Gotowa bibliografia na temat „Solids - Electron Clouds”
Utwórz poprawne odniesienie w stylach APA, MLA, Chicago, Harvard i wielu innych
Zobacz listy aktualnych artykułów, książek, rozpraw, streszczeń i innych źródeł naukowych na temat „Solids - Electron Clouds”.
Przycisk „Dodaj do bibliografii” jest dostępny obok każdej pracy w bibliografii. Użyj go – a my automatycznie utworzymy odniesienie bibliograficzne do wybranej pracy w stylu cytowania, którego potrzebujesz: APA, MLA, Harvard, Chicago, Vancouver itp.
Możesz również pobrać pełny tekst publikacji naukowej w formacie „.pdf” i przeczytać adnotację do pracy online, jeśli odpowiednie parametry są dostępne w metadanych.
Artykuły w czasopismach na temat "Solids - Electron Clouds"
1
Zhang, Tao. "Influence factors and adjusting method of refractive indices of solid media". Modern Physics Letters B 32, nr 32 (20.11.2018): 1850391. http://dx.doi.org/10.1142/s0217984918503918.
Pełny tekst źródłaStreszczenie:
It is of great significance to explore changing behavior and adjustment method of the refractive index. Expression of the refractive index, which was derived from the electron-cloud conductor model, contains the equivalent volume V of the electron clouds and the molecular density [Formula: see text]. The expression shows that the refractive index increases with V and [Formula: see text]. Based on this expression, main factors influencing the refractive index of solid medium are analyzed and summarized: the Nephelauxetic Effect, number of bonding electrons in the molecule, chemical bond property, number of nonbonding electrons in outermost layer of the molecule, and molecular density of the medium (electromagnetic wave factor is not considered). The relationship between the refractive index and the Nephelauxetic Effect is established. The calculations show that the Nephelauxetic Effect helps to increase the refractive index. Some viewpoints related to the Nephelauxetic Effect are supplemented. Characteristics of the solid medium that has a high refractive index are proposed: (1) Covalent bond component is high, and number of covalent bonds in one molecule is large. (2) Periodic number is as large as possible without increasing the ionic bond component. (3) Molecular density is high. According to these characteristics, method of adjusting the refractive index is discussed, and the results are consistent with the real situations.
2
Kucherov, Olexandr. "Direct Visualization of Si and Ge Atoms by Shifting Electron Picoscopy". Applied Functional Materials 2, nr 4 (30.12.2022): 10–16. http://dx.doi.org/10.35745/afm2022v02.04.0002.
Pełny tekst źródłaStreszczenie:
The picoscopy images of the Si/Ge(100) system were analyzed, and electron cloud densitometry of silicon is presented in this study. The picoscopy is used to distinguish Ge, Si, and other chemical elements because different atoms have different densities of electron clouds. This result is in full accordance with Kucherov's law which states that the current passed through an electron cloud is proportional to the density of the cloud. The picoscopy image has shown Si crystals, Si/Ge solid solution, and their interface as the single crystal without defects. Local deformations in crystals were investigated using methods of direct visualization of individual atoms and measuring the distance of the center of atoms from the node of the crystal lattice. Visual сrystallography becomes a new way to study applied functional materials. This is the first publication on the real structure of a silicon atom.
3
Sotome, M., M. Nakamura, J. Fujioka, M. Ogino, Y. Kaneko, T. Morimoto, Y. Zhang i in. "Spectral dynamics of shift current in ferroelectric semiconductor SbSI". Proceedings of the National Academy of Sciences 116, nr 6 (22.01.2019): 1929–33. http://dx.doi.org/10.1073/pnas.1802427116.
Pełny tekst źródłaStreszczenie:
Photoexcitation in solids brings about transitions of electrons/holes between different electronic bands. If the solid lacks an inversion symmetry, these electronic transitions support spontaneous photocurrent due to the geometric phase of the constituting electronic bands: the Berry connection. This photocurrent, termed shift current, is expected to emerge on the timescale of primary photoexcitation process. We observe ultrafast evolution of the shift current in a prototypical ferroelectric semiconductor antimony sulfur iodide (SbSI) by detecting emitted terahertz electromagnetic waves. By sweeping the excitation photon energy across the bandgap, ultrafast electron dynamics as a source of terahertz emission abruptly changes its nature, reflecting a contribution of Berry connection on interband optical transition. The shift excitation carries a net charge flow and is followed by a swing over of the electron cloud on a subpicosecond timescale. Understanding these substantive characters of the shift current with the help of first-principles calculation will pave the way for its application to ultrafast sensors and solar cells.
4
Sauvaud, J. A., P. Koperski, T. Beutier, H. Barthe, C. Aoustin, J. J. Thocaven, J. Rouzaud, E. Penou, O. Vaisberg i N. Borodkova. "The INTERBALL-Tail ELECTRON experiment: initial results on the low-latitude boundary layer of the dawn magnetosphere". Annales Geophysicae 15, nr 5 (31.05.1997): 587–95. http://dx.doi.org/10.1007/s00585-997-0587-z.
Pełny tekst źródłaStreszczenie:
Abstract. The Toulouse electron spectrometer flown on the Russian project INTERBALL-Tail performs electron measurements from 10 to 26 000 eV over a 4<pi> solid angle in a satellite rotation period. The INTERBALL-Tail probe was launched on 3 August 1995 together with a subsatellite into a 65° inclination orbit with an apogee of about 30 RE. The INTERBALL mission also includes a polar spacecraft launched in August 1996 for correlated studies of the outer magnetosphere and of the auroral regions. We present new observations concerning the low-latitude boundary layers (LLBL) of the magnetosphere obtained near the dawn magnetic meridian. LLBL are encountered at the interface between two plasma regimes, the magnetosheath and the dayside extension of the plasma sheet. Unexpectedly, the radial extent of the region where LLBL electrons can be sporadically detected as plasma clouds can reach up to 5 RE inside the magnetopause. The LLBL core electrons have an average energy of the order of 100 eV and are systematically field-aligned and counterstreaming. As a trend, the temperature of the LLBL electrons increases with decreasing distance to Earth. Along the satellite orbit, the apparent time of occurrence of LLBL electrons can vary from about 5 to 20 min from one pass to another. An initial first comparison between electron- and magnetic-field measurements indicates that the LLBL clouds coincide with a strong increase in the magnetic field (by up to a factor of 2). The resulting strong magnetic field gradient can explain why the plasma-sheet electron flux in the keV range is strongly depressed in LLBL occurrence regions (up to a factor of \\sim10). We also show that LLBL electron encounters are related to field-aligned current structures and that wide LLBL correspond to northward interplanetary magnetic field. Evidence for LLBL/plasma-sheet electron leakage into the magnetosheath during southward IMF is also presented.
5
Kouchi, Akira, Masashi Tsuge, Tetsuya Hama, Hiromasa Niinomi, Naoki Nakatani, Takashi Shimonishi, Yasuhiro Oba i in. "Formation of chiral CO polyhedral crystals on icy interstellar grains". Monthly Notices of the Royal Astronomical Society 505, nr 1 (27.04.2021): 1530–42. http://dx.doi.org/10.1093/mnras/stab1173.
Pełny tekst źródłaStreszczenie:
ABSTRACT The crystallinity and morphology of solid carbon monoxide (CO) on icy interstellar grains were examined by observing the deposition, crystallization, and UV and electrons irradiation of solid CO using transmission electron microscopy. Herein, we found that solid CO deposited in molecular clouds was crystalline, and that even if amorphous CO was deposited, amorphous CO crystallized within 103 yr at 10 K. Conversely, crystalline CO was not amorphized by UV rays or electron beam at 10 K. These results indicated the occurrence of chiral crystalline CO instead of amorphous CO in space. Furthermore, the large surface diffusion coefficients of CO on eamorphous H2O and crystalline CO at 10 K facilitated the morphological equilibration of crystalline CO. Bad wetting of crystalline CO with amorphous H2O proved that the morphology of the ice grains was not spherical with an onion-like structure, as hitherto assumed, but rather it was a polyhedral crystalline CO attached to amorphous H2O. This has important implications for phenomena associated with the collision and subsequent sticking between ice grains, surface chemical reactions, non-thermal desorption of molecules and the origin of homochirality in interstellar biomolecules.
6
Celebonovic, Vladan, i W. Dappen. "The plasma-solid transition: some implications in astrophysics". Serbian Astronomical Journal, nr 165 (2002): 23–26. http://dx.doi.org/10.2298/saj0265023c.
Pełny tekst źródłaStreszczenie:
Using a criterion proposed by Salpeter and standard solid-state physics, we have determined the Debye temperature of a solid in equilibrium with the electron gas surrounding it. The results obtained can have astrophysical applications in the determination of parameters of interstellar and interplanetary clouds.
7
Slaughter, J. M., W. Weber, Gernot Güntherodt i Charles M. Falco. "Quantitative Auger and XPS Analysis of Thin Films". MRS Bulletin 17, nr 12 (grudzień 1992): 39–45. http://dx.doi.org/10.1557/s0883769400046947.
Pełny tekst źródłaStreszczenie:
In 1925, P. Auger first observed the so-called Auger electrons in a Wilson cloud chamber. He explained this occurrence as being due to a radiationless transition in atoms excited by a primary x-ray photon source. In 1953, Lander first pointed out that Auger electrons arising from solid samples can be detected in the energy distribution curve of secondary electrons from surfaces subjected to electron bombardment. Moreover, low-energy Auger electrons (∼1 keV kinetic energy) can escape from only the first several atomic layers of a surface since they are strongly absorbed by even a monolayer of atoms. Thus Auger electron spectroscopy (AES) possesses high surface sensitivity. This is one characteristic that makes AES very useful for the study of thin films. For such applications, an important development in AES occurred when Harris showed that the sensitivity of the detection of Auger electrons can be improved by differentiating the electron energy distribution curve with respect to the energy. Furthermore, Weber and Johnson demonstrated that, provided the Auger line profile does not change, the peak-to-peak height in the differentiated energy distribution curves is proportional to the Auger current in the peak. Therefore, in addition to its surface sensitivity, AES also can be used for quantitative studies of thin films.Like AES, x-ray photoelectron spectroscopy (XPS) is a surface-sensitive technique that uses the energy distribution of electrons ejected from a thin film for quantitative analysis. However, in many ways the information provided by AES and XPS is complementary.
8
Liu, Fei, Shan Cong i Long Hao. "First principle study of occupancy, bonding characteristics and alloying effect of Zr, Nb, V in bulk γ-Fe(C)". E3S Web of Conferences 213 (2020): 01019. http://dx.doi.org/10.1051/e3sconf/202021301019.
Pełny tekst źródłaStreszczenie:
The total energy, binding characteristics, density of states, charge distribution and differential charge density of γ-Fe(C)-M crystal cells formed by solid solution of Zr, Nb and V in γ-Fe(C) were calculated by using the first-principles method. Thus, the mechanism of Zr, Nb, and V with γ-Fe(C) was investigated in this paper. The results show that Zr, Nb and V all preferentially replaced the Fe atoms which are at the top angle in γ-Fe(C). Crystal cell reaches its highest stability after V solid solution. Nb reaches after it, and Zr is relatively weak. In the γ-Fe(C)-Zr cell, Fe-Zr covalent bond and Zr-C ionic bond are the main chemical bonds. In the γ-Fe(C)-Nb and γ-Fe(C)-V cells, Fe-Nb and Fe-V covalent bonds are the main chemical bonds with a number of Nb-C and V-C ionic bonds. After solid solution, the electron cloud density around C atom changed little, while Fe atom changed obviously. The orbital electrons around Fe atoms in γFe(C)-V has maximal distribution, which means that the electrons delocalized most and most of the electrons are bonding. It is the main factor for the increase in the binding energy of crystal cell. The effects of Zr, Nb, V solution on austenitic stability are investigated by studying the influence of alloy element on γFe(C) electronic structure.
9
Zhang, Tao. "Relationship between band gap and equivalent volume of electron cloud". Modern Physics Letters B 34, nr 35 (25.08.2020): 2050400. http://dx.doi.org/10.1142/s021798492050400x.
Pełny tekst źródłaStreszczenie:
The characteristic parameter [Formula: see text] related to bandgap [Formula: see text] is proposed ([Formula: see text] is the equivalent volume of the outermost electron cloud of molecule). [Formula: see text] values of dozens of solid media are calculated. The results show that [Formula: see text] decreases as [Formula: see text] increases. Furthermore, change behavior of [Formula: see text] with composition is studied by using [Formula: see text], and the composition characteristics of high-[Formula: see text] solid media are summarized. According to this result, [Formula: see text] can be regulated to a certain extent by adjusting the composition. Importantly, connection among refractive index [Formula: see text], [Formula: see text] and [Formula: see text] is revealed: [Formula: see text] has both a major contribution to [Formula: see text] and a decisive effect on [Formula: see text]. These results help to promote the development of new semiconductor materials.
10
Yuan, Xiaoping, Chengxia Shi i Zhihong Wang. "The Optimization of Hospital Financial Management Based on Cloud Technology and Wireless Network Technology in the Context of Artificial Intelligence". Wireless Communications and Mobile Computing 2022 (18.05.2022): 1–11. http://dx.doi.org/10.1155/2022/9998311.
Pełny tekst źródłaStreszczenie:
In the reign of Internet technology, cloud technology has emerged as one of the powerful tools in computing with many advantages in the bag. Cloud technology is defined as online access to all types of computing applications. The applications range from access to data, servers, software, databases to storage and retrieval of data. The data can be accessed from anywhere, anytime. The user does not need to own the hardware in this case. Clouds have multiple data centers located at various places. On-demand data service is the best part of cloud technology. This technology is made use in many industries. In this research, we will study how cloud technology and wireless networking technology are applied to optimize hospital financial management. The healthcare industry faces various challenges in financial management such as budgeting, growth planning, and cost-effectiveness. Considering this scenario, it is evident that there is a solid need to optimize its financial management. The cloud computing technology driven by artificial intelligence (AI) is deployed in carrying out repetitive tasks and automation, resulting in increased productivity. In this research, the proposed system uses wireless networking systems and cloud technology to optimize hospital financial management. The model works with the implementation of a hybrid of fuzzy neural networks. The proposed model is analyzed with the existing fuzzy logic and neural network models, and it is found that the proposed model has obtained an accuracy of 97.56% with minimum resources for successful financial management at hospitals.
Części książek na temat "Solids - Electron Clouds"
1
Schroeder, Daniel V. "Quantum Statistics". W An Introduction to Thermal Physics, 257–326. Oxford University Press, 2021. http://dx.doi.org/10.1093/oso/9780192895547.003.0007.
Pełny tekst źródłaStreszczenie:
This chapter begins by extending the Boltzmann distribution to the case of a system that exchanges particles with its environment. This idea finds direct applications ranging from hemoglobin adsorption to ionization of atoms in stars. But the main applications are to dense “gases” in which the quantum behavior of identical particles comes into play. Examples include conduction electrons in metals and semiconductors; white dwarf and neutron stars; photon gases and thermal radiation from incandescent objects; neutrino and electron-positron production in the early universe; quasiparticles associated with vibrations and magnetic excitations in solids; and Bose-Einstein condensation of ultracold clouds of atoms.
2
Kenyon, Ian R. "Electrons in solids". W Quantum 20/20, 75–94. Oxford University Press, 2019. http://dx.doi.org/10.1093/oso/9780198808350.003.0005.
Pełny tekst źródłaStreszczenie:
Electron energy bands in solids are introduced. Free electron theory for metals is presented: the Fermi gas, Fermi energy and temperature. Electrical and thermal conductivity are interpreted, including the Wiedermann–Franz law. The Hall effect and information it brings about charge carriers is discussed. Plasma oscillations of conduction electrons and the optical properties of metals are examined. Formation of quasi-particles of an electron and its screening cloud are discussed. Electron-electron and electron-phonon scattering and how they affect the mean free path are treated. Then the analysis of crystalline materials using electron Bloch waves is presented. Tight and weak binding cases are examined. Electron band structure is explained including Brillouin zones, electron kinematics and effective mass. Fermi surfaces in crystals are treated. The ARPES technique for exploring dispersion relations is explained.
3
Khodabacchus, Muhammad Yaasir. "Managing Risk in the Cloud for Digital Preservation". W Advances in Library and Information Science, 209–30. IGI Global, 2017. http://dx.doi.org/10.4018/978-1-5225-1653-8.ch011.
Pełny tekst źródłaStreszczenie:
Digital preservation is the consistent archiving of electronic assets for entry and re-use, regardless of the system and computer software options. The introduction of cloud technologies provides a stylish alternative, although preservation systems possess a solid focus on grids. Electronic preservation has turned cloud computing into the primary demand. Cloud services' use continues to rise, however many do not know how several and which cloud services is or not authorized and how they are really in use across their businesses. This kind of incomplete image of the Cloud Services in an organization prevent its capacity to satisfactorily address the hazards related to cloud solutions, including information protection, consumer privacy, dependability of essential business processes, and compliance hazards. Tycoons' involvement is necessary to shift businesses toward better cloud support knowledge as well as a trusted, structured, and foreseeable method of cloud use.
4
Schippert, E., C. Möhner, B. Pannwitt i Horst Chmiel. "Waste air cleaning using activated carbon fibre cloths regenerable by direct electric heating". W Characterization of Porous Solids VI, Proceedings of the 6th International Symposium on the Characterization of Porous Solids (COPS-VI), 507–13. Elsevier, 2002. http://dx.doi.org/10.1016/s0167-2991(02)80174-4.
Pełny tekst źródła
5
Sun, Ying, Zhipeng Su, Qiong Wu, Feiou Yu, Ying Zhao i Enzhen Hou. "Clock Synchronization Methods of Electric Meters Based on Wireless Communication". W Advances in Transdisciplinary Engineering. IOS Press, 2022. http://dx.doi.org/10.3233/atde220015.
Pełny tekst źródłaStreszczenie:
Aiming at the inaccurate clock calibration of electric meters and the shortcomings of traditional clock synchronization methods, this article briefly summarizes the reasons of inaccurate meter clocks, and proposes a method of electric meter clock calibration based on wireless communication, which solves the problem of meter clock synchronization accuracy. It is verified by field test. The test results show that the error of electric meters clock after clock calibration can be controlled at the second level. And the data error of collected import active electrical energy is smaller, which meets the requirements of real-time analysis of electricity spot trading and other businesses, providing more accurate data to ensure the results reliability.
Streszczenia konferencji na temat "Solids - Electron Clouds"
1
Soare, G. "A Physical Model of the Molecular-Quantum Natural Convection Heat Transfer Mechanism". W ASME 2003 Heat Transfer Summer Conference. ASMEDC, 2003. http://dx.doi.org/10.1115/ht2003-47401.
Pełny tekst źródłaStreszczenie:
In this work a physical model of the natural convection heat transfer mechanism, molecular-quantum in nature, is proposed. On the surface of the solid there are a lot of chemical defects (atoms of different chemical elements) and geometrical ones (steps, kinks, terraces, dislocations) at microscopic and nanoscopic scale. All these defects make the surface of the wall to be not an equipotential surface. On the other hand, the existence of a gradient of temperature in a metal wall, which is involved in a heat transfer process, generates a gradient of conduction electrons. On the cool face of the wall there are more electrons as a result of Pe´ltier-Thomson effect. Because of surface’s defects the electrons are not uniformly distributed, on a high defect there are more electrons than on a depth defect and the electrical field is more intense on the high defect. The molecules of the fluid are adsorbed on the surface, and become polar molecules, as a result of the polarization by influence. The absorbed molecules form a multilayer in which take place more elementary processes, molecular-quantum in nature. These elementary processes are: the overlap between the electronic orbital of the solid and fluid, electron clouds perturbation, solid-fluid electron exchange by quantum tunneling effect, the motion under action of the Helmann-Feynman force between adsorbed molecules and a high defect of the wall, the absorption of the phonons from the surface’s atoms and rejection of the molecules from the surface. In this way natural convection is generated. The proposed model needs directly experimental confirmation.
2
Portella-Oberli, Marcia T., Catherine Jeannin i Majed Chergui. "“Bubble” dynamics following Rydberg state excitation in rare gas matrices". W International Conference on Ultrafast Phenomena. Washington, D.C.: Optica Publishing Group, 1996. http://dx.doi.org/10.1364/up.1996.pdp.3.
Pełny tekst źródłaStreszczenie:
The dynamics of Rydberg states in condensed matter is still a field to be unravelled. The radius of low-n Rydberg states is comparable to the nearest neighbour distance in rare gas solids. Consequently, following photoexcitation of such states in a solid matrix, there will be a short-range repulsive interaction between the Rydberg electron and the electronic cloud of the neighbouring matrix atoms. This repulsion leads to a local expansion around the electronically excited center and results in the formation of a "microscopic cavity", or "bubble", surrounding the molecule as the solvent atoms are pushed asunder to a new equilibrium position /1-4/. In conventional spectroscopy, this is inferred from the large blue gas-to-matrix shifts of absorption bands and the strong absorption-emission Stokes shifts.
3
Smolin, Jill. "The making of nebula clouds for the motion picture “sphere”, with volumetric rendering and the f-Rep of solids". W ACM SIGGRAPH 98 Electronic art and animation catalog. New York, New York, USA: ACM Press, 1998. http://dx.doi.org/10.1145/281388.281918.
Pełny tekst źródła
4
Choudhury, P. Roy. "Some Aspects of Particle Agglomeration in Simulated Slurry Fuels". W ASME 1997 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 1997. http://dx.doi.org/10.1115/imece1997-0880.
Pełny tekst źródłaStreszczenie:
Abstract A series of experiments and analyses with JP-10 slurries, prepared with inert particles ranging in size from 0.3 μm to 2 μm, have been performed to study the influence of particle size, mass loading and droplet diameter on particle agglomeration in a slurry fuel. Particle mass loadings of 20% and 50% in droplets ranging in size from 100 μm to 3000 μm were studied analytically. Inert SiC and Al2O3 particles were chosen to avoid the complexities associated with reacting solids. Similarly, slurries were prepared without any chemical additives which could decompose. The choice of non-stabilized slurry with inert particles was made in order to isolate the problem under study, and not to cloud the issue of particle agglomeration due to burning particles and secondary reactions involving chemical stabilizers. Scanning Electron Microscopic (SEM) studies of the residues from burning and also evaporating droplets suggest that instead of using the usual very small particles (1 μm or smaller), intermediate size particles (∼ 3 μm) should be used in preparing the slurries. Intermediate size particles are affected neither by any interacting forces nor by chemical cementation caused by fuel decomposition at the particle surface heated by flame radiation. Therefore, the intermediate size particles are expected to minimize particle agglomeration. Analysis corroborates the fact that fuel decomposition is negligible at the surface of small particles. Also the solid mass loading between 20% and 50% seems to have a very small effect on fuel decomposition at the particle surface. Because of increased mass and heat transfer rates in a flow field, analysis predicts a lower degree of fuel decomposition when droplets are exposed to flow.
5
Daxiang, Yang Zhang, Li Debajit Basak i Kong-Pang Pun. "Reduction of clock jitter effect in 1-bit CT delta-sigma modulators by correlated clocks". W 2017 International Conference on Electron Devices and Solid-State Circuits (EDSSC). IEEE, 2017. http://dx.doi.org/10.1109/edssc.2017.8126421.
Pełny tekst źródła
6
Dede, Ercan M., Shailesh N. Joshi i Feng Zhou. "Topology Optimization, Additive Layer Manufacturing, and Experimental Testing of an Air-Cooled Heat Sink". W ASME 2015 International Technical Conference and Exhibition on Packaging and Integration of Electronic and Photonic Microsystems collocated with the ASME 2015 13th International Conference on Nanochannels, Microchannels, and Minichannels. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/ipack2015-48027.
Pełny tekst źródłaStreszczenie:
Topology optimization of an air-cooled heat sink considering heat conduction plus side-surface convection is presented. The optimization formulation is explained along with multiple design examples. A post-processing procedure is described to synthesize water-tight solid model computer-aided design (CAD) geometry from 3-D point-cloud data extracted from the optimization result. Using this process, a heat sink is optimized for confined jet impingement air cooling. A prototype structure is fabricated out of AlSi12 using additive layer manufacturing (ALM). The heat transfer and fluid flow performance of the optimized heat sink is experimentally evaluated, and the results are compared with benchmark plate and pin-fin heat sink geometries that are conventionally machined out of aluminum and copper. In two separate test cases, the experimental results indicate that the optimized ALM heat sink design has a higher coefficient of performance relative to the benchmark heat sink designs.
7
Simpson, Greer, Tom Littleford i Anthony Battistel. "High-Resolution Acoustic Imaging for Submillimetric Casing Thickness Quantification and Advanced Effective-Area-Based Burst Pressure Analyses". W SPE Annual Technical Conference and Exhibition. SPE, 2022. http://dx.doi.org/10.2118/210010-ms.
Pełny tekst źródłaStreszczenie:
Abstract High-resolution acoustic imaging has provided a novel means of quantifying casing thickness; the technology assesses both inner and outer diameter wall loss for downhole casing integrity applications. The technology deploys high-density solid-state arrays with up to 512 transducers to achieve sub-degree azimuthal resolution and submillimetric axial resolution with casing thickness measurements down to 0.08-in minimum thickness. This paper provides background on the technological advancement, details of laboratory validation results, exploration of burst pressure calculation methodologies, and a field case study based on the novel technology. Data gathered by the high-density, solid-state transducer array uses acoustic signals to measure both casing thickness and radial measurements in a single pass. The resulting 3D point cloud of data is analyzed with image-processing-based machine learning algorithms. Validation data was gathered from multiple machined and field samples. Machined defect dimensions were varied to test the detection, sizing, and accuracy capabilities of the platform. A field-based case study is presented to provide a comparison between high-resolution acoustic imaging data and computed tomography (CT) scan data. Finally, examples of RSTRENG burst pressure analyses are presented to showcase the advantages and sensitivities of using higher-resolution datasets and higher-accuracy burst pressure methodologies. The high-resolution acoustic imaging platform was found to offer fundamental improvements over legacy magnetic flux leakage (MFL) and single-element ultrasound-based tools. The acoustic technology relies on direct measurement principles; the results are not inferred through calibration. The time-of-flight-based approach permits a single casing string comprised of different diameters, wall thicknesses, and materials to be inspected from a single logging run. The technology is pipe material agnostic and directly measures the casing thickness of ferrous and non-ferrous metals. The electronic platform permits the capture and storage of submillimetric axial resolution which captures penetration profiles of entire defects. The high-resolution and spatially registered datasets have been leveraged to conduct effective area, RSTRENG, and modified B31G burst pressure calculations with greatly improved defect identification, penetration quantification, interaction rule application, and shape characterization. The advancements presented in this paper are highly pertinent to gas storage and carbon sequestration operators who seek integrity management advancements. The potential to extend well life, optimize workover schedules, and better manage gas storage pressure ratings are real-world benefits of the presented technology.