Search

Recently, the position of shale gas is more and more important in the world energy structure. The lithology of Xiamaling Formation in Beijing area mainly include siltstone, silty shale and shale. The organic carbon content is relatively high, averaging 2.28%. The kerogen type of organic matter is dominated by II1 and II2 types, and thermal evolution level is relatively high, averaging 2.05%. Intergranular micropore is well developed, and most of the micropore diameter is 1-7µm, so the reservoir condition is good. The content of the brittle mineral is relatively high, so it can be easily fractured in production. The content of the clay mineral is relatively high, so it has a good adsorption capacity. Through wild prospecting and geochemical analysis for samples, this paper systematically assesses the Xiamaling Formation shale in Beijing area, which can provide basic stata for further shale gas study in Beijing area.

In traditional geological field practice (GFP), there are many problems, such as waste of human and material resources, dispersion of geological phenomenon and failure to reproduce geological processes, which lead to the inefficiency of traditional education. Recently, virtual geographic environment (VGE) has become increasingly popular. It can provide us an immersive, interactive and collaborative three-dimensional (3D) multi-user virtual environment which can help us to solve the above problems. In this paper, we present a Virtual Geological Field Practice System (VGFPS) for Huyu Region based on OpenSimulator, an open source virtual world server which can be used to create VGEs. VGFPS integrates texts, images, videos and other multimedia with digital elevation models (DEMs), remote sensing (RS) images, buildings and landscapes, geological process simulation models and in-world scripts to enable teachers and students to explore, navigate, interact in virtual environment and communicate, collaborate with each other. Practices show it’s feasible to use VGEs to make GFP education more effective and it can be applied to the domain of virtual education.

With the fast development of data acquisition and web transmission, the age of big geospatial data(BGD) has come. BGD will greatly change peoples’ life-style of and our society’s work mode. In agriculture field, there will also be a lot of changes brought by BGD in future. In this paper, we had a study on the processing of BGD and its application in agriculture. Firstly, we introduced BGD including its definition, value and application areas. Secondly, we summarized the research progress and key technologies of BGD processing in the cloud computing environment. Lastly, we talked about the application of BGD in agriculture industry and looked forward to its development trend.

Factors of affecting BER are determined by its architecture in OCDMA system, the loss of optical devices, encoder / decoder structure, optical fiber transmission channel and so on. Taken together, the main factors are light source chirp, noise, group velocity dispersion, fiber channel attenuation and loss of optical devices. The impact on system BER performance is analyzed in this paper.

A new method, which combines the measurement and the estimation of the radiated noise variation, is proposed in this paper to predict the real-time radiated sound pressure. The estimation errors of the pressure variation are calculated and compared with the pressure estimation errors, using the Boundary Element Method(BEM). The comparison results show that the errors of the pressure variation estimation method are smaller than direct sound pressure estimation at the eigenfrequencies and most frequencies. The method can be used to decrease the real-teime radiated sound pressure estimation error.

An amphiphilic graft copolymer with poly(acrylamide-methacrylate) as a main chain and octylphenyl polyoxyethylene as side chains (P(AM-MA)-g-C8PhEO10) was successfully synthesized via free radical copolymerization. The structure and the composition of the graft copolymer were characterized by FTIR, 1H-NMR and elemental analysis (EA) in detail. The absolute molecular weight of the copolymer is 1.304×106, as determined by static light scattering (SLS). The molar ratio of acrylamide monomer to the macromonomer is 33:1 in the copolymer and 53 C8PhEO10 branch chains attach to a P(AM-MA) backbone. The micellar behavior of P(AM-MA)-g-C8PhEO10 was preliminarily studied by means of surface tension measurements, transmission electron microscope (TEM) in aqueous solution. It was found that the stable spherical micelles with core-shell structure are formed and polymolecular micelles are larger and more compact than monomolecular micelles. In addition, the graft copolymer has favorable thermal stability.