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941.
This paper reports high-resolution biomarker records of the last 260 ka for core MD05-2904 from the northern South China Sea (SCS). The sea surface temperature (SST) record using the U37^k', index reveals a minimum of 21.5℃(MIS 2) and a maximum of 28.3℃(MIS 5.5), for a temperature difference of almost 7℃, and provides the longest high-resolution U37^k' SST record in northern SCS. The content of odd-number long chain n-alkanes and several n-alkanes indexes such as the CPI, ACL and the C31/C27 ratio, all reveal generally higher values during the glacials and lower values during the interglaclals. Terrestrial input as Indicated by n-alkane content was mostly controlled by sea-level changes: During the glacials, lower sea-level exposed the continental shelf to enable rivers to transport more terrestrial materials to the slope; and the situation reverses during the interglacials. The n-alkane indexes changes reveal more n-alkanes from contemporary vegetation during glacials as a result of the proximity of the core site to the source region, while the increases in ACL and C81/C27 ratio during glaclals indicate a change to more grassy vegetation. However, the highest values for CPI, ACL and the C81/C27 ratio all occurred during late MIS 3, and it was suggested that this period was characterized by a strong summer monsoon-dominated humid climate which resulted in a denser vegetation for the exposed continental shelf region.  相似文献   
942.
领海划界问题在民国时期取得了较大的进步.在内外因素的刺激下,中华民国政府经过几次讨论,于1931年颁布了三海里令,标志着中华民国领海制度的正式建立,这在中国领海制度发展史上具有里程碑的意义.除三海里令的颁布外,中华民国政府还颁布了其他一些领海法令,表明中华民国在领海制度建设方面取得了一定成绩.当然,民国政府在此问题上的不足也是显然的.  相似文献   
943.
Wang  ShiFeng  Zhang  WeiLin  Fang  XiaoMin  Dai  Shuang  Kempf  Oliver 《科学通报(英文版)》2008,53(9):1393-1400
The Zanda basin is one of the very important basins at the north slope of the Himalaya Range. Thus the study of the basin strata will provide critical information about the tectonic evolution of the Himalayan Orogenic Belt. 268 oriented block samples were collected in the 750-m-thick sections of the Zanda basin. The characteristic remanent magnetization (ChRM) was isolated that decays linearly to the origin between 500℃ and 690℃for most studied samples. An age range of 9.5-2.6 Ma was estimated from the correlation between our observed polarity column and the Geomagnetic Polarity Time Scale (GPTS). The age of the Zanda basin does not support the models that the South Tibetan Detach system (STDS) is one of the basin controlling faults. Given the sedimentological features in the basin and the tectonic features at the north edge of the basin, the Zanda basin was a half graben that was possibly controlled by the Karakorum fault on the northeast.  相似文献   
944.
在中国,日韩影视剧能够成功传播有着很多因素的影响,如中日和中韩外交关系的发展、日韩影视文本内含的儒家文化在中国的寻根等等。中国与日本、中国与韩国之间外交关系的发展、中日韩文化的接近性与差异性,分别构成了日韩影视剧能在中国成功开展跨国文化传播的政治与文化因素。  相似文献   
945.
吴艳 《科技信息》2008,(17):239-239
The development and wide spread of English language has led to the internationalization and localization of English language, during which English language is widely used in international communications by people with different mother tongues, in addition, English variations on different levels and local varieties have emerged. In consideration to the changes above, this paper aims to, firstly, examine the status of English language as an international language (EIL); secondly, explore the future of English language teaching (ELT) in China under a global context.  相似文献   
946.
Evaluation of a 3dVAR system for the South China Sea   总被引:4,自引:0,他引:4  
The authors evaluate a three-dimensional variational (3dVAR) system for the South China Sea (SCS) in this study. The assimilation method applied in the system takes into consideration error correlation along each ground track and uses recursive filter for optimiza- tion. Data from three R/V cruises during the spring and summer of 1998 and the summer of 2000 are used to evaluate the system. The root-mean-square error and bias are reduced significantly and when the altimeter data are assimilated, the distribution of the error is much closer to the Gaussian distribution. Precipitation and river discharge in the southwestern SCS are reproduced, and the variability of sea surface height is efficiently transferred to the subsurface. The 3dVAR system performs well for each of the three cruises, suggesting that it is steady for routine usage.  相似文献   
947.
Two fossil dragonflies from the Upper Jurassic to Lower Cretaceous Yixian Formation in Liutiaogou Village, Ningcheng County, Inner Mongolia, China are described and illustrated. They are assigned to two new genera and species, i.e., Sophoaeschna frigida gen. et sp. nov. and Falsisophoaeschna generalis gen. et sp. nov. within the family Gomphaeschnidae Tillyard & Fraser, 1940. This is the first report of Odonata from Yixian Formation in Inner Mongolia and the second record of fossil Gomphaeschnidae from China.  相似文献   
948.
东海表层沉积物中重金属集散特征及变化规律   总被引:2,自引:0,他引:2  
为研究重金属集散特征及在海洋沉积物中的变化规律,采用π定理建立准则,分别对表征重金属集散特征多因子中的中值粒径、细粒平均粒径及其含量、有机质和粘土含量做了数理统计与分析,建立多元集散控制方程,并运用最小二乘法求解方程中的相关系数.结果表明,该方程能够很好地表征海洋沉积物中重金属元素富集规律及其在海底环境中动态变化过程.  相似文献   
949.
美国对华传教工作始于1829年。美国来华传教士雅裨理和卫三畏分别于1830年与1833年来华。鸦片战争之前,由于清政府严格限制对外交往,来华传教士的活动范围受到限制,因此他们对中国的理解是比较肤浅的。在他们眼中,中国是个奇风异俗盛行的异教国度,是个等待西方“先进”文明与宗教拯救的民族。他们用文字记录了来华美国人对中国的最初印象,这些印象也成为此后美国人中国观的最初依据。  相似文献   
950.
新型农村合作医疗制度试点以来,取得了较大的成效,但也暴露了一些问题与矛盾。究其原因,最重要的是资金不足、筹资困难、筹资机制不健全。为此,应强化政府在新型农村合作医疗中的作用,合理构建政府、集体、社会、个人四方的筹资比例与机制。根据经济发展水平确定合理、动态的筹资标准,增加社会投入,建立多元化的筹资机制。逐渐实现城乡医疗一体化。每一出资主体内部,可以采取多种渠道与手段融资:政府可以开设合作医疗新税种、发行合作医疗彩票等;集体可以把现有的公共资源用于合作医疗。  相似文献   
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