Dry ashing results in decreases in the apparent levels of Cu, Zn, and Fe in many types of plant tissue. The high concentrations of extraneous ions often present in plant ash solutions interfere with the determination of Fe, Mn, Zn, and Cu by atomic absorption. A procedure is proposed involving wet ashing with HNO3, HCIO4, and H2SO4 and complete extraction of the trace ele-ments with pyrrolidine dithiocarbamic acid in CHCI3. The CHCI3 is evaporated and the residue containing the trace elements is solubilized by refluxing with HNO3. Using the proposed procedure, good recovery of added trace elements was obtained and the relative standard deviation was below 2% for the four trace elements.

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In recent years there has been increasing concern about the identi…cation of parameters in dynamic stochastic general equilibrium (DSGE) models. Given the structure of DSGE models it may be di¢ cult to determine whether a parameter is identi…ed. For the researcher using Bayesian methods, a lack of identi…cation may not be evident since the posterior of a parameter of interest may di¤er from its prior even if the parameter is unidenti…ed. We show that this can be the case even if the priors assumed on the structural parameters are independent. We suggest two Bayesian identi…cation indicators that do not su¤er from this di¢ culty and are relatively easy to compute. The …rst applies to DSGE models where the parameters can be partitioned into those that are known to be identi…ed and the rest where it is not known whether they are identi…ed. In such cases the marginal posterior of an unidenti…ed parameter will equal the posterior expectation of the prior for that parameter conditional on the identi…ed parameters. The second indicator is more generally applicable and considers the rate at which the posterior precision gets updated as the sample size (T ) is increased. For identi…ed parameters the posterior precision rises with T , whilst for an unidenti…ed parameter its posterior precision may be updated but its rate of update will be slower than T . This result assumes that the identi…ed parameters are p T -consistent, but similar di¤erential rates of updates for identi…ed and unidenti…ed parameters can be established in the case of super consistent estimators. These results are illustrated by means of simple DSGE models.