黄河三角洲河道沉积规律研究Ⅱ. 建林边滩沉积作用机理     

范德江  陈彰榕  栾光忠 《中国海洋大学学报(自然科学版)》2001,31(2):237-242

通过对建林边滩沉积物粒度分布、粒度参数及水体流变性质的分析，阐述了黄河三角洲上河道水流属于牵引流范畴，与低含沙水流无本质上的差别，并探讨沉积物搬运和沉积的基本特征。  相似文献   

离子色谱分析在黄土和粉尘研究中的应用   总被引：1，自引：0，他引：1  

王丹  屈文军  张小曳  严立文  曹国良 《海洋地质与第四纪地质》2005,25(1):113-118

黄土中存在着大量的碱金属及碱土金属，以往的测试方法多为原子吸收和ICP—MS，离子色谱法在测试黄土样品的碱金属和碱土金属元素含量中应用不多。将黄土地质标准样品进行消解后用离子色谱进行测试，测试效果良好，重复测试的相对标准偏差小于5％，与推荐值的相对误差小于5％，准确度和精密度符舍相关的质量控制要求。本实验方法测试的离子含量都在仪器响应呈线性的最佳测试范围之内，标准曲线经回归后相关系数均达到0．9999。黄土样品的分析结果与粉尘气溶胶样品的离子分析结果对比表明，此方法对于探讨粉尘起源以及沙尘暴天气的研究具有重要意义。  相似文献   

砷酸根的液—固界面交换吸附研究——pH和Ca(Ⅱ)的影响     

赵卫红  张正斌 《中国海洋大学学报(自然科学版)》1997,(2)

研究ｐＨ和Ｃａ（Ⅱ）对砷酸根在海水与ＮａＣｌ介质中对水合氧化物和粘土矿物上交换吸附的影响：（１）在酸性条件下和海水及ＮａＣｌ介质中，砷酸根在针铁矿上的交换率Ｅ（％）—ｐＨ曲线呈平顶峰型、在δ－ＭｎＯ呈峰型、在粘土上分别呈双峰型和肩峰型。这是砷酸根存在多种形式与固体表面发生离子／配位子交换以及介质中阴离子竞争交换吸附共同作用的结果。（２）在碱性条件下的海水介质中，砷酸根与水合氧化物和粘土矿物的Ｅ（％）—ｐＨ曲线都呈Ｖ型，这是因为生成了具有一定结构的液—固界面三元络合物之故。（３）在ＮａＣｌ介质中，Ｃａ加入起促进作用，再次证明液—固界面三元络合物生成机理与Ｖ型曲线的内在关系  相似文献   

Dynamics and Variability of Terra Nova Bay Polynya   总被引：1，自引：0，他引：1  

Giannetta Fusco  Daniela Flocco  Giorgio Budillon  Giancarlo Spezie  Enrico Zambianchi 《Marine Ecology》2002,23(S1):201-209

Abstract. We present a process study on the dynamics and variability of the Terra Nova Bay polynya in the western sector of the Ross Sea. The air-sea heat exchange is known to be particularly large in polynya during the winter, when differences between air and sea temperatures are large. We apply a 1-D model (Pease, 1987; Van Woert, 1999a, 1999b), which is modified in the latent heat parameterisation in order to account for time-dependent relative humidity and cloud coverage. Furthermore, the Ice Collection Depth is correlated linearly with a variable wind speed. The model is forced with two different meteorological data sets: the operational analysis of the European Center for Medium Range Weather Forecasts atmospheric data set and the meteorological parameters measured by an Automatic Weather Station located on the coast of Terra Nova Bay. The results are compared in terms of polynya extension, ice, and High Salinity Shelf Water production. According to the two different wind velocities, the results obtained from the different data sets clearly differ. Qualitatively, however, the results are in good agreement.  相似文献   

Exchange flow of oil and sea-water in a ruptured submarine pipeline     

C. Kranenburg 《Applied Ocean Research》1984,6(1):23-30

The rupture of a submarine oil pipeline starts various mechanisms leading to an oil spill. Among these mechanisms the leakage of oil driven by the difference in specific gravities of oil and sea-water is difficult to estimate. A simple mathematical model has been developed and laboratory experiments have been carried out to obtain an insight into the density-driven exchange flow and to determine the leak rate. The mathematical model is predictive and takes account of the effects of friction, inclination of the pipeline, and inertia of the fluid. The experiments were done in a horizontal model pipeline. Theoretical and experimental results are in satisfactory agreement.  相似文献   

Consequences of winter upwelling events on biogeochemical and phytoplankton patterns in a western Galician ria (NW Iberian peninsula)   总被引：3，自引：0，他引：3  

Ricardo Prego  Dafne Guzmn-Zuiga  Manuel Varela  Maite deCastro  Moncho Gmez-Gesteira 《Estuarine, Coastal and Shelf Science》2007,73(3-4):409-422

The consequences of two upwelling events in mid- (MW) and late (LW) winter on biogeochemical and phytoplankton patterns were studied in the Pontevedra Ria and compared with the patterns measured under typical winter conditions and under a summer upwelling event. Thermohaline patterns measured during the mid-winter upwelling event (MW-up) revealed the intrusion of saltier seawater (35.9) into the ria associated with the Iberian Poleward Current (IPC). During the late-winter upwelling event (LW-up), the seawater which had welled up into the ria showed characteristics of the Eastern North Atlantic Central Water mass (ENACW). In both cases the measured water residence time (4 days during MW-up and 10 days during LW-up) was related to both meteorological and fluvial forcing. This residence time contrasts with that of summer upwelling (7 days) and with that estimated under unfavorable upwelling atmospheric conditions (2–4 weeks). During MW-up, the ria became poor in nutrients due to continental freshwater dilution, associated with the shorter residence time of the water, and the intrusion of IPC, which is a water body poor in nutrient salts: 2.9 μM of nitrate, 0.1 μM of phosphate and 1.5 μM of silicate. During this event, the ria exported 3.4 mol_DIN s⁻¹, compared with 6.9 mol_DIN s⁻¹ in non-upwelling conditions. Phytoplankton showed a uniform distribution throughout the ria, as during unfavorable upwelling conditions, and was characterized by the dominance of diatoms, mainly Nitzschia longissima and Skeletonema costatum. During LW-up, a nutrient depletion in the photic layer also occurred, but as a result of a phytoplankton spring bloom developing at this time. The ria was a nutrient trap where 4.1 mol_DIN s⁻¹ were processed by photosynthesis. This budget is three times higher than the one under non-upwelling conditions. In contrast with the MW-up, which had no effect on primary production, during LW-up the ria became more productive, although not as productive as during a summer upwelling event (9.9 mol_DIN s⁻¹). The taxonomic composition of the phytoplankton community did not change noticeably during LW-up and the summer upwelling, with the same species present and changing only in relative proportions. Diatoms were always the dominant microphytoplankton community, with Pseudonitzschia pungens, Thalassionema nitzschioides and several species of Chaetoceros as characteristic taxons.  相似文献   

氨基酸在粘土高岭石上吸附等温线的研究   总被引：2，自引：0，他引：2  

刘效兰  张正斌 《海洋科学》2002,26(9):1-4

研究了4种氨基酸（甘氨酸，赖氨酸，天冬氨酸，谷氨酸）在粘土高岭石上的吸附等温线以及金属铜离子对其等温线的影响。研究表明，氨基酸在高岭石上的吸附等温线以及金属铜离子存在时的吸附等温线均属Langmuir型等温线；铜离子浓度增加时，其等温线斜率也增加，并认为体系可形成Ⅰ型三元表面络合物，铜离子对氨基酸在高岭石上等温线影响的规律和在相同体系中它对氨基酸在高岭石上交换吸附百分率E（%）-pH曲线的影响规律相一致。  相似文献   

礁膜配子放散条件的研究   总被引：2，自引：0，他引：2  

陈昌生 《台湾海峡》1996,15(2):154-158

本文报道了礁膜配子的放散与温度、光照、比重的关系。结果表明，自然海区的礁膜在白天大量放散配子。配子放散的适宜温度为１９－２１℃；光照为２０００－５０００ｌｘ时能促进配子大量放散出来；配子放散的适宜比重为１．０５－１．０２５；这些研究结果将为礁膜人工育苗提供一些科学依据。  相似文献   

用新显色剂3-甲氧基-甲亚胺H光度测定海水中的硼     

潘教麦  王芳  徐钟隽 《海洋科学》1994,18(1):64-66

采用新试剂３－甲氧基－甲亚胺Ｈ测定海水中的硼，加入ＥＤＴＡ和酒石酸掩蔽各种干扰离子，不须分离可直接测定，方法简便、快速、准确。  相似文献   

红树植物白骨壤叶片衰老过程中叶肉细胞Ca2+水平的变化     

杨盛昌  谢潮添  陈文列 《台湾海峡》2003,22(2):145-149,T001

用焦锑酸钙沉淀的电镜细胞化学方法，研究了白骨壤叶片衰老过程中叶肉细胞Ca^2 水平的变化．结果表明，在白骨壤幼叶和成熟叶叶肉细胞中，焦锑酸钙沉淀颗粒大量出现在液池和细胞间隙中，细胞壁中也可见少量沉淀，而细胞基质中则看不到焦锑酸钙沉淀．在衰老叶中，细胞基质和细胞膜上焦锑酸钙沉淀增加，而液泡和细胞间隙中的锑酸钙沉淀则显著减少，并且叶绿体外膜部分破损，结构破坏，核膜与液泡膜内部结构模糊，叶绿素含量、净光合速率、气扎手率和蒸腾速率显著下降．Ca^2 的区域性分布的变化与植物叶片衰老密切相关。  相似文献