Fe3O4 nanoparticles were modified with ionic surfactant (CH3O)3Si(CH2)3N+(CH3)(C10H20)2Cl−, and then the chloridion was replaced by the anion C9H19C6H4(OCH2CH2)20O(CH2)3SO−3 through an ion-exchange process. As a result, an electrical double–layer structure was formed on the surface of Fe3O4 nanoparticles. The results showed that the surface layer has been successfully grafted on Fe3O4 nanoparticles surface and the modified Fe3O4 nanoparticles were well dispersed. The loss shear modulus G'' of Fe3O4 nanofluids was significantly greater than the storage shear modulus G' at room temperature, which confirms the typical fluid-behavior. Great stability and good flowability are well maintained after standing for a year at room temperature.

The adsorption characteristics of EDTA on α–hemihydrate desulfurization gypsum surface and its influence on crystalline habit and crystal morphology were studied by use of SEM, MICRO-FTIR, UV adsorption spectrophotometer and XPS technique. Its crystal modifying mechanism was also analyzed from the viewpoint of crystal growth. The results show that the adsorption of EDTA on α–hemihydrate desulfurization gypsum is chemical adsorption. The adsorption isotherms curve basically follows Langmuir equation, its max adsorption amount is 15.2mg and the thickness of adsorption layer 6.5 nm. The addition of EDTA evidently changes the crystalline habit and crystal morphology of α–hemihydrate desulfurization gypsum, and the growth in the C axis direction is inhibited, leading to large crystal size and  transformation of crystal shape from long clavate-like to short prismatic or lamellar -shaped. The crystal modifying effect of EDTA is susceptive to pH values, and the optimum pH condition in liquid phase is neutral. EDTA is selectively chemisorbed on the (111) face of gypsum crystal by complex reaction between hydroxyl and
Ca2+, which inhibits the growth of c axis and weackens the relative advantage of the growth rate of in different c–axis directions, consequently leading to the transformation of crystalline habit and crystal morphology of dihydrate gypsum.

The Ti(C,N) cermet and 17–4PH precipitation–hardened stainless steel were brazed in vacuum using nickel–based eutectic filler BNi–7. The effects of brazing temperature and brazing seam thickness on the microstructure and shear strength of the brazed joints were investigated. BNi–7 filler had a strong dissolution ability to the binder of the Ti(C,N) cermet. This is beneficial to the wide distribution of melting point depressant (phosphorous) in the Ti(C,N) cermet side and producing a good interfacial bonding. The distribution zone of phosphorous in the Ti(C,N) cermet side that is adjacent to the brazing seam increased as the brazing temperature rose. A maximum shear strength of 454 MPa was achieved at a brazing temperature of 1100 ^oC and a brazing time of 60 min with a brazing seam thickness of 50μm.

Pt, Pt–Fe, Pt–Co, and Pt–Ni nanoparticles were synthesized on single–walled carbon nanotubes (SWCNT), and their effects on electrocatalytic activity for methanol and ethanol oxidations were investigated using cyclic voltammetry and electrochemical impedance spectroscopy. Followed by the order of Pt–Fe/SWCNT, Pt–Co/SWCNT and Pt–Ni/SWCNT, the catalysts demonstrate better electrocatalytic activities for both methanol and ethanol oxidations, but less tolerance to CO poisoning. In comparison to Pt/SWCNT, Pt–Ni/SWCNT exhibits better catalytic characteristics for methanol oxidation, and Pt–Ni/SWCNT could be a desirable catalyst candidate for direct methanol fuel cells. However, for ethanol oxidation, Pt/SWCNT has better catalytic characteristics than Pt–Ni/SWCNT.

Based on the Density Functional Theory (DFT), the ring-opening mechanisms of monocyclic segment of furfuryl-alcohol resin were investigated by QST2 (Quadratic Synchronous Transit) and IRC (Intrinsic Reaction Coordinate) methods. Gaussian 03 software package was employed in this study. In order to investigate the influence of water on the ring-opening, the reactions were respectively analyzed with the participation and absence of water. The ring-opening mechanisms were discussed according to the analysis of Mulliken charges as well as the energies calculated at B3LYP/6–31G** and QCISD/6–31G** levels. Results showed that water molecules exhibit importance influence on the ring-opening process. For the reaction with the participation of water, hydrogen bonding will be formed between the oxygen atom on the furan ring and the water molecule. Because of the influence of water, the conjugation of C–O bond was weakened, and gradually resulting in the ring-opening of furan ring. Though such path, only one transition state was experienced and a chain-type saturated ketone structure was finally obtained. According to the distance between oxygen atom on the furan ring and the allyl hydrogen atom on the adjacent aliphatic hydrocarbon, there were two ring-opening paths without the attendance of water. (1) If the hydrogen atom is close to the oxygen atom, the allyl hydrogen radical will bond with the oxygen atom firstly, results in the obtaining of an intermediate that is characterized by enol as well as diene structures. Subsequently, the hydrogen atom on the hydroxyl group will migrate again, and leading to the formation of a chain-type unsaturated ketone. (2) If the hydrogen atom is far from the oxygen atom, the allyl hydrogen radical migrates to the adjacent carbon directly. The data of activity energies indicated that the incorporation of water benefits in the ring-opening reaction. For the reaction with the participation of water, the activity energies calculated at B3LYP and QCISD levels were 299.29 kJ/mol and 343.25 kJ/mol, respectively. In contrast, without attendance of water, the activity energies of route 1 were 312.3 kJ/mol and 353.11 kJ/mol, while whose of route 2 were 354.24 kJ/mol and 378.82 kJ/mol. Therefore, the decrease of water benefits in the retarding of ring-opening degradation reaction.

High temperature compression tests were performed on 22Cr–5Ni–3Mo–N high alloy steel cast slab in the temperature range of 900–1200 ! and the strain rate range of 0.1–50 s−1 by Gleeble–3800 thermomechanical simulator machine. The regulations of true stress–true strain cures were analyzed at different working conditions. Based on the experimental data, the hyperbolic sine, the exponential and the power constitutive models were established describing the high temperature flow peak stress of the steel. The peak stresses were predicted by the constitutive equations under the corresponding experimental conditions. The accuracy and reliability of the equations were evaluated. The results show that when the peak stress is predicted by the hyperbolic sine model, the consistency between the experimental and
calculation values is the best. The correlation coefficient (R) is 0.998, and the average value of relatively errors is 4.9%. These will provide a basis of theory for selecting plastic deformation constitutive model of the steel at high temperature.

The Na–β''–Al2O3 electrolyte materials with the relative density of 98% were synthesized by a solid state reaction route employing boehmiteNa2CO3MgO as starting materials and TiO2 as additive and characterized by X-ray diffraction, SEM, bending strength testing and AC 4-probe method. The results show that TiO2 can promote the sintering performance of Na–β''–Al2O3 electrolyte effectively and the purities of β phases were all above 96% when the content of TiO2 ranging from 0.5%–2%. The obtained samples with TiO2 dopants comprised of compact and plump grains exhibiting high density with uniform microstructure. The bending strength of the specimen was enhanced obviously with the increase of the TiO2 additives. The ionic conductivity increased compared with the plain sample due to the decreased boundary resistance of the material.

Using “3D–pinpointing approach”, Zr55Ti2Co28Al15 alloy with high glass–forming ability (GFA) is discovered in quaternary Zr–Ti–Co–Al system, whose critical diameter for BMG formation reaches 8 mm. In comparison with Ti–free ternary Zr56Co28Al16 BMG, glass transition temperature (Tg) of Zr55Ti2Co28Al15 BMG decreases by about 9 K. Nevertheless, no significant difference is observed in the elastic constants such as Young’s modulus, shear modulus, bulk modulus and Poisson’s ratio. Compressive fracture strength of Zr55Ti2Co28Al15 BMG is around 1990 MPa, while its fracture strength in tension is about 1690 MPa.

The W–type ferrites, BaMe2 Fe16O27, were prepared by sol–gel method. The performances of the ferrites were improved by changing the Me2(Co2, CoNi, CoZn). The structures, morphologies, magnetic properties and microwave absorption properties of the samples were characterized by X-ray diffractometer (XRD), scanning electron microscope (SEM), vibrating sample magnetometer (VSM) and Vector network analyzer. According the SEM observations, it is found that all the ferrites showed a hexagonal platelet–like shape. The XRD results indicated that all the samples were W-type ferrite. The synthesized samples exhibited paramagnetism and strong magnetism. Besides, the composite, which was blend with paraffin BaCoZnFe16O27/paraffin, has a better microwave absorbing property than the other
ferrites. Moreover, the reflection loss of one–layer absorber with the BaCoZnFe16O27 sample was calculated. The band width (with respect to −10 dB reflection loss) is 5.42 GHz at a matching thickness of 3.50 mm and the maximal reflection loss is −16.23 dB.

The electron transport and back-reaction in DSCs with and without TBP were investigated by intensity-modulated photocurrent spectroscopy (IMPS) and intensity-modulated photovoltage spectroscopy (IMVS). The results indicate that the increase of the open-circuit voltage was attributed to the negative shift of the TiO2 conduction band potential by the surface adsorption of TBP. The negative shift of the TiO2 conduction band potential reduced the electron injection force and decreased the photoaccumulated charge concentration in the TiO2 film, which increased the electron transit time (τd) and decreased the short-circuit current. Overall, the addition of TBP into the electrolyte increased the efficiency of DSCs by 37%.

A grain growth simulation model for ceramic material sintering process with sintering additives based on cellular automata is constructed based on the grain growth driving force theory of grain boundary energy and the curvature of the grain boundary. The results show that the sintering additives on the grain boundarles have a strong pinning effect. The grain growth index of the ceramic material with sintering additives is lower than that without sintering additives. Add sintering additives can effectively refine the grains The simulation results are in good agreement with the microstructure of Al2O3/TiN ceramic materials with sintering additives. Cellular automata model is applicable to the grain growth simulation of the ceramic material with sintering additives in sintering process.

Finite element simulation was carried out for analyzing the accumulative rate of equivalent strain and final equivalent strain of 5052 aluminum alloy processed by constrained groove pressing (CGP) and unconstrained groove pressing (UGP). In addition, experiments were conducted for investigation of grain refinement as a function of accumulative rate of equivalent strain as well as final equivalent strain. The results show that CGP has a higher accumulative rate of equivalent strain and final equivalent strain than UGP. Compared with UGP, CGP is more beneficial to grain refinement due to the higher accumulative rate of equivalent strain and final equivalent strain, which is determined by two different mold constructions and independent of the material and processed condition.

TiN/TiAlN multilayer coatings were prepared by arc ion plating with different pulsed bias voltages. With the increase of pulsed bias voltage, the amounts of the macroparticles were largely reduced. The increase of the pulsed bias voltage caused the decrease of Al/Ti atom ratio. The multilayer coatings exhibited growth in preferred orientation of (111) plane with the grain size ranging from 8nm to 14nm. The hardness of TiN/TiAlN multilayer coatings was over 36GPa, which was 3.9 times that of M2 high speed substrate. All the adhesion strength of TiN/TiAlN multilayer coatings was more than 60 N. All the TiN/TiAlN multilayer coatings showed better wear resistance.

Accumulative roll-bonding (ARB) was applied to AZ31 magnesium alloy at various rolling temperatures and cycles. The microstructures and mechanical properties of ARBed AZ31 alloys were investigated. The results show that the grain sizes decrease with decreasing of the rolling temperatures and increasing of ARB cycles. The grain refining is prominent until three cycles and the microstructures become more homogeneous with increasing of ARB cycles. The changes in tensile strength and ductility are more complicated as a result of the combined effects of the temperature and accumulated strain on grain size, texture and interface bonding. The best compromise between the strength and ductility is obtained after ARB at 350  for three cycles. The average ultimate tensile strength is 277 MPa and average tensile elongation is 20.6% which can be further improved after annealing.

Corrosion–resistant performance of Nickel-based alloys with different Cr contents in Cl−ions solution was studied by using electrochemical techniques. The results showed that the resistant of the electrochemical corrosion was improved with the increasing of Cr contents in the Nickel–based alloy. The concentration of the Cl−ion solution had greatly influence on the corrosion resistance of Ni–9Cr, Ni–15Cr and Ni–20Cr alloys. Especially, the corrosion resistance of Ni–9Cr alloy was the most serious in 0.6mol/L NaCl solution. The passive film on the surface of the Nickel-based alloys in 0.6mol/L NaCl solution was analyzed by using the XPS testing technology. It was found that the proportion of Cr–oxide and hydrogen that formed on passive film surface of Ni–30Cr alloy were 4.840 and 4.130 mass percent, respectively, exceeding the other Ni–Cr alloys. Meanwhile, the mechanism of the pitting corrosion for Ni–Cr alloy in the different concentration of NaCl solution was discussed.

Total reflection–Fourier transform infrared spectroscopy (FTIR–ATR), Differential scanning calorimeter (DSC) and Thermal weight loss (TG) were used to study the composition and thermal properties of four different types of recycled plastics, and the component distribution was also analyzed by the infrared image system. The results showed that the main components in 3 types of plastics were polypropylene (PP), and the other one was composed of a blend system of high density polyethylene (HDPE) and PP. The blend system of HDPE and PP was simulated, the fitting curves related for different PP contents in the recycled plastic were built, and finally the PP content in the recycled plastic was correctly determined.

The advanced electron backscatter diffraction (EBSD) technique is used to study the orientation distribution function (ODF), the content of texture components and the intensity of the γ fiber of the interstitial-free steels annealed samples (after cold rolling). It is found that the existence of P may block the dislocation movement and the grain boundary migration leading to the grains to have the same orientation and the sharpe {111} plane texture. The adding of Ti results in the intensity of {554}<225> texture component in the cold-rolled samples, which is inherited to be the recrystallized texture. The misorientation between {554}<225> and {111}<112> texture components is only 6o. Therefore, the high quantity of {111}<112> is found in the high strength Ti-IF steels. Mechanism of effects of P and Ti on
the {111} plane texture is also discussed.

Catalytic graphitization of polyarylacetylene resin was studied with the assistance of different kinds of catalysts. The effects of Fe2O3 and carbonized temperature on PAA graphitization were investigated The structure and morphology of PAA resin and graphitized products were characterized by XRD, Raman, SEM and HRTEM. The results show that Fe2O3 was reduced to iron during calcining, which accelerated the graphitization of polyarylacetylene resin. The graphitic structure was formed with the increases of both Fe2O3amount and heat treated temperature, and the degree of graphitization was 92.3%. The graphitized product was composed of the graphitic carbon, the iron nanoparticles and the amorphous carbon. The iron nanoparticles were encapsulated by the graphitic layers. The graphitized nano-ribbon extended throughout the amorphous carbon matrix and interconnected each other to form a graphitized nano-ribbon network.

Based on the same crystal structure and atomic structure of Cu and Co, coprecipitation method was taken to fabricate the ultrafine cemented carbide with Cu partly instead of Co. The effect of Cu on the properties of WC–10Co cemented carbide was investigated. The results show that with the addition of Cu by coprecipitation method, the Co(Cu) solid solution forms, and since Cu can distribute uniformly in WC–10Co during sintering,, the solubility of WC in binding phase decreases, the re–precipitation of dissolved WC particles can be hindered effectively, which results in the repression of WC grains growth, and the hardness of cemented carbide increases. The addition of element Cu can also play a role in solid solution strengthening of binding phase improving the transverse rupture strength of cemented carbide. When the Cu content is 1.5 wt%, cemented carbide can obtain the best mechanical properties with the hardness increasing from HRA92.6 to HRA 93.2 and the transverse rupture strength increasing from 2490 MPa to 2150 MPa.