Barium sulfate, interactions with

Some ionic adsorbents show unusu ll properties (see, for example, [15, 58, 68-70]). Belyakova and co-workers [68-70] have proposed barium sulfate as a selective adsorbent They successfully used barium sulfate modified with sodium chloride for separation of some isomers of unsaturated, aromatic hydrocarbons, and oxygen- and nitrogen-containing heterocyclic compounds [68]. Barium sulfate was prepared by interaction of s< ium sulfate and barium chloride solutions of various concentration present in equimolar proportions. The specific surface areas varied from 2.5 to 8 m /g. To investigate this ionic adsorbent, glass Ccipillary columns (1 mm i.d.) were packed with barium sulfate particles (0.16-0.20 mm). The maximum value of separation selectivity for all xylene isomers was observed on barium sulfate samples modified with 15% sodium chloride solution [69]. According to electron spectroscopy for chemical analysis these samples contained on the surface about 2% of... 

Several studies have considered the influence of filler type, size, concentration and geometry on shear yielding in highly loaded polymer melts. For example, the dynamic viscosity of polyethylene containing glass spheres, barium sulfate and calcium carbonate of various particle sizes was reported by Kambe and Takano [46]. Viscosity at very low frequencies was found to be sensitive to the network structure formed by the particles, and increased with filler concentration and decreasing particle size. However, the effects observed were dependent on the nature of the filler and its interaction with the polymer melt. 

Aqueous solutions encountered in the Iciboratoiy often contain several species that interact with one another and water to yield two or more equilibria that function simultaneously. For example, when water is saturated with sparingly soluble barium sulfate, three equilibria develop ... 

The barium sulfate is a white precipitate. Its formation as a result of mixing two unknown solutions could help you to identify the two reacting solutions. In this ChemLab, you will work with the aqueous solutions of six unknown ionic compounds. By observing the solutions and their interactions, you will be able to determine the identities of the compounds. 

Examples of inert or extender fillers include china clay (kaolin), talc, and calcium carbonate. Calcinm carbonate is an important filler, with a particle size of about 1 pm. It is a natural product from sedimentary rocks and is separated into chalk, limestone, and marble. In some cases, the calcium carbonate may be treated to improve interaction with the thermoplastic. Glass spheres are also used as thermoplastic fillers. They may be either solid or hollow, depending on the particular application. Talc is a filler with a lamellar particle shape. It is a namral, hydrated magnesium silicate with good slip properties. Kaolin and mica are also natural materials with lamellar structures. Other fillers include woUastonite, silica, barium sulfate, and metal powders. Carbon black is used as a filler primarily in the rnbber industry, but it also finds application in thermoplastics for conductivity, for UV protection, and as a pigment. Fillers in fiber form are often used in thermoplastics. Types of fibers inclnde cotton, wood flour, fiberglass, and carbon. Table 1.3 shows the fillers and their forms. An overview of some typical fillers and their effect on properties is shown in Table 1.4. Considerable research interest exists for the incorporation of nanoscale fillers into polymers. This aspect will be discussed in later chapters. 

Barium sulfate surfaces, interactions with polyelectrolyte crystal-growth inhibitors, 182-191... 

Components in the invading water-based filtrate and in the formation waters may react to form insoluble precipitates which can block the pores and give rise to skin damage. The scale can be formed by interaction of calcium-based brines with carbon dioxide or sulfate ions in the formation water. Alternatively sulfate ions in the invading fluid may react with calcium or barium ions in the formation water. Analysis of the formation water can identify whether such a problem may arise. 

Derivation Interaction of solutions of barium bromide and zinc sulfate, with subsequent crystallization. 

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