Similarities absolute thermal

Similarly, in thermal equilibrium, some ionic crystals at a temperature above absolute zero enclose a certain number of Frenkel pair defects, that is, anion and cation interstitials in the structure. Since the concentration of Frenkel pair defects at equilibrium at an absolute temperature, T, obeys the mass action law, then [16]... 

Absolute thermal similarity is difficult to achieve in extrusion processes. This similarity indicates equal temperatures in corresponding locations (Fig. 12.2). A distinction has to be made between processes with small heat effects like low reaction enthalpy or small viscous dissipation and those with high-temperature effects. For... 

Sulfonyl bromides and iodides react similarly - copper-salt catalysis in these cases facilitates the additions but is not absolutely necessary however, it influences the stereochemistry of the additions. Addition of sulfonyl iodides as well as the uncatalyzed thermal addition of sulfonyl bromides to alkynes leads to an exclusive trans-addition, whereas CuBrj catalysis in the latter case causes the formation of cis-addition products to some extent (11-16%) correspondingly, copper-salt catalysis in sulfonyl chloride additions to alkynes leads to the formation of a mixture of Z,E-isomers (equation 40). 

With the development of statistical thermodynamics and the calculations of the entropies of many substances from spectroscopic data, several other substances in addition to hydrogen have been found to have values of molar entropies that disagree with those calculated from thermal data alone [13] (Table 11.1). The discrepancies can be accounted for on the assumption that even near absolute zero not all molecules are in the same state and that tme equilibrium has not been attained. For CO, COCI2, N2O, NO, and CIO3F, the close similarity in the sizes of the atoms makes different... 

Hiskey and co-workers " prepared a series of 0-nifro amino nitrates by reacting the parent aminoalcohols with absolute nitric acid followed by precipitation of the salt with an organic solvent. Two of these compounds, (88) and (89), show similar thermal stability to PETN but are less sensitive to impact. Such compounds show a useful solubility in water and have potential for use as sensitizers in explosive slurries. 

A K-refinement of the 0.12 A y-ray data reproduces the absolute scale poorly when the neutron UtJ thermal parameter values are used (Hansen et al. 1987). The discrepancy can be removed by introduction of a core-tc-parameter, which refines t0 Kcore = 0.988 (2), corresponding to a 1.2% linear expansion. This is supported by a similar result obtained with the LH X-ray data, and related to the scale factor discrepancy noted above. Hansen, Schneider, Yellon, and Pearson (1987), conclude that without independent knowledge of either the scale or the thermal parameters, good agreement with experiment can be achieved, but the resulting scale factor may be in error by as much as 2.5%. 

Spectral parameters of the structured green luminescence (Fig. 4.4d) are absolutely similar to those of luminescence in fluorite after thermal treatment (Tarashchan 1978). Principally, during the calcination of the sedimentary phosphates new mineralogical phases, including fluorite, may be formed. Taking these data into accoimt, it is possible to conclude that after thermal treatment uranium is concentrated in the fluorite lattice in the form of... 

Tetralin hydroperoxide has little or no effect on the thermally or photochemically initiated oxidation of Tetralin, nor are the absolute rate constants for the oxidation of Tetralin (1.7M in chlorobenzene) affected by adding 0.1M [TOOH] (Table I). [Hydrogen-bonded peroxy radicals are either unimportant in this system or have the same reactivity as the peroxy radicals formed in the absence of hydroperoxide. A similar conclusion applies to propagation in cumene and cumene-COOH mixtures (see Table I).]... 

Using fs laser excitation at 620 nm, a 2PC in Y of 0.5ps [399] implicates hot electrons, probably thermalized at Te, as the mechanism for desorption induced by the fs laser (Section 2.6.2). Rotational state distributions are nearly Boltzmann characterized by Tf. The 2PC of internal state distributions was also obtained. Rather surprisingly, significant differences in these 2PC were obtained for T and the state-resolved yield for the two spin-orbit states and this was qualitatively rationalized by a DIMET picture [399]. Where overlap in experiments exist, the qualitative results are similar to those for fs laser induced desorption of NO/Pd(lll) [400,401]. For this latter system, the absolute yield Y is large at typical fluencies used in the experiments and a very hot vibrational distribution was observed (Tv = 2900 K). 

An anomalous X-ray scattering study of (+(-tubocurarine dibromide (73 4MeOH) confirmed the structure and absolute configuration earlier assigned. The N-N distance is 10.66 A (47,48). A purified sample of (+(-tubocurarine chloride (73a), prepared by selective quatemization of (+(-tubocurine (74) (Section V,B,1), gave the anomalous MS behavior previously ascribed to thermal disproportionation or the presence of impurities. In particular, the MS has mle 594 [17%, (M - 15)+, loss of Me] but also 608 (3.7%) and 622 (0.5%). The higher peaks seem to be due to a thermal Hofmann elimination followed by recombination with methyl radicals. Similar behavior is observed with the tertiary bases (—)-curine (75) and (+(-tubocurine (74), and may be general for alkaloids of this skeletal type (49). 

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