排序方式: 共有41条查询结果,搜索用时 15 毫秒
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氟碳钙铈矿结构中晶体缺陷的高分辨电镜研究 总被引:1,自引:1,他引:1
用高分辨电子显微术(HREM)研究了氟碳钙铈矿(BS)晶体结构中的无序堆垛和体衍交生现象,结果表明该矿物的衍生多晶体是由钙-铈氟碳酸盐矿物中不同组分的氟碳铈矿(B)和直氟碳钙铈矿(S)结构单元层沿c方向无序堆垛而成。高分辨结构象揭示出氟碳钙铈矿衍生多晶体的微结构特征。讨论了氟碳钙铈矿结构中的堆垛层错等晶体缺陷现象。 相似文献
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钙-铈氟碳酸盐矿物系列中新规则混层矿物的晶格象研究 总被引:5,自引:2,他引:5
本文用电子衍射和晶格象技术研究钙-铈氟碳酸盐矿物微结构特征。除确定有氟碳铈矿(B),氟碳钙铈矿(BS)、伦琴矿(BS_2)和B_3S_2规则混层矿物外,还首次发现了9种B_mS_n(m≥++n)型新的规则混层矿物。这些新规则混层矿物,往往以共格的形式共存于一个自然晶粒之中。大量的SAED和晶格象揭示了这类稀土矿物各成员之间的相互结构关系。研究表明:钙-铈氟碳酸盐矿物系列中矿物衍生体的微结构特征及其变化是相当复杂的,它们是由不同组分的氟碳铈矿(B)和直氟碳钙铈矿(S)的结构单元层在c轴方向通过不同比例堆垛方式,形成一系列新规则混层矿物及多型。 相似文献
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选用气流磨超音速气流作为机械力,对硅灰石、硬脂酸进行超细粉碎-表面改性。应用透射电子显微镜分析、观察硅石灰/硬脂酸复合粉体界面微观形貌及成分(Ca、Si、C)的变化规律。TEM能谱分析结果表明:从硅灰石到硬脂酸,Ca、Si含量逐渐降低,C含量则逐渐升高。 相似文献
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Wan Rui Pan Zhaolu Shu Jinfu 《地球科学》1986,(6)
本文对攀枝花辉长岩体中共存的单斜、斜方辉石进行了系统的矿物学及晶体化学研究。首次查明该岩体中斜方辉石的成分,光性及结构特征。研究表明:单斜种属为次透辉石,其化学式为Ca_(0.831)Na_(0.027)K_(0.002)Mg_(0.811)Fe_(0.213)~(2+)Fe_(0.054)~(3+)AlⅥ_(0.030)Ti_(0.013)Mn_(0.008)AlⅣ_(0.082)Si_(1.918)O_6,晶胞参数为α=9.7443—9.7617,b=8.9174—8.9431,c=5.2353—5.2653,β=105°56'~106°8',空间群C2/c,Z=4;斜方辉石为紫苏辉石,化学式为Ca_(0.044)Na_(0.012)K_(0.005)Mg_(1.335)Fe_(0.584)~(2+)Ti_(0.007)Mn_(0.014)Al_(0.029)Si_(1.969)O_6,晶胞参数α=18.2720,b=8.8734,c=5.2078,空间群Pbca,Z=8,该岩体辉石的成分与布什维尔德和斯卡尔嘎得两侵入体中辉石的成分趋向一致。 相似文献
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通用土壤流失方程最新研究改进分析 总被引:4,自引:0,他引:4
通用土壤流失方程(USLE)是水动力土壤侵蚀研究领域应用广泛的经验模型。其结构简单,所需输入数据量少,计算结果可满足一定精度下,土壤侵蚀预测的要求。模型的改进使其应用范围扩大,适用性增强,计算精度提高。通用土壤流失方程的发展趋势:其一,传统方法,不改变模型的结构,通过引进合理的新参数或优化参数的取值来提高模型的预测能力;其二,非传统方法,通过模糊逻辑或人工神经网络方法来改变模型的结构,使土壤侵蚀影响因子的确定更加灵活合理,土壤流失量的计算结果更加精确可信。 相似文献
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Geochemistry and origin of sour gas accumulations in the northeastern Sichuan Basin, SW China 总被引:2,自引:0,他引:2
Jian Li Zengye Xie Jinxing Dai Shuichang Zhang Guangyou Zhu Zhaolu Liu 《Organic Geochemistry》2005,36(12):1703-1716
Significant natural gas reserves have recently been discovered in the Lower Triassic oolitic reservoirs from northeastern Sichuan Basin, SW China. In the wake of the December 2003 sour gas well blow-out, this study presents an overview on the petroleum geology and geochemistry of the sour gas accumulations in the study area. Two types of natural gas accumulations were identified in the Lower Triassic oolitic reservoirs, both containing highly mature thermogenic gases, with their hydrocarbon source rocks in Upper Permian strata. Natural gases from the area south of the ancient Kaijiang-Liangping Seaway are generally sweet gases formed as the result of thermal maturation, whereas those discovered from north of the Seaway are products of both thermal maturation and thermochemical sulfate reduction of early accumulated oils in the Feixianguan Formation reservoirs. The proposed origins of the gases are supported by their chemical and stable carbon isotope compositions, as well as the presence or absence of pyrobitumens in the reservoir. The distribution of gas accumulations is controlled predominantly by the combination of lithologic and structural factors. The regional variation in the concentrations of H2S in the gases appears related to the presence and thickness of anhydrite-bearing evaporitic rocks interbedded or intercalated with the oolitic reservoirs. 相似文献
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Xu Yidan Li Jianping Sun Cheng Lin Xiaopei Liu Hailong Wang Lanning Liang Yishuang Wang Qiuyun Zhang Yazhou Hou Zhaolu Wang Fuchang 《Climate Dynamics》2020,54(3):1295-1313
Climate Dynamics - The global mean surface air temperature (GMST) shows multidecadal variability over the period of 1910–2013, with an increasing trend. This study quantifies the contribution... 相似文献