Resinous substances Subject

The first fractionation of urinary ampholytes in this way was carried out by Boulanger et al. (BIO) in 1952 with the use of ion-exchange resins. They had designed this procedure previously for the fractionation of ampholytes in blood serum (B8). According to this method, deproteinized urine was subjected to a double initial procedure aiming at the separation of low-molecular weight substances from macro-molecular ones. One of the methods consisted of the fractionation of urinary constituents by means of dialysis, the second was based on the selective precipitation of urinary ampholytes with cadmium hydroxide, which, as had previously been demonstrated, permits separation of the bulk of amino acids from polypeptides precipitated under these circumstances. Three fractions, i.e., the undialyzable part of urine, the dialyzed fraction, and the so-called cadmium precipitate were analyzed subsequently. 

The apparent deliberate selection and preparation of certain resources over others (birch bark tar over softwood products) is repeated throughout later European prehistory. Whilst we lack systematic comparative surveys of the physical properties of resin, heated wood and bark products, and bitumen, both choice and preference were being expressed. Yet, even if we had data of this nature, other factors are likely to have come into play. The ability to transform natural materials (such as wood or bark) into discrete organic substances then subject to myriad uses (hafting of tools and weapons just happens to be the most visibly persistent role) would have had a dramatic impact on those who made these substances. 

Noteworthy among the few reports in the literature on this subject is the work of Andersen, Bills, Mishuck, Moe and Schultz [3] on the mechanism of combustion of a mixture of 75% NH4C104 and 25% polyester with styrene. The work of Gro-dzinski [18] who investigated the thermal decomposition of the mixtures of various combustible substances with potassium perchlorate in a ratio of 20/80 by weight, is also of great interest. The combustible ingredients include asphalt and polyester resin from unsaturated (maleic) or saturated acids. 

Colorants are typically defined as pigments and dyes that, when added to plastics, define a specific color. The subject of colorants has been discussed in numerous books and papers. However, in the context of this chapter, a dye is defined as a substance that is soluble in the resin system and produces color only by the absorption of light and no scattering of light. Pigments are not soluble in the resin system and therefore must be mixed into the resin by one of many dispersion processes. Factors such as pigment particle size and ease of mixing or dispersion directly influence their... 

Oddly enough, Kipping had not been concerned primarily with the organosilicon polymers for which his work may best be remembered. He and his students had been interested principally in the preparation and characterization of new compounds, and in the study of their reactions. From such reactions they strove to isolate pure compounds as products, but in certain hydrolytic reactions they constantly were troubled by the appearance of oily or gluelike substances which could not be crystallized and which acted like very complex mixtures when subjected to fractionation procedures. It now seems surprising that they were able to isolate as many of the simpler cyclic and linear polymers as they did, considering the annoying qualities of the resinous masses. 

Although a process of purification is not always applied to these crude oils, it is important and sometimes highly profitable to subject the crude product to a process of rectification. By rectification is meant a redistillation of the oil with steam, this procedure affecting a moderate separation of the undesirable substances which may have been formed. The substances which detract from the odor of the oil are usually left behind in the apparatus as a heavy, malodorous liquid slightly resinous in character. Rectification usually results in a fine, finished product, free from foreign odors, and leaves an oil much more presentable in color as well as in odor and taste. 

It fuses at 400 (752 F.). If further heated it is decomposed into KCl and perchlorate, and at a still higher temperature the perchlorate is decomposed into KCl and 0 2K01O, == Kao, -r KCl -i- O, and KCIO, = KOI -f- 20,. It is a valuable source of O, and a more active oxidant than KNO,. When mixed with readily oxidizable substances, C, 3, P, sugar, tauniu, resins, etc., the mixtures explode when subjected to shock. Witli strong it gives off Cl,0, an explosive yellow gas. It is decomj>osed... 

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