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141.
142.
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
143.
144.
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
145.
Photocurrent analysis of organic photovoltaic cells based on CuPc/C60 with Alq3 as a buffer layer
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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
146.
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
147.
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
148.
Metal nanocluster composite glass prepared by 180 keV Cu ions into silica with dose of 1 × 1017 ions/cm2 has been studied. The microstructural properties of the nanoclusters were analysed by optical absorption spectra and transmission electron microscopy (TEM). Third-order nonlinear optical properties of the nanoclusters were measured at 1064 nm and 532 nm excitations using Z-scan technique. The nonlinear refraction index, nonlinear absorption coefficient, and the real and imaginary parts of the third-order nonlinear susceptibility were deduced. The mechanisms responsible for the nonlinear response were discussed. Absolute third-order nonlinear susceptibility χ(3) of this kind of sample was determined to be 2.1 × 10−7 esu at 532 nm and 1.2 × 10−7 esu at 1064 nm, respectively. 相似文献
149.
Qinmin Guo Zhihui Qin Cunding Liu Kan Zang Yinghui Yu Gengyu Cao 《Surface science》2010,604(19-20):1820-1824
Bias-dependent features of the insulating NaCl layer grown on Cu(001) have been investigated by scanning tunneling microscopy/spectroscopy (STM/STS). The apparent layer thickness of the NaCl film is variable at bias voltages ranging from 2.8 to 3.2 V as well as from 4.0 to 5.0 V, and the Moiré pattern induced by NaCl–Cu lattice mismatch also shows bias dependence. The z–V (dz/dV–V) curves and dI/dV mapping measurements reveal that the resonant tunneling between the image potential states (IPSs) on Cu(001) and the Fermi level of the STM tip leads to drastic variations of these features. 相似文献
150.
We use low-coherence interferometry to measure the group-velocity dispersion (GVD) of the fast and slow Bloch modes of structural rocking filters, produced by twisting a highly birefringent photonic crystal fiber to and fro while scanning a focused CO(2) laser beam along it. The GVD curves in the vicinity of the resonant wavelength differ dramatically from those of the unperturbed fiber, suggesting that rocking filters could be used in the optimization of, e.g., four-wave mixing and supercontinuum generation. Excellent agreement is obtained between theory and experiment. 相似文献