Solution colloids

Wanka G, Floffman FI and Ulbrict W 1990 The aggregation behavior of poly-(oxyethylene)-poly(oxypropylene)-poly-(oxyethylene)-block copolymers in aqueous solutions Colloid Polym. Sc/. 268 101-17... 

Pashley R M and Israelachvili J N 1981 A comparison of surface forces and interfacial properties of mica in purified surfactant solutions Colloids Surf. 2 169-87... 

T. Austad, B. Matre, J. Milter, A. Saevareid, and L. Oyno. Chemical flooding of oil reservoirs Pt 8 Spontaneous oil expulsion from oil-and water-wet low permeable chalk material by imbibition of aqueous surfactant solutions. Colloids Surfaces, Sect A, 137(1-3) 117-129, 1998. 

H. W. Bewersdorff and D. Ohlendorf. The behaviour of drag-reducing cationic surfactant solutions. Colloid Polymer Sci, 266(10) 941-953, October 1988. 

Three major therapeutic options are available to clinicians for restoring circulating blood volume crystalloids (electrolyte-based solutions), colloids (large-molecular-weight solutions), and blood products. 

Therapeutic intravenous (TV) fluids include crystalloid solutions, colloidal solutions, and oxygen-carrying resuscitation solutions. Crystalloids are composed of water and electrolytes, all of which pass freely through semipermeable membranes and remain in the intravascular space for shorter periods of time. As such, these solutions are very useful for correcting electrolyte imbalances but result in smaller hemodynamic changes for a given unit of volume. 

Most descriptions of the dynamics of molecular or particle motion in solution require a knowledge of the frictional properties of the system. This is especially true for polymer solutions, colloidal suspensions, molecular transport processes, and biomolecular conformational changes. Particle friction also plays an important role in the calculation of diffusion-influenced reaction rates, which will be discussed later. Solvent multiparticle collision dynamics, in conjunction with molecular dynamics of solute particles, provides a means to study such systems. In this section we show how the frictional properties and hydrodynamic interactions among solute or colloidal particles can be studied using hybrid MPC-MD schemes. 

Solutions, colloidal suspensions and emulsions, pumpable solids suspensions, pastes and sludges. 

NH4VO3 solution + colloidal silica + 10%WO3/TiO2 optional + pore building agent => Suspension... 

Interactions of bovine serum albumin and lysozyme with sodium silicate solutions. Colloids and Surfaces B-Biointeifaces, 29, 189-196. 

The above model assumes that both components are dynamically symmetric, that they have same viscosities and densities, and that the deformations of the phase matrix is much slower than the internal rheological time [164], However, for a large class of systems, such as polymer solutions, colloidal suspension, and so on, these assumptions are not valid. To describe the phase separation in dynamically asymmetric mixtures, the model should treat the motion of each component separately ( two-fluid models [98]). Let Vi (r, t) and v2(r, t) be the velocities of components 1 and 2, respectively. Then, the basic equations for a viscoelastic model are [164—166]... 

Initial fluid resuscitation consists of isotonic crystalloid (0.9% sodium chloride or lariated Ringer s solution), colloid (5% Plasmanate or albumin, 6% hetastarch), or whole blood. Choice of solution is based on 02-carrying capacity (e.g., hemoglobin, hematocrit), cause of hypovolemic shock, accompanying disease states, degree of fluid loss, and required speed of fluid delivery. 

Kawai, T Tsutsumi, K. Adsorption characteristic of surfactants and phenol on modified zeolites from their aqueous solutions. Colloid Polymeric Science, 1995 273, 787-792. 

Penners, N.H.G. Koopal, L.K. Lyklema, J. (1986) Interfacial electrochemistry of hematite (0 -Fe2O ) Homodisperse and heterodis-perse solutions. Colloids Surfaces 21 457-468... 

Structure parameters. For a single compound, the structure parameters include the proportion of atoms and their connectivity, the geometric and energetic parameters of bonds, angles, and conformation, and the electronic parameters of electron distribution and polarization. For multicomponent systems of solutions, microstmctural material, and composite material, the additional structure parameters include the proportion of the various components, and the relations of their phases as solutions, colloids, or composite solids. 

Iron and aluminum precipitate out when treated with ammonia and are removed by filtration. Other metals, such as copper, zinc, lead and arsenic are precipitated and removed as sulfides upon passing hydrogen sufide through the solution. Colloidal particles of metaUic sulfides and sulfur are removed by treatment with iron(ll) sulfide. The purified solution of manganese(ll) sulfate is then electrolyzed in an electrolytic cell using lead anode and HasteUoy or Type 316 stainless steel cathode, both of which are resistant to acid. Manganese is deposited on the cathode as a thin film. 

J. Lin, S. Raghavan, D.W. Fuerstenau, The adsorption of fluoride ions by hydroxyapatite from aqueous solution. Colloids Surf. 3 (1981) 357-370. 

Kao RL, Wasan DT, Nikolov AD, Edwards DA (1988) Mechanisms of oil removal form a solid surface in the presence of anionic micellar solutions. Colloid Surf 34 389-398... 

In a recent study, as the first trial case, a liquid injection technique was applied to a dry blending system (25). This introductory application concerns the study of the interaction of particles with injected liquid (solvent, polymer solution, colloidal solution, etc.) and will be reported elsewhere. 

The number of studies on the health effects of fullerenes and carbon nanotubes is rapidly increasing. However, the data on their toxicity are often mutually contradictory. For example, the researchers from universities of Rice and Georgia (USA) found that in aqueous fullerene solutions colloidal nano-C particles were formed, which even at low concentration (approximately 2 molecules of fullerene per 108 molecules of water) negatively influence the liver and skin cells [17-19]. The toxicity of this nano-C aqueous dispersion was comparable to that of dioxins. In another smdy, however, it was shown that fullerene had no adverse effects and, on the contrary, had anti-oxidant activity [20]. Solutions of prepared by a variety of methods up to 200 mg/mL were not cytotoxic to a number of cell types [21]. The contradiction between the data of different authors could be explained by different nano-C particles composition and dispersion used in research. 

Bouldin M, Kulicke W-M, Kehler H (1988) A prediction of the non-Newtonian viscosity and shear stability of polymer solutions Colloid Polym Sci 266 793... 

Finkelmann, H., Lehmann, B. and Rehage, G. Phase behaviour of lyotropic liquid crystalline side chain polymers in aqueous solutions. Colloid Polymer Sci. 260, 56 (1982)... 

Wilkie, J.A. and Hering, J.G. (1996) Adsorption of arsenic onto hydrous ferric oxide effects of adsorbate/adsorbent ratios and co-occurring solutes. Colloids And Surfaces A-Physicochemical and Engineering Aspects, 107, 97-110. 

However, a usable paint may be formed that is not a true solution. When a pigment is combined with a binder, a colloid—a solution in which the solute particles are between 1 and 1,000 nanometers in size—can be formed. Like all solutions, colloids are uniform throughout. Many paints are colloids, so there is a good chance that our pigments will form usable paints when combined with our binders. We shall see ... 

Baigorri, R., Fuentes, M., Gonzalez-Gaitano, G., and Garcia-Mina, J-M. (2007). Analysis of molecular aggregation in humic substances in solution. Colloids Surf. A 302, 301-306. 

Her also noted that in dilute solutions colloidal metal silicates precipitate at a pH slightly below that at which the metal hydroxide alone would be precipitated. The strong tendency for some hydroxides to react with silica is demonstrated by the fact that the addition of 300 p.p.m. of Mg (OH)2 to water will reduce the soluble silica content from 42 to 0.1 p.p.m. Aluminum oxide is capable of reducing the solubility of silica from 170 p.p.m. to 20 p.p.m. Cations capable of forming insoluble silicates will reduce the solubility of amorphous silica. Al3+ at a concentration of 100 p.p.m. reduces the solubility of silica from 120 p.p.m. to 1 p.p.m. at pH 8—9 (Okamoto et al., 1957). 

When the diameter of the particles of a substance dispersed in a solvent ranges Ifom about 10 A to 2000 A, the system is called colloidal solution, colloidal dispersion or simply a colloid. The material with particle size in the colloidal range is said to be in the colloidal state. 

Problem 2 (a) Mention the differences between a true solution, colloidal solution and suspension. 

Liquid ammonia (700-800 ml) is placed in the 2-1 flask. Stimng is started and 400 mg (note 1) of iron(m)nitrate (hydrate) is added, followed after an interval of 10 s by 2 to 4 g of sodium. As soon as the blue colour has disappeared, the remainder of the 1.0 mol of sodium is cut in to the grey to black solution (colloidal zerovalent Fe). The conversion into NaNH2 (compare ref.l) takes, as a rule, 25 to 30 min. The volume of the greyish, coarse suspension which has formed, is about 500 ml. Triphenylmethane (0.5 g) is added whereupon a reddish colour is developed. Acetylene (1 to 1.5 1/min) is introduced with efficient stimng. The suspension gradually disappears (note 2). The introduction of acetylene is stopped (removal of the inlet tube) when the red colour has disappeared. Sometimes the colour may reappear, in that case the introduction of acetylene is recontinued far a short time. 

Ari, T., and Norde, W. (1990) The behaviour of some model proteins at solid-liquid interfaces adsorption from single protein solutions. Colloids Surfaces 51, 1-15. 

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