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142.
An ecophysiological experiment was conducted to examine the biochemical effects of acidified seawater containing elevated concentration of CO(2) (C(CO2) 0.08, 0.20, 0.50 and 1.00%) on the copepod Centropages tenuiremis. AchE, ATPase, SOD, GPx, GST, GSH level and GSH/GSSG ratio of the copepod were analyzed. The results showed that elevated C(CO2) and the duration of culture time significantly influenced several biochemical indices in C. tenuiremis (ATPase, GPx, GST, GSH and SOD). Furthermore, the principal component analysis results indicated that 72.32% of the overall variance was explained by the first three principal components (GPx, SOD and GSH). Changes in GPx and GSH levels may play a significant role in the antioxidant defense of copepods against seawater acidification. The long-term response of copepods to seawater acidification and the synergistic effects of acidification with other environmental factors, such as temperature, salinity and trace metal need further investigation. 相似文献
143.
Enhanced P, N and C removal from domestic wastewater using constructed wetland employing construction solid waste (CSW) as main substrate 总被引:2,自引:0,他引:2
Construction solid waste (CSW), an inescapable by-product of the construction and demolition process, was used as main substrate in a four-stage vertical subsurface flow constructed wetland system to improve phosphorus P removal from domestic wastewater. A 'tidal flow' operation was also employed in the treatment system. Under a hydraulic loading rate (HLR) of 0.76 m3/m2 d for 1st and 3rd stage and HLR of 0.04 m3/m2 d for 2nd and 4th stage of the constructed wetland system respectively and tidal flow operation strategy, average removal efficiencies of 99.4% for P, 95.4% for ammoniacal-nitrogen, 56.5% for total nitrogen and 84.5% for total chemical oxygen demand were achieved during the operation period. The CSW-based constructed wetland system presents excellent P removal performance. The adoption of tidal flow strategy creates the aerobic/anoxic condition intermittently in the treatment system. This can achieve better oxygen transfer and hence lead to more complete nitrification and organic matter removal and enhanced denitrification. Overall, the CSW-based tidal flow constructed wetland system holds great promise for enabling high rate removal of P, ammoniacal-nitrogen and organic matter from domestic wastewater, and transforms CSW from a waste into a useful material. 相似文献
144.
水利信息化是实现水利现代化的基础和重要标志。以水管理对象为基础,利用现代信息技术构造数字流域,集中管理流域内的水事问题,是实现流域现代化管理的有效途径。从数字流域体系架构、水管理对象构造及全息化描述、基础平台构建、业务系统的构件化开发、数字功能流域等方面详细介绍了基于水管理对象的数字流域构造技术方法。 相似文献
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河源若想抓住"双转移"这个契机加速发展,就势必要结合河源的产业发展现状及资源状况,选择有优势的产业重点培育,发展壮大一些龙头企业,进而带动中小企业的发展,提高区域竞争力。区域竞争力的不断增强,也势必会促进更多、更优秀的企业来河源发展。同时,集群内企业也要充分利用这一机遇,利用企业内外资源,加快提升自身的竞争力。 相似文献
149.
针对水火电联合运行的电力系统,首次利用优化的方法分析水电和火电间的相互作用规律和负荷的空间分布特性对电力系统节能运行的影响规律,揭示了其联合运行时的水电和火电的运行特征.以此为基础,构建了可充分发挥梯级水电站互动特性的优化调度模型.以一个含有梯级水电站的水火电力系统为例进行分析,结果表明可通过充分发挥水电能源的互补作用,实现非可再生能源的节约和促进能源的可持续高效利用. 相似文献
150.
Microwave permeability spectra of single Co nanotube under equilibrium state have been studied by micromagnetics simulation.More than four obvious resonance peaks have been found(11.72,24.20,33.18 and 39.55 GHz).Such large resonance frequency cannot be found in other traditional magnetic materials.The configurations of magnetic moments along the nanotube have been simulated.The results show that the top end of nanotube has a"flow-out"pattern of magnetic moments configuration.The bottom end has a"flow-in"pattern of magnetic moments configuration.The magnetic moments within the main body of nanotube are aligned perfectly along the length of nanotube.The magnitude of natural resonance peak is strongly related to the volume fraction of a zone,which has the same orientation of magnetic moments.Large microwave permeability values have been found for single nanotube.The generalized Snoek’s law has been used to validate the micromagnetics simulations in this paper. 相似文献