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61.
运用电感耦合等离子质谱(ICP-MS)、X射线荧光光谱(XRF)、离子选择电极(ISE)、显微镜光度计和煤化学等方法,对山东济宁矿区的高硫煤(太原组16号煤层)与低硫煤(山西组3上煤层)剖面的煤岩、煤质和煤地球化学特征进行研究。高硫煤中微量元素在垂向上呈现显著的变化规律:(1)Sr含量从煤层底板到顶板呈增高趋势,而Ba含量则相反;因而Sr/Ba比值从下向上呈逐渐变大趋势(0.04~47.7);(2)Th/U比值从下向上也呈逐渐变大趋势(0.2~37.1);(3)As含量在煤层顶板石灰岩(26.1μg/g)、透镜状黄铁矿夹层(14.7~19.3μg/g)中较高;(4)V、Cr、Co、Ni、Cu、Pb、Zn等元素在煤层底部和顶部分层中含量较高,而在煤层中部分层中含量较低;(5)Nb、Ta、Zr、Hf、Ga等元素从煤层的底部到顶部呈逐渐降低趋势;(6)煤中稀土元素总量(REE),除透镜状黄铁矿夹层(第2、4、11分层)外,其它分层(第1、3、5、6、7、8、9、10分层)显示从上往下逐渐增高之规律性。低硫煤中微量元素的分布和垂向变化与高硫煤明显不同:As含量在14个煤分层中都较低(1.03~3.37μg/g),Sr/Ba比值从下向上变化不大(0.4~2.2),各个煤分层中稀土元素总量(REE)呈现随灰份含量增高而增高的变化趋势,低硫煤与高硫煤的稀土元素分布模式差别很大。上述研究结果表明济宁矿区高硫煤与低硫煤在地球化学特征上的差别,反映了上石炭统太原组与下二叠统山西组沉积环境和聚煤条件的差别,具有指相意义;太原组16号煤层中富集的硫及有害微量元素,对环境具有潜在危害。 相似文献
62.
利用雷电定位系统进行电网雷击故障快速查询 总被引:1,自引:0,他引:1
At present, lightning is one of the 10 natural disasters, and it is also the top environmental factor of power interruption. It often causes huge losses to the electric system. The Wuhan High Voltage Institute of the State Grid Corporation of China and Huazhong University of Science and Technology have been researching and developing lightning location systems (LLSs) since the late 1980s. In the mid-1990s, a lightning detection network was created in 29 provinces and cities in China. It is primarily applied to rapidly find lightning accidents, which greatly reduces power interruption. Also, it ensures high efficiency and safe operation of the electricity system. Remarkable benefit is achieved. China's LLS went through an "orientation positioning - time difference positioning - integrated positioning" development process. The positioning precision, detection efficiency, degree of automation, practicability and applied range are improved. Also, a lightning information system plan of the national network has been implemented, which services the whole society. 相似文献
63.
Remarkable progress has been made in electromagnetic (EM) techniques as applied to the petroleum industry in instruments,
data acquisition, and processing and interpretation in China. Included here is equipment, such as high-power Controlled Source
EM (CSEM) acquisition systems, acquisition methods, such as the three dimensional small-bin Continuous Electromagnetic Array
acquisition method, Time and Frequency Domain Controlled Source Electromagnetic, Borehole-to-surface Electromagnetic technique
and marine magnetotelluric method. Data processing methods, such as fast three dimensional inversion using nonlinear conjugate
gradients, and data interpretation methods, like Induced Polarization and Resistivity anomalies for hydrocarbon detection,
are also included. These new techniques have been applied in petroleum survey and many cases are in complicated areas. They
have successfully served the investigation of deep igneous rock reservoirs, and prediction of potential hydrocarbon targets.
The cases indicate that electromagnetic techniques can help seismic survey to effectively detect hydrocarbon reservoir and
remarkably improve drilling successes. 相似文献
64.
1768记录器走纸电机驱动电路的过去和现状768记录器以其先进的技术性能和使用功能,已成为国内几乎所有模拟遥测地震台网一致选用的记录设备。但由于它诞生于70年代,以今天的水准来看,它所采用的一些电路技术已显得陈旧落后,走纸电机驱动电路就是其中之一。7... 相似文献
65.
The effects of four microalgae,Chlorella vulgaris,Platymonas helgolandicavar,Isochrysis galbana,and Nitzschia closterium on the grazing and filtering rates of the marine rotifer,Brachionus plicatilis,were evaluated under laboratory conditions.The grazing rates in separate cultures of the four microalga were as follows:C.vulgaris > P.helgolandicavar > I.galbana > N.closterium.However,the filtering rates occurred in the following order:P.helgolandicavar > N.closterium > C.vulgaris > I.galbana.A mixed diets ex... 相似文献
66.
A. Foubert D. Van Rooij D. Blamart J.-P. Henriet 《International Journal of Earth Sciences》2007,96(1):141-158
Three provinces, characterized by the presence of carbonate mounds interpreted as cold-water coral banks have been reported
in Porcupine Seabight, SW of Ireland and were recently subjected to many detailed studies. This contribution discusses the
use of X-ray imagery and physical properties in deciphering palaeoceanographic, sedimentological and biological processes.
Physical property core logging and X-ray imagery are used to identify and describe sedimentation regimes and so their respective
palaeoceanographic and palaeoclimatological settings in two mound provinces, respectively the Belgica mound province and the
Magellan mound province. Both provinces show at present time clear differences in the hydrodynamic environment. This study
confirms that also during the past the oceanographic and sedimentological environment of both provinces differ clearly. Impacts
of glacial–interglacial variations and locally derived ice rafting events (IRE), comparable with the North Atlantic Heinrich
events (HE) have been recognized in both provinces. Moreover, the combination of X-ray imagery, magnetic susceptibility, gamma
density and P-wave velocity makes it possible to estimate the coral content and coral distribution in unopened cores localized
on top of carbonate mounds. A comparison between on-mound and off-mound cores in both provinces allowed revealing some mechanisms
of mound evolution and coral growth versus time. 相似文献
67.
Celia Martín-Puertas Blas L. Valero-Garcés M. Pilar Mata Ana Moreno Santiago Giralt Francisca Martínez-Ruiz Francisco Jiménez-Espejo 《Journal of Paleolimnology》2011,46(3):405-421
High-resolution geochemical analysis of a 6-m-long sediment core from Zoñar Lake, southern Spain, provides a detailed characterization of major changes in lake and watershed processes during the last 4,000 years. Geochemical variables were used as paleolimnological indicators and complement Zoñar Lakes’s paleoenvironmental reconstruction based on sedimentological and biological proxies, which define periods of increasing allochthonous input to the lake and periods of dominant autochthonous sedimentation. Chemical ratios identify periods of endogenic carbonate formation (higher Ca/Al, Sr/Al and Ba/Al ratios), evaporite precipitation (higher S/Al, Sr/Al ratios), and anoxic conditions (higher Mo/Al, U/Th ratios and Eu anomaly). Higher productivity is marked by elevated organic carbon content and carbonate precipitation (Mg/Ca). Hydrological reconstruction for Zoñar Lake was based on sedimentological, mineralogical and biological proxies, and shows that lower lake levels are characterized by Sr-rich sediments (a brackish lake with aragonite) and S-rich sediments (a saline lake with gypsum), while higher lake levels are characterized by sediments enriched in elements associated with alumino-silicates (Al, K, Ti, Fe, trace and rare earth elements), reflecting fresher conditions. Geochemical indicators also mark periods of higher detrital input to the lake related to human activity in the watershed: (1) during the Iberian Roman Humid Period (650 BC–AD 300), around the onset of the Little Ice Age (AD 1400), during the relatively drier Post-Roman and Middle Ages (AD 800–1400), and over the last 50 years, due to mechanized farming practices. Heavy metal enrichment in the sediments (Cu and Ni) suggests intensification of human activities during the Iberian Roman Period, and the use of fertilizers during the last 50 years. 相似文献
68.
At high latitudes and in mountainous areas, evaluation and validation of water and energy flux simu-lations are greatly affected by systematic precipitation errors. These errors mainly come from topographic effects and undercatch of precipitation gauges. In this study, the Land Dynamics (LAD) land surface model is used to investigate impacts of systematic precipitation bias from topography and wind-blowing on water and energy flux simulation in Northwest America. The results show that topographic and wind adjustment reduced bias of streamflow simulations when compared with observed streamflow at 14 basins. These systematic biases resulted in a -50%-100% bias for runoff simulations, a -20%-20% bias for evapotranspiration, and a -40%-40% bias for sensible heat flux, subject to different locations and adjustments, when compared with the control run. Uncertain gauge adjustment leads to a 25% uncertainty for precipitation, a 20% 100% uncertainty for runoff simulation, a less-than-10% uncertainty for evapotranspiration, and a less-than-20% uncertainty for sensible heat flux. 相似文献
69.
70.
Jerzy Dec 《Acta Geophysica》2010,58(1):5-14
This paper shows the results of seismic research on some problems of sulphur in-situ mining. The difficulties during exploitation
were mainly connected with the lack of detailed information on the structure and tectonics of deposit and overburden strata.
This kind of information could be obtained using the High Resolution Seismic method.
The use of seismic method allows to determine the range of subsidence provoked by well mining of sulphur. It is very important
to undertake the measurements before exploitation, because the comparison of seismic sections before and during exploitation
creates a possibility of determining the process of changes in the structure of the deposit and overburden strata. 相似文献