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排序方式: 共有752条查询结果,搜索用时 15 毫秒
71.
山东乳山海滩岩及其重要科学意义 总被引:2,自引:0,他引:2
乳山海滩岩,经过室内对微体化石、大化石和沉积岩石学研究,查明该岩体具有典型的海滩岩特征:含有两种文石胶结物、滨海相微体古生物和热带大化石。该岩体形成在全新世最佳气侯期,至少有3次成岩期,对研究古环境变化规律具有重要的科学意义。 相似文献
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CIMS工程的重要思想是将企业全部生产经营活动视为有机整体,可以集成与优化。但是,目前我国CIMS工程中PDM与MRPⅡ分系统并未真正实现紧密结合与集成,甚至是彼此分离,无直接衔接。在实践经验的基础上,作者探讨了基于二维模式的PDM与MRPⅡ紧密衔接可行性,提出了实现这一衔接的初步设想 相似文献
74.
介绍了一种涵盖地籍管理过程且在实施过程中简单易行而有效的信息系统,为土地资源的合理开发利用和地籍信息的动态管理了新的途径。 相似文献
75.
Escobar Sebastian Bi Qilong Fettweis Michael Wongsoredjo Samor Monbaliu Jaak Toorman Erik 《Ocean Dynamics》2023,73(6):333-358
Ocean Dynamics - A dynamic two-dimensional depth-averaged (2DH) parameterization for flocculation of cohesive sediments is proposed based on the kinetic model by Winterwerp (J Hydraul Res... 相似文献
76.
In the Rhode River estuarine/watershed area, increased acidity of precipitation from atmospheric acidic deposition has deleterious effects on the freshwater ecosystems. One of the characteristics of an acidic watershed is the mobilization of aluminum from soils to aquatic environment. Increased concentrations of aluminum in surface waters are toxic to living organisms. Detection of long-term changes of acidity and elevated Al concentrations in surface and soil waters is a central issue. In this present paper, the dynamics ofAl speciation in the shallow ground waters from Rhode River watershed 110 (la) were investigated. This research provides a unique, regional analysis of important controls on the transport of Al speciation through the rural watershed of the Chesapeake Bay. 相似文献
77.
Numerical modeling of storm surges in the coast of Mozambique: the cases of tropical cyclones Bonita (1996) and Lisette (1997) 总被引:1,自引:1,他引:0
Alberto José Bié Ricardo de Camargo Alberto Francisco Mavume Joseph Harari 《Ocean Dynamics》2017,67(11):1443-1459
The coast of Mozambique is often affected by storms, particularly tropical cyclones during summer or sometimes midlatitude systems in the southern part. Storm surges combined with high freshwater discharge can drive huge coastal floods, affecting both urban and rural areas. To improve the knowledge about the impact of storm surges in the coast of Mozambique, this study presents the first attempt to model this phenomenon through the implementation of the Princeton Ocean Model (POM) in the Southwestern Indian Ocean domain (SWIO; 2–32°S, 28–85°E) using a regular grid with 1/6° of spatial resolution and 36 sigma levels. The simulation was performed for the period 1979–2010, and the most interesting events of surges were related to tropical cyclones Bonita (1996) and Lisette (1997) that occurred in the Mozambique Channel. The results showed that the model represented well the amplitude and phase of principal lunar and solar tidal constituents, as well as it captured the spatial pattern and magnitudes of SST with slight positive bias in summer and negative bias in winter months. In terms of SSH, the model underestimated the presence of mesoscale eddies, mainly in the Mozambique Channel. Our results also showed that the atmospheric sea level pressure had a significant contribution to storm heights during the landfall of the tropical cyclones Bonita (1996) and Lisette (1997) in the coast of Mozambique contributing with about 20 and 16% of the total surge height for each case, respectively, surpassing the contribution of the tide-surge nonlinear interactions by a factor of 2. 相似文献
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Natural Hazards - This study involved the systematic collation of historical data from local records, government records, etc., as well as disaster data compiled by contemporary researchers.... 相似文献
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