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71.
海上风电产业是全球最具战略性和先导性的新兴产业之一。为促进山东省海上风电产业的高质量发展,文章基于调研梳理山东省海上风电产业发展现状,分析其中存在的问题,并提出对策建议。研究结果表明:山东省海上风能资源丰富,海上风电产业发展初显成效,但在产业发展规划、科技支撑能力、电力消纳能力、配套服务产业以及企业投资和生产意愿等方面存在不足;未来应遵循“统筹布局、创新技术、拓展方式、搭建平台、计划+示范”的发展思路,稳步推进山东省海上风电产业发展进程。 相似文献
72.
The dynamics of sediment‐associated contaminants over a transition from drought to multiple flood events in a lowland UK catchment 下载免费PDF全文
Fine sediment in suspended form, recently deposited overbank and in temporary storage on or in channel beds, was collected in the Nene basin during a period of drought through to a period of four high flows. The sediment was analysed for arsenic, copper, lead, phosphorus and zinc concentrations with the aim of investigating their sources, movement, temporary storage and potential for environmental harm. Copper, lead and zinc probably originated from urban street dusts, phosphorus (originally in dissolved form) from sewage effluent and arsenic from natural soils developed over ironstone. There was little difference in the metal or arsenic concentrations in the sediment under different flow conditions; instead, proximity to pollutant sources appeared to control their concentrations. Phosphorus in tributary sub‐catchments probably adsorbed to sediment during periods of low flow but these sediments were flushed away during high flows and replaced by sediment with lower concentrations. However, concentrations of all pollutants in overbank sediments along the Nene's main channel were not reduced in successive flood events, suggesting no first flush effect. Only phosphorus accumulated on sediment at concentrations exceeding those of its catchment‐based sources (e.g. street dusts, channel banks and catchment soils). This scavenging of aqueous phosphate by sediment explained the difference in behaviour between phosphorus, arsenic and heavy metals. The surface area and organic matter content were shown to have a small effect on contaminant concentrations. Street dust contaminants only exceeded predicted effect levels in close proximity to urban areas, suggesting a small potential for harm to the aquatic environment. Arsenic concentrations exceeded predicted effect levels in most sediment samples. However, it has been shown to be largely non‐bioavailable in previously published research on the Nene, limiting its potential for significant environmental harm. Phosphorus concentrations in river sediments are high in comparison to the soils in the catchment and in comparison with sediment–P concentrations in other published lowland catchment studies, indicating a large potential for eutrophication should the Phosphorus be, or become, bioavailable. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
73.
为了识别环境中有机污染物的来源和迁移转化,在线的单体稳定同位素分析(CSIA)是必不可少的关键技术,但是在实际应用中还存在问题.本文评价了目前已经开发的6种在线测定单体稳定同位素仪器的发展动态,包括气相色谱-同位素比值质谱计(GC-IRMS)、液相色谱-同位素比值质谱计(LC-IRMS)、直接引进-气相色谱-同位素比值质谱计(DI-GC-IRMS)、气相色谱-四极杆质谱计(GC-qMS)、气相色谱-多接收器电感耦合等离子体质谱计(GC-MC-ICPMS)、气相色谱-光强衰荡光谱仪(GC-CRDS).提出了在线测试中的5个值得注意的问题:①样品的预富集;②气相色谱(GC)和液相色谱(LC)分离;③多种仪器和多种方法选择使用;④有机化合物稳定同位素标准物质的开发;⑤安全保障.提出了三点建议:一是大力发展直接注入而不经过燃烧的有机污染物同位素测试技术,例如GC-qMS和GC-CRDS技术;二是继续开发研究GC-MC-ICPMS测定有机氯和有机溴同位素技术;三是快速研制有机化合物稳定同位素的国际标准物质.本文认为,在进行单体化合物同位素研究时应作多元素的同位素分析,而其最优的选择是采用直接样品注入而不经过燃烧的测试技术. 相似文献
74.
75.
太阳能在处理水、大气及土壤中有机污染物方面的应用 总被引:4,自引:0,他引:4
太阳能除作为传统的热源外,还可用于驱动化学过程。本文主要介绍利用光催化氧化技术处理废水、大气及土壤中有机污染物方面的最新进展,正在进行的现场实验、有关的太阳能设施,目前存在的主要困难及未来的应用前景等。 相似文献
76.
77.
A large number of nesting loggerhead sea turtles (n = 201) were sampled to establish the blood levels of 11 elements (Cu, Mn, Pb, Zn, Cd, Ni, Cr, As, Al, Hg, and Se). Almost all of the samples showed detectable levels of these 11 elements, and Zn and Se exhibited the highest concentrations (median values as high as 6.05 and 2.28 μg/g, respectively). The median concentrations of the most toxic compounds, As, Cd, Pb, and Hg, were relatively low (0.38, 0.24, 0.06, and 0.03 μg/g, respectively). We also determined the haematological and biochemical parameters in a subsample of 50 turtles to evaluate the potential effects of these contaminants on clinical parameters and found several associations. Our study reinforces the usefulness of blood for the monitoring of the levels of contaminating elements and their adverse effects on blood parameters in sea turtles. 相似文献
78.
为分析水流交汇区污染物输移扩散规律,开展了交汇区污染物浓度分布规律的实验和数值模拟研究。建立了交汇区污染物扩散的水气两相流数学模型,并采用实验结果进行验证,对交汇区不同流量、动量和交汇角情况进行实验和数值模拟研究。结果表明:含高浓度污染物的支流汇入干流后,在交汇口下游支流侧形成较长的污染带,且支流与干流的交汇角和流量比(动量比)越小,污染带越狭长;在污染带范围内,污染物浓度梯度较大;污染物分布主要受随流输移和扩散的综合作用影响,其中在交汇区污染物的扩散作用明显。 相似文献
79.
Differential presence of anthropogenic compounds dissolved in the marine waters of Puget Sound, WA and Barkley Sound, BC 总被引:1,自引:0,他引:1
Organic compounds were evaluated in March 2010 at 22 stations in Barkley Sound, Vancouver Island Canada and at 66 locations in Puget Sound. Of 37 compounds, 15 were xenobiotics, 8 were determined to have an anthropogenic imprint over natural sources, and 13 were presumed to be of natural or mixed origin. The three most frequently detected compounds were salicyclic acid, vanillin and thymol. The three most abundant compounds were diethylhexyl phthalate (DEHP), ethyl vanillin and benzaldehyde (∼600 ng L−1 on average). Concentrations of xenobiotics were 10-100 times higher in Puget Sound relative to Barkley Sound. Three compound couplets are used to illustrate the influence of human activity on marine waters; vanillin and ethyl vanillin, salicylic acid and acetylsalicylic acid, and cinnamaldehyde and cinnamic acid. Ratios indicate that anthropogenic activities are the predominant source of these chemicals in Puget Sound. 相似文献
80.
Gerardo?SeverinoEmail author Vladimir?Cvetkovic Antonio?Coppola 《Computational Geosciences》2005,9(4):155-177
We consider groundwater steady flow in a heterogeneous porous formation of random and stationary log-conductivity Y = ln K, characterized by the mean 〈Y〉, and the two point correlation function C
Y
which in turn has finite, and different horizontal and vertical integral scales I and I
v
, respectively. The fluid velocity V, driven by a given head drop applied at the boundary, has constant mean value U ≡ (U, 0, 0). Approximate explicit analytical expressions for transverse velocity covariances are derived. The adopted methodology
follows the approach developed by Dagan and Cvetkovic (Spatial moments of kinetically sorbing plume in a heterogeneous aquifers,
Water Resour. Res. 29 (1993) 4053) to obtain a similar result for the longitudinal velocity covariance. Indeed, the approximate
covariances of transverse velocities are determined by requiring that they have the exact first order variances as well as
zero integral scale (G. Dagan, Flow and Transport in Porous Formations (Springer, 1989)) , and provide the exact asymptotic limits of the displacement covariance of the fluid particles obtained
by Russo (On the velocity covariance and transport modeling in heterogeneous anisotropic porous formations 1. Saturated flow,
Water Resour. Res., 31 (1995) 129). Comparisons with numerical results show that the proposed expressions compare quite well in the early time
regime, and for Ut/I >100. Since most of the applications, like assessing the effective mobility of contaminants or quantifying the potential
hazards of nuclear repositories, require predictions over higher times the proposed approximate expressions provide acceptable
results. The main advantage related to such expressions is that they allow obtaining closed analytical forms of spatial moments
pertaining to kinetically sorbing contaminant plumes avoiding the very heavy computational effort which is generally demanded.
For illustration purposes, we consider the movement of one contaminant species, and show how our approximate spatial moments
compare with the numerical simulations. 相似文献