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901.
902.
粉煤灰是电厂煤粉高温燃烧后的固体废弃物,也是用于提取氧化铝和制备陶瓷、微晶玻璃、耐火材料等高附加值产品的潜在资源。粉煤灰中的杂质铁对制备上述制品的工艺选择和制品质量、性能均有重大影响。本文对内蒙古准格尔电厂高铝粉煤灰(CFB灰)进行了脱碳除铁的实验研究。实验表明,粉煤灰经900℃煅烧2 h,基本上可除去碳;除铁的优化工艺条件为:盐酸浓度20%,液固比5∶1,温度为80℃,搅拌时间为60 min,除铁率达80%以上。 相似文献
903.
渤海湾西侧泥质海岸带全新世岸线的变化与海洋的影响(英文) 总被引:2,自引:2,他引:0
以渤海湾泥质海岸带为例,从形态和地层证据2个方面总结了全新世岸线变化与海洋作用对该地区海岸带发育的影响。中全新世以来千年级别的岸线变迁至少以6次停顿(形成贝壳堤和泥质岭地)和岸进的交替为特征。过去130年间10年级别的岸线变化分为4个阶段,显示了"小冰期"结束后随气温上升而发生的岸线自然蚀退是如何逐渐被人类活动(特别是2000年以来的围海造陆)所取代的。全新世海相沉积中发现的9个峰值期和晚全新世的7次风暴驱动事件,表明了研究区泥质海岸带增强的海洋影响。这些结果提供了一条经由地质背景认识现代泥质海岸带过程的途径。 相似文献
904.
Hong Zhang Hung-Lung Huang Agnes Lim Robert Holz Steve Dutcher Fred Nagle Liam Gumley Jinnian Wang Runhe Shi Wei Gao 《Frontiers of Earth Science》2010,4(3):363-373
The Atmospheric Infrared Sounder (AIRS) and MODerate-Resolution Imaging Spectroradiometer (MODIS) on board NASA Earth Observing
System (EOS) Aqua spacecraft measure the upwelling infrared radiance used for numerous remote-sensing- and climate-related
applications. AIRS provides high spectral resolution infrared radiances, while MODIS provides collocated high spatial resolution
radiances at 16 broad infrared bands. An optimal algorithm for cloud-clearing has been developed for AIRS cloudy soundings
at the University of Wisconsin-Madison, where the spatially and spectrally collocated AIRS and MODIS data has been used to
analyze the characteristic of this algorithm. An analysis and characterization of the global AIRS cloud-cleared radiances
using the bias and the standard deviation between the cloud-cleared and the nearby clear measurements are studied. Scene inhomogeneity
for both land- and water-surface types has been estimated to account for the assessed error. Both monthly and seasonal changes
of global AIRS/MODIS cloud-clearing performance also have been analyzed. 相似文献
905.
综合物探技术在煤系上覆薄硬岩矿区的应用初探——以山西潞安集团司马矿区为例 总被引:1,自引:0,他引:1
山西潞安集团司马矿区东高西低,西部延至长治盆地,矿区水系发育。主采3#煤层埋藏较浅,层位稳定。新生界不整合于下伏基岩之上,厚度变化较大,属典型的薄硬岩煤矿区。为准确提供矿区煤炭开采上限的地质依据,采用了综合勘探技术,其中利用三维地震勘探技术追踪新生界底面反射波及第四系"天窗"位置,利用直流电法与瞬变电磁法提供电性分层,并对其解释结果进行相互印证。勘探实例表明,三维地震勘探、电法勘探与钻探的综合运用不仅可解决薄硬岩煤矿区新生界厚度、含水层富水性及第四系缺失等问题,还可提供新生界含水层与基岩含水层之间的水力联系、制约因素等资料。 相似文献
906.
907.
In this study, the electrical resistivity of soil having different chemical weathering index (CWI) was measured, and the correlation
between CWI and the electrical resistivity was estimated. The electrical resistivity of soil varies with CWI of soil. The
difference in the electrical resistivities of soils having different weathering degrees is clear at lower water contents.
At the volumetric water contents estimated in this study, CWI could be described by a linear equation of electrical resistivity
with the constants related to the volumetric water content. The findings in this study suggest that the electrical resistivity
could be used as an effective alternative for estimating the weathering degree of soil. 相似文献
908.
Effects of natural and calcined oyster shells on Cd and Pb immobilization in contaminated soils 总被引:5,自引:0,他引:5
Yong Sik Ok Sang-Eun Oh Mahtab Ahmad Seunghun Hyun Kwon-Rae Kim Deok Hyun Moon Sang Soo Lee Kyoung Jae Lim Weon-Tai Jeon Jae E. Yang 《Environmental Earth Sciences》2010,61(6):1301-1308
In Korea, soils adjacent to abandoned mines are commonly contaminated by heavy metals present in mine tailings. Further, the
disposal of oyster shell waste by oyster farm industries has been associated with serious environmental problems. In this
study, we attempted to remediate cadmium (Cd)- and lead (Pb)-contaminated soils typical of those commonly found adjacent to
abandoned mines using oyster shell waste as a soil stabilizer. Natural oyster shell powder (NOSP) and calcined oyster shell
powder (COSP) were applied as soil amendments to immobilize Cd and Pb. The primary components of NOSP and COSP are calcium
carbonate (CaCO3) and calcium oxide (CaO), respectively. X-ray diffraction, X-ray fluorescence and scanning electron microscope analyses conducted
in this study revealed that the calcination of NOSP at 770°C converted the less reactive CaCO3 to the more reactive CaO. The calcination process also decreased the sodium content in COSP, indicating that it was advantageous
to use COSP as a liming material in agricultural soil. After 30 days of incubation, we found that the 0.1 N HCl-extractable
Cd and Pb contents in soil decreased significantly as a result of an increase in the soil pH and the formation of metal hydroxides.
COSP was more effective in immobilizing Cd and Pb in the contaminated soil than NOSP. Overall, the results of this study suggest
that oyster shell waste can be recycled into an effective soil ameliorant. 相似文献
909.
Delineation of landslide hazard areas on Penang Island, Malaysia, by using frequency ratio, logistic regression, and artificial neural network models 总被引:23,自引:5,他引:18
This paper summarizes findings of landslide hazard analysis on Penang Island, Malaysia, using frequency ratio, logistic regression, and artificial neural network models with the aid of GIS tools and remote sensing data. Landslide locations were identified and an inventory map was constructed by trained geomorphologists using photo-interpretation from archived aerial photographs supported by field surveys. A SPOT 5 satellite pan sharpened image acquired in January 2005 was used for land-cover classification supported by a topographic map. The above digitally processed images were subsequently combined in a GIS with ancillary data, for example topographical (slope, aspect, curvature, drainage), geological (litho types and lineaments), soil types, and normalized difference vegetation index (NDVI) data, and used to construct a spatial database using GIS and image processing. Three landslide hazard maps were constructed on the basis of landslide inventories and thematic layers, using frequency ratio, logistic regression, and artificial neural network models. Further, each thematic layer’s weight was determined by the back-propagation training method and landslide hazard indices were calculated using the trained back-propagation weights. The results of the analysis were verified and compared using the landslide location data and the accuracy observed was 86.41, 89.59, and 83.55% for frequency ratio, logistic regression, and artificial neural network models, respectively. On the basis of the higher percentages of landslide bodies predicted in very highly hazardous and highly hazardous zones, the results obtained by use of the logistic regression model were slightly more accurate than those from the other models used for landslide hazard analysis. The results from the neural network model suggest the effect of topographic slope is the highest and most important factor with weightage value (1.0), which is more than twice that of the other factors, followed by the NDVI (0.52), and then precipitation (0.42). Further, the results revealed that distance from lineament has the lowest weightage, with a value of 0. This shows that in the study area, fault lines and structural features do not contribute much to landslide triggering. 相似文献
910.
Sammy Griffin Arya Udry Luke Daly Lucy Victoria Forman Martin R. Lee Benjamin E. Cohen 《Meteoritics & planetary science》2023,58(1):63-84
To better understand volcanism on planetary bodies other than the Earth, the quantification of physical processes is needed. Here, the petrogenesis of the achondrite Martian Yamato (Y) nakhlites (Y 000593, Y 000749, and Y 000802) is reinvestigated via quantitative analysis of augite (high-Ca clinopyroxene) phenocrysts: crystal size distribution (CSD), spatial distribution patterns (SDP), and electron backscatter diffraction (EBSD). Results from CSD and EBSD quantitative data sets show augite to have continuous uninterrupted growth resulting in calculated minimum magma chamber residence times of either 88–117 ± 6 yr or 9–12 yr. All samples exhibit low-intensity S-LS type crystallographic preferred orientation. Directional strain is observed across all samples with intracrystalline misorientation patterns indicative of (100)[001]:(001)[100] (Y 000593 and Y 000802) and {110}<001>or {110}1/2<110> (Y 000749) slip systems. SDP results indicate phenocryst-bearing crystal-clustered rock signatures. Combined findings from this work show that the Yamato nakhlites formed on Mars as individual low-viscosity lava flows or sills. This study shows that through combining these different quantitative techniques over multiple samples, one can more effectively compare and interpret resulting data to gain a more robust, geologically contextualized petrogenetic understanding of the rock suite being studied. The techniques used in this study should be equally applicable to igneous achondrites from other parent bodies. 相似文献