Variables molecular

Reynolds C A, J W Essex and W G Richards 1992. Atomic Charges for Variable Molecular Conformations. Journal of the American Chemical Society lli 9075-9079. 

The attractive possibility of dissolving the bis-phenol A in caustic soda solution and bubbling phosgene into it is not practical since the polymer is insoluble in the caustic soda and precipitates out at a low and variable molecular weight. 

Organic fouling also affects cation resins, albeit to a lesser degree. The fouling primarily stems from the attachment to the anion exchange site of a variety of low-level organic matter of variable molecular weight that is present in the raw water source. 

Figure 7 shows the results of measurements of adsorption density by Parsonage, etal. [77] on a series of eighteen block copolymers, with poly(2-vinylpyridine) [PVP] anchors and polystyrene [PS] buoys, adsorbed from toluene (selective for PS) of variable molecular weight in each block. The results are presented as the reciprocal square of Eq. 28, that is, as a dimensionless number density of chains ct (d/Rg A)-2. For all but the copolymers of highest asymmetry, Eq. 28 is in good agreement with the data of Fig. 7. The high asymmetry copolymers are in the regime of the data of curves (a) and (c) of Fig. 3 where the large relative size...

Fungal laccases (benzenediokoxygen oxidoreductase, EC 1.10.3.2) belong to the multicopper blue phenoloxidases. They comprise glycosylated proteins expressed in multiple forms and variable molecular weight, ranging from 59 to 110 kDa. Laccase is expressed as multiple constitutive and induced isoenzymes [30, 64]. The enzyme contains four copper atoms (Cu), in different states of oxidation (I, II, III) [65], which play an important role in the catalytic mechanism. Laccase oxidizes different compounds while reducing O2 to H20, a total reduction of four electrons. 

Randic M, Pompe M (2001b) The variable molecular descriptors based on distance related matrices. J. Chem. Inf. Comput. Sci. 41 575-581. 

Using the same procedure Pennisi and Fetters prepared a series of asymmetric polybutadiene (PB) stars in which the third arm was of variable molecular weight [2]. It was found more efficient to add the living PB solution to the meth-yltrichlorosilane linking agent in order to reduce the formation of the coupled byproduct. Similar characterization techniques were also employed in this case. 

The quantitative relationship between these product quality parameters and reactor operating conditions may be the least understood area of polymerization reaction engineering. Table VI summarizes both types of quality control measures. Because of the lack of on-line measurements for most of these product quality variables (molecular or otherwise), control of polymerization reactors is a special challenge. 

Kinetic models exhibit particularities that lead to rather invariant properties not found for dynamical systems in general. Before we discuss these, we remind the reader of the general description of the dynamics of a kinetic model (see also [47, 48]). The mass balances describing the rate of change in the concentrations of the variable molecular species in the network are linear combinations of the rates of the processes in the network, assuming the network can be modeled as a well stirred environment in the absence of noise. In matrix format this leads to ... 

The study of sets of copolymers with a type of block (polystyrene, or polybutadiene) of constant molecular weight and the other of variable molecular weight has shown that, within the stability region for a given structure, the conformation of... 

For SI copolymers, the total thickness (d = dA + dB) of the lamellar structure increases with the total molecular weight of the copolymer (Fig. 25). Furthermore, the study of a set of copolymers with a constant molecular weight of the polystyrene block (23000) and a variable molecular weight for the polyisoprene block (from 8000 to 28000) has shown that the thickness dB of the polyisoprene layer increases with the molecular weight of the polyisoprene block MB (Fig. 26), while the thickness dA of the polystyrene layer is independent of the molecular weight of polyisoprene (Fig. 27). The study of a set of copolymers with the same polyisoprene block (17500) but a variable polystyrene one has shown that the thickness dA of the... 

The relations presented so far have been in terms of summations for greater clarity. The equations given are valid for a distribution in which the variable (molecular weight) assumes only discrete values. However, differences between successive molecular weights are trivial compared to macromolecular sizes and the accuracy with which these values can be measured. Molecular weight distributions can therefore be regarded as continuous, and integral expressions are also valid. 

Mechanical properties of a polymer depend on many variables— molecular weight, molecular weight distribution, morphology, additives, temperature, time, and so on. Mechanical properties of polymers are... 

Molecular Dynamics simulation is one of many methods to study the macroscopic behavior of systems by following the evolution at the molecular scale. One way of categorizing these methods is by the degree of determinism used in generating molecular positions [134], On the scale from the completely stochastic method of Metropolis Monte Carlo to the pure deterministic method of Molecular Dynamics, we find a multitude and increasingly diverse number of methods to name just a few examples Force-Biased Monte Carlo, Brownian Dynamics, General Langevin Dynamics [135], Dissipative Particle Dynamics [136,137], Colli-sional Dynamics [138] and Reduced Variable Molecular Dynamics [139]. 

J. Turner, P. Weiner, B. Robson, R. Venugopal, H. Schubele III, and R. Singh, Reduced Variable Molecular Dynamics, J. Comput. Chem., 16(1995), 1271-1290. 

Wide chemical variation is possible within the intermediate types as well. The ethoxylated resin group demonstrates variable molecular weight on its resin base with different amounts and placement of ethoxylated groups. These structural variations provide a complete range of solubilities, charge neutralization tendencies, solids-wetting characteristics, and costs. 

Since cellulose is derived from a natural polymer, it has variable chain length and thus variable molecular weight. See also Sections 8 and 13. 

Reynolds, C.A., Essex, J.W., and Richards, W.G. (1992) Atomic charges for variable molecular... 

CAS 9003-53-6. (C6I I,Cl ICI I2) . Polymerized styrene, a thermoplastic synthetic resin of variable molecular weight depending on degree of polymerization. 

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