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The self-consistent molar volumes, elastic properties and thermodynamic properties of β-(Mg0.87,Fe0.13)2SiO4 wadsleyite have been determined over a wide temperature and pressure range based on an iterative numerical approach and experimental data from the literature. The obtained molar volumes, adiabatic bulk modulus, and shear modulus generally agree with the available experimental and theoretical results. The thermodynamic properties of α-(Mg0.9,Fe0.1)2SiO4 were also reinvestigated. Comparisons on thermodynamic properties show that the thermal expansions, heat capacities, and entropies of both β-(Mg0.87,Fe0.13)2SiO4 and α-(Mg0.9,Fe0.1)2SiO4 exhibit negative and nonlinear behavior with increasing pressure. Besides, the pressure plays a more important role in thermodynamic properties of the α-(Mg0.9,Fe0.1)2SiO4 than that of the β-(Mg0.87,Fe0.13)2SiO4. Using the Clausius-Clapeyron equation combined with molar volumes and entropies of both compositions, the phase transition boundary of Fe-bearing olivine and wadsleyite is estimated. The calculated transition pressure shows a nonlinear relationship with increasing temperature, and the value is generally lower than the previous studies on Fe-free olivine and wadsleyite at the same temperature. On the basis of our phase relation, the temperature at the 410 km discontinuity is estimated as 1795 ± 70 K under anhydrous conditions. The results not only confirm the feasibility of the Clausius-Clapeyron equation in obtaining the solid-solid phase transition, but also suggest that the existence of Fe might decrease the transition pressure of olivine-wadsleyite, which would consequently cause a higher temperature at the 410 km discontinuity.

The chemical composition of the earthworm (Eisenia foetida), worm casts and worm body fluids was investigated and compared with common foods and animal feeds. Common nutrient analysis showed that Eisenia foetida meal has a high protein content in the range of 54.6 to 71.0% dry matter. Protein content and amino acid composition were close to that of fish meal and hen egg, and higher than that of cow milk powder and soybean meal. Casts of E. foetida had a protein content of 7.9% dry matter, which is similar to that of corn meal, and hence worm casts could be used for partial replacement of corn meal or wheat bran in animal diets. Worm body fluids contained 9.4% protein and 78.79 free amino acid per litre and were found to be rich in vitamins and minerals, particularly iron (Fe). Our nutrient analyses suggest that earthworm (Eisenia foetida) could be an excellent source of protein to supplement animal feed and human food.

Zhang, Yufeng, Zhang, Donghui, Xu, Yongli, Zhang, Guishu, Sun, Zhenjun (2012): Effects of fragmentation on genetic variation in populations of the terrestrial earthworm Drawida japonica Michaelsen, 1892 (Oligochaeta, Moniligastridae) in Shandong and Liaodong peninsulas, China. Journal of Natural History 46 (21-22): 1387-1405, DOI: 10.1080/00222933.2012.659769, URL: http://dx.doi.org/10.1080/00222933.2012.659769