黄河三角洲水冰险情预警信息系统设计与分析应用探讨

本文探讨了黄河三角洲地区水冰灾情信息系统的建立方法及其应用问题。介绍了该系统的设计原则,数据结构,建立方法和程序,并对其应用进行了分析研究。该方法也适用于其它区域。     

滇池银鱼资源变动的生态学分析

以银鱼移植滇池后资源变动的状况为例分析了持续处于高密度状态下的r—选择型种群其密度对个体生长及生物量的影响、种群动态变化之间的关系，并对滇池银鱼衰退的主要原因进行了探讨。     

3-D Shoreline Extraction from IKONOS Satellite Imagery

Shorelines are recognized as unique features on Earth. They have valuable properties for a diverse user community. At present, photogrammetry is the most popular technique used to capture a shoreline. With improved resolution and accuracy, commercial high-resolution satellite imagery is demonstrating a great potential in the photogrammetry application domain. One example is the utilization of IKONOS satellite imagery in shoreline extraction. IKONOS panchromatic imagery has a resolution of approximately one meter as well as the capabilities of stereo imaging. This article presents the results of an experiment in which we attempted to improve IKONOS Rational Functions (RF) for a better ground accuracy and to employ the improved RF for 3-D shoreline extraction using 1-meter panchromatic stereo images in a Lake Erie coastal area. Two approaches were investigated. One was to rectify the ground coordinates derived from vendor-provided RF coefficients using ground control points (GCPs). The other was to refine the RF coefficients using the GCPs. We compare the results from these two approaches. An assessment of the shoreline extracted from IKONOS images compared with the existing shoreline is also conducted to demonstrate the potential of the IKONOS imagery for shoreline mapping.     

海藻多糖微量元素配合物的生物活性初步研究

用广东沿海盛产的半叶马尾藻Ｓａｒｇａｓｓｕｍｈｅｍｉｐｈｙｌｌｕｍ为原料提取多糖，与Ｆｅ（３＋），Ｚｎ（２＋）等微量元素进行反应，形成能溶于水的海藻多糖配合物。分别以剂量为３００ｍｇ·ｋｇ（－１）的海藻多糖配合物饲喂ＮＩＨ系小鼠７－１５ｄ。结果发现，该多糖配合物能提高小鼠的血红蛋白和红细胞数量。其中，以Ｆｅ（３＋）海藻多糖配合物效果最显著。观察各种免疫指标，发现海藻多糖和海藻多糖微量元素配合物都能提高小鼠的免疫指标。海藻多糖微量元素配合物的效果比海藻多糖好。结果提示，微量元素参与了机体的免疫活动，并提高了免疫活性。     

Glutathione-mediated chlorothalonil detoxification in channel catfish gills

Maintenance of the glutathione (GSH) pathway is critical in guarding against the toxic effects of a variety of pollutants. However, despite their importance as an initial line of defense against waterborne toxicants, little is known regarding the role of fish gills in GSH-mediated xenobiotic metabolism. In these studies, the role of channel catfish gills in the detoxification of 2,4,5,6-tetrachloroisophthalonitrile (chlorothalonil), an electrophilic fungicide, was examined. Chlorothalonil was metabolized in vitro by gill cytosolic and microsomal glutathione S-transferases (GSTs). Chlorothalonil metabolism by cytosolic fructions was reduced markedly when GSH was omitted from reaction mixtures. Microsomal metabolism of chlorothalonil did not occur in the absence of GSH and in the presence of an NADPH-regenerating system lacking GSH. Channel catfish exposed in vivo to chlorothalonil had increased gill GSH and cysteine concentrations after 72 h exposure, and increased gill gamma-glutamylcysteine synthetase (GCS) activity at 144 h of exposure. Our results show that the gills play an important role in the metabolism and detoxification of chlorothalonil in the channel catfish. Catfish can maintain elevated gill GSH concentrations in the presence of chlorothalonil by increasing gill cysteine concentrations.     

深海能源土含气储层力学特性三轴试验研究

为研究深海能源土在负压开采过程中含气储层的力学特性,基于含气土赋存理论,提出一种能够控制含气量及气泡大小的制样方法,通过GDS标准应力路径三轴试验系统,开展深海能源土含气储层的固结排水试验研究,分析深海能源土在不同黏土含量及不同含气量下的力学响应规律。研究结果表明：围压变化对深海能源土含气储层的抗剪强度峰值大小影响显著,围压越大抗剪强度峰值越高;黏土含量是决定应力应变曲线变化趋势的关键影响因素,黏土含量越高试样抗剪强度越低,试样抵抗应变软化效应的能力越强;含气土比饱和土体承载能力更低,且承载能力随含气量的增大呈衰减趋势;黏土含量和含气量是深海能源土含气储层抗剪强度指标的重要影响因素,黏土含量、含气量越高,土体自身的总抗剪强度值越低。     

海洋浅表层天然气水合物资源评价

浅表层天然气水合物具有埋藏浅、厚度大、纯度高等特点。现有的评价方法多针对于具有明显BSR反射特征的中深层天然气水合物,而对浅表层天然气水合物的相关研究鲜有发表。本研究通过对国内外浅表层水合物发育区广泛调研,以浅表层水合物的形成机理为基础,探究水合物资源评价方法的选择;以水合物空间展布规律为参考,明确评价范围界定条件;以综合指示特征为参考,分析评价参数的选取依据。并在此基础上,与中深层天然气水合物进行对比,提出浅表层天然气水合物资源刻度区选取及解剖的初步建议,引出评价中存在的问题,梳理出浅表层天然气水合物的资源评价方法的关键问题。     

海洋生物抗菌肽在枯草杆菌BS168中的高效表达

为了实现基因工程高效制备tachyplesin Ⅰ,采用tachyplesin Ⅰ基因串联表达的方法,以穿梭表达载体pSBPTQ为表达载体,通过RT-PCR扩增tachyplesin Ⅰ基因(tac)和采用直接退火的方法合成tachyplesin Ⅰ串联基因(2tac),构建重组表达载体pSBPTQ-TAC和pSBPT...     

南海北部陆缘区中特提斯构造演化研究

通过对南海及周边地区特提斯构造遗迹的综合分析，并与东亚、东南亚地区特提斯构造对比，认为南海北部陆缘区存在可以进行东、西向对比的中特提斯构造。相应的中特提斯洋因北巴拉望－礼乐－南沙地块与华南大陆边缘在白垩纪中期的碰撞而关闭。南海北部陆缘区中特提斯构造向西可以与加里曼丹的Metratus缝合线和苏门答腊的Woyla缝合线对比，向东经台湾海峡、琉球群岛与日本佐用带对比。南海北部陆缘区中特提斯构造的确认对正确解释南海北部陆缘区地壳结构在东西向和南北向的差异、重新认识华南陆域内地质构造演化以及对南海北部陆缘区油气资源勘探均具重要意义。     

南海热流特征及其构造意义

根据南海 592个热流数据 ,为克服热流站位分布不均及局部异常热流的影响 ,结合各单元的地质史及其地壳厚度等资料对研究区热流特征进行了详细分析。结果表明 ,具拉张背景的区域如北部陆缘、湄公盆地以及北巴拉望盆地具有中等偏高热流 ;海沟区热流相对较低 ,东部海沟区除台西南盆地外均为低热流区 ,而南部边缘东段古海沟区处于热恢复中 ;南部边缘西区因边界断裂的扭张及深部热源的异常补给而具高热流 ;属于剪切断裂带的西部陆缘也具高热流特征 ;中沙—西沙地区热流中等偏高 ,并由NW往SE方向增加 ,而南沙地区热流较低 ,约为 60mW·m- 2 ;海盆的热流基本满足随洋壳年龄增加而降低的规律 ,东部次海盆实测热流与理论预测基本一致 ,而西南次海盆实测热流普遍低于预测值 ;在南海北部下陆坡区识别出一条高热流带 ,该带与前人给出的海盆北缘断裂带位置基本一致。研究区不同区域地热特征直接或间接地受控于其所处的构造环境。据此 ,给出了研究区的热流趋势图。