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991.
中国北部辽东湾表层沉积物中PAHs源解析和生态风险评价 总被引:1,自引:0,他引:1
ZHANG Yufeng WU Jinhao SONG Lun SONG Yonggang YANG Meng WANG Nianbin HAN Jiabo GUAN Daoming 《海洋学报(英文版)》2018,37(4):12-21
研究于2014年和2015年对辽东湾表层沉积物中16种多环芳烃(PAHs)的来源和生态风险状况进行了调查和评估。辽东湾表层沉积物中16种PAHs的含量范围为88.5-347 ng/g,高值区主要分布在辽东湾中部海域。对辽东湾各站位沉积物中多环芳烃的含量进行中聚类分析结果表明,辽东湾的采样站位可分为两类,一类站位主要分布在辽东湾沉积物中部海域,另一类站位主要分布在受陆源污染较为严重的近岸海域。辽东湾表层沉积物中PAHs的来源为燃烧源和石油源的混合来源,其中燃烧源为主要来源。萘、苊、苊烯、菲、二苯并[a,h]蒽可能偶尔会引发有害生物效应;辽东湾表层沉积物为低致癌风险;辽东湾中部海域表层沉积物中PAHs的生态风险和毒性污染水平高于辽东湾近岸海域。 相似文献
992.
Deep-water regions often have winds favorable for offshore wind turbines, and floating turbines currently show the greatest potential to exploit such winds. This work established proper scaling laws for model tests, which were then implemented in the construction of a model wind turbine with optimally designed blades. The aerodynamic, hydrodynamic, and elastic characteristics of the proposed new multi-column tension-leg-type floating wind turbine (WindStar TLP system) were explored in the wave tank testing of a 1:50 scale model at the State Key Laboratory of Ocean Engineering at Shanghai Jiao Tong University. Tests were conducted under conditions of still water, white noise waves, irregular waves, and combined wind, wave, and current loads. The results established the natural periods of the motion, damping, motion response amplitude operators, and tendon tensions of the WindStar TLP system under different environmental conditions, and thus could serve as a reference for further research. 相似文献
993.
994.
Phylogenetic relationship of Podocopida (Ostracoda:Podocopa) based on 18S ribosomal DNA sequences 总被引:1,自引:0,他引:1
1 IntroductionOstracodaisoneofthelargestgroupsoftheCrus-tacea (M artin and Davis, 2001), and the num bersofliving speciesofostracodesconsistof7 500. OneofthefrustratingaspectsforOstracodastudyisunstabili-tyofthehigherclassification status (Schram, 1986),w… 相似文献
995.
Tethys tectonic system has experienced a long-term evolution history, including multiple Wilson cycles; thus, it is an ideal target for analyzing plate tectonics and geodynamics. Tethyan evolution is typically characterized by a series of continental blocks that separated from the Gondwana in the Southern Hemisphere, drifted northward, and collided and accreted with Laurasia in the Northern Hemisphere. During this process, the successive opening and closing of multistage Tethys oceans(e.g.,Proto... 相似文献
996.
The Tethyan domain hosts the world’s most abundant hydrocarbon and Mississippi Valley-type(MVT) Pb-Zn resources. The relations among organic matter-rich sediments, MVT Pb-Zn mineralization, and the Tethyan tectonic evolution history are an important scientific issue. The data of paleogeographic reconstruction indicate that the Proto-, Paleo-, and NeoTethys oceans mainly lay in low latitude areas between 30°N and 45°S. The high temperature and precipitation and the lack of sea water overturning i... 相似文献
997.
Jianglin WANG Bao YANG Zhiyuan WANG Jürg LUTERBACHER Fredrik Charpentier LJUNGQVIST 《中国科学:地球科学(英文版)》2023,(5):1133-1146
Seasonal differences of temperature are crucial components of the Earth’s climate system.However,the relatively short observational record,especially for East Asia,has limited progress in understanding seasonal differences.In this study,we identify ten tree-ring chronologies separately correlated with local winter(December-February)temperatures and twelve different tree-ring chronologies separately correlated with summer(June-August)temperatures across East Asia.Using these discrete seasonal tre... 相似文献
998.
Chunhui TAO Zhikui GUO Jin LIANG Teng DING Weifang YANG Shili LIAO Ming CHEN Fei ZHOU Jie CHEN Nannan WANG Xiaohe LIU Jianping ZHOU 《中国科学:地球科学(英文版)》2023,(6):1212-1230
Polymetallic sulfides present in mid-ocean ridges(MORs) have become important strategic resources for humans, and a scientific metallogenic model is necessary for the investigation and exploration of these resources. Compared to fast-and slow-spreading MORs, ultraslow-spreading MORs show substantial differences in magma supply, tectonic activity, and oceanic crust structures. However, information on hydrothermal circulation and a metallogenic model related to sulfides along the ultraslow-spreadi... 相似文献
999.
Fahu CHEN Tingting XIE Yujie YANG Shengqian CHEN Feng CHEN Wei HUANG Jie CHEN 《中国科学:地球科学(英文版)》2023,(6):1241-1257
Since Shi et al. proposed that the climate in the drylands of Northwest China experienced a significant transition from a “warming and drying” trend to a “warming and wetting” trend in the 1980s, researchers have conducted numerous studies on the variations in precipitation and humidity in the region and even in arid Central Asia. In particular, the process of the “warming and wetting” trend by using obtained measurement data received much attention. However, there remain uncertainties about whe... 相似文献
1000.
Yan ZHAO Junlun LI Jian XU Huajian YAO Gaohua ZHU Hongfeng YANG Jinyu ZHANG Renqi LU 《中国科学:地球科学(英文版)》2023,(9):1960-1978
On September 5, 2022, a strong MS6.8 earthquake struck the Luding area in the Kangding-Moxi segment of the Xianshuihe fault zone, which is the northern boundary of the Sichuan-Yunnan rhombic block, causing considerable casualties. The Bamei-Kangding segment of the Xianshuihe fault zone, which is located only tens of kilometers away from the Luding earthquake, has hosted frequent moderate to strong earthquakes in history and is a dangerous earthquake-prone zone. Therefore, it is critical to inves... 相似文献