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991.
William Faulkner's non-chronological story tellingstyle has long been a challenge to critics and apuzzle to beginning literature students. ``A Rose forEmily,'' one of Faulkner's most frequently anthologizedstories, exemplifies the complexity of Faulkner'streatment of time. In this paper, we apply aconstraint-based problem solving method to an analysisof the chronology of ``A Rose for Emily.'' Constraintlogic programming is a declarative programminglanguage paradigm that solves problems by enforcingconstraints among variables. CLP's ability to sortnumeric variables that do not yet have definite valuesmakes it possible to sort the events of ``A Rose forEmily'' with only fragmented and relative timeinformation. In attempting to sort the events of thestory, we find an inconsistency in the temporalreferences scattered throughout the narrative. Afterremoving this inconsistency, we are able to compareour chronology with earlier ones and discuss thethematic relevance of Faulkner's nonlinear plots. 相似文献
992.
本文研究了缩减自由度的逐步积分方法,导出了它的截断误差表达式,并与振型迭加和Wilson—θ法直接积分进行了比较,表明了方法对大型结构地震反应分析的有效性。并在线弹性假定下,用低弹模模拟坝基中的软弱带,分析计算了这种非均匀地基的软弱带对重力坝动力时程反应的影响,与均匀地基上重力坝的结果进行了比较。 相似文献
993.
Microorganism cells could be used as templates during fabrication of magnetic or conductive microstructures in different standard
shapes. In this paper, feasibility of magnetizing microorganism cells by sol-gel method, which is to coat cells of Spirulina (a type of natural micro-helical microorganism) with the ferrite (a kind of magnetic material), was discussed and investigated.
Then the cell form, components and the phase structure were observed and analyzed using various tools including optical microscopy,
scanning electron microscopy (SEM), energy dispersive X-ray detector (EDX), transmission electron microscopy (TEM), and X-ray
diffraction analysis (XRD). Results showed that spirulina cells could be coated with ferrite after the sol-gel process, with the shape of natural helixes well kept, that the components
of different sampling points on the surface layer were consistent and the thickness of layer was uniform, and that the type
of the surface ferrite layer formed was cubic Fe3O4. It was also observed that there were nano-particles yielded in the cells and certain deposit on the walls between cells.
The kinetics of the cell magnetization technology by sol-gel was also discussed.
Supported by the National Natural Science Foundation of China (Grant No. 59975007), the National Hi-Tech Research and Development
Program of China (863 Program) (Grant No. 2001AA421120), and the Innovative Fund of Beihang University in 2005 (Grant No.
200505) 相似文献
994.
利用 Goldschmidt 因子计算具有垂直铁电(F)反铁电(AF)相界的 PSZT 三元系材料,并由实验证实。透射电镜观察到 F、AF 两相在同一晶粒内共存。用电滞回线、热释电、介电等方法测试了该相界附近材料的宏观电性能,研究了它们在外电场和静压力下的诱导相变行为及变化规律。 相似文献
995.
996.
This paper mainly focuses on cross-effect of heat and mass transfer of capillary porous media which A.B.Luikov set up on irreversible thermodynamics principle. On the basis of perfecting the equations of heat and mass transfer, the heat and mass transfer parameters are determined during drying processes, and thermal gradient coefficient δ and moisture gradient coefficient ξ are obtained which show the cross-effect of heat and mass transfer. Thus the fundamentals are provided for quantitative analysis of cross-effect of heat and mass transfer. The convective drying mathematical model under the first unsteady boundary condition is therefore proposed. By the application of Henry transform, the theoretical solution of unsteady drying process is given and its validity is verified 相似文献
997.
998.
β-tricalcium phosphate nanoparticles adhered carbon nanofibrous (β-TCP@CNFs) membranes were prepared by electrospinning and sintering a mixed solution of triethylphosphate, calcium nitrate tetrahydrate, and PAN. Crystalline structure and morphology of β-TCP@CNFs were characterized by XRD, SEM, and TEM observations. The diameter of the β-TCP nanoparticles was in the range of 30-60 nm, they were well distributed on the surface of CNFs. Human osteoblasts cells were actively proliferated on the β-TCP@CNFs membrane due to the far extended adhesion area and biocompatibility. 相似文献
999.
We present an analysis of the steady-state operation of a two-element coupled-cavity laser near a mode hop. The equations of motion for the two cavities and two relevant modes of a longitudinally coupled-cavity laser are reduced to a system of nondimensional nonlinear ordinary differential equations which describe a general two-element laser. The equations are then solved and the stability of their solutions is analyzed. Depending upon the fill factors for the two modes, there exists an intrinsically multimode oscillation for operating conditions under which it was previously thought that no steady state existed. Under conditions where the multimode state is unstable, both of the single-mode states are stable with bistable transitions occurring only on the boundaries of the unstable multimode regimes. 相似文献
1000.