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31.
基于对子午链台站地震地磁前兆异常以及地球空间环境变化等研究方向的需求分析,利用网络、大数据、云计算等新技术,结合地震数据专家(DatistEQ)软件,设计子午链台站地磁指数报告自动产出系统。该系统通过低代码、敏捷式开发工作流程,连接不同功能节点,可以实现用户定制化、数据标准化、功能智能化的系统报告产出。通过本地或者云端一键流程化工作,将不同类型的数据发送到科研工作者或其他需求者,简化工作流程,优化数据处理,实现高效率产品产出。  相似文献   
32.
王娟  范迪 《海洋科学》2004,28(3):9-11
研究了海水浓度对生物接触氧化法处理废水的影响。结果表明,在淡水中添加海水超过35%时,生物接触氧化法去除废水的化学耗氧量(COD)的效果随着海水浓度的增加而降低.添加海水10%~25%时,COD的去除效果好,25%时COD最高总去除率可达87.8%.处理效果几乎与纯淡水的对照组(COD总去除率88.6%)等同。  相似文献   
33.
The Lakagígar eruption in Iceland during 1783 was followed by the severe winter of 1783/1784, which was characterised by low temperatures, frozen soils, ice-bound watercourses and high rates of snow accumulation across much of Europe. Sudden warming coupled with rainfall led to rapid snowmelt, resulting in a series of flooding phases across much of Europe. The first phase of flooding occurred in late December 1783–early January 1784 in England, France, the Low Countries and historical Hungary. The second phase at the turn of February–March 1784 was of greater extent, generated by the melting of an unusually large accumulation of snow and river ice, affecting catchments across France and Central Europe (where it is still considered as one of the most disastrous known floods), throughout the Danube catchment and in southeast Central Europe. The third and final phase of flooding occurred mainly in historical Hungary during late March and early April 1784. The different impacts and consequences of the above floods on both local and regional scales were reflected in the economic and societal responses, material damage and human losses. The winter of 1783/1784 can be considered as typical, if severe, for the Little Ice Age period across much of Europe.  相似文献   
34.
近十年来渤海湾围填海工程对渤海湾水交换的影响   总被引:2,自引:0,他引:2  
近十年来我国海岸带地区快速城市化,对土地的需求持续高涨,导致沿海地区围海造地现象愈演愈烈,海湾纳潮海域面积持续萎缩,对海湾的水交换带来了较大压力。为此,选取我国海岸带快速城市化的典型区域——渤海湾为例,研究近十年来渤海湾海岸带城市化对渤海湾水交换的影响。基于国际流行的MIKE3水动力模型耦合粒子追踪模块,应用2000年和2010年两个典型年份的渤海湾岸线资料,分别计算了2000年和2010年渤海湾环流系统及其驱动下的水质点运移规律和变化特征。研究将渤海湾划分为8个区块,定量化研究和对比了近十年来由于渤海湾持续围填海导致的海湾水存留时间和不同区块水交换能力的变化。结果表明,随着近十年来渤海湾沿岸快速城市化产生的岸线变化,导致湾内环流涡旋增多,决定湾内水交换的流场结构发生了显著变化,导致各区块的水交换能力和平均水存留时间不仅存在较大差异,而且发生了显著的变化。与2000年相比,2010年天津港、黄骅港和曹妃甸港区海域的平均水存留时间明显增加,水交换率下降,对区域水质的改善十分不利。  相似文献   
35.
地表风蚀物理过程风洞实验的初步研究   总被引:13,自引:5,他引:13  
本文介绍了研究地表风蚀物理过程中风洞实验的方法、内容及结果。实验表明:净风对土表的风蚀作用微弱,即使在遭到大风吹刮时,土表的结壳仍不易受到破坏。但在挟沙气流作用下,却能使土表结壳遭到破坏,风蚀发展异常迅速。自然形成的土表结壳、经风选被粗化的土表和长有草丛的地表均有抑制风蚀的保护作用。本实验在方法上虽属初步尝试,但能说明沙漠化物理过程的一般机制,并为防治按漠化的措施提供依据。  相似文献   
36.
朱英  王迪  赵宪富 《探矿工程》2012,39(5):71-74
在松江河石龙电站边坡加固工程中,采用小直径抗滑桩加锚杆的桩锚联合支护体系,替代单纯的大直径抗滑桩,解决了陡峭边坡大型设备无法使用问题。采用潜孔锤跟管钻进工艺,解决了人工填石层钻孔坍塌及不能用水做循环介质的问题。介绍了该边坡治理方案及其施工技术,对陡峭边坡灾害治理工程有实用参考价值。  相似文献   
37.
Out-of-equilibrium crystallization often produces complex compositional variability in minerals, generating zoning and other mixing phenomena. The appropriate microchemical characterization of the resulting out-of-equilibrium patterns is of critical importance in understanding the overall physical and chemical properties of the host crystalline phases. In this framework, the modeling of compositional changes assumes a fundamental role. However, when compositional data are used, their management with standard exploratory, statistical, graphical, and numerical tools may give misleading results attributable to the phenomenon of induced correlations. To avoid these problems, methods able to extract compositional data from their constrained space (the simplex) in order to apply standard statistics, have to be adopted. As an alternative, the use of tools having properties able to work in the simplex geometry has to be considered. A luzonite single crystal (ideal composition, Cu3AsS4) exhibiting concentric and sector zoning was studied using electron probe microanalysis in order to understand the mechanisms which give rise to chemical variability and conditions in the developing environment. Compositional variations were determined by collecting data along three different transects. The major and minor elements (Cu, As, S, Fe, Sb, Sn) were analyzed with the aim of characterizing their patterns of association in the crystal and, hence, crystal evolution. The whole covariance structure as well as the chemical relationships between the successive zones was investigated by means of compositional methods, considering both data transformation and the stay in the simplex approach. Results indicate that the crystal grew under quiescent conditions, where chemical control was primarily exercised by the mineral’s surface and only minor effects were due to changes in the composition of the surrounding fluid. Consequently, an oscillatory uptake of chemical components occurred in which a competition between famatinite-like (Cu3SbS4) and kuramite-like (Cu3SnS4) domains characterized the As-poor zones.  相似文献   
38.
采用木瓜蛋白酶水解金乌贼(Sepia esculenta)蛋白, 利用超滤、凝胶色谱和反相高效液相色谱从金乌贼蛋白水解物中制备抗氧化肽, 采用氨基酸序列分析仪和质谱(ESI-MS)确定抗氧化肽结构, 采用自由基清除实验和脂质过氧化抑制实验对多肽抗氧化能力进行评价。结果表明, 金乌贼蛋白经木瓜蛋白酶水解和分离纯化得到1个抗氧化肽(AEH-P3), 经氨基酸序列分析和质谱(ESI-MS)确定其结构为Ala-Pro-Pro-Glu-Asn-Gly-Met-Ala-Gln-Met (APPENGMAQM), 分子量为1045.22Da。体外抗氧化实验结果表明: AEH-P3对DPPH自由基(EC50 4.01mg/mL)、羟自由基(EC50 4.66mg/mL)、ABTS自由基(EC50 3.44mg/mL)和超氧阴离子自由基(EC50 6.03mg/mL)具有良好的清除作用, Ala-Pro-Pro-Glu-Asn-Gly-Met-Ala-Gln-Met (APPENGMAQM)亦显示出了良好的脂质过氧化抑制作用, 可以用于抗氧化相关的功能食品、药物或者食品添加剂。  相似文献   
39.
40.
Nisyros is a totally volcanic island located at the eastern limit of the quaternary calc-alkaline island arc system of the South Aegean Sea. Its age is rather young since K/Ar dating has given an age of 0.2 m.y. B.P. for one of the oldest outcropping products of this volcano. The volcanological evolution of Nisyros has tentatively been reconstructed as follows:
  1. after a period (from 3.0? to 0.2 m.y. B.P.) of submarine activity, evidenced by the presence of pillow-lavas and hyaloclastites, the volcano grew above sea level;
  2. effusive and explosive subaerial activity from different vents built up a complex stratovolcano, probably around 0.2 m.y. B. P.;
  3. at the end of an intense explosive activity (between 0.2 m.y. B.P. and Present) the top of the volcano collapsed forming a caldera which is still perfectly preserved. A post-caldera activity with eruptions of huge and viscous domes and lava flows of uniform composition, both inside and outside the caldera, concluded this stage of the volcano evolution;
  4. in historical times, spectacular phreatic explosion craters formed on the caldera floor;
  5. presently, a large area of the caldera floor is affected by a considerable hydrothermal activity. The hypothesis is formed that Nisyros volcano is not yet extinct.
Four small volcanic islets — Yali, Stronjili, Pakia and Perigusa — located a few miles on the North and West of Nisyros, although volcanologically independent of one another, are composed of products which are attributable, from the petrologic point of view, to the Nisyros magma. The volcanic rocks of Nisyros and of its neighbouring minor islands as well as the volcanics of the coeval volcanoes of the South Aegean Sea arc (Aegina, Milos, Santorini, etc.) belong to a typical orogenic calc-alkaline series (from basic andesites through andesites-dacites-rhyodacites to strongly silicic rhyolites) with normal K2O contents. The potassium contents of these rocks are compatible with the depth of 150 km (as inferred from geophysical data) for the inclined seismic zone underneath the active volcanic arc. The existence of a top-caldera as well as the occurrence of a huge amount of xenoliths (hornblende-rich cumulates and contact-metamorphic calcareous rock derivatives) suggest the presence of a magma chamber at a relatively shallow depth beneath the volcano. The rhyolitic obsidians of Yali can be considered as residual liquids from the Nisyros rhyodacites, thus representing the end-members of a fractionation process. Volcanological and petrological arguments are in favour of fractional crystallization as the most probable genetic process for the calc-alkaline differentiation series of Nisyros and of its neighbouring minor islands. However, the lack of any rock with a high alumina basalt composition makes it difficult to define exactly the nature of the parent magma. According to recent geophysical data, continental collision is already in progress at the Hellenic trench. Therefore, Nisyros and the other active volcanoes of the South Aegean Sea arc are approaching the senile stage. What would follow could be a transition to shoshonitic magmatism as a consequence of the deepening of the lithospheric slab under the Aegean microplate. The limited extension and the relatively short-lived calc-alkaline activity of the South Aegean Sea arc could be related to the particular geodynamic pattern of the Mediterranean area which is characterized by a microplates mosaic between the two converging African and Eurasian major plates.  相似文献   
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