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31.
32.
String vertices,V, are shown to satisfy a new type of overlap equation of the form
as well as corresponding equations forA
n andB
n cycles. A special case of such an equation, when integrated, is shown to be the Hirota equation for the K–P hierarchy. 相似文献
33.
The effect of polymers on the phase behavior of balanced microemulsions: diblock-copolymer and comb-polymers 总被引:1,自引:0,他引:1
The effect of some amphipilic diblock-copolymers and comb-polymers on a balanced Winsor III microemulsion system is investigated with the quaternary system n-octyl-β-d-glucoside/1-octanol/n-octane/D2O as basis system. The diblock-copolymers are polyethyleneoxide-co-polydodecenoxide (PEO
x
PEDODO
y
) and polyethyleneoxide-co-polybutyleneoxide (PEO
x
PEBU
y
), constituted of a straight chain hydrophilic part and a bulky hydrophobic part. Addition of the diblock-copolymer leads to an enhancement of the swelling of the middle phase by uptake of water and oil; a maximum boosting factor of 6 was obtained for PEO111PEDODO25. Nuclear magnetic resonance diffusometry yields the self-diffusion coefficients of all the components in the system. The diffusion experiments provide information on how the microstructure of the bicontinuous microemulsion changes upon addition of the polymers. The reduced self-diffusion coefficients of water and oil are sensitive to the type of polymer that is incorporated in the film. For the diblock-copolymers, as mainly used here, the reduced self-diffusion coefficient of oil and water will respond to how the polymer bends the film. When the film bends away from water, the reduced self-diffusion of the water will increase, whereas the oil diffusion will decrease due to the film acting as a barrier, hindering free diffusion. The self-diffusion coefficient of the polymer and surfactant are similar in magnitude and both decrease slightly with increasing polymer concentration. 相似文献
34.
We have used molecular dynamics simulations to study the physical properties of modified TIP3P water model included in the CHARMM program, using four different methods-the Ewald summation technique, and three different spherical truncation methods-for the treatment of the long-range interactions. Both the structure and dynamics of the liquid water model were affected by the methods used to truncate the long-range interactions. For some of the methods artificial structuring of the model liquid was observed around the cutoff radius. The model liquid properties were also affected by the commonly applied temperature control methods. Four different methods for controlling the temperature of the system were studied, and the effects of these methods on the bulk properties for liquid water were analyzed. The system size was also found to change the dynamics of the model liquid water. Two control simulations with the SPC/E water model were carried out. The self-diffusion coefficient (D), the radial distribution function (g(OO)), the distance dependent Kirkwood G-factor [G(k)(r)] and the intermolecular potential energy (E(pot)) were determined from the different trajectories and compared with the experimental data. 相似文献
35.
V. Karimäki R. Kinnunen M. Korkea-aho J. Tuominiemi G. W. van Apeldoorn D. Harting D. J. Holthuizen B. J. Pijlgroms P. Johnson P. Mason P. Michaelides Ch. Michaelidou H. Muirhead G. D. Patel G. Ekspong T. Moa S. Nilsson 《Zeitschrift fur Physik C Particles and Fields》1981,9(2):117-129
Inclusive production of ?0,K *±(892), andf is studied in \(\bar p\) p interactions at 12 GeV/c. The inclusive cross sections for ?0,K *±(892), andf are found to be 6.7±0.3 mb, 1.0±0.2 mb, and 1.4±0.3 mb, respectively. The differential cross sections are presented as a function of c.m. rapidity, Feynmanx and square of the transverse momentump T 2 . Comparison with the correspondingpp data shows some interesting differences which can be attributed to the \(\bar p\) p annihilation. The results are compared with the predictions of the quark fusion model. 相似文献
36.
Patrik Nilsson 《Journal of organometallic chemistry》2005,690(18):4197-4202
An investigation of the kinetics of the Heck reaction between 4-iodoanisole and styrene catalysed by {cis-1,3-bis[(di-tert-butylphosphino)methyl]-cyclohexane} palladium (II) iodide (1) has been performed in DMF-d7 solution. Based on mercury poisoning experiments a heterogeneous palladium catalyst formed from the pre-catalyst is proposed. Saturation behaviour with respect to the olefin concentration suggests a mechanism consisting of a pre-equilibrium association of the olefin followed by a rate determining reaction with aryl halide. The equilibrium constant for the olefin association, K1, and the rate constant for the subsequent oxidative addition step, k2, were determined to (5.7 ± 2.5) × 10−3 and 18.4 ± 2.7 M−1 s−1, respectively. 相似文献
37.
Ohne Zusammenfassung 相似文献
38.
De La Rosa Nathaly Kristiansson Per Nilsson E. J. Charlotta Ros Linus Pallon Jan Skogby Henrik 《Journal of Radioanalytical and Nuclear Chemistry》2018,317(1):253-259
Journal of Radioanalytical and Nuclear Chemistry - Proton-induced reaction (p,α) is one type of nuclear reaction analysis (NRA) suitable especially for light element quantification.... 相似文献
39.
40.
Jun Kawahara Peter Andersson Ersman David Nilsson Kazuya Katoh Yasukazu Nakata Mats Sandberg Marie Nilsson Göran Gustafsson Magnus Berggren 《Journal of Polymer Science.Polymer Physics》2013,51(4):265-271
A flexible electrochromic active matrix addressed display, including 8 × 8 pixels, is demonstrated by using solution processing based on standard printing and coating manufacturing techniques. Each organic electrochromic display (OECD) pixel and its corresponding organic electrochemical transistor (OECT) are located on different sides of the flexible PET substrate. Electronic vias generated through the plastic substrate connects each OECD pixel with one addressing OECT. When comparing this display with actively addressed OECDs with all its components located on the same side, the present approach based on this electronic via substrate provides an enhanced pixel resolution and a relatively more simplified manufacturing process. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012 相似文献