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Characterization of plastic flow in two Zr-based bulk metallic glasses

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Science China(Technological Sciences) 2006年第4期49卷 414-424页

作者： XING Dongmei1,2. ZHANG Taihua1, LI Weihuo3.& WEI Bingchen3.1. State Key Laboratory of Nonlinear Mechanics (LNM), {2. of Mechanics, Chinese Academy of Sci- ences, Beijing 100080, China 2. College of Physics and Electronic Information Science, tianjin Normal University, tianjin 3.0074, China 3. National Microgravity Laboratory, {2. of Mechanics, Chinese Academy of Sciences, Beijing 100080, China 1. State Key Laboratory of Nonlinear Mechanics (LNM) Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China 2. College of Physics and Electronic Information Science Tianjin Normal University Tianjin 300074 China 3. National Microgravity Laboratory Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

Plastic deformation behaviors of Zr65Al10Ni10Cu15 and Zr52.5Al10Ni10Cu15Be12.5 bulk metallic glasses (BMGs) are studied by using the depth-sensing nanoindentation, microindentation and uniaxial compression. The Be-containing BMG exhibits a signifi- cantly improved overall plastic strain compared with the Be-free alloy during compressive tests. Both BMGs show a loading-rate-dependent serrated flow during nanoindentation measurements, but the Be-containing alloy exhibits a much lower critical loading rate for the disappearance of the serration than the Be-free BMG. The shear band patterns de- veloped during plastic deformation are investigated by microindentation technique, wherein much higher shear band density is found in the Be-containing alloy than in the Be-free alloy, indicating an easier nucleation of shear bands in the former BMG. The dif- ference in the plastic deformation behavior of the two BMGs can be explained by a free volume model.

关键词： Bulk metallic glass, plastic deformation, shear band, nanoindentation.

Redetermination of the Crystal Structure of Vesignieite

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Acta Geologica Sinica(English Edition) 1991年第2期65卷 145-151页

作者： Ma Zhesheng He Ruilin Zhu Xiaoling China University of Geosciences institute of geology and{2. {3., Shaanxi institute of{2. Depostis, Chinese Academy of Geological Sciences China University of Geosciences China

Vesignieite, Cu_3.a(VO_4)_2.OH)_2. crystallizes in space group C_2./ m with a°=1.02.0(2., b°=0.5911(1),c°=0.7711(2.nm and β=116.42.3.°. The intensity data were collected with the RIGAKU RASA-IISsingle-crystal four-circle diffractometer. The structure was determined by Patterson and Fourier methods andrefined by the least-square technique to a final R index of 0.051 for 614 independent diffraction points with|F? |>3.|F?|. The crystal structure analysis shows that vesignieite has a layer structure parallel to (001). The powder diffraction lines were reindexed.

关键词： Redetermination of the Crystal Structure of Vesignieite

Randomization of protein encoding gene during species evolution

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Chinese Science Bulletin 1998年第4期43卷 299-303页

作者： GE Weiwen 1 and HE Fuchu 2.1. institute of Hygiene and Environment Medicine, tianjin {2.0050, China 2. institute of Radiation Medicine, Beijing 100850, China institute of Hygiene and Environment Medicine Tianjin China institute of Radiation Medicine Beijing China

Employing chi_square test, the authors observed the bias of 4 kinds of bases’ locating in 3.codon positions in gene sequence, and proved that there is a positive correlation between higher chi_square value and protein coding structure. By this, the observation that genes undergo progressive reduction in chi_values along evolution direction will reflect the progressive randomization of gene structures and the loss of the characteristics of protein coding sequences. The result proposed that during the evolution of life, genes are unexpectedly degenerating.

关键词： chi_square test gene sequence randomization evolution.

Fossil fauna and *** from core QC2.in the South Huanghai Sea

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Acta Oceanologica Sinica 1990年第4期9卷 561-578页

作者： Zhu Xionghua and Lin Hemao institute of Marine geology, Ministry of geology and {3. resources, Qingdao, China Inst. of Marine geology Ministry of Geology & Mineral Resources Qingdao China

According to palaeoenvironmental analysis on the fossil fauna dominated by Foraminifera and Ostracoda, core QC2.contains 8 marine transgressive beds, called (from up to bottom) Transgressive Beds Ⅰ,Ⅱ, Ⅲ, …,Ⅷ respectively. Together with dating data, the transgressive sequence since 1. 7 Ma B. P. has been established, indicating that the core went through middle and late Early Pleistocene, early and late Middle Pleistocene, early and late (Substages A and B) Late Pleistocene and the Holocene transgressions. Within these 8 transgressions, late Middle Pleistocene, early Late Pleistocene and the Holocene transgressions-had rather strong activities proved by shallow sea (of 50 or 2.-50 m water depth) deposits in the prime, while 2.of the 8, during middle Early Pleistocene and late Late Pleistocene (Substage A), were much weaker only with supratidal deposits. The transgressive cycles also differ from each other. Transgressions in the Holocene and in Substage B of late Late Pleistocene are made up of 3.and 2.subcycles of marine ingressions and regressions respectively, but most transgressions only have a single ingressive or regressive sequence. With the core, some important problems concerning, the study of Quaternary transgression such as correlation of transgressive beds and climatic periods and dating of the transgressive beds are discussed in this paper.

关键词： Fossil fauna and transgressive.sequence from core QC2.in the South Huanghai Sea core QC

Determination of tectonic background for sedimentary basin from sandstone geochemistry

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Chinese Science Bulletin 1998年第14期43卷 1191-1196页

作者： SHAO Lei 1, K. Stattegger 2.and LI Wenhou 3.1. Laboratory of Marine geology, Tongji University, Shanghai 2.0092. China 2. Geological and Paleontological {2., University of Kiel, 2.118 Kiel, Germany 3. Department of geology, Northwest Unive Laboratory of Marine geology Tongji University Shanghai China Geological and Paleontological institute University of Kiel Kiel Germany Department of geology Northwest University Xi’an China

The chemical composition of sedimentary rocks is mainly controlled by source rocks. Through examining chemical composition of terrigenous rocks, the tectonic evolution of a sedimentary basin can be modeled. The Turpan Basin belongs to a continental sedimentary basin and its source rocks are derived from the upper continental crust.

关键词： sedimentary rock geochemistry basin analysis Turpan Basin.

Numerical modelling of sand beach evolution around coastal structures

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Acta Oceanologica Sinica 2000年第2期19卷 127-136页

作者： Zhang Haiwen1 Tao Jianhua2.(1. Department of Mechanics, tianjin University, tianjin {2.0072. China. Present address: tianjin {{2. of Urologic Surgery, tianjin {2.02.1, China 2. Department of Mechanics, tianjin University, tianjin {2.0072. China) tianjin Inst. of Urologic Surgery Tianjin 300211 China

A systematic study of waves, nearshore currents and sediment transport related to the coastal evolution of sand beach under the action of wave, has been carried out. On the basis of the re sults, a numerical model of sand beach evolution around coastal structures has been established. To pre dict the bed topography, the sediment transport rates of bedload and suspended load under the action of wave and nearshore current as well as the effects of wave on the sediment are considered. The sand beach evolutions caused by a breakwater and a settled ship near the shore are simulated.

关键词： Wave nearshore current Sand beach evolution

A New Fauna——Qinghezhen Fauna——from the Northern Margin of the North China Platform

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Acta Geologica Sinica(English Edition) 1990年第4期64卷 443-459,468-470页

作者： Liu Xiaoliang Wang Dongfang Shenyang institute of geology and{2. {3., Chinese Academy of Geological Sciences Yue Zhao Shenyang institute of geology and{2. {3. Chinese Academy of Geological Sciences

In the Inner Mongolia axis and Jiaoliao anteclise along the northern margin of the North China *** has been found that the strata formerly considered as Archaean and Proterozoic are in fact an ophiolite suitesimilar to the Early Palaeozoic Ondor Sum Group in the Northern Geosyncline region of China. The stratahave been named in northern Liaoning as the Qinghezhen Group. The emphasis of this paper is on the discus-sion of the simall shelly fossils found in the siliceous rocks in the upper part of the Qinghezhen Group. Thisophiolite suite stretches in an E-W direction for about 1000 km along the northern margin of the North ChinaPlatform. in which 15 fossil localities with stable stratigraphic horizons have been discovered. In this paper. 4types. 7 genera (including 5 new ones) and 10 species (including 8 new ones and 1 new subspecies) aredescribed, which are collectively referred to as the Qinghezhen Fauna. The characteristics of these fossils are:shell form simple. the maximum length not exceeding 4 mm. with obvious shell wall and wall ornaments. TheQinghezhen Fauna is comparable in shell structure of some genera and species with the Meishucun Fauna inSouth China, but differs from the latter in having only monotonous fossil groups developed in a distinctly va-ried ecological environment. The two faunas may belong to the same evolutionary stage of the Early Cambrianbut have developed parallelly in different regions. The existence of the Qinghezhen Fauna represents an impor-tant biological event in the Early Cambrian in the Northern Geosyncline region of China. The discovery of theQinghezhen Fauna will bring new knowledge and profound influence to a series of problems on basic geologyand mineral deposit prospecting such as the Cambrian faunas. biogeographical povincialism in China and thegeotectonic features of the northern margin of the North China Platform.

关键词： A New Fauna from the Northern Margin of the North China Platform

晚期消化道肿瘤病人对药物临床试验认知的质性研究

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护理研究 2024年第1期38卷 157-160页

作者：王秋月李艳天津医科大学肿瘤医院、国家恶性肿瘤临床医学研究中心、天津市“肿瘤防治”重点实验室天津市恶性肿瘤临床医学研究中心天津300060

目的:调查晚期消化道肿瘤病人对药物临床试验的认知与看法。方法:采用质性研究方法,通过半结构式访谈对12.首次接受药物临床试验治疗的晚期消化道肿瘤病人进行个体深入访谈,运用内容分析法分析资料。结果:首次接受药物临床试验治疗的... 详细信息

目的:调查晚期消化道肿瘤病人对药物临床试验的认知与看法。方法:采用质性研究方法,通过半结构式访谈对12.首次接受药物临床试验治疗的晚期消化道肿瘤病人进行个体深入访谈,运用内容分析法分析资料。结果:首次接受药物临床试验治疗的晚期消化道肿瘤病人对药物临床试验的认知主要分为3.主题,即对临床试验充满担忧(疗效不确定性、代入为牺牲品、担心不良反应),从临床试验中重拾希望(希望延长生命、减轻经济负担、渴望专业指导),对临床试验持中立态度。结论:晚期消化道肿瘤病人在接受临床试验治疗时面临多种问题,护理人员应给予针对性指导和帮助,以促进病人积极完成治疗。

关键词：消化道肿瘤晚期肿瘤药物临床试验认知质性研究

Chronological record of the Early Mesozoic underplating in the northern margin of North China—U-Pb chronometry of zircons in the Late Mesozoic andesite from Western Liaoning

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Progress in Natural Science:Materials International 2007年第8期17卷 943-947页

作者： Shao ji'an~(1,2.*) Zhang Hongfu~2.Liu Xiaoming~3.Li Zhitong~4 (1.School of Earth and Space Sciences,Peking University,Beijing 100871,China 2.institute of {2. and Geophysics and Key Laboratory of {2. {3.,Chinese Academy of Sciences,Beijing 10002.,China 3.Key Laboratory of Continental Dynamics,Northwestern University,Xi'an 710069,China 4.institute of {2. and {2. {3. of Shenyang,Shenyang 11003.,China) [a]School of Earth and Space Sciences Peking University Beijing China [b]Laboratory of mineral resources Chinese Academy of Sciences Institute of Geology and Continental Dynamics Beijing China [c]Key Laboratory of Continental Dynamics Northwestern university Xi'an China [d]institute of geology and{2. {3. of Shenyang Shenyang China

Cathodoluminescence spectroscopic analysis of zircons in the uppermost sanukites of the early Cretaceous Yixian Forma- tion in Western Liaoning reveals zoning structures of the zircons in the volcanic rocks. LA-ICP-MS chronometry shows that the central part of the zircons is remnant zircon with a U-Pb dating of 2.4 Ma,which is consistent with the age of the Early Mesozoic underplating granulites,and that the periphery is zircon crystallizing out of the host magma with a U-Pb dating of 116 Ma,which is highly consistent with the Ar-Ar dating of the host volcanic *** of the clinopyroxenes xenocrystals in the sanukites are similar to those of the clinopyroxenes in the underplating granulites,indicating that the granulites accreted to the lower crust in the Early Mesozoic have been reformed and disrupted by the upwelling diapers of the asthenosphere and taken part in formation of the sanukites in the Late Mesozoic.

关键词： northern margin of North China Mesozoic volcanic rock U-Pb chronometry of zircon underplating granulite