Self-diffusion and tracer diffusion of solutions of flexible polymer chains: a comparison of experimental results with theoretical predictions

1991 ◽  
Vol 24 (1) ◽  
pp. 184-192 ◽  
Author(s):  
Bo Nystrom ◽  
Jaan Roots
Keyword(s):  
Tracer Diffusion ◽  
Polymer Chains ◽  
Experimental Results ◽  
Self Diffusion ◽  
Flexible Polymer ◽  
Theoretical Predictions

Ion Beam Analysis of Diffusion in Polymer Melts

1984 ◽  
Vol 40 ◽  
Author(s):  
P. F. Green ◽  
P. J. Mills ◽  
C. J. Palmstrom ◽  
J. W. Mayer ◽  
E. J. Kramer
Keyword(s):  
Molecular Weight ◽  
Rutherford Backscattering Spectrometry ◽  
Ion Beam ◽  
Depth Profiling ◽  
Kirkendall Effect ◽  
Tracer Diffusion ◽  
Polymer Chains ◽  
Self Diffusion ◽  
Beam Depth ◽  
Good Agreement

AbstractTwo ion beam depth profiling methods have been used to measure the diffusion of polymer chains of molecular weight M into a matrix of polymer of molecular weight P. In the first the displacement xm of Au markers at the original interface of a diffusion couple between polystyrene with P=2×107 and a thin film of PS with M<P is measured using Rutherford backscattering spectrometry. From this modern version of the Kirkendall effect we find x=0.4t8(D*t) 0 5, where D* the tracer diffusion coefficient of the M chains at 174°C, is found to be D*=O.007M−2cm2/sec, in good agreement with the D*=DR expected for the reptation mechanism. Forward recoil spectrometry, a technique in which the energies of recoiling deuterons are detected, is used to obtain concentration profiles, and hence D*, of deuterated PS M-chains diffusing into a hydrogenated PS P-chain matrix. When P>>M, D*=0.008M−2, in good agreement with the marker data. When P<P*(M) however D*; increases greatly as P decreases; P* increases slowly with increasing M. The results are predicted quantitatively by D*=DR+DCR, where DCR=0.10Me2/(Mp 3 ) describes the diffusion of the M-chain by release of its topological constraints (by diffusion of the surrounding P-chains) and Me is an entanglement molecular weight. D* for self-diffusion (M=P) is dominated by reptation except for M's close to Me.

scholarly journals Quantitative Experimental and Theoretical Investigations on the Interaction of Shock Waves with Magnetic Fields

1969 ◽  
Vol 24 (10) ◽  
pp. 1449-1457
Author(s):  
H. Klingenberg ◽  
F. Sardei ◽  
W. Zimmermann
Keyword(s):  
Magnetic Fields ◽  
Shock Waves ◽  
Physical Model ◽  
Spectroscopic Method ◽  
Experimental Results ◽  
Dimensional Theory ◽  
One Dimensional ◽  
Theoretical Investigations ◽  
Theoretical Predictions ◽  
Interaction Of Shock Waves

Abstract In continuation of the work on interaction between shock waves and magnetic fields 1,2 the experiments reported here measured the atomic and electron densities in the interaction region by means of an interferometric and a spectroscopic method. The transient atomic density was also calculated using a one-dimensional theory based on the work of Johnson3 , but modified to give an improved physical model. The experimental results were compared with the theoretical predictions.

scholarly journals Experimental study of the $ \gamma p \rightarrow K^{0}\Sigma^{+}$, $ \gamma n \rightarrow K^{0} \Lambda$, and $ \gamma n \rightarrow K^{0} \Sigma^{0}$ reactions at the Mainz Microtron

2019 ◽  
Vol 55 (11) ◽  
Author(s):  
C. S. Akondi ◽  
K. Bantawa ◽  
D. M. Manley ◽  
S. Abt ◽  
P. Achenbach ◽  
...  
Keyword(s):  
Experimental Study ◽  
Cross Sections ◽  
Differential Cross ◽  
Legendre Polynomials ◽  
Neutral Kaon ◽  
Experimental Results ◽  
Differential Cross Sections ◽  
Theoretical Predictions ◽  
Photoproduction Reactions ◽  
Insight Into

Abstract.This work measured $ \mathrm{d}\sigma/\mathrm{d}\Omega$dσ/dΩ for neutral kaon photoproduction reactions from threshold up to a c.m. energy of 1855MeV, focussing specifically on the $ \gamma p\rightarrow K^0\Sigma^+$γp→K0Σ+, $ \gamma n\rightarrow K^0\Lambda$γn→K0Λ, and $ \gamma n\rightarrow K^0 \Sigma^0$γn→K0Σ0 reactions. Our results for $ \gamma n\rightarrow K^0 \Sigma^0$γn→K0Σ0 are the first-ever measurements for that reaction. These data will provide insight into the properties of $ N^{\ast}$N* resonances and, in particular, will lead to an improved knowledge about those states that couple only weakly to the $ \pi N$πN channel. Integrated cross sections were extracted by fitting the differential cross sections for each reaction as a series of Legendre polynomials and our results are compared with prior experimental results and theoretical predictions.

A Technique for the Laboratory Determination of Recirculation in Single Needle Dialysis

1993 ◽  
Vol 16 (2) ◽  
pp. 63-70 ◽  
Author(s):  
N.A. Hoenich ◽  
P.T. Smirthwaite ◽  
C. Woffindin ◽  
P. Lancaster ◽  
T.H. Frost ◽  
...  
Keyword(s):  
Experimental Data ◽  
Flow Rate ◽  
Experimental Results ◽  
New Technique ◽  
Treatment Efficiency ◽  
Single Lumen ◽  
Theoretical Predictions ◽  
Lumen Catheter ◽  
A New Technique

Recirculation is an important factor in single needle dialysis and, if high, can compromise treatment efficiency. To provide information regarding recirculation characteristics of access devices used in single needle dialysis, we have developed a new technique to characterise recirculation and have used this to measure the recirculation of a Terumo 15G fistula needle and a VasCath SC2300 single lumen catheter. The experimentally obtained results agreed well with those established clinically (8.5 ± 2.4% and 18.4 ± 3.4%). The experimental results have also demonstrated a dependence on access type, pump speeds and fistula flow rate. A comparison of experimental data with theoretical predictions showed that the latter exceeded those measured with the largest contribution being due to the experimental fistula.

Accommodation and Convergence in the Human Eye

1969 ◽  
Vol 2 (3) ◽  
pp. T29-T33 ◽  
Author(s):  
F. M. Toates
Keyword(s):  
Control Systems ◽  
Control Model ◽  
Monocular Vision ◽  
Experimental Results ◽  
After Effects ◽  
Human Eye ◽  
Theoretical Predictions ◽  
Accommodative Convergence ◽  
Effect Of Age

The control systems of accommodation and convergence in the human eye are theoretically examined, together with their interactions which represent accommodative convergence and convergence induced accommodation. A control model is proposed in order to help to understand the system, and it is used to make predictions concerning accommodation and convergence placed in conflict, monocular vision, fusional after-effects and the effect of age and drugs on accommodation and accommodative convergence. In each case the theoretical predictions are compared with established experimental results.

Application of a photodimerizable probe to the forced Rayleigh scattering technique for measurement of self-diffusion of polymer chains

Polymer ◽  
1986 ◽  
Vol 27 (11) ◽  
pp. 1705-1708 ◽  
Author(s):  
Qui Tran-Cong ◽  
Taihyun Chang ◽  
Charles C. Han ◽  
Yasunori Nishijima
Keyword(s):  
Rayleigh Scattering ◽  
Polymer Chains ◽  
Self Diffusion ◽  
Scattering Technique

Adsorption of oxalate on anatase (100) and rutile (110) surfaces in aqueous systems: experimental results vs. theoretical predictions

2009 ◽  
Vol 11 (11) ◽  
pp. 1794 ◽  
Author(s):  
Cecilia B. Mendive ◽  
Thomas Bredow ◽  
Armin Feldhoff ◽  
Miguel A. Blesa ◽  
Detlef Bahnemann
Keyword(s):  
Experimental Results ◽  
Aqueous Systems ◽  
Theoretical Predictions

scholarly journals Adsorption of flexible polymer chains on a surface: Effects of different solvent conditions

2018 ◽  
Vol 148 (20) ◽  
pp. 204901 ◽  
Author(s):  
P. H. L. Martins ◽  
J. A. Plascak ◽  
M. Bachmann
Keyword(s):  
Surface Effects ◽  
Polymer Chains ◽  
Flexible Polymer
Sign in / Sign up

Export Citation Format

Share Document