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According to the mechanism of thermal insulation, closed pore perlite, hollow glass microsphere and nanoantimony tin oxide (ATO) powder three different kinds of functional fillers were adopted respectively to prepare obstructive, reflective and radiative thermal insulation coating base on polyvinylidene fluoride emulsion, and how the category and content of functional fillers effect the thermal insulation performance of the fluorocarbon thermal insulation coating (FTIC) was investigate. The test results showed that, all the three functional fillers has an significant effect on the thermal insulation performance of FTIC.

TiO2 nanorod array films with or without Nb doping grown directly on transparent conductive glass (FTO) were prepared by a facile hydrothermal method. The films were characterized by means of field emission scanning electron microscopy (FE-SEM) with energy-dispersive x-ray spectra (EDS), X-ray diffraction (XRD) and the X-ray photoelectron spectroscoy (XPS). The electrochemical impedance spectroscopy (EIS), linear sweep voltammetry (LSV) and transient photocurrent were investigated in a three-electrode system with TiO2 nanorod array film served as the photoanode. The photoelectrocatalytic activity of the films was evaluated by the oxidation of glucose under UV irradiation. The results show that both the pure and Nb-doped TiO2 nanorods perpendicularly grown on FTO substrate are rutile phase. The resistance of the TiO2 nanorod array photoanode is decreased significantly by Nb doping. The steady-state photocurrent (iss) for glucose oxidation at Nb-doped TiO2 nanorod array film is much higher than that at the pure one. The enhanced photoelectrocatalytic activity of the Nb-doped TiO2 nanorods could be attributed to the enhanced charge transport ability.

Based on the instance of extremely thick coal seam mining under aquifer in Gonggeyingzi Coal Mine, the theoretical calculation for the height of water flowing fracture zone in this coal mine was 30.6m and calculation model was established. Analyzed by the UDEC software, the surface displacement of backfill mining was 1532mm and the height of overburden rock plastic zone was 36.5m. Compared with 135m away from coal roof to aquifer, slicing backfill mining under aquifer was confirmed to be safe and feasible based on the theoretical calculation and analysis of UDEC. The results provided the basis for the safety of extremely thick coal seam mining under aquifer in this coal mine.

In the view of the complex influence factor, simplified research method and structural or partial structural application model a drilling parameter selection optimization method based on case-based reasoning is provided in this paper. The goal of the research is to build up a drilling parameter selection optimization method which has great applicability. Based on the field drilling data and parameters a case base is built up. Afterward data discovery is used to deal with the case selection problem and select case from case base. Combining with field situation, drilling parameters selection is optimized and drilling speed could be predicted.

The polycrystalline La0.62Sb0.38MnO3 sample has been prepared by the solid-state reaction method. Structural, magnetic and electrical transport properties have been researched. X-ray diffraction analysis confirms the hexagonal crystal symmetry. Magnetization measurements indicate La0.62Sb0.38MnO3 experienced from paramagnetic to ferromagnetic state transition with decreasing temperature at about 225 K. Resistivity dependences on temperature exhibit metal-insulator transition (MIT), and the maximum magnetoresistance (MR) ratio is about 33 % at temperature of 189 K and magnetic field of 2 T.

A method of low cost strapdown inertial Attitude and Heading Reference System based on MEMS is implemented in this paper. Based on the analysis of the modules, the proper selection of the core processor and the inertial devices, the hardware components of the system is presented; Using the gradient-descent algorithm which is based on quaternion, it can finish the calculation of the attitude; This AHRS can realize the real-time extraction, calculation and the output of the information. Keywords-MEMS; AHRS; Gradient-descent algorithm

The transport properties of polycrystalline La0.9Sb0.1MnO3(LSMO) bulk prepared by the solid-state reaction were investigated. We find that transport behaviors heavily depend on the synthesis process. The resistivity of LSMO1 for less rubbing time shows one metal-insulator transition (MIT) peak at temperature of 201 K, while the resistivity of LSMO2 for more rubbing time shows a MIT and a shoulder at about 240 and 140 K, respectively. The magnetoresistance (MR) ratio of LSMO2 reaches 41% under magnetic field of 2 T. Moreover, the MR ratio keeps significant value within broad temperature range. The infrared (IR) absorption spectra of LSMO2 show that the stretch-mode peak split into two Gaussian peaks with the gap about 70 cm-1. This large splitting indicates there are strong distortion and disorder in LSMO2 sample. The results are interpreted in terms of the disorder system and phase separation in perovskite manganites.

nanohydroxyapatite (nHA) and collagen were utilized to fabricate the bio-inspired organic-inorganic composite coating (OICC) via the Drop-on-Demand (DoD) micro-dispensing technique, which could flexibly construct multi-layer structures with varied materials composition within a layer and /or among layers reliably. This technique has been further investigated on its capability of OICC fabrication with regards to various materials (hydroxyapatite and collagen) as well as its dispensing parameters. A four-layered structure was formed, with the sequence of nHA-collagen-nHA-collagen from bottom to top. The dispensing parameters were also investigated with regards to the characteristics of the OICC fabrication. The coating was then subjected to various characterizations including scanning electron microscopy (SEM), X-ray diffraction (XRD), energy dispersive X-ray spectroscopy (EDS) and adhesion test. SEM and XRD results revealed that the DoD micro-dispensing technique did not change the morphology and phase of these two coating materials. And the results of EDS further demonstrated the corresponding elemental distributions within the four-layered coating structure which demonstrated the feasibility of the DoD micro-dispensing technique for the fabrication of thin-layered OICC.

Oil field exploitations have a considerable impact on environmental security. The method of oil field environmental security evaluation method should be introduced into oil field exploitations for protection of environmental security. The frame model of pressure-state-response (P-S-R) was selected for oil field environmental security evaluation. Assessment levels were classified into five levels according to the value of synthetical index (SI), which was determined by the calculation of information entropies and value assignment of analytic hierarchy process. Finally, quantitative assessments of oil field environmental security situation were presented.

Oil field exploitations effected the environmental security, so the mehtod of oil field environmental security early warning should be introduced into oil field environmental management. The grey forecasting model was selected to predict individual index of environmental security early warning for oil field. Based on the individual index prediction, the method of environmental security early warning (synthetical early warning) was presented. Finally, according to the analysis of the results of oil field environmental security early warning, the regulation direction of oil field environmental security was proposed.

With the generalized displacement parameters of spline knots chosen as basic unknowns, the node displacement functions of spatial mega frames were built up, then element node displacements could be expressed by these parameters. New stiffness equation of spatial mega frame was deduced according to energy variational principle. The nodal displacement and nodal forces were worked out by the displacement parameters of spline knots. Process of block assembling for spline-discretization matrix was introduced briefly. One spatial mega frame was calculated by QR method and different finite element softwares. Comparation among the results and those of references proves that QR method is exactly an economical, effective and reliable method for computation of spatial mega frames. It provides a new approach for simplified calculation to spatial mega structures, so has good theoretical and practical value.

The overlay algorithm is an important branch in computational geometry field, it is an important process for computing exact Minkowski sum of two convex polyhedrons. By improving the existing plane sweep algorithm, the overlay algorithm for simple subdivision of arbitrary polygon in plane is given. The algorithm can be used to overlay arbitrary polygon after subdivision into simple polygon in the plane. It has lower time complexity than the existing overlay algorithm. The whole algorithm consists of three steps: line segment intersection, reconstructing topology and constructing the DCEL for overlay graph. The results show that the algorithm can compute the overlay of two planar subdivisions in linear time.