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951.
ZhongPing Lee Mingshun Jiang Curtiss Davis Nima Pahlevan Yu-Hwan Ahn Ronghua Ma 《Ocean Science Journal》2012,47(3):323-329
Ocean-color imagers on conventional polar-orbiting satellites have a revisit time of ??2 days for most regions, which is further reduced if the area is frequently cloudy. The Geostationary Ocean Color Imager (GOCI), the first ocean-color imager on a geostationary satellite, provides measurements 8 times a day, thus significantly improving the frequency of measurements for studies of ocean environments. Here, we use results derived from GOCI measurements over Taihu Lake to demonstrate that the extra sampling can be used to improve the accuracy of statistically averaged longer-term (daily) measurements. Additionally, using numerical simulations, we demonstrate that the coupling of diurnal variations of both biomass and photosynthetic available radiation can improve the accuracy of daily primary production estimates. These results echo that higher sampling frequency can improve our estimates of longer-term dynamics of biogeochemical processes and highlights the value of ocean color measurements from geostationary satellites. 相似文献
952.
Mineral constituents in common chanterelles and soils collected from a high mountain and lowland sites in Poland 总被引:1,自引:1,他引:0
This paper reported the results of the determination of Ag, Al, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, Pb, Rb, Sr and Zn in Common Chanterelles (Cantharellus cibarius) Fr. and surface soil layer (0-10 cm) underneath the fruiting bodies. Mushrooms and soils were collected from a lowland site in the Hel Peninsula (Baltic Sea coast) and a high mountain site in the Tatra Mountains. The trace elements were determined using validated method and inductively coupled plasma - atomic emission spectroscopy (ICP-AES). Common Chanterelles that emerged at sites poor in mineral nutrients podzols of the Hel Peninsula forests efficiently bioconcentrated several essential trace elements (K, P, Co, Cu, Mn, Na, Zn), while the abundance of those elements in carpophores was around half less compared to specimens from Zakopane region and which emerged in soils much richer in minerals. Common Chanterelles collected at two spatially distant background areas in Poland were only weakly contaminated with metals such as Ag, Cd, Hg and Pb. The maximum tolerable Cd and Pb contents of certain cultivated mushrooms are regulated in the European Union by law and these hazardous metals in C. cibarius were far below tolerance limits set. 相似文献
953.
根据地质构造及地震台网分布特征,将青海地区分为柴达木盆地、青海东北部、青海东南部3个区域,运用青海地震台网记录的112条数字地震波形资料,利用Atkinson方法得到3个区域的非弹性衰减Q值随频率的关系,结果表明,柴达木盆地Q值最大,青海东南部Q值最小。采用Moya方法反演得到3个区域24个地震台的场地响应,其中15个台站的场地响应在频率域不平坦,9个台站稳定性相对较好,GOM(格尔木)作为国家基准地震台,具有良好的观测环境,场地响应曲线稳定。 相似文献
954.
F-X域经验模态分解去噪方法在处理非稳态地震数据时存在两个局限,一是单纯剔除第一个固有模态分量将导致有效信号缺失及去噪能力偏弱问题,二是分解复信号时对实部和虚部分别分解存在分解数目不一致的风险。本文对上述两个方面进行了改进,提出了一种新的F-X域投影法复数经验模态分解预测滤波方法,首先采用基于空间投影的复数经验模态分解将F-X域地震数据直接分解为不同的复固有模态分量,然后再对这些分量分别进行F-X域预测滤波。合成记录及实际资料测试表明,本文的新方法能更好地衰减随机噪声,更有效地保持地震信号。 相似文献
955.
956.
The source material, precursor and formation processes of chlorite rims, and impact of pore-lining chlorite on reservoir quality of the Shiqianfeng sandstones, Dongpu Depression, Bohai Bay Basin, China, are studied using an integrated approach, including core observation, point-count analysis of thin-sections, scanning electron microscopy, electron microprobe analysis and cathode luminescence. The petrographic analysis shows that chlorite rims consist of grain-coating chlorite, poorly crystalline pore-lining chlorite and euhedral-crystallised pore-lining chlorite. The chemical composition shows that pore-lining chlorite is mainly Fe-rich with an average of 0.785 for Fe/(Fe+Mg) ratio. Petrographic analysis shows a large amount of volcanic dust (3.0~16.0 vol%, average of 7.93 vol%) in Shiqianfeng sandstones, which determines the formation of poorly crystalline pore-lining chlorite. Transformation of volcanic dust to smectite rims started with shallow burial depth at an early diagenetic stage, followed by in situ alteration of the smectite rims to poorly crystalline chlorite rims. Euhedral-crystallised chlorite mainly develops in sandstones with high porosity, high permeability and open flow systems. Pore-lining chlorite can inhibit quartz overgrowth but cannot effectively prevent pore-filling of authigenic quartz, carbonate and kaolinite cements, and therefore cannot prevent porosity destruction. However, the occurrence of pore-lining chlorite is a barometer of good reservoir quality and intense hydrodynamic conditions. 相似文献
957.
Destructions resulted from natural hazards like earthquake, landslide, or flood in the urban roads and lifelines introduce their negative effects including the psychological damage to citizens as well as decreased urban functions that usually last for a long time. Thus, a quick and efficient recovery of infrastructures, lifelines, and service-providing facilities along with reducing reconstruction costs and time are essential. This paper proposed an approach that consists of four models for forming an algorithm in order to quantitating and integrating of the criteria that have decisive influence in the recovery of urban roadways after a natural disaster. Meanwhile, to aggregate and conclude the data that are collected by means of presented functions and formulations, we applied fuzzy VIKOR technique as a compromise ranking method. The model outputs a priority list showing the revival of which urban paths stands in higher priority for recovery operation after a natural disaster. Results show that not only the model is able to precisely quantize the selected criteria and provide an action plan for post-event recovery prioritization, but also it offers an appropriate order of transportation roads priority for recovery operations. Finally, the results from the recovery model application to a roadway system in Tehran area are provided. 相似文献
958.
Grilli Stéphan T. Shelby Mike Kimmoun Olivier Dupont Guillaume Nicolsky Dmitry Ma Gangfeng Kirby James T. Shi Fengyan 《Natural Hazards》2017,86(1):353-391
Natural Hazards - We perform numerical simulations to assess how coastal tsunami hazard from submarine mass failures (SMFs) is affected by slide kinematics and rheology. Two types of two-layer SMF... 相似文献
959.
Liu Yi nan Sun Fengxia Cui Yueju Pan Xiaodong Ma Mingzhi Zhang Xin Du Jianguo 《地球科学进展》2017,32(8):810-817
The hydrochemical types and origins of underground water in Songyuan and vicinity, Liaoning Province were discussed based on the hydrochemical composition, δD and δ18O. The water samples from eight wells were collected 4 times during 2014 to 2015. The main ion concentrations of water were analyzed with an Ion Chromatography. Isotopic compositions of hydrogen and oxygen were analyzed with the Liquid Water Isotope Analyzer. The mineralization (TDS) of the water ranged from 125.4 mg/L to 19 350.9 mg/L. Values of δD and δ18O ranged from -71.7‰ to -98.1‰ and from -9.0‰ to -12.5‰, respectively. The isotopic data indicated that the water originated from meteorological precipitation. The chemical compositions of Taolaizhao phreatic water were influenced by the human activity while the other water samples collected from artesian well were less affected by the human activity. Water in Changling, Dongdashi, Taohaotai, Qianan and Ningjiang were characterized by HCO3-Na with low TDS values. Such chemical types of water with fluctuations of Na+, SO 4 2 - and δ18O drift were resulted from dissolving silicate minerals and adding surfactant during oil exploitation. Fresh water in Fuyu well was Cl-Na type, which was influenced by acid injection during oil exploitation. Water in Qianguo well was characterized by Cl-Na type with TDS up to 19 350.9 mg/L, the obvious fluctuations of hydrogen and oxygen isotopes and increasing ion concentrations in the Qianguo well may be caused by the earthquakes that occurred in the sampling duration. The results will provide the background of hydrochemistry, and will be of benefit to monitoring earthquake and certificating seismic-chemical anomalies in the future. 相似文献
960.
由于北京的地理位置较为特殊,地质构造较为复杂,冲洪积扇和古河道等作用较为多样,第四纪地层剖面标准化工作进行的还不够详尽,发展较其他城市稍显滞后。本文通过前人对北京市平原区第四纪地层的划分,在已有基准孔网和三维结构的基础上,对常营地区第四纪地层进行了更为详尽的标准化分层(共分为39层),进而利用计算机建立了标准地层数据库,完成了三维准自动化地质体模型构建工作,实现了地面沉降模型与视电阻率属性模型的耦合显示,进行了基本分析,验证了研究区相同流域,距离1km2的区域通过标准化分层自动构建地质体模型。 相似文献