裂变性创新的内涵辨析

裂变性创新研究逐步扩大深化,理论研究需要先对概念的实质内涵进行深入剖析,才能在此基础上深入研究。在回顾裂变性创新多种类型定义的基础上,归纳裂变性创新的共同特点。通过对技术创新集合的划分,探讨四种技术创新之间的内在关系,借助讨论和区分四种创新之间相互交错包含关系,更为清晰的阐述裂变性创新的实质内涵。

民营企业裂变性创新应用中的经营风险防范

民营企业裂变性创新在带来新增长机遇的同时也带来新风险,主要集中在业务多元化、资金链、新业务模式和经营管理等方面。这些风险并不是裂变性创新应用独特产生的,是由于裂变性的新市场突破、低端突破以及业务高速发展等特点将风险成倍放大所造成。民营企业进行裂变性创新时应加强对此的防范。

主体意识的归隐 显现与本质寻求——意识形态的质性裂变

随着意识形态理论的发展,意识形态的所指已经发生了实质性的功能性裂变。它的发生逻辑隐含了主体意识的无意识的归隐与自为的显现,而主体意识与意识形态的本质寻求无论是隐匿性的暗示或遮蔽性的深层所指,都与意识形态的功能性机制及社会历史性的存在状况具备极强的内在一致性。

从媒介语言的角度解读网络论坛

互联网在催生数亿网民的同时,也孕育了一大批斯潮的网络语言。网络论坛作为一种不断成熟的事物,与之相对应的语言也成为一种特殊的文化现象。网络论坛语言是形成于网络论坛并应用于网络社区交往的一种媒介语言,有着自己的特点和魅力。因其草根性和互动性的特点,具有强大的生命力和表现力,它既形象生动又能推动"传播赋权":因其地方性和裂变性的特点,它既有地方特色又能发展演变易于接受,很快席卷所有网络论坛。

微博舆情的传播特征

微博舆情是民众在微博空间里的舆论反映。近年来,民众借助微博表达意见、讨论公共事务、维护公民权力的事件屡见不鲜。微博舆情成为反映社会现实的一种"镜像"。它具有传播主体的去中心化与圈子化、传播内容的理性与非理性、传播过程的阶段性与周期性、传播路径的点对面与裂变性等特征。微博舆情的发酵,聚焦了网络民意,成为舆论演进的助推器,构筑起全新的社会舆论形态。

Failure mechanism of as-cast Mg-6Zn-2Er alloy during tensile test at room temperature

Tensile test of the as-cast Mg-6Zn-2Er alloy was conducted at room temperature. The results indicate that the alloy is inclined to failure when the strain reaches 5.6%. The coarse secondary phases are responsible for the failure, especially for the Mg3Zn3Er2 phase （W-phase）. It is indicated that the existence of the W-phase activates the stress concentrations due to the incapacity of W-phase for the load transfer, which results in the void at the inner of the W-phase. In comparison, the interface between the matrix and the secondary phase is stable. In conclusion, the characters of the secondary phases with respect to size, distribution, morphology and type, play an important role in the plastic deformation behavior of the alloy.

Effects of plastic deformation on precipitation behavior and tensile fracture behavior of Mg-Gd-Y-Zr alloy

The effects of plastic deformation on precipitation behavior and tensile fracture behavior of Mg-10Gd-3Y-0.6Zr alloy were investigated.The results indicate that more precipitation cores can be provided by the crystal defects caused by the plastic deformation,as well as increasing the amount of β＇ phases,and the formation of precipitations at grain boundaries and interfaces between the twins and matrix.Because of an increase in precipitations,the dislocation slipping during deformation process is effectively hindered and the matrix is strengthened,especially for the 2% deformed alloy which can achieve a good combination of strength and ductility.With increasing the plastic deformation,the microcracks occur at the interface between grain boundary precipitations and matrix,and then propagate intergranularly.When intergranular fracture combines with the formation of smoothing facets on the fracture surface,the tensile properties decrease.

新媒体视角下媒体策划事件的传播特点

在新媒体视角下,媒体策划事件呈现出互动性、裂变性等新的传播特点,利用好这些特点开展相应的媒体策划,能够起到事半功倍的效果。

Numerical simulation of ductile fracture behavior for aluminum alloy sheet under cyclic plastic deformation

A numerical analysis of mechanical behavior of aluminum alloy sheet under cyclic plastic deformation was investigated.Forming limit at fracture was derived from Cockcroft-Latham ductile damage criterion.The strain path of bending center of incremental roller hemming could be accepted as a kind of plane strain bending deformation process.Incremental rope roller hemming could be used to alleviate ductile fracture behavior by changing the stress state of the hemming-effected area.SEM observation on the fracture surface indicates that cyclic plastic deformation affects ductile fracture mechanism.

Variation of the second-phase morphology and its influence on fracture behavior of Al-Si alloy

Using an optical microscope and scanning electron microscope (SEM), the variation of eutectic Si morphology of Al-Si alloy in solution treatment was observed to study its influence on mechanical properties and fracture behavior. The results show that eutectic Si undergoes stubbing, necking, fragmentation, and growth in the initial stage (250 min); in the middle solution stage (250 to 400 min), the eutectic Si morphology has no significant change, only the degree of spheroidizing becomes higher; after 600 min, the growth of eutectic Si is a coarsening process controlled by diffusion and follows the Liftshitz-Slyozov-Wangner (LSW) model, and the eutectic Si morphology deteriorates due to the occurrence of facets and lap. Based on the quantitative measure and regression analysis, the eutectic Si morphology has a remarkable influence on mechanical properties and fracture behavior.

Dynamic behavior and fracture mode of TiAl intermetallics with different microstructures at elevated temperatures

Experimental studies were conducted on the tensile behaviors and fracture modes of TiAl（Ti-46.5Al-2Nb-2Cr） alloys with near gamma（NG） equiaxed and near lamellar（NL） microstructures over a temperature range from room temperature to 840 ℃ and a strain rate range of 0.001-1 350 s-1.The results indicate that the alloys are both temperature and strain rate dependent and they have a similar dependence.The dynamic strength is higher than the quasi-static strength but almost insensitive to high strain rate range of 320-1 350 s-1.The brittle-to-ductile transition temperature（BDTT） increases with increasing strain rates.NG TiAl yields obviously,while NL TiAl does not.Below BDTT,as the temperature increases,the fracture modes of the two alloys change from planar cleavage fracture to a mixture of transgranular and intergranular fractures,and finally to totally intergranular fracture.

俄罗斯和美国建立防止核材料失窃的系统

【《国际原子能机构每日文摘》1996年第82期报道】 据俄罗斯新闻机构《Interfax》报道,俄罗斯和美国核物理学家已同意一道工作,来建立防止核材料失窃的新系统。该机构援引俄罗斯奥布宁斯克物理和能源研究所的物理学家Gennadiy Pshakim的话说,将在美国利弗莫尔和洛斯阿拉莫斯核实验室专家的帮助下建立的这个系统,将跟踪该研究所内的所有可裂变性材料的移动情况。目前。

Plastic anisotropy and fracture behavior of AZ31 magnesium alloy

The effects of texture and abnormal large grains on the plastic anisotropy and fracture behavior of hot-rolled AZ31 magnesium alloy were investigated. Uniaxial tensile deformation behaviors of samples with tensile axis tilting 0°, 15°, 30°, 45°, 60°, 75° and 90° to normal direction （ND） respectively were addressed. Tensile deformation anisotropy was observed for samples with different angles to ND. The results show that the specimens with the angle from 0° to 30° exhibit relatively lower yielding strength due to the {1 012}extension twinning. However, basal slip and prismatic slip are the dominant deformation modes for the specimens with angles larger than 45°. Macro-fractures are parallel to the length direction of abnormal large grains in the specimens with angles less than 60°, while those are serrated fracture edge for specimens with angles 75° and 90°.

Representation Theory of Three-Dimensional Elliptical Crack Under Dynamic Loading

The relation between the normal displacement on the surface of a dynamical elliptical crack and the normal stress over the crack surface was studied. The three dimensional elastodynamic equations and Fourier Laplace transforms are used. Based on the influence function and the inversion of integral transforms, one can find that if the distribution of normal displacement on the surface of a dynamic elliptical crack is a polynomial of degree n in x 1 and x 2 , then the normal pressure acting over the ellipse is also a polynomial P n(x 1,x 2) of the same degree in x 1 and x 2 .

Analysis of deformation ＆ destruction mechanism and stability of F0 fault crush zone in Fangezhuang Coal Mine

Under the mining influence, carried on the electron microscope, the thin section analysis and creep tests to the fault matter＇s original sample and five groups of duplication samples, which have three kinds of moisture. The results of those tests indicate that confining pressure effect, structure effect and moisture effect all have influence to fault matter＇s nature. Meanwhile, the distortion destruction and stability variation of fault crush zone are the main reason which causes water-inrush lag-effect. Simultaneously, the stimulation computation we made by the numerical simulation software FLAC 3D also describes the mining influence to floor strata, fault crush zone＇s range and size, the influence of confined water on overburden and the fault zones, also it describes the time effect of bearing influenced by confined water and the rock dank height of confined water along the fault zones influenced by the specific water head.

Equivalent elastic compliance tensor for rock mass with multiple persistent joint sets:Exact derivation via modified crack tensor

Discontinuities constitute an integral part of rock mass and inherently affect its anisotropic deformation behavior.This work focuses on the equivalent elastic deformation of rock mass with multiple persistent joint sets.A new method based on the space geometric and mechanical properties of the modified crack tensor is proposed,providing an analytical solution for the equivalent elastic compliance tensor of rock mass.A series of experiments validate the capability of the compliance tensor to accurately represent the deformation of rock mass with multiple persistent joint sets,based on conditions set by the basic hypothesis.The spatially varying rules of the equivalent elastic parameters of rock mass with a single joint set are analyzed to reveal the universal law of the stratified rock mass.

Performance of EDAB-HCl Acid Blended System as Fracturing Fluids in Oil Fields

Due to the high price and formation damage of the guargum fracturing fluid, many oilfields are more and more interested in surfactant based fracturing fluids. The rheological properties of erucicamide dimethyl amidopropyl betaine （EDAB）-HC1 acid blended system and its suitability as fracturing fluid were investigated in this work. The effects of pH, concentration of EDAB, and temperature on the rheological properties of the blended system were studied. The results show that addition of EDAB improved the viscosity of the system from less than 10 mPa. s to about 400 mPa. s, which could retard the acid-rock reaction to about one half at 60℃ and one quarter at 90℃ comparing to straight HC1 acid, suggesting that there is sufficient time for the blended fluid to react with formation rock when it is used as fracturing fluid in an oil field. Core flow tests demonstrated that the EDAB-acid blended fluid could divert itself from high permeability formation core to low permeability one, thus ensuring proper acid placement in the target reservoirs.

Half-Lives for Alpha Radioactivity of Elements with 104 ≤Z≤120 within Unified Fission Model

α decay half-lives are calculated using the Qα values obtained by Semi-empirical Shell Model in the framework of the Unified Fission Model （UFM） with the Coulomb repulsion, nuclear attraction due to proximity potential, and rotational energy due to angular momentum transfer of a particle. In addition, the calculated and experimental half-lives of 425 nuclei are compared to check the validity of the model applied on α decay. The calculated half-lives of decay are in good agreement with the experimental data. Finally, some useful predications on the α decay half-lives are provided for future experiments.

Chaotic characteristics of electromagnetic emission signals during deformation and fracture of coal

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.