Pb_1-xLa_x)(Zr_yTi_zSn_1-y-z)O₃(PLZST ,0.01≤ x ≤0.05 ; 0.355≤ y≤ 0.70;0.05≤ z≤ 0.20) ceramics with pure complex perovskite phase were fabricated by means of conventional solid state sintering technique. The study shows that it s easier to prepare PLZST ceramics with cubic or orthorhombic structure than those with tetragonal structure. The results also indicate that milling repeatedly, controlling the loss of PbO and sintering at high temperature (1350℃) contribute to the fabrication of the PLZST ceramics with single perovskite phase structure.

MoSi₂ and MoSi₂-based composites have always been paid much attention as important materials for heating and high temperature structural
applications, because of its high melting point(2303K), excellent elevated temperature oxidation resistance and good electrical resistivity. In this
paper, new developments in recent years from international and domestic materials science circles were reviewed in detail, and some impressive
aspects about MoSi₂, including deformation mechanisms, oxidation mechanisms and composite strengthening and toughening, were also briefly
described and summarized. Finally, the present and potential applications of MoSi₂ materials were appraised and prospected, it was suggested that
MoSi₂ could be one of the most promising candidate materials for high-temperature structural applications in the 21-century.

Spinel LiMn₂O₄ is a promising candidate for substitution of LiCoO₂ as the cathode
material for Lithium ion batteries, of which the crystal structure was described in detail. The synthetic methods for the preparation
of LiM_xMn_2-xO₄ developed in recent years were reviewed, including “solid-state reaction methods”such as high temperature
solid-state reaction, microwave sintering, and solid-state coordination reaction, etc., and “soft-chemistry synthetic methods”such as pechini
synthesis, sol-gel method and micro-emulsion method etc. The advantages & drawbacks of each method were compared and analyzed. Of all the methods
described herein, the solid-state coordination reaction method developed by the author is quite a new one for preparing LiM_xMn_2-xO₄, which has
wide application prospects. Compared to the traditional high temperature solid-state reaction method, this new one not only maintains all the former’s
merits such as simple to operate and easy to manufacture in large-scale, but also has many advantages such as low calcination temperature, short
calcination time, and good morphology & small particulate as well as easy control of stoichiometry, etc.

Yttrium aluminium garnet fiber has been paid much attention in material sciences for its high performance such as high tensile strength, oxygen-resistance, creep-resistance and low electroconductivity etc, compared to alumina fiber and other inorganic oxide fibers. This paper summarizes the structure, properties and preparation of the new material.

The luminescence spectra and radiation induced color centers of undoped and various doped lead
tungstate crystals were studied. The radiation induced color centers in all samples (excluding the undoped and Sb doped samples) may be
decomposed into two kinds of color centers peaked at 400 and 500nm, respectively. For undoped samples, the peaks of radiation induced color
centers are at 360 and 530nm, and those of Sb doped samples are at 350 and 430nm. These two kinds of color centers are located at two
sides of the luminescence spectra and with different damage and recovery constants.

The effect of diffusive-advection and diffusive-convection on KNbO₃ crystal morphologies was studied respectively. Under diffusive-advection environment,
the grain grows in dendritic pattern , while, in diffusive-convection, it grows in a pattern that the grain surface is smooth. Based on the fluid effect on solute
concentration distribution near the grain, the influence of fluid effect on morphological stability was analyzed, it is proved that convection can enhance
the morphological stability, this result agrees with the DMSI ( Diffuseness of the Melt-Solid Interface) theoretical calculation. The reason for that the grain
size in diffusive-convective area is larger than that in diffusive-advective area was interpreted. Additionally, the solute concentration effect on KNbO₃ grain
morphologies was also studied qualitatively.

Monodisperse controllable TiO2 nanoparticles were prepared by using the hydrolysis of metal alkoxides(titanium tetrabutoxide) and modification of surface of particles in alcohol solution. The effect of reactive condition including reactant concentration, reactant time and solvent was studied in detail. The properties of particles were analysised by TEM, IR and so on. The experimental results show that TiO2 particles prepared are amorphous, well dispersed, and their particle sizes vary from 50 to 300nm along with the change of reactive conditions.

The 18nm ZnO ultrafine powders with the wurtzite phase were prepared by using a new method of liquidoid
precipitation, and characterized by XRD, TEM. The heat capacities of the powder in 78-370K were also measured with a high precision automatic
adiabatic calorimeter and compared with that of the coarse crystal powders cited from literature. The relation between heat capacities and grain sizes
of the nano ZnO powders was demonstrated in the view of energetics. The results obtained show that the distribution of the nano ZnO powders is narrow,
and their purity is more then 99.9%. The polynomal equation fitted expressing the change of heat capacities with temperatures is C_p=
40.042+24.554X+0.93033X²+2.1649X³-1.8389X⁴.

Precursors were synthesized by solid state reaction of zinc acetate with oxalic acid. ZnO gas sensing materials were obtained by decomposition of the precursors and characterized
by XRD and TEM. La₂O₃ and Nd₂O₃ were doped in nanometre ZnO materials by the methods of solid state and liquid state reaction. The sensitivity
of the materials was measured at various mole ratios of ZnO to La₂O₃ or Nd₂O₃. The gas sensitivity of ZnO element to C₂H₅OH,
NH₃ and LPG were measured in static state at a various operational temperatures. The results show that ZnO prepared by this method is highly sensitive to
C₂H₅OH and selective between C₂H₅OH, NH₃ and LPG at a low operational temperature.

The precipitate with the microstructure of Y(OH)₃ coating Al(OH)₃ was obtained through keeping constant pH value in the co-precipitation processing, and pure YAG phase can be prepared after calcination precipite at 900℃. The special surface area of YAG powder became smaller with the increment of Y, Al solution concentration and pH value controlled during the titration. Nanoscaled YAG powder with the size of 20-30 nm and special surface area of 68m²/g can be prepared by the co-precipitation method.

The adsorption of an acrylic copolymer on nanosized Y-TZP powder was characterized by the method of COD (chemical oxygen demand). The
adsorption density decreases with increasing pH and copolymer concentration. An increase in KNO₃ concentration causes a considerable increase in adsorption density in alkaline region, but has no effect on the adsorption density in acidic region. The
adsorption density in alkaline region increases profoundly in the presence of Ca²⁺ due to the complexation of Ca²⁺ with the
copolymer. FTIR results show the existence of chemical interaction between the metal ions on the powder surface and the carboxylic acid
groups of the copolymer.

The influence of chemical and phase composition on the piezoelectric properties of PMN-PT ceramics with
chemical compositions near the morphotropic phase boundary(MPB) sintered at different temperatures was investigated. It showed that a phase
conversion from rhombohedral to tetragonal phase took place when the sintering temperature of PMN-PT ceramic with a definite chemical composition increased.
Meanwhile, the piezoelectric properties of PMN-PT ceramics were significantly enhanced when the amount of rhombohedral phase approached to that of tetragonal
phase in ceramics. At the same time, it was discovered that the chemical composition corresponding to optimal piezoelectric properties varied with the
change of sintering temperature. Based on above results, the authors found that the piezoelectric properties of PMN-PT near the MPB are not only related
to the chemical composition but also significantly impacted by the phase composition in ceramics. With the change of sintering temperature, the MPB
of PMN-PT ceramic system shifts slightly.

The microstructure and mechanical properties of in situ Al₂O₃ platelet/Ce-TZP composites were studied. The results indicate that both the strength and fracture
toughness of the composites can be increased by introduction of in situ Al₂O₃ platelets if sintered at a suitable temperature. The reinforcement is most effective
for the specimens containing 15 vol% Al₂O₃ while the toughening effects are better than the strengthening. The mechanical properties of the composites decrease
if the sintering temperature is too low or the Al₂O₃ content is too high. The toughening mechanisms in the composites include transformation toughening
and platelet reinforcement. They are enhanced by their co-operation.

Hydroxyapatite (HAP) was prepared by a sol-gel process. XRD, IR, BET measurement and static -dynamic absorption
test were used to study the absorbing mechanism and action, to analyze the specific surface area, degree of crystallization and lattice defect,
crystalline size, thermal stabilization and equilibrium capacities of absorbing F^- ion of the HAP synthesized by changing the molar ratio
of Ca to P and calcination temperature. Test results indicate that the HAP can be used as green environment protection material, as the
result of its strong ability of absorbing F^- ion under the operating conditions of common temperature and common pressure and non-secondary pollution.

A positive active material of spinel LiMn₂O₄ for lithium-ion batteries was synthesized through a modified solid phase reaction. In this process, LiOH and
precursor Mn₃O₄ obtained from controlled crystallization were mixed togather and incinerated to prepare spinel LiMn₂O₄. Structure and electrochemical
properties of the spinel LiMn₂O₄ were studied. The results of XRD and SEM prove that the material prepared through above method is a pure phase of spinel
LiMn₂O₄ and the sizes of the crystallites are uniform. Electrochemical property tests show that the spinel LiMn₂O₄ has excellent eletrochemical

Carbon nanotubes(CNTs) are suitable to make electrodes for electric double-layer capacitors(EDLCs),
because they possess excellent conductivity and suitable surface to form electric double layer. The properties of capacitors are influenced by
binders in electrodes. In our work, phenolic resin and teflon(PTFE) were chosen as binders to carbon nanotubes electrodes. Based on organic electrolyte, the relationship of capacitance property, specific surface and microstructure was studied, and the suitable binder (PTFE)
for carbon nanotubes electrodes was proposed.

Alumina membranes with ordered pore arrays were prepared via anodization in an oxalic or sulfuric acid.
Photoluminescence behavior of porous alumina membranes was studied by annealing the membranes in air or in vacuum of about 1×10^-3Pa
at different temperatures. The results show that the intensity of the photoluminescence (PL) band increases with the annealing temperature and
the PL band exhibits a blue shift at the same time. The intensity of the PL band reaches its maximum for anodic alumina membranes prepared in oxalic
acid when the annealing temperature T_a=500℃. While for membranes prepared in sulfuric acid, the maximum PL intensity appears at
T_a=400℃. When T_a≤400℃, the PL intensities are almost independent of the annealing atmosphere; while the PL intensity of the membrane prepared in the oxalic acid after annealed in
air is higher than that annealed in vacuum when T_a=500℃. The intensity of the PL band is much higher for alumina membranes prepared
in oxalic acid than that prepared in sulfuric acid. Electron spin resonance results verify that the blue PL band comes from the F⁺ centers in porous
alumina membranes. Mechanisms of the photoluminescence characterization of porous alumina membranes were discussed.

By using the average band-gap model, chemical bond properties of BaTi₂Fe₄O₁₁ and
BaSn₂Fe₄O₁₁ were studied. Mossbauer isomer shifts of ⁵⁷Fe, ¹¹⁹Sn in BaTi₂Fe₄O₁₁ and BaSn₂Fe₄O₁₁ were calculated by using the chemical surrounding factor, h, defined by covalency and electronic polarizability. The charge state and site of
⁵⁷Fe and ¹¹⁹Sn were also represented. The calculated results show that the covalency of 2a, 4f, 4e, 6g sites in BaTi₂Fe₄O₁₁
is 0.062,0.354,0.309,0.361 respectively and one of 2a, 4f, 4e, 6g sites in BaSn₂Fe₄O₁₁ is 0.062, 0.353, 0.183, 0.255 respectively.

The preparation of high quality polycrystalline silicon films at low temperature (<600℃) has been recently become one of the hot spots, owing to the requirement
of preparing polycrystalline silicon thin film transistors in the active matrix liquid crystal display on the substrate of common glass. In this paper, the new
process for crystallization of amorphous silicon films, named the metal induced lateral crystallization of amorphous silicon films at low temperatures, was developed.
Aluminium thin films were evaporated on the top of the amorphous silicon films and selectively formed by photolithograph. The films were subsequently annealed in N₂
atmosphere. The crystallization mechanism of a-Si thin film by Al induced was discussed.The results show that the amorphous silicon right under the Al layer can be crystallized
by annealing at 560℃ for 6h and the thin films are polycrystalline silicon thin films.

The poly-Si thin film was passivated by using NH₃ or N₂O plasma before deposition of gate diode. The poly-Si TFTs fabricated with this process have better electrical characteristics than those of conventional poly-Si TFT without NH₃ or N₂O plasma passivation. These devices also have better hot-carrier endurance and thermal stability. Both the nitrogen pile-up at the SiO₂/poly-Si interface and the strong Si-N bond formation to terminate the dangling bonds at the grand boundaries of the poly-Si thin film in the channel region are the major causes.

The V₂O₅ melting prepared under 750, 800 and 1100℃ separately were made into V₂O₅ sol by quenching, and then V₂O₅ gel thin films were obtained by dipping non-crystal glass substrates into V₂O₅ sol. The tetravalence vanadium was found in V₂O₅ gel thin films by measuring the electrical resistance change of V₂O₅ gel thin films with temperature, ESCA and X-ray diffraction analysis. in this paper, from miniamount redox in melting V₂O₅ and crystal structure, the influencing mechanism of miniamount redox on changing valence of vanadium was analyzed and discussed in detail.

The process of chemical synthesis of a new kind of solid lubricant and oil additive--nickel oxythiomolybdate
and one of its precursor material ammonium oxythiomolybdate were studied. Their composition, structure and morphology were investigated by chemical analysis,
X-ray diffraction, electron microprobe and SEM. The results obtained show that their optimum parameters for synthesizing are: pH=4～5, T=30℃, and pH=7～9,
T=--5～0℃. NiMoO₂S₂ as a solid lubricant and an oil additive from 20℃ to 600℃ has good tribological behaviors, and can be regarded as a new kind of lubricant applied in a wide temperature range.

The process and the mechanism of TiB₂/TiC nano-composite powder fabricated via high energy milling were studied, and as-prepared powders were characterized by TIM and XRD techniques. The results show that Ti can react with B₄C during milling process, and TiC is firstly produced, TiB₂/TiC particles formed after 5 hours milling. TiB₂ and TiC phases co-exist in following long time milling. After 30 hours milling, nanosized TiC particles with a diameter of 8 urn are located in TiB₂ particles with a size of 100-200nm.

The nanoparticle structure and nanolayer structure of SiO₂ and C in a silicious gangue were found by Atomic Force Microscope. The size of nanoparticle SiO₂ is 3~20nm, the size of nanoparticle C is 10~20nm and the thick of nanolayer is 5~80nm in the gangue. SiO₂ and C in the gangue are contacted tightly each other.β-SiC ultrafine powder was synthesized at 1300℃ with the gangue. The temperature is lower obviously than that synthesizing SiC with other raw materials mixed under the same conditions. And SiC yield can also be increased greatly.

Y₃Al₅O₁₂:Ce³⁺, Tb³⁺ rare earth phosphor was synthesized through sol-gel methods. The spectra scheme of X-ray diffraction indicates that the powder is with YAG crystal structure. The spectra schemes of excitation and emission indicate that the powder s maximal excitation peak is at 273nm, and the maximal emission peak is at 545nm. Color coordinate is: x=0.334, .=0.558. Excited by 273nm ultraviolet ray, the powder can emit bright green ray.

The nonlinear electrical properties of TiO₂·Y₂O₃·Nb₂O₅ ceramics were investigated as a new varistor material. An optimal
doping composition of 99.75%TiO₂·0.60%Y₂O₃·0.10%Nb₂O ₅was obtained with low breakdown electrical field of 8.8V/mm, high nonlinear constant of 7.0 and ultrahigh
relative dielectric constant of 7.6×10⁴, being consistent with the highest and narrowest grain boundary barriers of the ceramic. The frequency dependence of the
capacitance and the resistivity shows that the samples doped with 0.10%mol Nb₂O₅ exhibit the highest capacitance and resistivity at low frequencies and comparatively low in
comparison with other samples at high frequencies. In view of these electrical characteristics; the ceramic of 99.75%TiO₂·0.60%Y₂O₃·0.10%Nb₂O₅ is a viable
candidate for capacitor-varistor functional devices. The characteristics of the ceramics can be explained by the effect and the maximum of the substitution of Ti⁴⁺ with Nb⁵⁺.
In order to illustrate the grain boundary barriers formation in TiO₂·Y₂O₃·Nb₂O₅ varistors, a grain-boundary defect barrier model was also introduced.

In order to obtain continuous zirconia fibres with high melting point and mechanical properties, newly-produced zirconium acetate was used as a precursor to synthesize
a sol containing Zr-O chains by a sol-gel process and continuous zirconia fibres were produced by dry spinning. The spectral and thermal properties of zirconium
acetate were studied. The sintered fibres were observed by SEM, and their XRD results analyzed, while their tensile strength tested. The results show that a long chain
of Zr-O bond exists in zirconium acetate precursor and the sol has good spinnability and stability. The obtained fibres with diameter under 20μm have certain tensile
strength and toughness. 5mol% Y-doping is effective on stabilizing the tetragonal phase of zirconia.

The EPR (Electron Paramagnetic Resonance) spectra of Mn-doped BaTiO₃ PTCR ceramics measured at 120~450K were studied. The signal intensity, the g factors and the hyperfine splitting constants |A| of Mn²⁺ at different temperatures were calculated. The results show that these parameters obviously correspond to the different phases of BaTiO₃ based PTCR ceramics. This research indicates that EPR method can provide a new way to study upon mechanism of phase transition for PTCR ceramics.

The PTCR (Positive Temperature Coefficient Resistivity) effect of BaTiO₃ based semiconducting ceramics is usually allied to the donor or acceptor. B₂O₃ with
high vapor pressure at high temperatures can be used as vapor dopants. The behavior of B₂O₃ vapor dopants was studied in BaTiO₃ based semiconducting
ceramics. The dramatic results show that the resistivity jumping of the samples is improved distinctly, in the mean time, the room temperature resistivity is also
increased. The enhancement of the PTCR effect of the samples doped with B₂O₃ vapor is possibly associated with the interstice of boron ion and barium vacancy or
their related composite defects.

Iron ion and chromium ion doped TiO₂ films were prepared on the surface of glazed brick by the sol-gel
process, and the effect of iron ion and chromium ion doping on photocatalytic activities of TiO₂ films was investigated. The results
of photodecomposing Rhodamine B show that an appropriate doping amount of iron and chromium ion can improve the photocatalytic
activities of TiO₂ films, however, the photocatalytic activities of iron ion doped samples are remarkably higher than those of
chromium ion doped samples, while the doping ways of chromium ion affect the photocatalytic activities of TiO₂ films, because of their different
doping mechanisms.

Nanosized silver particles embedded silica films were prepared on float glass by the solgel process. The TEM photograph of Ag particles was taken, and the photoluminescence spectra of samples were measured at room temperature. The dependence of luminescent intensity on quantity o f silver doping and drawing speed and thermal treatment temperature was investigated.

A crude conservation film was found that formed naturally on the surface of some historic stone buildings and monuments. It was so well preserved
that the stone inscriptions under the film were not damaged though they were made one more thousand years ago. In this contribution, the composition
and origin of the crude conservation film were focused. The samples of the film were analyzed by FTIR, PLM, EDAX, SEM and TEM. The results show that
the film consists mainly of calcium oxalate and there is a microbial involvement in the calcium oxalate film. There is no clear dividing line between the carbonatematrix and oxalates film. The
transformation layer is about 15μm thick. The thin bioinorganic film is very compact non-porous shell and the calcium oxalate is far more acid
resistant than that of calcium carbonate. The forming mechanism was discussed and the chemical bionics of this crude film was also researched.

By the study of the assembly structure of HP/HT cell of the Cubic Press, some sintering technical problems and the solutions in the use of the enlarged HP/HT cell were proposed. The test results of the samples sintered at different HP/HT cells show that the 25mm-diameter PDC sintered with the improved large HP/HT cell No3 possesses wear-resistance Q 12.3×10⁴ with only 19.2% decrease from the peripheral point to the central point, therefore the even sintering of 25mm-diameter PDC material can be realized.

The process of reaction of silicon carbide ceramics derived from wood was investigated. The reaction
mechanism was also analyzed. The results show that the temperature of silicon infiltration determines the ultimate microstructure of SiC
ceramics. Porous SiC materials are formed at lower temperature, while at higher temperature, compact Si/SiC composite materials formed.
The process of silicon-carbon reaction can be described as three steps: (1) Melted Si ascends via capillary of charcoal and reacts with contacted carbon forming silicon carbide.
(2) The thickness of SiC layer increases toward carbon layer till the end. (3) Reaction-formed SiC will re-crystallize in the later
stage of the reaction, and the ultimate microstructure is composed of large size of polygonal SiC and free Si.