And hydrodynamic properties

The effects of the concentration of divinylbenzene on pore-size distribution and surface areas of micropores, mesopores, and macropores in monosized PS-DVB beads prepared in the presence of linear polymeric porogens have been studied (65). While the total surface area is clearly determined by the content of divinylbenzene, the sum of pore volumes for mesoforms and macropores, as well as their pore-size distribution, do not change within a broad range of DVB concentrations. However, the more cross-linked the beads, the better the mechanical and hydrodynamic properties. 

Monkos, Karol 2005. A comparison of solution conformation and hydrodynamic properties of equine, porcine and rabbit serum albumin using viscometric measurements. Biochimica et Biophysica Acta 1748,100-109. 

Sato, T., Norisuye, T., and Fujita, H., Double stranded helix of xanthan dimensional and hydrodynamic properties in 0.1 M aqueous sodium chloride,... 

The results of this study clearly show the complex dependence of the flocculation process on polymer dosage and charge density. It is seen that the form of dependence varies markedly among the responses monitored. In addition to the factors studied here, it can also be expected to depend upon several other physicochemical conditions of the system, including the type of mixing. The final state of flocculation achieved by a mineral/polymer system will depend upon many interactions in the system as determined by various chemical and hydrodynamic properties of the particles, polymer, dissolved organics and the fluids. 

France, R.M. Sellers, D.S. Grossman, S.H. Purification, characterization, and hydrodynamic properties of arginine kinase from gulf shrimp (Pe-naeus aztecus). Arch. Biochem. Biophys., 345, 73-78 (1997)... 

Every ozonation process where gaseous ozone is transferred into the liquid phase and where it subsequently reacts, involves physical and chemical processes which need to be considered in modeling. Physical processes include mass transfer and hydrodynamic properties of the reaction system, e. g. gas- and liquid-phase mixing. Chemical processes include, ideally, all direct and/or indirect reactions of ozone with water constituents. Of course these processes cannot be seen independently. For example, fast reactions can enhance mass transfer. 

Toonkool, P., Regan, D. G., Kuchel, P. W., Morris, M. B., and Weiss, A. S. (2001a). Thermodynamic and hydrodynamic properties of human tropoelastin. Analytical ultracentrifuge and pulsed field-gradient spin-echo NMR studies. / Biol. Chem. 276, 28042-28050. 

To provide a specific example, Imae and Ikeda (ref. 479) state that amine oxide is very hydrophilic and can constitute a good polar head group for nonionic surfactants at neutral pH. Dimethyl-dodecylamine oxide was first prepared by Hoh et al. (ref. 494), and its surface-active properties in aqueous solutions were investigated by measurements of surface tension (ref. 495), light scattering (ref. 496-498), and hydrodynamic properties (ref. 499). It was found that dimethyldodecylamine oxide can form only spherical micelles in water and aqueous NaCl solutions, when the micelle concentration is dilute (ref. 496,498). Similarly, the homolog dimethyltetradecylamine oxide forms only spherical micelles in water (ref. 496). 

F.E. Bailey and J.V. Koleske, Configuration and hydrodynamic properties of the polyoxyethylene chain in solution, in M.J. Schick (Ed.), Nonionic Surfactants, Dekker, New York, 1967, pp. 794-822. 

Homopolymerization of macromonomer provides regular star- or comb-shaped polymers with a very high branch density as shown in Fig. 1 a,c,e. Such polymacromonomers, therefore, are considered to be one of the best models for understanding of branched architecture-property relationships. Their properties are expected to be very different from the corresponding linear polymers of the same MW both in solution and the bulk state. Indeed, during the past decade, remarkable progress has been accomplished in the field of static, dynamic, and hydrodynamic properties of the polymacromonomers in dilute and concentrated solutions, as well as by direct observation of the polymers in bulk. 

Steele, J. C. H., Jr., and Reynolds, J. A., Molecular weight and hydrodynamic properties of apolipoprotein B in guanidine hydrochloride and sodium dodecyl sulfate solutions. J. Biol. Chem. 254, 1639-1643 (1979). 

Dalgleish, D. G., and Morris, E. R. (1988). Interactions between carrageenans and casein micelles electrophoretic and hydrodynamic properties of the particles. Food Hydrocoll. 4 311-320. 

H 9 Hunt, M. L., S. Newman, H. A. Scheraga and P. J. Flory Dimensions and hydrodynamic properties of cellulose trinitrate molecules in dilute solutions. J. Phys. Chem. 60, 1278 (1956). 

Reactants and products must diffuse through high-molecular-weight liquid hydrocarbons during FT synthesis. The liquid phase may be confined to the mesoporous structure within catalyst pellets or extend to the outer surface and the interstitial spaces between pellets, depending on the reactor design and hydrodynamic properties. In packed-bed reactors, the characteristic diffusion distance equals the radius of the pellets plus the thickness of any liquid boundary layer surrounding them. Intrapellet diffusion usually becomes... 

The study of the textural properties of catalyst supports is of primary importance in terms of understanding the catalytic phenomena involved in petrochemical and refining industry processes. In fact, characteristics, such as the specific surface area, pore size or total porous volume will be useful in various stages of a catalyst s existence its preparation (deposition of active phases), its use in catalysis and its regeneration. They directly influence the physicochemical properties of the solid as well as surface reactivity, shape selectivity and hydrodynamic properties. 

Tables 1—3 give the values of molecular parameters characterizing the equilibrium rigidity and hydrodynamic properties of molecules of some rigid-chain polymers obtained from viscometric and diffusion-sedimentation measurements of their dilute solutions.

Flow birefringence is a widely used method for the investigation of optical, conformational and hydrodynamic properties of molecules of flexible-chain polymers in solution. The experimental and eoretical material avaEable is very comprehensive and has been considered in many reviews providing the basis for the... 

Fig. 17. Molecule with an axial symmetry of optical and hydrodynamic properties in a laminar flow. X flow direction Y direction of velocity gradient Z direction of obs ation 1 axis of symmetry of the molecule...

The situation is more favourable for the study of EB in solutions of flexible-chain polyelectrolytes for which the value of K may be higher by several orders of msg-nitude than for molecules bearing no charge This seems plausible since the uncoiling of a flexible-chain polyion by electrostatic repulsion of ionc enic groups increases the persistent length of the chain and the optical and hydrodynamic properties of the molecule approach those of a rigid-chain polymer ... 

A similar analysis of the shape of curves Y(Tlrj) for labeled polyamic acid and numberical calculations of the rotatory diffusion coefficients of its units show that the relaxation behavior of a chain is similar to that of a model chain with free internal rotations. This result is in agreement with the data on other conformational and hydrodynamic properties of PAA ° and with theoretical conformational... 

Fig. 10.2. Comparison of optical and hydrodynamic properties of CdTe quantum dots (2.5 nm) solubilized in water with an amphiphilic polymer (octylamine-modified polyacrylic acid) or a multidentate polymer ligand, (a) Absorption (blue curves) and fluorescence emission red curves) spectra of CdTe quantum dots with amphiphilic polymer upper) or multidentate polymer lower) coatings, (b) Dynamic light scattering size data of quantum dots with amphiphilic polymer blue curve) and multidentate polymer green curve) coatings. PL Photoluminescence, AU Arbitrary units. All samples were dissolved in phosphate buffered saline...

From this emulsion particle model, it was possible to predict the lipoprotein composition, buoyant density, and hydrodynamic properties of the LDL as a function of lipoprotein size, given the partial specific volumes of the lipid, protein, and carbohydrate components. A cross-sectional slice through the model is shown in Fig. 3 as two concentric circles, representing the hydrophobic core surrounded by a monolayer of phospholipid, cholesterol, and protein. The model parameters are given in the footnote to Table II and include the thickness of the shell, the... 

We conclude that the emulsion particle model provides a satisfactory description of the composition, size, density, and hydrodynamic properties of normal human LDL isolated by density gradient centrifugation. 

Radeva, T., Petkanchin, 1., and Varogui, R., Electrical and hydrodynamic properties of colloid-polymer surface layers investigated by electro-optics, Langmuir, 9, 170, 1993. 

The second part is devoted to adsorption of polyelectrolytes at interfaces and to flocculation and stabilization of particles in adsorbing polymer solutions. A recent theory of the electrostatic adsorption barrier, some typical experimental results, and new approaches for studying the kinetics of polyelectrolyte adsorption are presented in the first chapter of this part. In the following chapters, results are collected on the electrical and hydrodynamic properties of colloid-polyelectrolyte surface layers, giving information on the structure of adsorbed layers and their influence on the interactions between colloidal particles examples and mechanisms are analyzed of polyelectrolyte-induced stabilization and fragmentation of colloidal aggregates ... 

In a dilute protein solution, the nano length scale or the molecular structure of protein molecules determines the thermodynamic equilibrium between protein-protein and protein-water interactions. The consequent surface and hydrodynamic properties of proteins are resulted from the proportion of hydrophobic, hydrophilic, and charged amino acid residues. For example, caseins could adopt a random coil structure due to their flexible structure as a result of phosphorylated serine residues caseins indeed lack the ordered structures of a-helix, 3-sheet, and 3-turn found in globular proteins. This gives rise to better multifunctionality of caseins over globular proteins. 

An expression for the Kerr constant of a solute has been derived by O Konski (14) by assuming a rigid molecule with the same symmetry axis for electric, optic, and hydrodynamic properties. This derivation has proved useful in the study of rigid macromolecules since it allows a clean separation of the electrical factors responsible for the orientation of the molecule. 

The mean-field effect of the environment can be included in biomolecular simulations simply by adding an expression for the solvation free energy of an instantaneous solute conformation to a given molecular mechanics force field [1]. Such an implicit solvent potential addresses the thermodynamic component of solute-solvent interactions. Kinetic and hydrodynamic properties may be reintroduced through the use of Langevin dynamics where coupling with a temperature bath is implemented through stochastic collisions and solvent friction [2,3,18]. 

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