geoscience.net logo
+ Resolve Article
+ Follow Us
Follow on FacebookFollow on Facebook
Follow on TwitterFollow on Twitter

+ Translate
+ Subscribe to Site Feed
GeoScience Most Shared ContentMost Shared Content

Environmentally important, poorly crystalline Fe/ Mn hydrous oxides; ferrihydrite and a possibly new vernadite-like mineral from the Clark Fork River Superfund complex


, : Environmentally important, poorly crystalline Fe/ Mn hydrous oxides; ferrihydrite and a possibly new vernadite-like mineral from the Clark Fork River Superfund complex. American Mineralogist 90(4): 718-724

Ferrihydrite and a vernadite-like mineral, in samples collected from the riverbeds and floodplains of the river draining the largest mining-contaminated site in the United States (the Clark Fork River Superfund Complex), have been studied with transmission electron microscopy (TEM) and energy dispersive X-ray (EDX) analysis. These poorly crystalline minerals are environmentally important in this system because contaminant heavy metals (As, Cu, Pb, and/or Zn) are always associated with them. Both two- and six-line ferrihydrite have been identified with selected-area electron diffraction. For the vernadite-like mineral, the two d values observed are approximately between 0.1 and 0.2 Aa larger than those reported for vernadite, the Mn hydrous oxide that is thought to have a birnessite-like structure, but which is disordered in the layer stacking direction. In several field specimens, the ferrihydrite and vernadite-like minerals are intimately mixed on the nanoscale, but they also occur separately. It is suggested that the vernadite-like mineral, found separately, is produced biogenically by Mn-oxidizing bacteria, whereas the same mineral associated with ferrihydrite is produced abiotically via the heterogeneous oxidation of Mn (super 2+) (sub aq) initially on ferrihydrite surfaces. Evidence from this study demonstrates that the vernadite-like mineral sorbs considerably more toxic metals than does ferrihydrite, demonstrating that it may be a good candidate for application to heavy-metal sorption in permeable reactive barriers.

US$29.90


Other references

Pott, E., 2007: AIDS prevention in Germany. In 1987 the national AIDS prevention campaign "Gib AIDS keine Chance" (Don't give AIDS a chance) was started in Germany. After a very difficult and controversial political debate about a probably successful response to AIDS, in the...

Brown, M.B.; Bradbury, J.M.; Davis, J.K., 1996: ELISA in small animal hosts, rodents, and birds. Tully, J G [Author], Razin, S [Author] Molecular and diagnostic procedures in mycoplasmology, Vol 2 Diagnostic procedures 93-104

Camon, E.B.; Chaplin, P.J.; Howard, C.J.; Collins, R.A., 1997: Modulation of bovine T cell responses by IL-12 and the influence of IL-4 on interferon-gamma responses to respiratory syncytial virus. Biochemical Society Transactions 25(2): 291s-291s

Karelin, A.A.; Guseva, E.P.; Mardashev, S.R., 1971: Serum guanidine acetate-N-methyltransferase in patients with various diseases of the hepato-biliary-pancreatic system. Sovetskaia Meditsina 34(5): 18-23

Vardy, CR., 1995: A new genus and species of stridulating wasp from Costa Rica Hymenoptera Sphecidae, Gorytini. Entomofauna. 25 November; 1619: 393-398

Hopkins C.C.E.; Tande K.S.; Gronvik S.; Sargent J.R., 1984: Ecological investigations of the zooplankton community of balsfjorden northern norway an analysis of growth and overwintering tactics in relation to niche and environment in metridia longa calanus finmarchicus thysanoessa inermis and thysanoessa raschi. The copepods C. finmarchicus (Gunnerus) and M. longa (Lubbock) together with the euphausiids T. inermis (Kroyer) and T. raschi (M. Sars) are the dominant biomass of the zooplankton in Balsfjorden. Although they all spawn during the phytoplankton p...

Schepers, J.; Francis, D., 1977: Equilibrium and extraction patterns from suction cups. Agronomy abstracts: 9th) 137

Pushkar', L.N.; Troitskiĭ, V.B.; Liaĭman, O.M.; Minina, L.T., 1980: Therapeutic properties of a new drug form of rheopolyglucin. Problemy Gematologii i Perelivaniia Krovi 25(12): 35-38

Green, S.S.; Comer, L.; Elliott, L.; Neubrander, J., 2011: Exploring the value of an international service-learning experience in Honduras. The purpose of this study was to determine the effect of an international service-learning experience in Honduras on the cultural competence of the participants. The study included a quantitative portion in which participants utilized the Cultural...

Befort, C.A.; Klemp, J., 2012: Sequelae of breast cancer and the influence of menopausal status at diagnosis among rural breast cancer survivors. Rural women are among the largest medically underserved groups in the nation, yet few studies have evaluated the sequelae of breast cancer in this population. The purpose of this study was to examine the physical and psychosocial effects of breast...