Wagner hydration

In the presence of water vapor, which is the case for precombustion CO2 cap-tiu-e apphcations, the equilibrium defect reaction for water (Eq. (14.40)), also known as Wagner hydration, can also apply, which is characterized by the equi-hbriimi constant Kqh [36] ... 

Principal terpene alcohol components of piae oils are a-terpiueol, y-terpiueol, P-terpiueol, a-fenchol, bomeol, terpiuen-l-ol, and terpiaen-4-ol. The ethers, 1,4- and 1,8-ciaeole, are also formed by cycli2ation of the p-v( enthane-1,4- and 1,8-diols. The bicycHc alcohols, a-fenchol [512-13-0] (61) and bomeol (62), are also formed by the Wagner-Meerweiu rearrangement of the piaanyl carbonium ion and subsequent hydration. Bomeol is i7(9-l,7,7-trimethylbicyclo[2.2.1]heptan-2-ol [507-70-0]. Many other components of piae oils are also found, depending on the source of the turpentine used and the method of production. 

Also in agreement with a cationic intermediate but not with concerted addition is the fact that Wagner-Meerwein rearrangements sometimes occur during hydration.6... 

RbAl(S04)2 uH20 (c). For the dodecahydrate we have estimated the heat of solution to be —11. The heats of dissociation of the various hydrates have been calculated from the dissociation pressure data of Kraus, Fricke, and Querengasser1 and Ephraim and Wagner.1... 

Burney S, Niles JC, Dedon PC, Tannenbaum SR (1999) DNA damage in deoxynucleosides and oligonucleotides treated with peroxynitrite. Chem Res Toxicol 12 513-520 Burr JG, Wagner BO, Schulte-Frohlinde D (1976) The rates of electron transfer from ClUra " and CIUraH" top-nitroacetophenone. Int J Radiat Biol 29 433-438 Buxton GV, GreenstockCL, Helman WP, Ross AB (1988) Critical review of rate constants for reactions of hydrated electrons, hydrogen atoms and hydroxyl radicals ( OH/ O-) in aqueous solution. J Phys Chem Ref Data 17 513-886... 

A. Schrotter found that the salt loses 16 mols. of water at 100° and it weathers more rapidly in air than the ammonium or potassium salt. F. Ephraim and P. Wagner found the vap. press., p mm., of the hydrate to be ... 

Correlation of the observed onset of Wagner s passivity on alloys like Ni-Cu, Nl-Zn-Cu, and Cu-Ni-Al to the occupancy of the d levels of the alloys is given in support of the theory. According to the theory, the same type of passive film (l.e., M-O-O ) is formed in solutions, interposing a stable barrier between metal and electrolyte, displacing adsorbed H2O and increasing the activation energy for the hydration and dissolution of the metal lattice. Such films... 

To illustrate the influence of surface hydroxyl groups and hydration levels on rubber properties, Wagner (1976) took a series of silicas of different surface areas, hydroxylated to different extents, and then added them to an SBR compound at 50phr (Table 9.19). The author concluded that a reduction in silanol level as a result of an increase in absorbed water will decrease cure time, tensile strength, and abrasion resistance. 

If the aqueous phase contains electrolytes, a relaxation due to the Maxwell-Wagner-Sillars effect will be observed. Since the electrolyte is not incorporated in the clathrate structures, an increased electrolyte concentration in the remaining free water will result, thus changing the dielectric relaxation mode. In Fig. 42 we note that the relaxation time r decreases from the initial 1000 100 ps to a final level of 200 20 ps during hydrate formation. The experimental value of 200 ps corresponds roughly to a 3% (w/v) NaCl solution, as compared with the initial salt concentration of 1% (w/v). 

To study the effects of interaction of starch with silica, the broadband DRS method was applied to the starch/modified silica system at different hydration degrees. Several relaxations are observed for this system, and their temperature and frequency (i.e., relaxation time) depend on hydration of starch/silica (Figures 5.6 and 5.7). The relaxation at very low frequencies (/< 1 Hz) can be assigned to the Maxwell-Wagner-Sillars (MWS) mechanism associated with interfacial polarization and space charge polarization (which leads to diminution of 1 in Havriliak-Negami equation) or the 5 relaxation, which can be faster because of the water effect (Figures 5.8 and 5.9). 

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