ASSIGNED UNCERTAINTIES

Compounds are identified by an IUPAC approved name [93-ano-l], the empirical molecular formula, and the Chemical Abstracts Service Registry Number. A summary table is available for each compound which includes the reported temperature and density values, an assigned uncertainty for the density, the difference between the observed and smoothed density values and an index key to the source of the data. A complete list of references, identified by the index keys, appears at the end of the volume. 

Where appropriate, tables of smoothed, recommended values are given at integral multiples of 10 K over the experimental range of temperatures. Values at 293.15 K and 298.15 K are included when they are in the range of the original data set. The recommended values also have assigned uncertainties. 

Assigning uncertainties to experimental (or even theoretical [33]) results is a very important issue and deserves careful consideration. As already pointed out, this is not observed in many recent publications, hindering (to some extent) a reliable assessment of the data given there. If the accepted rules are followed, we may draw useful conclusions from the error bars. For instance, when the difference between two literature values for the enthalpy of the same reaction is larger than the sum of the respective uncertainties, it is likely that at least one of the results is affected by systematic errors. This is the case, for example, of two literature values for Ac//0[Fc(q5-C51 (5)2, cr], —5891.5 4.2 kj mol-1 and —5877.7 5.0 kJ mol-1 [31 ]. On the other hand, if the difference between a pair of values is smaller than the sum of the uncertainties, as in Af77°(LiOC2H5, cr), —477.1 4.0 kJ mol-1 and —473.1 2.5 kj mol-1 [25], we may conclude that systematic errors are probably absent in both results. 

Equilibrium constants for Eq. (6.13) with assigned uncertainties, corrected to 25°C where necessary. 

A superior measurement may show retrospectively that an earlier measured value with assigned uncertainty was in error [6]. The initial uncertainty may, for instance, have been under- or overestimated, or the earlier value - judged by the smaller uncertainty of the later measurement - may be found outside the initially estimated uncertainty range... 

Their partial pressure (J ) should be free of large error from Error does arise from uncertainties in the evaporation coefficients, ionization cross sections and total flux of species ( ). An extreme example of this error is the formation of o-AlgOg, which is biased by -9 kcal mol" if calculated from the reported ( ) pressures of Al and 0. Our assigned uncertainty includes contributions from this error and that of the Gibbs-energy function. 

The molecular structural parameters were obtained by LeBlanc et al (1 ) from combining the results of microwave measurements with those of electron diffraction determined by Jones et al. ( ).. Agreement within the assigned uncertainties was obtained by Stratton and Nielsen ( ) on the basis of infrared measurements. 

The AjH"(ZrF, g, 298.15 K) was evaluated as approximately 16 5 kcal mol" by Murad and Hlldenbrand (S), employing different A H (ZrFg) value. Their value is in agreement with the adopted one, within the assigned uncertainty. 

The assigned uncertainty ( 10 kcal mol ) is determined from the product 500xR which has been rounded to the The value of AjH (0 K) combined with JANAF data (3) for Mo(g) and 1(g) gives Dq°(Mo-I) -. ... 

The assigned uncertainty ( 2.0 kcal mol" ) is determined from the product lOOOxR which has been rounded to the nearest... 

The adopted value of a H at 298.15 K is that estimated by Brewer (1 ). The estimated value is consistent with the low volatility of solid molybdenum in iodine vapor reported by Schafer et al. (2). The estimated value given by Brewer (1 ) is A H (298.15 K)/R = 22000 5000 K. The assigned uncertainty ( 10 kcal mol" ) is determined from the product 5000xR which has been... 

Five data sources report values for the thermod)Tiamic quantity X. The reviewer has assigned uncertainties that represent the 95% confidence level as described in Section C.3. 

This value has the smallest assigned uncertainty among the various methods of determining a. 

Model results. The primary conclusion of the model is that Loihi and HIMU characteristics (for Sr, Pb, and He) can be generated from subducted components sequestered in two deep reservoirs. A nonlinear inversion was used to maximize the fit to the observations of continent concentrations and reservoir isotope ratios within the bounds of assigned uncertainties in the fluxes and fractionation coefficients. This was done using the U-Pb and Rb-Sr systems as well. In the best fit results, the D layer is 250-km thick (5% of the total mantle) and the RDM is 500-km thick. 

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