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Synthesis and Structure of A Novel Caged Bicyclic Phosphate Flame Retardant 被引量:28
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作者 Li, X Ou, YX +1 位作者 Zhang, YH Lian, DJ 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第10期887-890,共4页
PI novel caged bicyclic phosphate flame retardant tri(1-oxo-2,6,7-trioxa-1-phosphabicyclo [2.2.2] octane-methyl) phosphate (Trimer) was synthesized from 1-oxo-4-hydroxymethyl-2,6,7-trioxa-1-phosphabicyclo [2.2.2] octa... PI novel caged bicyclic phosphate flame retardant tri(1-oxo-2,6,7-trioxa-1-phosphabicyclo [2.2.2] octane-methyl) phosphate (Trimer) was synthesized from 1-oxo-4-hydroxymethyl-2,6,7-trioxa-1-phosphabicyclo [2.2.2] octane (PEPA) and phosphorus oxychloride in this paper. Its structure was characterized by elemental analysis. FTIR, H-1 NMR. P-31 NMR and X-ray diffraction analysis. 展开更多
关键词 caged bicyclic phosphate flame retardant crystal structure
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THREE-DIMENSIONAL ELLIPTIC CRACK UNDER IMPACT LOADING 被引量:4
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作者 Sun Zhufeng Wu Xiangfa Fan Tianyou 《Acta Mechanica Solida Sinica》 SCIE EI 2001年第4期312-316,共5页
The dynamic stress intensity factor of a three-dimensionalelliptic crack under impact loading is determined with the finiteelement method. The computation results can take into account theinfluence of time and the rat... The dynamic stress intensity factor of a three-dimensionalelliptic crack under impact loading is determined with the finiteelement method. The computation results can take into account theinfluence of time and the ratio of the wave speeds on the stressintensity factor. The present method is suitable not only forthree-dimensional dynamic crack, but also for three-dimensionaldynamic contact. 展开更多
关键词 dynamic loading three-dimensional elliptic crack finite element dynamicstress intensity factor
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Chinese Fuzzy Ontology Mapping Based on Support Vector Machine 被引量:2
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作者 Liu Jie Ma Yun +1 位作者 Tang Shiping Lu Peng 《China Communications》 SCIE CSCD 2012年第3期134-144,共11页
Taking into account that fuzzy ontology mapping has wide application and cannot be dealt with in many fields at present,a Chinese fuzzy ontology model and a method for Chinese fuzzy ontology mapping are proposed.The m... Taking into account that fuzzy ontology mapping has wide application and cannot be dealt with in many fields at present,a Chinese fuzzy ontology model and a method for Chinese fuzzy ontology mapping are proposed.The mapping discovery between two ontologies is achieved by computing the similarity between the concepts of two ontologies.Every concept consists of four features of concept name,property,instance and structure.First,the algorithms of calculating four individual similarities corresponding to the four features are given.Secondly,the similarity vectors consisting of four weighted individual similarities are built,and the weights are the linear function of harmony and reliability.The similarity vector is used to represent the similarity relation between two concepts which belong to different fuzzy ontolgoies.Lastly,Support Vector Machine(SVM) is used to get the mapping concept pairs by the similarity vectors.Experiment results are satisfactory. 展开更多
关键词 支持向量机 本体映射 中国人 模糊 相似性 映射方法 线性函数 肾脏病
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CONSERVATION LAWS AND SYMMETRIES OF SYSTEMS WITH UNILATERAL CONSTRAINTS IN PHASE SPACE 被引量:2
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作者 Zhang Yi Mei Fengxiang 《Acta Mechanica Solida Sinica》 SCIE EI 1999年第1期22-30,共9页
By introducing the generalized quasi-symmetry of the infinitesimaltransformation for transformation group G_r, this paper studies theconservation laws and symmetries of dynamical systems with unilateralconstraints in ... By introducing the generalized quasi-symmetry of the infinitesimaltransformation for transformation group G_r, this paper studies theconservation laws and symmetries of dynamical systems with unilateralconstraints in phase space. Noether's theorem and Noether's inversetheorem for me- chanical system with unilateral constraints in phasespace are obtained and two kinds of equivalent forms of generalizedKilling equations which are used to determine the generators of theinfinitesimal group transformation are given. 展开更多
关键词 analytical mechanics conservation law SYMMETRY
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STUDY ON THE INTERACTION BETWEEN POLYVINYLPYRROLIDONE AND PLATINUM METALS DURING THE FORMATION OF THE COLLOIDAL METAL NANOPARTICLES 被引量:1
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作者 Tu, Wei-xia Zuo, Xiao-bin Liu, Han-fan 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2008年第1期23-29,共7页
Several PVP-stabilized colloidal platinum metals nanoparticles have been synthesized and characterized by FTIR and TEM.Comparing with the pure PVP,carbonyl groups of PVP in the mixture of PVP and the metal precursors ... Several PVP-stabilized colloidal platinum metals nanoparticles have been synthesized and characterized by FTIR and TEM.Comparing with the pure PVP,carbonyl groups of PVP in the mixture of PVP and the metal precursors or in the PVP-stabilized metal nanoparticles have obvious peak shifts in FTIR spectra.The peak shifts reveal the interaction between PVP and the metal species.The interaction between PVP and metal precursors has effect on the formation of the colloidal metal nanoparticles.Strength of the intera... 展开更多
关键词 Colloidal metal nanoparticles Metal precursor PVP Interaction
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Synthesis of 2H-3,1-pyrazolo[3,4-e]oxazines via a new conversion of Friedlander reaction
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作者 Li, Jia Rong Zhang, Li Jun +4 位作者 Chen, Jin Nan Yang, Xi Quan Wang, Li Jun Zhao, Xiao Fan Qiu, Jun Xia 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第6期636-638,共3页
2H-3,l-Pyrazolo[3,4-e]oxazines (5a-c) and tacrine analogies (6a-c) were designed and prepared using 5-amino-4-cyanopyrazole (7) and cycloketones (2a-c) as reactants. The study demonstrated that the new conversion exis... 2H-3,l-Pyrazolo[3,4-e]oxazines (5a-c) and tacrine analogies (6a-c) were designed and prepared using 5-amino-4-cyanopyrazole (7) and cycloketones (2a-c) as reactants. The study demonstrated that the new conversion existed in the Friedlander reaction of o-aminocyanopyrazole with cycloketones. (C) 2007 Jia Rong Li. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved. 展开更多
关键词 PYRAZOLE OXAZINES TACRINE CYCLOCONDENSATION SYNTHESIS
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NOVEL OXIDATION OF HEXABENZYLHEXAAZA-ISOWURTZITANE BY Me2CHNO2/CuCl/Py/O2
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作者 Guan, XP Yan, H +1 位作者 Sun, JG Yu, YZ 《Chinese Chemical Letters》 SCIE CAS CSCD 1996年第6期511-512,共2页
Treatheent of2.4. 6. 8, 10.12-hexahany1-2.4. 6, 8,10, 12-hexaazateteracyclo [5.5.0.03.9 03.11]dodecane (1) with Me.CHNO2/CuCl/Py/O2 results in C(1)-C(7) okidative cleavop to give 1,3.4,5,7,8-hexabenzy-2,6-dioxo-cis-c... Treatheent of2.4. 6. 8, 10.12-hexahany1-2.4. 6, 8,10, 12-hexaazateteracyclo [5.5.0.03.9 03.11]dodecane (1) with Me.CHNO2/CuCl/Py/O2 results in C(1)-C(7) okidative cleavop to give 1,3.4,5,7,8-hexabenzy-2,6-dioxo-cis-cisid-cis-decahydro-1H.5H-diimidazo [4,5-b:4'.5’-elpyrazine(2) 展开更多
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Synergistic Effect in Special Selectivity Mixed Gas Chromatographic Stationary Phase in the Separation of Aromatic Compounds
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作者 Yuan, LM Fu, RN +2 位作者 Gui, SH Chen, XX Dai, RJ 《Chinese Chemical Letters》 SCIE CAS CSCD 1998年第2期151-155,共5页
The gas chromatographic separations of aromatic compounds using special mixed stationary phases consisting of pp-beta-CD+AgNO3, pp-beta-CD+TINO3, pp-beta-CD+di-n-butly phthalate, pp-beta-CD+BPBHpB liquid crystalline, ... The gas chromatographic separations of aromatic compounds using special mixed stationary phases consisting of pp-beta-CD+AgNO3, pp-beta-CD+TINO3, pp-beta-CD+di-n-butly phthalate, pp-beta-CD+BPBHpB liquid crystalline, and bentone-34+AgNO3 were investigated. Besides pp-beta-CD+di-n-butyl phthalate, most of the separations deviated from the additivity and a synergistic effect was observed. The separation effects depend on the temperature and how mixing is accomplished. 展开更多
关键词 gas chromatography mixed stationary phase synergistic effect aromatic compounds
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放电等离子烧结温度对钨合金的组织及动态力学性能的影响 被引量:8
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作者 王迎春 李树奎 +1 位作者 王富耻 罗鸿志 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2010年第10期1807-1810,共4页
以纳米93W-4.9Ni-2.1Fe合金粉末为原料,研究放电等离子烧结温度对钨合金组织和动态力学性能的影响。结果表明,采用放电等离子烧结方法可制备出组织均匀的细晶钨合金。当烧结温度在950~1400℃时,随着烧结温度的增加,钨颗粒平均尺寸由2μ... 以纳米93W-4.9Ni-2.1Fe合金粉末为原料,研究放电等离子烧结温度对钨合金组织和动态力学性能的影响。结果表明,采用放电等离子烧结方法可制备出组织均匀的细晶钨合金。当烧结温度在950~1400℃时,随着烧结温度的增加,钨颗粒平均尺寸由2μm增大到10μm,试样动态抗压强度随之降低;动态压缩过程中,烧结温度在1000~1200℃的试样塑性均较好,而当烧结温度超过1300℃时,试样的塑性很低,表现为明显的脆性状态。 展开更多
关键词 放电等离子 烧结温度 细晶钨合金 合金组织 动态力学性能 Dynamic Mechanical Properties Microstructure SINTERING Temperature 试样 颗粒平均尺寸 压缩过程 塑性 烧结方法 抗压强度 合金粉末 制备 原料 性状 纳米 结果
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TC4合金绝热剪切动态演变过程数值模拟研究 被引量:5
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作者 李建崇 李树奎 范群波 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2010年第12期2193-2195,共3页
对TC4合金强迫剪切过程进行了数值模拟,获得了绝热剪切过程中变形局域化区域内的von-Mises应力、有效塑性应变以及温度的分布规律。通过分析发现:大量应变集中于帽形试样变形局域化区域内,且在试样两拐角处最大;变形局域化区域内温度明... 对TC4合金强迫剪切过程进行了数值模拟,获得了绝热剪切过程中变形局域化区域内的von-Mises应力、有效塑性应变以及温度的分布规律。通过分析发现:大量应变集中于帽形试样变形局域化区域内,且在试样两拐角处最大;变形局域化区域内温度明显高于基体温度,且在试样两拐角处最高。结果表明,绝热剪切带内温度达到了TC4合金的再结晶温度,这为TC4合金绝热剪切带内微观组织变形机制的研究提供了依据。 展开更多
关键词 TC4合金 绝热剪切带 动态 演变过程 数值模拟研究 Dynamic LOADING during 变形局域化 再结晶温度 剪切过程 有效塑性应变 帽形试样 区域 应变集中 微观组织 基体温度 分布规律 变形机制 应力 结果
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Preface 被引量:13
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作者 Chen, Zhen-Qing Li, Wenbo Li, Zenghu 《Science China Mathematics》 SCIE 2012年第11期2193-2193,共1页
Founded in 1935, the Institute of Mathematical Statistics (IMS) is an international professional and scholastic society devoted to the development, dissemination, and application of statistics and probability.IMS Chin... Founded in 1935, the Institute of Mathematical Statistics (IMS) is an international professional and scholastic society devoted to the development, dissemination, and application of statistics and probability.IMS China, established in 2007, promotes the participation of Chinese scholars in activities of the Institute of Mathematical Statistics. 展开更多
关键词 数理统计 中国学者 学术团体 IMS 国际性 概率
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Failure wave motion of 3D-C/SiC composites subjected to shock compression 被引量:2
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作者 Qingming Zhang Fenglei Huang Liming Han 《Chinese Science Bulletin》 SCIE EI CAS 2000年第5期408-411,共4页
The response and failure behavior of 3D-C/S軨 composites subjected to shock compression have been experimentally studied. With the help of a one-stage light gas gun, the 3D-C/SiC composite samples, which are subjected... The response and failure behavior of 3D-C/S軨 composites subjected to shock compression have been experimentally studied. With the help of a one-stage light gas gun, the 3D-C/SiC composite samples, which are subjected to the plane shock compression by LY-12 aluminum flyer sheets with different speeds become available. Based on the analysis of observation for the curve of pressure vs time, which has been measured from the tests as well as from the samples, it is found that when the shock speed is larger than a critical value, the material of 3D-C/SIC will be comminuted and the failure surface will move from the shock plane to its inward direction in the waveform. 展开更多
关键词 FAILURE wave comminution 3D-fabric REINFORCED COMPOSITE CERAMIC matrix composite.
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First integral and integral invariant of Birkhoffian system 被引量:2
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作者 Fengxiang Mei Huibin Wu 《Chinese Science Bulletin》 SCIE EI CAS 2000年第5期412-414,共3页
The variational equation of the Birkhoffian system is established, by which it is proved that an integral invariant can be constructed with a known first integral. And its inverse is also correct.
关键词 ANALYTICAL MECHANICS BirkhofGan SYSTEM FIRST INTEGRAL INTEGRAL invariant.
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The existence and stability of traveling waves with transition layers for the S-K-T competition model with cross-diffusion 被引量:3
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作者 Wu YaPing Zhao Ye 《Science China Mathematics》 SCIE 2010年第5期124-147,共24页
This paper is concerned with the existence and stability of traveling waves with transition layers for a quasi-linear competition system with cross diffusion,which was first proposed by Shegesada,Kawasaki and Teramoto... This paper is concerned with the existence and stability of traveling waves with transition layers for a quasi-linear competition system with cross diffusion,which was first proposed by Shegesada,Kawasaki and Teramoto.When one of the random diffusion rates is small and the cross-diffusion rate is not small,by the geometric singular perturbation method,the existence of traveling waves with transition layers is obtained.Further,by the detailed spectral analysis and topological index method,the traveling waves with transition layers are proved to be locally exponentially stable with shift. 展开更多
关键词 TRAVELING waves EXISTENCE STABILITY CROSS-DIFFUSION spectral analysis UNSTABLE BUNDLE
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Boosting performance in attack intention recognition by integrating multiple techniques 被引量:2
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作者 Hao Bai (1) david_xiaobai@126.com Kunsheng Wang (2) Changzhen Hu (1) Gang Zhang (2) Xiaochuan Jing (2) 《Frontiers of Computer Science》 SCIE EI CSCD 2011年第1期109-118,共10页
Recognizing attack intention is crucial for security analysis. In recent years, a number of methods for attack intention recognition have been proposed. However, most of these techniques mainly focus on the alerts of ... Recognizing attack intention is crucial for security analysis. In recent years, a number of methods for attack intention recognition have been proposed. However, most of these techniques mainly focus on the alerts of an intrusion detection system and use algorithms of low efficiency that mine frequent attack patterns without reconstructing attack paths. In this paper, a novel and effective method is proposed, which integrates several techniques to identify attack intentions. Using this method, a Bayesian-based attack scenario is constructed, where frequent attack patterns are identified using an efficient data-mining algorithm based on frequent patterns. Subsequently, attack paths are rebuilt by recorrelating frequent attack patterns mined in the scenario. The experimental results demonstrate the capability of our method in rebuilding attack paths, recognizing attack intentions as well as in saving system resources. Specifically, to the best of our knowledge, the proposed method is the first to correlate complementary intrusion evidence with frequent pattern mining techniques based on the FP-Growth algorithm to rebuild attack paths and to recognize attack intentions. 展开更多
关键词 attack path attack intention compensatoryintrusion evidence FP-GROWTH
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挤压态钨合金绝热剪切局域化及微裂纹萌生现象研究(英文) 被引量:1
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作者 彭磊 李树奎 +1 位作者 周晓青 才鸿年 《稀有金属材料与工程》 SCIE EI CAS CSCD 北大核心 2010年第12期2084-2087,共4页
研究变形量对挤压态钨合金动态力学行为的影响及钨合金绝热剪切带内的微观开裂行为。结果表明,加载方向垂直于纤维取向时,随变形量由0增加至40.8%,挤压态钨合金绝热剪切敏感性显著增大;由对钨合金绝热剪切带内微观组织的SEM观察可知,靠... 研究变形量对挤压态钨合金动态力学行为的影响及钨合金绝热剪切带内的微观开裂行为。结果表明,加载方向垂直于纤维取向时,随变形量由0增加至40.8%,挤压态钨合金绝热剪切敏感性显著增大;由对钨合金绝热剪切带内微观组织的SEM观察可知,靠近绝热剪切带中心处出现在微裂纹且微裂纹萌生于W-M界面及W颗粒内部;进一步的TEM观察可知,剪切带内W-M界面处存在大量的位错塞积,W颗粒中则出现亚晶内部及沿亚晶界扩展的微裂纹。 展开更多
关键词 挤压态 钨合金 绝热剪切带 局域化 微裂纹萌生 现象研究 TUNGSTEN HEAVY Alloy dynamic mechanical behavior uniaxial compression TUNGSTEN HEAVY alloy SHEAR band electron microscopy interface adiabatic SHEAR 绝热剪切敏感性 动态力学行为 变形量 influence direction 纤维取向
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On the electron-beam (EB) irradiation and grafting of acrylic monomers onto EVA copolymers 被引量:1
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作者 Zhang, S Wang, JQ +1 位作者 Xie, LQ Wen, CL 《Chinese Science Bulletin》 SCIE EI CAS 1997年第18期1549-1554,共6页
IN an ordinary way the grafting induced by electron and gamma preirradiations widely used for improving the compatibility of polymers in composites gives rise to an enhancement of their mechanical properties. However,... IN an ordinary way the grafting induced by electron and gamma preirradiations widely used for improving the compatibility of polymers in composites gives rise to an enhancement of their mechanical properties. However, very few have been reported in the flame retardancy of polymers using these sorts of techniques. Wilkie investigated the flame retardancy of photo-initiation grafted polymers. An attempt is made in this paper to try to use the EB preirradiation on EVA copolymers with different VA contents and the subsequent grafting with saponification under atmosphere and to expedite the charring of polymers upon heating. Characterization of the flammability of the preirradiated EVA copolymers grafted with acrylic monomers indicates that this approach turns out to be a promising way and worthy of doing. 展开更多
关键词 ELECTRON-BEAM IRRADIATION GRAFTING FLAME retardancy EVA copolymers.
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The pseudo-affine transformations in R^2
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作者 Li BaoKui Wang XianTao Wang YueFei 《Science China Mathematics》 SCIE 2010年第3期755-762,共8页
In this paper, we introduce the pseudo-affine transformations, a new class of maps, and obtain their characterization in terms of g-triangle-reflections.
关键词 AFFINE TRANSFORMATION pseudo-affine TRANSFORMATION g-triangle-reflection
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Collapse and revival in Aharonov-Bohm electron interference experiment
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作者 Jian Zou Bin Shao Xiusan Xing 《Chinese Science Bulletin》 SCIE EI CAS 1998年第18期1523-1527,共5页
It is shown that in the presence of even and odd coherent state field the collapse and revival (CR) phenomenon can occur in Aharonov_Bohm electron interference, which is closely related to the quantum fluctuation of t... It is shown that in the presence of even and odd coherent state field the collapse and revival (CR) phenomenon can occur in Aharonov_Bohm electron interference, which is closely related to the quantum fluctuation of the field. CR phenomenon reflects the effects of quantum noise of the field on the dynamic behaviour of electron interference. For coherent state field and number state field there is no CR to occur, which means that CR is due to both wave and particle aspects of the field. 展开更多
关键词 COLLAPSE and REVIVAL Aharonov_Bohm effect.
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