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101.
102.
Watanabe M 《Nature》2003,424(6944):110-111
103.
Homogeneous climate variability across East Antarctica over the past three glacial cycles 总被引:1,自引:0,他引:1
Recent ice core studies have raised the disturbing possibility that glacial-interglacial climate changes may be non-uniform across Antarctica. These findings have been confined to records from the Ross Sea sector of the continent, but significant deviations in other areas would call into question the widely assumed validity of the climate record obtained from Vostok, East Antarctica, on large spatial scales. Here we present an isotopic profile from a core drilled at Dome Fuji, situated 1,500 km from Vostok in a different sector of East Antarctica. The two records show remarkable similarities over the past three glacial cycles (the extent of the Dome Fuji record) in both large-amplitude changes, such as terminations, interglacials and interstadials and more subtle glacial events, even when the origin of precipitation is accounted for. Our results indicate that Antarctic climate is essentially homogeneous at the scale of the East Antarctic Plateau, possibly as a consequence of the symmetry of the plateau and the adjacent ocean. 相似文献
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105.
本书是2005年3月3—6日在日本Ritsumeikan大学举行的第5届“随机过程及对数学金融的应用”国际学术会议的论文集。该会议始于2001年,每年1次,本次会议邀集了一些国际著名学者及日本数学金融界的几个新秀就随机过程及随机分析在金融数学中的一些应用作了综合讲演,涉及一些中心问题和前沿课题。[第一段] 相似文献
106.
107.
High-resolution record of Northern Hemisphere climate extending into the last interglacial period 总被引:4,自引:0,他引:4
Andersen KK Azuma N Barnola JM Bigler M Biscaye P Caillon N Chappellaz J Clausen HB Dahl-Jensen D Fischer H Flückiger J Fritzsche D Fujii Y Goto-Azuma K Grønvold K Gundestrup NS Hansson M Huber C Hvidberg CS Johnsen SJ Jonsell U Jouzel J Kipfstuhl S Landais A Leuenberger M Lorrain R Masson-Delmotte V Miller H Motoyama H Narita H Popp T Rasmussen SO Raynaud D Rothlisberger R Ruth U Samyn D Schwander J Shoji H Siggard-Andersen ML Steffensen JP Stocker T Sveinbjörnsdóttir AE Svensson A Takata M 《Nature》2004,431(7005):147-151
Two deep ice cores from central Greenland, drilled in the 1990s, have played a key role in climate reconstructions of the Northern Hemisphere, but the oldest sections of the cores were disturbed in chronology owing to ice folding near the bedrock. Here we present an undisturbed climate record from a North Greenland ice core, which extends back to 123,000 years before the present, within the last interglacial period. The oxygen isotopes in the ice imply that climate was stable during the last interglacial period, with temperatures 5 degrees C warmer than today. We find unexpectedly large temperature differences between our new record from northern Greenland and the undisturbed sections of the cores from central Greenland, suggesting that the extent of ice in the Northern Hemisphere modulated the latitudinal temperature gradients in Greenland. This record shows a slow decline in temperatures that marked the initiation of the last glacial period. Our record reveals a hitherto unrecognized warm period initiated by an abrupt climate warming about 115,000 years ago, before glacial conditions were fully developed. This event does not appear to have an immediate Antarctic counterpart, suggesting that the climate see-saw between the hemispheres (which dominated the last glacial period) was not operating at this time. 相似文献
108.
Macular corneal dystrophy type I and type II are caused by distinct mutations in a new sulphotransferase gene 总被引:8,自引:0,他引:8
109.
Estimation of soil respiration in a paddy ecosystem in the subtropical resion of China 总被引:1,自引:0,他引:1
REN XiuE WANG QinXue TONG ChengLi WU JinShui WANG KeLin ZHU YongLi LIN ZeJian WATANABE Masataka TANG GuoYong 《科学通报(英文版)》2007,52(19):2722-2730
Water vapor, energy exchange, and CO2 flux were measured continuously from 2003 to 2005 using the eddy covariance technique in a paddy ecosystem in the subtropical region of China. The CO2 fluxes at nighttime during fallow periods (from middle October to late April) were used to analyze the dynamics of soil respiration and its relationship with soil temperature, and to simulate the annual dynamics of soil respiration in paddy ecosystems. The variation of soil respiration showed a clear seasonal pattern. The soil respiration rates at night during the fallow periods were 52--398 mg· m^-2· h^-1, and exponentially correlated (P〈0.001) with soil temperatures at different depths of soil (5, 10, and 20 cm), particularly the temperature measured at a depth of 5 cm. Based on the simulated exponential equations developed, annual average soil respiration rates and total soil respiration of paddy soil in the subtropical region of China were estimated to be 178.5--259.9 mg· m^-2· h^-1 and 1.56--2.28 kg· m^-2· a^-1, respectively. The simulation equations can be applied to evaluating soil respiration in paddy ecosystems during the rice-growing season. 相似文献
110.
高层钢筋混凝土框架底层角节点抗震性能 总被引:1,自引:0,他引:1
由地震引起的高轴力及双向荷载使高层钢筋混凝土框架底层边节点剪切破坏后的角柱压溃危险度大幅度提高。该部位节点抗震性能研究十分重要。通过3个角节点试件在双向低周反复荷载作用下的受力性能试验,调查了高轴力、节点配箍量试验参数对节点破坏类型、变形特征及节点强度等节点抗震性能的影响及节点破坏后柱的竖向承压能力。首次提出双向荷载作用下节点抗剪强度计算的strut-truss立体计算模型并对该节点抗剪强度进行了定量数值解析。解析结果与试验结果较吻合。 相似文献