For further improvement of the compatibility between chitosan(CS) and hydroxyapatite (HA), surface modification of HA was carried out with CS to prepare hydroxyapatite-grafted-chitosan (HA-g-CS) The results of FT-IR, TGA and XRD show that CS was successfully grafted onto HA surface, SEM observation showed that the dispersity of HA-g-CS in the CS matrix was significantly improved, and the CS/HA-g-CS hydrogel exhibited much more better compression performance than that of the CS/HA. The biocompatibility evaluation showed that the CS/HA-g-CS composite hydrogel showed no cytotoxicity and implantation safety in vitro according with the requirement of national standards, and was expected to be served as a potential scaffold material applied in tissue engineering.

Ultra high molecular weight polyethylene (UHMWPE) fibers possess outstanding properties such as high tensile strength and low density. However, their low surface polarity and poor heat resistance restrict the application of UHMWPE fibers as a reinforcing material for high performance composites. These shortcomings of UHMWPE fibers can be overcome by ultraviolet (UV) assisted grafting treatment and hybridization with aramid fibers. Results show that UHMWPE fibers could firstly be modified by means of an UV radiation assisted one step grafting process with acetone as solvent and acrylic acid as monomers, then the mechanical properties of composites of epoxy resin with the modified UHMWPE fibers was greatly enhanced; with the increasing monomer content in the acetone solvent, the tensile strength of UHMWPE fibers/epoxy resin composites increased obviously, while there was no significant change of flexural strength and impact strength. In order to further improve the heat resistance of UHMWPE fibers/epoxy resin composites, UHMWPE fibers were hybridized with aramid fibers and then the hybrid fibers were used as reinforcing material to produce hybrid fibers/epoxy resin composites. As a result, the deformation of the hybrid fibers/epoxy resin composites decreased by 66.7% at 90℃ compared to that of UHMWPE fibers/epoxy resin composites. The result proves that the pre-hybridization of UHMWPE fibers is an effective means to enhance the heat resistance of UHMWPE fibers/epoxy resin composites .

A new melamine-urea-formaldehyde (MUF) resin was prepared with concentrated formaldehyde and degradated liquid of soy-protein as raw materials . The molecular structure and thermal mechanical properties of MUF resin were characterized by ¹³C-NMR, FT-IR and DMA. The prepared MUF resins were used as bonding material to fabricate particleboards and then their bonding strength and modulus of rupture(MOR)as well as free formaldehyde content were also examined. The results show that with the MUF resin synthesized merely with concentrated formaldehyde (hereinafter named MUF resin-F), the bonding strength and MOR of the fabricated particleboard increased by 25% and 64%, and the free formaldehyde content decreased by 52%; however, with the MUF resin synthesized jointly with concentrated formaldehyde and degradated liquid of soy-protein (herinafter named MUF resin-FP), the bonding strength and MOR of the fabricated particleboard increased by 48% and 97% respectively, and the free formaldehyde content decreased by 56%. The FT-IR results indicated that the degradated liquid of soy-protein did react with MUF. ¹³C-NMR and DMA results indicated that the MUF resin-F has high amount of ether bond and high condensation degree, high initial strength and low thermal stability; in the contrast, the MUF resin-FP has high condensation degree and high amount of methylene bridge bond, which can offset the instability induced by the fracture and rearrangement of ether bonds. In sum, the newly synthesized MUF resin-FP possesses good thermal mechanical properties, high strength and low free formaldehyde content.

Multi-interlayers of SiC/TaC ceramics gradient distribution were inserted into C/C composites by means of chemical vapor infiltration (CVI) and controlling the flow direction of reaction gas in the porous C/C preforms. The results show that, along the thickness direction of C/C composites, the content of SiC/TaC ceramic phase and the thickness of the multi-interlayer are decreased, while the structure of the ceramic phase also changes from multi-interlayer (Region I) to composite interlayer (Region II) and then single interlayer (Region III). In Region I, the SiC/TaC multi-interlayer is composed of five interlayers: the first SiC layer, the second TaC layer, the third TaC composite interlayer embedded with SiC particles, the fourth SiC composite interlayer embedded with fine mosaic-like TaC phase and the fifth white TaC layer. In Region II, the ceramic phase does no longer coat on the surface of carbon fiber in form of an interlayer, but of a cauliflower-like cluster. At last, the nano-hardness and elastic modulus of SiC/TaC ceramic multi-interlayer in Region I were also discussed.

The La_0.6Pr_0.4Fe_11.4Si_1.6B_0.2 alloy was produced by using industrial grade raw materials. The phase constituents and thermal magnetic properties of the alloy were characterized by X-ray diffraction with Cu kα radiation and vibration sample magnetism respectively. The influence of hydrogen absorption pressure on magnetocaloric effect and hydrogen desorption process were investigated. Results show that the annealing treated alloy was subjected to hydrogenation at 0.13 and 0.2 MPa, correspondingly its Curie temperature increased to 320 and 321 K respectively. The taking place of dehydrogenation was much easier for the alloy hydrogenated at lower absorption pressure rather than that at higher pressure. The Curie temperature of the alloy hydrogenated at 0.13 MPa and then dehydrogenated at 473K could lower to room temperature range, correpondingly the maximal magnetic entropy of the hydrides decreased while the relative cooling power were increased.

To improve the properties of dye-sensitized solar cells (DSSC), three-dimensional ordered TiO₂ hollow spheres (3DOHS-TiO₂) films were synthesized using polystyrene spheres (290-300 nm) colloidal crystals as sacrificial templates. The photoelectric conversion performances of the DSSC based on double-layered films P25-TiO₂/3DOHS-TiO₂ were investigated. SEM results show that the orderly arranged TiO₂ hollow spheres form hexangular and square arrays, and the hollow spheres connect to their neighbors through pores. The center-center spacing of the 3DOHS-TiO₂ is 260-270 nm, and the thickness of the hollow shells is 40-50 nm. TEM results show that the shell is composed of a lot of tiny particles resulting in a mesoporous framework. The mean size of the anatase TiO₂ nanoparticles of the shells is ca.10 nm as estimated from the HRTEM image. By compared with the P25-TiO₂ nanocrystalline DSSC (η=4.32%), the DSSC based on the double-layered films P25-TiO₂/3DOHS-TiO₂ exhibit a higher photoelectric performance (η=6.98%). The enhancement of the cell performance can be attributed to the enhancement of light harvesting of the light scattering ability of the layer 3DOHS-TiO₂.

An active tertiary hydrogen atom containing poly (butyl methacrylate-co-butyl acrylate)was firstly synthesized via suspension polymerization, and then a novel functional resin containing rigid calcium carbonate was prepared by reactive extrusion while poly (butyl methacrylate-co-butyl acrylate), nano-calcium carbonate, hydroxyethyl methacrylate and benzoyl peroxide were used as matrix polymer, filler, reactive monomer and initiator, respectively. The corresponding structure and properties of the prepared resin were characterized by using thermogravimetric analyzer, field emission scanning electron microscope and X-ray diffractometer. The oil absorption of the resin before and after acid treatment and the capability of the resin before and after alkali treatment to absorb cationic blue dye were investigated in detail. The results show that acid treatment can not affect the oil absorption of the resin, and the resin can completely remove oil from water through absorption when circulating absorption time reached 50-60 min; additionally, the composite after alkali treatment for 30 min has good capacity to absorb cationic blue dye in comparison with the untreated ones.

Mg doped hydroxyapatite coatings with 0, 0.28%, 0.32%, 0.49% Mg respectively, as artificial human bones were prepared on carbon / carbon composites by means of electromagnetic induction method. Then they were characterized by SEM, EDS, X-ray diffraction and Fourier transform-infrared spectroscopy etc. The results show that Mg ions entered the hydroxyapatite lattice and these coatings have only a little difference in constituents. Within the range Mg content of human bone, Mg ions can enhance the adhesion, multiplication, and differentiation of external osteoblasts.

The volume fraction, morphology and size of reversed austenite in 5.5Ni steel tempered at different temperatures were characterized by X-ray diffraction, scanning electron microscope and transmission electron microscope, and the influence of tempering temperature on mechanical properties of 5.5Ni steel was investigated. The results show that there was no significant change in either the tensile strength or yield strength for the steel tempered in the range from 580℃ to 600℃. There was a slight increment in tensile strength but a great decrement in yield strength, besides, a maximum elongation was obtained for the steel tempered at 620℃. As the tempering temperature increased from 580℃ to 620℃, the volume fraction of reversed austenite in 5.5Ni steel increased gradually but impact energy decreased. Stable, homogeneous, dispersive and fine lamella-like reversed austenite is the main reason of the high impact energy of 148 J when the steel tempered at 580℃. Two types of reversed austenite including lamella ones and block ones were detected in this steel. The former had different length with a width of about 20 nm which could improve the low temperature toughness of the steel. The latter had a size of about 200 nm and tended to gathering together as clusters which were detrimental to the low temperature toughness of the steel.

A hexadecanol-palmitic acid-lauric acid/SiO₂ composite as phase change material for humidity control was prepared with SiO₂ as carrier and hexadecanol-palmitic acid-lauric acid as phase change material. The performance, molecular structure and morphology of the prepared composite were characterized by using methods of isothermal sorption, cooling curve, FT-IR, SEM, LPSA, TG, DSC and so on. The results show that SiO₂ was good coated with hexadecanol-palmitic acid-lauric acid; the prepared phase change material exhibits good performance both in temperature- and humidity-control.

Glass ceramics of CaO-Al₂O-MgO-SiO₂ (CAMS) with addition of 0-8.73%(mass fraction) Nd₂O₃ were synthesized mainly with the tailings of Bayan-Obo west mine by melting-casting method. The influence of the amount of Nd₂O₃ on the microstructure and properties of the glass ceramics was systematically investigated by DTA, XRD, FEGSEM equipped with EDS EBSD attachments and universal mechanical properties tester. The results show that the average grain size of the primary crystalline phase, augite (Ca(Mg, Al, Fe)Si₂O₆), decreases with the increase amount of Nd2O3 addition, and the main reason can be ascribed to the hindering effects of Ca₂Nd₈(SiO₄)₆O₂ particles and the consumption of Ca²⁺ ions by the formation this newly formed Nd-rich phase on the grain growth of augite crystals during the heattreatment process. The glass ceramics with 2.21% Nd₂O₃ shows the optimal properties, i.e. of which the density, bending strength and the resistance to acid or alkali corrosion are 3.20 g/cm³, 200 MPa, 95.22%and 99.23%, respectively.