Schematic representation of tracing the isotopic composition of source precipitation.
Coal can contain up to 200 mg kg−1As and coal ash can have a wide range of As contents (300 700 mg kg−1), depending on the composition of source coals (Wedepohl 1983).
However, Hansen et al. (2007), who analysed 40 samples taken from five cities in Denmark throughout one year, only found significant seasonal variations in ash, sulphur and chloride content, and not in any of the other 13 variables investigated, indicating little seasonal variation in the composition of source-separated municipal biowaste.
Here, δa and δp are the isotope compositions of source air and plant material, respectively, relative to international standard Vienna-Pee Dee Belemnite87.
An alkali quality coefficient combining the amounts of main compositions of source materials and sodium oxide (Na2O) in sodium silicate is proposed to assess the properties of alkali activated mortars, based on the hydration mechanism of alkali-activated pastes.
Source profiles for wood combustion and paved road dust were modified as appropriate for the local composition of these sources (Zheng et al. 2002).
This includes characterizing the magnitude, physical characteristics, and chemcial composition of pollutant sources and reactive chemcial precursors to secondary air pollution (i.e. ozone and secondary organic aerosol).
After appropriate corrections for the collisions of GCRs with interstellar gas, it is found that the inferred composition of the sources is similar to that of general solar-system matter; however, too little hydrogen and helium are present, and significant differences exist for isotopes of neon and iron.
Thus, if phosphate demand is low relative to input and is not heavily cycled within the ecosystem, the δ18O of phosphate will reflect the isotopic composition of phosphate sources to the system.
