Articles de revues : « Diffusion en direct »

1

Seljan, Ellen C., et Nicholas Weller. « Diffusion in Direct Democracy ». State Politics & ; Policy Quarterly 11, n^o 3 (31 août 2011) : 348–68. http://dx.doi.org/10.1177/1532440011413087.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

2

Kaur, Shubjeet, Joaquin Cortiella et Charles A. Vacanti. « DIRECT DIFFUSION OF NITROUS OXIDE ». Anesthesiology 89, Supplement (septembre 1998) : 1357A. http://dx.doi.org/10.1097/00000542-199809230-00001.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

3

Khasnabish. « Direct Action, Deliberation, and Diffusion ». Journal for the Study of Radicalism 8, n^o 2 (2014) : 111. http://dx.doi.org/10.14321/jstudradi.8.2.0111.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

4

Khujadze, George, et Martin Oberlack. « Turbulent diffusion : Direct numerical simulation ». PAMM 9, n^o 1 (décembre 2009) : 451–52. http://dx.doi.org/10.1002/pamm.200910198.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

5

Ye, Min. « UTILITY AND CONDITIONS OF DIFFUSION BY DIASPORAS : EXAMINING FOREIGN DIRECT INVESTMENT LIBERALIZATION IN CHINA AND INDIA ». Journal of East Asian Studies 16, n^o 2 (juillet 2016) : 261–80. http://dx.doi.org/10.1017/jea.2016.3.

Texte intégral

Résumé :

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.

Styles APA, Harvard, Vancouver, ISO, etc.

6

Nakagawa, Tsubasa, Isao Sakaguchi, Naoya Shibata, K. Matsunaga, Teruyasu Mizoguchi, Takahisa Yamamoto, Hajime Haneda et Yuichi Ikuhara. « Direct Measurement of Titanium Pipe Diffusion Coefficients in Sapphire ». Materials Science Forum 558-559 (octobre 2007) : 939–42. http://dx.doi.org/10.4028/www.scientific.net/msf.558-559.939.

Texte intégral

Résumé :

The diffusion behavior of Ti3+ along basal dislocations in sapphire has been investigated by SIMS technique. High-density unidirectional dislocations were introduced by the high-temperature mechanical deformation, and Ti3+ ions were subsequently diffused along the dislocations. The SIMS diffusion profiles clearly showed diffusion tail due to the short circuit diffusion along the dislocations called pipe diffusion. Lattice diffusion coefficient and pipe diffusion coefficient of Ti3+ at 1300°C were measured to be 1.0±0.2×10-19 [m2/sec] and 2.0±0.6× 10-13 [m2/sec], respectively.

Styles APA, Harvard, Vancouver, ISO, etc.

7

Rugeley, Cynthia, John Frendreis et Raymond Tatalovich. « Direct democracy, policy diffusion, and medicalized marijuana ». Politics and the Life Sciences 40, n^o 1 (2021) : 72–82. http://dx.doi.org/10.1017/pls.2020.30.

Texte intégral

Résumé :

AbstractVirtually all studies of policy diffusion are based on statutory enactments by state legislatures. But a substantial number of medicalized marijuana laws were initiated through citizen initiatives and ratified by referenda (I&R). This case study suggests that the diffusion of laws adopted by I&R requires two modifications to the conventional model of policy diffusion. First, early policy adoptions must occur through direct democracy so that horizontal diffusion results when those past adoptions by the I&R process lead to future adoptions. Second, the necessity of bypassing institutions of representative government must be operationalized as an interaction between the availability of direct democracy and the precise political variable that blocks legislative enactments.

Styles APA, Harvard, Vancouver, ISO, etc.

8

Yoon, Samson, Bongtae Han et Zhaoyang Wang. « On Moisture Diffusion Modeling Using Thermal-Moisture Analogy ». Journal of Electronic Packaging 129, n^o 4 (24 avril 2007) : 421–26. http://dx.doi.org/10.1115/1.2804090.

Texte intégral

Résumé :

Thermal-moisture analogy schemes for a moisture diffusion analysis are reviewed. Two schemes for practical applications are described using the governing equations of heat and mass diffusions: (1) direct analogy and (2) normalized analogy. The schemes are implemented to define valid domains of application. The results corroborate that the direct analogy is valid only for single-material systems, but the normalized analogy can be extended to multimaterial systems if thermal loading conditions are isothermal, spatially as well as temporally.

Styles APA, Harvard, Vancouver, ISO, etc.

9

Carpenter, J. R., T. Sommer et A. Wüest. « Stability of a Double-Diffusive Interface in the Diffusive Convection Regime ». Journal of Physical Oceanography 42, n^o 5 (1 mai 2012) : 840–54. http://dx.doi.org/10.1175/jpo-d-11-0118.1.

Texte intégral

Résumé :

Abstract In this paper, the authors explore the conditions under which a double-diffusive interface may become unstable. Focus is placed on the case of a cold, freshwater layer above a warm, salty layer [i.e., the diffusive convection (DC) regime]. The “diffusive interface” between these layers will develop gravitationally unstable boundary layers due to the more rapid diffusion of heat (the destabilizing component) relative to salt. Previous studies have assumed that a purely convective-type instability of these boundary layers is what drives convection in this system and that this may be parameterized by a boundary layer Rayleigh number. The authors test this theory by conducting both a linear stability analysis and direct numerical simulations of a diffusive interface. Their linear stability analysis reveals that the transition to instability always occurs as an oscillating diffusive convection mode and at boundary layer Rayleigh numbers much smaller than previously thought. However, these findings are based on making a quasi-steady assumption for the growth of the interfaces by molecular diffusion. When diffusing interfaces are modeled (using direct numerical simulations), the authors observe that the time dependence is significant in determining the instability of the boundary layers and that the breakdown is due to a purely convective-type instability. Their findings therefore demonstrate that the relevant instability in a DC staircase is purely convective.

Styles APA, Harvard, Vancouver, ISO, etc.

10

Mensi, Mounir, Ruslan Ivanov, Tomas K. Uždavinys, Kathryn M. Kelchner, Shuji Nakamura, Steven P. DenBaars, James S. Speck et Saulius Marcinkevičius. « Direct Measurement of Nanoscale Lateral Carrier Diffusion : Toward Scanning Diffusion Microscopy ». ACS Photonics 5, n^o 2 (décembre 2017) : 528–34. http://dx.doi.org/10.1021/acsphotonics.7b01061.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

11

MILLER, RICHARD S., KENNETH G. HARSTAD et JOSETTE BELLAN. « Direct numerical simulations of supercritical fluid mixing layers applied to heptane–nitrogen ». Journal of Fluid Mechanics 436 (10 juin 2001) : 1–39. http://dx.doi.org/10.1017/s0022112001003895.

Texte intégral

Résumé :

Direct numerical simulations (DNS) are conducted of a model hydrocarbon–nitrogen mixing layer under supercritical conditions. The temporally developing mixing layer configuration is studied using heptane and nitrogen supercritical fluid streams at a pressure of 60 atm as a model system related to practical hydrocarbon-fuel/air systems. An entirely self-consistent cubic Peng–Robinson equation of state is used to describe all thermodynamic mixture variables, including the pressure, internal energy, enthalpy, heat capacity, and speed of sound along with additional terms associated with the generalized heat and mass transport vectors. The Peng–Robinson formulation is based on pure-species reference states accurate to better than 1% relative error through comparisons with highly accurate state equations over the range of variables used in this study (600 [les ] T [les ] 1100 K, 40 [les ] p [les ] 80 atm) and is augmented by an accurate curve fit to the internal energy so as not to require iterative solutions. The DNS results of two-dimensional and three-dimensional layers elucidate the unique thermodynamic and mixing features associated with supercritical conditions. Departures from the perfect gas and ideal mixture conditions are quantified by the compression factor and by the mass diffusion factor, both of which show reductions from the unity value. It is found that the qualitative aspects of the mixing layer may be different according to the specification of the thermal diffusion factors whose value is generally unknown, and the reason for this difference is identified by examining the second-order statistics: the constant Bearman–Kirkwood (BK) thermal diffusion factor excites fluctuations that the constant Irwing–Kirkwood (IK) one does not, and thus enhances overall mixing. Combined with the effect of the mass diffusion factor, constant positive large BK thermal diffusion factors retard diffusional mixing, whereas constant moderate IK factors tend to promote diffusional mixing. Constant positive BK thermal diffusion factors also tend to maintain density gradients, with resulting greater shear and vorticity. These conclusions about IK and BK thermal diffusion factors are species-pair dependent, and therefore are not necessarily universal. Increasing the temperature of the lower stream to approach that of the higher stream results in increased layer growth as measured by the momentum thickness. The three-dimensional mixing layer exhibits slow formation of turbulent small scales, and transition to turbulence does not occur even for a relatively long non-dimensional time when compared to a previous, atmospheric conditions study. The primary reason for this delay is the initial density stratification of the flow, while the formation of strong density gradient regions both in the braid and between-the-braid planes may constitute a secondary reason for the hindering of transition through damping of emerging turbulent eddies.

Styles APA, Harvard, Vancouver, ISO, etc.

12

Ditchfield, R., et E. G. Seebauer. « Direct Measurement of Ion-Influenced Surface Diffusion ». Physical Review Letters 82, n^o 6 (8 février 1999) : 1185–88. http://dx.doi.org/10.1103/physrevlett.82.1185.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

13

Yin, Xiaohui, Meishuan Li, Jingjun Xu, Jie Zhang et Yanchun Zhou. « Direct diffusion bonding of Ti3SiC2 and Ti3AlC2 ». Materials Research Bulletin 44, n^o 6 (juin 2009) : 1379–84. http://dx.doi.org/10.1016/j.materresbull.2008.12.002.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

14

Tedjini, M., F. Fournel, H. Moriceau, V. Larrey, D. Landru, O. Kononchuk, S. Tardif et F. Rieutord. « Interface water diffusion in silicon direct bonding ». Applied Physics Letters 109, n^o 11 (12 septembre 2016) : 111603. http://dx.doi.org/10.1063/1.4962464.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

15

Thompson, Aidan P., David M. Ford et Grant S. Heffelfinger. « Direct molecular simulation of gradient-driven diffusion ». Journal of Chemical Physics 109, n^o 15 (15 octobre 1998) : 6406–14. http://dx.doi.org/10.1063/1.477284.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

16

CRANK, J. « The Diffusion of Direct Dyes into Cellulose ». Journal of the Society of Dyers and Colourists 64, n^o 12 (22 octobre 2008) : 386–93. http://dx.doi.org/10.1111/j.1478-4408.1948.tb02492.x.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

17

CKANK, J. « The Diffusion of Direct Dyes into Cellulose ». Journal of the Society of Dyers and Colourists 66, n^o 7 (22 octobre 2008) : 366–74. http://dx.doi.org/10.1111/j.1478-4408.1950.tb02655.x.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

18

Vardoulakis, I., E. Vairaktaris et E. Papamichos. « Subsidence diffusion–convection : I. The direct problem ». Computer Methods in Applied Mechanics and Engineering 193, n^o 27-29 (juillet 2004) : 2745–60. http://dx.doi.org/10.1016/j.cma.2003.10.019.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

19

Carlough, Mark, Sam Hudson, Brent Smith et Dawn Spadgenske. « Diffusion coefficients of direct dyes in chitosan ». Journal of Applied Polymer Science 42, n^o 11 (5 juin 1991) : 3035–38. http://dx.doi.org/10.1002/app.1991.070421122.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

20

LOH, S. W., D. H. ZHANG, C. Y. LI, R. LIU et A. T. S. WEE. « STUDY OF COPPER DIFFUSION INTO TANTALUM AND TANTALUM DIFFUSION INTO COPPER ». International Journal of Modern Physics B 16, n^o 01n02 (20 janvier 2002) : 100–107. http://dx.doi.org/10.1142/s0217979202009512.

Texte intégral

Résumé :

We have carried out direct diffusion measurements of Cu into Ta and Ta into Cu. Thin films of 50nm thickness of Cu were grown onto a thick Ta layer of 1 μm by Ionized Metal Plasma. Samples were annealed in a rapid thermal system from temperatures ranging from 400°C to 800°C for periods of 60s and 180s. The diffusion profile was performed using Secondary ion mass spectroscopy. The Cu diffusion coefficients in Ta can be described by 3.0246 × 10-15 exp(-0.1747eV/kT) at 60s and 2.7532 × 10-15 exp(-0.1737eV/kT) at 180s. The Ta diffusion coefficients in Cu can be described by 2.7532 × 10-15 exp(-0.1773eV/kT) at 60s and 2.1271 × 10-15 exp(-0.1753eV/kT) at 180s. To assure reliability, the extent of both diffusions should be considered in device design and processing.

Styles APA, Harvard, Vancouver, ISO, etc.

21

PRASAD, P. V. SIVA RAMA, et D. P. TEWARI. « Effect of a stochastic electron background on low-m tearing modes ». Journal of Plasma Physics 57, n^o 2 (février 1997) : 247–57. http://dx.doi.org/10.1017/s0022377896004655.

Texte intégral

Résumé :

The effect of a stochastic electron background on the stability of low-m tearing modes is studied. The coherent direct interaction approximation is applied to the drift-kinetic equation in order to include the effects of current density diffusion, electron density diffusion and magnetic field diffusion in the tearing mode equations. It is found that for the m=1 mode in the collisionless regime the magnetic field diffusion destabilizes the mode further, while in the collisional regime these diffusions may not significantly affect the mode; for the m[ges ]2 modes in the collisional and semicollisional regimes the electron density diffusion stabilizes the modes, while in the collisionless regime the effects of current density diffusion and electron density diffusion may balance each other without significantly affecting the modes.

Styles APA, Harvard, Vancouver, ISO, etc.

22

MAEKAWA, Masako, Hiroyuki YOSHIDA et Mamoru NANGO. « Surface diffusion of direct dyes in cellulose membranes. » NIPPON KAGAKU KAISHI, n^o 7 (1989) : 1178–81. http://dx.doi.org/10.1246/nikkashi.1989.1178.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

23

Carpinelli, Joseph M., et B. S. Swartzentruber. « Direct measurement of field effects on surface diffusion ». Physical Review B 58, n^o 20 (15 novembre 1998) : R13423—R13425. http://dx.doi.org/10.1103/physrevb.58.r13423.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

24

Sakellari, Ioanna, Elmina Kabouraki, David Gray, Vytautas Purlys, Costas Fotakis, Alexander Pikulin, Nikita Bityurin, Maria Vamvakaki et Maria Farsari. « Diffusion-Assisted High-Resolution Direct Femtosecond Laser Writing ». ACS Nano 6, n^o 3 (16 février 2012) : 2302–11. http://dx.doi.org/10.1021/nn204454c.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

25

Kumar, Vinod, Sarah Mang et Wolfgang Grodd. « Direct diffusion-based parcellation of the human thalamus ». Brain Structure and Function 220, n^o 3 (22 mars 2014) : 1619–35. http://dx.doi.org/10.1007/s00429-014-0748-2.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

26

Heller, W., A. Filoramo, Ph Roussignol et U. Bockelmann. « Direct measurement of exciton diffusion in quantum wells ». Solid-State Electronics 40, n^o 1-8 (janvier 1996) : 725–28. http://dx.doi.org/10.1016/0038-1101(95)00351-7.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

27

Guzzi, M., J. L. Staehli, M. Capizzi et R. A. Logan. « Electron-Hole Plasma Diffusion in Direct-Gap Semiconductors ? » Europhysics Letters (EPL) 2, n^o 10 (15 novembre 1986) : 813. http://dx.doi.org/10.1209/0295-5075/2/10/011.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

28

Guzzi, M., J. L. Staehli, M. Capizzi et R. A. Logan. « Electron-Hole Plasma Diffusion in Direct-Gap Semiconductors ? » Europhysics Letters (EPL) 2, n^o 7 (1 octobre 1986) : 547–54. http://dx.doi.org/10.1209/0295-5075/2/7/009.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

29

Mogilevsky, R., R. Levi-Setti, B. Pashmakov, Li Liu, K. Zhang, H. M. Jaeger, D. B. Buchholz, R. P. H. Chang et B. W. Veal. « Direct measurements of room-temperature oxygen diffusion inYBa2Cu3Ox ». Physical Review B 49, n^o 9 (1 mars 1994) : 6420–23. http://dx.doi.org/10.1103/physrevb.49.6420.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

30

Kawaguchi, Daisuke. « Direct observation and mutual diffusion of cyclic polymers ». Polymer Journal 45, n^o 8 (23 janvier 2013) : 783–89. http://dx.doi.org/10.1038/pj.2012.231.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

31

Gonatas, C. P., Masaru Ishii, John S. Leigh et John C. Schotland. « Optical diffusion imaging using a direct inversion method ». Physical Review E 52, n^o 4 (1 octobre 1995) : 4361–65. http://dx.doi.org/10.1103/physreve.52.4361.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

32

Hammer, Øyvind. « Diffusion and Direct Signaling Models are Numerically Equivalent ». Journal of Theoretical Biology 192, n^o 1 (mai 1998) : 129–30. http://dx.doi.org/10.1006/jtbi.1998.0654.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

33

Łępicka, Magdalena, et Małgorzata Grądzka-Dahlke. « Direct Current and Pulsed Direct Current Plasma Nitriding of Ferrous Materials a Critical Review ». Acta Mechanica et Automatica 10, n^o 2 (1 juin 2016) : 150–58. http://dx.doi.org/10.1515/ama-2016-0024.

Texte intégral

Résumé :

Abstract Nowadays, the improvement of ferrous materials performance is a problem of high interest. One of well-known wear- and corrosion properties improving technique is plasma nitriding, in which elemental nitrogen is introduced to the surface of a metal part for subsequent diffusion into the material. As a result, a compound, “white” layer and a diffusion zone are formed at the detail’s surface. Most of the authors positively describe the effects of surface ion nitiding. On the other hand, there are also reports on adverse effects of direct current and pulsed direct current plasma nitriding on ferrous materials performance. Therefore, an attempt to provide comprehensive summary on direct current and pulsed direct current ion nitriding and its influence on ferrous materials’ mechanical and corrosion properties has been made. According to the results, some of the technique drawbacks are hard to avoid in mass production.

Styles APA, Harvard, Vancouver, ISO, etc.

34

Pino Muñoz, Daniel, Julien Bruchon, Sylvain Drapier et François Valdivieso. « Direct 3D Simulation of Powder Sintering by Surface and Volume Diffusion ». Key Engineering Materials 554-557 (juin 2013) : 714–23. http://dx.doi.org/10.4028/www.scientific.net/kem.554-557.714.

Texte intégral

Résumé :

Within the general context of solid-state sintering process, this work presents a numericalmodelling approach, at the grain scale, of ceramic grain packing consolidation. Typically, the sinteringprocess triggers several matter diffusion routes that are thermally activated: surface, grain boundaryand volume diffusions. Including this physics into a high-performance computing framework wouldpermit to investigate and to track the changes occurring into a granular packing during sintering. Inperforming this kind of simulations, one will face several challenges: the strong topological changesappear during sintering simulation at the grains scale, the evolution of the structure is mainly drivenby the surface tension phenomena through the Laplace's law, and the mechanical properties of thegrains could, possibly, be different. The proposed numerical simulations are carried out within anEulerian Finite Element framework and the Level-Set method is used to cope with changes in themicrostructure. The results obtained with this numerical strategy are compared with success to theusual geometrical models.

Styles APA, Harvard, Vancouver, ISO, etc.

35

Miyazaki, A., M. Tsuge, H. Hidaka, Y. Nakai et N. Watanabe. « Direct Determination of the Activation Energy for Diffusion of OH Radicals on Water Ice ». Astrophysical Journal Letters 940, n^o 1 (1 novembre 2022) : L2. http://dx.doi.org/10.3847/2041-8213/ac9d30.

Texte intégral

Résumé :

Abstract Using a combination of photostimulated desorption and resonance-enhanced multiphoton ionization methods, the behaviors of OH radicals on the surface of an interstellar ice analog were monitored at temperatures between 54 and 80 K. The OH number density on the surface of ultraviolet-irradiated compact amorphous solid water gradually decreased at temperatures above 60 K. Analyzing the temperature dependence of OH intensities with the Arrhenius equation, the decrease can be explained by the recombination of two OH radicals, which is rate-limited by thermal diffusion of OH. The activation energy for surface diffusion was experimentally determined for the first time to be 0.14 ± 0.01 eV, which is larger than or equivalent to those assumed in theoretical models. This value implies that the diffusive reaction of OH radicals starts to be activated at approximately 36 K on interstellar ice.

Styles APA, Harvard, Vancouver, ISO, etc.

36

Hanson, John R. « Culture Shock and Direct Investment in Poor Countries ». Journal of Economic History 59, n^o 1 (mars 1999) : 1–16. http://dx.doi.org/10.1017/s0022050700022269.

Texte intégral

Résumé :

The role of culture in economic development is experiencing renewed interest among scholars. This study proposes high intercultural transactions costs as a reason for the enduring scarcity of modem capital and technology in poor countries and conducts a statistical test based on the premise that cultural diffusion reduces these costs. The stock of direct investment in poor countries at the end of the colonial era is shown, as predicted, to be directly correlated with the diffusion of Westem culture in the European empires and elsewhere.

Styles APA, Harvard, Vancouver, ISO, etc.

37

Gleditsch, Kristian S., et Mauricio Rivera. « The Diffusion of Nonviolent Campaigns ». Journal of Conflict Resolution 61, n^o 5 (2 septembre 2015) : 1120–45. http://dx.doi.org/10.1177/0022002715603101.

Texte intégral

Résumé :

Existing research has uncovered strong geographical clustering in civil war and a variety of diffusion mechanisms through which violence in one country can increase the risk of outbreaks in other countries. Popular coverage of nonviolent protest often emphasizes regional waves like the 1989 revolutions in Eastern Europe and the Arab Spring. However, most research on nonviolence focuses only on features within countries affecting motivation and opportunities, and we know little about the possible role of diffusion and transnational factors. We detail how nonviolent campaigns in other states can increase nonviolent mobilization and direct action, highlighting important differences in the likely actors for violent and nonviolent direct action and the relevant diffusion mechanisms. We find strong empirical evidence for diffusion in nonviolent campaigns. The effects are largely confined to campaigns in neighboring countries, and there is little evidence of global diffusion. The potential diffusion effects are also specific to whether dissent is violent and nonviolent rather than general political instability. Moreover, we find that the effects of neighboring campaigns on nonviolent direct action apply only in cases with plausible motivation for contesting the government, and the effects are stronger when the regional environment can help expand opportunities for organizing dissent.

Styles APA, Harvard, Vancouver, ISO, etc.

38

Price, Hannah C., Johan Mattsson et Benjamin J. Murray. « Sucrose diffusion in aqueous solution ». Physical Chemistry Chemical Physics 18, n^o 28 (2016) : 19207–16. http://dx.doi.org/10.1039/c6cp03238a.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

39

Wendt, Florian, et Robert Höldrich. « Precedence effect for specular and diffuse reflections ». Acta Acustica 5 (16 décembre 2020) : 1. http://dx.doi.org/10.1051/aacus/2020027.

Texte intégral

Résumé :

Studies on the precedence effect are typically conducted by presenting two identical sounds simulating direct sound and specular reflection. However, when a sound is reflected from irregular surface, it is redirect into many directions resulting in directional and temporal diffusion. This contribution introduces a simulation of Lambertian diffusing reflections. The perceptual influences of diffusion are studied in a listening experiment; echo thresholds and masked thresholds of specular and diffuse reflections are measured. Results show that diffusion makes the reflections more easily detectable than specular reflections of the same total energy. Indications are found that this mainly due to temporal diffusion, while the directional diffusion has little effect. Accordingly, the modeling of the echo thresholds is achieved by a temporal alignment of the experimental data based on the energy centroid of reflection responses. For the modeling of masked threshold the temporal masking pattern for forward masking is taken into account.

Styles APA, Harvard, Vancouver, ISO, etc.

40

Wittmann, Johannes J., Michael Eckardt, Wolfgang Harneit et Björn Corzilius. « Electron-driven spin diffusion supports crossing the diffusion barrier in MAS DNP ». Physical Chemistry Chemical Physics 20, n^o 16 (2018) : 11418–29. http://dx.doi.org/10.1039/c8cp00265g.

Texte intégral

Résumé :

Hyperfine interactions can quench homonuclear spin-diffusion in the direct vicinity of a polarizing agent in dynamic nuclear polarization (DNP). However, under magic-angle spinning (MAS), the same interactions may also enhance the spin-diffusion rates through an electron-driven spin diffusion (EDSD) mechanism introduced here.

Styles APA, Harvard, Vancouver, ISO, etc.

41

MO, Y. W. « SCANNING TUNNELING MICROSCOPY DETERMINATION OF SURFACE DIFFUSION BY DIRECT MEASUREMENT OF DISPLACEMENT DISTRIBUTION ». Modern Physics Letters B 08, n^o 03 (10 février 1994) : 137–42. http://dx.doi.org/10.1142/s0217984994000145.

Texte intégral

Résumé :

A scanning tunneling microscopy method for studying surface diffusion is developed based on measurements of the displacement distribution of adsorbates by “image-anneal-image” cycles which allow direct observation of diffusion process while avoiding potential STM-tip effects. The method is used to study the anisotropic diffusion of Sb dimers on Si(001).

Styles APA, Harvard, Vancouver, ISO, etc.

42

Wang, Yakun, Zhenghui Liu, Wentao Song, Gengzhao Xu, Kebei Chen, Chunyu Zhang, Sha Han, Jianfeng Wang et Ke Xu. « Direct measurement for nanoscale vertical carrier diffusion on semiconductor surface—An approach toward scanning diffusion microscopy ». Journal of Applied Physics 131, n^o 11 (21 mars 2022) : 115701. http://dx.doi.org/10.1063/5.0078871.

Texte intégral

Résumé :

Carrier diffusion properties, including the diffusion length, diffusion coefficient, and carrier lifetime are important for photonic devices. In nitride semiconductors, there are many microscopic structures, which have a strong influence on carrier diffusion. In this paper, a method based on the photo-assisted Kelvin-probe force microscope and the confocal time-resolved photoluminescence spectrum at the same position is developed to map simultaneously the topography and the nanoscale vertical carrier diffusion on the semiconductor surface. On the surface without any dislocations, the hole diffusion length and diffusion coefficient are 161 [Formula: see text] 8 nm and 1.6 [Formula: see text] 0.2 cm2/s, respectively. Near the termination of the dislocation loops on the surface, it can be clearly seen that the diffusion length and diffusion coefficient gradually drop to about 13 [Formula: see text] 5 nm and 0.02 [Formula: see text] 0.01 cm2/s with a spatial resolution of about 100 nm.

Styles APA, Harvard, Vancouver, ISO, etc.

43

Stepovich, Mikhail A., Dmitry V. Turtin, Elena V. Seregina et Veronika V. Kalmanovich. « On the correctness of mathematical models of time-of-flight cathodoluminescence of direct-gap semiconductors ». ITM Web of Conferences 30 (2019) : 07014. http://dx.doi.org/10.1051/itmconf/20193007014.

Texte intégral

Résumé :

Two-dimensional and three-dimensional mathematical models of diffusion and cathodoluminescence of excitons in single-crystal gallium nitride excited by a pulsating sharply focused electron beam in a homogeneous semiconductor material are compared. The correctness of these models has been carried out, estimates have been obtained to evaluate the effect of errors in the initial data on the distribution of the diffusing excitons and the cathodoluminescence intensity.

Styles APA, Harvard, Vancouver, ISO, etc.

44

Azough, Feridoon, Robert Freer, Kate Wright et Robert Jackson. « A computer simulation study of point defects in diopside and the self-diffusion of Mg and Ca by a vacancy mechanism ». Mineralogical Magazine 62, n^o 5 (octobre 1998) : 599–606. http://dx.doi.org/10.1180/002646198547990.

Texte intégral

Résumé :

AbstractComputer simulation techniques have been used to investigate defect formation and the diffusion of Ca and Mg in diopside. It was found that isolated, non-interacting CaO and MgO Schottky defects had the lowest formation energies (3.66 and 3.97 eV respectively); oxygen Frenkel defects are the most favourable oxygen defects (formation energies 3.93 eV). Magnesium and calcium self-diffusion in the c-direction of diopside is easiest by a vacancy mechanism involving either direct jumps along the c-direction, or double jumps in the b-c plane. In the extrinsic regime, diffusion activation energies for Mg are predicted to be 9.82 eV (direct route) and 1.97 eV (double jump route); for Ca diffusion, activation energies are predicted to be 6.62 eV (direct route) and 5.63 eV (double jump route). If additional vacancies (oxygen or magnesium) are present in the vicinity of the diffusion path, Ca migration energies fall to 1.97–2.59 eV. At elevated temperatures in the intrinsic regime, diffusion activation energies of ⩾ 5.95 eV are predicted for Mg self-diffusion and 9.29–10.28 eV for Ca self-diffusion. The values for Ca diffusion are comparable with published experimental data. It is inferred that a divacancy mechanism may operate in diopside crystals.

Styles APA, Harvard, Vancouver, ISO, etc.

45

Belyakova, E., N. Shmidt, V. V. Ratnikov, Alex A. Kamanin, Eun Dong Kim et Sang Cheol Kim. « Diffusion Creep of Silicon during Direct Silicon Wafer Bonding ». Defect and Diffusion Forum 194-199 (avril 2001) : 667–72. http://dx.doi.org/10.4028/www.scientific.net/ddf.194-199.667.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

46

Levy, D., M. Herman, M. Luntz et J. Sadé. « Direct Demonstration of Gas Diffusion into the Middle Ear ». Acta Oto-Laryngologica 115, n^o 2 (janvier 1995) : 276–78. http://dx.doi.org/10.3109/00016489509139308.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

47

Di Blasio, Gabriella, et Alfredo Lorenzi. « Direct and inverse problems in age--structured population diffusion ». Discrete & ; Continuous Dynamical Systems - S 4, n^o 3 (2011) : 539–63. http://dx.doi.org/10.3934/dcdss.2011.4.539.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

48

Khan, S. A., R. L. Mulvaney et R. G. Hoeft. « Direct-Diffusion Methods for Inorganic-Nitrogen Analysis of Soil ». Soil Science Society of America Journal 64, n^o 3 (mai 2000) : 1083–89. http://dx.doi.org/10.2136/sssaj2000.6431083x.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

49

Murota, Akira, Masahiro Tamai, Hiroki Machida et Osamu Asai. « Diffusion Process of Turbidity in Direct Dumping of Soils ». PROCEEDINGS OF HYDRAULIC ENGINEERING 34 (1990) : 217–22. http://dx.doi.org/10.2208/prohe.34.217.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

50

Ittermann, B., H. Ackermann, H. J. Stöckmann, K. H. Ergezinger, M. Heemeier, F. Kroll, F. Mai, K. Marbach, D. Peters et G. Sulzer. « Diffusion of Boron in Copper by Direct-Exchange Mechanism ». Physical Review Letters 77, n^o 23 (2 décembre 1996) : 4784–87. http://dx.doi.org/10.1103/physrevlett.77.4784.

Texte intégral

Styles APA, Harvard, Vancouver, ISO, etc.

Articles de revues sur le sujet « Diffusion en direct »

Créez une référence correcte selon les styles APA, MLA, Chicago, Harvard et plusieurs autres