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61.
We are proposing a lattice model with chemical input for the computer modelling of the polymer glass transition. The chemical input information is obtained by a coarse graining procedure applied to a microscopic model with full chemical detail. We use this information on Bisphenol-A-Polycarbonate to predict it's Vogel-Fulcher temperature out of a dynamic Monte Carlo Simulation. The microscopic structure of the lattice model is that of a genuine amorphous material, and the structural relaxation obeys the time temperature superposition. 相似文献
62.
We present results of computer simulations by the method of Brownian dynamics of polymeric brushes attached to impenetrable planes. For testing both model and method we have used one polymer brush attached to a repulsive plane and compare some results with Monte Carlo results of Lai and Binder on the bond fluctuation model. We have also studied two polymeric brushes attached to two parallel planes at different distances between planes, and investigate the interplay between the interpenetration of the brushes and the configurational properties of the grafted chains. 相似文献
63.
Matthias Schulz Susanne Tanner Haitham Barqawi Wolfgang H. Binder 《Journal of polymer science. Part A, Polymer chemistry》2010,48(3):671-680
The end‐to‐end cyclization of telechelic polyisobutylenes (PIB's) toward cyclic polyisobutylenes is reported, using either ring‐closing metathesis (RCM) or the azide/alkyne‐“click”‐reaction. The first approach uses bisallyl‐telchelic PIB's (Mn = 1650, 3680, 9770 g mol?1) and Grubbs 1st‐, 2nd‐, and 3rd‐generation catalyst leading to cyclic PIB's in 60–80% yield, with narrow polydispersities (Mw/Mn = 1.25). Azide/alkyne‐“click”‐reactions of bisalkyne‐telechelic PIB's (Mn = 3840 and 9820 g mol?1) with excess of 1,11‐diazido‐undecane leads to the formation of mixtures of linear/cyclic PIB's under formation of oligomeric cycles. Subsequent reaction of the residual azide‐moieties in the linear PIB's with excess of alkyne‐telechelic PEO enables the chromatographic removal of the resulting linear PEO‐PIB‐block copolymers by column chromatography. Thus pure cyclic PIB's can be obtained using this double‐“click”‐method, devoid of linear contaminants. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 671–680, 2010 相似文献
64.
Binder K 《The European physical journal. E, Soft matter》2002,9(3):293-298
After a brief review of the scaling concepts for static and dynamic properties of polymer brushes in good solvents and Theta
solvents, the Monte Carlo evidence is discussed. It is shown that under typical conditions the diameter of the last blob is
of the order of 10-20% of the brush height, and therefore pronounced deviations from the self-consistent field predictions
occur. In bad solvents, lateral microphase separation occurs leading to an irregular pattern of “dimples”. Particularly interesting
is the response of brushes to shear deformation, and the interaction between two interpenetrating brushes. Recent attempts
to understand the resulting shear forces via molecular-dynamics simulations are briefly described, and an outlook on related experiments is given.
Dedicated to Prof. H.E. Stanley on the occasion of his 60th birthday
Received 11 March 2002 and Received in final form 3 June 2002 相似文献
65.
Perry N Binder PM 《Physical review. E, Statistical physics, plasmas, fluids, and related interdisciplinary topics》1999,60(1):459-463
We propose a measure of complexity for symbolic sequences, which is based on conditional probabilities, and captures computational aspects of complexity without the explicit construction of minimal deterministic finite automata (DFA). Moreover, if the sequence is obtained from a dynamical system through a suitable encoding and its equations of motion are known, we show how to estimate the regions of phase space that correspond to computational states with statistically equivalent futures (causal states). 相似文献
66.
Helga Wittmann Johanna Kuhn-Kuhnenfeld H. Binder H. Sterk E. Ziegler 《Monatshefte für Chemie / Chemical Monthly》1971,102(2):404-411
Zusammenfassung IR-spektroskopische Untersuchungen an den Malonesterbetainen1–7 geben Hinweise auf die Schwerpunkte der Ladungsverteilung. Während die Lage der CO-Banden der Betaine1 und2 mit rein aliphatischer Esterkomponente auf vollständige Resonanz zwischen den Estercarbonylen hinweist, ist bei jenen mit aromatischen Estergruppen (4, 5 und7) eine CO-Funktion zu beobachten, die schon auf einen gewissen Ylidanteil schließen läßt. Damit im Einklang stehen auch ihre chemischen Eigenschaften. Z. B. zersetzt sich das Bisphenoxycarbonylbetain4 beim Schmelzpunkt vollständig. Die Thermolyse von1 und2 führt dagegen sowohl zu Picolin- als auch zu Kohlensäureestern. Der Reaktionsmechanismus wird diskutiert.
Herrn Direktor Dr. techn., Dr. rer. nat. h. c., Dr. phil. h. c.W. G. Stoll, Basel, mit besten Wünschen zum 60. Geburtstag gewidmet. 相似文献
Reactions with betain, VI: The chemistry of several malonate betaines
An IR-spectroscopic investigation concerning the malonate betaines1–7 gives an insight in the charge density distribution. The position of the C=O frequencies of the betaines1 and2 with alkyl ester groups shows complete resonance between the ester carbonyls, while with the phenolic esters4,5 and7 and C=O absorption is observed which shows a considerable ylid participation. the chemical properties of the betaines agree with this; e.g. the bis-phenoxycarbonylbetaine4 is decomposed totally at its melting point. However, the thermolysis of1 and2 gives picolinic acid esters and carbonic acid esters. The mechanism of these reactions is discussed.
Herrn Direktor Dr. techn., Dr. rer. nat. h. c., Dr. phil. h. c.W. G. Stoll, Basel, mit besten Wünschen zum 60. Geburtstag gewidmet. 相似文献
67.
68.
H. Urbantke F. Schweiger K. Seeger P. Aichelburg W. Bauer P. Flor P. Schmitt R. Sexl J. Lawrenoe A. Wehrl J. Cigler G. Ecker F. Jelinek N. Hofreiter G. Kowol H. Lausch P. Gerl Ch. Binder H. Muthsam H. C. Reichel 《Monatshefte für Mathematik》1971,75(5):453-480
Ohne Zusammenfassung 相似文献
69.
Zusammenfassung Nach der soeben1 beschriebenen Methode wird gezeigt, wie aus der Temperaturabhängigkeit der gas-chromatographisch gewonnenen Zusammensetzung der Dampfphase thermodynamische Größen, wie die isothermen Partial- und Totaldampf-druckkurven und die freie Überschußenthalpie, gewonnen werden können. Dies gibt einerseits eine Kontrollmöglichkeit von auf anderem Wege erhaltenen Daten wegen der geringen Empfindlichkeit gegenüber Verunreinigungen, andererseits auch einen bequemen Zugang zu noch nicht genügend untersuchten Mehrstoffsystemen. Zur Kontrolle und Illustration der Methode wählten wir das positive Azeotrop Benzol-Äthanol und das negative Azeotrop Dioxan-Essigsäure.
Mit 8 Abbildungen 相似文献
A gas chromatographic study of vapor phases, IV.: Determination of the thermodynamic functions of multicomponent systems
On the basis of a method outlined in a preceding1 paper it is shown how the temperature dependence of the composition of the vapour phase, obtained by gas chromatography, can be used to determine thermodynamic quantities as isothermal partial and total vapour pressures and the excess free enthalpy of mixing. On the one hand this permits to check data obtained by other methods since gas chromatography is less sensitive to impurities, on the other hand it opens a convenient access to insufficiently treated multicomponent systems. For an illustration of the method the positive azeotropic system benzene—ethanol and the negative system dioxane-acetic acid was chosen.
Mit 8 Abbildungen 相似文献
70.