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Early Cretaceous Tectonics and Evolution of the Tibetan Plateau

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Acta Geologica Sinica(English Edition) 2016年第3期90卷 847-857页

作者： WU Zhenhan ZHAO Zhen Patrick j. BAROSH YE Peisheng Chinese Academy of Geological Sciences Beijing 100037 China P.j. Barosh andAssociates 103 Aaron Ave. Bristol RI 02809 USA Institute of Geomechanies Chinese Academy of Geological Sciences Beijing 100081 China

Selected geological data on Early Cretaceous strata, structures, magmatic plutons and volcanic rocks from the Kunlun to Himalaya Mountains reveal a new view of the Early Cretaceous paleo-tectonics and the related geodynamic movement of the Tibetan Plateau. Two major paleo- oceans, the Mid-Tethys Ocean between the Qiangtang and Lhasa blocks, and the Neo-Tethys Ocean between the Lhasa and Himalayan blocks, existed in the Tibetan region in the Early Cretaceous. The Himalayan Marginal and South Lhasa Seas formed in the southern and northern margins of the Neo- Tethys Ocean, the Central Tibet Sea and the Qiangtang Marginal Sea formed in the southern and northern margins of the Mid-Tethys Ocean, respectively. An arm of the sea extended into the southwestern Tarim basin in the Early Cretaceous. Early Cretaceous intensive thrusting, magmatic emplacement and volcanic eruptions occurred in the central and northern Lhasa Block, while strike- slip formed along the Hoh-Xil and South Kunlun Faults in the northern Tibetan region. Early Cretaceous tectonics together with magmatic K20 geochemistry indicate an Early Cretaceous southward subduction of the Mid-Tethys Oceanic Plate along the Bangoin-Nujiang Suture which was thrust ~87 km southward during the Late Cretaceous-Early Cenozoic. No intensive thrust and magmatic emplacement occurred in the Early Cretaceous in the Himalayan and southern Lhasa Blocks, indicating that the spreading Neo-Tethys Oceanic Plate had not been subducted in the Early Cretaceous. To the north, terrestrial basins of red-beds formed in the Hoh-Xil, Kunlun, Qilian and the northeastern Tarim blocks in Early Cretaceous, and the Qiangtang Marginal Sea disappeared after the Qiangtang Block uplifted in the late Early Cretaceous.

关键词： Early Cretaceous paleo-tectonics subduction of the oceanic plate K20 geochemistry of granites Bangoin-Nujiang Suture the Tibetan Plateau

Paleoenvironments and geochemistry across a continuous Permian-Triassic boundary section at Bukk Mountains,Hungary

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Geoscience Frontiers 2021年第3期12卷 214-233页

作者： M.E.Brookfield j.C.Williams A.G.Stebbins School for the Environment University of MassachusettsBostonMA 02125USA School of Earth Sciencec The Ohio State UniversityColumbusOH 43210USA

The Bálvány North Permian-Triassic boundary sediments were deposited on a carbonate platform in the tropical part of the western Paleo Tethys *** overall elemental geochemistry of the detailed two-metre-thick section across the boundary that we studied shows that the clastic content of the sediments came from dominantly silica-rich continental sources though with some more silica-poor inputs in the uppermost Permian and lowest Triassic limestones as shown by Ni/Al and Nb/Ta *** inputs bracket,but do not coincide with,the main extinctions and associated C,O and S *** aridity at the Permian-Triassic boundary with increased wind abrasion of suitable Ti-bearing heavy minerals accounts for both the high Ti/Al and Ti/Zr *** geochemical redox proxies suggest mainly oxic depositional conditions,with episodes of anoxia,but with little systematic variation across the Permian-Triassic extinction *** lack of consistent element geochemical changes across the Permian-Triassic boundary occur not only in adjacent shallower-water marine sections,and in other marine sections along the SW Tethys margin such as the Salt Range sections in Pakistan,but also in deeper shelf and oceanic sections,and in non-marine African and European continental *** the absence of significant changes in physical environments,chemical changes in the atmosphere and oceans,reflected in various isotopic changes,drove the Permian-Triassic extinctions.

关键词： Permian-Triassic boundary Paleoenvironments geochemistry Hungary Bukk

Continuous-wave terahertz diffraction tomography for measuring three-dimensional refractive index maps

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Chinese Optics Letters 2021年第12期19卷 150-155页

作者：王大勇金晓宇赵洁王云新戎路 john j.Healy College of Physics and Optoelectronics Faculty of ScienceBeijing University of TechnologyBeijing 100124China Beijing Engineering Research Center of Precision Measurement Technology and Instruments Beijing 100124China Beijing-Dublin International College Beijing University of TechnologyBeijing 100124China

Three-dimensional(3D)refractive index(ri)distribution is important to reveal the object’s inner *** implemented terahertz(THz)diffraction tomography with a continuous-wave single-frequency THz source for measuring 3D ri *** off-axis holographic interference configuration was employed to obtain the quantitative scattered field of the object under each rotation *** 3D reconstruction algorithm adopted the filtered backpropagation method,which can theoretically calculate the exact scattering potential from the measured scattered *** on the Rytov approximation,the 3D ri distribution of polystyrene foam spheres was achieved with high fidelity,which verified the feasibility of the proposed method.

关键词： diffraction tomography three-dimensional terahertz imaging three-dimensional reconstruction algorithm refractive index measurement

老虎与瘟疫:中国彝族诗人吉狄马加呼唤重组分裂的世界

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作家 2020年第10期 10-13页

作者： [爱沙尼亚]尤里·塔尔维特胡伟(译) 欧洲科学院塔尔图大学比较文学系不详

大约和21世纪的起始同步,随着他的祖国中国向更广阔的世界、向以数字/加密通信和产业为标志的科技进步的巅峰(重新)开放,吉狄马加(生于1961年)作为中国现代最蜚声国际的诗人之一脱颖而出。他的作品被详尽地译成外文,包括大小语种,他在... 详细信息

大约和21世纪的起始同步,随着他的祖国中国向更广阔的世界、向以数字/加密通信和产业为标志的科技进步的巅峰(重新)开放,吉狄马加(生于1961年)作为中国现代最蜚声国际的诗人之一脱颖而出。他的作品被详尽地译成外文,包括大小语种,他在搭建中国与世界之间的文化桥梁和创意对话(因为他每年都在本国各地组织重要的国际诗歌节)方面的功绩着实令人惊叹。

关键词：吉狄马加诗歌节科技进步加密通信彝族诗人中国与世界 21世纪

Investigation on Bio-gas as a Fuel in Spark Ignition Engine

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农业工程学报 1998年第1期 158-162页

作者：黄敬党Ｒ．Ｊ．Ｃｒｏｏｋｅｓ

以不同比例的天然气和二氧化碳气体混合物来模拟不同气源的生物质气并在一台改装后的Ｒｉ－ｃａｒｄｏＥ６四冲程单缸点燃式发动机试验机上进行试验。文中给出了燃烧这些燃料时发动机的动力性、经济性以及ＣＯ、ＴＨＣ、ＮＯｘ等排放数... 详细信息

以不同比例的天然气和二氧化碳气体混合物来模拟不同气源的生物质气并在一台改装后的Ｒｉ－ｃａｒｄｏＥ６四冲程单缸点燃式发动机试验机上进行试验。文中给出了燃烧这些燃料时发动机的动力性、经济性以及ＣＯ、ＴＨＣ、ＮＯｘ等排放数据。试验结果表明，生物质气中的二氧化碳能改善ＮＯｘ排放指标，但降低了功率和热效率。提高压缩比能有效的改善动力性和经济性，但同时也增加了ＮＯｘ和ＴＨＣ的排放量。采用稀燃技术可望兼顾二者的要求。

关键词：生物质气点燃式发动机代用燃料天然气

Germanium nanoislands grown by radio frequency magnetron sputtering: Annealing time dependent surface morphology and photoluminescence

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Chinese Physics B 2013年第9期22卷 600-604页

作者： Alireza Samavati Z.Othaman S.K.Ghoshal R.j.Amjad Ibn Sina Institute for Fundamental Science Studies Universiti Teknologi Malaysia Advanced Optical Material Research Group Department of PhysicsFaculty of ScienceUniversiti Teknologi Malaysia

Structural and optical properties of ～ 20 nm Ge nanoislands grown on Si（100） by radio frequency （ri） magnetron sputtering under varying annealing conditions are reported. Rapid thermal annealing at a temperature of 600 ℃ for 30 s, 90 s, and 120 s are performed to examine the influence of annealing time on the surface morphology and photoluminescence properties. X-ray diffraction spectra reveal prominent Ge and GeO2 peaks highly sensitive to the annealing time. Atomic force microscope micrographs of the as-grown sample show pyramidal nanoislands with relatively high-density （～ 10^11 cm^-2）. The nanoislands become dome-shaped upon annealing through a coarsening process mediated by Oswald ripening. The room temperature photoluminescence peaks for both as-grown （～ 3.29 eV） and annealed （～ 3.19 eV） samples consist of high intensity and broad emission, attributed to the effect of quantum confinement. The red shift （～ 0.10 eV） of the emission peak is attributed to the change in the size of the Ge nanoislands caused by annealing. Our easy fabrication method may contribute to the development of Ge nanostructure-based optoelectronics.

关键词： germanium nanoislands radio frequency magnetron sputtering photoluminescence surface mor-phology

明清时期来华耶稣会士对中国大黄的记述及其原因

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福建师范大学学报（哲学社会科学版） 2011年第2期 128-134页

作者：林日杖福建师范大学社会历史学院福建福州350108

明清时期,大黄在中西方都有着十分广泛而重要的用途。耶稣会士是明清时期来华西人的重要群体。耶稣会士对大黄的探索,是西方大黄认识史上的重要一环。记叙大黄的耶稣会士主要有利玛窦、庞迪我、曾德昭、卜弥格、南怀仁、利国安、巴多明... 详细信息

明清时期,大黄在中西方都有着十分广泛而重要的用途。耶稣会士是明清时期来华西人的重要群体。耶稣会士对大黄的探索,是西方大黄认识史上的重要一环。记叙大黄的耶稣会士主要有利玛窦、庞迪我、曾德昭、卜弥格、南怀仁、利国安、巴多明、德西迪里、汤执中等人,来自意大利、西班牙、葡萄牙及法国等欧洲国家。耶稣会士能够关注大黄,并留下有关记述,是多种因素共同作用的结果,既受时势的影响,也有教会方面的因素,还有耶稣会士个人的作用。相关记述推动了欧美对大黄的探索,促成大黄在西方社会产生广泛而深远的影响。

关键词：明清时期耶稣会士大黄中外关系

A Thickness Gauge for the Lithosphere Based on Ce/Yb and Sm/Yb of Mantle–Derived Magmatic Rocks

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Acta Geologica Sinica(English Edition) 2018年第6期92卷 2120-2135页

作者： WU Zhenhan Patrick j. BAROSH ZHANG Qichao WU jiwen YANG Yan Chinese Academy of Geological Sciences Beijing 100037China P.j.Barosh and Associates 103 Aaron Ave.BristolRI02809USA Institute of Karst Geology Chinese Academy of Geological SciencesGuilin 541004China

A new method for determining the partial melting depth of mantle-derived magma and lithospheric thickness in continental regions is derived from REE geochemistry. This effective technique uses variations in the Ce/Yb and Sm/Yb ratios found in mainly volcanic rocks in continental China. The ratios change with the depth of origin consistent with the correlation between lithospheric thickness and the Ce/Yb and Sm/Yb ratios found in oceanic basalt. These ratios increase exponentially with the depth of origin, the lithospheric thickness, of a wide variety of Cenozoic volcanic basalt and Paleozoic kimberlite in the North China Craton, northeastern China continent and vicinity. This functional relationship with depth is shown in a plot of the ratios that forms a concordia curve, which is closely expressed by formulas using 8–degree polynomials. These provide a more accurate gage in measuring the lithospheric thickness than the traditional geophysical methods. When applied to volcanic rock of different ages it also reveals how the thickness has changed over time and thus, greatly aids the understanding of the tectonic history. Relations between the COcontent, mineral reactions and pressure in the upper asthenosphere beneath the base of the lithosphere appears to affect the proportions of REE in partial melts and brings about a close correlation between lithospheric thickness and the Ce/Yb and Sm/Yb ratios in mantle–derived magmatic rock. This thickness gauge, for both continental and oceanic lithosphere, provides a new approach in analyzing the lithospheric thickness in different tectonic settings and geologic times.

关键词： Ce/Yb and Sm/Yb ratios mantle–derived magmatic rock lithospheric thickness correlation analysis North China Craton

Ethanol inhibits the motility of rabbit sphincter of Oddi in vitro

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World journal of Gastroenterology 2004年第23期10卷 3470-3474页

作者： Réka Sári Attila Pálv lgyi Zoltán Rakonczay jr Tamás Takács jános Lonovics László Czakó Péter Hegyi Zoltán Szilvássy First Department of Medicine Faculty of MedicineUniversity of Szeged H-6720Koranyi fasor 10Hungary Department of Pharmacology Medical University of Debrecen H-4032Nagyerdei krt98Hungary

AIM: The role of the sphincter of Oddi (SO) in ethanol (ETOH)-induced pancreatitis is controversial. Our aim was to characterise the effect of ETOH on basal and stimulated SO ***: SOs removed from white rabbits were placed in an organ bath (Krebs solution, pH7.4, 37℃). The effects of 2 mL/L, 4 mL/L, 6 mL/L and 8 mL/L of ETOH on the contractile responses of the sphincter were determined.1 SOs were stimulated with either 0.1μol/L carbachol, 1μol/L erythromycin or 0.1μol/L cholecystokinin (CCK).RESULTS: ETOH at a dose of 4 mL/L significantly decreased the baseline contractile amplitude from 11.98±0.05 mN to 11.19±0.07 mN. However, no significant changes in the contractile frequency were observed. ETOH (0.6%) significantly decreased both the baseline amplitude and the frequency compared to the control group (10.50±0.01 mN,12.13±0.10 mN and 3.53±0.13 c/min, 5.5±0.13 cycles(c)/min,respectively). Moreover, 0.8% of ETOH resulted in complete relaxation of the SO. Carbachol (0.1μol/L)or erythromycin (1μol/L) stimulated the baseline amplitudes (by 82% and 75%, respectively) and the contractile frequencies (by 150% and 106%, respectively). In the carbachol or en/thromydn-stimulated groups 2-6 mL/L of ETOH significantly inhibited both the amplitude and the frequency. Interestingly,a 4-5 min administration of 6 mL/L ETOH suddenly and completely relaxed the SO. CCK (0.1μol/L) stimulated the baseline amplitude from 12.37±0.05 mN to 27.40±1.82 mN within 1.60±0.24 min. After this peak, the amplitudede creased to 17.17±0.22 mN and remained constant during the experiment. The frequency peaked at 12.8±0.2 c/min,after which the constant frequency was 9.43±0.24 c/min throughout the rest of the experiment. ETOH at a dose of 4 mL/L significantly decreased the amplitude from 16.13±0.23 mN to 14.93±0.19 mN. However, no significant changes in the contractile frequency were observed. ETOH at a dose of 6 mL/L inhibited both the amplitudes and the frequencies in the CCK-stimulated gr

关键词：乙醇抑制作用运动性兔括约肌体外胰腺炎