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801.
碳酸盐岩中不同赋存状态有机质地球化学特征对比及对成烃的贡献 总被引:4,自引:1,他引:3
碳酸盐沉积物特殊的成岩机理和过程决定了有机质的复杂赋存状态,在碳酸盐岩中,除分散有机质外,还存在包裹体有机质。在包裹体有机质的提取过程中,当用6%(质量分数)的盐酸酸解碳酸盐矿物时,又将包裹体中的一部分有机质分离出(部分呈悬浮状态),本文定义为酸溶有机质I。对这三部分可溶有机质的含量、红外光谱、GC、GC-MS等分析表明它们的特征是不同的,并且分散有机质和包裹有机质在不同演化阶段对成烃的贡献不同。这为评价碳酸盐岩生烃潜力以及研究碳酸盐岩生烃机制和过程奠定了基础。 相似文献
802.
803.
铀矿堆浸,溶浸液在铀矿堆中的渗流对浸出效果有非常重要的影响,研究堆浸铀矿堆的渗透特性,对改善铀矿堆浸效果具有重要的意义。采用取自我国南方某铀矿山的堆浸铀矿石,配制10组不同粒径分维数的试样,利用自制的饱和渗流试验装置,对其液体饱和渗流的规律进行试验研究,获得相应的渗透率和流态指数。利用试验结果,分析粒径分维数对渗透率的影响。采用支持向量机(SVM)模型,以粒径分维数和孔隙率作为输入量,建立渗透率和流态指数预测模型。结果表明,(1)在文中试验条件下,堆浸铀矿堆的液体饱和渗流遵循非Darcy指数定律,流态指数在1.1~1.5之间,且渗透率随着粒径分维数的增加而逐渐减小;(2)渗透率的SVM预测模型和流态指数的SVM 预测模型给出预测值的相对误差分别低于8%和7%,可以满足工程应用的要求。 相似文献
804.
机载微波辐射计测云中液态水含量(Ⅱ):反演方法 总被引:6,自引:0,他引:6
介绍了机载对空微波辐射计探测云中路径积分液态水含量(L)的辐射传输原理和反演方法;根据吉林省长春市的历史探空资料和典型的层状云液水垂直分布模式,得到该地区4~7月各月随高度而变化的反演公式系数的表达式,并给出了反演误差的数值模拟检验结果:在地面反演值对“真值”的统计相对偏差是15%~25%,在6km高度处为5%~10%,表明该方法已具有实用可接受的精度。此外,为减少由于回归样本中云液水廓线的“失真”给反演造成的误差,本文在对探空廓线作诊断建立云液水廓线时,引入了实际目测最低云底高的信息。数值模拟比较表明,该措施行之有效,使对流层中下层几乎所有高度上L反演值的精度提高了5%~20%,观测高度越低,精度提高的越多。 相似文献
805.
806.
高液限土填料改良的最佳掺砂砾石比试验研究 总被引:3,自引:0,他引:3
对永宁高速公路高液限土填料进行掺砂砾石改良试验,首先分析确定了试验中的重要影响因素并制定了相应的对策,以保证试验结果的可靠性;通过大量的试验得到了不同高液限土的最佳掺砂砾石比,为合理有效地利用高液限土积累了经验,并为类似工程的设计和施工提供了参考。 相似文献
807.
808.
Konstantinos Mykoniou Christoph Butenweg Britta Holtschoppen Sven Klinkel 《地震工程与结构动力学》2016,45(11):1779-1796
A refined substructure technique in the frequency domain is developed, which permits consideration of the interaction effects among adjacent containers through the supporting deformable soil medium. The tank‐liquid systems are represented by means of mechanical models, whereas discrete springs and dashpots stand for the soil beneath the foundations. The proposed model is employed to assess the responses of adjacent circular, cylindrical tanks for harmonic and seismic excitations over wide range of tank proportions and soil conditions. The influence of the number, spatial arrangement of the containers and their distance on the overall system's behavior is addressed. The results indicate that the cross‐interaction effects can substantially alter the impulsive components of response of each individual element in a tank farm. The degree of this impact is primarily controlled by the tank proportions and the proximity of the predominant natural frequencies of the shell‐liquid‐soil systems and the input seismic motion. The group effects should be not a priori disregarded, unless the tanks are founded on shallow soil deposit overlying very stiff material or bedrock. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
809.
R. J. de Meijer F. D. Smit F. D. Brooks R. W. Fearick H. J. Wörtche F. Mantovani 《Earth, Moon, and Planets》2006,99(1-4):193-206
The programme Earth AntineutRino TomograpHy (EARTH) proposes to build ten underground facilities each hosting a telescope.
Each telescope consists of many detector modules, to map the radiogenic heat sources deep in the interior of the Earth by
utilising direction sensitive geoneutrino detection. Recent hypotheses target the core-mantle boundary (CMB) as a major source
of natural radionuclides and therefore of radiogenic heat. A typical scale of the processes that take place at the CMB is
about 200 km. To observe these processes from the surface requires an angular resolution of about 3°. EARTH aims at creating
a high-resolution 3D-map of the radiogenic heat sources in the Earth’s interior. It will thereby contribute to a better understanding
of a number of geophysical phenomena observed at the Earth’s surface. This condition requires a completely different approach
from the monolithic detector systems as e.g. KamLAND.
This paper presents, for such telescopes, the boundary conditions set by physics, the estimated count rates, and the first
initial results from Monte-Carlo simulations and laboratory experiments. The Monte-Carlo simulations indicate that the large
volume telescope should consist of detector modules each comprising a very large number of detector units, with a cross section
of roughly a few square centimetres. The signature of an antineutrino event will be a double pulse event. One pulse arises
from the slowing down of the emitted positron, the other from the neutron capture. In laboratory experiments small sized,
10B-loaded liquid scintillation detectors were investigated as candidates for direction sensitive, low-energy antineutrino detection. 相似文献
810.
The Gronnedal-Ika Carbonatite-Syenite Complex, South Greenland: Carbonatite Formation by Liquid Immiscibility 总被引:1,自引:0,他引:1
HALAMA RALF; VENNEMANN TORSTEN; SIEBEL WOLFGANG; MARKL GREGOR 《Journal of Petrology》2005,46(1):191-217
The Grønnedal-Ika complex is dominated by layered nephelinesyenites which were intruded by a xenolithic syenite and a centralplug of calcite to calcitesiderite carbonatite. Aegirineaugite,alkali feldspar and nepheline are the major mineral phases inthe syenites, along with rare calcite. Temperatures of 680910°Cand silica activities of 0·280·43 weredetermined for the crystallization of the syenites on the basisof mineral equilibria. Oxygen fugacities, estimated using titanomagnetitecompositions, were between 2 and 5 log units above the fayalitemagnetitequartzbuffer during the magmatic stage. Chondrite-normalized REE patternsof magmatic calcite in both carbonatites and syenites are characterizedby REE enrichment (LaCNYbCN = 1070). Calcite fromthe carbonatites has higher Ba (5490 ppm) and lower HREE concentrationsthan calcite from the syenites (54106 ppm Ba). This isconsistent with the behavior of these elements during separationof immiscible silicatecarbonate liquid pairs. Nd(T =1·30 Ga) values of clinopyroxenes from the syenites varybetween +1·8 and +2·8, and Nd(T) values of whole-rockcarbonatites range from +2·4 to +2·8. Calcitefrom the carbonatites has 18O values of 7·8 to 8·6and 13C values of 3·9 to 4·6. 18Ovalues of clinopyroxene separates from the nepheline syenitesrange between 4·2 and 4·9. The average oxygenisotopic composition of the nepheline syenitic melt was calculatedbased on known rockwater and mineralwater isotopefractionation to be 5·7 ± 0·4. Nd and COisotope compositions are typical for mantle-derived rocks anddo not indicate significant crustal assimilation for eithersyenite or carbonatite magmas. The difference in 18O betweencalculated syenitic melts and carbonatites, and the overlapin Nd values between carbonatites and syenites, are consistentwith derivation of the carbonatites from the syenites via liquidimmiscibility. KEY WORDS: alkaline magmatism; carbonatite; Gardar Province; liquid immiscibility; nepheline syenite 相似文献