四川木里耳泽岩溶型金矿床形成条件和成矿机制

四川本里耳泽金-菱铁矿建造矿床,赋存于上二叠统海相碳酸盐岩层中,矿化受古岩溶的严格控制,组成矿石的基本矿物为菱铁矿,金不均匀地分布于菱铁矿矿体内。成矿溶液来自加热的循环地下水。成矿过程分为早阶段和中-晚阶段。成矿温度为156-210℃,成矿深度小于1km.成矿物质主要来自地层。成矿热液呈碱性和弱还原性,贫硫,含中等盐度。矿床形成时的地质构造环境较稳定。这是我国仅见的一种特殊金矿类型。     

郑州市大雾气候特点及一次个例分析

为了了解近20 a郑州市大雾的时空变化特征,根据1980-2005年郑州市大雾观测记录,统计分析了这一时期郑州市大雾的变化特点及产生大雾时的气象要素特征;并利用河南省地面和探空观测资料以及NCEP1°×1°再分析资料,从要素场、大气稳定度等方面,对2007年12月25-27日郑州市大雾形成原因进行了分析.结果表明:郑州市年雾日数呈下降趋势,每月都可以出现大雾,但12月最多,6月最少.降水后较大的相对湿度、稳定的大气层结以及近地层较小风速等是大雾形成的必要条件.     

杭州市区春节期间空气质量变化特点

分析近3年春节期间的空气质量资料，结果表明，杭州市区环境空气中PM10、SO2、NO2浓度较高，烟花爆竹燃放期间3种污染物出现高峰值，这与烟花爆竹燃放有关，PM25／PM10的比值高于年均值。     

海城7．3级地震前地震波动力学特征量的异常变化

本文给出对海城７．３级地震前地震波动力学特征量变化的一些最新研究结果。所研究的地震波包括体波（Ｐ，Ｓ波）、尾波和短周期地脉动三类。特征量有：体波与地脉动的波形时间线性度和空间线性度，平均半周期，频谱的峰值频率、拐角频率、相对频带宽度、相对频谱峰值、高频段的谱线斜率绝对值；尾波的时间熵、振幅比、持续时间、观测与计算持续时间差及其二阶差分、Ｑ＿ｃ值、反映介质混浊度与震源特性的系数ａ＿ｃ等。所得结果表明，三类地震波的上述动力学特征量大都在震前一至半年左右出现、有的在６－１０天乃至一天以内出现过不同形态的阶段性异常变化，因而可看作海城地震的中短期和临震的地震波前兆异常指标。     

SeaWiFS探测1997年闽南赤潮模型研究

在１９９７年秋季厦门附近海域微吓灌赤潮水体现场反射光谱测量的基础上,根据对ＳｅｓＷｉＦＳ可见光范围内各波段离水辐射率变化的分析,提出３、４、５波段离水辐射率差值（Ｌｗ５＋Ｌｗ３－２Ｌｗ４）〉Ｃ模型,用它计算了１９９７年１１月和１２月 潮时相的ＳｅａＷｉＦＳ图象,结果和赤潮发生的实际状况一致。     

Occurrence and environmental implications of magnetic iron sulfides in stiff muds from the continental shelf of the East China Sea

Magnetic properties were measured on 370 vibrocores obtained from the outer continental shelf of the East China Sea, with the aim of reconstructing environmental changes during the late Quaternary. High SIRM/χ values (>25 kA m⁻¹) found in stiff muds of late Pleistocene age suggest the presence of magnetic iron sulfides, especially greigite. Framboidal aggregates of greigite were further identified by scanning electron microscopy (SEM) and attached energy dispersive X-ray (EDAX) analyses, as well as powder X-ray diffraction (XRD) analyses of the magnetic separates. The occurrence of magnetic iron sulfides indicates the complex oxidation–reduction of the stiff muds, resulting from exposure and inundation during the last glacial maximum (LGM) and the post-glacial transgression, respectively.     

Multistatic estimation of high-frequency radar surface currents in the region of Toulon

Ocean Dynamics - The high-frequency radar coastal network in Toulon operates in multistatic mode for the monitoring of the ocean circulation in the Northwestern Mediterranean Sea. With 2...     

基于逆散射理论的介质参数与其地震响应的尺度对应关系研究

在反演过程中进行频带控制是多尺度反演的重要策略,但数据频率成分与要反演的参数之间的尺度对应关系尚不清晰。本文利用Kormendi论文中的测井曲线模型,基于逆散射理论将地下介质参数的扰动分解为0-0-9-11 Hz、9-11-18-22 Hz、18-22-36-44 Hz和36-44-80-90 Hz共4个尺度,并利用反射率正演模拟方法生成4个尺度扰动成分的地震响应。通过对比地下介质参数不同尺度的扰动及其地震响应的频带成分,发现二者在4个扰动尺度上均具有一致性,由此得出介质参数与其地震响应具有定量尺度对应关系的结论。据此从介质扰动的尺度概念引申出反射系数的尺度概念,从逆散射理论角度探讨实验结果的理论依据,并对其在指导反演分频参数选取及薄互层解释等方面的应用展望进行讨论。     

Relationship between structures of substituted indolic compounds and their degradation by marine anaerobic microorganisms

Degradation of selected indolic compounds including indole, 1-methylindole, 2-methylindole, and 3-methylindole was assessed under methanogenic and sulfate-reducing conditions using the serum-bottle anaerobic technique and marine sediment from Victoria Harbour, Hong Kong as an inoculum. Our results showed that indole degradation was achieved in 28 days by a methanogenic consortium and 35 days by a sulfate-reducing consortium. During degradation under both conditions, two intermediates were isolated, purified and identified as oxindole and isatin (indole-2,3-dione) suggesting that both methanogenic and sulfate-reducing bacteria use an identical degradation pathway. Degradation processes followed two steps of oxidation accomplished by hydroxylation and then dehydrogenation at 2- and then 3-position sequentially prior to the cleavage of the pyrrole ring between 2- and 3-positions. However, none of 1-methylindole or 2-methylindole was degraded under any conditions. 3-Methylindole (3-methyl-1H-indole, skatole) was transformed under methanogenic conditions and mineralized only under sulfate-reducing conditions. It is clear that methyl substitution on 1- or 2-position inhibits the initial attack by hydroxylation enzymes making them more persistent in the environment and posing longer toxic impact.