[en] A bilayer CdS/ITO film was obtained. The dipped CdS was grown by an ultrasonic colloid deposition (USCD) method. Microstructure of the CdS film made by USCD has a wider transmission range and a higher transmittance. Amorphous indium-tin-oxide (ITO) thin film was deposited using d.c. magnetron-sputtering at room temperature. The ITO films exhibited good conductivity and maximum transmittance of 94%. The CdS/ITO bilayer was investigated by means of GIXD (grazing incidence X-ray diffraction) at different incidence angles (α=0.20-5.00 deg.) and XRD. We discuss a model for the thin bilayer film. SEM and AFM show that homogeneous CdS films with a bar-shaped ultrafine particles and ITO film with nanometer structure. The mechanism of the bilayer CdS/ITO film is discussed

[en] Based on the phenomenon of chlorophyll a photoluminescence, this paper introduces a new method to measure the chlorophyll a content, using 660nm laser diode as a new kind of light source to stimulate fluorescence as well as combining a fiber and spectrum technique. We analyze the characteristics of laser-induced fluorescence spectrum of chlorophyll a and then put forward the new method using two parameters, the relative fluorescence intensity and fluorescence intensity ratio F685/F735, to measure the chlorophyll a content in the water and green leaves respectively. The experimental results indicate that it is completely feasible to give a visual judgment for chlorophyll a content, according to the fluorescence emission spectrum of chlorophyll a. Subsequently, it is verified by three kinds of typical applications. All of these provide a new kind of light source to develop the chlorophyll a fluorometry and further give a technical foundation of on-spot monitoring the chlorophyll a content in the ocean or in green leaves

[en] An atomic force microscope (AFM) and spectrometer combined system for in-situ thickness measurement of nano-porous alumina (PA) films is introduced. The AFM is applied to obtain the porosity of PA film, and then we calculate the effective refractive index by Maxwell-Garnett effective dielectric constant theory. The optical thickness of PA film is determined by reflective interference spectrometer. The PA film thickness can also be measured via scanning the crosssection with optical microscope and scanning electron microscope (SEM). The sample will be damaged, however, when using this method. The measurement by optical microscope is convenient, but it's hard to attain high resolution. When using SEM, the sample surface must be gilt and needs a vacuum environment. The system we developed can avoid the disadvantages of the method. It realizes non-destructive and highresolution in-situ measurement

[en] At present, the main test technique of AIDS is PA in China. Because the judgment of PA test image is still depending on operator, the error ration is high. To resolve this problem, we present a new technique of image processing, which first process many samples and get the data including coordinate of center and the rang of kinds images; then we can segment the image with the data; at last, the result is exported after data was judgment. This technique is simple and veracious; and it also turns out to be suitable for the processing and analyzing of other infectious diseases' PA test image

[en] In bioreactor landfills, pressured leachate re-circulation can significantly influence the process of stabilization and the slope stability. To accelerate the leachate re-circulation and avoid slope failure, in this study, construction of a spatial reinforcement net is proposed, which consists of bonded whole waste tyres during municipal waste landfill. A coupled dual-permeability model and equilibrium equation were used to examine the enhanced leachate distribution and the local factor of safety of slope stability for a simplified bioreactor landfill. The simulation results demonstrated that for similar injection efficiency, the waste tyres net can help to decrease the amount of horizontal trenches and allows higher injection pressure under conditions of intermittent re-circulation. By virtue of waste tyres, the slope stability was considerably improved even when being exposed to a higher injection pressure. (paper)

[en] At present the main problems of polymer flooding is the high injection pressure which could not guarantee the later injection. In this paper the analyses of polymer’s physical properties and its solution’s variable movement characteristics in porous media reveal the inevitable trend of decrease in injection capacity and liquid production due to the increase of fluid viscosity and flow rate with more flow resistance. The injection rate makes the primary contribution to the active viscosity of the polymer solution in porous media. The higher injection rate, the greater shearing degradation and the more the viscosity loss. Besides the quantitative variation, the rate also changes qualitatively as that the injection rate demonstrates composite change of injection intensity and density. Due to the different adjustment function of the polymer solution on its injection profile, there should be different adjustment model of rates in such stages. Here in combination of the on-site recognitions, several conclusions and recommendations are made based on the study of the injection pattern adjustment during polymer flooding to improve the pressure distribution system, which would be a meaningful reference for extensive polymer flooding in the petroleum industry. (paper)

[en] We report the effect of superconductivity on the characteristics of a YBa₂Cu₃O_7-δ/0.7 wt% Nb-doped SrTiO₃ heterojunction. This junction shows a good rectifying property in the current-voltage (I-V) characteristics. With the superconducting transition, the temperature dependence of the junction resistance shows a decrease and the diffusion voltage has a flat step. The capacitance and loss of the junction show jumps at the superconducting transition temperature (T_c) and these jumps can be suppressed by a magnetic field. In addition, with an increase in the measuring frequency, the capacitance of the junction decreases and the capacitance jumps at the T_c increase. Analysis of the I-V curves suggests the existence of inhomogeneity in the heterojunction, which can account for the effect of superconductivity on the characteristics of the heterojunction. This work is helpful in understanding the effect of superconductivity on the characteristics of superconductor heterojunctions

[en] Underwater friction stir welding (FSW) has been demonstrated to be available for the improvement in tensile strength of normal FSW joints. In order to illuminate the intrinsic reason for strength improvement through underwater FSW, a 2219 aluminum alloy was underwater friction stir welded and the homogeneity of mechanical properties of the joint was investigated by dividing the joint into three layers. The results indicate that the tensile strength of the three layers of the joint is all improved by underwater FSW, furthermore, the middle and lower layers have larger extent of strength improvement than the upper layer, leading to an increase in the homogeneity of mechanical properties of the joint. The minimum hardness value of each layer, especially the middle and lower layers, is improved under the integral water cooling effect, which is the intrinsic reason for the strength improvement of underwater joint.

[en] Pressures vessel are widely used in the modern industry. It is important to measure pressure of vessels. It has been proved that the change of ultrasonic velocity can be used to detect the stress of the material, and the velocity change can be obtained by estimating the time delay of two ultrasonic pulses. In this paper, the Rayleigh wave is selected as the ultrasonic pulse. Because the Rayleigh wave usually contains noise which deteriorates the estimation precision of the time delay, a signal processing method has to be used. Compared with the continuous wavelet transform, the correlative time estimation method based on the Hilbert-Huang Transform is presented in order to calculate the transit time difference. The experiments results show that this method can improve the accuracy of the time estimation

[en] Monodispersed Co nanoclusters have been grown on a graphene moire on Ru(0001) at room temperature. Scanning tunneling microscopy measurements showed that the Co clusters nucleate at both the fcc and hcp regions. Co forms finely dispersed small three-dimensional (3D) clusters on graphene/Ru(0001), and a defined long-range ordering of Co nanoclusters with increasing coverage is not observed. The size distribution of the clusters is narrow and the size of the clusters is tunable. The absorbed Co begins to intercalate between the graphene layer and the Ru(0001) substrate when annealing the sample at temperatures up to about 473 K.