Salts, alteration

Adding salt to water increases the density of a solution. This effect is discussed in greater detail in the next chapter. As shown in Table 2.3, the presence of salt alters other physical properties. 

The pore volume and surface area of sol-PILB-Cn samples are closer to those of the corresponding MCM41 solid prepared with silica fume and the same surfactant used in the preparation of sol-PILB-Cn, rather than to that of sol PILB. For example, the total pore volume and BET specific surface area of sol-PILB-C16 are 0.84 cm3/g and 756 m2/g, respectively, much larger than those for sol-PILB, 0.24 cm3/g and 404 m2/g, but comparable to those for MCM41-C16, 0.94 cm3/g and 790 m2/g. These results suggest that treatment with surfactants of quaternary ammonium salts alters the structure of the sol pillared clay radically. 

The fact that flame retardants and salts alter the kinetics, as well as the products, of the pyrolysis reactions is confirmed by the investigations of Tang and Neil involving thermogravimetric and differential thermal analysis methods (see Section 11,6 p. 446). These investi-... 

It has been shown that the flame-retardant salts alter the course of decomposition of levoglucosan, and promote the charring of this compound. Also, a mixture of tar and a flame retardant (a combination of boric acid and borax), when coated on a glass tape, behaved like a similarly treated cotton fabric, and was not combustible. ... 

The data and arguments presented indicate that the presence of sea salts alters the atomic absorption signal of these four elements from their response in de-ionized water-acid standards in a consistent manner for each particular element and sea salt concentration. This observation can be used to develop a modified standard addition technique. If a series of curves can be prepared that contain the range of metal and sea salt concentration expected in the samples, correction factors between actual and observed concentrations based on pure water-acid standards can be determined. This modified standard addition technique is illustrated for two of the elements discussed previously. For lead the actual concentration is plotted vs. the calculated concentration for a sea salt range of 1.0-5.0 parts per thousand sodium in Figure 4. This plot was prepared from solutions of known concentrations in a sea water medium. For a sample of unknown lead concentration, within the specified range. 

These various data show that inorganic salts alter the actions of each of the known plant hormones, that instances exist in which salts from opposite ends of the Hofmeister series (or the distabilization/stabiliza-tion series) have opposite effects from one another, and that the characteristics of membranes are altered so that the specific binding of a hormone is changed by the presence of the salt. 

The conception that the hydrophobicity of a protein is the property of its surface is used as the basis of the technique suggested by Melander and Horvath 30). This technique consists of an analysis of the effects of inorganic salts on the aqueous solubility of proteins30). According to the model considered by Melander et al.30), the free energy of solvation of a protein macromolecule in aqueous solution is described by Eq (3) (see above). The presence of a salt alters the protein solubility due to the concentration-dependent effect of the salt on the free energy of formation... 

Sodium chloride has long been used for food preservation. Salt alters both the aroma and the taste of food. Addition of sodium chloride to blended cod muscle accelerates the development of rancidity (Castell et al., 1965 Castell and Spears,... 

Returning to the specific pomt with which we began, namely the question as to whether the presence of neutral salts alters the degree of ionisation of a weak electrolyte it is important to show as quantitatively as possible that the alteration is either nil or practically so... 

Phase of solid in equilibrium with dissolved salt alters at 305 K. 

W. A. Waters (Oxford University) Investigations of the extent to which complexes such as (CuCl)+ and undissociated CuCL affect the chain length in the polymerization associated with the Sandmeyer reaction are in progress at Oxford. It is well known that ions that complex well with cupric, e.g., (CN) , can be introduced into aryl nuclei by the Sandmeyer procedure in preference to chloride even when diazonium chlorides have initially been taken. The system, however, is complicated by the fact that the complexing of cuprous and cupric salts alters the redox potential, and this affects the facility of both stages 1 and 3 of the reaction sequence. The effects of introducing polar substituents into the aryl nuclei (Table I) indicates the importance of such effects. 

A more detailed account of serum bile salt alterations in a variety of specific diseases categories is given elsewhere (1). 

Examples of bile salt alterations in patients with acute alcoholic liver injury are given in Table VI. The changes are quite pronounced, especially during stages of acute alcoholism. In the group shown in Table VI, serum bile salt concentrations declined and the ratio (except for the first patient) increased 10 days following admission. These changes may be interpreted as additional evidence that ethanol itself may have a direct toxic action on... 

Dialkyl H-phosphonates furnish in general two types of metal salts alter appropriate treatment. The first type is obtained through deprotonation of the hydrogen atom of the P-H group and has a phosphite structure. 

Humans not exposed to As and without ingestion of arsenic-containing food excrete As usually as DMAA (80-90%) and only in low amounts as inorganic As (10%) and MMAA (10%). Single doses of arsenic salts alter these ratios during the first days after exposure [35,62,65,66,69]. In biological monitoring of humans not the total As but rather the amounts and ratios of the different arsenic metabolites are proof of arsenic contamination. Dietary As does not influence these ratios [64,69,70]. Around 56-85% of seafood arsenic is excreted in the urine [6,35]. 

The molecular origin of salting-out or salting-in effects is not fully understood. But broadly, the current view is that addition of salts alters the internal structure and hence the solubility power of water. In this context, ions are classified in two groups, namely "structure makers" and "structure breakers" (Cox Wolfenden, 1934). Implicit in this conjecture is that ions influence the long-range structure of water. Whether this conjecture is indeed borne out in experiments is one of the topics of debate in the literature. In this Section, we discuss key aspects of papers on both sides of this debate. 

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