites that are associated with active venting and are not buried under sediment cover are known to produce an SP signal, the effectiveness of the method at detecting inactive and sediment-covered deposits remained an outstanding question. We built an instrument capable of recording SP data in a marine setting. We carried out a test of the instrument at the Palinuro Seamount in the Tyrrhenian Sea. Palinuro is one of only a few known sites containing an SMS occurrence that is buried under sediment and not associated with active hydrothermal venting, although diffuse seepage of hydrothermal fluids is known to occur at the site. Elevated electric field strengths recorded in and near the site of previously drilled massive sulfide samples are on the order of [Formula: see text]. A second zone of high field strengths was detected to the north of the drilling area where gravity coring later confirmed the existence of massive sulfides. Our observations indicate that an SP signal can be observed at the site of SMS mineralization even when the mineralized zone is shallowly buried and active hydrothermal venting is not present. These observations could aid in the planning of future marine research expeditions that use the SP method in the exploration of seafloor massive sulfides.

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Salnikov, Mikhail, Alexander Fedoseev, and Gennadiy Sukhinin. "Plasma Parameters around a Chain-Like Structure of Dust Particles in an External Electric Field." Molecules 26, no. 13 (2021): 3846. http://dx.doi.org/10.3390/molecules26133846.

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The formation of a 1D chain-like structure of dust particles in a low-temperature argon plasma was studied. A new numerical model for calculation of the self-consistent spatial distribution of plasma parameters around a chain of dust particles was presented. The model described the motion of positively charged ions in the electric potential of several negatively charged dust particles, taking into account the action of an external electric field. The main advantage of the model was that the charges of the dust particles and the interparticle distances were determined self-consistently. As a result of numerical simulations, the dependencies of the spatial distributions of the plasma parameters (the densities of electrons and ions and the self-consistent electric potential) near the dust particles chain on the strength of the external electric field, an external force acted on the last particle, and the mean free path of the ions was determined. The obtained results made it possible to describe the process of the formation of chain-like structures of dust particles in discharge plasma.

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Baag, Czango, and Deok Kyo Lee. "Absence of magnetic anomalies due to seepage‐induced “magnetoelectric effects” and implications for sulfide self‐potentials." GEOPHYSICS 54, no. 9 (1989): 1174–79. http://dx.doi.org/10.1190/1.1442752.

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The magnetic field due to an azimuthally symmetric distribution of subsurface electric current, which may be associated with vertical hydrocarbon seepage, vanishes above the ground surface. However, geologic conditions in general do not provide perfect isotropic conditions, and, in theory, some magnetic fields can be generated by the magnetoelectric effect. Sedimentary rock sections are relatively isotropic, particularly in the stratigraphic plane. Thus, hydrocarbon seepage‐induced magnetic fields above the ground surface may never be significant, even if strong electric currents are associated with the seepage. All current‐generated magnetic fields, of whatever origin, must obey Ampère’s law; no line integral operation can distinguish a magnetic field having one origin from that of any other origin. Therefore, seepage‐induced magnetic anomalies, if they exist at all, are probably useless for hydrocarbon exploration because it is virtually impossible to distinguish them from other anomalies of unknown origin. Thus, even if hydrocarbon seepage is capable of producing oxidized and reduced zones, the significance of any generated electric currents is very doubtful. Since the seepage‐induced electrochemical model lacks a conducting mass in the columnar reducing zone and/or an electric barrier around the reducing zone, electric potential due to excess electric charges developed between the two zones would tend to dissipate.

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Misnikov, Oleg. "Study of Peat Fillers for their Potential Use in Electric Energy Storage Devices." E3S Web of Conferences 278 (2021): 01022. http://dx.doi.org/10.1051/e3sconf/202127801022.

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The article discusses the pros and cons of modern devices for power accumulating and its storage (supercapacitors). The author analyses porous carbon materials traditionally used as fillers in such devices. The presented main physical and chemical properties of peat allow the author to propose a working hypothesis about the possibility of using peat sorbents in supercapacitors. This is possible due to the high specific surface area of peat and by the presence of particles with a double electric layer (micelles) in it. For the first time ever, it was experimentally established that the use of a bog peat sorbent instead of activated carbon as a porous material makes it possible to multiply the voltage during self-discharge of an experimental model of a supercapacitor. The size of the peat sorbent fractions does not significantly affect the self-discharge process. However, there is a slight improvement in the performance of the device when using the fractions under 1.25 mm. The use of peat raw materials with a high degree of decomposition significantly improves the characteristics of the experimental model at a charging voltage of 10 V.

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Toko, Kiyoshi, Naotoshi Nakashima, Satoru Iiyama, Kaoru Yamafuji, and Toyoki Kunitake. "Self-Oscillation of Electric Potential of a Porous Membrane Impregnated with Polymer Multi-Bilayer Complexes." Chemistry Letters 15, no. 8 (1986): 1375–78. http://dx.doi.org/10.1246/cl.1986.1375.

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Garcia, Cristobal, Irina Trendafilova, Roberto Guzman de Villoria, and Jose Sánchez del Río. "Triboelectric nanogenerator as self-powered impact sensor." MATEC Web of Conferences 148 (2018): 14005. http://dx.doi.org/10.1051/matecconf/201814814005.

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In recent years, triboelectric nanogenerators (TENGs) are used to harvest mechanical energy from ambient environment. These devices convert ambient energies (e.g. vibrations, breathing-driven, impacts or human body motions) into electricity based on the triboelectric effect. Furthermore, some TENGs can be successfully employed as self-power active sensors because the electric response from the TENG is proportional to the magnitude of the mechanical motion. This study report on the design and development of a novel triboelectric nanogenerator, and its potential application as self-powered impact sensor. To prepare the TENG device, membranes of polyvinylidene fluoride (PVDF) and polyvinylpyrrolidone (PVP) nanofibers are sandwiched between copper electrode films and wrapped on PET films. The TENG works based on the triboelectric interaction between the membranes of nanofibers. After the preparation, the TENGs are subjected to several impacts by the drop-ball impact test. The purpose of the experiment is to analyse if the electric response of TENG is dependent on the energy of the impact. The results of the experiment are presented and discussed. The main contributions of this work are the preparation of a novel nanogenerator (TENG) based on the triboelectric interaction between polyvinylidene fluoride and polyvinylpyrrolidone sub-micron polymer fibers and the investigation of its potential use as a self-powered impact sensor.

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Haas, A. K., A. Revil, M. Karaoulis, et al. "Electric potential source localization reveals a borehole leak during hydraulic fracturing." GEOPHYSICS 78, no. 2 (2013): D93—D113. http://dx.doi.org/10.1190/geo2012-0388.1.

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A laboratory experiment was performed to see if passively recorded electric signals can be inverted to retrieve the position of fluid leakages along a well during an attempt to hydraulically fracture a porous block in the laboratory. The cubic block was instrumented with 32 nonpolarizing sintered Ag/AgCl electrodes. During the test, several events were detected corresponding to fluid leakoff along the seal of the well. Each event showed a quick burst in the electric field followed by an exponential-type relaxation of the potential distribution over time. The occurrence of these “electric” events was always correlated with a burst in the acoustic emissions and a change in the fluid pressure. These self-potential data were inverted in two steps: (1) using a deterministic least-square algorithm with focusing to retrieve the position of the source current density in the block for a given snapshot in the electric potential distribution and (2) using a genetic algorithm to refine the position of the source current density on a denser grid. The results of the inversion were found to be in excellent agreement with the position of the well where the hydraulic test was performed and with the localization of the acoustic emissions in the vicinity of this well. This experiment indicates that passively recorded electric signals can be used to monitor fluid flow along the well during leakages, and perhaps monitor fluid flow for numerous applications involving hydromechanical disturbances.

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Gonsalves, Tayara Correia, Franks Martins Silva, Ligia Silverio Vieira, Julio Cesar Serafim Casini, and Rubens Nunes de Faria. "Electrochemical Characteristics and Microstructures of Activated Carbon Powder Supercapacitors for Energy Storage." Materials Science Forum 930 (September 2018): 597–602. http://dx.doi.org/10.4028/www.scientific.net/msf.930.597.

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In recent years, extensive investigations have focused on the study and improvement of supercapacitor electrode materials. The electric devices produced with these materials are used to store energy over time periods ranging from seconds to several days. The main factor that determines the energy storage period of a supercapacitor is its self-discharge rate, i.e., the gradual decrease in electric potential that occurs when the supercapacitor terminals are not connected to either a charging circuit or electric load. Self-discharge is attenuated at lower temperatures, resulting in an increased energy storage period. This paper addresses the temperature-dependence of self-discharge via a systematic study of supercapacitors with nominal capacitances of 1.0 and 10.0 F at DC potentials of 5.5 and 2.7 V, respectively. The specific capacitances, internal resistances, and self-discharge characteristics of commercial activated carbon electrode supercapacitors were investigated. Using cyclic voltammetry, the specific capacitances were determined to be 44.4 and 66.7 Fg−1 for distinct carbon electrode supercapacitors. The self-discharge characteristics were investigated at both room temperature and close to the freezing point. The internal resistances of the supercapacitors were calculated using the discharge curves at room temperature. The microstructures of the electrode materials were determined using scanning electron microscopy.

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Matsui, H., P. A. Puhl-Quinn, V. K. Jordanova, Y. Khotyaintsev, P. A. Lindqvist, and R. B. Torbert. "Derivation of inner magnetospheric electric field (UNH-IMEF) model using Cluster data set." Annales Geophysicae 26, no. 9 (2008): 2887–98. http://dx.doi.org/10.5194/angeo-26-2887-2008.

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Abstract. We derive an inner magnetospheric electric field (UNH-IMEF) model at L=2–10 using primarily Cluster electric field data for more than 5 years between February 2001 and October 2006. This electric field data set is divided into several ranges of the interplanetary electric field (IEF) values measured by ACE. As ring current simulations which require electric field as an input parameter are often performed at L=2–6.6, we have included statistical results from ground radars and low altitude satellites inside the perigee of Cluster in our data set (L~4). Electric potential patterns are derived from the average electric fields by solving an inverse problem. The electric potential pattern for small IEF values is probably affected by the ionospheric dynamo. The magnitudes of the electric field increase around the evening local time as IEF increases, presumably due to the sub-auroral polarization stream (SAPS). Another region with enhanced electric fields during large IEF periods is located around 9 MLT at L>8, which is possibly related to solar wind-magnetosphere coupling. Our potential patterns are consistent with those derived from self-consistent simulations. As the potential patterns can be interpolated/extrapolated to any discrete IEF value within measured ranges, we thus derive an empirical electric potential model. The performance of the model is evaluated by comparing the electric field derived from the model with original one measured by Cluster and mapped to the equator. The model is open to the public through our website.

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Bennett, Roger, and Rohini Vijaygopal. "Consumer attitudes towards electric vehicles." European Journal of Marketing 52, no. 3/4 (2018): 499–527. http://dx.doi.org/10.1108/ejm-09-2016-0538.

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Purpose The purpose of this paper is to investigate the effects of gamification on connections between consumers’ self-image congruence in relation to the purchasers of an environmentally friendly product electric vehicles (EVs) and their possession of a stereotype of EV owners as being “unconventional”, and their attitudes towards EVs, having regard to their levels of environmental concern and prior knowledge of EVs. Additionally, the research explored the link between attitudes towards and willingness to purchase EVs. Design/methodology/approach Participants completed a questionnaire and an Implicit Association Test (IAT) both before and after playing a computer game wherein the player assumed the identity of an EV driver. A structural equation model was constructed to predict attitude to EVs. The relationship between attitude and willingness to purchase was examined via a conditional process analysis. Findings The experience of playing the game improved the favourability of the respondents’ stereotype of EV owners by an average of 19 per cent, and their attitude towards EVs by 17 per cent. Self-image congruence in relation to EV ownership increased on the average by 14 per cent and reported EV product knowledge by 8 per cent. However, willingness to purchase an EV was not substantially affected. The link between attitude and willingness to purchase was weak, but was significantly moderated by stereotype favourability and self-image congruence with EV owners. Research limitations/implications As with any IAT study, it was necessary to pre-specify a particular form of stereotype. Future research could employ alternative stereotypes. The investigation took place in a single country and involved a single environmentally friendly product. Practical implications Gamification has much potential for helping manufacturers and government agencies to stimulate the mass market for EVs. To negate unfavourable images of EV owners, marketing communications promoting EVs might usefully employ celebrities, sports personalities and/or leading political figures as exemplars of the types of people who drive electric cars. Originality/value The research is the first to explore the effects of gamification on product user self-image congruence and stereotype formation. It is novel both in its employment of an IAT to measure the consumer stereotype of an environmentally friendly product and in its examination of the moderating influences of stereotype and product user self-image congruence on the attitude-willingness to purchase link.

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Tronolone, James J., Michael Orrill, Wonbin Song, Hyun Soo Kim, Byung Yang Lee, and Saniya LeBlanc. "Electric Field Assisted Self-Assembly of Viruses into Colored Thin Films." Nanomaterials 9, no. 9 (2019): 1310. http://dx.doi.org/10.3390/nano9091310.

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Filamentous viruses called M13 bacteriophages are promising materials for devices with thin film coatings because phages are functionalizable, and they can self-assemble into smectic helicoidal nanofilament structures. However, the existing “pulling” approach to align the nanofilaments is slow and limits potential commercialization of this technology. This study uses an applied electric field to rapidly align the nanostructures in a fixed droplet. The electric field reduces pinning of the three-phase contact line, allowing it to recede at a constant rate. Atomic force microscopy reveals that the resulting aligned structures resemble those produced via the pulling method. The field-assisted alignment results in concentric color bands quantified with image analysis of red, green, and blue line profiles. The alignment technique shown here could reduce self-assembly time from hours to minutes and lend itself to scalable manufacturing techniques such as inkjet printing.

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Zuhdi, Muhammad, Jannatin Ardhuha, Kosim Kosim, Wahyudi Wahyudi, and Muhammad Taufik. "Program Komputer Berbasis Matlab untuk Perhitungan Charge Occurence Probability Data Self Potensial." Kappa Journal 4, no. 2 (2020): 172–77. http://dx.doi.org/10.29408/kpj.v4i2.2677.

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Self Potential arises due to electric charge of minerals in contact with the electrolyte solution around these minerals. Charge Occurrence Probability (COP) is one of the methods of interpretation of potential self data, the measurement of which is carried out using two porouspot electrodes.. This study aims to create a computer-based program Matlab is for calculating COP. The stages of this research are creating program algorithms, making Matlab-based syntax and making the main program for COP calculation. The program that has been created is then tested on synthetic data formed by the convolution of potential fields with random numbers. The study is limited to two-dimensional computation algorithms. Theoretically, the resulting resolution of this algorithm depends on the data density of the self potential. This program is proven to provide a good map for interpretation of potential self data

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ZHANG, LI, and HONG-JING XIE. "ELECTRO-OPTIC EFFECT IN A SEMI-PARABOLIC QUANTUM WELL WITH AN APPLIED ELECTRIC FIELD." Modern Physics Letters B 17, no. 09 (2003): 347–54. http://dx.doi.org/10.1142/s0217984903005366.

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By using the compact density matrix approach, the electro-optic effect (EOE) in a semi-parabolic quantum well (QW) with an applied electric field has been theoretically investigated. Via a variant of displacement harmonic oscillation, the exact electronic states in the semi-parabolic QW with an applied electric field are obtained. Numerical results on typical GaAs material reveal that the electro-optic effect nearly linearly increases with the increasing of magnitude of the electric field, but it monotonously decreases with the increasing of confining potential frequency of the semi-parabolic QW. The EOE in the model investigated is 102 times larger than that in the symmetric parabolic QW under the same electric field and the same frequency of parabolic confining potential, which is due to the self-asymmetry of the system and the electric field effect.

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AKHMETOV, Yermek M., Kambar M. ASSEMOV, and Victor N. SHAYTOROV. "Geophysical survey of earthen dam using the electrical prospecting methods." Contributions to Geophysics and Geodesy 50, no. 2 (2020): 249–59. http://dx.doi.org/10.31577/congeo.2020.50.2.4.

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The hydraulic structures for the land reclamation needs and their operation are the objects of careful attention. The water-bearing earth dams of small height pose an extra danger, where the accident occurs the most often. Such facilities should be constantly monitored to prevent the dangerous incidents. The article discusses an alternative method for studying the filtration properties of earth dams by the electrical parameters – resistivity, induced polarization and self-potential. The relative polarizability was used to exclude the influence of electrical resistivity to the induced polarization data. A study of advanced technology to identify the filter zones was carried out on an earthen dam in the Almaty region, Kazakhstan. The measurement data for three profiles are presented as the sections form in the parameters of resistivity and relative polarizability. Their complex interpretation with the respect of self-potential data, is given as a diagram of probable filtration paths. This is possibly due to the local increased watering in the dam loamy body. Then, the electric and self-potential parameters were evaluated to determine the filtering zones. The study results of above parameters have identified several water-saturated zones in the dam body. This technology could be used to estimate the condition of such objects and their engineering-geological monitoring.

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Schwarz, K., H. Ripplinger, and P. Blaha. "Electric Field Gradient Calculations of Various Borides." Zeitschrift für Naturforschung A 51, no. 5-6 (1996): 527–33. http://dx.doi.org/10.1515/zna-1996-5-627.

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Abstract A first-principles method for the computation of electric field gradients (EFG) is illustrated for various borides. It is based on energy band calculations using the full-potential linearized aug-mented plane wave (LAPW) method within density functional theory. From the self-consistent charge density distribution the EFG is obtained without further approximations by numerically solving Poisson's equation. The dependence of the EFG on structure, chemical composition or substitution is demonstrated for the diborides MB2 (with M = Ti, V, Cr, Zr, Nb, Mo, and Ta), the hexaborides (CaB6, SrB6 and BaB6) and boron carbide which is closely related to α-boron.

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MOREIRA, Cesar Augusto, Lívia Portes Innocente HELENE, Fernanda CAVALLARI, Leonardo Paioli CARRAZZA, and João Carlos DOURADO. "ANALYSIS OF RAINFALL INFLUENCE IN BIOGAS PRODUCTION AND VARIATIONS IN THE SELF-POTENTIAL IN A LANDFILL." Geosciences = Geociências 36, no. 3 (2017): 589–97. http://dx.doi.org/10.5016/geociencias.v36i3.11730.

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Biogas is a chemical compound rich in methane, generated by the degradation of organic matter, flammable power and applicable to energy generation. Landfills are areas with great potential for biogas generation due to the large amount of organic matter contained in solid domestic waste. The sizing and design of projects to capture and generate energy in landfills depend on reliable estimates of future generation of biogas. The currently available models are deficient in many respects due to the exclusion of relevant factors in the biogas generation process. This paper presents the results of natural electric potential through geophysical logging technique, developed alongside gas drains located in areas with residues of different ages of landfill deposition, when accompanied by measures of biogas flow and rainfall, biweekly during 12 months. The key objective was to evaluate the sensitivity of the physical parameter to seasonal variations and its relation to the production of biogas. The results show that the availability of organic matter able to degradation was the main factor responsible for differences in biogas production between the drains examined, although there are variations in periods of drought or rain. The natural electric potential demonstrated proportional variations of biogas flow rates measured in drains with different ages, where the largest biogas flows are associated to more electronegative or more reducing areas

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Zhao, Xuan, Zheng Zhang, Qingliang Liao, et al. "Self-powered user-interactive electronic skin for programmable touch operation platform." Science Advances 6, no. 28 (2020): eaba4294. http://dx.doi.org/10.1126/sciadv.aba4294.

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User-interactive electronic skin is capable of spatially mapping touch via electric readout and providing visual output as a human-readable response. However, the high power consumption, complex structure, and high cost of user-interactive electronic skin are notable obstacles for practical application. Here, we report a self-powered, user-interactive electronic skin (SUE-skin), which is simple in structure and low in cost, based on a proposed triboelectric-optical model. The SUE-skin achieves the conversion of touch stimuli into electrical signal and instantaneous visible light at trigger pressure threshold as low as 20 kPa, without external power supply. By integrating the SUE-skin with a microcontroller, a programmable touch operation platform was built that can recognize more than 156 interaction logics for easy control of consumer electronics. This cost-effective technology has potential relevance to gesture control, augmented reality, and intelligent prosthesis applications.

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Meldra, Delia. "PEMODELAN KONTINU 2-D BERBASIS EFEK ELEKTOKINETIK DENGAN FINITE ELEMENT PENDEKATAN GALERKIN." JURNAL REKAYASA SISTEM INDUSTRI 4, no. 2 (2019): 93. http://dx.doi.org/10.33884/jrsi.v4i2.1277.

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Method refers to a measurement of naturally electric potential on the surface. Self Potential is one of thegeophysical methods that can be used to identify fluid flow in the subsurface. Finite element method hasbeen used to fluid flow velocity modeling, current source, and potential distribution modeling based onelectrokinetic effect in 2-D profile. The sign of potensial respon (negative or positive) is an important factorfor the interpretation of self-potential anomalies. Finite element method is one of the numerical methods forsolve the boundary value problems and the boundary conditions in the form of differential equations in SelfPotentialmodeling

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Thamaraiselvan, Chidambaram, Avner Ronen, Sofia Lerman, Moran Balaish, Yair Ein-Eli, and Carlos G. Dosoretz. "Low voltage electric potential as a driving force to hinder biofouling in self-supporting carbon nanotube membranes." Water Research 129 (February 2018): 143–53. http://dx.doi.org/10.1016/j.watres.2017.11.004.

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Nickschick, Tobias, Christina Flechsig, Cornelia Meinel, Jan Mrlina, and Horst Kämpf. "Architecture and temporal variations of a terrestrial CO2 degassing site using electric resistivity tomography and self-potential." International Journal of Earth Sciences 106, no. 8 (2017): 2915–26. http://dx.doi.org/10.1007/s00531-017-1470-0.

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KURIPLACH, J., and P. NOVÁK. "CALCULATION OF ELECTRIC FIELD GRADIENT AND CRYSTAL FIELD PARAMETERS IN RARE EARTH METALS." International Journal of Modern Physics B 07, no. 01n03 (1993): 609–13. http://dx.doi.org/10.1142/s0217979293001281.

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Electronic structure of hcp rare earth metals Gd, Tb, Dy, Lu and rare-earth-like Y is calculated using the spin-polarized version of the full potential LAPW method. The electric field gradient at the nucleus site is determined from the nonspherical part of the charge density. Crystal field parameters are obtained from the nonspherical components of self-consistent potential. The influence of the state of the 4f-system on the valence and semi-core electrons is investigated.

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Essa, Khalid S., Zein E. Diab, and Mahmoud Elhussein. "Self-potential Data Interpretation for Two Co-axial Structures Utilizing the RMS Parameter." Journal of Environmental and Engineering Geophysics 25, no. 1 (2020): 15–23. http://dx.doi.org/10.2113/jeeg19-017.

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We have developed an algorithm to obtain the model parameters for two co-axial structures from self-potential data. The method uses the first numerical horizontal derivatives calculated from the observed self-potential anomaly employing filters of sequential window lengths (s-values) so as to gauge the model constraints for the shallow and deep structures. In addition, this algorithm uses a standard inversion method for solving a non-linear equation based on the lowest root-mean-square (RMS) error of the estimated model parameters. The body constraints are the depth, polarization angle and electric dipole moment of each structure. Our approach models the self-potential dataset as an aggregation of spheres, horizontal cylinders, and vertical cylinders. These simple bodies are used to approximate, without a priori expectations, the furthermost plausible position and/or area of intersection. In other words, the bodies are used to estimate the true values of the source parameters for the two-co-axial bodies at different s-values. Minimizing the RMS error has the advantage of optimizing all model factors. The proposed technique is tested using a numerical model with and without noise and on self-potential field data acquired at a site in Germany. In all cases, the assessed body parameters are reasonable approximations of the known values.

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Minsley, Burke J., Darrell A. Coles, Yervant Vichabian, and Frank Dale Morgan. "Minimization of self-potential survey mis-ties acquired with multiple reference locations." GEOPHYSICS 73, no. 2 (2008): F71—F81. http://dx.doi.org/10.1190/1.2829390.

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Self-potential (SP) surveys often involve many interconnected lines of data along available roads or trails, with the ultimate goal of producing a unique map of electric potentials at each station relative to a single reference point. Multiple survey lines can be tied together by collecting data along intersecting transects and enforcing Kirchhoff’s voltage law, which requires that the total potential drop around any closed loop equals zero. In practice, however, there is often a nonzero loop-closure error caused by noisy data; traditional SP processing methods redistribute this error evenly over the measurements that form each loop. The task of distributing errors and tying lines together becomes nontrivial when many lines of data form multiple interconnected loops because the loop-closure errors are not independent, and a unique potential field cannot be determined by processing lines sequentially. We present a survey-consistent processing method that produces a unique potential field by minimizing the loop-closure errors over all lines of data simultaneously. When there are no interconnected survey loops, the method is equivalent to traditional processing schemes. The task of computing the potential field is posed as a linear inverse problem, which easily incorporates prior information about measurement errors and model constraints. We investigate the use of both [Formula: see text] and [Formula: see text] measures of data misfit, the latter requiring an iterative-solution method with increased computational cost. The [Formula: see text] method produces more reliable results when outliers are present in the data, and is similar to the [Formula: see text] result when only Gaussian noise is present. Two synthetic examples are used to illustrate this methodology, which is subsequently applied to a field data set collected as part of a geothermal exploration campaign in Nevis, West Indies.

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Стефанович, Л. И. "Влияние дискообразных непроводящих включений на электропроводность материала на постоянном токе". Журнал технической физики 91, № 2 (2021): 207. http://dx.doi.org/10.21883/jtf.2021.02.50353.188-20.

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The influence of non-conductive disk-like inclusions (fractures) on the conductivity of a conducting medium in direct current is considered. To find the additional specific electrical resistance due to cracks, a self-consistent problem for the current density has been solved. In this case, a hydrodynamic analogy was used between the motion of an ideal incompressible fluid during potential flow around solids and electric current flowing around fractures. The functional dependences of the resulting relative additional specific electrical resistance of the material on the fracturing coefficient for thick and thin samples are found. A graphical visualization of these dependences shows that for a thick specimen, for all real values of the coefficient of fracturing, it is linear and is determined by the shape of the fractures. For a thin sample, the dependence of the relative additional the specific electrical resistance of the material on the fracturing coefficient is proportional to the thickness of the sample and is nonlinear. The obtained dependences of the additional electrical resistivity can be used, in particular, as a non-invasive method for determining the fracturing coefficient of rock samples conducting electric current.

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Journal articles on the topic 'Electric self potential'

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