Are All Creatures Created Equal? (Chemistry of biosphere)
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Are All Creatures Created Equal?(Chemistry of biosphere)
Yuan-Hui (Telu) Li
Department of Oceanography
University of Hawaii at Manoa
Outline
• Chemical compositions of terrestrial and marine organisms
• Biophile and biophobe elements• Surface complexation model• Human beings as a part of nature• Fossil carbon: black shale, coal and crude oil• Conclusions• Acknowledgment
Data by Bowen (1979)
Biological standard reference materials (SRM)
Biophile: major ions in seawater, and B-type cations (d-shell electrons 5-10; high polarizability).
Biophobe: A-type cations (electron configurations of noble gases; low polarizability).
Wackett et al. (2004)
Hydration of metal oxide surface: O O O O O O Si Si Si Si SiO O O O O O + n H2O Si Si Si Si Si H H H H O O O O O O O O Si Si Si Si SiO O O O O O Si Si Si Si Si
Surface complexation model:Amphoteric property of oxide and organic matter surfaces:For Cations M+z :
M+z + MeOH MeO‑M+z‑1 + H+
Me are mostly Si, Fe, and Mn
K = {MeO‑M+z‑1 }[H+ ]/[M+z ]{MeOH }
= Kd [H+]/{MeOH }
M+z + R-LH R-L‑M+z‑1 + H+
L are organic ligands with hydrophilic functional groups, such as R-OH, R-NH2, and R-SH, on the surface of organic particles.The relative O-M and L-M bond strengths for various cations are shown to be proportional to K, Kd, and the electron bonding energy to gaseous ions (Iz), i.e.
M+z (g) + e- M+z-1 (g) + Iz
A (g) + e- A-1 (g) + I-1
For anions Az (e.g. Cl-, HS-; SO4-2, MoO4
-2, ReO4-)
Az + MeOH Me-A-z+1 + OH
Az + R-OH R-A-z+1 + OH
The relative Me-A and R-A bond strengths are proportional to
the I-1 of simple anions, or inversely related to the Iz of the
central cation of oxyanion.
Me-Cl R-Cl
O O Me-O-S-O R-O-S-O
O O
M+z + L-4 ML+z-4
= [ML+z-4]/([M+z ][L-4]
Mean residence time =
urine
mam
urine
man
C
X
CF
XM50
-0.5
0.0
0.5
1.0
F2
-0.5
0.0
0.5
1.0
F4
-8
-6
-4
-2
0
2
F2
scor
e
-2
0
2
4
F4
scor
e
-1.0 -0.5 0.0 0.5 1.0F1
-1.0 -0.5 0.0 0.5 1.0F3
-3 -2 -1 0 1 2 3F1 score
-2 -1 0 1 2 3 4 5F3 score
UZr
K
Al
Ca
Cu
NiOC
Zn
Ba
Mo
ICRb Y
(a) (b)
(c) (d)
Co
SrSi
Ti V
Sr
U
P
Cretaceousblack shale
Mg
S
AsFe
CaIC
Mn
OC rich S rich
OC rich S rich
0
10
20
30
40
OC
(%
)
0
100
200
300
400
500
Mo
(ppm
)
0
2
4
6
8
10
12
CaO
(%
)
0
10
20
30
40
OC
(%
)0
10
20
30
ex F
e2O
3 (%
)0
10
20
30
Fe2
O3
(%)
40 50 60 70Depth (cm)
0 10 20 30 40OC (%)
0.00 0.01 0.02 0.03 0.04 0.05MnO (%)
0 5 10 15 20 25S (%)
0 5 10 15 20 25S (%)
5 10 15Al2O3 (%)
(a)
(e) (f)
(b)
(d)(c)
pyrite
Black shale OC-rich S-rich
shale
Conclusions1. The relative abundances of elements in marine and terrestrial living organisms, including human being, are remarkably similar.2. Enrichment of biophile elements relative to soil or pelagic clays mainly reflect the formation of extra strong bonds between highly polarizable biophile elements and organic ligands containing -NH2, -SH, and -COOH groups.3. The mean residence times of elements in the human body again can be explained by the concept of the relative bond strength between ions and organic matter.4. The enriched biophile elements in coals are mainly associated with sulfide phases.5. The enriched biophile elements in crude oils are mainly concentrated in the resin and asphaltene fractions.
Acknowledgement: Many thanks are due to Professor Yoshiki Sohrin, who has graciously sponsored my visit at the Kyoto University. The pioneering works by Professor Toshio Yamamoto on seaweeds are acknowledged here.
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