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21.
An optimal interpolation assimilation model for satellite altimetry data is developed based on Princeton Ocean Model (POM), which is applied in a quasi-global domain, by the method of isotropic correlation between sea level anomaly (SLA) and sea temperature anomaly. The perfor- mance of this assimilation model is validated by the modeled results of SLA and the current patterns. Comparisons between modeling and satellite data show that both the magnitudes and distribution patterns of the simulated SLA are improved by assimilation. The most signiˉcant improvement is that meso-scale systems, e.g., eddies, are well reconstructed. The evolution of an eddy located in the northwest Paciˉc Ocean is traced by using the assimilation model. Model results show that during three months the eddy migrated southwestward for about 6 degrees before merging into the Kuroshio. The three dimensional structure of this eddy on 12 August 2001 is further analyzed. The strength of this warm, cyclonic eddy decreases with the increase of depth. The eddy shows di?erent horizontal patterns at di?erent layers, and the SLA and temperature ˉelds agree with each other well. This study suggests that this kind of data assimilation is economic and reliable for eddy reconstruction, and can be used as a promising technique in further studies of ocean eddies as well as other ˉne circulation structures.  相似文献   
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毕源清  李永杰 《江苏地质》2019,43(2):247-252
安徽巢湖苏湾地区构造格架位于郯庐断裂带东侧滁州—苏湾金多金属矿成矿带。对近年来取得的地质成果,包括成矿地质特征、物化探特征、地球化学特征、矿化蚀变特征等进行系统分析研究,认为灯影组中段为研究区主要赋矿层位,是研究区重要找矿远景区,F1断层为主要控岩控矿构造,地磁异常为寻找类似山里许铁铜金矿的远景部位。  相似文献   
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Subsurface flow processes in sloping cropland of purple soil   总被引:3,自引:1,他引:2  
Subsurface flow is a prominent runoff process in sloping lands of purple soil in the upper Yangtze River basin.However,it remains difficult to identify and quantify.In this study,in situ runoff experimental plots were used to measure soil moisture dynamics using an array of time domain reflectometry(TDR) together with overland flow and subsurface flow using isolated collecting troughs.Frequency of preferential flow during rainfall events and the controls of subsurface flow processes were investigated through combined analysis of soil properties,topography,rainfall intensity,initial wetness,and tillage.Results showed that subsurface flow was ubiquitous in purple soil profiles due to welldeveloped macropores,especially in surface soils while frequency of preferential flow occurrence was very low(only 2 cases in plot C) during all 22 rainfall events.Dry antecedent moisture conditions promoted the occurrence of preferential flow.However,consecutive real-time monitoring of soil moisture at different depths and various slope positions implied the possible occurrence of multiple subsurface lateral flows during intensive storms.Rainfall intensity,tillage operation,and soil properties were recognized as main controls of subsurface flow in the study area,which allows the optimization of management practices for alleviating adverse environmental effects of subsurface flow in the region.  相似文献   
24.
A substantial cost of granular iron permeable reactive barriers is that of the granular iron itself. Cutting the iron with sand can reduce costs, but several performance issues arise. In particular, reaction rates are expected to decline as the percentage of iron in the blend is diminished. This might occur simply as a function of iron content, or mass transfer effects may play a role in a much less predictable fashion. Column experiments were conducted to investigate the performance consequences of mixing Connelly granular iron with sand using the reduction kinetics of trichloroethylene (TCE) to quantify the changes. Five mixing ratios (i.e., 100%, 85%, 75%, 50%, and 25% of iron by weight) were studied. The experimental data showed that there is a noticeable decrease in the reaction rate when the content of sand is 25% by weight (iron mass to pore volume ratio, Fe/Vp = 3548 g/L) or greater. An analysis of the reaction kinetics, using the Langmuir-Hinshelwood rate equation, indicated that mass transfer became an apparent cause of rate loss when the iron content fell below 50% by weight (Fe/Vp = 2223 g/L). Paradoxically, there were tentative indications that TCE removal rates were higher in a 15% sand + 85% iron mixture (Fe/Vp = 4416 g/L) than they were in 100% iron (Fe/Vp = 4577 g/L). This subtle improvement in performance might be due to an increase of iron surface available for contact with TCE, due to grain packing in the sand-iron mixture.  相似文献   
25.
为了便于开展冬季水泥混凝土施工气象服务,选用临河和海流图(乌拉特中旗)测站近10a的气象资料分别作为河套和后山地区的气象数据.选取逐日最高气温、最低气温、定时相对湿度、最小相对湿度、降水量、定时风速,经过筛选、统计、计算,得出河套地区水泥施工适宜时段为4月上旬末至10月中旬,后n1地区水泥施工适宜时段为4月中旬末至10月上旬.这一研究结果町以提升冬季建筑施工气象服务的针对性和实用性。  相似文献   
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岩溶地貌是整个鄂西南地区综合价值最高、数量最丰富、可代表全区地质遗迹典型特色的地质遗迹类型,具有重要保护与开发利用价值。基于全省重要地质遗迹调查项目,按照地质遗迹调查标准有关要求,通过对前人成果系统收集整理并开展补充调查,筛选汇总鄂西南全区重要岩溶地貌地质遗迹25处。本文将岩溶地质遗迹分为地表类型、过渡类型、地下类型三种类型,结合典型地质遗迹点对岩溶地貌的形态特征和成因进行分析,为鄂西南地区地质旅游产业高质量发展提供依据。  相似文献   
30.
为探明三角褐指藻(Phaeodactylum tricornutum)对抑食金球藻(Aureococcus anophagefferens)是否具有化感作用,本研究以三角褐指藻和抑食金球藻为实验材料,研究了抑食金球藻在单培养和共培养条件下的生长情况及三角褐指藻培养滤液对其生长和叶绿素荧光参数的影响。结果表明:三角褐指藻对抑食金球藻有明显的化感抑制作用。在单培养体系中,抑食金球藻的生长曲线可用逻辑斯谛增长模型拟合,随着起始密度的增加,环境容量(K)逐渐减小,而抑食金球藻的种群瞬间增长率(r)、进入拐点时间及稳定期细胞密度均较为接近;当三角褐指藻与抑食金球藻以不同起始密度比共同培养时,抑食金球藻的生长均受到了显著地抑制(P<0.05),但其抑制作用并未与三角褐指藻的密度呈明显的线性关系;滤液培养实验发现,10 mL和15 mL三角褐指藻培养滤液的加入可对抑食金球藻的生长产生显著影响(P<0.05),对其叶绿素荧光参数没有影响(P>0.05),25 mL和35 mL三角褐指藻培养滤液的加入可对抑食金球藻的生长和叶绿素荧光参数均产生显著的抑制作用(P<0.05),叶绿素荧光参数Fv/Fm、ΦPSⅡ、alpha的值降低,Ik的值增加,PSⅡ受到损害。  相似文献   
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