电厂山区性河流取水工程安全设计分析

通过对代表性山区河流电厂的取水工程安全实例分析 ,根据取水方式不同 ,建议应采取的措施分为 :直接在天然河道上布置取水构筑物时 ,取水头部上下端加设三角形挡沙板 ,取水口上游设导沙丁坝 ,抬高取水头高程和进水底槛高程 ,并且可考虑设置两套取水系统 ,枯水期直接利用河道取水头取水 ,洪水期从移动式泵车取水 ;在河道上设置拦河低坝取水时 ,必须设置配套取水防沙设施 ,如排沙闸或冲沙闸 ,进水闸前设导沙坝 ,冲刷闸前设导沙坎 ,泄洪闸前设冲沙廊道和导流堤 ,还可在河道上设置潜水丁坝等。     

沙丘结皮层形成过程的土壤微生物和土壤酶活性

人工植被的固定沙丘结皮层土壤微生物数量多,土壤酶活性强,结皮层较厚,韧性也强,其次是半固定沙丘结皮层.流动沙丘表层较差.固定沙丘和半固定沙丘相同土层土壤微生物数量、土壤酶活性强度虽然不同,但其消长以及土壤理化性质变化趋势基本相同.流动沙丘各土层则明显不同于前者。     

超稠油废水处理的实验研究

针对超稠油废水污染的问题 ,确定采用混凝沉降、砂滤、活性炭吸附处理超稠油废水 ,处理后的水达到国家排放标准。此方法工艺比较简单 ,处理效果好     

Sand Fences in the Coastal Zone: Intended and Unintended Effects

Sand-trapping fences modify the character of the coastal landscape and change its spatial structure, image, and meaning. This paper examines the relationship between these changes and fence usage at the municipal level, where most decisions about fence deployment are made. Use of fences in 29 municipalities on the developed coast of New Jersey is examined over a 6-year period. Interviews with municipal officers indicate that wooden slat sand-trapping fences are used primarily to build dunes to provide protection against wave uprush and flooding, but they are also used to control pedestrian traffic and demarcate territory. These uses result in changes in landforms and habitats. An aerial video inventory of fences taken in 2002 indicates that 82% of the shoreline had fences and 72% had dunes. Single and double straight fence rows are the most commonly used. Fences are often built to accomplish a specific primary purpose, but they can cause many different and often unanticipated changes to the landscape. The effects of a sand fence change through time as the initial structure traps sand, creates a dune that is colonized by vegetation, and becomes integrated into the environment by increasing topographic variability and aesthetic and habitat value. Sand fences can be made more compatible with natural processes by not placing them in locations where sources of wind blown sand are restricted or in unnatural shore perpendicular orientations. Symbolic fences are less expensive, are easy to replace when damaged, are less visually intrusive, and can be used for controlling pedestrian access.     

外界辐射热对浸油沙层着火特性影响研究

通过实验研究了施加辐射热后浸油沙层的着火特性.实验中使用柴油为燃料,沙层为多孔介质,自制的施加辐射热测量闪点和燃点的设备,研究了施加辐射热后,沙油质量比、沙粒直径以及外界辐射热通量对浸油沙层着火特性的影响.结果表明,沙粒直径及沙油质量比不变,随着辐射热通量的增大,浸油沙层的闪点、燃点降低到某一值后不再变化;施加辐射热通量,浸油沙层的闪点、燃点随沙油质量比的增加而升高,不再出现闪点和燃点的最小值点;沙粒直径对浸油沙层的闪点和燃点有影响.     

北方沙尘暴对杭州大气环境的影响及应对措施

简述了我国沙尘天气的形成与分级情况。分析了我国沙尘天气的发展趋势与原因及其对杭州大气环境的影响情况。指出我国沙尘天气的发展有越演越烈的趋势 ,对杭州大气环境的影响时间延长 ,频次增加 ,危害程度加重 ,范围扩大。对防治沙尘天气污染大气环境提出了应对措施。     

Degradation of anionic surfactants during drying of UASBR sludges on sand drying beds

Anionic surfactant (AS) concentrations in wet up-flow anaerobic sludge blanket reactor (UASBR) sludges from five sewage treatment plants (STPs) were found to range from 4480 to 9233mgkg(-1)drywt. (average 7347mgkg(-1)drywt.) over a period of 18 months. After drying on sand drying beds (SDBs), AS in dried-stabilized sludges averaged 1452mgkg(-1)drywt., a reduction of around 80%. The kinetics of drying followed simple first-order reduction of moisture with value of drying constant (k(d))=0.051d(-1). Reduction of AS also followed first-order kinetics. AS degradation rate constant (k(AS)) was found to be 0.034d(-1) and half-life of AS as 20 days. The order of rates of removal observed was k(d)>k(AS)>k(COD)>k(OM) (drying >AS degradation>COD reduction>organic matter reduction). For the three applications of dried-stabilized sludges (soil, agricultural soil, grassland), values of risk quotient (RQ) were found to be <1, indicating no risk.     

Conservation and management of the mediterranean coastal sand dunes in Israel

The aims of this study are to review the current situation of the Israeli Mediterranean coastal sand dunes, to examine the causes for this situation, and to propose options for future conservation and management of the protected dune areas based on ecological, environmental, landscape and recreational demands and interests. The coastal dunes of Israel are characterized by diverse plant communities, with 173 plant species occurring on sand (8.2% of the total flora of Israel) including many endemic species (26% of all endemic species in Israel). Most of the species are annuals. The importance of the coastal strip as a centre of floral and faunal speciation is also manifested in the existing sand-bound animals. However, many species are rare. This is mainly due to the extensive industrial and urban development along the coastal plain and the direct and indirect destruction of the remaining open dune areas by tourism, recreation and sand mining. Only ca. 17% of the Israeli coastal dunes are still of good or reasonable ecological value, while < 5% of this area has been designated as protected area. Management policies differ from place to place and depend on local objectives. These objectives derive mainly from the knowledge and data that exist for each location, and its statutory status. Since 1995 several projects, which aim to develop integrated management tools for nature conservation and recreation uses for all coastal sand dunes in Israel have been conducted. These projects are summarized in the present paper.     

The development of a digital terrain model for the geomorphological engineering of the ‘rolling’ foredune of Terschelling,the Netherlands

The foredunes form an important element of the line of defence which protects the low-lying parts of the Netherlands from the sea. The foredune of the eastern part of the Wadden island of Terschelling has been managed as a ‘rolling’ foredune to maximize the amount of sand available in times of emergency. Following a decision of the Dutch Government to maintain the coastline of 1990, this foredune will now be stabilized. A plan is made to reshape the morphology of the foredune according to a geomorphological design. A simulation model was developed to produce a Digital Terrain Model with the required geometrical information. The transformation which is on the macro-level scale can be achieved within the envisaged medium-scale planning period of five years only by applying earth-moving machinery, placing fences or planting sand-trapping vegetation.     

不溶性腐殖酸对六价铬离子的吸附研究

研究了不溶性腐殖酸（IHA）对六价铬（Cr（Ⅵ））的吸附作用及反应接触时间、pH、IHA投加量、温度等对吸附作用的影响,确定了最佳反应条件。实验表明,在反应接触时间60min、酸性pH7左右的水溶液条件下,IHA对Cr（Ⅵ）去除率可达98%。绘制了IHA对Cr（Ⅵ）的反应动力学曲线和吸附等温线。