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131.
Various secondary and tertiary instabilities in plane channel flow are explored via time-dependent numerical simulations using the incompressible Navier-Stokes equations. Comparisons are made between transitional flows at Reynolds numbers 1500, 5000, and 8000. The lambda vortex, detached shear layer, and inverted vortex regions are identified and the origin of the latter is explained. The laminar breakdown of the Re=1500 flow is computed with high resolution and the nature of its ensuing hairpin eddies is clarified by numerical particle paths. The potential of center-mode rather than wall-mode transitions is proposed and the resulting flow structure is described. 相似文献
132.
The complex velocity field of an oscillating Couette flow is measured with a Laser-Doppler velocimeter. Different evaluation methods are used for the determination of material functions such as relaxation times and the dynamic complex viscosity. 相似文献
133.
本文给出了气垫船在静水中航行时稳态船波势问题的边界元数值分析方法,根据本文的数值计算方法,可以得到气垫船行时所兴起的波浪形状以及气垫附近流场情况,由此可计算气垫所受到的兴波阻力,本文的方法适用于任意已知气压分布情况。 相似文献
134.
135.
The antioxidant activity of a novel artificial glutathione peroxidase-like enzyme, selenium-containing glutathione 5-transferase
from Lucilia cuprina (seleno-LuGST1-1), was studied by using a ferrous sulfate/ascorbate-induced mitochondrial damage model system. Swelling of
mitochondria, lipid peroxidation, and cytochrome-c oxidase activity were selected to evaluate the preservation of mitochondrial integrity in this system. Seleno-LuGST1-1 could
effectively protect the mitochondria against oxidative damage in a dose-dependent manner and exhibited both higher catalytic
activity and greater antioxidant ability than the classic mimic, 2-phenyl-1,2-benziososelenazol-3(2H)-one (Ebselen). This
novel artificial biocatalyst therefore may have great protential for pharmacologic application in the treatment of reactive
oxygen species-related diseases. 相似文献
136.
137.
D. Y. Zang E. Rio D. Langevin B. Wei B. P. Binks 《The European physical journal. E, Soft matter》2010,31(2):125-134
We have investigated the rheological behaviour of silica nanoparticle layers at the air-water interface. Both compressed and
deposited layers have been studied in Langmuir troughs and with a bicone rheometer. The compressed layers are more homogeneous
and rigid, and the elastic response to continuous, step and oscillatory compression are similar, provided the compression
is fast enough and relaxation is prevented. The deposited layers are less rigid and more viscoelastic. Their shear moduli
deduced from the oscillatory uniaxial compression are much smaller than those deduced from pure shear deformation suggesting
that the effective shear rate is smaller than expected in the compression measurements. 相似文献
138.
Photocurrent analysis of organic photovoltaic cells based on CuPc/C60 with Alq3 as a buffer layer 下载免费PDF全文
The performance of an organic photovoltaic(OPV) cell based on copper phthalocyanine CuPc/C60 with a tris(8-hydroxyquinolinato) aluminum(Alq3) buffer layer has been investigated.It was found that the power conversion efficiency of the device was 1.51% under illumination with an intensity of 100 mW/cm2,which was limited by a squareroot dependence of the photocurrent on voltage.The photocurrent-optical power density characteristics showed that the OPV cell had a significant space-charge limited photocurrent with a varied saturation voltage and a three quarters power dependence on optical power density.Also,the absorption spectrum was measured by a spectrophotometer,and the results showed that the additional Alq3 layer has a minor effect on photocurrent generation. 相似文献
139.
Chloroform-vapor annealing of thin films of propoxyethyl perylene tetracarboxylic diimide (PE-PTCDI, an n-type semiconductor) deposited on glass or mica leads to formation of well-defined one-dimensional self-assemblies (e.g. nanobelts), which show optically uniaxial properties as demonstrated by the linearly polarized emission. 相似文献
140.
As the surface polaritons are excited in Kretschmann configuration with a Kerr-type substrate, the nonlinear Goos-Hänchen (GH) shifts exhibit the optically hysteretic response to the intensity of incident light. For thicker metal films, the GH shifts become very sensitive to the intensity of incident light and the angle of incidence. 相似文献