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71.
扼要论述了青岛市水资源面临短缺的严重形势,认为解决青岛地区水危机仅靠传统开发水资源方式已很困难,必需积极利用青岛的科技、资源优势,开发新水源。 相似文献
72.
73.
The resonance period of the L-shaped channel in the caisson is predicted analytically for the seawater exchange breakwater of “Applicability Study of the Seawater Exchange Breakwater (1). Korea Ministry of Maritime Affairs and Fisheries (in Korean) (1999a)”. Hydraulic experiments are conducted for a composite breakwater with a rear reservoir that is one of the seawater exchange breakwaters developed by them. For regular waves, the water surface elevation in the channel and the flow rate through the breakwater are measured. For irregular waves, the flow rate through the breakwater and the reflection coefficient on the breakwater are measured. The resonant maximum values in both the surface elevation and the flow rate, and the resonant minimum values in the reflection coefficient are all at wave periods slightly longer than analytically predicted ones. The measured resonance period for irregular waves is closer to the predicted one than for regular waves. If the resonance period of the L-shaped channel is fitted to the dominant period of incident waves, there would be high efficiency of seawater exchange between inside and outside the harbor. 相似文献
74.
The wave force on a seawater intake structure consisting of a perforated square caisson of 400 mm×400 mm size encircling a vertical suction pipe of 160-mm diameter is investigated using physical model studies. The porosity of caisson was varied from 1.6 to 16.9%. Regular and random waves of wide range of heights and periods were used. It is found that the force ratio (ratio of the force on perforated caisson to the force on caisson with zero percent porosity) reduces to an extent of up to 60% with increase in porosity of the caisson from 1.6 to 16.9%. The force ratio was found to increase with increase in relative wave height and reduces with increase in relative width. Multiple regression analysis of the measured data points was carried out and predictive equations for wave force ratios are obtained both for regular and random waves. The results of this investigation can be used in the hydrodynamic design of perforated caissons, which are widely used as seawater intake structures. 相似文献
75.
A high sensitivity, low volume HPLC method to determine soluble reactive phosphate in freshwater and saltwater 总被引:1,自引:0,他引:1
A reverse phase High Performance Liquid Chromatography (HPLC) method was developed to detect soluble reactive phosphate (SRP) in marine and freshwater samples. This technique is scalable over a range of sample volumes from 10 μl to 10 ml, requires minimal sample preparation, and responds linearly from 1 nM to 100 μM (R2>0.964). Standard Murphy–Riley molybdenum blue reagents were used to react with phosphate in samples for analysis. Solid phase extraction tubes were used to clean the mixed complexing reagent prior to combining the reagent with samples. The method was applied to freshwater samples collected in July 2001 along an Andean mountain stream located in the Eastern Cordillera (2400 m) of Peru and marine samples collected in January 2002 within the low marsh of the estuarine Nueces Delta System, Texas Coastal Bend. For method comparison, field samples were analyzed using a standard manual spectrophotometric method. Field sample phosphate concentrations produced from each method were nearly identical. This method offers the advantages of low sample volume (1 ml or less) with high sensitivity, precision, and potential automation. 相似文献
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77.
Innovative applications of capillary zone electrophoresis (CZE) to the determination of inorganic ions in environmental aquatic samples of high salinity and, particularly, in seawater are reviewed. Emphasis is placed on advanced approaches utilized for securing separation performance from being degraded by the presence of matrix salts and for simultaneous separation of ions different in natural abundance. Also covered are methodologies of present or possible use to evolve the method's practical utility to trace-level ions. Surveyed procedures are tabulated for the purpose of facilitating the method selection or further development. In addition, brief background information on basic methodological principles of CZE in inorganic ion analysis is given for a better orientation of those intending or just beginning to put CZE to work. Finally, possible future research trends and developments of CZE in the area are briefly discussed. 相似文献
78.
本文根据现场浮游植物光合作用速率和叶缘素a 的测定值,以及海水光强度的衰减变化,计算了海水消光系数,推导了福建东山湾、罗源湾、厦门西港和闽南-台湾浅滩海域海水消光系数与透明度的经验关系式;讨论了悬浮颗粒对不同深度下浮游植物生长速率的影响。结果表明,福建近岸海域光学参数的差异主要在于悬浮物质的贡献;不同季节,生物活动对光学参数也有所影响。最大光合作用速率一般出现在光衰减为10%~30%,频率分布因子为70%~80%。 相似文献
79.
本文讨论了介绍了用气相色谱法测定海水中无机离子Se(-Ⅱ,O,Ⅳ,Ⅵ);Be(Ⅱ);Cr(Ⅲ,Ⅳ);CH3Hg^+,NO3,NO2,Br,I,CN的测定方法和色谱条件。 相似文献
80.
Xiang Yu Chao Zhan Mengquan Wu Xueli Niu Xueyu Zhang 《Marine Georesources & Geotechnology》2020,38(8):887-895
AbstractTidal waterways perform as the paths through which seawater invades. Their spatial-temporal variation with the shift in Yellow River’s route requires the accurate measurement of their status. Visual interpretation for delineating tidal waterways is inefficient due to a substantial amount of work. Buffer analysis provides an alternative to visual interpretation. However, it is difficult to use the buffer distance threshold to identify tidal waterways from other freshwater bodies. In this study, we present a straightforward method for mapping tidal waterways. First, we adopted the normalized difference water body index (NDWI) to extract water bodies. Waterlines were subsequently delineated based on a morphological opening filter with a kernel of 9?×?9. Finally, tidal waterways were mapped based on the proposed topological relation in ArcGIS. We showed the utility of this approach by mapping tidal waterways in the Yellow River Delta, China. The proposed method enables tidal waterways be mapped precisely and was replicable and universal in other similar studies. 相似文献