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91.
Zygmunt Usydus Joanna Szlinder-Richert Lucyna Polak-Juszczak Magorzata Malesa-Ciewierz Zbigniew Dobrzaski 《Chemosphere》2009,74(11):1495-1501
The results of tests for the purification of fish oils with activated carbon for industrial use are presented. The optimum parameters for the process of purification (granulation of the activated carbon, its dosage, the oil temperature, and the duration of mixing the oil with activated carbon) were previously established for the laboratory scale. The optimization of the process consisted of selecting purification parameters that would allow for maximum reduction of the toxic polychlorinated dibenzo-para-dioxins and polychlorinated dibenzofurans (PCDD/Fs) content, while retaining the favorable high fatty acid content [C20:5 n−3, eicosapentaenoic acid (EPA) and C22:6 n−3, docosahexaenoic acid (DHA)]. The use of that optimum parameters in industrial conditions confirmed the satisfactory results obtained in laboratory tests. Five types of oil derived from various Baltic fish were purified. Reduction in the PCDD/Fs content was 77.0–93.6% on average, whereas in the dioxin-like polychlorinated biphenyls (dl-PCBs)—it was 42.7–50.5% on average, with insignificant changes in the total amount of EPA and DHA content. Furthermore, a significant reduction in the content of arsenic was noted (by about 62% on average), with insignificant changes in the content of organochlorine pesticides (OCPs), and marker polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), cadmium, lead, and mercury.Purification provided fish oil having standardized parameters that allow for its use as feed additives, whilst retaining its favorable fatty acid content. 相似文献
92.
Levels of aromatic hydrocarbons in muscle or plaice and halibut were determined by fluorescence, using the chrysene standard, as recommended by the International Oceanographic Commision, for the analysis of PAH in environmental extracts. Concentrations were highest in muscle of halibut collected at the most contaminated, nearshore site, in the Saguenay Fjord of the St. Lawrence Estuary, compared to other locations further from shore. Although concentrations of fluorescing compounds were not statistically different in plaice, the saturated hydrocarbons displayed unquestionably more biodegradation, with a decrease of n-alkanes and increase of branched aliphatics, at the less contaminated site. Synchronous fluorescence indicated the presence of benzenoid and biphenyl hydrocarbons in the extracted mixtures, while GC-MS-TIC analysis tentatively identified the presence of a series of benzenoid (alkyl benzenes), chlorinated (PCB and DDE), N (trialkylamines) and O (phenols) hydrocarbons. These anthropogenic compounds could derive from petroleum products, surfactants and common products used in industry and households. This study emphasizes the importance of a multispectroscopic approach when investigating complex environmental mixtures. 相似文献
93.
Pipeline crossing construction alters river and stream channels, hence may have detrimental effects on aquatic ecosystems.
This review examines the effects of crossing construction on fish and fish habitat in rivers and streams, and recommends an
approach to monitoring and assessment of impacts associated with these activities. Pipeline crossing construction is shown
to not only compromise the integrity of the physical and chemical nature of fish habitat, but also to affect biological habitat
(e.g., benthic invertebrates and invertebrate drift), and fish behavior and physiology. Indicators of effect include: water
quality (total suspended solids TSS), physical habitat (substrate particle size, channel morphology), benthic invertebrate
community structure and drift (abundance, species composition, diversity, standing crop), and fish behavior and physiology
(hierarchy, feeding, respiration rate, loss of equilibrium, blood hematocrit and leukocrit levels, heart rate and stroke volume).
The Before-After-Control-Impact (BACI) approach, which is often applied in Environmental Effects Monitoring (EEM), is recommended
as a basis for impact assessment, as is consideration of site-specific sensitivities, assessment of significance, and cumulative
effects. 相似文献
94.
统计了112起建设工程事故,分析表明建设工程安全事故具有事故类型集中、承包商事故多发、检修及改造工程危险性较大、特殊作业管理不到位等特点和原因。提出了建设工程安全管理对策:开展安全文化建设,营造安全氛围;加强培训教育,提高参建人员尤其是施工操作人员的安全意识、技能水平;加大监管、惩戒力度,提高承包商违规成本;落实特殊作业各环节的管理。 相似文献
95.
Heavy Metal Concentrations in Water, Sediment, Fish and Some Benthic Organisms from Tigris River, Turkey 总被引:4,自引:0,他引:4
In this study concentrations of heavy metals, such as Cd, Co, Cu, Fe, Mn, Ni, Pb and Zn were determined in water, sediment,
muscle, liver and gill of fish (Silurus triostegus, Mastacembelus simack, Mystus halepensis, Orthrias euphraticus) the muscle and liver of crab (Potamon fluviatilis), the internal organs of fresh water snail (Physa acuta), and mussel (Unio elongatulus), and in whole biomass of green algae (Spirogyra sp.) examples collected seasonally from three selected sites (I, II, and III) of Tigris River and from a reference site on
Resan Creek. In general, the average Cd, Cu, Mn, Ni, Zn, and Fe values in Sites I, II, and III were found to be high in spring
and summer. The concentrations of heavy metals in the Tigris River are compared with previous studies in the same sites. The
results showed that Cu levels have gradually decreased during recent years. In Tigris River, among the living organisms, i.e.,
those which are living in benthic region and showing biomonitor characteristic, crab, snail, green algae, mussel and fish
are seen to be formed in sequence. Cu, Fe, Mn and Zn values obtained from the muscle of fish and from the mass of internal
organs of mussel and snail were found to be under the acceptable values suggested. 相似文献
96.
Fernandes C Fontaínhas-Fernandes A Cabral D Salgado MA 《Environmental monitoring and assessment》2008,136(1-3):267-275
Esmoriz–Paramos lagoon is an ecosystem of great ecological importance that is located on the northwest coast of Portugal and
has been degraded as a result of industrial and anthropogenic activities. Concentrations of heavy metals (Cr, Cu, Pb and Zn)
were measured in water, sediment and in tissues (liver and muscle) of Liza saliens, which is the dominant fish from the lagoon. Comparisons between metal concentrations in water and sediments were made with
those in tissues of fish caught at the lagoon. Metals in water were quantified predominantly bound to particulate and equalled
or exceeded the limit of chronic reference values. Metal concentrations in sediments varied among sampled sites. The relative
order of concentrations was “Zn > Cu ∼ Pb > Cr” the same pattern observed for metals in water. Metals in fish tissues showed
higher concentrations in liver (262 mg Cu·Kg−1 and 89 mg Zn·Kg−1) than in muscle (<3 mg Cu·Kg−1 and 26 mg Zn·Kg−1), while Pb and Cr were not detected. These results suggest that Cu and Zn are the metals of major concern in the lagoon.
Mullet detritivorous feeding habits, bioaccumulation pattern and the high sediment metals concentrations relative to the water
suggest that sediments can be the most important source of contamination in this ecosystem. The positive relationship found
between Cu in liver and fish length demonstrates that time of exposure is a crucial factor in bioaccumulation. Condition indices
(K and HSI) in mullets from the lagoon were higher compared to mullets from sea, suggesting abnormal condition in the lagoon
population. We conclude that metals chronic exposure in the lagoon can impose considerable fish stress. The results also show
that the lagoon is an area of environmental concern. 相似文献
97.
冯利华 《长江流域资源与环境》2002,(3)
结合 1998年长江流域的特大洪水 ,提出了洪水成因链的概念 ,分析了各个物理因子对江淮洪水的影响。指出影响江淮洪水的物理因子都是层层相接、环环相扣的 ,它们组成了一个互相联系、互为因果的洪水成因链。成因链上物理因子之间的正反馈作用和消长作用 ,导致成因链上各个因子的致洪理论都不能完全地自圆其说 ,因而也无法完全确定地用于洪水预测。只有深入探讨洪水成因链上物理因子之间的正反馈作用和消长作用 ,对它们进行全面综合的诊断分析 ,才能提高江淮洪水预测的准确率。 相似文献
98.
松花江干流洪水的发生有24年和3~4年变化周期.洪水出现有明显的阶段性,在上世纪可分为4段1911-1914;1930-1940;1954-1958;1984-1998年.随着时间的推移,洪水发生频次明显增加.分析得出,嫩江流域及第二松花江和拉林河流域7,8月的过量降水是造成洪水发生的直接原因.还分析了造成洪水的高空500hPa环流背景,7,8月西藏高原至北美阿拉斯加距平场分布为“ - -“流型,鄂霍次克海为阻塞高压,东北区为低压槽控制.在大水年春季,阿留申低槽加深,并向西延伸,乌拉尔高压形成并东移加强.1998年松嫩大水的发生基本符合上述规律和环流原因. 相似文献
99.
Pilot survey of a broad range of priority pollutants in sediment and fish from the Ebro river basin (NE Spain) 总被引:2,自引:0,他引:2
Lacorte S Raldúa D Martínez E Navarro A Diez S Bayona JM Barceló D 《Environmental pollution (Barking, Essex : 1987)》2006,140(3):471-482
Priority organic pollutants were investigated in sediments and fish collected along the Ebro river basin (NE Spain) to evaluate their occurrence, transport and bioavailability. Sediments were collected in 18 sites and two species of fish were captured in nine sites according to the availability in each area. The sampling sites covered industrial, urban and agricultural areas. Four methods were used to detect 20 organochlorine compounds (OCs), 8 polycyclic aromatic hydrocarbons, 3 organotin compounds, 2 alkylphenols and 40 polybrominated diphenyl ethers (PBDEs) from purified extracts. The contamination pattern was site specific and no downstream increase in concentration of pollutants was observed but rather a generalized low level diffuse pollution. Target compounds were detected in sediments at 0.01 to 2331 microg/kg dry weight, and only OCs and PBDEs were accumulated in benthopelagic fish. Toxicological assessment was performed according to predicted environmental levels and revealed sites where adverse effects could occur. 相似文献
100.
为探索适合我国的事故数据深度采集标准,并分析城市道路交通事故特征及致因,基于《道路交通事故深度调查信息采集表》(简称采集表),调查人员随交警赴事故现场随机详细调查87起城市道路交通事故。借鉴"Haddon Matrix"思想建立致因分析矩阵系统,分析事故的致因。发现采集表对事故地点、事故形态及原因项分类更加具体、明确,女性驾驶员的事故发生率略低于男性驾驶员,驾驶员年龄超过60岁后,发生事故的危险性显著提高,"交叉口影响区"事故50%由变更车道引起,非机动车驾驶员未戴安全头盔是造成严重伤害的重要原因。 相似文献