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The atom transfer radical polymerization is successful for synthesizing the topological type PMMA with α-D-glucose/2-bromoisobutyryl bromide as initiating system, CuBr as catalyzer and PMDETA as ligand. PMMA synthesized by such method has a controllable relative molecular mass and structure. The narrow distribution of relative molecular mass really achieves the controllable activity of ATRP.

Ultrasonic inspection is the most successful non-destructive testing technique for detection of flaws in engineering materials. Generally, discrete wavelet transform (DWT) is widely used to extract features for ultrasonic flaw signal. Directly taking the DWT coefficients as input vectors for training classifier, however, may result in computation complexity or even poor classification performanc. We propose a weighted linear discriminant analysis (WLDA) method to address the problem. In this study, DWT is first applied for the time-frequency analysis of ultrasonic flaw signals, and the wavelet coefficients are extracted as the initial features. After that, the proposed WLDA, which can effectively estimate the within-class and the between-class scatter through calculating similarity based weighting function, is used to reduce the dimension of original features. Finally, the features in new lower dimensional space are taken for flaw classification. Experimental results show that compared with the original and state of art linear discriminant analysis methods, WLDA is helpful for improving classification performance.

Due to the large number of distributed power supply random connected to power grid, it has severely influenced on power quality of the grid. In the storage battery directly on the basis of the DC bus, adopting the method of hybrid energy storage system makes a research on the output characteristics of photovoltaic array and the charging and discharging of battery and super capacitor. Research results show that the hybrid energy storage system can take advantage of the DC/DC converter to coordinate photovoltaic array, energy storage unit and the energy flows among load, also that the stability of DC bus voltage can be ensured by the system switch from the different work patterns.

Power network planning is a NP hard problem difficult to be solved. It can be contributed to similar TSP problem. Aiming at the slow convergence speed of the traditional immune clonal selection algorithm (ICA), adaptive immune clonal selection algorithm without memory（AICA）and adaptive immune clonal selection algorithm with memory(AICAM) are proposed respectively based on the combination of adaptive algorithm of clonal probability, immune probability , and group disaster algorithm. The two proposed algorithms have been applied to Power network planning problem. The adaptive algorithm has strong global search ability and weak local search ability at early evolution. Global search ability is weakened and local search ability is enhanced with the process of evolution in order to find global optimal point. The application of group disaster algorithm can enhance the diversity of the population and avoid the premature problems to some extent. Simulation results indicate that compared with the traditional immune clonal selection algorithm(ICA), the proposed algorithms can enhance the diversity of the population, avoid the premature problems, and can accelerate convergence speed in some extent.

Forging processes, such as liquid forging, rheoforging and thixoforging process, were used in this study as an effective method for manufacturing high-strength, finely-dispersed and highly-uniform AZ91D alloy parts. It has been found that although the microstructures of the three forging parts are all composed of α-Mg and β-Mg₁₇Al₁₂ phases, their shapes, sizes, numbers and distributions are all different, which also influences their mechanical properties. The tensile fracture morphologies were observed and their energy spectrums were analyzed by scanning electron microscopy. The results show that the cracks are mainly originated from the brittle fracture of the β-Mg₁₇Al₁₂ eutectic phases, whereas their fracture morphologies are greatly different, which indicate the direction for providing a reasonable forging process.

The study investigated the effects of mechanical stirring before solidification on the metallurgical structure of hypoeutectic aluminum-silicon A356. A series of stirring trials were conducted in the present study. Emphasis were placed on the morphological changes of the primary phase, which was subjected to different levels of stirring at various values of the rod material and its diameter, insertion temperature and rotation speed. It was found that when the rod was made of the same material as the molten metal, it acted as a nucleation site to generate numerous nucleated primary crystals, which separated from the rod surface continuously into the molten metal with the rotation of the stirring rod, resulting in the refinement and spheroidization of the primary crystals. The ideal semisolid slurry with homogeneous spherical and fine primary crystals could be obtained by optimizing rod insertion temperature, rotation speed and its diameter, which is a key factor in semi-solid forming.

The process of TiCl₄ treatment on the FTO substrate of DSSC were analyzed and the microstructures of substrates before and after treatment were observed. Further more, the influence of TiCl₄ treatment on the substrate of Dye-sensitized solar cell to photo-current voltage performance was numerical analyzed.

Northern Songliao Basin contains a large amount of oil shale resources. Due to the limitation of the oil and gas enrichment area, movable oil and gas and mining conditions, must determine the advantageous area of movable resource. Based on the improved Δ logR model, evaluated the organic matter abundance and residual hydrocarbon content; Based on the least squares method, established a model between clay mineral and well logging curve and calculated clay mineral content; Combined with organic carbon and residual hydrocarbon, evaluated movable oil amount. The evaluation results show that Qn1 Member favorable area mainly concentrated in the central and northern part of Qijia-Gulong depression and the middle part of Longhu Pond-Daan terrace; Qn23 Member favorable area mainly concentrated in Longhu Pond-Daan terraces middle part and southern and middle part of Qijia-Gulong depression. Qn1 Member movable oil resource is 150 million tons, Qn23 Member movable oil resource volume is 350 million tons, total movable oil resource of Qingshankou Formation is about 500 million tons.

More internal transistor of GPU is used as a data processing rather than process control. Compared with the existing multinuclear CPU, it has more processors and higher ability of the whole parallel processing, which is suitable for a large scale super calculation based on desktop platform. CUDA platform, put forward by NVIDIA Company, which is a new hardware and software architecture of realized the general calculation of GPU combined with the high parallel ability, and adopt CUDAC programming language to realize a parallel binary image connected domain label algorithm based on CUDA. The algorithm uses eight connection body labels, which has the high parallel ability, the less association between steps and the efficiency of the great promotion space.

Use concrete pressure testing machine to test the properties of Cement slurry , and conduct the ASTMC1202 penetration test of the properties and MIP which test the properties and microstructure characteristics. Base on the analysis of the relationship of cement strength and permeability, microstructural features. The results show that, with the increase of the permeability of cement slurry net of intensity decreased by 13%; The increase of pore volume total 11%, and the average pore volume rose 5%, cause pore internal loose, strength fell 0.74%; Cement of a few aperture increase to 7 nm, can lead to internal form lots of pore channels, intensity decreased. when the most several aperture is more than 10 nm, cement strength average less than 41.4 Mpa; Age can effectively passivation cement phase crystallization geometrical shape, and effective crystallization refined grain size.