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ATRP is one of the most active fields in polymer science. The feature of ATRP is chain propagation by way of transfer of halide atom with or without the catalysis of transition mental compounds. The termination reaction between radicals is reduced by low concentration of free radicals under the control of the fast transfer. A variety of monomers including styrene, acrylates, methacrylates, and dienes can be used in this technique. ATRP is a simple and inexpensive process for controlled "living" radical polymerization leading to well-defined homopolymers and copolymers. In this paper, the mechanism, initiator, catalyst systems, polymerization mediums and conditions of ATRP are introduced, the prospect of ATRP is also discussed.

T2 red copper plate and DT4C electrical pure iron plate were cladded by explosive welding. Microcosmic analysis and bonding strength of the bonding interface were also studied. Results indicate that the welded zone appears periodical wavy metallurgical interface and obvious element diffusion occurs in the interfacial zone. In addition, no separation happens after the bonding strength test and tension-shear test and the broken zone takes place in the T2 red copper part of the samples, indicating that the bonding strength of the welded interface can get no less than the strength of T2 red copper.

Optical metallographic examination, scanning electron microscope as well as energy dispersive X-ray spectrometry was operated to the interface of titanium/steel laminates manufactured by explosive welding. Three types of microcosmic defects as brittle Ti-Fe intermetallic compound, shearing crack, and brittle Ti-Fe-O layer were found at the interface of titanium/steel laminates. The reasons for above three microcosmic defects were analysed.

Optical metallographic examination, scanning electron microscope as well as energy dispersive X-ray spectrometry was operated to the interfaces of titanium/steel laminates manufactured by explosive welding. According to the variation of the thickness of brittle Ti-Fe intermetallic compound at the interfaces, typical wave interfaces of titanium-steel laminates are classified as over melted wave interface, tinyly melted wave interface and optimum wave interface. Furthermore, the features of three wave interfaces are brought forward.

In depositing nitrogen doped tungsten oxide thin films by using reactive dc pulsed magnetron sputtering process, nitrous oxide gas (N2O) was employed instead of nitrogen (N2) as the nitrogen dopant source. The nitrogen doping effect on the structural and optical properties of WO3 thin films was investigated by X-ray diffraction, transmission electron microscopy and UV-Vis spectroscopy. The thickness, refractive index and optical band gap energy of these films have been determined by analyzing the SE spectra using parameterized dispersion model. Morphological images reveal that the films are characterized by a hybrid structure comprising nanoparticles embeded in amorphous matrix and open channels between the agglomerated nanoparticles. Increasing nitrogen doping concentration is found to decrease the optical band gap energy and the refractive index. The reduced band gaps are associated with the N 2p orbital in the N-doped tungsten oxide films.

Through the analysis on the relations of the three main participants of the government, the enterprise and the farmers, the thesis has established the gaming model between the enterprise and the forest farmers and found that only when the additional benefit they each obtain is larger than the construction cost for the development they paid, optimal combination of Nash equilibrium can be accepted by enterprises and forest farmers and Pareto improvement will be possibly formed， the smooth development of energy forest construction can be ensured.

Study the properties of AlSi9Cu3 aluminum alloy test bars fabricated by liquid forging with instruments such as optical microscope, direct reading spectrometer and micro-controlled electronic universal testing machine. Further more，analyze the microstructure and forming mechanism of AlSi9Cu3 aluminum alloy fabricated by liquid forging, the study shows : AlSi9Cu3 aluminum alloy fabricated by liquid forging has excellent performance and good prospects in production.

In this study, some Ni, Bi elements were added into low-Ag (less than 1%) Sn-Ag-Cu (SAC) solder. The effect of these additive elements on the solderability, intermetallic compounds (IMCs), and electromigration performance of low-Ag SAC (LASAC) solder were investigated. With the increase of Bi content in LASAC-0.05Ni-xBi (x=0, 2.0, 2.5, 3.0, 3.5, 4.0) solders, the peak melting point decreases while the wetting area of solder alloy increases. With the addition of Ni, the IMC between Cu pad and LASAC solder transforms from Cu6Sn5 to (Cu1-xNix)6Sn5 and the morphology of the IMC turns from bulk-like to needle-like. Either the addition of Bi or Ni will slow down the IMCs growth rate during high temperature storage aging (HTS) at 180°C and has a positive effect on electromigration performance of LASAC soldering.

Mixed molybdenum-tungsten oxides of varying stoichiometry (MoxW1-xO3, 0 < x