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Synthesis of α-Bromine-Terminated Polystyrene Macroinitiator and Its Initiation of MMA Polymerization by ATRP

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Chemical Research in Chinese Universities 2000年第1期16卷 72-77页

作者： LIU Feng LIU Bing LUO Ning and YING Shengkang (The Laboratoric of Living Polymerization, East china University of Science and Technology, Shanghai 200237, P. R. china) LIU Qing (Research Institute of beijing Yanshan Petrochemical corporation, beijing 1 华东理工大学上海 200237 燕山石油化工公司研究院北京 102550

In the present paper the synthesis of block copolymers via the transformation from living anionic polymerization (LAP) to atom transfer radical polymerization (ATRP) was described. α-Bromine-terminated polystyrenes(PStBr) in the LAP step was prepared by using n-BuLi as initiator, tetrahydrofuran (THF) as the activator, α-methylstyrene (α-MeSt) as the capping group and liquid bromine (Br_2) as the bromating agent. The effects of reaction conditions such as the amounts of α-MeSt, THF, and Br_2 as well as molecular weight of polystyrene on the bromating efficiency (BE) and coupling extent (CE) were examined. The present results show that the yield of PStBr obtained was more than 93. 8% and the coupling reaction was substantially absent. PStBr was further used as the macroinitiator in the polymerization of methyl-methacrylate (MMA) in the presence of copper (I ) halogen and 2, 2' -bipyridine (bpy) complexes. It was found that the molecular weight of the resulted PSt-b-PMMA increased linearly with the increase of the conversion of MMA and the polydispersity was 1. 2-1.6. The structures of PStBr and P(St-b-MMA) were characterized by ~1H NMR spectra.

关键词： Atom transfer radical polymerization, Living anionic polymerization, Block copolymer, Macroinitiator, Bromation, α-Methylstyrene Capping reaction

Nuclear Energy—the Strategic Role and Sustainability in china

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工程科学（英文版） 2007年第4期5卷 2-9,58页

作者： Pan Ziqiang,Shen Wenquan(Science and Technology Commission,china national Nuclear corporation,beijing1000822,china)

By analyzing the challenges of china's energy supply,an excellent perspective of nuclear power development in china has been *** into account the mid-long term development requirements,a comprehensive,coordinated and sustainable nuclear power strategic consideration and proposal is put *** our national nuclear industry can not only catch up with the world advanced level in proper time,but also possess the enough stamina of sustainability.

关键词： nuclear energy strategic role sustainability

Experimental study of the relationship between fluid density and saturation and sonic wave velocity of rock samples from the WXS Depression,South china Sea

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Petroleum Science 2011年第1期8卷 43-48页

作者： Pei Fagen Zou Changchun He Tao Pan Lingzhi Xiao Kun Shi Ge Ren Keying Key Laboratory of Geo-detection（china University of Geosciences Beijing）Ministry of EducationBeijing 100083 China School of Earth and Space Sciences Peking UniversityBeijing 100871China Zhanjiang Branch of china national Offshore Oil corporation Ltd. Guangdong 524057China

The relationship between fluid density and saturation and sonic wave velocity of rock samples taken from the WXS Depression in the South china Sea was studied by an oil-water replacement experiment under simulated in-situ temperature and pressure *** kinds of low-density oils（0.691 and 0.749 g/cm^3） and two kinds of high-density oils（0.834 and 0.873 g/cm^3） were used to saturate the rock samples at different oil-saturation states,and the saturated P- and S-wave velocities were *** Gassmann＇s equation,the theoretical P- and S-wave velocities were also calculated by the fluid replacement *** the comparison of the measured values and the theoretical values, this study comes to the following conclusions.（1） With the increase of oil saturation and the decrease of water saturation,the P-wave velocity of rock samples saturated by low-density oil increases and the changing rule is in accord with the effective fluid theory;the P-wave velocity of rock samples saturated by high-density oil decreases and the changing rule goes against the theory.（2） With the increase of oil density（namely 0.691→0.749→0.834→0.873 g/cm^3） when oil saturation is unchanged,P-wave velocity increases gradually.（3） The S-wave velocity is always stable and is not affected by the change of oil density and *** results can be used to constrain pre-stack seismic inversion,and the variation rule of sonic wave velocity is valuable for hydrocarbon identification in the study area.

关键词： Rock physics saturation compressional wave shear wave water drive Gassmann's equation fluid replacement

Spatio-temporal carbon isotope variation during the Ediacaran period in South china and its impact on bio-evolution

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Science china Earth Sciences 2009年第10期52卷 1520-1528页

作者： WANG XinQiang1 & SHI XiaoYing1,2 1 School of Earth Science and Mineral Resources, china University of Geosciences, beijing 100083, china 2 State Key Laboratory of Geological Processes and Mineral Resources, beijing 100083, china School of Earth Science and Mineral Resources China University of Geosciences Beijing China State Key Laboratory of Geological Processes and Mineral Resources Beijing China

The Ediacaran period is characterized by the extremely negative carbon isotope anomalies and great biotic evolution in Earth history. At least four negative carbon isotope anomalies have been reported from this interval in South china so far. It is traditionally argued that the isotope variations can be used as a useful tool for global correlation of Ediacaran succession; however, more and more researches argued against this idea. We reviewed the previously published carbon isotope data in South china, and distributed the mean values of a certain time to the paleogeographic maps. The results show that the carbon isotope values (δ13C) vary greatly in different environments, but a clear tendency of becoming lighter from shallow platform to deep basin, with a maximum variation up to 1‰ Moreover, the important changes in Ediacaran biota, marked by the introducing of new taxa or ecologic groups, seemed to always postdate the negative anomalies but coincide with the positive shift. If the negative excursions represented the oxidation of a large dissolved organic carbon (DOC) reservoir in the ocean, the diverse Ediacaran organisms and the carbon isotope anomalies may suggest totally different environments: oxic and anoxic/euxinic. We also suggest that the elimination of euxinic state through precipitation of pyrites is one of the important environment factors in prompting the Ediacaran bio-evolution.

关键词： Ediacaran South china carbon isotope spatio-temporal variations bio-evolution

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推进创新型企业建设引领行业科技进步

中国煤炭 2010年第3期36卷 9-12页

作者： china national Coal Group corporation (Technical Development Division,china national Coal Group corporation,Chaoyang district,beijing 100120,china) 中煤能源集团科技发展部

中煤能源集团围绕实现中煤集团"22255"战略目标,大力推进科技自主创新能力建设,组织实施由集团煤层气公司牵头发起创建的"煤层气产业技术创新战略联盟"等若干重大科技专项和行业重大关键技术攻关。介绍了其科研开发体系和自主开发的重... 详细信息

中煤能源集团围绕实现中煤集团"22255"战略目标,大力推进科技自主创新能力建设,组织实施由集团煤层气公司牵头发起创建的"煤层气产业技术创新战略联盟"等若干重大科技专项和行业重大关键技术攻关。介绍了其科研开发体系和自主开发的重大科技项目。

关键词：煤炭企业企业发展自主创新科技发展中煤能源集团

Analysis on the Dynamical Process of Donghekou Rockslide-Debris Flow Triggered by 5.12 Wenchuan Earthquake

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Journal of Mountain Science 2011年第2期8卷 140-148页

作者： SUN Ping ZHANG Yongshuang SHI Jusong CHEN Liwei Key Laboratory of Neotectonic Movement & Geohazard Ministry of Land and Resources Beijing China Institute of Geomechanics Chinese Academy of Geological Sciences Beijing China china Nuclear Power Engineering corporation Ltd. Beijing China

Among the geo-hazards caused by the great Wenchuan Earthquake, the rapid and long runout rockslide-debris flow is of primary concern due to the large volume of displaced material and the resultant catastrophic impacts to the landscape and socioeconomic structure. In order to analyze the dynamical process of this kind of geo-hazard, the Donghekou rockslide-debris flow is given as an example in this paper. This event, which killed 780 people, initiated at an elevation of 1300 m with a total long run-out distance of more than 2400 m. The slide mass is mainly composed of dolomite limestone and siliceous limestone of Sinian system, together with carbon slate and phyllite of Cambrian. During the processes from slide initiation to the final cessation of slide movement, five dynamic stages took place, here identified as the initiation stage, the acceleration of movement stage, the air-blast effect stage, the impact and redirection stage and the long runout slidematerial accumulation stage. Field investigations indicate that due to the effects of the earthquake, the dynamics of the Donghekou rockslide-debris flow are apparently controlled by geologic and tectonic conditions, the local geomorphological aspects of the terrain, and the microstructural and macroscopic mechanical properties of rocks which compose the slide mass. These three main factors which dictate the Donghekou rockslide-debris flow dynamics are discussed in detail in this paper, and significant results of field investigations and tests of materials are presented. The above dynamical processes are analyzed in this paper, and some useful conclusions have been gained.

关键词： Dynamical process Donghekou Rockslide-debris flow Wenchuan earthquake

Ambient noise near the sea-route

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Science china(Physics,Mechanics & Astronomy) 2009年第1期52卷 40-45页

作者： HE Li1,2, LI ZhengLin1,3 & PENG ZhaoHui1 1 national Laboratory of Acoustics, Institute of Acoustics, Chinese Academy of Sciences, beijing 100190, china 2 Institute of Geology and Geophysics, Chinese Academy of Sciences, beijing 100029, china 3 NanHai Laboratory of Acoustics, Institute of Acoustics, Chinese Academy of Sciences, Haikou 570206, china national Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences Beijing China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China NanHai Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences Haikou China

Ambient noise data measured in an experiment conducted in shallow water near a sea-route were analyzed. It was observed that, at low frequency, the horizontal correlation has an obvious difference from that predicted by the classical ambient noise model. The theoretical analyses show that this phenomenon is caused by wind noise together with the discrete shipping noise nearby. An ambient noise model was proposed to include the effects caused by both the noise sources. Data measured at different times verify that the proposed model can be used to forecast the ambient noise field in shallow water near the sea-route.

关键词： ambient noise model horizontal correlation discrete ships

Flow imaging method of electromagnetic measurement in well logging

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Science china Earth Sciences 2008年第S2期51卷 181-185页

作者： WU XiLing,WANG XiaoXing,ZHAO YanWei & YANG Mei School of Resource and Information Technology,china University of Petroleum,beijing 102249,china School of Resource and Information Technology China University of Petroleum Beijing China

Multiphase flow in an oil well is a dynamic phenomenon of inhomogeneous medium,which should be studied in a nonlinear way. This paper presents an electromagnetic measurement method based on the electrical property differences between oil,gas and water to scan,inverse and show the distribution and condition of multiphase flow. Both numerical simulation and physical experiments have proved that clear images could be obtained by this way.

关键词： well multiphase flow electromagnetic wave flow imaging

PETROLEUM SYSTEM IN china -1963 In Retrospect and a New Case OF Application

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china Oil & Gas 1998年第4期5卷 229-231页

作者： Hu Chaoyuan(china national Petroleum corporation)Liao Xi(University of petroleum, beijing)