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Integrated fission track and (U-Th)/He analysis is carried out on 6 apatite and 6 zircon samples from a near vertical section in The Tiantangzhai region at the core of the present Dabieshan orogen. The result shows that the region experienced cooling/exhumation during the Late Cretaceousand Early Tertiary period. Age-elevation relationships for different dating systems and different minerals suggest a pulse of rapid exhumation at ~110 Ma before present, preserved in the structurally highest samples. At lower elevations, ages begin to decrease with decreasing elevation, suggesting lower exhumation rates since 90 Ma. Two periods of different exhumation rates are identified since 90 Ma. The average apparent exhumation rate for the period of 43.4—22.5 is 0.062 km/Ma, whereas that for the period of 76.4—47.4 Ma is 0.039 km/Ma.  相似文献   
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对大别山造山带的岳西-罗田核部及其南北两翼的13个锆石样品的(U-Th)/He测年结果表明,各样品锆石(U-Th)/He年龄介于85~155Ma之间,核部He年龄为85~107Ma,两翼年龄介于114~155Ma之间,反映岳西-罗田穹隆实际上是一个核部比两翼要热得多的热穹隆,形成大别穹状核杂岩这一热伸展事件可能持续到85Ma左右,核部岩石自85Ma以来的剥露量要比两翼多1528.8m..  相似文献   
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利用光纤光栅实现压力和温度同时测量   总被引:5,自引:0,他引:5  
结合光纤光栅弹簧管压力传感器的结构特点 ,在悬臂梁的上下两面分别粘贴两个应力和温度灵敏系数基本相同的光纤光栅 ,通过分别测量光纤光栅对的波长位移 ,实现了压力和温度的同时测量 ,压力和温度测量的分辨率分别为 0 .1 4 MPa和 0 .5℃ .  相似文献   
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Summary Small amounts of 7-hydroxy-4-methoxyisoflavone (formononetin) and ferulic acid were isolated from liquorice root and identified by spectral properties and degradation.

Als Mitteilung I gilt Naturwiss.51, 193 (1964).  相似文献   
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对采自大别山主峰天堂寨地区高差约1.4 km的垂直剖面内不同高程上的6个样品进行了锆石/磷灰石的(U-Th)/He和裂变径迹分析, 分析结果表明天堂寨地区在晚白垩世~早第三纪期间仍处在冷却剥露过程之中. 垂直剖面上各样品的各个测年体系的年龄-高程关系表明, 在距今110 Ma时存在一个快速的冷却剥露时期; 从距今90 Ma开始, 各样品的年龄随着高程的降低而减少, 可以进一步识别出两个具有不同平均视剥露剥蚀速率的时期. 43.4~22.5 Ma间的平均视剥露剥蚀速率为0.062 km/Ma, 76.4~47.4 Ma间的平均视剥露剥蚀速率为0.039 km/Ma.  相似文献   
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To identify susceptibility loci for classical Hodgkin's lymphoma (cHL), we conducted a genome-wide association study of 589 individuals with cHL (cases) and 5,199 controls with validation in four independent samples totaling 2,057 cases and 3,416 controls. We identified three new susceptibility loci at 2p16.1 (rs1432295, REL, odds ratio (OR) = 1.22, combined P = 1.91 × 10(-8)), 8q24.21 (rs2019960, PVT1, OR = 1.33, combined P = 1.26 × 10(-13)) and 10p14 (rs501764, GATA3, OR = 1.25, combined P = 7.05 × 10(-8)). Furthermore, we confirmed the role of the major histocompatibility complex in disease etiology by revealing a strong human leukocyte antigen (HLA) association (rs6903608, OR = 1.70, combined P = 2.84 × 10(-50)). These data provide new insight into the pathogenesis of cHL.  相似文献   
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Reiners PW  Ehlers TA  Mitchell SG  Montgomery DR 《Nature》2003,426(6967):645-647
Past studies of tectonically active mountain ranges have suggested strong coupling and feedbacks between climate, tectonics and topography. For example, rock uplift generates topographic relief, thereby enhancing precipitation, which focuses erosion and in turn influences rates and spatial patterns of further rock uplift. Although theoretical links between climate, erosion and uplift have received much attention, few studies have shown convincing correlations between observable indices of these processes on mountain-range scales. Here we show that strongly varying long-term (>10(6)-10(7) yr) erosion rates inferred from apatite (U-Th)/He cooling ages across the Cascades mountains of Washington state closely track modern mean annual precipitation rates. Erosion and precipitation rates vary over an order of magnitude across the range with maxima of 0.33 mm yr(-1) and 3.5 m yr(-1), respectively, with both maxima located 50 km west (windward) of the topographic crest of the range. These data demonstrate a strong coupling between precipitation and long-term erosion rates on the mountain-range scale. If the range is currently in topographic steady state, rock uplift on the west flank is three to ten times faster than elsewhere in the range, possibly in response to climatically focused erosion.  相似文献   
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