One specie of Pectinidae with a crossed-lamellar structure and one of Plicata with a nacreous structure were selected as the target materials in this paper. The growth of bone-like apatite on the surfaces of these two kinds of microstructures by a pre-treatment and an in vitro bioactivity assessment was investigated. The apatites were deposited more compactly and more quickly on the surface of crossed-lamellar structure in the preliminary stage of immersion in PBS, as well as in SBF. However, these two kinds of microstructures exhibit identically an excellent bioactivity after a subsequently long-term in vitro mineralization process in SBF. Therefore, in contrast to nacreous structure the crossed-lamellar structure can promote the deposition of the apatites no matter in a short term or in a long term.

A temperature-responsive polymer was synthesized by co-polymerization of N-isopropylacrylamide and acryloyloxybenzophenone. Meanwhile, poly(vinyl alcohol) (PVA) was modified by glycidyl methacrylate. Taking the synthesized polymer and the modified PVA as fiber-forming precursor reagents, of which spinning solutions were then prepared, respectively as the raw materials for producing fiber. Finally, the temperature-responsive Janus nanofibers were fabricated by side-by-side electrospinning under UV irradiation. Scanning electron microscope and transmission electron microscope observation results show that the prepared nanofibers have double-faced structure. The results of nuclear magnetic resonance spectroscopy reveal that the applied ultraviolet irradiation facilitates the formation of crosslinking structure for the double-faced nanofibers. The effect of side-by-side electrospinning process conditions on the yield and average diameter of the Janus nanofibers was investigated, it was found that the yield of the Janus nanofibers can exceed 90% when the flow rates of the two spinning solutions are less than 0.3 mL/h and the spinning voltage is lower than 22 kV. In addition, the average diameter of the Janus nanofibers can be adjusted by changing the receiving distance within a certain range. The prepared Janus nanofibers with a water-soluble polymer content (mass fraction) of less than 2% have good stability in water. When the temperature of the aqueous medium increased from 25℃ to 35℃, the prepared Janus nanofibers can transform from a stretching configuration to a curling one, and this temperature-responsiveness is reversible.

An epoxy resin modified thermo-reversible polyurethane with self-healing ability was manufactured successfully by introducing E51 epoxy resin into Diels-Alder reaction-based thermo-reversible polyurethane. The tensile strength, Young's modulus, impact toughness and Shore hardness of the thermo-reversible polyurethane were significantly enhanced, while the elongation at break of which was remained at a relatively high level after epoxy resin was introduced. The 20% epoxy resin-modified thermo-reversible polyurethane material presents high mechanical properties such as strength, toughness and hardness, as well as excellent self-healing characteristic. If damages such as cracks and crevices have been accidently emerged on the epoxy resin modified thermal reversible polyurethane, such damaged spots can be recovered through a post heat treatment by either 130℃×20 min or 60℃×24 h. Moreover, such repair may be allowed to repeat several times for the same location after being subjected to repeatedly damages. It is believed that the enhancement of mechanical performance of the epoxy resin modified thermal reversible polyurethane may be ascribed to the so called "forced mutual dissolution" and "synergistic effect", resulted from the interpenetrating polymer network structure formed through entanglement of the rigid phase of epoxy and the elastic polyurethane phase of polyurethane. Meanwhile, the repeatable self-healing of the epoxy resin modified thermal reversible polyurethane may be due to the synergistic effect of the thermo-reversible Diels-Alder reaction and the thermal movement of molecular chains.

Good corrosion resistance of 2024 Al-alloy without reducing mechanical properties can be obtained by retrogression and re-ageing (RRA) treatment. The effect of retrogression times of 0.1 h, 0.2 h, 0.3 h, 0.4 h and 0.5 h on the microstructure and corrosion resistance of 2024 Al-alloy treated by RRA were investigated by transmission electron microscopy, scanning electron microscopy, hardness tester, intergranular corrosion test and electrochemical corrosion test. The results show that the main precipitation strengthening phase of 2024 Al-alloy by RRA treatment is S phase. When the retrogression treatment time is 0.2 h, the S phase are small and uniformly distributed, and the properties of the alloy were also significantly improved. At this time, the hardness of the alloy is 147.2 HV_0.5, the intergranular corrosion depth is 98.5 μm, the free-corrosion potential is -0.64 V, the free-corrosion current density is 0.24 μA·cm^-2, and the resistance value is 31397 Ω·cm². Therefore, the appropriate retrogression time is beneficial to improve the hardness and corrosion resistance of 2024 aluminum alloy with RRA treatment.

Polybutylene adipate (PBA) protective coating was prepared on fluorinated AZ31 Mg-alloy by uniform speed lifting method and then the coated Mg-alloys were subjected to plasma treatment with different power and time. The effect of plasma treatment on the surface morphology, phase composition and surface wettability of PBA protective coating were characterized by means of scanning electron microscope (SEM), X-ray photoelectron spectroscope (XPS), Fourier transform infrared spectroscope (FT-IR) and contact angle measuring instrument. The corrosion resistance of the coated Mg-alloy was characterized by potentiodynamic polarization curve measurement and electrochemical impedance spectroscope (EIS). The biological activity of the protective coatings was verified by comparing the cells adhesion on the coating surface before and after plasma treatment. Results show that plasma treatment could increase the surface roughness of PBA protective coating, increase the oxygen atom proportion, and thereby enhance the wettability of the coating surface obviously. However, plasma treatment reduced the corrosion resistance of the PBA coated Mg-alloy to a certain extent, but its corrosion current density was 2~3 orders of magnitude lower than that of the AZ31 Mg-alloy without protective coating and the fluorinated ones. In sum, the PBA protective coating can provide effective protection for Mg-alloy substrate, and the EIS curve also showed the same results. Besides, Cell adhesion on the surface of plasma treated samples increased significantly.

According to the principle of cluster-plus-glue-atom model, the composition of a novel Zr-Cu-Al-Ni alloy with glass formation ability was designed by taking the alloy Zr₅₅Cu₃₀Al₁₀Ni₅ as reference. In the quaternary Zr-Cu-Al-Ni system, two crystallization phases CuZr₂ and CuZr related with amorphous formation were firstly identified, the local structures of these two clusters can be expressed as [Cu-Zr₈Cu₄] and [Cu-Zr₈Cu₆] respectively; then, by combining these two clusters in equal proportion while coupling with the number of glue atoms 2, 4, or 6, the dual-cluster formulas for total atom number of 30, 32, or 34 respectively may be constructed by means of the dual-cluster model. Furthermore, according to dual- cluster formula of the total number of atoms of 32, a quaternary alloy with composition Zr₁₇Cu₁₀Al₃Ni₂≈Zr_53.1Cu_31.3Al_9.4Ni_6.3 was tentatively designed, which is closest to the reference Zr₅₅Cu₃₀Al₁₀Ni₅. The glass formation ability of this alloy was tested experimentally. The results show that its T_rg reaches 0.6 and its crystallization activation energy is 334.138 kJ/mol, which are all slightly higher than that of the reference alloy, indicating that the designed alloy has a higher glass formation ability.

The nitrogen-doped biochar (NBC _x ) was prepared from aloe vera leaf rind with adding urea as nitrogen source, namely the biochar (NBC _x ) was first prepared by hydrothermal method, and then the mixture of NBC _x and urea was pyrolyzed at different temperatures. The as-made NBC _x was characterized by SEM、BET、XPS、FTIR and Zeta, and its application for adsorption of Co²⁺ in waste water was investigated. The results show that the NBC _x has a hierarchical porous structure with a lamellar-like surface with many small flakes. The NBC₈₀₀, prepared with the mass ratio 2∶1 for aloe vera leaf rind to urea by final pyrolysis temperature of 800℃, presents a specific surface area of 32 m²·g^-1, and a total pore volume of 0.04 cm³·g^-1 with the non-microporous ratio of up to 75%. The surface of NBC₈₀₀ is rich in oxygen and nitrogen functional groups, and the content of N and O (mole fraction) is up to 3.89% and 46.35% respectively, which can react with Co²⁺ through ion exchange, electrostatic adsorption, complexation and co-precipitation. The Langmuir model fits well with the adsorption isotherm of Co²⁺ on NBC _x, which demonstrated that the adsorption is monolayered. The maximum adsorption capacity of Co²⁺ on NBC₈₀₀ is up to 228.31 mg·g^-1. The quasi-second-order kinetic model can describe the adsorption process better. The adsorption rate is mainly controlled by chemical adsorption.

In order to solve the problem of coating failure caused by cutting heat due to hard coatings with a high coefficient of friction (COF) when cutting titanium alloy, TiAl-TaN/TaO/WS composite coatings were prepared on cutters by magnetron sputtering. The coatings were composed of Ti buffer layer, TiAl-TaN layer with high wear resistance, TaO with low adhesive property and WS with low COF. The surface morphology of coatings changes from polyhedral granula (of TiAlTaN coating) to spherical granula (of composite coating), but the phase composition and columnar crystal structure of coatings are not affected. The composites can not only reduce the hardness and elastic modulus of the coatings, but also decrease the COF of the coatings from 0.648 of the TiAlN coatings to 0.102 of the composite coatings. Due to the low COF, the composite coatings show beneficial lubrication effect, the life of the cutters with composite coatings is 84% higher than that without coating and 33% higher than that with ordinary commercial coating respectively for cutting titanium alloy. Therefore, it provides a new tool coating that can be used for cutting titanium alloy.

The near-α dual-phase Ti-Al-V-Mo-Nb-Zr alloy series were designed and prepared by copper-mold suction casting in this paper. Their compositions fall within the composition framework previously determined for Ti-6Al-4V: the α and β formulas satisfy the ratio of 12:5, but the β part can be further stabilized, by using multi-element alloying and especially by varying the addition amount of Zr, into the form of [Al-Ti_14-x Zr _x ](Mo_0.6Nb_0.2V_1.2Al), x = 0.6~3. The as-cast alloys are all characterized by a basket-weave microstructure containing a large number of α' martensite needles. With increasing Zr content the α' needles are gradually refined, and the strength and hardness increase accordingly. Among them a Ti-6.7Al-2.2V-2.1Mo-0.7Nb-10.0Zr alloy achieves the ultra-high strength level, with the ultimate tensile strength of 1404 MPa and Vickers-hardness of 451HV, close to the typical ultra-high-strength β-21s after heat-treatment. In comparison with Ti-6Al-4V prepared in the identical conditions, the strength and hardness of this alloy exceeds those of Ti-6Al-4V by 52% and 39%, and the specific strength and hardness are increased by 45% and 33% respectively.

The polyester containing fluorine in its branch chains was synthesized. First of all, one of the functional groups of 1, 2, 4-phthalic anhydride was capped using 1H, 1H, 2H, 2H-perfluoro-1-decanol, then a part of the pentabutyl diacinate was replaced by terminated 1, 2, 4-phthalic anhydride to obtain fluorinated polyester with neopentyl glycol via copolycondensation reaction. After that, films of the fluorinated polyester were prepared by curing with the crosslinker. The structure, molecular weight and thermal stability of fluorinated polyester were characterized by means of IR, XRD, GPC, TG and DSC. The mechanical properties, surface properties and surface element content of fluorinated polyester films were assessed by using universal testing machine, contact angle tester and X-ray electron spectroscopy. The results show that with the increase of the functional groups, the molecular mass of fluorinated polyester increased compared with the non-fluorinated polyester, while the thermal stability of fluorinated polyester increased firstly and then decreased; The maximum initial decomposition temperature is as high as 299.41℃;The glass transition temperature was gradually increased from 6.24℃ to 46.65℃; the elongation at break of fluorinated polyester film decreased while the tensile strength increased gradually, and the maximum tensile strength reached 19.97 MPa. The fluorinated groups migrated from the main body to the surface of the fluorinated polyester film. Furthermore, the water contact angles and the oil contact angles of films increased with the increase of fluorinated groups while the films gained hydrophobicity.