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From China to Russia,Tan-Lu fault system stretches for thousands of kilometers,towards NE 30°.The authors have collected more than ten magnetotelluric profile that China and Russia have carried out,in the studied area of the Tan-Lu fault’s northern section,and have analyzed electrical characteristics of the relevant profiles.Deriving the following conclusions:(1)Jiamusi-Bureya plots,etc.,demonstrate the high resistance of Kernel;(2)Fold belt attributed to the land showed high and low resistance stitching,associated with not only terrane accretion,but also upper mantle upwelling;below the sedimentary basin,the resistivity of the upper mantle is lower and closer to the surface comparing with the adjacent area(100-150);(3)In the system of Tan-Lu fracture,Yishu and Dunmi fracture,etc.are expressed as vertical low-resistivity zone;(4)There may exist subducted old-fashioned piece under Jiamusi and Bureya plots.  相似文献   
704.
This paper presents the recent progress in our project of estimating near real-time electric fields and currents in the ionosphere through our computer system called the Geospace Environment Data Analysis System (GEDAS). We show a new technique in which data from ground magnetometers are collected by the system and used as input for the KRM and AMIE programs to calculate the distribution of ionospheric electric fields and currents, as well as of other ionospheric parameters, such as electric potential patterns. One of the goals of this project is to specify ionospheric processes. Examples of the near real-time calculation and the data flow of our scheme are presented.  相似文献   
705.
Three hundred and six coal samples were taken from main coal mines of twenty-six provinces,autonomous regions,and municipalities in China,according to the resource distribution and coal-forming periods as well as the coal ranks and coal yields.Nitrogen was determined by using the Kjeldahl method at U.S.Geological Survey(USGS),which exhibit a normal frequency distribution.The nitrogen contents of over 90% Chinese coal vary from 0.52% to 1.41% and the average nitrogen content is recommended to be 0.98%.Nitrogen in coal exists primarily in organic form.There is a slight positive relationship between nitrogen content and coal ranking.  相似文献   
706.
Aaron  T.  Burns  P.E.  Andrew  B.  Lockman  J.  Russell  Snow  黄学刚译 《岩土钻凿工程》2011,(2):77-81
大草原水利项目(PWP)将增加奥罗拉市百分之二十的城市供水,每年提供高达一万英亩一英尺(约33亿加仑)的水。PWP项目的一个关键因素是输送系统,该系统由直径为60英寸、约33英里长的地下原水传输管道,15个非开挖隧道(包括南普拉特河)和三个抽水站组成,该抽水站将亚当斯县的南普拉特河水垂直提升900英尺输送到奥罗拉市的新彼得宾尼净水设施。非开挖方法被用来构建水路、湿地、高速公路、干道和铁路下面的管线。南方普拉特河非开挖隧道是该项目最重要和具有挑战性的工程之一。南普拉特河隧道的地层条件的特点是由从细粒到粗粒砂组成的冲积层,与河漫滩沉积物凝聚的砾石,局部地方含有卵石和石块,基岩上覆盖着粘土岩。冲积层有25—30英尺厚,一般具有高渗透性和高储水能力,而粘土岩渗透性低。该隧道长约260英尺,在粘土岩中隧道的最大深度为48英尺,并配有一个直径78英寸的钢护筒、一条直径60英寸的钢管道以及支持系统监控和数据采集(SCADA)的通信光纤电缆或管道。本文介绍了与南普拉特河隧道相关的风险管理。此外,本文还探讨了,在不影响美国联邦监管的水域及美国工程兵管辖范围内的湿地的情况下,与工程建设有关的独特设计和施工挑战。  相似文献   
707.
The present study aimed at characterizing the heavy metal resistance and assessing the resistance pattern to multiple heavy metals (300 mmol L?1) by Palk Bay sediment bacteria. From 46 isolates, 24 isolates showed resistance to more than eight heavy metals. Among the 24 isolates S8-06 (Bacillus arsenicus), S8-10 (Bacillus pumilus), S8-14 (B. arsenicus), S6-01 (Bacillus indicus), S6-04 (Bacillus clausii), SS-06 (Planococcus maritimus) and SS-08 (Staphylococcus pasteuri) exhibited high resistance against arsenic, mercury, cobalt, cadmium, lead and selenium. Plasmid curing confirmed that the heavy metal resistance in S8-10 is chromosomal borne. Upon treatment with the heavy metals, the strain S8-10 showed many morphological and physiological changes as shown by SEM, FTIR and AAS analysis. S8-10 removed 47% of cadmium and 96% of lead from the growth medium. The study suggests that sediment bacteria can be biological indicators of heavy metal contamination.  相似文献   
708.
Coral reefs in the Negril Marine Park (NMP), Jamaica, have been increasingly impacted by nutrient pollution and macroalgal blooms following decades of intensive development as a major tourist destination. A baseline survey of DIN and SRP concentrations, C:N:P and stable nitrogen isotope ratios (δ15N) of abundant reef macroalgae on shallow and deep reefs of the NMP in 1998 showed strong P-limitation and evidence of increasing sewage pollution. In 1999, a sewage collection and treatment project began divertin...  相似文献   
709.
Growth-related characters, condition factor, and genetic differentiation were investigated for a single cohort of young-of-the-year (YOY) sole within and among nurseries with differing levels of heavy metals (Cd, Cu and Zn) contamination in the two Charentais Straits, Bay of Biscay, France. Analyses were performed when individuals recruited (May), then after a full summer spent in each nursery (October). Levels of phenotypic and genetic diversity were compared, together with genetic differentiation at a candidate metallothionein (MT) locus and three putatively neutral microsatellite loci. No phenotypic or genetic differentiation was detected among nurseries in May, but significant variation at each phenotypic trait and at the multilocus level in October (P < 0.001). Single locus analysis demonstrated that only the MT locus was significantly differentiated among nurseries, whether corrected for null alleles or not (θ=0.0401 and θ(corr.FreeNA)=0.0326, respectively; P < 0.001). Results indicate that phenotypic differences among YOY sole nurseries present a molecular correlate acting at identical spatio-temporal scales among nurseries, potentially reflecting differential selective pressure among nurseries in response to contamination.  相似文献   
710.
Geohazards appear to be increasing in frequency globally. It is of necessity to actively manage these natural hazards to minimize loss of life and property. From an early warning perspective, this paper stresses the potential fatal flood hazard represented by the huge volume of water in Tianchi Lake, the unique geography of Changbai Mountain, and the limited flood control ability in the upstream of the Songhua River. Northeast Asian countries should keep a watchful eye on the Changbai volcano cooperatively,...  相似文献   
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