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SYNTHESIS AND CHARACTERIZATION OF PHTHALAZINONE POLY(ARYL ETHER SULFONE KETONE)WITH CARBONYL GROUP

Chinese Journal of Polymer Science 2002年第3期20卷 225-229页

作者： Ying-nan Xuan Yan Gao Yong Huang Xi-gao Jian Laboratory of Cellulose and Lignocellulosics Chemistry Guangzhou Institute of Chemistry Chinese Academy of Sciences, Guangzhou 510650 china Institute of Chemistry Chinese Academy of Sciences, beijing 100080 china Department of Polymer Science, College of Chemical Engineering Dalian University of Technology, Dalian 116012, china Chinese Acad Sci Guangzhou Inst Chem Lab Cellulose & Lignocellulos Chem Guangzhou 510650 Peoples R China Chinese Acad Sci Inst Chem Beijing 100080 Peoples R China Dalian Univ Technol Coll Chem Engn Dept Polymer Sci Dalian 116012 Peoples R China

A kind of novel heat-resistant, high performance engineering thermoplastic phthalazinone poly(aryl ether sulfone ketone) (PPESK) containing a carboxyl group in its side chain was prepared by the nucleophilic displacement reaction of 4-(4-hydroxylphenyl)- 1 (2H)-phthalazinone with di(4-chlorophenyl) sulfone, 4,4'-difluoro-benzophenone and phenolphthalin in sulfolane in the presence of K2CO3.to produce high molecular weight polymers which can be dissolved in some polar solvents such as chloroform and nitrobenzene at room temperature and can be easily cast into flexible, yellowish and transparent films. PPESK is an amorphous polymer having a decomposition temperature above 400degreesC, which indicates that it has high thermal stability. At the same time, the thermal properties of PPESKs with dicyandiamide (DICY) as curing agent indicated that the heat-resistance properties of the PPESKs are improved after curing. The apparent activation energy (A-E) of the cross-linking reaction and the reaction order (n) of PPESK/DICY were found to be 52.2 kJ/mol and ca. 1.0, respectively. Therefore, the cross-linking reaction is approximately a first order reaction.

关键词： poly(aryl ether sulfone ketone) synthesis active pendant group

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An Interferometric Method for Atomic Interferometer Gyroscope

An Interferometric Method for Atomic Interferometer Gyroscop...

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2010 International Symposium on Inertial Technology and Navigation

作者： QI Lu FANG Jian-cheng (national Key Laboratory of Science and Technology on Inertia Beihang University beijing 100191 china)

＜正＞In this passage,we provide analytical descriptions of the two popular implementations of atomic interferometer gyroscopes,atomic state gyroscopes and matter wave *** fundamental physical mechanisms of the two implementations are analyzed and modelled;and typical examples of both are *** we compare and contrast both implementations in the practical perspective,and bring out a modified interferometric method,which is better suited for practical application.

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Copulatory pattern and behavior in a semi-captive population of Eld's deer

Copulatory pattern and behavior in a semi-captive population...

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第七届全国野生动物生态与资源保护学术研讨会

作者： Zhi-Gao ZENG Yan-Ling SONG and Qiong ZHANG (Key Laboratory of Animal Ecology and Conservation Biology,Institute of Zoology,Chinese Academy of Sciences,beijing 100101,china)

Male copulatory patterns,female multiple copulation and male post-copulatory guarding were studied in Eld’s deer Cervus eldi in Datian national Nature Reserve,*** behavior in 18 females and 11 males from a group of 61 semi-captive Eld’s deer were *** majority(55.8%) of copulations occurred between 15:00-19:00 *** ejaculatory mount was preceded by an average of 5.1 prior *** copulation consisted of a single thrust with ejaculation during one intromission,with no *** copulatory pattern is classified as pattern No.15(no lock,no intravaginal thrusting,single intromission,and multiple ejaculation)and No.16(no lock,no intravaginal thrusting,single intromission,and single ejaculation)under Dewsbury’s scheme(1972)and as No.16 (no lock,no thrusting,single and brief intromission)under Dixson’s classification(1998).Copulation frequency was 1.5±0.9 times for males/ females with the same female/male per *** duration of the final mount,which included ejaculation,was brief(3.4±1.3.s),and ejaculation usually terminated *** females copulated more than once in this study:three of them copulated with several males(multi-male copulations)and the remainder copulated with a single male(repeated copulations). Our results indicate that some female Eld’s deer may seek multiple copulations to be a strategy to improve the genetic quality of their offspring or to avoid ***-copulatory guarding of females by males followed all copulations,with dominant males guarding for significantly longer than subordinate *** males appear to be more effective at post-copulatory guarding than subordinate *** males engaged in a quicker pre-copulatory phase to improve their chances of finishing copulation before being forced to accede to dominant males.

关键词： Cervus eldi copulatory pattern female multiple copulation post-copulatory guarding dominant male subordinate male

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Searching for Variable Stars in the Field of NGC 7789

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Chinese Journal of Astronomy and Astrophysics 2003年第2期3卷 151-165页

作者： Xiao-Bin Zhang, Li-Cai Deng, Yu Xin and Xu Zhounational Astronomical Observatories, Chinese Academy of Sciences, beijing 100012 CAS-PKU Joint beijing Astrophysics Center, beijing 100871 national Astronomical Observatories CAS NAOC Beijing 100012 China []CAS-PKU Joint Beijing Astrophysics Center Beijing 100871

We present the results of a time-series CCD photometric survey of variable stars in the field of the open cluster NGC 7789. In a field of about one degree centering on the cluster, a total of 28 new variable stars are discovered (14 W UMa systems, nine EA-type eclipsing binaries, one RR Lyr star, and four unclassified). In addition, we recovered 11 old variables previously discovered by other authors. Preliminary parameters are given for some of these variables.

关键词： open clusters: individual (NGC 7789) - stars: variables (general) - binaries: general

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基于学科交叉与目标一致性的重大研究计划资助绩效评价

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科研管理 2017年第4期38卷 132-144页

作者：汪雪锋陈云王志楠黄颖马晶任惠超逄金辉北京理工大学管理与经济学院北京100081 中国船舶重工集团公司第714研究所北京100101 北京理工大学图书馆北京100081

国家自然科学基金委重大研究计划拟通过整合与集成不同学科背景、不同学术思路和不同层次的项目群,促进学科交叉融合,提高各研究领域协同合作能力,推进重大难点科学问题的解决。本文利用Web of Science平台中的论文数据,从学科交叉、研... 详细信息

国家自然科学基金委重大研究计划拟通过整合与集成不同学科背景、不同学术思路和不同层次的项目群,促进学科交叉融合,提高各研究领域协同合作能力,推进重大难点科学问题的解决。本文利用Web of Science平台中的论文数据,从学科交叉、研究内容与资助目标一致性两个维度对重大研究计划资助绩效进行了评价研究。研究结果表明;(1)重大研究计划的实施有效推动了学科的交叉融合,提高了协同合作能力,但不同计划间的学科交叉情况存在较大差异,数理科学部牵头实施计划的学科集成程度相对较高,管理科学部则涉及的学科范围最广;(2)不同计划资助论文的研究内容与资助目标的一致性存在较大差异,研究主题与研究目标相关性较强,但聚焦程度相对较差。总体上,重大研究计划的学科交叉程度还有较大提升空间,在研究内容与资助目标一致性方面还有待提高。

关键词：绩效评价重大研究计划目标定位学科交叉一致性评价

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Perturbation Methods of Stability Analysis for Parallel Real-Time Digital Simulation Models

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Journal of Systems Engineering and Electronics 1992年第2期3卷 38-48页

作者： Fei Jinggaobeijing Institute of Computer Application and Simulation Technology, P.O. Box 142-213. beijing 100854, china beijing Institute of Computer Application and Simulation Technology P.O. Box 142-213. Beijing 100854. China

In this paper, the stability analysis for parallel real-time digital simulation models is discussed. The coupling coefficient perturbation method and the simulation stepsize perturbation method are established. For two classes of systems of test equations, we construct the parallel simulation models and prove that they have the stability behaviour which is similar to the original continuous systems.

关键词： Digital simulation Parallel algorithms Ordinary differential equations Stability Model.

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Earthquake Recurrences Since Late Pleistocene in Nankai Trough of Kumano

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地学前缘 2009年第S1期16卷 221-221页

作者： Tao Jiang~1,Shenghua Li~2,Chunfeng Li~3.Xinong Xie~1,Xin Su~4,Jianye Ren~1 1.Key Laboratory of Tectonics and Petroleum Resources,china University of Geosciences(Wuhan),Wuhan 43.074,china. 2.Department of Earth Sciences,University of Hong Kong,Pokfullam Road,Hong Kong,china 3.School of Ocean and Earth Sciences,Tongji University,Shanghai 200092,china 4.School of Marine Geosciences,china University of Geosciences(beijing),beijing 100083.china

The Nankai Trough has a 13.0-year record of generating large earthquakes(M_w>8)with a recurrence time of～100-200 a,but unfortunately,we don’t know the frequency of earthquakes *** from recent expeditions of NanTroSEIZE Stage 1 IODP 3.4/3.5/3.6 recovered many cycles of turbidites since late Pleistocene,which are triggered during the past earthquake *** purpose is

关键词： earthquake SEIZE IODP turbidite OSL

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国外教育政策执行研究“三大主题”述评及其启示

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外国教育研究 2011年第8期38卷 81-86页

作者：蒋园园国家教育行政学院国际教育教研部北京102617

20世纪70年代以来,国外教育政策分析和研究人员把教育政策执行作为研究和改进的对象,从分析模型、执行模式和相关变量的视角,对教育政策执行的理论模式进行比较分析,并指出了不同模型的侧重点。纵观相关研究内容发现这些研究主要关注三... 详细信息

20世纪70年代以来,国外教育政策分析和研究人员把教育政策执行作为研究和改进的对象,从分析模型、执行模式和相关变量的视角,对教育政策执行的理论模式进行比较分析,并指出了不同模型的侧重点。纵观相关研究内容发现这些研究主要关注三方面主题,其侧重点虽各不相同,但每一研究主题都有恰当的目标设置、严格的研究设计,从各种不同角度提出了有价值的分析思路,这对我国的教育政策执行研究有着重要的启示和借鉴意义。

关键词：教育政策执行研究国外主题

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Fischer Plots of Wumishan Cyclothems,Precambrian Records of Third-OrderSea-Level Changes

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Journal of china University of Geosciences 2001年第1期12卷 1-10页

作者： Mei Mingxiang Faculty of Earth Sciences and Mineral Resources, china University of Geosciences, beijing 100083.Ma Yongsheng china Petrochemical Corporation (SINOPEC), beijing 100029 Zhou Hongrui Du Benming Luo Zhiqing Guo Qingyin Faculty of Earth Sc Faculty of Earth Sciences and Mineral Resources China University of Geosciences china Petrochemical Corporation SINOPEC

The Mesoproterozoic Wumishan Formation ((13.0 ± 20 ) Ma - (l 207 ± 10) Ma) in Jixian, Tianjin represents a succession of 3.3.0 meter thick carbonate strata where are the best developed stromatolite biostromes and thrombolite bioherms. These biostromes and bioherms, together with tidal-flat dolomites and muddy dolostones, form Wumishan cyclothems with approximately symmetrical faciessuccession fabrics, which belong to carbonate meter-scale cyclic sequences of peritidal type. These cyclothems are overlain by lagoon dolomitic mudstones and shales and by frequently developed paleosol layers, indicating that the boundary of Wumishan cyclothems is marked by an instantaneously-exposed punctuated surface. Viewed form the regularly vertical stacking patterns of Wumishan cyclothems in long-term sequences, 26 third-order sequences may be discerned in Wumishan Formation. These thirdorder sequences may also be incorporated into six second-order sequences. In order to study the variation range of third-order sea-level changes and the formation period of third-order sequence, 626 cyclothems are discerned in the middle and upper parts of Wumishan Formation where the outcrops are well developed. In terms of the total thickness and the formation period of Mesoproterozoic Wumishan Formation, the crust subsidence rate in the sedimentary period of Wumishan Formation is supposed to be 3.meters at each interval of 100 thousands years. Based on this assumption, Fischer plot might be designed to simulate the third-order sea-level changing pattern.

关键词： Wumisban cyclothems Fischer plots Mesoproterozoic Jixian of Tianjin.

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Effect of cooling rate after solution on microstructure and creep properties of single crystal superalloy DD3

Effect of cooling rate after solution on microstructure and ...

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第十一届国际材联亚洲材料大会

作者： LIU Weiwei and TANG Dingzhong national Key Laboratory of Science and Technology on Advanced High Temperature Structural Materials beijing Institute of Aeronautical Materials beijing 100094 {3.

＜正＞The effect of different cooling rate on microstructure and creep properties of DD3.single crystal superalloy after solution treatment was investigated. 10°C/min cooling rate is adverse to the creep properties performed at all the conditions of 760℃/786 MPa,982℃/210 MPa and 103.℃/161 *** best creep lives can be obtained with 149℃/min cooling rate specimens at 760℃/786 *** 982℃/210 MPa and 103.℃/161 MPa,a cooling rate of 3.℃/min shows the best creep properties in the four kinds of *** experimental results show that the size ofγ’ precipitates decreases with the increasing of cooling rate from 10℃/min to 149℃/*** the creep test,the directional coarsening ofγ’ precipitates occurred andγ’ rafting is formed.

关键词： DD3 single crystal superalloy cooling rate microstructure creep property

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