ZIB

Hits per page

hits 1 - 2 | 2 hits

Sorting

Electronic Resource

Response of sorption processes of MCPA to the amount and origin of organic matter in a long-term field experiment (2001)

Haberhauer, G. ; Pfeiffer, L. ; Gerzabek, M. H. ; [et al.]

Oxford, UK : Blackwell Science Ltd

European journal of soil science 52 (2001), S. 0

add to mindlist on the mindlist

Details

ISSN: 1365-2389

Source: Blackwell Publishing Journal Backfiles 1879-2005

Topics: Geosciences , Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition

Notes: Changes in farming practices over long times can affect the sorption behaviour of MCPA ((4-chloro-2-methylphenoxy)acetic acid). We studied the adsorption–desorption mechanisms of MCPA on soil with varied amounts and origins of soil organic matter obtained from a long-term field experiment with various organic amendments. The origin of the soil organic matter seems to be crucial for the sorption behaviour of MCPA. Samples of soil amended with sewage sludge sorbed MCPA more strongly than the soil under any other treatment. Peat-amended soil was second followed by soil receiving animal manure, green manure, mineral fertilizer without N and the fallowed soil. Both the carbon content and the origin of the organic matter are important for the sorption. A decrease of carbon content of a soil does not necessarily imply a reduction of sorption capacity for polar organic acids such as MCPA. Nevertheless, our adsorption–desorption experiments suggest that with decreasing carbon content the role of mineral sorption mechanisms could become more pronounced. Our results showed that interactions of soil organic matter and soil minerals distinctly influence adsorption properties for MCPA.

Type of Medium: Electronic Resource

URL: http://dx.doi.org/10.1046/j.1365-2389.2001.00382.x

Permalink

Library	Location	Call Number	Volume/Issue/Year	Availability

Others were also interested in ...

Paper (German National Licenses)

Fulltext

Electronic Resource

Pathways, pathway tubes, pathway docking, and propagators in electron transfer proteins (1995)

Curry, W. B. ; Grabe, M. D. ; Kurnikov, I. V. ; [et al.]

Springer

Journal of bioenergetics and biomembranes 27 (1995), S. 285-293

add to mindlist on the mindlist

Details

ISSN: 1573-6881

Keywords: Tunneling pathways ; protein electron transfer ; donor-acceptor interactions

Source: Springer Online Journal Archives 1860-2000

Topics: Biology , Chemistry and Pharmacology , Physics

Notes: Abstract The simplest views of long-range electron transfer utilize flat one-dimensional barrier tunneling models, neglecting structural details of the protein medium. The pathway model of protein electron transfer reintroduces structure by distinguishing between covalent bonds, hydrogen bonds, and van der Waals contacts. These three kinds of interactions in a tunneling pathway each have distinctive decay factors associated with them. The distribution and arrangement of these bonded and nonbonded contacts in a folded protein varies tremendously between structures, adding a richness to the tunneling problem that is absent in simpler views. We review the pathway model and the predictions that it makes for protein electron transfer rates in small proteins, docked proteins, and the photosynthetic reactions center. We also review the formulation of the protein electron transfer problem as an effective two-level system. New multi-pathway approaches and improved electronic Hamiltonians are described briefly as well.