The development of the theories of crystal growth was reviewed and the limitations of present theories were discussed. These limitations
were summed up as: ignorance of the structures of the circumstance phase, ignorance of the growth conditions, the employment of thermodynamics and
statistical physics of equilibrium state to explain non-equilibrium process of crystal growth, and lack of theoretical model on the growth mechanism about
high density circumstance and multi-element crystal system. Moreover, the lately development of the theories and resarch methods about crystal growth was also introduced. Finally, some
opinions about the directions of future development were proposed.

Since the synthesis of novel mesoporous silica materials in 1992, the materials have become a great demand in many research fields. The authors reviewed the synthesis of mesoporous silica materials and their classification, their formation mechanism, as well as the aspects of controlling porosity and recent progresses of their applications. The mesoporous silica materials may be found great utility in catalysis and nano-technology etc.

A detailed review was made on the structure of the carbon nitride together with its preparation process such as sputtering, chemical vapor deposition, ion assisted deposition and laser ablation.The resulting mechanical, electronic and optical properties were discussed, followed by the analysis for further studies.

This paper described the influence of annealing process on X-ray irradiation excited emission spectra, transmission and radiation hardness of PWO crystals grown by a modified Bridgman method. The results show the scintillation properties and radiation hardness of PWO crystals annealed in the atmosphere with oxygen-rich and suitable temperatures are improved obviously.

High optical quality Bi₄Si₃O₁₂ and Fe, Cr doped Bi₄Si₃O₁₂ single crystals with the size 20mm×20mm×100mm were grown by the vertical Bridgman method. After measuring their trans.mission spectra, relative light output, FWHM energy resolution, excitation spectra and emission spectra, the laws of the doped effects on scintillation properties of Bi₄Si₃O₁₂ crystals were summarized and explained.

The electronic structure of rutile TiO₂ crystal with F and F⁺ center was studied using the SCC-DVM-Xα method , and their optical transition models were obtained. We found that F and F⁺ center optical transition energies are 0.98eV and 1.78eV respectively, that the optical absorption peaks of 1.2μm(1.02eV), 740um(1.75eV) in the reduced sample of TiO₂ are due to F and F⁺ center formed, and a transfer of F⁺ →F existed.

The structure of two Ge-As-Te glasses with compositions of Ge₁₀As₁₈Te₇₂ and Ge₁₅As₄₅Te₄₀ were studied by X-ray diffraction radial
distribution function analysis and Reverse Monte Carlo simulation. In the Ge₁₀As₁₈Te₇₂ glass, the Ge, As and Te atoms are bonded on average
to 3.55, 3 and 0.8 Te atoms, respectively. The structure of the investigated Ge₁₀As₁₈Te72 glass can be described as netwok of distorted GeTe_4 tetrahedra
and AsTe₃ (GeTe₃) pyramidal units , connected by --As(Ge)--Te--As(Ge)-- chain-like elements; In the Ge₁₅As₄₅Te₄₀ glass, there is one medium-range order dependent
X-ary scattering feature, i.e.,the first sharp diffraction peak(FSDP). The Ge atoms are bonded on average to 1.8 Te atoms and 1.1 As atoms. The As atoms are
bonded on average to 1.3 Te atoms and 1.0 As atoms. And the length of the Ge--Te bonds and As--Te bonds is shorter in the latter than in the former, respectively.

NiCuZn ferrite nanometre powder and MgO-Al₂O₃-SiO₂ (MAS) gel powder were first synthesized by sol-gel process. Being mixed and sintered, a series
of novel composites with ferrite and MAS glass-ceramic were obtained. XRD resultsrevealed that the composites have diphasic structures of NiCuZn ferrite and
cordierite crystallites. No chemical reaction between two constituents during sintering was detected. The composites have tunable electric and magnetic properties
with the resonant frequencies higher than 2GHz.

Al₂O₃and Y₂O₃-coated SiC composite particles were prepared from SiC coated uniformly with Al(OH)₃ and Y(OH)₃ by
heterogeneous nucleation process. The IEP of as-received SiC is pH 3.4, that of Al(OH)₃-coated SiC shift to pH 7.3. When Al(OH)₃-coated
SiC composite particles were coated with Y(OH)₃, its IEP is about pH 8.6. In addition, the viscosity behavior of SiC was changed via coating. The
coating ratio is over 95% according to the results of hydrochloric acid titration, that is, 95% of added coating materials can be coated on the surfaces of SiC
particles by heterogeneous nucleation process.

The precursor of Li ferrite with a solid solution structure was prepared by mechanochemical treatment of Li₂CO₃ and α-Fe₂O₃
powders through high energy ball milling. Li ferrite was obtained after heat treatment of the precursor under a temperature much lower than that
required in general solid state reaction. LiFeO₂ was the intermediate of the formation of Li ferrite. The ferrite was characterized by
Mossbauer spectra, XRD, IR spectra, TEM and VSM methods. The results showed that the ferrite was nanoparticles with ordered
structure of Li⁺ and Fe³⁺ ions in the octahedral sites of the ferrite. The magnetization of the ferrite nanoparticles was higher than that of
the samples synthesized by wet chemical method and the coercivity of the ferrite was higher than that of the bulk ferrite.

Nanometer-sized ZnO particles were prepared by using a homogeneous precipitation method, urea and zinc nitrate as the starting materials.
Microstructure and morphology of nanometer-sized ZnO were investigated by means of TG-DTA, IR absorption spectra, X-ray diffractometry
, TEM and Laser particle size analyzer. The results indicated that well-crystallized nano-ZnO was obtained with annealing temperature at 450℃. Narrow-
sized, finely dispersed nano-ZnO with a size of 15～80nm was available by controlling reactant conditions. The effects of supersaturation on particle
sizes and formation mechanism of nano-ZnO were also discussed.

In the process of electroless plating used to Ni coated ZrO₂ ultrafine powders, the relationship between Ni²⁺ concentration in solution
and time at different temperatures was determined. The effect of Ni²⁺ concentration, NaF and surfactants on the speed of Ni deposit was obtained.
Apparent activity energy was concluded. The goal that even mixing Ni with ZrO₂ was attained. Experimental results show that
Ni is coated on ZrO₂ powder surface and the speed of Ni deposit can be raised and apparent activity energy can be dropped by NaF and surfactants.

Refractory grade β-St₃N₄ powder was pressureless sintered with the aim of lowering cost. It is showed that β-St₃N₄ has good sinterability. A microstructure with small rod-like grains was obtained, which dispersed uniformly in the matrix, no abnormal rod-like grains was observed. The material displayed a strength of 587MPa and fracture toughness of 5.3MPa.m^1/2, which allow the material used in normal circumstance.

Grain boundary effect is one of the characteristics of ceramic materials. Some oxides have high vaporization pressure. Using vapor as doping resource
during sintering, the grain boundary behavior can be effectively controlled and the material properties can be improved. The PTCR effect that existed in
semiconducting barium titanate based ceramics is a typical grain boundary effect. The experimental results show that materials doped with Sb₂O₃ or Bi₂O₃
vapor have high density and homogeneous microstructure with small grain size. The sample with over 8 orders of magnitude degree of resistivity jumping can be
obtained. Thus vapor doping method is a new and effective method.

Because of slow polarization and non-linear effects, the dynamic properties of Metal-Semiconductor-Insulator-Metal (MSIM) layer were obtained incorrectly by frequency domian spectra with sinusoidal current. For this structure, time domain dielectric spectra can distinguish the effects reliably between contact and insulating layer of MOS structure. More important information of space charges motion can also be obtained by this method.

The PZT-based monolithic multilayer piezoelectric actuator (35 layers of piezo-ceramic, one layer 47μm thick) was fabricated by the tape-casting and the ceramic/internal-electrode cofiring method. The actuator shows large displacement under a low voltage (about 1μm displacement under 38V voltage). The static and dynamic displacement characterizations of the PZT-based actuator was discussed on the basis of its lattice structure and domain behaviors.

A surface diffusion method was proposed and applied to prepare blue phosphor BaMgAl₁₀O_l7 :Eu²⁺. The results show that, compared with the direct synthesis method by common high temperature solid state, the concentration of Eu²⁺ in the phosphor BaMgAl₁₀O₁₇:Eu²⁺ prepared by the surface diffusion method can be greatly reduced owing to the activator Eu²⁺ ions distributed mainly over the surface of the phosphor. It is possible to reduce the cost of this kind of the luminescent materials with the aid of the surface diffusion method.

The thickness of amorphous silicon dioxide on the surface of fine quartz was detected by TEM，SED and EDS methods and its volume and weight content computed.
Moreover, its effect on the hollow secondary particles of xonotlite produced by hydrothermal reactions was studied. Reaction products were investigated by XRD
and SEM methods. The experiment results show low content of amorphous silicon dioxide in the surface has no effect on the formation of the hollow secondary
particles of xonotlite, but high content delays their formation and leads to produce aggregates of xonotlite and tobermorite crystals.

h-BN-SiO₂ ceramics were prepared by means of high pressure gas-solid self-propagating high temperature synthesis technology from powders of B, h-BN
and SiO₂. The nitrogen pressure and porosity of reactants that influence on ignition, and products have a scope, 48%≤ρ≤52%, 75MPa≤ρ≤85MPa, in which
the non-cracked combustion products can be obtained. The density of product is up to 1.79g·cm^-3 and the bending strength and hardness of h-BN-SiO₂ ceramic
are up to 76MPa and 212(HV) respectively. The higher the nitrogen pressure, the bigger the h-BN particles. The h-BN particles are isotropy. Crystalline B₇O and glasses
SiO₂ exist in the product. Crystalline SiO₂ was disappeared because of rapid cooling from combustion temperature to 1000℃. Glass’s phases that are not
found among the h-BN particles only exist at the edge of B₇O, which demonstrates that SiO₂ is the cause of B₇O formation.

Dense TiC-Ni cermets TH20 and TH30 were produced by self-propagating high-temperature synthesis and pseudo heat isostatic pressing. The influence of process parameters
on densities was investigated. Cermet mainly consisted of TiC particles and Ni-binder. TiC skeletal structure was enveloped by continuous Ni-binder phase. The interfacial bonding
between TiC and Ni was found to be of a good quality. High dislocation existed near the interface and inside the Ni-binder phase, some residual carbon exists in
reaction product. Meanwhile transverse rupture strengths of TH20 and TH30 were both close to those produced by conventional technology.

Four compositions of nitrogen-containing Dy-melilite solid solutions Dy₂Si_3-xAl_xO_3+xN_4-x (Dy-M’, x=0, 0.3, 0.6 and 1.0) were prepared by hot-pressing
and oxidized at 1000℃ for 20h in air in a TG unit. The weight gains per area of Dy-M’ samples decreased with increasing the Al substitution, i.e.
Dy-M’(x=0.6)<x=0.3)M’, especially for Dy-M’(x=0.6), became better compared with that of Dy-M.
A composition of Dy-α-Sialon with Dy-M’ as the grain boundary phase prepared by hot-pressing was exposed to air at 1000℃ and 1300℃ for
20h. No catastrophic oxidation behavior was observed in the first situation. When the sample was oxidized at 1300℃ for 20h, crystals of
α-Dy₂Si₂O₇ were observed in preferred orientation on the oxidized surface of Dy-α’-M’ sample.

α-Al₂O₃ powder, AlO(OH) fibers and complex oxides made up of ZrO₂ and AlO(OH) were prepared by a new hydrothermal method-hydrothermal salt
solution pressure-relief. α-Al₂O₃ powders were prepared at 300℃ by using 1mol/L Al(NO₃)₃ solution as precursor, 0.2mol/L Fe(NO₃)₃ as additive; AlO(OH) fiber with the ratio of length with
diameter 13:1 were prepared at 350℃ by using 1mol/LAl(NO₃)₃ as precursor, 1 mol/L KBr as additive; complex oxides made up of ZrO₂ and AlO(OH) were prepared
at 240℃ by using 0.75mol/L AlCl₃ and 0.25mol/L ZrOCl₂ mixed solutions as precursor.

Nanometer TiO₂ particles were prepared by forced hydrolysis of boiling reflux conditions from Ti(SO₄)₂ of high concentrations. The specimen was characterized by IR, TEM and XRD.The results show that the TiO₂ particles obtained are spherical and their sizes are 20~30um.

Two factors which influence the measurement of particle size distribution were discussed. Selecting proper ultrasonic time can decrease the agglomeration of
powders and lower the average particle size. Three kinds of nano-size Y-TZP powders require different amounts of dispersant to achieve lowest particle
size. The optimum amount of dispersant for TZP1, TZP2 and TZP3 is 1.186%, 1.186% and 0.237% respectively. No significant improvement in the degree of dispersion
was observed when the amount of dispersant exceeded the optimum value. The adsorbed polyelectrolyte results in a significant zeta potential on the particles and sterically
prevents the particles from flocculating, leading to colloid stability increased. The pH of suspension is near to weakly basic (pH=8.0) if NH4PAA is added even as little as 0.237%.

CuTi-Diamond composite was first made by microwave sintering. The process and structure of the composite was studied. Results show that graphitization of diamond was not observed during sintering at 950℃. Diamond bonds well with CuTi matrix. The density of composite increases initially as the diamond content increases and then decreases after passing a maximum at the diamond volume content of about 18.75~25vol%.

Compounds of Nd_0.67(Sr,Ca)_0.33Mn(O,F)₃ (NSMO) with colossal magnetoresistance (CMR)were prepared with CaF₂ as dopant. X-ray diffraction with Rietveld analysis showed that NSMO compounds were of perovskite structures, with space groups of Pbnm, Z=4, and F- occupying 8d positions. As more amount of CaF₂ were used, the lattice parameters and To of NSMO declined.The magnetoresistance (-△R/R) increased to a maximum of 99.7% when 20mol% CaF₂ was doped.

Sol-Gel and microwave radiation methods were used to synthesize the phosphors of silicateoxyapatites doped with Mn²⁺. The high efficient, green color, subnanometer phosphors Zn₂SO₄:Mn²⁺ with 150~350urn particle sizes were obtained.

Layered and highly crystalline LiNiO₂ was prepared by heating a mixture of lithium hydroxide and nickel hydroxide at high temperature. The influence of preparation conditions on the electrochemical behavior of the product was discussed. It was found that tempwrature and duration of reaction as well as Li/Ni mole ratio exert important effects on the electrochemical behavior of the product. LiNiO₂ prepared in this work has a reversible capacity of about 140mA.·h/g.

Dense TiC-Al₂O₃ composites were produced by self-propergating high temperature synthsis and pseudo-hot isostatic pressing(SHS/PHIP). The composition, microstructure and properties of the product were analyzed. The results show that the product consists of quasi-spherical TiC and irregular Al₂O₃. The interfacial bonding between TiC and Al₂O₃ is smooth. Transverse rupture strength and hardness of TiC-Al₂O₃ composites are aproximately 510MPa and 17.8GPa.

The effect of a dispersant on the electrokinetics and rheology of silicon nitride aqueous suspension with solids loading of
50wt% was investigated. The results indicated that the isoelectric point (IEP) of the silicon nitride powders is at the pH value of 4.2, and the
value of zeta potential is up to its maximum near pH value of 11. The IEP of the silicon nitride powders decreases with the addition of the dispersant and
the shift dependents on the amount of the dispersant. The suspension is a non-Newtonian time-dependent fluid. The optimum amount of the
dispersant is at the ranges from 0.8 to 1.2wt%, in which the suspension is near Bingham fluid. Beyond that range, the suspension
exhibits thixotropic behavior, or the suspension is an anti-thixotropy.

Co-precipitation methods were used to produce 20 mol% Al₂O₃-ZrO₂ powder, from aqueous solutions of zirconium
oxychloride and aluminium chloride, followed by precipitation with ammonia. The resulting gel was calcined at 750℃. The prepared powder was sintered at 1000℃ for 1 h under
200 MPa by using the hot isostatic pressing technique. TEM micrograph showed that the average grain size of the sintered body was only about
50 nm. XRD analysis on the polished surface indicated the phase composition of the nano-ceramics was 55% t-ZrO₂-39% m-ZrO₂-6%
α-Al₂O₃.

A trial tubular SOFC system was fabricated. The electrical performance of this SOFC was evaluated at temperatures of 500 to 950℃. H₂ and CH₄ were used as the fuels and air as the oxidant
gas. The internal resistance, output current and output power of this SOFC were measured. When H₂ and CH₄ were imported into the SOFC system
at 950℃, the open circuit voltages were 0.98V and 1.05V, maximum output current densities were 19.6mA/cm² and 16.4mA/cm², the maximum output power was 30.0mW and 24.4mW, respectively. The endurance test was conducted over 145h, but this SOFC system showed no significant degradation.

The preparation process of Pd/γ-Al₂O₃ composite membrane for selective hydrogen separation was studied, direct impregnation of pd was achieved by mixing the boehmite sol(γ-AlOOH) with a Pd precursor, followed by ultrasonic dispersing Pd particles uniformly throughout the membrane.The average pore diameter measured by BET was 2.5~4.0nm, SEM, XRD and separation tests were conducted in order to evaluate the properties of the composite membrane.

A three-dimensional optical in-situ observation method was newly developed. The transmission magic-mirror method was applied to visualize and record the whole process of growth and melting of transparent crystals taking place in high temperature up to 1000℃ For matching to three-dimensional observation, a set of special furnace and crucible was designed and the growing process can be observed in two perpendicular directions and recorded in situ by CCD camera simultaneously. By using this system, the proces of KCl dendrite growth was observed.