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171.
The rates of Sb(III) oxidation by O2 and H2O2 were determined in homogeneous aqueous solutions. Above pH 10, the oxidation reaction of Sb(III) with O2 was first order with respect to the Sb(III) concentration and inversely proportional to the H+ concentrations at a constant O2 content of 0.22 × 10−3 M. Pseudo-first-order rate coefficients, kobs, ranged from 3.5 × 10−8 s−1 to 2.5 × 10−6 s−1 at pH values between 10.9 and 12.9. The relationship between kobs and pH was:
172.
Summary results from a pilot study conducted around an oil production platform on the Northwest Shelf of Australia 总被引:3,自引:0,他引:3
King SC Johnson JE Haasch ML Ryan DA Ahokas JT Burns KA 《Marine pollution bulletin》2005,50(11):1163-1172
The Australian Institute of Marine Science (AIMS) conducted a pilot study around the Harriet A oil production platform on the Northwest Shelf of Australia. We evaluated hepatic ethoxyresorufin-O-deethylase (EROD) activity, fluorescent aromatic compounds (FACs) in bile and immunodetection of CYP1A-like proteins in two Australian tropical fish species, Gold-Spotted Trevally (Carangoides fulvoguttatus) and Bar-Cheeked Coral Trout (Plectropomus maculatus) to assess exposure to petroleum hydrocarbons associated with produced formation water (PFW). Additionally, the incidence of hydrocarbon-degrading bacteria isolated from the liver and bile of all fish captured was examined. Low EROD activity was found in both species, with EROD activity in C. fulvoguttatus showing significant site differences. FACs and CYP1A protein levels in C. fulvoguttatus showed a clear trend in hydrocarbon exposure consistent with hydrocarbon chemistry data: Harriet A>Harriet C>reference site. P. maculatus showed elevated levels of FACs at Harriet A as compared to the reference site and demonstrated detectable levels of CYP1A-like proteins at these two sites. Hydrocarbon-degrading bacteria were found in the liver and bile of both species, yet there was no correlation by sites. Our results demonstrate that C. fulvoguttatus and P. maculatus have potential as indicator species for assessing the effects from exposure to petroleum hydrocarbons. Both FACs and CYP1A are providing warning signs that there is potential for biological effects on fish populations exposed to PFW around the Harriet A production platform. 相似文献
173.
174.
A variational approach to whole-Earth dynamics 总被引:3,自引:0,他引:3
175.
We examine the effects of Io ejecta on the surface and environment of Europa. We find that the observed sulfur on the trailing side of Europa, when interpreted as a deposit in equilibrium between implanation of, and sputtering by, corotating Io ejecta, implies a slow loss of material from Europa by sputtering. From this we infer that the spectrum of particles sputtered from water ice is soft. The quantity of observed sulfur and its confinement to the trailing hemisphere appear to exclude significant implantation and sputtering by energetic heavy ions. We also conclude that the contribution from Europa to the magnetospheric plasma (even at Europa itself) is negligible compared to the matter ejected from Io. 相似文献
176.
177.
The residential preferences of Afro-American students in three black colleges in Pennsylvania, North Carolina, and Texas are factor analyzed to determine whether major differences exist. Mapping the factor scores for the students in each college reveals that state rankings vary markedly from one region to another, black spatial preferences differ markedly from those students attending predominately white universities, and preference patterns reflect contemporary interregional black migration trends. 相似文献
178.
A study was conducted on Cu, Zn, Cd, Fe, Co and Ni levels in Saanich Inlet anoxic seawater. Data on the concentration of these
trace metals and H2S, and other oceanographic parameters were obtained in four cruises.
Equilibrium models are presented together with in situ data. The results strongly support the assumption that the solubilities
of Cu, Zn, Cd, Fe, Co and Ni are controlled by bisulfide and/or polysulfide complexes. The species of Cu, Zn, Cd and Ni are
shown to be Cu(S4)
2
3−
and Cu(Sn4S5)3−, Zn(HS)
2
0
and ZnHS
2
−
, Cd(HS)
2
0
and Ni(HS)
2
0
, respectively. The solid species controlling Fe2+ and Co2+ are respectively the pyrohotites FeS and CoS. The data illustrates that thermodynamic equilibrium has been established in
the H2S-controlled seawater of Saanich Inlet, and that equilibrium has not been established in the H2S−O2-coexisted seawater of Saanich Inlet. The lack of equilibrium in the H2S−O2-coexisted seawater is a result of the flushing or mixing of oxygenated seawater with anoxic water. The new species of trace
metals are still in the processes of reduction and precipitation.
Contribution No. 1428 from Institute of Oceanology, Academia Sinica 相似文献
179.
180.
Economic and social development indicators suggest that the small West African state of Sierra Leone is among the poorest
countries in the world. Sierra Leone’s economy and quality of life deteriorated rapidly during a decade of political instability
and civil war in the 1990s, when many people fled their homes and abandoned their livelihoods due to the rebel insurgency.
This paper examines the post-war reconstruction scenario in Sierra Leone and presents recent evidence from two rural communities
in the Eastern Province that were badly affected by the conflict. The paper considers the links between the farming and diamond
mining sectors, which, despite severe dislocation during the conflict period, have proved to be remarkably resilient. It is
argued that seasonal labour mobility associated with this dual economy has not only continued to be a key ingredient in sustaining
livelihood portfolios, but is actually an essential pre-condition for the creation of an enabling environment for sustainable
post-conflict return.
相似文献
Tony BinnsEmail: |