Journal articles: 'Internal diffusion'

1

John I. Koivula, John I. "Internal diffusion." Journal of Gemmology 20, no. 7 (1987): 474–77. http://dx.doi.org/10.15506/jog.1987.20.7.474.

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2

Lawler, Gregory F., Maury Bramson, and David Griffeath. "Internal Diffusion Limited Aggregation." Annals of Probability 20, no. 4 (October 1992): 2117–40. http://dx.doi.org/10.1214/aop/1176989542.

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3

Sanderson, Brian G., and Akira Okubo. "Diffusion by internal waves." Journal of Geophysical Research 93, no. C4 (1988): 3570. http://dx.doi.org/10.1029/jc093ic04p03570.

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4

Young, David J. "Diffusion in Internal Oxidation Reactions." Defect and Diffusion Forum 323-325 (April 2012): 283–88. http://dx.doi.org/10.4028/www.scientific.net/ddf.323-325.283.

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When an alloy component is selectively oxidised but cannot reach the surface quickly enough to form a scale, then internal oxidation results. In this process, a gas phase oxidant dissolves in an alloy and diffuses inwards, reacting with a dilute solute metal to precipitate metal oxide or carbide, etc. Penetration kinetics are parabolic, the rate being controlled by oxidant diffusion and the concentration of reacting metal. Rates are predicted from classical oxidation theory on the basis that the reaction product is exceedingly stable, no solute metal remains in the reacted alloy, and oxidant diffusion is via a solvent metal matrix. This paper is concerned with situations where these approximations fail: the development of low stability precipitates and the growth of elongated precipitates which allow interfacial diffusion of the oxidant. Effects on the rates of internal oxidation are discussed.

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Weissman, M. B. "Internal diffusion noise of fractals." Physical Review B 36, no. 10 (October 1, 1987): 5754–55. http://dx.doi.org/10.1103/physrevb.36.5754.

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6

Ye, Min. "UTILITY AND CONDITIONS OF DIFFUSION BY DIASPORAS: EXAMINING FOREIGN DIRECT INVESTMENT LIBERALIZATION IN CHINA AND INDIA." Journal of East Asian Studies 16, no. 2 (July 2016): 261–80. http://dx.doi.org/10.1017/jea.2016.3.

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AbstractDiffusion studies have rightly emphasized external ideas and resources that propel liberalization in the developing world. There remain two gaps: first, the literature has not covered the types of diffusers and the ways diasporas may shape liberalization in their homelands; second, it pays little attention to internal diffusion after national adoption within a country. This article explores the utility and conditions of diffusion by diasporas and examines the roles of diasporas and internal diffusion in China and India's FDI liberalization. In both countries, diasporas were main diffusers that led national adoption of liberalism at home. In China, however, entrepreneurial diasporas' networks with local governments helped expansive internal diffusion. India's professional diasporas did not strongly engage local governments or domestic companies. National adoption in India was followed by reversal and partial internal diffusions. India's software services provide a similar diffusion by diasporas to that in China.

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Schatzman, Evry. "Diffusion process produced by random internal waves." Journal of Fluid Mechanics 322 (September 10, 1996): 355–82. http://dx.doi.org/10.1017/s0022112096002820.

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The aim of the paper is to present a new transport process which is likely to have great importance for understanding the internal constitution of the stars.In order to set the problem in context, we first give a short presentation of the physical properties of the Sun and stars, described usually under the names Standard Solar Model or Standard Stellar Models (SSM). Next we show that an important shortcoming of SSM is that they do not explain the age dependence of the lithium deficiency of stars of known age: stars of galactic clusters and the Sun. It was suggested a long time ago that the presence of a macroscopic diffusion process in the radiative zone should be assumed, below the surface convective zone of solar-like stars. It is then possible for the lithium present in the convective zone to be carried to the thermonuclear burning level below the convective zone. The first assumption was that differential rotation generates turbulence and therefore that a turbulent diffusion process takes place. However, this model predicts a lithium abundance which is strongly rotation dependent, contrary to the observations. Furthermore, as the diffusion coefficient is large all over the radiative zone, it prevents the possibility of gravitational separation by diffusion and consequently leads to the impossibility of explaining the difference in helium abundance between the surface and the centre of the Sun. The consequence is obviously that we need to take into account another physical process.Stars having a mass M < 1.3M[odot ] have a convective zone which begins close to the stellar surface and extends down to a depth which is an appreciable fraction of the stellar radius. In the convective zone, strong stochastic motions carry, at least partially, heat transfer. These motions do not vanish at the lower boundary and generate internal waves into the radiative zone. These random internal waves are at the origin of a diffusion process which can be considered as responsible for the diffusive transport of lithium down to the lithium burning level. This is certainly not the only physical process responsible for lithium deficiency in main sequence stars, but its properties open the way to a completely consistent analysis of lithium deficiency.The model of generation of gravity waves is based on a model of heat transport in the convective zone by diving plumes. The horizontal component of the turbulent motion at the boundary of the convective zone is assumed to generate the horizontal motion of internal waves. The result is a large horizontal component of the diffusion coefficient, which produces in a short time an horizontally uniform chemical composition. It is known that gravity waves, in the absence of any dissipative process, cannot generate vertical mixing. Therefore, the vertical component of the diffusion coefficient is entirely dependent on radiative damping. It decreases quickly in the radiative zone, but is large enough to be responsible for lithium burning.Owing to the radial dependence of velocity amplitude, the diffusion coefficient increases when approaching the stellar centre. However, very close to the centre, nonlinear dissipative and radiative damping of internal waves become large and the diffusion coefficient vanishes at the very centre.

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KIM, MOON-SOO, and HO KIM. "INNOVATION DIFFUSION OF TELECOMMUNICATIONS: GENERAL PATTERNS, DIFFUSION CLUSTERS AND DIFFERENCES BY TECHNOLOGICAL ATTRIBUTE." International Journal of Innovation Management 08, no. 02 (June 2004): 223–41. http://dx.doi.org/10.1142/s136391960400099x.

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We investigated the patterns of the technological diffusions of 17 Korean information and telecommunications (IT) innovations by applying various diffusion models, where the Bass model was chosen the most robust one. Although the internal influence dominates diffusion process for most innovations, the external influence was found to be meaningful to Korean IT diffusion compared with US's. Based on estimated parameters — penetration rate, innovation and imitation coefficients, we conducted cluster analysis, which resulted in four clusters and two isolated innovations. Differences of diffusion patterns between circuit-based and packet-based technology were examined by the external and internal influence as well as the critical mass point. Based on these findings we proposed the several practical implications for ISPs providing packet-based services, Telecommunications carriers with circuit and packet-based services, as well as policy makers.

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9

Meakin, Paul, and Tamás Vicsek. "Internal structure of diffusion-limited aggregates." Physical Review A 32, no. 1 (July 1, 1985): 685–88. http://dx.doi.org/10.1103/physreva.32.685.

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10

Petit, Andrew S., and Anne B. McCoy. "Diffusion Monte Carlo in Internal Coordinates." Journal of Physical Chemistry A 117, no. 32 (March 13, 2013): 7009–18. http://dx.doi.org/10.1021/jp312710u.

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Dewett, Todd, Nathan C. Whittier, and Scott David Williams. "Internal diffusion: the conceptualizing innovation implementation." Competitiveness Review 17, no. 1/2 (March 2007): 8–25. http://dx.doi.org/10.1108/10595420710816579.

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12

Smedskjaer, Morten M., Yuanzheng Yue, Joachim Deubener, Haraldur P. Gunnlaugsson, and Steen Mørup. "Modifying glass surfaces via internal diffusion." Journal of Non-Crystalline Solids 356, no. 6-8 (March 2010): 290–98. http://dx.doi.org/10.1016/j.jnoncrysol.2009.12.004.

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13

Kulys, J. "Modeling Trienzyme Biosensor at Internal Diffusion Limitation." Nonlinear Analysis: Modelling and Control 9, no. 2 (April 25, 2004): 139–44. http://dx.doi.org/10.15388/na.2004.9.2.15162.

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A model of biosensor containing three immobilized enzymes utilizing consecutive substrate conversion in the chain was developed. The modeling was performed at an internal diffusion limitation and a steadystate condition. The calculations showed that significant response of biosensors was produced if diffusion modules were larger than 1 for all enzyme reactions. Due to diffusion limitation the apparent stability of biosensor response increased many times in comparison to stability of the most labile enzyme of the chain.

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14

Christensen-Dalsgaard, J. "Internal Structure." Highlights of Astronomy 10 (1995): 323–26. http://dx.doi.org/10.1017/s1539299600011369.

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In this section I concentrate on the spherically symmetric aspects of solar structure, corresponding to “classical” stellar evolution models. Such models are characterized by a number of simplifying assumptions, as well as by the physical properties of matter in the star, conveniently labeled “micro-physics”. The latter include descriptions of the equation of state, the opacity and the nuclear reaction rates; in addition, molecular diffusion, included in several recent calculations, should be considered as part of the micro-physics. The assumptions in the standard calculations, simplifying what might be called the macro-physics, include the neglect of effects of rotation and magnetic fields (implicit in the assumption of spherical symmetry), as well as the assumption that material mixing occurs only in convectively unstable regions, or possibly as a result of molecular diffusion and settling; also, convective energy transport is treated crudely through some form of mixing-length approximation and the contribution to hydrostatic balance from the turbulent motion in the convection zone, usually called turbulent pressure, is ignored.

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15

Ruthven, Douglas M., and Adam Vidoni. "ZLC diffusion measurements: Combined effect of surface resistance and internal diffusion." Chemical Engineering Science 71 (March 2012): 1–4. http://dx.doi.org/10.1016/j.ces.2011.11.040.

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16

Dayyala, Niharika, Syed Kashif Raza Zaidi, and Kallol Bagchi. "Diffusion of IFRS using innovation diffusion models." International Journal of Accounting & Information Management 28, no. 4 (June 1, 2020): 685–701. http://dx.doi.org/10.1108/ijaim-01-2020-0002.

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Purpose This study aims to examine the diffusion pattern of International Financial Reporting Standards (IFRS) into the countries and identifies the channels of diffusion. Design/methodology/approach Data includes 98 countries that made a public commitment to IFRS adoption from 2000 to 2016. Adoptee countries are categorized based on Rogers’ adopter categorizations to understand country characteristics. Innovation diffusion models such as internal influence, external influence and bass diffusion that explain diffusion patterns are applied to the cumulative adoption of IFRS. Coefficients of internal and external diffusion are obtained using the models to explain the mode of diffusion pattern of IFRS. Further tests are done to identify the best model that explains IFRS diffusion. Findings Findings show that IFRS diffusion is a result of external influence through vertical communication from a centralized body (IASB) and internal influence due to imitation and interpersonal communication between countries. Imitation effect among the countries has a stronger effect on the IFRS adoption compared to the communication obtained from IASB. Practical implications Findings obtained can help standards-setting bodies, organizations and countries to understand the potential future of adopters and non-adopters. It facilitates the standard-setting bodies to manage IFRS diffusion by implementing measures to spread the word on the benefits of IFRS. Originality/value The study generates value by modeling a successive increase in the number of IFRS adoptee countries using empirical methods and identifies the reasons for the diffusion life cycle of IFRS.

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17

Chen, Yong Tai, Ming Xie, You Cai Yang, Ji Ming Zhang, Man Men Liu, Sai Bei Wang, Song Wang, and Jie Qiong Hu. "Study on the Behavior of Internal Oxidation of Ag-Cu-Zn Alloy." Applied Mechanics and Materials 395-396 (September 2013): 196–200. http://dx.doi.org/10.4028/www.scientific.net/amm.395-396.196.

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the behavior of internal oxidation of Ag-Cu-Zn alloy was studied at various internal oxidation temperatures for different internal oxidation time. The experimental results show that the short path diffusion, such as boundary diffusion and surface diffusion, is the main diffusion channel of oxygen in initial stage of oxidation, oxidation rate is fast, while the internal oxidation exponent n=1. Then the oxygen diffusion translated from short path diffusion into long path diffusion with the extending of internal oxidation time, and the oxidation rate was slowed down, while the internal oxidation exponent n=1.67. The action size is increased with the temperature increase. The diffusion activation energy of oxygen in initial stage of oxidation is lower than that in middle and late stage.

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18

Watari, Fumio, Shigeaki Abe, Kazuchika Tamura, Motohiro Uo, Atsuro Yokoyama, and Yasunori Totsuka. "Internal Diffusion of Micro/Nanoparticles Inside Body." Key Engineering Materials 361-363 (November 2007): 95–98. http://dx.doi.org/10.4028/www.scientific.net/kem.361-363.95.

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Both biochemical cell functional test and animal implantation test were done to investigate the reaction to fine particles. Particles cause nonspecifically phagocytosis to cells and inflammation to tissue for the size below 10m. With the size below 50nm particles may invade into the internal body through the respiratory or digestive system and diffuse inside body. Ti mapping by XSAM after the compulsory exposure test to the respiratory system showed the internal diffusion of 30nm TiO2 particles. They diffused with time course to lung, liver and spleen after injection from caudal vein. Nanoparticles might be the objects whose existence has not been assumed by the biophylactic system.

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19

Walterscheid, R. L., and W. K. Hocking. "Stokes Diffusion by Atmospheric Internal Gravity Waves." Journal of the Atmospheric Sciences 48, no. 20 (October 1991): 2213–30. http://dx.doi.org/10.1175/1520-0469(1991)048<2213:sdbaig>2.0.co;2.

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20

Lawler, Gregory F. "Subdiffusive Fluctuations for Internal Diffusion Limited Aggregation." Annals of Probability 23, no. 1 (January 1995): 71–86. http://dx.doi.org/10.1214/aop/1176988377.

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21

Wang, S. P., and M. Schwartz. "Reorientational diffusion and internal rotation in trichloroethane." Journal of Physical Chemistry 94, no. 6 (March 1990): 2702–5. http://dx.doi.org/10.1021/j100369a085.

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22

Aarão Reis, F. D. A. "Diffusion on fractals with interacting internal boundaries." Journal of Chemical Physics 111, no. 1 (July 1999): 310–16. http://dx.doi.org/10.1063/1.479272.

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23

Bal, Guillaume, and François Monard. "Inverse diffusion problems with redundant internal information." Inverse Problems and Imaging 6, no. 2 (May 2012): 289–313. http://dx.doi.org/10.3934/ipi.2012.6.289.

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Podgaetskii, E. M. "Diffusion in solid plate taking into account internal adsorption of diffusing component." Protection of Metals and Physical Chemistry of Surfaces 47, no. 3 (May 2011): 286–90. http://dx.doi.org/10.1134/s2070205111030117.

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Dayananda, Mysore A. "Selected Analyses and Observations in Multicomponent Diffusion." Defect and Diffusion Forum 297-301 (April 2010): 1451–60. http://dx.doi.org/10.4028/www.scientific.net/ddf.297-301.1451.

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Selected isothermal diffusion studies in ternary and quaternary systems are reviewed in order to present analytical and experimental approaches adopted for the determination of interdiffusion fluxes of components, interdiffusion coefficients, diffusional interactions among components, and internal consistency in the experimental data. Several interesting phenomena and observations including uphill diffusion, zero-flux planes and flux reversals, and double serpentine diffusion paths are illustrated with selected single phase Cu-Ni-Zn, Fe-Ni-Al and Cu-Ni-Zn-Mn diffusion couples. The main challenges involved in the experimental determination of interdiffusion data from multicomponent diffusion couples and in the application of such data are also addressed.

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Daley, Dorothy M., and James C. Garand. "Horizontal Diffusion, Vertical Diffusion, and Internal Pressure in State Environmental Policymaking, 1989-1998." American Politics Research 33, no. 5 (September 2005): 615–44. http://dx.doi.org/10.1177/1532673x04273416.

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27

OHSUGI, Y., and MASATAKA KINJO. "ANALYSIS OF MEMBRANE-BINDING PROTEIN MOBILITY IN LIVING CELLS USING TOTAL INTERNAL REFLECTION FLUORESCENCE CORRELATION SPECTROSCOPY." Biophysical Reviews and Letters 01, no. 03 (July 2006): 293–99. http://dx.doi.org/10.1142/s1793048006000227.

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Total internal reflection fluorescence correlation spectroscopy (TIR-FCS) is an appropriate method for measuring diffusion constants and the number of fluorescent molecules very close to the coverglass surface. Recently, we have reported the application of TIR-FCS to cell biology, measuring membrane-binding farnesylated green fluorescent proteins (EGFP-F) in living cells. In this research, we measured the signal transduction molecule, protein kinase C (PKC), fused with EGFP in living HeLa cells by using TIR-FCS. We observed two different diffusional mobilities of PKCβII-EGFP, three-dimensional faster diffusion near the plasma membrane and slower lateral diffusion on the plasma membrane after adinosine tri phosphate (ATP) activation. These results indicate that it is possible to use TIR-FCS in the study of molecular dynamics and interactions of signal transduction proteins on the plasma membrane of the living cell.

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Aniţa, Sebastian, and Bedreddine Ainseba. "Internal eradicability for an epidemiological model with diffusion." Mathematical Biosciences and Engineering 2, no. 3 (2005): 437–43. http://dx.doi.org/10.3934/mbe.2005.2.437.

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Rabkin, Eugen, V. Semenov, W. Gust, and Lasar S. Shvindlerman. "Diffusion-Induced Instabilities at Internal Interfaces in Solids." Defect and Diffusion Forum 143-147 (January 1997): 1373–84. http://dx.doi.org/10.4028/www.scientific.net/ddf.143-147.1373.

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30

Kul’kov, V. G. "Diffusion model of internal friction in nanocrystalline materials." Technical Physics 52, no. 3 (March 2007): 333–38. http://dx.doi.org/10.1134/s1063784207030085.

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31

Koc, Zafer, Gurcan Erbay, and Elif Karadeli. "Internal comparison standard for abdominal diffusion-weighted imaging." Acta Radiologica 58, no. 9 (December 12, 2016): 1029–36. http://dx.doi.org/10.1177/0284185116681040.

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Background Standards for abdominal diffusion-weighted imaging (DWI), apparent diffusion coefficient (ADC) measurements, and analysis are required for reproducibility. Purpose To identify optimal internal comparison standards for DWI to normalize the measured ADC for increased accuracy of differentiating malignant and benign abdominal lesions. Material and Methods We retrospectively studied 97 lesions (89 patients; age, 57 ± 13 years) with histopathologically confirmed abdominal disease. Seven normal body parts/contents (normal parenchyma, spleen, kidney, gallbladder bile, paraspinal muscle, spinal cord, and cerebrospinal fluid [CSF]) were assessed as internal references for possible use as comparison standards. Three observers performed ADC measurements. Statistical analyses included interclass correlation coefficients (ICCs), Mann–Whitney and Kruskal–Wallis tests, and coefficient of variation (CV). ROC analyses were performed to assess diagnostic accuracy of lesion ADC and normalized ADC for differentiating lesions. Pathology results were the reference standard. Results Mean and normalized ADCs were significantly lower for malignant lesions than for benign lesions ( P < 0.001). ICC was excellent for all internal references. Gallbladder had the lowest CV. Receiver operating characteristic (ROC) analyses showed that normalized ADCs obtained using normal parenchyma were better than lesion ADCs for differentiating malignant and benign abdominal lesions (area under the curve [AUC], 0.808 and 0.756, respectively). The normalized ADCs obtained using CSF shows higher accuracy than lesion ADCs (0.80 and 0.76, respectively) for differentiating between malignant and benign abdominal lesions. Conclusion The normal parenchyma from a lesion-detected organ can be used as an internal comparison standard for DWI. CSF can be used as a generalizable in plane reference standard.

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Lee, Sangyun, Ji-Hyun Kim, and Sangyoub Lee. "Internal Diffusion-Controlled Enzyme Reaction: The Acetylcholinesterase Kinetics." Journal of Chemical Theory and Computation 8, no. 2 (January 31, 2012): 715–23. http://dx.doi.org/10.1021/ct2006727.

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van Zee, Gerard, Marc Bisschops, and Jan de Graauw. "Internal Sherwood numbers for diffusion in sorption operations." Chemical Engineering and Processing: Process Intensification 36, no. 3 (June 1997): 201–8. http://dx.doi.org/10.1016/s0255-2701(97)00001-9.

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Furman, Gregory B., and Shaul D. Goren. "NQR Spin Diffusion in an Inhomogeneous Internal Field." Hyperfine Interactions 159, no. 1-4 (October 11, 2005): 109–19. http://dx.doi.org/10.1007/s10751-005-9088-1.

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35

Huss, Wilfried. "Internal Diffusion-Limited Aggregation on non-amenable graphs." Electronic Communications in Probability 13 (2008): 272–79. http://dx.doi.org/10.1214/ecp.v13-1374.

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Cox, Arthur N., Joyce A. Guzik, and Russell B. Kidman. "Oscillations of solar models with internal element diffusion." Astrophysical Journal 342 (July 1989): 1187. http://dx.doi.org/10.1086/167675.

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Benjamini, Itai, Hugo Duminil-Copin, Gady Kozma, and Cyrille Lucas. "Internal diffusion-limited aggregation with uniform starting points." Annales de l'Institut Henri Poincaré, Probabilités et Statistiques 56, no. 1 (February 2020): 391–404. http://dx.doi.org/10.1214/19-aihp965.

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Dong, Wang Yuan. "Internal Stabilization of a Mutualistic Reaction Diffusion System." Acta Mathematica Sinica, English Series 23, no. 2 (December 11, 2006): 373–84. http://dx.doi.org/10.1007/s10114-005-0911-z.

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Navalho, J. E. P., J. M. C. Pereira, and J. C. F. Pereira. "Multi-Scale Modeling of Internal Mass Diffusion Limitations in CO Oxidation Catalysts." Defect and Diffusion Forum 364 (June 2015): 92–103. http://dx.doi.org/10.4028/www.scientific.net/ddf.364.92.

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This work applies a 3D multi-scale bottom-up approach for modeling the processes of diffusion and reaction-diffusion in porous catalyst layers. The performance of the random pore model to predict effective transport coefficients are compared with the results of the multi-scale diffusion model. The results of the 3D multi-scale diffusion model are employed in a 1D pseudo-homogeneous reaction-diffusion model with a relative good agreement with the 3D multi-scale reaction-diffusion model. Furthermore, the former multi-scale model was coupled to a full-scale reactor model with good results and high advantages in terms of computational time savings.

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Sinder, Misha. "Properties of Species Profiles during Oxygen Chemical Diffusion in Oxides." Defect and Diffusion Forum 383 (February 2018): 153–58. http://dx.doi.org/10.4028/www.scientific.net/ddf.383.153.

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This is a theoretical study of species profiles during the oxygen chemical diffusion in an acceptor doped oxide crystal driven by large changes in the ambient oxygen partial pressure. The oxide crystal containing three species: mobile oxygen vacancy, mobile electron, immobile dopant ion, is considered. Our analysis is based on the expression of the chemical diffusion coefficient obtained in the framework of the concept of conservative ensembles (Maier J., 1993). It is shown that the dependence of chemical diffusion coefficient on ambient oxygen partial pressure in double-logarithmic coordinates is divided into distinct intervals. For each pressure interval the chemical diffusion equation is reduced to the diffusion equation with a diffusion coefficient which exhibits a power dependence on concentration. First, we analyzed the chemical diffusion under pressure inside each interval. As a result two singularities on the species diffusion profiles can be found: an internal reaction diffusion front, and an ambipolar diffusion front. This ambipolar diffusion front is characterized by a step of the electron concentration, moving inside a specimen. Afterwards, we consider a crystal in which the range of partial pressure spans all considered pressure intervals.

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Hua, Yu-Chao, and Bing-Yang Cao. "Transient in-plane thermal transport in nanofilms with internal heating." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 472, no. 2186 (February 2016): 20150811. http://dx.doi.org/10.1098/rspa.2015.0811.

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Wide applications of nanofilms in electronics necessitate an in-depth understanding of nanoscale thermal transport, which significantly deviates from Fourier's law. Great efforts have focused on the effective thermal conductivity under temperature difference, while it is still ambiguous whether the diffusion equation with an effective thermal conductivity can accurately characterize the nanoscale thermal transport with internal heating. In this work, transient in-plane thermal transport in nanofilms with internal heating is studied via Monte Carlo (MC) simulations in comparison to the heat diffusion model and mechanism analyses using Fourier transform. Phonon-boundary scattering leads to larger temperature rise and slower thermal response rate when compared with the heat diffusion model based on Fourier's law. The MC simulations are also compared with the diffusion model with effective thermal conductivity. In the first case of continuous internal heating, the diffusion model with effective thermal conductivity under-predicts the temperature rise by the MC simulations at the initial heating stage, while the deviation between them gradually decreases and vanishes with time. By contrast, for the one-pulse internal heating case, the diffusion model with effective thermal conductivity under-predicts both the peak temperature rise and the cooling rate, so the deviation can always exist.

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Krupp, Ulrich, Katrin Jahns, Kamil Balinski, and Jürgen Wübbelmann. "Numerical Analysis of Diffusion-Controlled Internal Corrosion by the Cellular Automata Approach." Defect and Diffusion Forum 383 (February 2018): 51–58. http://dx.doi.org/10.4028/www.scientific.net/ddf.383.51.

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The cellular automata method offers a promising approach to describe diffusion and diffusion-controlled precipitation processes at high temperatures. During high temperature exposure, technical components like gas-turbine blades, furnaces, or exhaust systems, are operating in corrosive atmospheres. The resulting material-degradation processes are diffusion‐controlled, and corrosive species penetrate into the material leading to the formation of embrittling precipitates. Cellular automata (CA) represent distributed dynamical systems whose structure is particularly well suited to determine the temporal evolution of the system. In this study, it is shown that the model is able to consider diffusion, nucleation and growth aspects, interdiffusion between scales, and high diffusivity paths like grain boundaries. This has been demonstrated by applying CA to (i) nitrogen diffusion, (ii) internal intergranular oxidation of nickel-based alloy, and (iii) interdiffusion of a binary diffusion couple.

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Khina, Boris B. "Extended 'Five-Stream' Model for Diffusion of Implanted Dopants in Silicon during Ultra-Shallow Junction Formation in VLSI Circuits." Defect and Diffusion Forum 277 (April 2008): 107–12. http://dx.doi.org/10.4028/www.scientific.net/ddf.277.107.

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Ion implantation of different dopants (donors and acceptors) into crystalline silicon with subsequent thermal annealing is used for the formation of ultra-shallow p-n junctions in VLSI technology. The experimentally observed phenomenon of transient enhanced diffusion (TED) during annealing hinders further downscaling of advanced VLSI circuits. However, modern mathematical models of dopant diffusion, which are based on the so-called “five-stream” approach, and software packages such as SUPREM4 encounter difficulties in describing TED. In this work, an extended five-stream model for diffusion in silicon is developed, which takes into account all the possible charge states of point defects (vacancies and silicon self-interstitials) and diffusing pairs “dopant atom–vacancy” and “dopant atom–silicon self-interstitial”. The model includes diffusion and drift of differently charged point defects and pairs in the internal electric field and the kinetics of interaction between unlike species. The expressions for diffusion fluxes and sink/source terms that appear in the non-linear, non-steady-state reaction-diffusion equations are derived for both donor and acceptor dopants accounting for multiple charge states of the diffusing species.

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MOSONYI, L., R. HELD, and CH KOCSÁN. "On the Diffusion of Penicillin." Acta Medica Scandinavica 132, no. 5 (April 24, 2009): 487–94. http://dx.doi.org/10.1111/j.0954-6820.1949.tb18191.x.

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Young, David J. "Predicting Internal Oxidation: Building on the Wagner Model." Materials Science Forum 696 (September 2011): 1–11. http://dx.doi.org/10.4028/www.scientific.net/msf.696.1.

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Wagner’s 1959 diffusion model of the internal oxidation process provided a method of predicting the rate at which a binary alloy was penetrated by dissolved oxygen as it precipitated the more reactive (but dilute) alloy component. Parabolic kinetics were predicted to depend on oxygen permeability in the unreacted alloy solvent and also, in cases where the reactive component was sufficiently mobile, the diffusion coefficient of the latter. The model has proven very successful, but is restricted to single oxidant-binary alloy systems, in which the precipitated oxide has extremely low solubility. This paper reviews recent results on a number of internal precipitation processes which cannot be described with the Wagner theory. These include formation of low stability carbides and nitrades; internal precipitation driven by multiple oxidants; the templating effects of prior precipitates on subsequently formed corrosion products; cellular precipitation morphologies; internal interface diffusion effects; volume changes in the reaction zone and the effects upon them of simultaneous external scaling.

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Zhao, Zhi Huan, Zhi Bin Zhao, Ming Ming Jiang, Chuan Zhong Chen, Wei Hai Song, Li Zhang, Li Li Liu, and Hui Jun Yu. "The Distribution Trend of Boron Atoms in Semiconductor Silicon under High Temperature." Key Engineering Materials 871 (January 2021): 243–47. http://dx.doi.org/10.4028/www.scientific.net/kem.871.243.

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The ProENGINEER software is used to build a geometric model for the whole process cavity and internal structure and conduct the internal dynamic simulation of cavity with different diffusion temperatures of 1,000°C, 1,050°C, 1,100°C and 1,150°C, and different diffusion time of 5 min, 10 min, 15 min and 20 min. Analyze the process control indexes by combining with specific thermal diffusion test, and study the relationship between hydrodynamic parameters and diffusion uniformity, Comprehensively investigate the effects of the diffusion temperature and diffusion time on doping, achieving the requirements of impurity distribution in materials.

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Sakamoto, R., H. Yamada, M. Kobayashi, J. Miyazawa, S. Ohdachi, T. Morisaki, S. Masuzaki, et al. "Advanced Operational Regime with Internal Diffusion Barrier on LHD." Fusion Science and Technology 58, no. 1 (August 2010): 53–60. http://dx.doi.org/10.13182/fst10-a10793.

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Gondim, R. R., E. N. Macedo, and R. M. Cotta. "Hybrid solution for transient internal convection with axial diffusion." International Journal of Numerical Methods for Heat & Fluid Flow 17, no. 4 (May 22, 2007): 405–17. http://dx.doi.org/10.1108/09615530710739176.

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Blumen, Alexander. "Anomalous diffusion of particles with internal degrees of freedom." Philosophical Magazine B 81, no. 9 (September 2001): 1021–31. http://dx.doi.org/10.1080/13642810108205788.

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Merlet, Céline, Paul A. Madden, and Mathieu Salanne. "Internal mobilities and diffusion in an ionic liquid mixture." Physical Chemistry Chemical Physics 12, no. 42 (2010): 14109. http://dx.doi.org/10.1039/c0cp01412e.

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Journal articles on the topic 'Internal diffusion'

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