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91.
The interannual variability of East Asian Monsoon and its relationship with SST in a coupled Atmosphere-Ocean-Land climate model 总被引:4,自引:1,他引:4
Wang Huijun 《大气科学进展》2000,17(1):31-47
1.IntroductionThelargestinterannualvariabilityassociatedwiththeENSOcycleexistsinmonsoonregionsliketheAfricanmonsoon,Australianmonsoon,Pan--AmericanmonsoonandAsianmonsoon(RopelewskiandHalpert,1987;WebsterandYang,1992;JuandSlingo,1995).OnebasicquestionishowtorepresenttheAsianmonsoonanditsvariability.WebsterandYang(1992)foundareasonableindexbyaveragingthezonalwindshearbetween850hpaand200hpaovertheSouthAsianregion(40--110E,0--20N)todescribetheSouthAsianmonsooncirculationanditsvariability.… 相似文献
92.
在研究和建立了多跑道障碍物限制面三维模型的基础上,基于G IS,开发了机场三维净空管理系统。该系统可按照相应标准自动生成单跑道特别是多跑道障碍物限制面、辅助进行净空管理,可极大地减少机场选址与规划中的超障物评定的工作量,显著提高净空管理效率,具有广阔的应用前景。 相似文献
93.
通过大量的现场调查数据与统计工作结果,采用了多种岩体质量分级评价方案,对澜沧江某水电站左岸地下式厂房岩体质量进行了精细的评价,最后将各种结果进行对比分析,得到一个合理、科学的综合岩体质量综合评价分级。并根据评价结果,作出了研究区坝址左岸地下式厂房岩体在不同高程的岩体质量分区图,为下一步的参数选取工作奠定了必要的基础。 相似文献
94.
Combined data of physical property, benthic foraminifera, and stable isotopes from ODP Sites 1148, 1146, and 1143 are used to discuss deep water evolution in the South China Sea (SCS) since the Early Miocene. The results indicate that 3 lithostratigraphic units, respectively corresponding to 21-17 Ma, 15-10 Ma, and 10-5 Ma with positive red parameter (a*) marking the red brown sediment color represent 3 periods of deep water ventilation. The first 2 periods show a closer link to contemporary production of the Antarctic Bottom Water (AABW) and Northern Component Water (NCW), indicating a free connection of deep waters between the SCS and the open ocean before 10 Ma. After 10 Ma, red parameter dropped but stayed higher than the modern value (a*=0), the CaCO3 percentage difference between Site 1148 from a lower deepwater setting and Site 1146 from an upper deepwater setting enlarged significantly, and benthic species which prefer oxygen-rich bottom conditions dramatically decreased. Coupled with a major negative excursion of benthic δ13C at ~10 Ma, these parameters may denote a weakening in the control of the SCS deep water by the open ocean. Probably they mark the birth of a local deep water due to shallow waterways or rise of sill depths during the course of sea basin closing from south to east by the west-moving Philippine Arc after the end of SCS seafloor spreading at 16-15 Ma. However, it took another 5 Ma before the dissolved oxygen approached close to the modern level. Although the oxygen level continued to stabilize, several Pacific Bottom Water (PBW) and Pacific Deep Water (PDW) marker species rapidly increased since ~6 Ma, followed by a dramatic escalation in planktonic fragmentation which indicates high dissolution especially after ~5 Ma. The period of 5-3 Ma saw the strongest stratified deepwater in the then SCS, as indicated by up to 40% CaCO3 difference between Sites 1148 and 1146. Apart from a strengthening PDW as a result of global cooling and ice cap buildup on northern high latitudes, a deepening sea basin due to stronger subduction eastward may also have triggered the influx of more corrosive waters from the deep western Pacific. Since 3 Ma, the evolution of the SCS deep water entered a modern phase, as characterized by relative stable 10% CaCO3 difference between the two sites and increase in infaunal benthic species which prefer a low oxygenated environment. Thesubsequent reduction of PBW and PDW marker species at about 1.2 Ma and 0.9 Ma and another significant negative excursion of benthic δ13C to a Neogene minimum at ~0.9 Ma together convey a clear message that the PBW largely disappeared and the PDW considerably weakened in the Mid-Pleistocene SCS. Therefore, the true modern mode SCS deep water started to form only during the "Mid-Pleistocene climatic transition" probably due to the rise of sill depths under the Bashi Strait. 相似文献
95.
我国省域工业主导产业的遴选与发展 总被引:1,自引:0,他引:1
工业主导产业在国民经济发展中起着决定性和指向性的作用.主导产业的选择是经济发展阶段的重要课题.依据6个量化指标,从4个维度对“十一五”期间主导产业进行遴选,发现以能源及相关产业为代表的重化工业是各省的重点,高新技术产业成为主导产业的省份较少,劳动密集型产业依然是东部发达省市的重点,预期中的产业转移并未实现;以行业为变量对各省份的主导产业进行聚类分析,可将31个省份划分为5类,反映了我国各省份主导产业布局特点;在此基础上,依据产业生命周期理论和各地区“十二五”发展趋势,提出了相应的对策建议. 相似文献
96.
Natural Hazards - In order to examine the height of a fractured water-conducting zone due to the presence of a fault, a typical working face in the Baodian Coal Mine which is located in the Yanzhou... 相似文献
97.
作为社会化媒体的重要类型,微博已经成为继新闻网站、论坛、博客之后,网络舆论生成的主要载体,"微博问政"成为热点和趋势,政务微博也成为政府信息公开、发布权威信息、提供公共服务、加强政民互动、引导网络舆论的重要平台。随着政务微博的快速发展,一系列新问题、新挑战也逐步显现。本文结合国土资源部政务微博的现状,就如何使用政务微博为民服务,提高政务微博应用水平,促进政务微博的健康发展,提升政府公信力,提出了对策建议。 相似文献
98.
99.
从围护结构节能与防火一体化思路出发,提倡钢筋混凝土结构保温一体化建筑体系和砌体结构保温一体化建筑体系;尤其主张在我国建筑工业化全面升级的基础上大力开发与推广保温型混凝土预制装配化技术,统一建筑模数,实现标准化与多样化;针对预制装配化保温型混凝土在梁、构造柱等容易出现的冷、热桥问题的部位,创新式提出以相变储能材料与建筑结构相融合来提高建这些部位的热工性能,减少温度梯度;从系统上做到保温与建筑同寿命、免维护、工序少,工期短、耐火等,从而真正实现低碳,构建建筑围护结构节能防火一体化建筑体系。 相似文献
100.
ChenChen Fang YongQiang Xiong Yun Li QianYong Liang TongShan Wang YongXin Li 《中国科学:地球科学(英文版)》2016,59(2):362-370
On the basis of the results of simulation experiments, now we better understand the contribution of high carbon number hydrocarbons to diamondoid generation during thermal pyrolysis of crude oil and its sub-fractions(saturated, aromatic, resin, and asphalene fractions). However, little is known about the effect of volatile components in oil on diamondoid generation and diamondoid indices due to the lack of attention to these components in experiments. In this study, the effect of volatile components in oil on diamondoid generation and maturity indices was investigated by the pyrolysis simulation experiments on a normal crude oil from the HD23 well of the Tarim Basin and its residual oil after artificial volatilization, combined with quantitative analysis of diamondoids. The results indicate that the volatile components(≤n C12) in oil have an obvious contribution to the generation of adamantanes, which occurs mainly in the early stage of oil cracking(Easy Ro1.0%), and influences the variations in maturity indices of adamantanes; but they have no obvious effect on the generation and maturity indices of diamantanes. Therefore, some secondary alterations e.g., migration, gas washing, and biodegradation, which may result in the loss of light hydrocarbons in oil under actual geological conditions, could affect the identification of adamantanes generated during the late-stage cracking of crude oil, and further influence the practical application of adamantane indices. 相似文献