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Profile control and flooding technique is an effective way to enhance the oil recovery of low permeability reservoir.Analyzing the relation between oil and water interface and determining injection volume under different concentration is the key to success in profile controlling and flooding in low permeability reservoir .The research is about SJT-B collosol of physicochemical property under normal pressure and temperature.We also carry on the study on measuring SJT-B collosol interfacial tension for a long time under different concentration.Besides, we conduct the plugging degree experiment by injecting SJT-B collosol with the concentration of 0.8% in different permeability core.The lower the core permeability, the higher the plugging degree. By optimizing the injection pattern we conduct the three-tube parallel profile control and flooding experiment in the low permeability heterogeneous core.It indicates that SJT-B collosol mainly access to high permeability layer and have an effective plugging effect .The absorbed liquid rate of medium permeability layer is increased apparently ,while low permeability layer is increased slightly.The SJT-B collosol of injection method has efficient effect on enhancing the oil recovery of low permeability reservoir in late water flooding.

Ba0.2Sr0.8Co0.9Nb0.1O3-δ(BSCN0.2)-xGd0.1Ce0.9O1.95(GDC) (x = 10, 20, 30 and 40 wt.%) composite cathodes were investigated for the potential application in the IT-SOFCs. The results of chemical compatibility measurement show that a small number of Gd and/or Ce ions may melt into the lattice of BSCN0.2 to form BSCN0.2-GDC solid solution. Thermal expansion coefficients effectively reduced by the incorporation of GDC. The electrochemical performance of BSCN0.2-xGDC composite cathodes increased with increasing x from 10 to 30 wt.%. When x = 30 wt.%, the area specific resistances were only 0.040 and 0.017 Ω cm2at 750 and 800oC, respectively. This improved electrochemical performance is attributed to the good thermal expansion match between BSCN0.2-xGDC composite cathode and GDC electrolyte, and the increased oxygen vacancy concentration. With further increasing x, the electrochemical performance of the composite cathode decreased. This result may be due to the ambipolar resistance model of porous composite cathode and the poor electrical conductivity of BSCN-40GDC. The maximum power densities of a BSCN0.2-30GDC/La0.9Sr0.1Ga0.8Mg0.2O3-δ/NiO-Sm0.2Ce0.8O1.9single-cell achieve 537 and 722 mW cm-2at 750oC and 800oC, respectively. These results indicate that the BSCN0.2-30GDC composite cathode is a promising candidate for IT-SOFC.

As the distribution energies are becoming the future trend to solve the tense fossil fuel supplying and environmental issues, further research on the management of DGs connected to system is necessary. Management of reactive power resources is vital for stable and secure operation of power systems in power losses and voltage quality. Base on this, an optimal power allocation strategy of different types of DG units which result in the minimum line losses and relatively good voltage profile is proposed in this paper.

Bioactive calcium phosphate coatings were deposited on carbon/carbon（C/C） composites using electrochemical deposition technique. The effects of electrolyte concentration and constant current density on morphology, structure and composition of the coating were systematically investigated using scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transformed infrared (FTIR) spectroscopy. The results show that, the coating weight elevated gradually with the increase of electrolyte concentration, and the morphology of coatings changed from spherical particles to nanolamellar crystals with interlocking structure initially. Then the coating transformed into seaweed-like and nano/micro-sized crystals along the depth direction of the coating. The coatings showed seaweed-like morphology as the deposition current density was less than 20mA. With the less current density, the coating became more homogenous. However, the coating was fiakiness crysal, with needlike crystal stacked upside as the current density reached to 20mA/cm2. The coating weight was improved gradually when the current density increased from 2.5mA/cm2 to 10mA/cm2, then reduced with the increasing current density in the range of 10 to 20mA/cm2.

Surface modification of kaolin, which included coupling agent, calcination, acid modification and alkali activation, mechanochemical activation and intercalation etc, is reviewed. The modification mechanisms and modification methods of kaolinite are discussed. The application of kaolin in ceramics, paints, plastics and rubber etc are also analyzed. Afterwards, the prospect of future researches on modification of kaolin is taken. Surface modification of kaolin denotes use physical, chemical methods and mechanical method, which changes surface properties of kaolinite (surface functional groups, crystal structure and surface adsorption and surface electrical) to satisfy the requirements of the industrial application. Surface properties of kaolinite are controlled by the position of Si-O bonding and Al-(O, OH) groups. Any physical or chemical processing methods which may change Si-O and Al-(O, OH) bonding forms of kaolinite surface could complete the surface modification of kaolin. The surface modification of includes coupling agent, calcination, acid modification and alkali activation, mechanochemical activation, intercalation and so on.

There are lots of methods of evaluating the environmental quality of groundwater. Based on a comprehensive analysis of those common methods, this paper puts forward a method named fuzzy comprehensive evaluation method on water environmental quality based on entropy weight with consideration of toxicology of evaluation factors. Developed from the entropy-based fuzzy comprehensive evaluation method, this method takes into account the influences caused by the toxicology weight and over standard weight of evaluation factors on the calculation of entropy weight. Through some water samples, the evaluation result of this method is more reasonable, objective and comprehensive than the one which is concluded from the entropy-based fuzzy comprehensive evaluation method.

Flow control devices (weir and dam) in a continuous casting tundish are very important to the flow field, which influences the temperature uniform and the inclusion floating. In this work, the weir and dam were firstly optimized through numerical simulation and water simulation synthetically by orthogonal optimization tests. And the optimal parameters showed that the distance from upper weir to inlet was 1000 mm, the distance of upper weir to tundish bottom was 150 mm, the distance from upper weir to dam was 600 mm, and the height of the dam was 320 mm. Then the effect of different arrangement holes on the dam was discussed through RTD curve and velocity field under the optimum flow control device. And it revealed that the hole influenced the flow pattern in that area obviously, a dam with two holes could get a better flow field.

In order to investigate the biotribology behavior of a novel artificial joint pair composed of a carbon/carbon composite femoral head and an ultra-high molecular weight polyethylene (UHMWPE) acetabular cup, a hip joint simulator was employed to predict the clinical wear behavior with a constant load and a lubricant of newborn calf serum. The worn surface and the wear particles generated were analyzed by scanning electron microscopy and laser particle size analyzer. The results showed that the worn surface of UHMWPE had a ripple-like morphology with plentiful furrows. The wear particles generated had various morphologies with a size concentrated at about 15 μm.

Submerged entry nozzle (SEN) bottom structure plays an important role in determining the flow pattern in continuous casting process. This work applies a water model to evaluate the pointed-bottom, flat-bottom and recessed-bottom nozzle performance in ultra-thick slab mold. The jet properties and surface flow are compared for the three kinds of nozzles quantitatively. The results show that flat-bottom and recessed-bottom nozzles are similar in flow pattern, but the pointed-bottom nozzle has smaller jet angle, thinner flow pattern, larger surface asymmetry rate, and higher surface flow intensity.

In order to improve the biocompatibility of carbon/carbon(C/C) composites used for hip prosthesis, pyrolytic carbon coating was prepared on their surface by chemical vapor deposition. The microstructures of the samples were analyzed by scanning electron microscopy (SEM) and the biomedical response was assessed by the morphology and proliferation of MG63 osteoblast-like cells. The results show that the texture on the surface of C/C composites changes from chaotic structure to uniform state after the pyrolytic carbon coating is prepared. Osteoblasts cultured on pyrolytic carbon coating present flat shape with thin thickness, and display better proliferation in comparison with those on the uncoated C/C composites surface.