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1.
Monjurosuchus splendens是辽宁西部热河生物群中最早被正式命名的爬行类化石,该属种名称在最初以英文发表的论文中并没有明确其含义,导致它的中文称谓有“文珠龙”（属名）、“荣耀满洲鳄”、“楔齿满洲鳄”等几种说法。本文认为属名（Monjurosuchus）应尊重最初命名者论文中的日文摘要表述的含义,称之为“满洲鳄”,而种名（splendens）的拉丁文并不是“楔齿”之义,应按其本义译为“华丽”,因而Monjurosuchus splendens的正确中文译名应为“华丽满洲鳄”。华丽满洲鳄的分类位置、以及其与辽宁西部另一爬行类化石“东方喙龙Rhynchosaurus orientalis”的关系长期以来亦存在着不同看法,直到20世纪末和21世纪初Monjurosuchus splendens作为有效属种名称被再次确认且被正确归入离龙目（Choristodera）。本文回顾了该属种研究历史及其分类位置的认识变化情况,支持将其归入离龙目（Choristodera）满洲鳄科（Monjurosuchidae）、而且“东方喙龙Rhynchosaurus orientalis”为华丽满洲鳄Monjurosuchus splendens的晚出同物异名这一观点。 相似文献
2.
R. Rinaldi G. Artioli C. C. Wilson G. McIntyre 《Physics and Chemistry of Minerals》2000,27(9):623-629
Crystallographic determinations on natural olivine single crystals of mantle composition and origin, carried out by in situ neutron diffraction at high temperature, show that the octahedrally co-ordinated Fe2+ and Mg cations undergo two successive trends of cation ordering with increasing temperature. An initial slight preference of Fe2+ for site M1, up to a temperature of about 850?°C, is followed by a reverse-ordering reaction with a site preference exchange between the two cations. The cross-over between the two regimes of ordering, corresponding to a situation of complete disorder, occurs at about 900?°C. Above this temperature Fe2+ progressively and strongly segregates into site M2 up to 1300?°C, the practical limit of the experimental setup utilized in the experiments. Care was taken to ensure that no chemical changes occurred in the crystals (i.e. oxidation), as testified by Mössbauer spectroscopy determinations carried out before and after the heat treatment. The cation-ordering behaviour is reflected in temperature-dependent changes of geometrical and atomic displacement parameters occurring in the octahedral sites M1 and M2. A thermodynamical explanation of this behaviour is proposed in terms of a prevailing vibrational contribution to entropy. 相似文献
3.
变形体的变形模式确定的情况下,应用灵敏度准则进行监测网的设计;根据Ｔａｙｏｒ展式,导出了监测网顾及灵敏度准则的二类设计模型,并对其解算及模拟算例加以说明。 相似文献
4.
研究了复平面上 ,广义 Hermite-Fejer插值多项式的收敛性。得到了其在空间 lp(| z| =1 ) (0 相似文献
5.
The crystal structures, lattice dynamics and magnetic properties of synthetic Co-cordierite, Co2Al4Si5O18, and Mn-cordierite, Mn2Al4Si5O18 have been studied by neutron powder diffraction, infrared spectroscopy and magnetisation measurements. Due to different synthesis
conditions, the Co-cordierite used here crystallised in the hexagonal α-cordierite structure with a disordered Si/Al distribution
in the framework, while for the Mn-cordierite the orthorhombic β-structure has been determined. The experimentally determined
paramagnetic moments,
exp
(Mn) = 5.47(6)
B
and
exp
(Co) = 3.88(4)
B
, are in good agreement with theoretical predictions for octahedrally coordinated Mn2+ and Co2+, respectively. In both compounds there is no magnetic long-range order down to at least 1.5 K. However, the onset of an anti-ferromagnetic
short-range correlation of magnetic moments along [001] has been observed for Mn-cordierite by magnetisation and neutron diffraction
measurements. This short-range magnetic correlation becomes evident from diffuse scattering observed at 2 K. The diffuse scattering
has been interpreted in terms of a Blech-Averbach function.
Received: 30 June 1998 / Revised, accepted: 3 March 1999 相似文献
6.
自然数可以视为反映世界客观本质的一种重要秩序，即信息，它不因加法处理而失真［１］。强地震在一定的时空范围内重复出现的现象称为有序性。自１７１６年以来，新疆及其邻区７级以上强震在时间上具有良好的有序性，有些强震在空间上亦表现出一定的有序性。强地震时间间隔值以６０、３０、４１、１９和１１年占据主导分布，并且相互之间关系密切。根据强震活动的有序性结构可进行预测：该地区未来Ｍ≥７强震可能发生在２００４年和２０１５年前后。 相似文献
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8.
陕西韩城-旬邑地区中奥陶统马家沟组豹斑白云岩研究 总被引：1，自引：0，他引：1
鄂尔多斯盆地奥陶系马家沟组白云岩是重要的油气储集层.从野外露头观察,白云岩斑块多呈管状、不规则状,是生物扰动后留下的虫孔遗迹.从镜下观察,斑块主要沿虫孔分布,成分为半自形-自形细粉晶白云石或具雾心亮边,基质为泥晶白云石.对研究区全岩C,O同位素和白云石有序度进行分析,得出白云石δ13C平均值为-0.26‰,δ18O平均-5.06‰;白云石CaCO3摩尔百分含量平均为50.4%,有序度为0.81~1.结合白云岩形成于半局限云质洼地沉积环境,认为豹斑白云岩发生了两期白云石化.一期是通过渗透回流生成泥晶白云岩;二期是在浅埋藏环境下,随着白云石化流体继续供给,虫孔中的泥晶白云石更易继续生长或发生重结晶,形成由细粉晶白云岩构成的斑块.因此,掘穴生物活动形成的潜穴,是造成不均匀白云岩化,形成豹斑的重要原因. 相似文献
9.
Based on the Simplified Bishop Method, the minimum safety factor of ice slope both with and without tension cracks is calculated in combination with triaxial compression tests. It is found that there exists a critical depth for each crack. Then, factors influencing ice slope stability such as slope ratio, slope height, ice cohesion, internal friction angle, unit weight and temperature were analyzed. Meanwhile, a regression equation between the aforementioned factors and safety factor is obtained, with which sensitivity analysis is carried out. The performance function is built in combination with random distribution of physical and mechanical parameters to analyze the reliability index. The Advanced First Order Second Moment Method is employed on the solution to the performance function. The one-way coupling system of ice slope stability is therefore formed based on safety factor and reliability index. Finally, an illustrated example of ice slope is provided, which shows that failure probability is relatively high, up to 6.18%, although safety factor is 2.77. Thus, it is objective and reasonable to apply the coupled system method to the slope stability rating. 相似文献
10.
以实现对极轨气象卫星应用系统健康程度进行综合评价为目的,提出结合主观分析的层次分析法(Analytic Hierarchy Process,AHP)和客观分析的熵权法(Entropy Weight,EW)确定待评价系统指标值的综合权重,再采用逼近理想解排序法(Technique for Order Preference by Similarity to an Ideal Solution,TOPSIS)对系统的指标进行多角度评价排序来作为最终评价结果。本文根据连续5个月3颗极轨气象卫星在实际业务系统运行中异常指标样本进行实证分析。结果表明该方法较为全面考虑了影响应用系统的多种因素,避免了单一判据的局限性,并对各指标的重要性进行综合对比分析,使得评价结果更科学准确,可以作为构建极轨气象卫星应用系统健康程度评价指标体系的一种方法。 相似文献