Clay mineral distribution in surface sediments of the South China Sea and its significance for in sediment sources and transport

Clay minerals of surface sediments in the South China Sea (SCS) are analyzed with X-ray diffraction, and their transport is explored with a grain size trend analysis (GSTA) model. Results show that clay mineral types in various sedimentary environments have different sediment sources and transport routes. Sediments in the northern SCS (north of 20°N) between the southwest of Taiwan Island and the outer mouth of the Pearl River have high contents of illite and chlorite, which are derived mainly from sediments on Taiwan Island and/or the Yangtze River. Sediments from the Pearl River are characterized by high kaolinite and low smectite content, and most are distributed in the area between the mouth of the Pearl River and northeast of Hainan Island and transported vertically from the continental shelf to the slope. Characterized by high illite content, sediments from Kalimantan Island are transported toward the Nansha Trough. Sediments from Luzon Island are related with volcanic materials, and are transported westwards according to smectite distribution. On the Sunda Shelf, sediments from the Mekong River are transported southeast in the north while sediments from the Indonesian islands are transported northward in the south. Ascertaining surface sediment sources and their transport routes will not only improve understanding of modern transportation and depositional processes, but also aid paleoenvironmental and paleoclimatic analysis of the SCS.     

用潜孔锤钻进技术施工蒙古国塔木察格水井

20世纪90年代以来,在基岩地区进行水文地质钻探大部分采用潜孔锤钻探工艺。这种工艺优点是效率高,而缺点是一次性投入较大,尤其是大口径潜孔锤钻进。     

影响遵义市秋粮产量的气象因子分析

分析水稻、玉米与生长期主要气象因子的相关性,并对农作物产量波动幅度大的重要年份进行详细分析,找出影响遵义市主要秋季作物的关键气象因子.     

遵义新一代天气雷达与713常规数字化天气雷达回波强度差异的分析

通过对遵义新一代天气雷达与713常规数字化天气雷达大量对比观测资料的分析,找出两种雷达在回波强度上出现差异的规律,并从信号处理原理的角度分析其产生差异的原因.     

De-eutrophication of effluent wastewater from fish aquaculture by using marine green alga Ulva pertusa

The de-eutrophication abilities and characteristics of Ulva pertusa, a marine green alga, were investigated in Qingdao Yihai Hatchery Center from spring to summer in 2005 by analyzing the dynamic changes in NH ₄ ⁺ , NO ₃ ^? , NO ₂ ^? as well as the total dissolved inorganic nitrogen (DIN). The results show that the effluent wastewater produced by fish aquaculture had typical eutrophication levels with an average of 34.3 μmol L^?1 DIN. This level far exceeded the level IV quality of the national seawater standard and could easily lead to phytoplankton blooms in nature if discarded with no treatment. The de-eutrophication abilities of U. pertusa varied greatly and depended mainly on the original eutrophic level the U. pertusa material was derived from. U. pertusa used to living in low DIN conditions had poor DIN removal abilities, while materials cultured in DIN-enriched seawater showed strong de-eutrophication abilities. In other words, the de-eutrophication ability of U. pertusa was evidently induced by high DIN levels. The de-eutrophication capacity of U. pertusa seemed to also be light dependent, because it was weaker in darkness than under illumination. However, no further improvement in the de-eutrophication capacity of U. pertusa was observed once the light intensity exceeded 300 μmol M² S^?1. Results of semi-continuous wastewater replacement experiments showed that U. pertusa permanently absorbed nutrients from eutrophicated wastewater at a mean rate of 299 mg/kg fresh weight per day (126 mg/kg DIN during the night, 173 mg/kg in daytime). Based on the above results, engineered de-eutrophication of wastewater by using a U. pertusa filter system seems feasible. The algal quantity required to purify all the eutrophicated outflow wastewater from the Qingdao Yihai Hatchery Center into oligotrophic level I clean seawater was also estimated using the daily discharged wastewater, the average DIN concentration released and the de-eutrophication capacity of U. pertusa.     

法国SPOT卫星

法国第一颗地球资源遥感卫星SPOT—1已于1986年2月22日从法国Guiana空间中心由阿里安娜火箭送入轨道。23日地面站已接收到第一批图象。卫星定位准确,其轨道参数为:近地点为818.269km(设计为816.6km);远地点为833.198km(设计为836.3km);轨道倾角为98.77°(设计为98.74°)。经过一系列检测,5月6日宣布SPO~T     

湿陷性黄土地区建筑地基处理方式浅议

对湿陷性黄土地区,尤其是位于城镇的建筑物地基基础如何处理,不仅与所处场地的地质有关,同时还要考虑其所处位置和周围环境的因素,工程造价也不容忽视．本文作者对定类工程的地基如何处理阐述了自己的看法．     

土地复垦整理开发项目实施准备关系进展快慢和质量好坏

土地复垦整理开发项目实施准备工作是项目实施工作中的一个重要环节,是确保项目顺利实施的重要手段.项目实施准备工作的充分与否不仅关系到项目实施的进展快慢和质量好坏,更关系到项目的效益和社会影响.     

水质监测中激光诱导荧光遥测技术的应用

激光诱导荧光(LIF)遥测是针对大面积水域富营养化状况进行原位、实时、快速测量的一种先进的监测技术。利用自行研制的水体污染LIF遥测系统对太湖水域进行了一次较为全面的测量,以测得的溶解有机物(DOM)荧光因子、瑞利散射因子和叶绿素a荧光因子分别代表各测量点的DOM浓度、浊度和叶绿素a浓度。同时以Skalar三维荧光成像仪测量各点DOM浓度,多参数水质分析仪测量浊度和叶绿素a浓度。对比分析了LIF遥测系统测量DOM荧光因子、瑞利散射因子和叶绿素a荧光因子与DOM浓度、浊度和叶绿素a浓度关系。结果表明LIF系统测得的DOM因子与三维荧光成像仪测量的DOM浓度值一致性较好(R=0.88733),而瑞利散射因子和叶绿素a荧光因子与多参数水质测量仪测得浊度值和叶绿素a浓度值线性相关性较差,相关系数分别为-0.39185和0.4552。对上述差异产生的可能原因进行了讨论,并阐述了LIF遥测技术在水质监测中的应用前景和潜在的应用限制。     

β-胡萝卜素在医学上的应用研究

β－胡萝卜素的最好天然产源是盐藻。盐藻是一种单细胞海藻，在适宜的环境条件下，它能大量累积β－胡萝卜素，最高可达干重的１０％左右，远远高于其他动植物体内的含量。关于盐藻养殖生物学、盐藻β－胡萝卜素生产技术以及其开发和应用（特别是在医学上的应用），目前是各国海洋学家研究的焦点之一，这方面的内容将另文阐述。为使读者对其应用有个明晰的了解，以期使人们对从海洋中开发这一重要资源的意义给予一定的关注，笔者仅就其在医学上的应用作一介绍。关于β－胡萝卜素在医学上的应用研究Ｐｅｔｏ等（１９８１）曾作过综述，近１０…