Journal articles: 'Oxygen diffusivity'

1

Potuček, F., and J. Stejskal. "Oxygen diffusivity in Ellis liquids." Chemical Engineering Science 42, no. 11 (1987): 2793–95. http://dx.doi.org/10.1016/0009-2509(87)87034-3.

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2

Börgers, Jacqueline M., and Roger A. De Souza. "The surprisingly high activation barrier for oxygen-vacancy migration in oxygen-excess manganite perovskites." Physical Chemistry Chemical Physics 22, no. 25 (2020): 14329–39. http://dx.doi.org/10.1039/d0cp01281e.

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3

Hashiguchi, Minako, Isao Sakaguchi, Reona Miyazaki, Kazunori Takada, and Naoki Ohashi. "Cobalt Doping as the Controlling Factor of Oxygen Diffusivity in ZnO by More than Four Orders of Magnitude." Defect and Diffusion Forum 363 (May 2015): 85–90. http://dx.doi.org/10.4028/www.scientific.net/ddf.363.85.

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Oxygen diffusivity in ZnO ceramics doped with cobalt was investigated using an isotope tracer method. The oxygen isotope (18O) was introduced by 18O/16O exchange annealing in an 18O2 atmosphere, and the depth profile of the 18O concentration was analyzed by secondary ion mass spectrometry. The results show that oxygen diffusivity in ZnO steeply increases with increasing Co concentration. In fact, the bulk oxygen diffusivity in 15 mol% Co-doped ZnO was four orders of magnitude greater than that of nominally non-doped ZnO. Oxygen diffusivity at grain boundaries was also enhanced by Co-doping.

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4

Chiu, Z. C., M. Y. Chen, D. J. Lee, S. T. L. Tay, J. H. Tay, and K. Y. Show. "Diffusivity of oxygen in aerobic granules." Biotechnology and Bioengineering 94, no. 3 (June 20, 2006): 505–13. http://dx.doi.org/10.1002/bit.20862.

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5

Zhao, Wei, Ying Zhang, Yang Liu, Mingqian Tan, Weiting Yu, Hongguo Xie, Ying Ma, et al. "Oxygen diffusivity in alginate/chitosan microcapsules." Journal of Chemical Technology & Biotechnology 88, no. 3 (June 6, 2012): 449–55. http://dx.doi.org/10.1002/jctb.3845.

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6

Han, R., X. Jin, and C. J. Glover. "Oxygen Diffusivity in Asphalts and Mastics." Petroleum Science and Technology 31, no. 15 (August 3, 2013): 1563–73. http://dx.doi.org/10.1080/10916466.2011.559506.

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7

Valle-Guadarrama, Salvador, Teodoro Espinosa-Solares, Crescenciano Saucedo-Veloz, and Cecilia B. Peña-Valdivia. "Oxygen Diffusivity in Avocado Fruit Tissue." Biosystems Engineering 92, no. 2 (October 2005): 197–206. http://dx.doi.org/10.1016/j.biosystemseng.2005.06.001.

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8

Kobayashi, Kazusuke, and Keizoh Shuttoh. "Oxygen diffusivity of various cementitious materials." Cement and Concrete Research 21, no. 2-3 (March 1991): 273–84. http://dx.doi.org/10.1016/0008-8846(91)90009-7.

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9

XIAO, BOQI, QIWEN HUANG, BOMING YU, GONGBO LONG, and HANXIN CHEN. "A FRACTAL MODEL FOR PREDICTING OXYGEN EFFECTIVE DIFFUSIVITY OF POROUS MEDIA WITH ROUGH SURFACES UNDER DRY AND WET CONDITIONS." Fractals 29, no. 03 (March 24, 2021): 2150076. http://dx.doi.org/10.1142/s0218348x21500766.

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Oxygen diffusion in porous media (ODPM) with rough surfaces (RS) under dry and wet conditions is of great interest. In this work, a novel fractal model for the oxygen effective diffusivity of porous media with RS under dry and wet conditions is proposed. The proposed fractal model is expressed in terms of relative roughness, the water saturation, fractal dimension for tortuosity of tortuous capillaries, fractal dimension for pores, and porosity. It is observed that the normalized oxygen diffusivity decreases with increasing relative roughness and fractal dimension for capillary tortuosity. It is found that the normalized oxygen diffusivity increases with porosity and fractal dimension for pore area. Besides, it is seen that that the normalized oxygen diffusivity under wet condition decreases with increasing water saturation. The determined normalized oxygen diffusivity is in good agreement with experimental data and existing models reported in the literature. With the proposed analytical fractal model, the physical mechanisms of oxygen diffusion through porous media with RS under dry and wet conditions are better elucidated. Every parameter in the proposed fractal model has clear physical meaning, with no empirical constant.

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10

Clair, Todd P. St, Jill M. Restad, and S. Ted Oyama. "Oxygen diffusivity in MoO3 as determined by a temperature programmed method." Journal of Materials Research 13, no. 6 (June 1998): 1430–33. http://dx.doi.org/10.1557/jmr.1998.0204.

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A temperature programmed method for determining diffusivities has been previously applied to oxygen diffusivity in V2O5. In this communication we extend the method to the case of oxygen diffusivity in MoO3. The reduction of MoO3 to MoO2 using NH3 is utilized to obtain experimental parameters such as the temperature of reduction and the activation energy for oxygen diffusion. These parameters are in turn used to solve Fick's equation for the oxygen diffusivity D0. The utility of this temperature programmed method for obtaining diffusivities has now been clearly established by extension to MoO3.

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11

Kumari, Neetu, Uzma Anjum, M. Ali Haider, and Suddhastawa Basu. "Oxygen Anion Diffusion in Doped Ceria MxCe1-xO2-0.5x (M=Gd, Sm and Pr): A Molecular Dynamics Simulation Study." MRS Advances 4, no. 13 (2019): 783–92. http://dx.doi.org/10.1557/adv.2019.165.

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ABSTRACTMolecular dynamics simulations were utilized to determine the oxygen anion diffusivity in pure ceria (CeO2) and doped ceria MxCe1-xO2-0.5x(M=Gd, Sm and Pr) with varying level of dopant concentration from 5-30% (x = 0.05-0.3). Doping with Gd showed an improvement in oxygen anion diffusivity value by two order of magnitude (D = 4.67x10-8cm2/s at 1173 K) as compared to the undoped ceria (D = 1.33x10-10cm2/s at 1173 K). 10% of doping level was estimated as the optimum concentration of all the dopants at which all of the doped ceria materials showed maximum diffusivity of oxygen anion. Among the three dopants studied, Pr was observed to show maximum diffusivity of oxygen anion in the temperature range of 773-1173 K of simulations.

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12

Nazarpour, S., C. López-Gándara, C. Zamani, F. M. Ramos, and Albert Cirera. "Modification of the oxygen diffusivity in limiting current oxygen sensors." Sensors and Actuators B: Chemical 155, no. 2 (July 2011): 489–99. http://dx.doi.org/10.1016/j.snb.2010.12.052.

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13

Dediu, V., and F. C. Matacotta. "Concentration dependence of oxygen diffusivity inGdBa2Cu3O6+yfilms." Physical Review B 57, no. 13 (April 1, 1998): 7514–17. http://dx.doi.org/10.1103/physrevb.57.7514.

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14

Ma, B., U. Balachandran, J. P. Hodges, J. D. Jorgensen, D. J. Miller, and J. W. Richardson. "Synthesis, conductivity and oxygen diffusivity of Sr2Fe3Ox." Materials Letters 35, no. 5-6 (June 1998): 303–8. http://dx.doi.org/10.1016/s0167-577x(97)00270-x.

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15

LaGraff, John R., and David A. Payne. "Concentration-dependent oxygen diffusivity in YBa2Cu3O6+x." Physica C: Superconductivity 212, no. 3-4 (July 1993): 470–77. http://dx.doi.org/10.1016/0921-4534(93)90616-x.

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16

LaGraff, John R., and David A. Payne. "Concentration-dependent oxygen diffusivity in YBa2Cu3O6+x." Physica C: Superconductivity 212, no. 3-4 (July 1993): 478–86. http://dx.doi.org/10.1016/0921-4534(93)90617-y.

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17

LaGraff, John R., and David A. Payne. "Concentration-dependent oxygen diffusivity in YBa2Cu3O6+x." Physica C: Superconductivity 212, no. 3-4 (July 1993): 487–96. http://dx.doi.org/10.1016/0921-4534(93)90618-z.

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18

Potůček, F., and J. Stejskal. "Diffusivity of oxygen in non-Newtonian liquids." Chemical Engineering Science 41, no. 12 (1986): 3223–26. http://dx.doi.org/10.1016/0009-2509(86)85061-8.

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19

Jürgens, Klaus D., Simon Papadopoulos, Thomas Peters, and Gerolf Gros. "Myoglobin: Just an Oxygen Store or Also an Oxygen Transporter?" Physiology 15, no. 5 (October 2000): 269–74. http://dx.doi.org/10.1152/physiologyonline.2000.15.5.269.

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Besides acting as an oxygen store during times of reduced blood oxygen supply, myoglobin can also facilitate intracellular oxygen transport by diffusion of oxymyoglobin along a Po2 gradient. We reassess the importance of myoglobin-facilitated oxygen diffusion by applying new findings on the intracellular diffusivity of myoglobin in a model calculation.

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20

Ishii, Daiki, Toshimasa Suzuki, Hiroshi Kishi, Isao Sakaguchi, Naoki Ohashi, and Hajime Haneda. "Oxygen Diffusion in SrTiO₃ Thin Films - An Attempt to Measure Oxygen Diffusivity at Relatively Low Temperature." Key Engineering Materials 566 (July 2013): 258–61. http://dx.doi.org/10.4028/www.scientific.net/kem.566.258.

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Oxygen diffusivity in strontium titanate films with intentional non-stoichiometry, Sr1+xTi1+yOδwith (1+x)/(1+y) = 0.71.5, was studied to reveal degradation behavior of Sr1+xTi1+yOδfilms. In order to utilize isotope tracer diffusion measurement, so-called gas/solid exchange method using18O2gas, at relatively low temperature, very thin YSZ layer deposited on top of Sr1+xTi1+yOδfilm was used as catalyst for enhanced18O[gas]/16O[solid] exchange at lower temperature. As a result, very high oxygen diffusivity at 673 K in Sr1+xTi1+yOδfilms with (1+x)/(1+y)>>1 was observed.

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21

Zhou, Qin, and Paul L. Bishop. "Determination of oxygen profiles and diffusivity in encapsulated biomass k-carrageenan gel beads." Water Science and Technology 36, no. 1 (July 1, 1997): 271–77. http://dx.doi.org/10.2166/wst.1997.0064.

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Biofiltration is a popular method for removing volatile organic compounds (VOCs). One promising medium for biofilters is biomass encapsulated gel beads. Like any other biodegradation system, oxygen concentration is an important factor affecting microbial activities in gel beads and thus the VOC removal efficiency. This paper summarizes the studies on oxygen distribution and diffusivity in k-carrageenan gel beads using oxygen microelectrodes to measure oxygen profiles. By using a reaction-diffusion model and the concentration measurements obtained, a homogeneous diffusivity constant and an oxygen consumption rate constant in k-carrageenan gel beads were estimated. The estimated oxygen diffusivity in the gel bead is 46.3% of the value in water when the bead is immersed in water and 53.9% that of water when the bead is in air with a thin liquid film surrounding it. To provide more information for the design and operation of biofilters using biomass-loaded gel beads, we also investigated and report on effects of biomass immobilization time, TCE influent concentration and TCE gas flow rate on oxygen concentrations in the gel bead.

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22

Song, Tangqiumei, Oscar Morales-Collazo, and Joan F. Brennecke. "Solubility and Diffusivity of Oxygen in Ionic Liquids." Journal of Chemical & Engineering Data 64, no. 11 (October 10, 2019): 4956–67. http://dx.doi.org/10.1021/acs.jced.9b00750.

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23

Xie, X. M., T. G. Chen, and J. Huang. "Diffusivity of oxygen in the orthorhombic YBa2Cu3Oy phase." Physica Status Solidi (a) 110, no. 2 (December 16, 1988): 415–19. http://dx.doi.org/10.1002/pssa.2211100212.

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24

Sun, Yan, Shintaro Furusaki, Aizo Yamauchi, and Kunihiro Ichimura. "Diffusivity of oxygen into carriers entrapping whole cells." Biotechnology and Bioengineering 34, no. 1 (June 5, 1989): 55–58. http://dx.doi.org/10.1002/bit.260340107.

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25

Kurosawa, Hiroshi, Masatoshi Matsumura, and Hideo Tanaka. "Oxygen diffusivity in gel beads containing viable cells." Biotechnology and Bioengineering 34, no. 7 (October 5, 1989): 926–32. http://dx.doi.org/10.1002/bit.260340707.

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26

UTAKA, Yoshio, Yutaka TASAKI, Shixue WANG, Toru ISHIJI, and Shoichi UCHIKOSHI. "Method for Measuring Oxygen Diffusivity of Microporous Media." Transactions of the Japan Society of Mechanical Engineers Series B 74, no. 739 (2008): 655–61. http://dx.doi.org/10.1299/kikaib.74.655.

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27

Gegner, J., G. Hörz, and R. Kirchheim. "Diffusivity and solubility of oxygen in solid palladium." Journal of Materials Science 44, no. 9 (May 2009): 2198–205. http://dx.doi.org/10.1007/s10853-008-2923-4.

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28

Linek, V., and J. Sinkule. "Measurement of oxygen diffusivity in non-Newtonian liquids." Chemical Engineering Science 46, no. 5-6 (1991): 1527. http://dx.doi.org/10.1016/0009-2509(91)85079-d.

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29

Utaka, Yoshio, Yutaka Tasaki, Shixue Wang, Toru Ishiji, and Shoich Uchikoshi. "Method of measuring oxygen diffusivity in microporous media." International Journal of Heat and Mass Transfer 52, no. 15-16 (July 2009): 3685–92. http://dx.doi.org/10.1016/j.ijheatmasstransfer.2009.02.032.

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30

Tseng, M. D., H. Indrawirawan, and O. N. Carlson. "Effect of vanadium on oxygen diffusivity in niobium." Journal of the Less Common Metals 136, no. 1 (December 1987): 31–39. http://dx.doi.org/10.1016/0022-5088(87)90006-3.

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31

Jiang, Z., and R. A. Brown. "Atomistic Calculation of Oxygen Diffusivity in Crystalline Silicon." Physical Review Letters 74, no. 11 (March 13, 1995): 2046–49. http://dx.doi.org/10.1103/physrevlett.74.2046.

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32

Fu, Y. C., T. C. Zhang, and P. L. Bishop. "Determination of effective oxygen diffusivity in biofilms grown in a completely mixed biodrum reactor." Water Science and Technology 29, no. 10-11 (October 1, 1994): 455–62. http://dx.doi.org/10.2166/wst.1994.0792.

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Direct measurement of unsteady-state variation of oxygen concentrations inside deactivated biofilm at intervals of 100 μm was conducted with oxygen microelectrodes. The diffusivity of each layer was estimated using an explicit finite-difference method. The results show that the distribution of the biofilm effective oxygen diffusivity varies from 25% Dw at the substratum of the biofilm to 90% Dw at the surface of the biofilm. This information provides experimental evidence necessary for biofilm modelling that could not be approached in the past, and will create a new dimension for evaluation of biofilm processes.

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33

Kissinger, G., J. Dabrowski, Andreas Sattler, Timo Müller, and Wilfried von Ammon. "Two Paths of Oxide Precipitate Nucleation in Silicon." Solid State Phenomena 131-133 (October 2007): 293–302. http://dx.doi.org/10.4028/www.scientific.net/ssp.131-133.293.

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The coherent agglomeration of interstitial oxygen into single-plane and double-plane plates can explain the two peaks in the M-shaped nucleation curves in Czochralski silicon. The density of nucleation sites for the double-plane plates corresponds to the VO2 concentration. Ab initio calculations have shown that the agglomeration of oxygen atoms in single-plane and doubleplane plates is energetically favorable. These plates are under compressive strain. VO2 agglomeration plays only a minor role for modeling the M-shaped nucleation curves because of prior homogenization treatments. It is of much higher impact if as-grown wafers are subjected to nucleation anneals because of the higher vacancy concentration which was frozen in during crystal cooling. This results in higher nucleation rates at higher temperatures. Because the oxygen diffusivity below 700 °C is important for the nucleation rate and many controversial results about the diffusivity in this temperature range were published, we have analyzed the data from literature. We have demonstrated that the effective diffusivity of oxygen at temperatures below 700 °C which corresponds to the quasi equilibrium dimer concentration is very similar to the extrapolation from oxygen diffusivity at high temperature. The high effective diffusivities from out-diffusion and precipitation experiments, and the somewhat lower effective diffusivities from dislocation locking experiments are the result of an ongoing formation of fast diffusing dimers because the equilibrium is disturbed as the result of the strongly increasing difference in the diffusion length between interstitial oxygen and the fast diffusing dimer with decreasing temperature.

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34

Ritzmann, Andrew M., Michele Pavone, Ana B. Muñoz-García, John A. Keith, and Emily A. Carter. "Ab initio DFT+U analysis of oxygen transport in LaCoO3: the effect of Co3+ magnetic states." J. Mater. Chem. A 2, no. 21 (2014): 8060–74. http://dx.doi.org/10.1039/c4ta00801d.

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35

Fielitz, P., Günter Borchardt, S. Ganschow, and R. Bertram. "²⁶Al Tracer Diffusion in Nominally Undoped Single Crystalline α-Al₂O₃." Defect and Diffusion Forum 323-325 (April 2012): 75–79. http://dx.doi.org/10.4028/www.scientific.net/ddf.323-325.75.

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Simultaneous18O and26Al tracer diffusion experiments were performed in nominally undoped single crystalline α-Al2O3. The results clearly show that the bulk diffusivity of aluminium is much higher than the bulk diffusivity of oxygen in nominally undoped alumina. Comparing the26Al tracer diffusivities of Ti doped (300-400 wt. ppm Ti) and nominally undoped single crystalline α-Al2O3one finds that the aluminium bulk diffusivity is insensitive to the Ti doping.

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36

Celina, Mathew C., and Adam Quintana. "Oxygen diffusivity and permeation through polymers at elevated temperature." Polymer 150 (August 2018): 326–42. http://dx.doi.org/10.1016/j.polymer.2018.06.047.

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37

Mehmetoglu, Ü., S. Ateş, and R. Berber. "Oxygen Diffusivity in Calcium Alginate Gel Beads ContainingGluconobacter Suboxydans." Artificial Cells, Blood Substitutes, and Biotechnology 24, no. 2 (January 1996): 91–106. http://dx.doi.org/10.3109/10731199609118877.

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38

Knoner, G., K. Reimann, R. Rower, U. Sodervall, and H. E. Schaefer. "Enhanced oxygen diffusivity in interfaces of nanocrystalline ZrO2*Y2O3." Proceedings of the National Academy of Sciences 100, no. 7 (March 24, 2003): 3870–73. http://dx.doi.org/10.1073/pnas.0730783100.

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39

Nakauchi, Masataka, Takuya Mabuchi, Yuta Yoshimoto, Toshihiro Kaneko, Ikuya Kinefuchi, Hideki Takeuchi, and Takashi Tokumasu. "Molecular Dynamics Study of Oxygen Diffusivity in Catalyst Layer." ECS Transactions 92, no. 8 (July 3, 2019): 23–28. http://dx.doi.org/10.1149/09208.0023ecst.

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40

Zheng, Yong-Fei, and Bin Fu. "Estimation of oxygen diffusivity from anion porosity in minerals." GEOCHEMICAL JOURNAL 32, no. 2 (1998): 71–89. http://dx.doi.org/10.2343/geochemj.32.71.

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41

Yurimoto, Hisayoshi, Masana Morioka, and Hiroshi Nagasawa. "Oxygen self-diffusion along high diffusivity paths in forsterite." GEOCHEMICAL JOURNAL 26, no. 4 (1992): 181–88. http://dx.doi.org/10.2343/geochemj.26.181.

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42

Schotsmans, W., B. E. Verlinden, J. Lammertyn, and B. M. Nicolaï. "DIFFUSIVITY OF OXYGEN AND CARBON DIOXIDE IN FRUIT TISSUE." Acta Horticulturae, no. 566 (December 2001): 521–26. http://dx.doi.org/10.17660/actahortic.2001.566.68.

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43

Chou, H., T. C. Chow, S. F. Tsay, and H. S. Chen. "Diffusivity of Oxygen in Liquid Sn and Ba0.35Cu0.65 Alloys." Journal of The Electrochemical Society 142, no. 6 (June 1, 1995): 1814–19. http://dx.doi.org/10.1149/1.2044198.

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44

Park, Jong-Wan, and Carl J. Altstetter. "The diffusivity and solubility of oxygen in solid palladium." Scripta Metallurgica 19, no. 12 (December 1985): 1481–85. http://dx.doi.org/10.1016/0036-9748(85)90155-3.

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45

Davis, Jacob, Uday Pal, Srikanth Gopalan, Karl Ludwig, and Soumendra Basu. "Measurement of Bulk Oxygen Diffusivity in (La0.8Sr0.2)0.95MnO3±δ." JOM 71, no. 1 (August 16, 2018): 96–102. http://dx.doi.org/10.1007/s11837-018-3099-2.

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46

NANMENG, W. "Oxygen diffusivity in MoMoO2 reference electrode of oxygen probe from electrochemical measurements." Solid State Ionics 18-19 (January 1986): 865–69. http://dx.doi.org/10.1016/0167-2738(86)90277-8.

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47

Cooper, Michael W. D., Samuel T. Murphy, Paul C. M. Fossati, Michael J. D. Rushton, and Robin W. Grimes. "Thermophysical and anion diffusion properties of (U x ,Th 1− x )O 2." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences 470, no. 2171 (November 8, 2014): 20140427. http://dx.doi.org/10.1098/rspa.2014.0427.

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Using molecular dynamics, the thermophysical properties of the (U x ,Th 1− x )O 2 system have been investigated between 300 and 3600 K. The thermal dependence of lattice parameter, linear thermal expansion coefficient, enthalpy and specific heat at constant pressure is explained in terms of defect formation and diffusivity on the oxygen sublattice. Vegard's law is approximately observed for solid solution thermal expansion below 2000 K. Different deviations from Vegard's law above this temperature occur owing to the different temperatures at which the solid solutions undergo the superionic transition (2500–3300 K). Similarly, a spike in the specific heat, associated with the superionic transition, occurs at lower temperatures in solid solutions that have a high U content. Correspondingly, oxygen diffusivity is higher in pure UO 2 than in pure ThO 2 . Furthermore, at temperatures below the superionic transition, oxygen mobility is notably higher in solid solutions than in the end members. Enhanced diffusivity is promoted by lower oxygen-defect enthalpies in (U x ,Th 1− x )O 2 solid solutions. Unlike in UO 2 and ThO 2 , there is considerable variety of oxygen vacancy and oxygen interstitial sites in solid solutions generating a wide range of property values. Trends in the defect enthalpies are discussed in terms of composition and the lattice parameter of (U x ,Th 1− x )O 2 .

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48

Miura, K. "Oxygen Diffusion through Cigarette Paper." Beiträge zur Tabakforschung International/Contributions to Tobacco Research 19, no. 4 (January 1, 2001): 205–8. http://dx.doi.org/10.2478/cttr-2013-0708.

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AbstractOxygen diffusion coefficients in normal and decomposed cigarette papers were measured, and oxygen transfer through the cigarette papers was estimated. The oxygen diffusion coefficient varied with the properties of the cigarette papers, however, the differences in the oxygen transfer coefficient were not very large. The oxygen diffusivity of the cigarette papers did not increase after thermal decomposition. No correlation was found between the oxygen transfer coefficient of the normal paper and the decomposed paper.

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49

JIMENEZ, MÉLANIE, NICOLAS DIETRICH, and GILLES HEBRARD. "A NEW METHOD FOR MEASURING DIFFUSION COEFFICIENT OF GASES IN LIQUIDS BY PLIF." Modern Physics Letters B 26, no. 06 (March 10, 2012): 1150034. http://dx.doi.org/10.1142/s0217984911500345.

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Gas–liquid mass transfer is a major issue in engineering processes such as wastewater treatment or biogas production since this phenomenon is directly linked to their design and efficiency. In recent years, much research has been done in this area but some gaps still remain in our knowledge of gas–liquid transfer, in particular concerning molecular diffusivity. The determination of molecular diffusivity is commonly based on empirical correlations, such as the widely used Wilke and Chang13 expression, valid under specific conditions and with relatively high uncertainties. In the present work, an innovative and promising technique is proposed to determine diffusion coefficients of gases in liquids. This technique is based on visualizing and quantifying oxygen diffusion across a flat gas–liquid interface, in a Newtonian medium, using planar laser induced fluorescence (PLIF) with inhibition. Particle image velocimetry (PIV) experiments were conducted to confirm the hydrodynamic flow field in the liquid phase. Results included the visualization of oxygen diffusion over time, and the quantification of this visualization. The oxygen diffusivity thus determined is in agreement with values found in the literature.

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50

Khirunenko, Lyudmila I., Yu V. Pomozov, Mikhail G. Sosnin, A. V. Duvanskii, S. K. Golyk, Nikolay V. Abrosimov, and H. Riemann. "Oxygen Diffusion in Si_1-xGe_x Alloys." Solid State Phenomena 156-158 (October 2009): 181–86. http://dx.doi.org/10.4028/www.scientific.net/ssp.156-158.181.

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The measurements of stress induced dichroism on oxygen absorption band near 1107 cm-1 in Si1-xGex compounds and subsequent kinetics of the dichroism recovery upon isothermal annealing have been carried out. It has been found that the magnitude of introduced by uniaxial stress dichroism decreases with increasing Ge content. Two components in the dichroism annealing kinetics have been found. On the basis of studying absorption spectra of samples under investigations it was assumed that two components in relaxation correspond to the diffusion of oxygen being in a different nearest environment: the one component corresponds to oxygen surrounded by silicon atoms and the second one to the oxygen the neighbour of which is Ge atom. Diffusivity for each of the components has been determined. It has been shown that the diffusivity of oxygen that is in both of these configurations decreases with increasing Ge content.

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Journal articles on the topic 'Oxygen diffusivity'

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