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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.
为了找出适用于再循环重力供液蒸发器管内强制对流沸腾换热系数的关系式,通过对以R404A为制冷剂的重力供液实验台的研究,编程计算出J.Chawla关系式及Shah关联式对重力供液沸腾换热系数进行预测值。与实验结果比较可知:J.Chawla关系式在较低温度下较接近于实验值,Shah关联式在较高的温度下可以对实验值进行预测,两种关系式相结合的方法就可以较好对重力供液蒸发器管内沸腾换热进行预测。  相似文献   
144.
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.
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.
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.
Wong GK  Zang L  Kang MS  Russell PS 《Optics letters》2010,35(23):3982-3984
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   
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