metals used in everyday life are produced from ores occurring in the earth’s crust. geological processes are known to concentrate minerals to form ores of economic value. mineral processing engineers concentrate these ores by mechanical and physico-chemical methods while the extractive metallurgist extracts the metals by chemical means.

Statistical mechanics of relative species abundance (RSA) patterns in biological networks is presented. The theory is based on multispecies replicator dynamics equivalent to the LotkaVolterra equation, with diverse interspecies interactions. Various RSA patterns observed in nature are derived from a single parameter related to productivity or maturity of a community. The abundance distribution ...

One approach to the study of the structure of animal communities for which there is a considerable amount of raw data is the comparison of abundances of the species of a group of organisms in a given locality. The basic information is a list of species found and the abundance of each. This can best be plotted by ranking the species from commonest to rarest along the abscissa and plotting their ...

We present measurements of relative elemental abundances in plumes and interplumes. Plumes are bright, narrow structures in coronal holes that extend along open magnetic field lines far out into the corona. Previous work has found that in some coronal structures the abundances of elements with a low first ionization potential (FIP) <10 eV are enhanced relative to their photospheric abundances. ...

A new method is presented for the reconstruction of the radiocarbon production rate from the measured relative abundance of ∆14C. The method treats the carbon cycle as a linear Fourier filter and thus allows for the correct and unambiguous inversion of the carbon cycle. The 14C production rate, as reconstructed by the Fourier filter method, agrees with the results obtained by the traditional it...