英国诺福克北部布尔河上游白垩和冰碛物含水层稳定同位素研究

<正> 前 言 最近两年中,我们研究了英国诺福克北部布尔河上游白垩系的白垩和上覆第四系冰碛物含水层中地下水的地球化学演变。为了进一步弄清水文地质条件和水文地球化学演变之间的关系,我们研究了该区地下水中的稳定同位素水文地球化学特征。 研究区位于东经1°—1°14′和北纬52°47′—54′(图1)面积为80平方公里。上白垩系的白垩层厚达450米,上复着第四系漂砾粘土和砂砾石冰碛物,其厚度达40—45米。      

Seasonal variations of exposure biomarkers, oxidative stress responses and cell damage in the clams, Tapes philippinarum, and mussels, Mytilus galloprovincialis, from Adriatic sea

This work investigated the natural variability of several biomarkers in Tapes philippinarum and Mytilus galloprovincialis, sampled from Northern Adriatic where these organisms are important sentinel species for future environmental impact assessment. Levels of metallothioneins, peroxisomal enzymes and acetylcholinesterase, showed a significant seasonality and marked differences between clams and mussels. Among antioxidant enzymes, catalase and GST decreased during the warmer period, the latter enzyme activity resulting particularly high in clams. The total oxyradical scavenging capacity toward peroxyl radicals decreased in mussels from winter to summer, indicating a prooxidant challenge due to higher seawater temperature and intensity of light irradiance. Lysosomal membrane stability did not exhibit significant seasonal variations, while some variations were observed for DNA damages. Overall results indicated a significant influence of seasonal variability on several biomarkers and species-specific differences which should be considered to discriminate the appearance of anthropogenic disturbance.     

Differential gene expression in the brain of Sebastiscus marmoratus in response to exposure to polychlorinated biphenyls (PCBs)

Effects of exposure to polychlorinated biphenyls (PCBs) on Sebastiscus marmoratus were investigated using a suppression subtractive hybridization method. A total of 108 gene sequences were identified as having the potential for being differentially expressed, and 45 could be identified with homologous database sequences. Functions with which they were associated included long-term potentiation and neurotransmitter release, neuroendocrine, mitosis and cell proliferation, energy-related metabolism, general metabolism, signal protein, hemopoiesis system, immune system, and structure. The expression of 17 of these genes was analyzed in the brain using real time fluorescent quantitative PCR. The present study provided a basis for studying the response of fish to PCB exposure and allowed the characterization of new potential neurotoxicol biomarkers of PCB contamination in seawater.     

Near-field dispersion of produced formation water (PFW) in the Adriatic Sea: an integrated numerical-chemical approach

Produced formation waters (PFWs), a by-product of both oil and gas extraction, are separated from hydrocarbons onboard oil platforms and then discharged into the sea through submarine outfalls. The dispersion of PFWs into the environment may have a potential impact on marine ecosystems. We reproduce the initial PFW-seawater mixing process by means of the UM3 model applied to offshore natural gas platforms currently active in the Northern Adriatic Sea (Mediterranean Sea). Chemical analyses lead to the identification of a chemical tracer (diethylene glycol) which enables us to follow the fate of PFWs into receiving waters. The numerical simulations are realized in different seasonal conditions using both measured oceanographic data and tracer concentrations. The numerical results show the spatial and temporal plume development in different stratification and ambient current conditions. The analytical approach measures concentrations of the diethylene glycol at a maximum sampling distance of 25 m. The results show a good agreement between field observations and model predictions in the near-field area. The integration of numerical results with chemical analyses also provides new insight to plan and optimize PFW monitoring and discharge.     

Efficient Approximate Method of Global Reliability Analysis for Offshore Platforms in the Ice Zone

Ice load is the dominative load in the design of offshore platforms in the ice zone, and the extreme ice load is the key factor that affects the safety of platforms. The present paper studies the statistical properties of the global resistance and the extreme responses of the jacket platforms in Bahai Bay, considering the randomness of ice load, dead load, steel elastic modulus, yield strength and structural member dimensions. Then, based on the above results, an efficient approximate method of the global reliability analysis for the offshore platforms is proposed, which converts the implicit nonlinear performance function in the conventional reliability analysis to linear explicit one. Finally, numerical examples of JZ20-2 MSW, JZ20-2NW and JZ20-2 MUQ offshore jacket platforms in the Bahai Bay demonstrate the satisfying efficiency, accuracy and applicability of the proposed method.     

对《中国国家自然地图集》的评价

1999年出版了中国国家自然地图集,它是反映中国自然、社会、历史、经济和文化系列国家地图集的一部分。该图集用中(2500册)英(1000册)文出版。中国国家自然地图集的工作在1956年由周恩来总理直接领导编制的“科学发展十二年规划”中就开始了。于1958年开始图集的设计工作。按设计要求,图集由四卷组成:即普通地图集、自然地图集、历史地图集、经济地图集。1965年出版了中华人民共和国自然地图集。普通地图集没有全部完成,于1969年出版了“中华人民共和国分省地图”。     

意大利威尼斯泻湖的自然特性和水体循环

威尼斯泻湖位于意大利北部,亚得里亚海边,是意大利最大的泻湖,水面面积约550 km2,平均水深1.1 m.入湖的陆地流域1 877 km2,每年流入泻湖淡水约900 Mm3.泻湖通过3个潮流通道与海洋交换水体和能量;因此,它传统上被分成3个水下盆地,每1个水下盆地对应一个潮流通道,一个潮周期内大量海水流进流出,总量相当于泻湖总容量的三分之一(Ga(c)i (c)等,2004).淡水通过许多支流注入泻湖,携大量的营养物质,这些物质主要沉积在北部泻湖地区(Zonta等,2001).最重要的支流位于泻湖的北面,这个区域2001年曾接受了超过总量50%的沉积物.同样,在泻湖区,有一个巨大的工厂,是意大利最重要的工业区之一.这些工业区是意大利热量、淡水和营养的重要来源.     

A Large Therizinosauroid （Dinosauria： Theropoda） from the Early Cretaceous of Northwestern China

We herein describe an associated partial postcranial skeleton of a theropod dinosaur discovered in the Lower Cretaceous Xinminpu Group of the Yujingzi Basin, in the Jiuquan area of Gausu Province, northwestern China. Features of its humerus, such as strongly expanded proximal and distal ends, a well developed medial tuberosity, distal condyles expressed on the humeral cranial surface, and a hypertrophied entepicondyle, definitively establish the therizinosauroid affinities of the specimen. It differs from other therizinosauroids in having a shallow, poorly demarcated glenoid fossa with a prominent rounded and striated tumescence on the dorsomedial surface of its scapular portion, and a pubis with a strongly concave cranial margin. It represents a new taxon, Suzhousaurus megatherioides gen. et sp. nov. Cladistic analysis recovers Suzhousaurus as the sister taxon of Nothronychus mckinleyi from the mid-Cretaceous of western North America; together, they are basal members of the Therizinosauroidea, more derived than the Early Cretaceous Falcarius and Beipiaosaurus but less derived than Alxasaurus and the Therizinosauridae. Along with ＂Nanshiungosaurus＂ bohlini from possibly coeval beds in the Mazongshan area of northern-most Gansu, Suzhousaurus represents one of the largest-known Early Cretaceous therizinosauroids, demonstrating that this clade attained considerable body size early in its evolutionary history.     

中国大陆地区对流层臭氧及痕量气体测量与气候变化的关系

中国和亚洲人口的增长、流动、城市的扩张以及工业的不断发展正影响着局地、区域甚至整个全球范围的空气质量、大气化学及气候系统。近年来，研究组一直在香港和中国大陆地区从事空气污染方面研究。本概述了中国大陆和香港地区对流层臭氧和痕量气体的变化情况，特别就东南亚地区生物体燃烧释放对对流层臭氧的影响及中国华南地区气候变化之间的关系作了讨论。     

全球定常波对大尺度地形的线性响应

本文应用一个定常态线性原始方程三维谱模式模拟出全球200 hPa定常波的结构特征。同时还考察了模式大气对大尺度地形的线性响应。