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Bioaccumulation Factors (BAFs) and Biota to Sediment Accumulation Factors (BSAFs) for PCBs in pike and eels 全文
1997
Harrad, Stuart J. | Smith, David J. T.
“Freely-dissolved” aqueous concentrations of 9 trichlorothrough heptachlorobiphenyls are reported, alongside those in sediments and fish from the R. Severn. For most congeners, BSAFs and lipid-normalised BAFs for pike exceed those for eels. Whilst R. Severn BSAFs are comparable with those for L. Ontario trout and New Bedford Harbour flounder, R. Severn BAFs are 1–2 orders of magnitude lower. This discrepancy may be due to inter-species variability, as well as inter-laboratory differences between operational definitions of “freely-dissolved” aqueous PCB, underlining that the same operational definition must be employed if R. Severn BAFs are extrapolated elsewhere. For eels, correlation of Log Kᵒʷ with Log BAF is better (R² = 0.66) than with BSAF (R² = 0.13), whilst similar correlation coefficients (R² = 0.81 and 0.82) were observed for pike. When Log Kᵒʷ is plotted against BSAF and Log BAF for both species combined, better correlation is observed for Log BAF (R² = 0.65), than BSAF (R² = 0.36). For both species combined, the observed relationship between Log BAF and Log Kᵒʷ for trichloro-through heptachlorobiphenyls is: Log BAF = 0.96 * Log Kᵒʷ −0.24.
显示更多 [+] 显示较少 [-]Bleached kraft pulp mill discharged organic matter in recipient lake sediment : Environmental and molecular properties 全文
1997
Saski, Eija K. | Mikkola, Raimo | Kukkonen, Jussi V. K. | Salkinoja-Salonen, Mirja S.
Environmental properties of organic matter contained halogen and sulfur were studied in sediments of bleached kraft pulp mill effluent (BKME) recipient lakes and 2 m³ outdoor enclosures (mesocosms). The BKME contributed to 1% (v/v) of the total water flow in the lake downstream of the pulp mill where the sediments contained 1.7 to 4 mg of tetrahydrofuran extractable organic halogen (EOX-Cl) and 0.6 to 0.8 mg of tetrahydrofuran extractable organic sulfur (EOS-S) g⁻¹ of organic matter. Upstream sediment contained 0.03 mg of EOXCl and 0.7 mg of EOS-S g⁻¹ of organic matter. EOX was a better indicator for the influence of BKME in the recipient sediment than EOS. The polarity of BKME contained EOX corresponded to log Kᵒʷ of < 1, and that of the downstream sediment contained EOX to > 4.5. HP-SEC analysis of the molecular weight distribution (MWD) of the EOX showed a peak between 300 to 600 g mol⁻¹ for the BKME and between 1000 to 2000 g mol⁻¹ for the downstream sediment. The MWD of the BKME contained EOS peaked at 300 to 1000 g mol⁻¹, and that of the downstream sediment contained EOS at 1000 to 5000 g mol⁻¹. These results indicate that BKME contained organic halogen and sulfur undergo major structural transformations when incorporated into sediment. The biota-to-sediment accumulation factor (BSAF) of EOX from sediments formed downstream of the mill and in the mesocosms to the lipids ofLumbriculus variegatus was 0.4 to 0.7. This is of a similar order of magnitude to the BSAF reported for 2,3,7,8-tetrachlorodibenzop-dioxin and 2,3,7,8-tetrachlorodibenzofuran.
显示更多 [+] 显示较少 [-]Pollution prevention in the paints and coatings industry
1997
Joseph, Ron
Analyzing nonpoint source water pollution problems
1997
Favero, Philip
Water pollution IV
1997
Rajar, R (Rudi) | Brebbia, C. A.
Himalayan microbial diversity
1997
Sati, S. C. | Saxena, J. (Jitendra) | Dubey, R. C.
The description, assessment and meaning of vertical fluxes of matter within ecotypes - a systematic consideration 全文
1997
Dämmgen, Ulrich | Grünhage, Ludger | Jäger, Hans-Jürgen
The interactions between sediments and water
1997
Evans, R. Douglas | Wisniewski, Joe | Wisniewski, Jan R.
Direct aqueous derivation and gas chromatographic analysis of halogenated lower carboxylates in environmental samples
1997
Ozawa, H. (Nagano-ken. Research Inst. for Health and Pollution (Japan))
Analytical method for hydrophilic polar environmental pollutants was studied. Among these pollutants, the halogenated lower carboxylates were the target compounds of this investigation. A novel but simple derivatization method necessary for sample preparation for instrumental analysis was developed. The new derivatization method for the carboxylates is not a conventional chemical reaction in non-aqueous solvent following isolation from the environmental samples but rather, a direct aqueous reaction ; direct conversion of the carboxylates to amides using a carbodiimide in dilute aqueous solution. Halogenoanilines were selectively used with dicyclohexylcarbodiimide (DCC) under acidic conditions at room temperature to form the anilide derivatives. Moreover, this reaction proceeds while mixing the sample water, DCC, a halogenoaniline, and small volume of extracting solvent. Thus, for the first time, simultaneous derivatization of the carboxylates and extraction of the products into solvent was achieved. Based on the results, simple and practical determination methods by gas chromatography were developed for traces of these carboxylates in environmental samples and the proposed methods were applied to some real samples. Such analytical derivatization methods for carboxylates are useful and noteworthy because they can form C-N bonds in aqueous media under mild conditions with carbodiimides and N atoms of amino and other compounds.
显示更多 [+] 显示较少 [-]Contact treatment of secondary treated domestic waste water using charcoal bed
1997
Kohno, Y. (Nagano-ken. Research Inst. for Health and Pollution (Japan)) | Suzuki, T. | Yokokawa, T. | Terashima, T.