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931.
Dominika Saniewsk Magdalena Beldowsk Jacek Beldowski Micha? Saniewski Justyna Kwa′sniak Lucyna Falkowska 《环境科学学报(英文版)》2010,22(8):1144-1150
The aim of this study was to characterize mercury (Hg) contamination in the coastal waters of the Southern Baltic Sea, and to
investigate transformations of Hg in the initial links of the marine food chain. Concentrations of Hg in water, particulate matter,
plankton and macrophytes at various stations in the coastal zone (a bay with restricted water exchange, near an industrial city, river
mouths, and the open sea) were measured in 2006–2008. Hg concentrations observed in the Southern Baltic varied greatly, showing
the highest average values in all environmental compartments near the river mouths. In shallow, sheltered parts of the gulf, where water
exchange is restricted, Hg concentrations in the water and in macrophytes were elevated relative to those in the coastal zone of the
deeper part of the bay and in the open Baltic. Distance to the river mouth, terrestrial runo , and quantity and quality of organic matter
were more important than seasonal variations in controlling Hg and HgSPM concentrations in water samples. Mercury concentrations in
the surface microlayer at the air/sea interface were over 10 times higher than those in the bulk surface water. Concentrations of Hg in
macrophytes in the winter were significantly higher than those in the warm seasons (spring, summer, autumn). This was probably the
combined e ect of higher availability of Hg in porewaters and leaf growth inhibition. 相似文献
932.
933.
为了解决评价因素间的不确定性和不相容性问题,采用一种新方法对旅游环境承载力进行综合评价,该方法称为物元分析法。通过建立旅游环境承载力评价标准体系和物元模型来确定一个旅游区的环境承载力状态。以安徽省旅游区为例进行评价,结果表明该方法简单可行。对旅游规划决策和区域旅游业的可持续发展有重要的意义。 相似文献
934.
澳门夏季大气颗粒物单颗粒微观形貌分析 总被引:7,自引:0,他引:7
应用高分辨率场发射扫描电镜(FESEM)和图像分析技术,研究了澳门地区夏季(2007年7月)大气可吸入颗粒物的形貌特征以及不同种类颗粒物的数量-粒度和等效体积-粒度分布.结果表明,澳门可吸入颗粒物中,烟尘集合体和矿物颗粒普遍存在;矿物颗粒为不规则状,烟尘集合体有链状、蓬松状等形态;烟尘集合体在数量上平均分别约占30%~40%,矿物颗粒在数量上平均分别约占20%,烟尘集合体颗粒较多说明澳门夏季受机动车尾气影响较重.澳门大气PM10的等效粒径主要分布在0.2~0.4 μm范围内,主要为较细粒子.颗粒物种类有明显的地点差异,交通繁忙的高士德马路路口以烟尘集合体居多(平均47%),且其粒径在较宽范围内都有分布(0.1~0.8 μm);隧道内亦以烟尘集合体的比例较大,可高达59%;货运码头采样点以矿物颗粒较多. 相似文献
935.
不同性质污泥在模拟填埋场中的稳定化进程研究 总被引:4,自引:1,他引:3
为确定污泥达到稳定化所需的时间,研究了污泥及改性污泥在填埋后的稳定化进程.结果显示,经过498d的降解,生物污泥、生物污泥+矿化垃圾和化学污泥中有机质的降解率分别为67.1%、61.6%和30.5%.污泥初始有机质含量越高,总降解率越高.生物污泥较化学污泥易于降解.按照污泥中的有机质降到100mg·g-1预测,污泥填埋场达到稳定化所需时间约为3年;按照生物可降解物质(BDM)降到4.76%为污泥达到完全稳定状态预测,污泥填埋场达到稳定化所需时间是2.9~4.7年.从上海老港污泥填埋场多年的实际运行情况来看,污泥填埋场在封场3年后即可达到稳定化,所形成的矿化污泥即可开采和利用. 相似文献
936.
Impacts of soil organic matter, pH and exogenous copper on sorption behavior
of norfloxacin in three soils 总被引:3,自引:0,他引:3
ZHANG Jie LI Zhaojun GE Gaofei SUN Wanchun LIANG Yongchao WU Laosheng 《环境科学学报(英文版)》2009,21(5):632-640
Norfloxacin (Nor) sorption and the factors (soil organic matter (SOM), pH, and exogenous copper (Cu) influencing the sorption were investigated in a black soil (soil B), a fluvo-aquic soil (soil F), and a red soil (soil R). With increasing of Nor concentrations, sorption amount of norfloxacin increased in both the bulk soils and their SOM-removed soils, but the sorption capacity in SOM-removed soils was higher than that of their corresponding bulk soils, indicating that the process of norfloxacin sorption in soil was influenced by the soil properties including SOM. The sorption data in all bulk soils and SOM-removed soils were fitted to Freundlich and Langmuir models. The correlation coefficients suggested that the experimental data fitted better to Freundlich equation than to Langmuir equation. Furthermore, the data from soil F and SOM-removed F could not be described by Langmuir equation. The norfloxacin sorption amount decreased in soil B and soil F, whereas it increased in soil R as solution pH increased. The maximum KD and KOC were achieved in soil R when the equilibrium solution pH was 6. And the norfloxacin sorption was also influenced by the exogenous Cu2+ ions, which depended on the soil types and Cu2+ concentrations. With increasing of Cu2+ concentrations in solution, generally, sorption amount, KD and KOC for norfloxacin in soils increased and were up to a peak at 100 mg/L Cu2+, and then the sorption amount decreased regardless of norfloxacin levels. 相似文献
937.
用浓硝酸和高氯酸混酸体系在超声波作用下消解滤膜,加入稳定剂琼脂,用超声波震荡15min制成悬浮液,用火焰原子吸收光谱法测定TSP中的锌、铅和铁的含量,并以传统浓HNO3-H2O2湿法消解-原子吸收光谱法的测定结果为参考对测定值进行t检验,结果表明:RSD≤3.27%(n=6),两种方法的相对误差<±0.85%,且两种方法无显著性差异,说明悬浮液进样法的测定结果准确、可靠。 相似文献
938.
采用批处理方法,评价几种典型的环境有机质对缺氧或无氧FeS-水体系中,林丹非生物脱氯转化动力学的影响.测定了不同反应介质条件下,林丹的非生物脱氯转化速率和产物的分布.结果表明,反应体系中高浓度的表面活性剂对林丹的转化有明显的抑制作用,转化速率为对照体系的18%;萘醌对林丹转化的速率及其产物分布均没有明显的影响;加入25 mg/L胡敏酸可使林丹的转化速率提高1.29倍;加入2 mmol/L 2,2'-联吡啶明使林丹的转化速率提高2.2倍.研究表明,水生态环境中与FeS共存的有机物可能对有机氯污染物的自然衰减产生较大影响. 相似文献
939.
Cosmic vacuum energy decay and creation of cosmic matter 总被引:1,自引:0,他引:1
In the more recent literature on cosmological evolutions of the universe, the cosmic vacuum energy has become a nonrenouncable
ingredient. The cosmological constant Λ, first invented by Einstein, but later also rejected by him, presently experiences an astonishing revival. Interestingly
enough, it acts like a constant vacuum energy density would also do. Namely, it has an accelerating action on cosmic dynamics,
without which, as it appears, presently obtained cosmological data cannot be conciliated with theory. As we are going to show
in this review, however, the concept of a constant vacuum energy density is unsatisfactory for very basic reasons because
it would claim for a physical reality that acts upon spacetime and matter dynamics without itself being acted upon by spacetime
or matter. 相似文献
940.
在实验室通过模拟土壤柱研究了人工地下水回灌过程中溶解性有机物的去除及其三卤甲烷生成势和三卤甲烷生成活性的变化.利用XAD树脂将回灌水中的溶解性有机物分为3个部分:疏水性有机酸、过渡亲水性有机酸和亲水性有机物.疏水性有机酸的三卤甲烷生成活性高于过渡亲水性有机酸和亲水性有机物.土壤含水层处理(SAT)对亲水性有机物的去除率为68.51%,对疏水性有机酸和过渡亲水性有机酸的去除率分别为58.64%和41.86%.经SAT系统处理后,溶解性有机物及各有机组分的三卤甲烷生成势减少,而三卤甲烷生成活性升高.疏水性有机酸是生成三卤甲烷的主要有机组分.亲水性有机物在SAT系统进水中的三卤甲烷生成活性较低,但由于含量高,三卤甲烷生成势也较大.而过渡亲水性有机酸由于含量和三卤甲烷生成活性较低,三卤甲烷生成势也较低. 相似文献