Liquid Hydrate Type

The conclusions drawn on the basis of the dielectric loss analysis of liquid samples, support the interpretation that a very gradual confluence of the different types of dispersions takes place.Such an interpretation could explain the instauration of polydispersed samples in terms of the coexistence, at equilibrium, first, of micellar aggregates with w/o microemulsion droplets and, successively, of a microemulsion with l-I O-per hydrophilic group monolayer, in equilibrium with a hydrated type of microemulsion (U-water molecule per polar head of the surfactant hydrophilic groups monolayer). The latter interpretation is in accordance with Steinbach and Sucker findings that the two types of structures ( 1-HpO and U-HgO molecule), may coexist at equilibrium (23.). 

Steric criteria are also valuable to explain the formation of liquid hydrate clathrates (Fig. 3, 16.2.2.1). They appear for molecules having dimensions between the free diameters of the largest voids of types I and II structures, d, 2 and dn,2- The situation is the same for double liquid hydrates, but here a type I structure is theoretically possible in some cases, e.g., CHjBr, COS and CH3I. For molecules with dimensions >690 pm, no hydrates are formed. This selectivity in encaging certain molecules but not others has been used for fractionation of natural gas by clathration and for desalination of sea water "... 

Figure 3.10 Schematic representation of ocean storage options. In dissolution type ocean storage, the carbon dioxide rapidly dissolves in the ocean water, whereas in lake type ocean storage, the carbon dioxide is initially a liquid on the sea floor, soon crystallizing as a hydrate. Given sufficient time, all forms of carbon dioxide - gas, liquid, hydrate - will dissolve in the water.

Increasing Demand for Hydrated-Type Liquid- plied Membrane Waterproofing Materials (in Japanese), The Bosui Journal, 21(10) 43-46 (Nov. 1990)... 

Type I silicon clathrates and type II silicon clathrates were found to be isostructural to gas hydrates such as (Cl2)8(H20)46 and to liquid hydrate, such as (H2S)i6(CCl4)s(H20)i36 respectively [Reny et al., 2002). There are also type III silicon clathrates, e.g. Ba24Siioo type I and III are superconducting. 

Place 80 g, of hydroxylamine sulphate (or 68-5 g. of the hydrochloride), 25 g. of hydrated sodium acetate, and 100 ml. of water in a 500 ml. flask fitted with a stirrer and a reflux water-condenser, and heat the stirred solution to 55-60°. Run in 35 g (42 nil,) of -hexyl methyl ketone, and continue the heating and vigorous stirring for ij hours. (The mixture can conveniently be set aside overnight after this stage.) Extract the oily oxime from the cold mixture twice with ether. Wash the united ethereal extract once with a small quantity of water, and dry it with sodium sulphate. Then distil off the ether from the filtered extract, preferably using a distillation flask of type shown in Fig. 41 (p. 65) and of ca, 50 ml, capacity, the extract being run in as fast as the ether distils, and then fractionally distil the oxime at water-pump pressure. Collect the liquid ketoxime, b.p. 110-111713 mm. Yield, 30-32 g. 

Gels. Amorphous hydrated silicas of a purity and stmcture typical of those used ia type 1 dentifrices and the liquid portion (humectant system) of type 1 dentifrices both have approximately the same refractive iadex, ie, about 1.47. As a result, the type 1 dentifrices represented ia Table 1 are inherently transparent or translucent. In the marketplace it has become popular to refer to such dentifrices as gels. For marketing reasons some companies have chosen to opacify these products, with titanium dioxide, for example. The opacified products are identical ia functionality, stmcture, and all other ways, except opacity, to their translucent or transparent counterparts. 

In 1810 Davy discovered chlorine hydrate when cooling a saturated solution of chlorine in water below 9°C. Research by Villard, de Forcrand and many others subsequently showed that this type of hydrate can be formed by water with a large number of gases or volatile liquids such as Cl2, Br2, H2S, C02, CH4, CHC13 and again the inert gases A, Kr, Xe. It was further established that the process... 

Let us consider a clathrate crystal consisting of a cage-forming substance Q and a number of encaged compounds ( solutes ) A, B,. . ., M. The substance Q has two forms a stable modification, which under given conditions may be either crystalline (a) or liquid (L), and a metastable modification (ft) enclosing cavities of different types 1,. . ., n which acts as host lattice ( solvent ) in the clathrate. The number of cavities of type i per molecule of Q is denoted by vt. For hydroquinone v — for gas hydrates of Structure I 1/23 and v2 = 3/23, for those of Structure II vx = 2/17 and v2 = 1/17. 

A solid emulsion is a suspension of a liquid or solid phase in a solid. For example, opals are solid emulsions formed when partly hydrated silica fills the interstices between close-packed microspheres of silica aggregates. Gelatin desserts are a type of solid emulsion called a gel, which is soft but holds its shape. Photographic emulsions are gels that also contain solid colloidal particles of light-sensitive materials such as silver bromide. Many liquid crystalline arrays can be considered colloids. Cell membranes form a two-dimensional colloidal structure (Fig. 8.44). 

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