Weathering of granite in Antarctica: I. Light penetration into rock and implications for rock weathering and endolithic communities

Where rocks are composed of translucent minerals, light penetrates the rock and, in so doing, impacts on the thermal conditions. Where minerals are not translucent all the heat transformation must be at the rock surface, and steep thermal gradients can occur. Where light does penetrate, a component of the incoming radiation is transformed to heat at differing depths within the rock, thereby decreasing the thermal gradient. Equally, light transmissive minerals facilitate endolithic communities, which can also play a role in rock weathering. The attribute of light transmission within rock and the impact this has on the resulting thermal conditions has not been considered within rock weathering studies. An attempt was made to monitor the amount of light penetrating the outer 2 mm of coarse granite under Antarctic summer conditions and to evaluate the thermal impact of this. It was found that the amount of light penetration at this site exceeded modeled or postulated values from biological studies and that it could significantly impact the thermal conditions within the outer shell of the rock. Although the resulting data highlighted a number of flaws in the experimental procedure, sufficient information was generated to provide the first assessment of the range of thermal responses due to light transmissive minerals in rock. Copyright © 2007 John Wiley & Sons, Ltd.     

Volatile Organic Compounds in Various Marine Organisms From the Southern North Sea

The concentration levels of 12 priority volatile organic compounds (VOCs) were determined in two species of vertebrates and four species of invertebrates from sampling stations in the southern North Sea, using a modified Tekmar LSC 2000 purge and trap system coupled to gas chromatograph–mass spectrometer (GC–MS). In general, concentration levels of VOCs found in this study were of the same order of magnitude as those previously reported in the literature. The concentrations of the chlorinated hydrocarbons (CHCs), with the exception of chloroform, tended to be lower than those of the monocyclic aromatic hydrocarbons (MAHs). The experimental data were statistically evaluated using both cluster analysis and principal component analysis (PCA). From the results of cluster analysis and PCA, no specific groups could be distinguished on the basis of geographical, temporal or biological parameters. However, based on the cluster analysis and the PCA, the VOCs could be divided into three groups, C₂-substituted benzenes, CHCs and benzene plus toluene. This division could be related to different types of sources. Finally, it was shown that organisms can be used to monitor the presence of VOCs in the marine environment and the observed concentrations levels were compared with proposed safety levels.     

粘土-MMH体系絮凝赤潮生物的动力学研究

根据分子碰撞理论和粘土表面改性对絮凝作用的影响,进行了粘土－ＭＭＨ体系絮凝沉降赤潮异弯藻（Ｈｅｔｅｒｏｓｉｇｍａ ａｋａｓｈｉｗｏ针藻）和新月菱形藻（Ｎｉｔｚｓｃｈｉａ ｃｌｏｔｅｒｉｕｍ）硅藻）表面电性,并对上述两种藻进行絮凝动力学实验。结果表明,一定颗粒度的粘土对赤潮异弯藻和新月菱表藻的絮凝速率随体系中ＭＭＨ比例的增大而呈不同程度的提高,对于粘土／ＭＭＨ比一定的混合体系,絮凝速率随粘土浓度的增     

舟山朱家尖海域污损生物的分布特征及其与环境因子的关系

根据2007年3月至2008年2月在舟山朱家尖蜈蚣客运码头进行的污损生物挂板试验,对该海域污损生物的种类组成、附着季节、生物量分布及生态特点进行了初步研究。结果表明:该海域共鉴定出污损生物85种,其中,藻类13种,腔肠动物13种,苔藓虫4种,多毛类12种,软体动物8种,甲壳类22种和其它13种。优势种为中胚花筒螅Tubularia mesembryanthemum、泥藤壶Balanus uliginosus、白脊藤壶Balanus albicostatus、僧帽牡蛎Saccostrea cucullata、近江牡蛎Crassostrea rivularis、马尔他钩虾Melita sp.、圆鳃麦杆虫Caprella acutifrons、长鳃麦杆虫C.equilibra和盘管虫Hydroides sp.。朱家尖海域全年都有污损生物繁殖附着,其中6—10月为附着盛期,表层和中层月板生物量的高峰值均出现在7月,最低值分别出现在2月和1月,表层月板全年附着总生物量为2 006.1g/m2,月平均生物量为167.18g/m2;中层月板全年附着总生物量为2 388.15g/m2,月平均生物量为199.01g/m2;季度板污损生物生物量按高低依次为:夏季>秋季>春季>冬季;上半年板污损生物的生物量>下半年板。在垂直分布上,除季度板外,其它试板的生物量和附着密度均为中层>表层。根据污损生物的生态习性、分布特征及对盐度的适应,可将舟山朱家尖海域主要污损生物定义为河口低盐种。水温是影响调查海域污损生物分布的主要因素,水体盐度则对朱家尖海域污损生物的种类及指标种分布具有决定性作用。     

发展旅游业要避免的陷阱--"柠檬问题"

文章首先介绍了旅游业的一些基本情况,然后着重分析了在产品信息不对称的情况下,市场上出现“柠檬问题”的内在机制,通过对旅游业的特性分析,文章认为旅游业中存在发生“柠檬问题”的可能性,并从理论和实践的角度论证了如何规避旅游业中的“柠檬问题”,最后,文章阐说了解决“柠檬问题”对地区旅游以及区域经济发展的意义。     

Contamination of harbor sediments in the eastern Gulf of Finland (Neva Bay), Baltic Sea

 The areal distribution of oil products and various trace metals have been studied in bottom surface deposits from the harbors of Neva Bay. The data of contents were normalized to natural background concentrations. Also the size and biomass of benthos groups were analyzed. The results show clearly that industrial discharges have elevated levels of contamination in the sediments. Few efficient measures against environmental contamination have been taken. The sediments contain very high concentrations of oil products and such heavy metals as Hg, Pb, Cu, and Zn. The benthic organisms most sensitive to heavy metal contamination are Chironomidae. The dredging and dumping of the contaminated deposits can lead to secondary contamination of the Gulf of Finland and the Baltic proper. Received: 18 November 1996 · Accepted: 17 March 1997     

Exact linearization of non-planar intermediary orbits in the satellite theory

In this paper we consider the reduction of the equations of motion for non-planar perturbed two body problems into linear form. It is seen that this can be easily accomplished for any element of the class of radial intermediaries to the satellite problem proposed by Deprit in 1981, since they have a functional dependence suitable for linearization. The transformation is worked out by using an adequate set of redundant variables. Four harmonic oscillators are obtained, of which two are coupled through gyroscopic terms. Their constant frequencies contain the secular contribution of the main problem of artificial satellite theory up to the order of the considered intermediary. Therefore, this result may well be interesting in relation to the study and prediction of accurate long-term solutions to satellite problems.     

泛华北区石炭系、二叠系内部的重要地质演化转折

对华北地台及邻近区域内重要露头及钻井剖面的石炭系及二叠系展开新一轮系统研究，发现在这一套地层中存在两个重要的地质演化过程转折，即下石炭统、上石炭统之间及中二叠统、上二叠统之间（相当于华北新分层系统上石盒子组与平顶山组之间）存在两个地质演化过程转折。后一转折更为显著：转折面之下，气候背景干热化特征突出，沉积序列呈显著水退趋势，盆地萎缩，石膏质或红色泥质岩系发育，层系沉积缺失或剥蚀缺失现象严重，特化生物类型发育；转折面之上，气候背景呈现降温趋势，沉积序列呈显著水进趋势，盆地覆盖范围急剧扩展，沉积层系在区域上呈大规模超覆，与强烈引张断陷活动相关的砂砾岩发育，暗色泥质岩层系随之出现，特化生物类型迅速衰退。从地球表层系统演化及盆地发育角度考虑，后一转折面在地史占有更为突出的地位，应受到充分关注。     

滨海核电冷源取水区风险生物的分类及特征分析

近年来由海洋生物入侵造成的核电冷源安全事件频发,表明冷源安全已成为核电安全与可靠的重要影响因素,受到社会高度关注。本文对国内外发生的主要冷源安全事件进行统计分析,归纳总结冷源致灾生物的分类特征及其致灾机制,探讨致灾生物的筛选及分级预警标准,解析相关的探测技术、预警手段及处置方法,提出致灾生物研究中亟待解决的关键科学与技术问题,以期为更好应对解决滨海核电冷源安全问题提供参考与理论依据。     

深渊生物资源取样装备技术体系研究

针对深渊生物资源研究的需求，自主研发了用于全海深深度的深渊沉积物、水体和宏生物的保压取样装置，深渊沉积物保压转移装置，深渊微生物原位过滤及保存装置和高压培养高压酶学测定装置。在深海模拟环境验证了取样装置在万米深度下的工作性能。相关装置在“探索一号”科考船的TS15、TS21-1和TS21-2大洋科考航次中，搭载“奋斗者”号载人潜器、“2号”深渊着陆器、“原位实验”号着陆器于西菲律宾盆区和马里亚纳海沟进行了海上试验，成功获取了万米深度沉积物、水体和宏生物保压样品以及微生物原位过滤滤膜；成功进行了沉积物保压样品的保压转移试验。初步形成了深渊海域生物资源取样的装备技术体系，为深渊海底生物和基因资源开发，深渊生命过程等科学研究提供技术手段。