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Synchrotron radiation X-ray fluorescence (SR-XRF) approach was applied to analyzing of Chinstrap penguin ( Pygoscelis Antarctica) cortical bone. The method enabled the in situ determination of Ca and P concentrations and the Ca/P ratio in cortical bone. The preliminary results show that : ( 1 ) there is the bone site-related difference for Ca and P concentrations. The mean values for the investigated parameters ( on a dry-weight basis) are: 30.7% (Ca) and 14.9% (P) for the femoral cortical bone, 21.4% (Ca) and 11.5% (P) for wing cortical bone. (2) The variation for the Ca/P ratio in cortical bone is lower than those for Ca and P separately. This is in agreement with the previous report that the specificity of the Ca/P ratio is better than that of Ca and P concentrations and is more reliable for the diagnosis of bone disorders. The authors suggest that further studies be conducted to establish norreal values of Ca, P and Ca/P ratio for polar animals and provide a basis for the diagnosis of bone disorders. 相似文献
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通过对白集煤矿下石盒子组3煤的小型滑脱构造成因分析,找出了小型滑脱构造对煤层赋存变化的控煤作用,为矿井生产提供正确的地质资料。 相似文献
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本文简要介绍该领域研究的理论基础和获得的代表性成果,以及如何运用Sr-Nd同位素演化示踪技术探讨:区域基底和含矿层的供矿能力;水-岩交换性质和沉积环境;阐明成岩、成矿时水体介入和基岩参与程度;水源、岩源特征以及同位素交换平衡条件。为研究成矿环境和溶浸条件提供依据。 相似文献
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本文应用Sr,Nd,Pb同位素演化示踪获得:华南各地区中生代火山岩的同位素演化受区域古陆(基底)变质岩、早期改造衍生体和再循环陆壳制约;铀成矿同位素组成具有地壳来源性。燕山期大陆边缘增生作用,导致陆内下地壳岩浆活动及拉张裂陷等地壳运动,促成铀的迁移富集成矿。 相似文献
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三峡库区堆积层滑坡在季节性降雨和库水位周期波动的影响下呈现间歇性活动特征,滑坡活动强度与诱发因素作用强度和时间关系密切。以三峡库区白水河滑坡为例,分析了堆积层滑坡间歇性活动特征和诱发因素,发现降雨和库水位下降是滑坡变形的主要诱发因素。根据滑坡时序曲线特征,将滑坡累积位移分解为趋势项位移和周期项位移,采用多项式拟合的方法来预测趋势项位移,利用长短期记忆神经网络模型来预测周期项位移,并与极限学习机模型、广义回归神经网络模型的预测结果进行了对比分析,发现长短期记忆神经网络模型预测滑坡间歇性活动精度更高。 相似文献