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1.
MEN Wu ) WEI Hao ) and LIU Guangshan ) * ) College of Oceanography Environmental Science Xiamen University State Key Laboratory of Marine Environmental Science 《中国海洋大学学报(英文版)》2006,5(3):228-234
1Introduction Therearefourradiumisotopesinnature,ofwhich224Ra,226Raand228Rahavebeenwidelyinvestigated inmarineresearch,butthespecificactivityof223Rais toolowtobemeasured,therefore,itsapplicationsarelimited(Moore,1969;Broeckeretal.,1976;KuandLin,1976;Nozak… 相似文献
2.
During the 13th (1996–1997) and the 19th (2002–2003) Chinese National Antarctica Research Expeditions, we collected 60 discrete surface seawater samples along the
cruise from the Chanjiang River (Yangtze) estuary (30°59′S, 122°26′E) through Taiwan Strait, the South China Sea, and the
Eastern Indian Ocean to Prydz Bay, Antarctica (69°10′S, 74°30′E), and analyzed them for the 226Ra specific activity. The 226Ra specific activity of the Chanjiang River estuary surface water (3.15 Bq/m3) was found to be the highest among all the surface samples because of the desorption of 226Ra from riverine particles. Between Chanjiang River estuary and 40°S, 226Ra specific activity was found to be relatively uniform with a mean value of 1.07 Bq/m3 (n = 19, SD = 0.14), similar to that of the open ocean. From 40°S to 65°S, 226Ra specific activity increased intensively, then decreased moderately further southwards. Near the Antarctic shore, it increased
again, to 2.31 Bq/m3. This distribution was controlled by a combination of deep water upwelling, Southern Ocean fronts, water mixing and the continental
226Ra import. In Prydz Bay and the adjacent sea area, the mean 226Ra activity value was 2.26 Bq/m3 (n = 31, SD = 0.28), with a relatively higher value outside of the bay and low 226Ra activity value in the center of the bay. This was consistent with the topography and hydrological setting of the bay. In
addition, we extended the study area northward to the Arctic, by combining the published 226Ra dataset for surface water from the Bering Sea to the Japan Sea. We also discuss the 226Ra distribution of high latitude oceanic surface water and its mechanisms. 相似文献
3.
Geochemical studies of the U, Th, Ra, and40K in surface sediments of the China Sea and adjacent sea areas, the lower reaches of the Huanghe and Changjiang Rivers and
the estuaries of the Zhujiang and Rongjiang Rivers were carried out with a model 8180-4K multichannel Ge(Li)γ spectrometer
in 1981–1985. The mean values of U, Ra, Th,40K are about 2.11 ppm, 7.67×10−13g/g, 11.00 ppm, and 2.33 ppm respectively, in the China Sea, the Okinawa Trough, and the Changjiang and Huanghe River estuaries.
The distribution of the four isotopes is uniform in the above zone.
The contents of U and Th in the sediments of the Zhujiang and Rongjiang Rivers and the Fujian coast are 1–4 times higher than
those of the above zone and are related to the granite and radioactive ore present in the upper reaches of these rivers or
the adjacent mountains.
The distributions of U, Th, Ra, and40K are related to the physico-chemical property, redox state, geological type and grain size of the sediment, and biotic activity.
Contribution No. 1408, Institute of Oceanology, Academia Sinica, Qingdao. 相似文献
4.
马斌 《广东海洋大学学报》2008,28(2):104-107
在群舞创作中,舞蹈构图就是舞蹈演员与整个舞台空间的静止画面,"静止"是舞蹈构图的表现形式,"流动"是舞蹈调度的表现形式,作为舞蹈构图与构图的必要连接,在营造舞蹈情境和增强形式美上起到了补充作用。舞蹈调度是变换舞蹈构图的一种过程,舞蹈构图是调度过程的某一个停顿和结果。二者相辅相成,不断进行连接和变化,为表现舞蹈作品的主题,交代环境情节和塑造舞蹈形象而发挥其特有的作用。 相似文献
5.
《中国海洋湖沼学报》2018,(6)
The term ‘biological resources' here means a set of organisms that can be used by man directly or indirectly for consumption. They are involved in economic activities and represent an important part of a country's raw material potential. Many other organisms are also subject to rational use and protection. They can be associated with true resource species through interspecific relationships. The Caspian and Aral Seas are continental water bodies, giant saline lakes. Both categories of species are represented in the benthic and pelagic communities of the Caspian and Aral Seas and are involved in human economic activities. The most important biological resource of the Caspian Sea and the Aral Sea is their ichthyofauna, represented by both aboriginal species and species introduced by man in the 20 th century. Among invertebrates, the main biological resource of these saline lakes is the brine shrimp A rtemia. The physical state of the Caspian as a water body is relatively stable but its biological resources are very seriously af fected by irrational use. The Aral Sea since the second half of the 20 t h century has experienced catastrophic anthropogenic regression, which has led to the almost complete loss of its biological resources due to salinization. However, thanks to efficacious engineering measures, it has now become possible to preserve its northern part(Small Aral) and rehabilitate it, lowering the salinity to its former state. The result has been the restoration of its fish biological resources. In the southern part of Aral(Large Aral), which turned into a group of separated hypersaline reservoirs, the only resource species currently available is the brine shrimp A rtemia. The main environmental threats for biological resources of the future Caspian and Aral as well as potential solutions are considered. 相似文献
6.
Baochong Chen 《中国地理科学(英文版)》1994,4(3):242-251
陈宝冲ＴＨＥＣＨＡＮＧＥＯＦＴＨＥＧＥＮＥＲＡＬＦＯＲＭＡＮＤＴＨＥＴＲＡＮＳＰＯＲＴＯＦＴＨＥＷＡＴＥＲ，ＬＯＡＤＡＮＤＳＡＬＴＡＢＯＵＴＴＨＥＮＯＲＴＨ－ＢＲＡＮＣＨＯＦＴＨＥＣＨＡＮＧＪＩＡＮＧＲＩＶＥＲＭＯＵＴＨ￥ＣｈｅｎＢａｏｃｈｏｎｇ（Ｎ... 相似文献
7.
The Huanghe and Yongding rivers were formed before the early and middle Pliocene epoch. Then they became interior rivers because of the appearance of interior fault lake basins at the end of the Pliocene epoch. The interior flow period continued until the end of the early Pleistocene or the middle pf the Middle Pleistocene, and then they changed into the exterior rivers again till today. 相似文献
8.
王晓丽 《广东海洋大学学报》2007,27(5):73-76
中国浪漫主义文学的发展源远流长,从楚汉浪漫传统到晚明叛逆洪流,中国古代浪漫主义文学由幼稚走向成熟,也逐渐产生了和现代浪漫思潮相同的精神内涵,这就是强烈的自我意识和反叛意识;20世纪"五四"时期,在新文化运动的背景上发展出全新的、更为自由奔放的、波澜壮阔的现代浪漫主义文学巅峰。由于政治环境、文化氛围、文学传统等多种因素的影响,中国古代浪漫主义文学在广度、深度等方面都与现代浪漫主义文学存在明显差异。 相似文献
9.
ＴｈｅＳｏｎｇｈｕａＲｉｖｅｒ,ｏｎｅｏｆｔｈｅｍａｊｏｒｒｉｖｅｒｓｉｎＮｏｒｔｈｅａｓｔＣｈｉｎａ,ｈａｓｔｗｏｓｏｕｒｃｅｓ：ｔｈｅｎｏｒｔｈｓｏｕｒｃｅｉｓｔｈｅＮｅｎｊｉａｎｇＲｉｖｅｒａｎｄｔｈｅｓｏｕｔｈｓｏｕｒｃｅｉｓｔｈｅＳｅｃｏｎｄＳｏｎｇｈｕａＲｉｖｅｒ．ＴｈｅｔｒｕｎｋｓｔｒｅａｍｏｆｔｈｅＮｅｎｊｉａｎｇＲｉｖｅｒ,ｒｉｓｉｎｇａｔｔｈｅｓｏｕｔｈｅｒｎｆｏｏｔｏｆｔｈｅＹｉｌｅｈｕｌｉＭｏｕｎｔａｉｎ,ｉｓ１３７０ｋｍｌｏｎｇａｎｄｉｔｓｗａｔｅｒｓｈｅｄａｒｅａｉｓ… 相似文献
10.
《广东海洋大学学报》2016,(1)
为了使学员熟悉NAVTEX接收机的操作过程,全面理解NAVTEX系统的工作流程,提高实操训练效果,在C#环境下设计并实现了NAVTEX接收机和岸台工作仿真软件。NAVTEX接收机仿真软件仿真度高,能实现电文接收、设置岸台和电文拒收、电文打印、电文显示与管理等主要功能,基于UDP广播模式的岸台工作仿真软件能够模拟不同岸台的工作情况向局域网中广播电文。实验表明,岸台工作仿真软件能以较为合理的方式广播电文,两种仿真软件配合运行,有效地提高了实训效果。 相似文献
11.
理工科大学生人文素质教育状况是教育界关注的焦点之一。根据问卷调查的信息 ,对被试学生人文素质的三维结构进行了状态描述。在此基础上 ,通过对比分析和相关分析 ,探讨了理工科大学生人文素质较差的原因。最后给出了提高理工科大学生人文素质的几点建议 相似文献
12.
资源环境领域的信息化与本土化 总被引：2，自引：2，他引：0
陈述彭 《地球信息科学学报》2001,3(2):37-40
本文重点论述了资源环境领域的深层研究问题;同时提出用信息化推动现代化的观点,进而对地球信息科学与数字地球的战略进行了概要地分析。 相似文献
13.
基于NDVI时空序列数据,利用GLOPEM-CEVSA模型,本文估算并分析了长江源区1997-2012年植被覆盖度及植被净初级生产力时空变化特征,并在此基础上评估了生态工程实施前、后长江源区宏观生态状况变化。结果表明：工程实施后,长江源区宏观生态状况显著好转,植被覆盖度及植被净初级生产力明显增加。从多年平均值来看,工程实施后,植被覆盖度好转区域面积占植被区总面积的72.10%,净初级生产力增加区域面积占植被区总面积的73.82%;从变化趋势来看,植被覆盖度好转区域面积净增加13.02%,植被净初级生产力好转区域面积净增加24.62%。工程实施前后相比,各流域宏观生态状况恢复程度具有差异,其中楚玛尔河源头植被覆盖度上升最明显,通天河流域植被净初级生产力上升最明显。长江源区宏观生态状况的好转受益于气候的湿润化及生态工程的共同影响,若要全面有效改善仍需持续努力。 相似文献
14.
海原断裂东段至六盘山断裂西段GPS剖面地壳变形与应变积累分析 总被引：1，自引：0，他引：1
利用2004~2013年3期GPS速度场数据,从断裂两侧的水平挤压、拉张与走滑等3方面,对海原断裂东段至六盘山断裂西段GPS剖面变形与应变积累进行研究。结果表明：1)海原断裂东段与六盘山断裂西段在运动方式上具有较强的一致性;2)在近10 a时间尺度上,该活动断裂整体表现为以左旋走滑为主,兼顾压性变化的运动特征,在上、下盘的相对运动差异速率上,走滑方向上达到2.0~5.5 mm/a,断裂垂直方向上约为0.5~3.0 mm/a。 相似文献
15.
论述了现行油田勘探开发管理体制存在的问题指出现行管理体制已不能适应形势发展的需要。从提高油田勘探开发的整体经济效益出发，提出了加快勘探开发一体化改革的对策与建议。 相似文献
16.
刘刚 《广东海洋大学学报》2005,25(5):104-107
类书是一种特殊的文献编纂形式,它的真正起源应该是《皇览》。在文献聚集、文献利用、文学创作、帝王影响、文献编纂、学术思想等因素的共同作用下,类书得以产生与发展。类书是中国传统学术、文化与思想发展到魏晋南北朝时期的必然产物。 相似文献
17.
In this paper, by using ocean surface temperature data (COADS), the study is made of the characteristics of the monthly and annual changes of the SST in the tropical western Pacific and Indian Oceans, which have important influences on the climate change of the whole globe and the relation between ENSO(E1 Nino-Southern Oscillation) and the Antarctic ice area is also discussed. The result indicates that in the tropical western Pacific and the Indian Oceans the change of Sea Surface Temperture (SST) is conspicuous both monthly and armaully, and shows different change tendency between them. This result may be due to different relation in the vibration period of SST between the two Oceans. The better corresponding relationship is obvious in the annual change of SST in the tropical Indian Ocean with the occurrence El Nino and LaNlra. The change of the SST in the tropical western Pacific and the tropical Indian Oceans has a close relation to the Antarctic ice area, especially to the ice areas in the eastern-south Pole and Ross Sea, and its notable correlative relationship appears in 16 months when the SST of the tropical western Pacific and the Indian Oceans lag back the Antarctic ice area. 相似文献
18.
针对强非均质性碳酸盐岩储层微观孔喉结构差异所导致的孔隙度相似、渗透率和饱和度存在较大差异这一现象,开展
了孔喉结构的评价。基于孔隙度和渗透率,衍生出储层参数RQI 和RQF ;划分了压汞曲线的类型、分析了压汞曲线的形态,提取
了异于砂岩的压汞参数(SHg/pc)max;同时引入胶结指数m 值。以RQI 和RQF 为核心参数,建立各参数间的函数关系,以满足资
料丰度较弱的情况下孔喉结构的评价需求。另外,基于(SHg/pc)max与RQI 之间的相关性,在每个进汞压力测试点下,建立了SHg
与RQI 之间的函数关系,达到重构压汞曲线的目的。鉴于核磁T2 几何平均值与RQI 之间的相关性,可以利用T2几何平均值反
演储层的渗透率。分析碳酸盐岩储层孔喉结构和储层参数之间的关系,为完成孔喉结构的评价和储层参数的反演奠定了一定的
理论和实践基础。 相似文献
了孔喉结构的评价。基于孔隙度和渗透率,衍生出储层参数RQI 和RQF ;划分了压汞曲线的类型、分析了压汞曲线的形态,提取
了异于砂岩的压汞参数(SHg/pc)max;同时引入胶结指数m 值。以RQI 和RQF 为核心参数,建立各参数间的函数关系,以满足资
料丰度较弱的情况下孔喉结构的评价需求。另外,基于(SHg/pc)max与RQI 之间的相关性,在每个进汞压力测试点下,建立了SHg
与RQI 之间的函数关系,达到重构压汞曲线的目的。鉴于核磁T2 几何平均值与RQI 之间的相关性,可以利用T2几何平均值反
演储层的渗透率。分析碳酸盐岩储层孔喉结构和储层参数之间的关系,为完成孔喉结构的评价和储层参数的反演奠定了一定的
理论和实践基础。 相似文献
19.
为了研究青藏高原及周边地区波动E-P通量的分布与变化特征,利用1965～2010年NCEP/NCAR月平均再分析资料,计算了三维E-P通量,经过分析,得到如下主要结论：（1）对流层波动E-P通量的活动中心位于青藏高原南部.（2）波动E-P通量有着明显的季节变化.其中夏季的强度最大,且夏季与冬季相比,垂直分量正负值中心位置的分布几乎相反.从夏季到冬季,E-P通量垂直分量的正值中心逐渐向东北方向移动.（3）波动E-P通量的年代际变化也比较显著.从20世纪70年代中期到80年代前期,波动E-P通量变化平缓;80年代中期至90年代中期,变化很大,90年代中期达到最强,后又开始逐渐变缓. 相似文献
20.
深水油气勘探是近些年油气勘探取得重大发现的主要领域,我国已在琼东南盆地深水区中央峡谷体系中发现并成功开发了首个深水大气田——陵水17-2气田。为进一步扩大油气勘探成果,急需阐明中央峡谷源头区沉积特征及其油气勘探前景。基于在多口钻井约束下覆盖整个研究区的三维地震资料综合解释建立的等时地层格架,系统总结了中央峡谷体系的形成演化过程,及各演化阶段中央峡谷源头区的沉积体系类型、空间展布和沉积模式,进而结合研究区天然气成藏条件和成藏模式分析,讨论了中央峡谷源头区油气勘探前景。研究结果表明,中央峡谷源头区在黄流组发育了深水水道、陆架边缘三角洲和水道化扇等沉积体系,来源于印支地块、红河和海南岛等多物源区的沉积体系总体以重力流方式呈汇聚型向盆地深水区搬运,并最终汇聚于中央峡谷体系内。在中央峡谷源头区沉积的轴向水道、陆坡水道和水道化扇内发育了优质储层,因此,来自深部的天然气在具有以泥-流体底辟构造作为天然气输导通道的区域,有望聚集形成大型整装天然气藏。该研究成果不但丰富和完善了中央峡谷沉积体系的认识,而且对南海北部深水油气勘探具有重要实际价值。 相似文献