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民族国家构建视阈下的乌克兰危机研究 被引量:1
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作者 周俊华 何志斌 《云南行政学院学报》 北大核心 2016年第3期33-41,共9页
持续发酵的乌克兰危机牵动着全世界的神经,带动着全球政治力量的博弈,深刻影响着国际关系。乌克兰民族问题由来已久,民族、历史、宗教、政治、文化等因素长期交织是乌克兰民族问题形成的历史根源,乌克兰独立后的政治民主化进程中,"... 持续发酵的乌克兰危机牵动着全世界的神经,带动着全球政治力量的博弈,深刻影响着国际关系。乌克兰民族问题由来已久,民族、历史、宗教、政治、文化等因素长期交织是乌克兰民族问题形成的历史根源,乌克兰独立后的政治民主化进程中,"橙色革命"、"蓝色革命"的相继上演,"引爆"了乌克兰危机。基于民族国家构建的视阈来分析,因地理、历史因素产生的区域主义现实,因社会"特性"分裂而导致乌克兰的"国家性"问题,使其民族构建面临困境;国家政治制度设计上的缺陷,在政体上的左右徘徊,脆弱的政党政治使其国家构建产生严重的问题。研究乌克兰危机对多民族国家有效治理民族问题、防止国家分裂具有借鉴意义。 展开更多
关键词 民族国家 乌克兰危机 “国家性”问题 “特性”分裂
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Chaotic characteristics of electromagnetic emission signals during deformation and fracture of coal 被引量:8
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作者 NIE Bai-sheng HE Xue-qiu +2 位作者 LIU Fang-bin ZHU Cheng-wei WANG Ping 《Mining Science and Technology》 EI CAS 2009年第2期189-193,共5页
Electromagnetic emission(EME) is a kind of physical phenomenon accompanying the process of deformation and fracture of loaded coal and rock and it is of importance in quantitatively analyzing its characteristics.This ... Electromagnetic emission(EME) is a kind of physical phenomenon accompanying the process of deformation and fracture of loaded coal and rock and it is of importance in quantitatively analyzing its characteristics.This will reveal the process of deformation and fracture of coal and predicting dynamic disasters in coal mines.In this study,the G-P(Grassberger and Procaccia) algorithm,calculation steps of the(if only 1 dimension) correlation dimension of time series and the identification standards of chaotic signals are introduced.Furthermore,the correlation dimensions of EME and the acoustic emission(AE) signals of time series during deformation and fracture of coal bodies are calculated and analyzed.The results show that the time series of pulses number of EME and the time series of AE count rate are chaotic and that the saturation embedding dimensions of a K3 coal sample are,respectively,5 and 6.The results can be used to provide basic parameters for predicting of EME and AE time series. 展开更多
关键词 coal and rock electromagnetic emission correlation dimension chaotic characteristics
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Purification and characterization of schizophyllan from Schizophyllum commune
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作者 Hao Limin Zhang Jianchun +5 位作者 Wu Tianyi Zhang Jian Lu Jike Wang Qizhi Zhang Xiaojuan Xing Xinhui 《Engineering Sciences》 EI 2013年第2期88-92,共5页
The schizophyllan from Schizophyllum commune was purified and characterized. The crude schizo-phyllan was obtained from Schizophyllum commune fermentation broth by decoloration with activated carbon,followed by deprot... The schizophyllan from Schizophyllum commune was purified and characterized. The crude schizo-phyllan was obtained from Schizophyllum commune fermentation broth by decoloration with activated carbon,followed by deproteinization with Sevag method and ethanol precipitation. The pure schizophyllan was obtained by gel filtration chromatography with Sephacryl S-500,and its molecular characteristics were examined. The result showed that the molecular weight was 3.8×104 ,and the schizophyllan consisted of glucose with β-(1→6)-glucosidic linkages. 展开更多
关键词 SCHIZOPHYLLAN Schizophyllum commune PURIFICATION CHARACTERIZATION
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Study on the S-wave Splitting Characteristics in the Longtan Reservoir Area,Guangxi,China
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作者 Shi Haixia Zhao Cuiping 《Earthquake Research in China》 2011年第2期213-226,共14页
In this paper,the shear wave splitting features of the Longtan reservoir area are studied by adopting the traditional cross-correlation coefficient method and polarization analysis,using the data recorded by the seism... In this paper,the shear wave splitting features of the Longtan reservoir area are studied by adopting the traditional cross-correlation coefficient method and polarization analysis,using the data recorded by the seismic network founded by a project under the National Science and Technology Pillar Program from April 2009 to April 2010.We found that most of polarization directions at seismic stations are consistent with the direction of the overall regional stress field,but local structures and faults may control or influence the fast shear-wave polarization direction.The time-delay normalized to source-station path is between 10 to 25ms/km,and among them,the time-delay is about 10ms/km at the LIL and XIL sites,which are farther away from the dam.The water depth is relatively shallow and seismic activity relatively weak after water storage,indicating the effect of reservoir water penetration,or loading,on the state of cracks in the reservoir area.We also found that the delay time changes consistently with the water level at stations DPD and GAL.It may be related to crack expansion and water penetration caused by the reservoir impoundment. 展开更多
关键词 Longtan reservoir Seismic anisotropy Shear-wave splitting Fast shear-wavepolarization direction Delay time
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Breakup Structure of Two-phase Jets with Various Momentum Flux from a Porous Injector 被引量:2
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作者 Inchul Lee Dohun Kim Jaye Koo 《Journal of Thermal Science》 SCIE EI CAS CSCD 2014年第1期60-67,共8页
Spray structure and atomization characteristics were investigated through a comparison of a porous and a shear coaxial injector. The porous injector shows better atomization performance than the shear coaxial injector... Spray structure and atomization characteristics were investigated through a comparison of a porous and a shear coaxial injector. The porous injector shows better atomization performance than the shear coaxial injector. To in- crease atomization performance and mixing efficiency of two-phase jets, a coaxial porous injector which can be applicable to liquid rocket combustors was designed and tested. The characteristics of atomization and spray from a porous and a shear coaxial injector were characterized by the momentum flux ratio. The breakup mechanism of the porous injector is governed by Taylor-Culick flow and axial shear forces. Momentum of injected gas flow through a porous material which is composed of sintered metal is radically transferred to the center of the liquid column, and then liquid column is effectively broken up. Although the shapes of spray from porous and shear co- axial jets were similar for various momentum ratio, spray structures such as spray angle and droplet sizes were different. As increasing the momentum flux ratio, SMD from the porous injector showed smaller value than the shear coaxial injector 展开更多
关键词 Porous injector Shear coaxial injector Breakup mechanism Momentum flux ratio
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The effect of volatile components in oil on evolutionary character- istics of diamondoids during oil thermal pyrolysis
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作者 FANG ChenChen XIONG YongQiang +3 位作者 LI Yun LIANG QianYong WANG TongShan LI YongXin 《Science China Earth Sciences》 SCIE EI CAS CSCD 2016年第2期362-370,共9页
On the basis of the results of simulation experiments, now we better understand the contribution of high carbon number hydrocarbons to diamondoid generation during thermal pyrolysis of crude oil and its sub-fractions(... On the basis of the results of simulation experiments, now we better understand the contribution of high carbon number hydrocarbons to diamondoid generation during thermal pyrolysis of crude oil and its sub-fractions(saturated, aromatic, resin, and asphalene fractions). However, little is known about the effect of volatile components in oil on diamondoid generation and diamondoid indices due to the lack of attention to these components in experiments. In this study, the effect of volatile components in oil on diamondoid generation and maturity indices was investigated by the pyrolysis simulation experiments on a normal crude oil from the HD23 well of the Tarim Basin and its residual oil after artificial volatilization, combined with quantitative analysis of diamondoids. The results indicate that the volatile components(≤n C12) in oil have an obvious contribution to the generation of adamantanes, which occurs mainly in the early stage of oil cracking(Easy Ro<1.0%), and influences the variations in maturity indices of adamantanes; but they have no obvious effect on the generation and maturity indices of diamantanes. Therefore, some secondary alterations e.g., migration, gas washing, and biodegradation, which may result in the loss of light hydrocarbons in oil under actual geological conditions, could affect the identification of adamantanes generated during the late-stage cracking of crude oil, and further influence the practical application of adamantane indices. 展开更多
关键词 Crude oil Volatile component Thermal pyrolysis DIAMONDOIDS Evolution characteristics
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