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991.
Tatsuo Suzuki 《Chemistry and Ecology》1995,10(3):249-258
A new material with high content of fly ash named 'Ashcrete' has been developed. to examine the applicability of Ashcrete to marine structures, strength characteristics, resistance to sea water attack, and safety in the marine environment have been studied. the following results have been obtained:
1) the strength characteristics of high-volume fly ash concrete depend upon the type and proportions of chemical activators as well as curing conditions.
2) Ashcrete using sodium chloride (NaCI) as a chemical activator shows high initial strength and good strength development with age.
3) Ashcrete containing NaCI activator shows good resistance to sea water from the viewpoint of its strength characteristics, volume changes and microstructurcs.
4) Since 1980 many types of large-scale artificial reefs made of Ashcrete have been installed in the sea. As a result of long-term studies and underwater observations, the Japanese Government has demonstrated the durability of the material, safety in the marine environment and attractiveness to fish.
5) It is therefore proposed that Ashcrete might be used in constructing large-scale sea mounts in deep water for the purpose of generating upwelling. 相似文献
1) the strength characteristics of high-volume fly ash concrete depend upon the type and proportions of chemical activators as well as curing conditions.
2) Ashcrete using sodium chloride (NaCI) as a chemical activator shows high initial strength and good strength development with age.
3) Ashcrete containing NaCI activator shows good resistance to sea water from the viewpoint of its strength characteristics, volume changes and microstructurcs.
4) Since 1980 many types of large-scale artificial reefs made of Ashcrete have been installed in the sea. As a result of long-term studies and underwater observations, the Japanese Government has demonstrated the durability of the material, safety in the marine environment and attractiveness to fish.
5) It is therefore proposed that Ashcrete might be used in constructing large-scale sea mounts in deep water for the purpose of generating upwelling. 相似文献
992.
灰色关联度模型在海洋产业分析中的应用——以辽宁省为例 总被引:4,自引:2,他引:2
辽宁省作为中国的海洋资源大省,在国内率先提出"海上辽宁"战略。阐述了辽宁省海洋经济的现状,以动态的分辨系数为基础,用灰色关联度模型对辽宁省的海洋产业特点进行了分析,进而针对辽宁省海洋产业结构应如何调整等问题提出了积极的对策和建议。 相似文献
993.
Toxicity testing of four heavy metals(Cd, Cu, Mn and As) using four species of tropicalmarine phytoplankton, Chaetoceros
calcitrans, Isochrysis galbana, Tetraselmis tetrahele and Tetraselmis sp., was carried out in multiwellplates with test volumes of 2 mL and the resultscompared to those of standard, large volume,shake-flasks. IC50 values (concentrations of metalsestimated to inhibit 50% growth relative to thecontrol) were determined after 96 hours based onautomated O.D. readings measured in Elisa microplatesby a Multiskan spectrophotometer. Good agreement wasachieved between O.D. readings and cell countsindicating that this new method is a simple,economical, practical and rapid technique for toxicitytesting, and provides good reproducibility of IC50 values. Results of the toxicity testsindicate that Cu was the most toxic metal (averageIC50 values ranging from 0.04 to 0.37 mg L-1), followed by Cd (0.06–5.7 mg L-1), Mn (7.2–21.4 mg L-1) and As (33.9–319.3 mg L-1).Test species had different degrees of sensitivity tothe metals tested, with I.galbana and C. calcitrans the mostsensitive to Cu, Cd and Mn. Based on these findingsit is recommended that the existing Malaysian InterimStandards for Marine Water Quality for Cd and Cu be reviewed. 相似文献
994.
Christ De Rooij Jean-Charles Boutonnet Christine Defourny Veronique Garny Andre Lecloux Roger Papp Roy S Thompson Dolf Van Wijk 《Environmental monitoring and assessment》1998,53(3):447-466
This risk assessment on 1,1,2-trichloroethane (T112) was carried out specifically for the marine environment, according to the methodology laid down in the EU risk assessment Regulation (1488/94) and the Guidance Document of the EU New and Existing Substances Regulation (TGD, 1997). The study consists of the collection and evaluation of data on effects and environmental concentrations from analytical monitoring programs in large rivers and estuaries in the North Sea area. The risk is indicated by the ratio of the "predicted environmental concentrations" (PEC) and the "predicted no effect concentrations" (PNEC) for the marine aquatic environment. In total, 22 studies for fish, 45 studies for invertebrates and 9 studies for algae have been evaluated. Both acute and chronic toxicity studies have been taken into account and the appropriate assessment factors have been used to define a PNEC value of 300 µg/l. Most of the available monitoring data apply to rivers and estuaries and were used to calculate PECs. The most recent data (1991-1995) support a typical PEC of 0.01 µg T112/l water and a worst case PEC of 5 µg T112/l water. The calculated PEC/PNEC ratios give a safety margin of 60 to 30,000 between the predicted no effect concentration and the exposure concentration. Additional evaluation of environmental fate and bioaccumulation characteristics showed that no concern is expected for food chain accumulation. 相似文献
995.
Christ De Rooij Jean-Charles Boutonnet Veronique Garny Andre Lecloux Roger Papp Roy S Thompson Dolf Van Wijk 《Environmental monitoring and assessment》1998,53(3):425-445
This risk assessment on 1,2-dichloroethane (EDC) was carried out specifically for the marine environment, according to the methodology laid down in the EU risk assessment Regulation (1488/94) and the Guidance Document of the EU New and Existing Substances Regulation (TGD, 1997). The study consists of the collection and evaluation of data on effects and environmental concentrations from analytical monitoring programs in large rivers and estuaries in the North Sea area. The risk is indicated by the ratio of the "predicted environmental concentrations" (PEC) and the "predicted no effect concentrations" (PNEC) for the marine aquatic environment. In total, 21 studies for fish, 17 studies for invertebrates and 7 studies for algae have been evaluated. Both acute and chronic toxicity studies have been taken into account and the appropriate assessment factors have been used to define a PNEC value of 1100 µg/l. Most of the available monitoring data apply to rivers and estuaries and were used to calculate PECs. The most recent data (1991-1995) support a typical PEC of 0.5 µg EDC/l and a worst case PEC of 6.4 µg EDC/l. The calculated PEC/PNEC ratios give a safety margin of 170 to 2200 between the predicted no effect concentration and the exposure concentration. Additional evaluation of environmental fate and bioaccumulation characteristics showed that no concern is expected for food chain accumulation. 相似文献
996.
Euro Chlor Risk Assessment for the Marine Environment Osparcom Region: North Sea - Chloroform 总被引:1,自引:0,他引:1
Sabine Zok Jean-Charles Boutonnet Christ De Rooij Veronique Garny Andre Lecloux Roger Papp Roy S Thompson Dolf van Wijk 《Environmental monitoring and assessment》1998,53(3):401-424
This risk assessment on chloroform was carried out specifically for the marine environment, according to the methodology laid down in the EU risk assessment Regulation (1488/94) and the Guidance Document of the EU New and Existing Substances Regulation (TGD, 1997). The study consists of the collection and evaluation of data on effects and environmental concentrations from analytical monitoring programs in large rivers and estuaries in the North Sea area. The risk is indicated by the ratio of the "predicted environmental concentrations" (PEC) and the "predicted no effect concentrations" (PNEC) for the marine aquatic environment. In total, 23 studies for fish, 17 studies for invertebrates and 10 studies for algae have been evaluated. Both acute and chronic toxicity studies have been taken into account and the appropriate assessment factors have been used to define a typical PNEC value of 72 µg/l. Due to limitations of the studies evaluated, a worst PNEC of 1 µg/l could also be used. Most of the available monitoring data apply to rivers and estuaries and were used to calculate PECs. The most recent data (1991-1995) support a typical PEC of 0.2 µg chloroform per litre of water and a worst case PEC of 5 to 11.5 µg chloroform per litre of water. The calculated PEC/PNEC ratios give a safety margin of 6 to 360 between the predicted no effect concentration and the exposure concentrations. A worst case ratio, however, points to a potential risk for sensitive species. Refinement of the assessment is necessary by looking for more data. Additional evaluation of environmental fate and bioaccumulation characteristics showed that no concern is expected for food chain accumulation. 相似文献
997.
Christ De Rooij Jean Charles Boutonnet Veronique Garny Andre Lecloux Roger Papp Roy S Thompson Dolf Van Wijk 《Environmental monitoring and assessment》1998,53(3):489-508
This risk assessment on tetrachloroethylene (PER) was carried out specifically for the marine environment, according to the methodology laid down in the EU risk assessment Regulation (1488/94) and the Guidance Document of the EU New and Existing Substances Regulation (TGD, 1997). The study consists of the collection and evaluation of data on effects and environmental concentrations from analytical monitoring programs in large rivers and estuaries in the North Sea area. The risk is indicated by the ratio of the "predicted environmental concentrations" (PEC) and the "predicted no effect concentrations" (PNEC) for the marine aquatic environment. In total, 18 studies for fish, 13 studies for invertebrates and 8 studies for algae have been evaluated. Both acute and chronic toxicity studies have been taken into account and the appropriate assessment factors have been used to define a PNEC value of 51 µg/l. Most of the available monitoring data apply to rivers and estuary waters and were used to calculate PECs. The most recent data (1991-1995) support a typical PEC of 0.2 µg PER/l water and a worst case PEC of 2.5 µg PER/l water. The calculated PEC/PNEC ratios give a safety margin of 20 to 250 between the predicted no effect concentration and the exposure concentration. Additional evaluation of environmental fate and bioaccumulation characteristics showed that no concern is expected for food chain accumulation. 相似文献
998.
Distribution of Heavy Metals in Surface Sediments from an Antarctic Marine Ecosystem 总被引:3,自引:0,他引:3
Andrade S Poblet A Scagliola M Vodopivez C Curtosi A Pucci A Marcovecchio J 《Environmental monitoring and assessment》2001,66(2):147-158
The concentrations of lead, cadmium, copper,chromium, iron, manganese and zinc in surfacesediments collected from Potter Cove, in the 25de Mayo Island (King George Island), Antarctica, andits drainage basin, were measured by atomic absorptionspectroscopy. The obtained results were use todetermine the areal and vertical distribution of themetals of in the Cove and potential sources of thesemetals to this environment. The geochemical datasuggest that most of the metals found in Potter Coveconstitute a redistribution of autochthonous materialswithin the ecosystem. Therefore, the metalconcentrations can be considered to be present atnatural background levels in surface sediments. 相似文献
999.
微生物技术处理饮食服务业含油污水的实验研究 总被引:2,自引:0,他引:2
通过3次采自乌鲁木齐市鸿春园饭店不同时期排放的污水,经培养筛选出的28株具有较强除油能力的菌种回接污水后,其平均除油率达68%,其优选菌种回接污水24h后的除油率达90%,而同批污水自然存放10d后的除油率仅为29%。采用选培优良菌种集中快速处理,可以显著提高此类污水的处理效率。 相似文献
1000.
发挥海南资源优势 开发建设“海洋大省” 总被引:2,自引:0,他引:2
作为我国最年青的省份--海南,虽然其陆域狭小,却是我国拥有海洋面积最大和唯一具有法定海域管辖权的省份,也是我国目前最大的经济特区。为加速海南外向型经济发展,本文在客观分析和综合比较海南热带作物、矿产、旅游和海洋等四大优势资源的基础上,提出以开发海洋资源,发展海洋产业,振兴海洋经济为内容的“海洋大省”开发战略整体构想,同时,并就“海洋大省”的建设目标、依据、重点和步骤等提出一些建设性意见。 相似文献