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241.
In this paper,the sea surface height and the heat content of the upper ocean are analyzed to retrieve the relationship of interannual variabilities between the tropical western Pacific and eastern Indian Oceans during the 1997~1998 El Ni(n)o event.In the prophase of this El Ni(n)o,the negative sea level anomalies (SLA) occurred in the tropical western Pacific (TWP) firstly,and then appeared in the tropical eastern Indian Ocean (TEI).The negative heat content anomalies (HCA) emerged in the TWP before this El Ni?o burst while the SLA signals developed over there.During the mature stage of this El Ni(n)o,two kinds of signals in the TWP and TEI turned to be the maximum negative sequently.Due to the connected interannual adjustment between the TEI and TWP,we adopted a method to estimate the Indonesian Throughflow (ITF) transport by calculating the HCA budget in the TEI.The indirect estimation of the ITF was comparable to the observation values.Therefore,the anomalies in the TEI had been proved as advecting from the TWP through the ITF during the 1997~1998 El Ni(n)o. 相似文献
242.
曹催晨 《科技情报开发与经济》2003,13(12):297-298
万孪寨引黄工程北干线l号隧洞,长43.9km,已完成5.47km,其余洞段即将施工。该隧洞埋深较大,且大部洞身位于区域地下水位以下,工程地质条件极为复杂,通过充分分析其工程地质问题,提出隧洞掘进施工对策。 相似文献
243.
南水北调西线工程的自然环境、区域地质环境和经济技术环境都具有特殊性 ,区内工程地质勘察特别是隧洞工程的勘察具有较大的难度。针对南水北调西线工程特点应进行工程地质勘察方法和相关工程地质问题的研究。首先前期工程地质勘察应建立概率统计的思想 ,侧重于基本规律的把握。第二应充分利用计算机技术 ,开发出适合隧洞快速施工的工程地质分析评价和决策软件 ,使基本地质资料的采集、分析、评价、决策做到快速、准确。第三应研究适合隧洞施工的勘察技术 ,包括高精度解析遥感技术、深埋隧洞物探方法、超前钻探设备和探测装置 ,也包括数据采集方法、快速编录系统以及施工地质资料处理系统等。 相似文献
244.
华北燕山地区和新疆乌伦古河地区发育有过碱性A型花岗岩类。前者出现于板内,富Nb、低εNb而高εSr;后者形成于造山晚期,贫Nb、高εNd而低εSr。总结了它们的地质学、岩石学、主要和痕量元素地球化学资料,报道了Rb-Sr和 Sm-Nd同位素分析结果;以此为基础探讨了这类岩石的物质来源及其亚类划分问题;提出两类岩石分别来源于富集性储库与亏损性储库的看法。 相似文献
245.
246.
247.
《Journal of Natural History》2012,46(37-38):2437-2456
In this paper current knowledge on the diversity of the gastropod cephalaspidean genus Haminoea from India is revised. A comprehensive literature review was undertaken and novel specimens were collected. Specimens from India were DNA barcoded using the gene cytochrome c oxidase sub-unit I and a Bayesian gene tree together with an Automatic Barcode Gap Discovery (ABGD) species delimitation analysis were inferred to compare Indian samples with species from the Indo-West Pacific. The most comprehensive DNA data set to date of the genus Haminoea is included and new morpho-anatomical features of Indo-West Pacific species were generated through fine anatomical work and scanning electron microscopy. A critical appraisal of previous records of the country is included and a new species, Haminoea aptei sp. nov., is described from the Andaman Islands and Lakshadweep Islands, India.www.zoobank.org/urn:lsid:zoobank.org:pub:90C191A9-5CA6-4BC6-84E3-B1A26674FA1B 相似文献
248.
《Journal of Natural History》2012,46(2):475-485
The pelagic penaeid shrimp Funchalia taaningi Burkenroad, 1940 is redescribed based on specimens collected mainly in the central Pacific Ocean. The petasma of the male is illustrated for the first time. The distribution of the species is extended into the eastern Indian Ocean based on a female collected in 1964 during the International Indian Ocean Expedition. Two males of Funchalia villosa (Bouvier, 1905), also collected during the International Indian Ocean Expedition, are recorded from the eastern Indian Ocean, extending the known distribution of this species. 相似文献
249.
《Journal of Natural History》2012,46(6):1387-1395
Hargicotyle magna sp. nov., Hargicotyle paralonchuri sp. nov., Hargicotyle sciaenae sp. nov., from the gills of the Sciaenids Sciaena fasciata, Paralonchurus peruanus and Sciaena deliciosa, respectively, and Hargicotyle menticirrhi sp. nov. from the gill and mouth of Menticirrhus ophicephalus are described from the northern Chilean and central Peruvian coast. Distinct characteristics of the new species are the distribution of the vitelline follicles; the number and distribution of the testes, the size, shape and number of larval hooks; and the presence of one or two suckers in each clamp. 相似文献
250.