炼化企业罐底油泥处理技术研究进展

炼化企业原油罐、成品油罐及污油罐定期清理过程,会产生大量罐底油泥。罐底油泥含油量大,处理成本高,环境危害严重,是炼化行业关注的重点。有效回收油分和降低处理成本是近几年罐底油泥处理技术研究的主要内容。介绍了以调质-分离、化学法和生物法为主的罐底油泥处理技术及各技术对罐底油泥的处理现状,总结了3种处理方法存在的优缺点及今后的发展方向。     

深水型湖泊底泥NH4+-N释放的环境因子影响实验研究

通过对深水型人工湖泊(以福州市山仔水库为例)底泥NH4 -N释放特性进行实验研究,该实验在厌氧状态下进行,主要是以氨态氮溶出为主,这是一个物理过程,是由于分子的扩散造成的,分析了环境因子对底泥NH4 -N释放特性的影响及其原因.得出了温度、上覆水本身NH4 -N浓度和底泥粒径对底泥NH4 -N释放影响的动力曲线.同时说明了湖泊底泥NH4 -N释放对湖泊水质存在着潜在的危险性.为城市深水湖泊底泥疏浚和富营养化治理提供依据.     

黄河水中脯氨酸对Pb(Ⅱ)与表层沉积物相互作用的影响

研究了黄河干流内蒙古清水河段黄河水中表层沉积物与铅（Ⅱ）相互作用以及脯氨酸对其的影响，得出了离子交换率E％－pH关系曲线，该曲线的突跃范围及最大离子交换率E％。结果表明：在我们研究的范围内，脯氨酸深度增加，离子交换率E％增大，并且在pH为0－10的范围内，随着pH值增大，离子交换率E％增大；交换剂为转化沙时的离子交换率E％比未转化沙大。     

低层大气中固体粒子运动及其物理模拟

对于大气边界层中的固体粒子的风致运动－较大粒子的蠕动跃动和较小粒子悬浮－的主要特征作了介绍，着重介绍了在悬浮粒子运动的物理模拟研究方面的一些成果；复杂地形物低层大气湍流会显地提高起尘速率并改变降尘量的分布；有一定我向厚度的风障除了屏蔽效应－－即背风侧平均风速的减小－－外，还滕了终进入空气的灰尘数量的“宏观吸附效应”；总结了模拟悬浮粒子运动的风洞实验所应遵循的相似性准则，并提出了模拟防尘风障的中的     

填埋场垃圾堆体斜面压实工程试验研究

通过现场工程试验对填埋垃圾堆体斜面压实效果进行了影响因素的研究．试验证明：在垃圾填埋作业过程中，压实机械对填埋垃圾堆体斜面压实的效果受垃圾堆体斜面坡度、垃圾堆体构造层厚度、压实机械行程次数以及压实机械的行驶方向等因素影响显著．实验结果表明：为取得最佳的垃圾堆体斜面压实效果，斜面最佳坡度在1：5～1：4之间，最佳垃圾摊铺厚度在0．6m～0．7m之间，最佳机械行程次数为3次，压实机械的行驶方向为坡下向坡上．     

臭氧层耗损研究的进展评述

８０年代以业南极上空平流层臭氧层不断减少，１９９８年９月臭氧洞的面积和深度达历史最高记录。平流层臭氧耗损会导致到达在面地的有害紫外线增加，损害人类的健康和破坏地球生态。介绍了了臭氧层损耗的机理、现状、该领域的研究进展和复旦大学的研究结果。     

岷山北坡高海拔区草本植物群落特征及主要植物功能群C、N、P含量分析

海拔是影响物种多样性格局的决定性因素之一,对生态系统格局与过程起着重要作用。运用回归分析、相关分析、Duncan多重比较和Pearson相关系数检验对岷山北坡高海拔2300—2900 m草本群落特征、群落初级生产力及不同植物功能群进行分析。结果表明:样地共调查出草本植物20科35属44种,菊科、百合科和蔷薇科的物种数分别占总物种数的比例为25%,14%和11%,表现出明显的优势性。草本群落的生物量均与海拔梯度的相关性不显著(P>0.05),且随海拔升高均表现出先增后减的总体趋势;植物盖度、物种丰富度、密度均与海拔表现出极显著负相关关系(P<0.001),而植物高度与海拔表现出极显著正相关关系(P<0.01)。从功能群的角度分析,随着海拔梯度的不断升高,禾本科、菊科以及杂类草3个植物功能群的叶碳含量(LCC)和根碳含量(RCC)整体呈上升趋势;叶磷含量(LPC)整体都呈下降趋势,而禾本科的根磷含量(RPC)呈上升趋势,菊科和杂类草表现出先升后降的趋势;叶氮含量(LNC)禾本科呈下降趋势,菊科呈上升趋势,杂类草呈先上升后下降的变化趋势,根氮含量(RNC)禾本科和杂类草的呈上升趋势,而菊科表现出先上升后下降的趋势。研究结果初步揭示了岷山北坡不同海拔梯度草本植物群落特征及其生物量的变化特征,以及物种多样性和主要植物功能群碳、氮、磷元素在海拔梯度上的分布差异,为今后岷山北坡草本群落分布格局和生物地球化学循环的研究提供科学依据。     

Dynamics of Turbulence in Low-Speed Oscillating Bottom-Boundary Layers of Stratified Basins

This paper focuses on the impact of an oscillating low-speed current on the structure and dynamics of the bottom-boundary layer (BBL) in a small stratified basin. A set of high-resolution current profile measurements in combination with temperature-microstructure measurements were collected during a complete cycle of the internal oscillation (`seiching') in the BBL of Lake Alpnach, Switzerland. It was found that even a relatively long seiching period of 24 hours significantly changed the form of the near-bottom current profiles as well as the dynamics of the turbulent dissipation rate compared to the steady-state law-of-the-wall. A logarithmic fit to the measured current profiles starting at a distance of 0.5 m above the sediment led to inconsistent estimates of both friction velocity and roughness length. Moreover, a phase lag between the current and the turbulent dissipation of 1.5 hours and a persistent maximum in the current profile at a height of 2.5 to 3 m above the sediment were observed. The experimental findings were compared to the results of a k- turbulence model and showed good agreement in general. Specifically, the inconsistent logarithmic fitting results and the observed phase lag were reproduced well by the model.     

Weak-wind mesoscale meandering in the nocturnal boundary layer

This study examines the strength and statistical behavior of mesoscale motions on time scales up to 1 h using eight data sets over different surface types. The mesoscale motions include internal gravity waves, microfront-like structures, horizontal modes, and a complex variety of other signatures, perhaps resulting from superposition of different modes. With weak large-scale flow, the mesoscale motions lead to meandering of the wind direction, as found in previous studies. However, the meandering often takes the form of sudden wind shifts rather than oscillation of wind direction. The relative strength and impact of such mesoscale motions are examined in terms of the constancy of the wind vector, the within-record standard deviation of the wind direction and the ratio of a meso-velocity scale to the speed of the large-scale flow. The strength of the mesoscale flow varies by an order of magnitude between nights at a given site and varies systematically between sites. The statistics of the vertical structure of such motions are examined for two of the data sets, both with sonic anemometers at seven levels.     

Effects of Earthworm Invasion on Plant Species Richness in Northern Hardwood Forests

Abstract:  The invasion of non-native earthworms ( Lumbricus spp.) into a small number of intensively studied stands of northern hardwood forest has been linked to declines in plant diversity and the local extirpation of one threatened species. It is unknown, however, whether these changes have occurred across larger regions of hardwood forests, which plant species are most vulnerable, or with which earthworm species such changes are associated most closely. To address these issues we conducted a regional survey in the Chippewa and Chequamegon national forests in Minnesota and Wisconsin (U.S.A.), respectively. We sampled earthworms, soils, and vegetation, examined deer browse in 20 mature, sugar-maple-dominated forest stands in each national forest, and analyzed the relationship between invasive earthworms and vascular plant species richness and composition. Invasion by Lumbricus was a strong indicator of reduced plant richness in both national forests. The mass of Lumbricus juveniles was significantly and negatively related to plant-species richness in both forests. In addition, Lumbricus was a significant factor affecting plant richness in a full model that included multiple variables. In the Chequamegon National Forest earthworm mass was associated with higher sedge cover and lower cover of sugar maple seedlings and several forb species. The trends were similar but not as pronounced in Chippewa, perhaps due to lower deer densities and different earthworm species composition. Our results provide regional evidence that invasion by Lumbricus species may be an important mechanism in reduced plant-species richness and changes in plant communities in mature forests dominated by sugar maples.