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946篇 您的检索式:作者名="Edwards R L"
    题名 作者 年代 出处 被引量
1南京葫芦洞石笋δ^(13)C对冰期气候的复杂响应与诊断显示文摘文中重建了南京葫芦洞内距今75~10ka期间7支石笋δ13C的时间变化序列,δ13C曲线在重叠时段均具有一致性波动形式.在最后一个冰期/间冰期旋回,δ13C值变化幅度达6‰,反映了C3/C4植被类型变化对δ13C的主控作用.然而,在末次冰期格陵兰冰心记录的DO暖事件时(千年尺度),δ13C与指示降水变化的δ18O呈反相关,主要反映了快速渗水条件下洞穴岩溶水对土壤CO2溶解量的降低.据同期生长石笋δ13C和δ18O对比分析,石笋碳同位素动力分馏程度与生长速率有关.进一步研究发现,本区末次冰消期植被类型变化滞后于降水变化约700年.孔兴功 汪永进 吴江滢 Cheng Hai L R Edwards Wang Xianfeng 2005中国科学(D辑)2005,35,11:24
2贵州荔波地区2000年来石笋高分辨率的气候记录显示文摘通过对荔波董哥洞石笋进行高精度的ICP-MS或TIMS-U系测年和碳、氧同位素分析,建立了荔波地区2 300a B.P.来高分辨率的古气候变化的时间序列。研究结果表明,贵州荔波地区2 300a B.P.以来石笋记录的季风气候变化,大致可分为8个气候(亚)期:①2300~1 800a B.P.为降温期,显示东亚夏季风减弱,东亚冬季风增强,气候干旱寒冷;②1 800~1 080a B.P.气温有所回升,显示东亚冬季风缓慢减弱,东亚夏季风有所回升,表现为半湿润的温凉气候期;③1 080~680a B.P.为降温期,气温再次下降,显示东亚冬季风再次增强,但降水相对增大,表现为寒冷湿润的气候期,是气候变化的关键转折时期;④680~550a B.P.温暖期,显示东亚夏季风再次增强,气温升高,降水增大,表现为温暖湿润的气候期。⑤550~400a B.P.寒冷期,显示东亚冬季风快速增强,气温下降,表现为寒冷湿润的气候环境,是近1 000年以来最冷的时期;⑥400~364a B.P.温凉期,显示东亚夏季风有所增强,气温有所回升,表现为温凉湿润气候环境;⑦364~324a B.P.冷凉期,显示东亚夏季风有所减弱,气温有所下降,表现为冷凉湿润气候环境;⑧324a B.P.至今,气候相对波动期,同位素记录曲线呈锯齿状波动,在其内包括若干个冷凉半湿润、冷湿的气候变化亚阶段。根据荔波董哥洞石笋的高分辨率的古气候变化的连续记录,揭示了荔波地区2 300a B.P.以来的一些百年尺度的重大气候事件——干旱寒冷期、隋唐温暖期(或小温暖期)、小寒冷期以及一些十年尺度的降水、温度变化。石笋记录的这种百年、十年尺度的突发性气候变化事件,与冰芯记录极为相似,反映低纬度地区石笋记录的季风气候与高纬度及北极地区的气候具有极好的相关性,这对于认识现代气候系统变化以及对未来十年一百年尺度的气候预测和演化的驱动机制,具有重要的科学意义。张美良 程海 林玉石 覃嘉铭 朱晓燕 冉景丞 杨琰 陈会明 Edwards R L 2006沉积学报2006,24,3:19
3High-resolution stalagmite δ13C record of soil processes from southwestern China during the early MIS 3显示文摘Knowledge of the evolution of pedogenic processes in the carbonate area is important to understand the dynamics of rock desertification.A precisely-dated stalagmite δ13C record between 61.3 and 50.5 ka BP from southwestern China,potentially related to soil biogenic CO2 production,shifts within a narrow range between -9‰ and -7‰,and exhibits a prominent cycle of 350-470 a,independent of the Asian monsoon changes.This indicates that a threshold effect might control the amplitude of calcite δ13C variability,likely associated with the vertical soil loss in the carbonate area.The periodic δ13C changes reflect that the loss/recovery of soil cover can operate on centennial scale.Thus,the rock desertification in southwestern China might at least initiate 60 ka ago and should be of natural origin.LIU DianBing WANG YongJin CHENG Hai EDWARDS R L 2013Chinese Science Bulletin2013,58,7:5
4贵州七星洞石笋记录的一次强降水事件的探讨显示文摘全球变暖、极端事件频发背景下,研究极端事件发生规律,并准确预测未来极端事件的发生,已经成为目前极端事件研究的现实而紧迫的任务。利用地质载体重建过去极端事件的发生规律是极端事件研究的重要手段。本研究以贵州七星洞两个具有相似沉积特征的文石-方解石石笋对过去发生的一次强降水事件进行了探讨。主要认识有:(1)七星洞QX1和QX6石笋分别记录的黄褐色纹(微)层具有相似的沉积特征,为强降水携带粘土沉积形成;(2)两个石笋黄褐色纹(微)层发生的时间经推算在误差范围内一致,发生在公元(1868±1)年;(3)此次强降水事件发生的气候背景为:长时间的干旱导致洞顶植被覆盖和土壤湿度减小,而1869年的雨季多雨,在强降水携带下粘土沉积于石笋表面形成纹(微)层。此次事件的研究为东亚季风区极端降水事件研究提供了新的思路。殷建军 林玉石 唐伟 程海 EDWARDS R L 2016地球学报2016,37,3:4
5Metastatic recurrence to a solitary lymph node four years after hepatic lobectomy for primary hepatocellular carcinoma显示文摘This report describes a patient that developed recurrent metastatic hepatocellular carcinoma(HCC) to a suprapancreatic lymph node four years after being treated for primary HCC via complete left hepatectomy. Metastatic HCC was proven by pathologic confirmation. The report addresses the role of surgical resection as a treatment modality for recurrent HCC to solitary lymph nodes. The role of biological chemotherapy as adjuvant treatment is also addressed.Michael L Caparelli Nathan J Roberts Timothy S Braverman Robert M Stevens Edward R Broun Shyam Allamaneni 2016World Journal of Hepatology2016,8,23:2
661~50kaBP亚洲季风百年尺度气候振荡的黔西南石笋记录显示文摘12个U/Th年龄测试结果显示,黔西南普安县雾露洞长度分别为667mm和830mm的两支石笋覆盖了61~50kaBP时段。据两支石笋999个δ18O数据建立了平均分辨率达15年的亚洲夏季风强度变化序列。雾露洞δ18O记录揭示了4个振幅达1.7‰的千年尺度季风增强事件,对应于格陵兰冰心DO17—DO14事件。在总体特征上,该记录峰谷振荡特征及振幅与贵州董歌洞、南京葫芦洞记录一致,进一步证实亚洲季风区大气降水同位素组成变化在大范围空间内具有一致性。在百年尺度上,亚洲季风区石笋δ18O清晰记录了MIS3早期6个DO亚旋回事件,而且在更短时间尺度上具有类似高纬气温振荡特征。这种低纬季风系统与北高纬气候变化的耦合关系表明,大气环流快速重组和传输可能是连接高低纬DO旋回及亚旋回气候变化的主要纽带。王军彬 孔兴功 程海 汪永进 R L Edwards 2008海洋地质与第四纪地质2008,28,5:2
7Efficient photon coupling from a diamond nitrogen vacancy center by integration with silica fiber显示文摘A central goal in quantum information science is to efficiently interface photons with single optical modes for quantum networking and distributed quantum computing.Here,we introduce and experimentally demonstrate a compact and efficient method for the low-loss coupling of a solid-state qubit,the nitrogen vacancy(NV)center in diamond,with a single-mode optical fiber.In this approach,single-mode tapered diamond waveguides containing exactly one high quality NV memory are selected and integrated on tapered silica fibers.Numerical optimization of an adiabatic coupler indicates that near-unity-efficiency photon transfer is possible between the two modes.Experimentally,we find an overall collection efficiency between 16%and 37%and estimate a single photon count rate at saturation above 700 kHz.This integrated system enables robust,alignment-free,and efficient interfacing of single-mode optical fibers with single photon emitters and quantum memories in solids.Rishi N Patel Tim Schröder Noel Wan Luozhou Li Sara L Mouradian Edward H Chen Dirk R Englund 2016Light(Science & Applications)2016,5,1:2
8^238U,^234U and ^232Th in sea water显示文摘Chen J H Edwards R L Wasserburg G J 1986Earth and Planetary Science Letters1986,,80:1
9Control of the sex ratio at full termin the rabbit by transferring sexed blastocysts显示文摘Gardner R L Edwards R G 1968Nature1968,218,:1
10A new technique for measuring the mechanical properties of thin films 显示文摘Shape W N Bin Y Edwards R L 1997Journal of Microelectromech System1997,,6:1
11Analysis of stained objects in histological sections by spectral imaging and differential absorption显示文摘 Woemer B M Edwards D A 1999Journal of Histochemistry & Cytochemistry1999,47,10:1
12Measurement ofinterfacial dilational viscosity at high rates of interface expansion using the maximum bubble pressure method 1:Gas-liquid interface显示文摘 Edwards D A Wasan D T 1992Journal of Colloid and Interface Science1992,148,1:1
13A test of climate, sun, and culture relationships from an 1 810 year Chinese ca- ve record显示文摘Zhang P Z Cheng H Edwards R L 2008Science2008,322,:1
14Researchin stress, coping and health Theoretical and methedologicalissues显示文摘Edwards J R Cooper C L 1988Psychological Medicine1988,18,:1
15Timing, duration, and transitions of the last interglacial asian monsoon 显示文摘Yuan D X Cheng H Edwards R L 2004Science2004,304,:1
16^238U-^234U -^230Th-^232Th systematics and the precise measurement of time over the past 500 000 years显示文摘Edwards R L Chen J H Wasserburg G J 1986Earth and Planetary Science Letters1986,81,:1
17The application of a piezoelectric bar gauge to shock tube studies显示文摘Edwards D H Davies L Lawrence T R 1964J Sci Instrum1964,64,:1
18The holocene asian monsoon: links to solar changes and North Atlantic climate 显示文摘Wang Y J Cheng H Edwards R L 2005Science2005,308,:1
19The half-lives of uranium-234 and thorium-230显示文摘Cheng H Edwards R L Hoff J A 2000Chem Geol2000,169,:1
20Metagenomic analysis of the microbial community associated with the coral Porites astreoides显示文摘Wegley L Edwards R Rodriguez-Brito B 2007Envir Microb2007,9,:1
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