Geographical, seasonal and interannual variations of air-sea CO₂ exchange in the subtropical Pacific surface waters during 1983–1988     

C. S. WONG  Y.-H. CHAN  J. S. PAGE 《Tellus. Series B, Chemical and physical meteorology》1995,47(4):431-446

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The Implications of Crustal Kinematics Associated with the 2008 M=8 Wenchuan Earthquake by Land-based Gravity Surveys     

TUNG Sui Jay  CHAN Lung Sang  ZHU Jieshou  Timothy MASTERLARK 《地质学报》2013,87(Z1):292-292

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雪卡毒素及其产毒底栖甲藻的研究现状与展望          下载免费PDF全文

陈荔  吴佳俊  王鹏斌 《海洋科学进展》2022,40(4):581-593

雪卡毒素（Ciguatoxins,CTXs）是一种高度氧化的环状聚醚梯类毒素,主要由冈比亚藻（Gambierdiscus）和福氏藻（Fukuyoa）两个属的底栖甲藻的一些产毒种类的株系产生。毒素通过海洋食物链在珊瑚礁鱼类中进行生物转化和积累,可引起常见的非细菌性海产中毒——雪卡毒素中毒（Ciguatera Poisoning,CP）,食用被CTXs污染的鱼类会引起消费者产生胃肠道、心血管、神经方面的症状甚至导致死亡,但目前雪卡毒素中毒在全球引发的关注度与重视度不足。然而受全球气候变化和人类活动的影响,底栖甲藻在全球扩张趋势明显,特别是在亚洲地区,雪卡毒素中毒事件频繁爆发,雪卡毒素中毒对人类健康和生态系统健康构成了重大威胁。本文重点综述了产雪卡毒素底栖甲藻的种类多样性、化学多样性、生理生态学研究、以及毒素的生物合成机制与生物转化和累积方面的研究,并探讨了亚洲地区作为雪卡毒素潜在的爆发地点未来值得研究的领域以更好地保障亚洲海域的生态安全及居民健康。  相似文献   

Preface to the Special Issue: Climate Change and Variability of Tropical Cyclone Activity     

Liguang WU  Bin WANG  Johnny CLCHAN  Kyung-Ja HA  Il-Ju MOON  Jun MATSUMOTO  Zhemin TAN  Ke FAN 《大气科学进展》2022,39(2):203-204

Tropical cyclones(TCs) are one of the most destructive natural phenomena on Earth in terms of human-life and economic losses. It is currently a matter of prodigious public and scientific interest how TC activity has changed and will change in a warming climate. This special issue focuses on a challenging subject raised in the Intergovernmental Panel on Climate Change(IPCC) report and numerous research papers.  相似文献   

Amino acid analyses of type 3 chondrites Colony,Ornans, Chainpur,and Bishunpur     

H.‐S. CHAN  Zita MARTINS  Mark A. SEPHTON 《Meteoritics & planetary science》2012,47(9):1502-1516

Abstract– The CO3s Colony and Ornans and LL3s Chainpur and Bishunpur were analyzed for the first time for amino acids using gas chromatography–mass spectrometry (GC‐MS). Type 3 chondrites have relatively unaltered metamorphic and petrological histories. Chainpur was the most amino acid rich of the four type 3 chondrites with a total amino acid abundance of 3330 parts per billion (ppb). The other type 3 chondrites had total amino acid abundances that ranged from 660 to 1110 ppb. A d /l ratio of <0.7 for all proteic amino acids suggests at least some amino acid terrestrial contamination. However, a small fraction of indigenous extraterrestrial amino acids cannot be excluded because of the presence of the nonprotein amino acid α‐aminoisobutyric acid (α‐AIB), and unusually high relative abundances (to glycine) of β‐alanine and γ‐ABA. The comparisons between the free and total amino acid contents of the samples also indicate a low free/total amino acid ratio (ranging from about 1:4 in CO chondrites to about 1:50 in Chainpur), which indicate that amino acids are present mainly in the bound form and were made detectable after acid hydrolysis.  相似文献   

激光雷达地形资料用于河道输沙的研究     

谢有忠  詹瑜璋  胡植庆  林朝宗 《遥感学报》2013,17(1):193-209

中国台湾地区位处亚热带地区,夏季受台风暴雨侵袭,加上位处板块运动活跃处,造成地形变化较大,尤其在台风暴雨后河道地形都会产生很大的变化;目前航空激光雷达地形数据,分辨率较高、精度、便利性,并可以滤除建筑物与树木遮蔽,还原原始地面形貌,符合地质与地形分析研究的需要。2008年兰阳溪地区经历海鸥(KALMAEGI)、凤凰(FUNG-WONG)、森拉克(SINLAKU)、蔷薇(JANGMI)等4次重大台风事件,河床地形变化甚剧,因此本研究利用两次航空激光雷达测量地形数据,分析比较台风前后河床地形以及河道输沙的变化。研究成果首次展示空载激光雷达系统,在大流域面积测量河道地形应用效果显著,于台风季节前后产制不同时期的数值地形数据,并应用高程差值的地形计量方法,计算在台风季节前后河道地形的变化,研究结果显示空载激光雷达高解析数值地形模型数据,应用在河道地形变迁与沉积物体积变化量计算,可以得到极佳的成果。  相似文献   

在EBEX-2000实验资料中湍流耗散率、长度尺度和结构参数特征   总被引：1，自引：1，他引：0  

刘树华  刘和平  李洁  梁福明  王建华  Johnny C. L. CHAN  Andrew Y. S. CHENG  胡非  刘辉志 《大气科学》2005,29(3):475-481

采用2000年8月在美国加州棉花地两个高度上应用超声三分量仪、快速响应温度和湿度仪进行的EBEX-2000 (International Energy Balance Experiment, 2000, 简称EBEX-2000) 风速三分量、温度和湿度湍流实验观测数据, 计算分析了在不同稳定度下的湍流能量和热量耗散率和湍流结构参数特征.并与Kansas和长白山原始森林湍流实验得到的结果进行了比较, 得到了一些湍流特征量在不同下垫面情况下的一些有意义的特征.  相似文献   

The origin and emplacement of the Lajishankou ophiolite complex in the South Qilian belt: evidences from geological mapping     

CHAN Lung Sang 《《地质学报》英文版》2019,93(Z2):9-9

Many ophiolite complexes like those of Oman and New Caledonia represent fragments of ancient oceanic crust and upper mantle generated at supra‐subduction zone environments and have been obducted onto the adjacent rifted continental margin together with the accretionary complexes and intra‐oceanic arcs. The Lajishan ophiolite complexes in the Qilian orogenic belt along the NE edge of the Tibet‐Qinghai Plateau are one of several ophiolites situated to the south of the Central Qilian block. Our geological mapping and petrological investigations suggest that the Lajishankou ophiolite complex consists of serpentinite, wehrlite, pyroxenite, gabbro, dolerite, and pillow and massive basalts that occur in a series of elongate fault‐bounded slices. An accretionary complex composed mainly of basalt, radiolarian chert, sandstone, mudstone, and mélange lies structurally beneath the ophiolite complex. The Lajishankou ophiolite complex and accretionary complex were emplaced onto the Qingshipo Formation of the Central Qilian block which shows features typical of turbidites deposited in a deep‐water environment of passive continental margin. Our geochemical and geochronological studies indicate that the mafic rocks in the Lajishankou ophiolite complex can be categorized into three distinct groups: massive island arc tholeiites, 509 Ma back‐arc dolerite dykes, and 491 Ma pillow basaltic and dolerite slices that are of seamount origin in a back‐arc basin. The ophiolite and accretionary complex constitute a Cambrian‐early Ordovician trench‐arc system within the South Qilian belt during the early Paleozoic southward subduction of the South Qilian Ocean prior to Early Ordovician obduction of this system onto the Central Qilian block.  相似文献   

东南亚地区生物体燃烧影响华南地区对流层臭氧垂直分布的个例分析   总被引：8，自引：0，他引：8       下载免费PDF全文

郑永光  朱佩君  陈尊裕  陈鲁言  崔宏  郑向东  赵琼  秦瑜 《地球物理学报》2004,47(5):767-775

2001年3月7日与8日在香港与昆明用电化学臭氧探空仪探测到了对流层低层异常的高浓度臭氧分布. 本文使用NCEP（美国环境预报中心）分析资料、中尺度数值模式MM5模拟的大气环流数据、卫星观测的东南亚地区的生物体燃烧状况、气溶胶指数等资料,分析了这段时间的天气形势、大气环流、空气的后向轨迹以及生物体燃烧产生的烟尘的轨迹,结果发现高浓度的臭氧空气来源于有生物体燃烧的中南半岛地区. 燃烧烟尘的轨迹还表明生物体燃烧地区的下风方的对流层低层臭氧的分布会受到上游地区生物体燃烧产物的影响.  相似文献   

西秦岭金属成矿的准对称特征及找矿意义   总被引：4，自引：0，他引：4       下载免费PDF全文

赵彦庆  李永琴  陈国忠 《甘肃地质》2004,13(2):85-89

西秦岭从中晚泥盆世开始,秦岭微板块由于勉略带的裂解扩张而进入独立演化,其构造演化、构造环境、沉积建造、岩浆活动和成矿作用等具有南北基本对应的准对称特征。本文通过对比分析,认为白龙江构造带是热液再造型铅锌矿的有利成矿带,而北部夏河—礼县成矿带南缘则是金的找矿远景区。  相似文献