Model experiments were designed in order to obtain more reliable data on the diversity of some crystal
forms and polyhedral instability-skeletal and dendritic growth in high temperature solution growth. These experiments were performed by High
Temperature In Situ Observation Technique. Most of our investigations on high temperature solution growth were performed in a
loop-shaped Pt wire heater, having a diameter about 2mm. The Pt wire (φ～0.2mm) was used to heat and suspend the solution. A mixture of KNbO₃
(20wt%) and Li₂B₄O₇ was chosen for growth. Rapid growth, and hence diffusion mechanism limitations can result in various imperfections;
such as the formation of cavities in the facets, skeletal and dendritic patterns. Quenching experiments were designed to distinguish some KNbO₃ crystal forms, and the morphology of KNbO₃
crystals grown in Li₂B₄O₇ solution was studied with a scanning electron microscope. In all cases, when the crystal is nucleated near
air/solution interface, it looses its polyhedral stability. The thickness of this shape destabilizing solution layer is about 60μm. The
morphologies of crystals observed by a scanning electron microscope, vary in the layer from polyhedrons to dendrites. Anisotropic aspects
of skeletal and dendritic structures reflect the cubic nature of KNbO₃ as well as the fact that instabilities amplify and propagate
along the four (110) crystal edges. The side branches in the four (110) directions provide convincing evidence for the growth shape anisotropy.
The value of the critical size for loss of polyhedral stability is about 10μm. In contrast, the stable shape of the faceted crystal is generally
retained with adequate reproducibility for all crystals grown in the solution beneath the shape-destabilizing layer. The polyhedral crystal
growth processes were in-situ observed and recorded by HITISOT. The thermoconcentrational driven convection (i.e.microconvection) around
the solid-liquid interface of the polyhedral crystal was also visualized.

The nucleating mechanism of crystallite was investigated from the microcosmic kinetics. It was proposed that the idealized
nucleation mechanism consists of the formation of growth unit, the oxolation reaction, and the transform of O bridge into OH bridge. The main factors affecting the particle
size of powders were analyzed from nucleating rate. It was concluded that the interior factors affecting the particle size of powders are the formation energy of growth unit
and lattice energy of crystal. The relative particle size of various oxide powders as a function of structure type was summed up from this. The particle size of powders with
the structure type of CaF₂ or TiO₂ is smaller than that of powders with the structure type of α-Al₂O₃; the particle size of powders with the structure type of
α-Al₂O₃ is smaller than that of powders with the structure type of ZnO. According to above analysis, the difference in particle size of various oxide
powders prepared by hydrothermal method, and the effect of the reaction medium and the reaction temperature on the particle size were reasonably explained.

The silver halide fibers were made by hot extrusion. The microstructure of the fibers changed after thermal treatment at different temperatures. SEM
micrographs showed that the microstructure of the fibers did not change when temperatures of thermal treatment T<170℃, and their grain sizes were
1～2μm. The grain size grew up when T>170℃. The relation of grain size and T was as follows: 10～20μm, T=200℃; 20～30μm,
T=250℃; 30～40μm, T=300℃, respectively. The measurements of microhardness also showed that the microhardness of the fibers decreased as temperatures of thermal treatment
increased when T>170℃ and the lowest microhardness appeared at 200℃.

CaS:Mn²⁺, Eu²⁺ phosphor materials were firstly synthesized in microwave field. The materials synthesized were characterized by XRD, SEM and the fluorescent spectroscopy. The experimental results of XRD
and SEM show that the CaS:Mn²⁺, Eu²⁺ phosphors possess the crystalline structures with sphere, the mean grain sizes of phosphors are
250-400nm. The introduction of Mn²⁺ into CaS:Eu²⁺, makes the fluorescence of the CaS:Mn²⁺, Eu²⁺ phosphor efficiently
enhanced since the energy transfer from Mn²⁺ into Eu²⁺ ions. This new synthesis method compared to the traditional high temperature
solid reaction exhibits interesting features, such as rapid reactions without H₂-H₂S protective atmosphere, phosphors with high purity,
submicro-scale crystallines, and higher efficient luminescence.

Nanocrystalline (Ba,Pb)TiO₃ (5 mol% Pb) with various grain sizes were prepared by a sol-gel process. The gain size, structure and phase properties of nanocrystalline BPT were studied by TEM, XRD and DSC. The results show
that the structure phase transition is from ferroelectric tetragonal to paraelectric cubic phase and becomes more diffusive with decreasing particle size.
On the other hand, the ferroelectric orthorhombic to ferroelectric tetragonal phase transition disappears with increasing particle size, it means that the
formation of the unwanted orthorhombic phase of BaTiO₃ is inhibited.

A nano-grade α-MnO₂ was prepared by a sol-gel method. The optimum condition to form α-MnO₂ was
discussed. The measurements such as XRD, TG, SEM, ICP, TEM, chemical analysis，constant current discharge，cyclic voltammetry test, were performed
and compared with that of I.C.No.1 (international common MnO₂ sample No.1EMD). Although the discharge performance of the nano-grade α-MnO₂ is not better,
the discharge capacity of the nano-grade α-MnO₂ mixed with I.C.No.1 at a certain weight ratio is higher than that of I.C.No.1 in shallow and deep
discharge stages.

Phase structures，properties and critical parameters of field-induced phase transitions of PZST ceramics
near ferroelectric(FE)-antiferroelectric(AFE) phase boundary were studied as a function of composition and temperature．The electric field-induced FE
state can maintain metastable state below the critical temperature T_FE-AFE after electric field is removed．As temperature increases，
the metastable FE state changes to AFE state at T_FE-AFE．As Ti content increases，the structure of unpoled PZST ceramics changes from
tetragonal AFE phase to rhombohedral FE phase，dielectric constant maximum ε_max and transition temperature T_FE-AFE increase，
switching field E_AFE-FE and E_FE-AFE decrease．The forward switching field E_AFE-FE and hysteresis Δ E were observed to
be dependent on T_FE-AFE and T_c，respectively，and E_AFE-FE and Δ E decreased with an associated increasing in T_FE-AFE and decreasing in T_c．

For (1-x)Na_1/2Bi_1/2TiO₃xBaTiO₃(x=0.02, 0.04, 0.06, 0.08, 0.10) lead-free ceramic system the morphotropic boundary, piezoelectric property, relaxation
property and phase transition were investigated. The piezoelectric ceramics of this system possess large ratios of K_t/K_p and high frequency constants.
According to XRD patterns, the morphotropic boundary lies in the composition range of 0.04<x<0.06. The main physical properties of this system can reach
extreme values near the morphotropic boundary. The relaxation property of this system was studied by using dielectric constant-temperature curves and
thermally stimulated depolarization current (TSDC) curves. Phase transition from ferroelectric to paraelectric phase was also primarily discussed and
it was found out that the ceramics within a composition range possess transitional phase region between ferroelectric phase and paraelectric phase.

The SnO₂ thick film gas sensors were prepared by using a standard screen printing technology and calcined at different temperature and time. By measuring
the sensitivity and long-term stability and using complex impedance analysis, the effects of calcining temperature and time on sensing properties and microstructure
of the thick films were researched. Gas sensors with high sensitivity and long-term stability can be prepared by choicing suitable calcining process parameters. Complex
impedance analysis indicates that the depressed angles of semicircular arc will reduce to zero with the extension of calcining time. The reducing of depressed
angles means the distribution of relaxation time at the grain boundary becomes more uniform. This result shows that the distribution of defects and pores, and the grain
connected shapes at the grain boundary tend to be more uniform and stable with the extension of calcining time.

The internal friction Q^-1 of Lead Metaniobate ceramics was investigated by inverted torsion pendulum.
Six internal friction peaks, with their location around 70℃(P₁), 90℃(P₂), 200℃(P₃), 260℃(P₄), 430℃(P₅) and 510℃(P₆), respectively, were observed
in a freshly-worked PbNb₂O₆ ceramics. The mechanisms for P₃, P₁, P₂ and P₄ were analyzed in detail. P₃ is a broadened Debye relaxation peak in nature, and its corresponding activation
energy and pre-exponential factor are 1.01eV and 2.5×10^-12s, respectively. This peak is attributed to the interaction between domain walls and oxygen
vacancies. P₁, P₂, and P₄ are clearly related to the working processes. They can be caused by the interaction between dislocations and point defects.

The effect of doping ZrO₂ on the electrical conductivity and strength of CeO₂/Sm₂O₃ ceramics was
investigated, and the microstructure of samples was studied and analyzed by means of XRD and SEM. The results showed that doping ZrO₂ could decrease
the electrical conductivity. It was attribute to the reason that solution of ZrO₂ in ceria-based electrolyte reduced the lattice constant. Doping ZrO₂
increased the fracture strength and the fracture was intergranular for the reason that ZrO₂ toughened the grain-boundary. Ceramics doped with ZrO₂ were
dense as well. (CeO₂)_0.86(SmO_1.5)_0.14 doped with 2.5mol% ZrO₂ may be a potential electrolyte material used for SOFC for its proper
electrical conductivity and strength.

(1-x)PNN-xPT(x=0.30～0.40) ceramics were prepared by a two-steps synthesis method. Phase structure and dielectric properties were studied.
Morphotropic phase boundary exists in (1-x)PNN-xPT system at about x=0.34～0.38 composition range according to XRD analysis. Dielectric properties
measurments showed that the optimum value of dielectric constant was obtained and the phenomenon of dielectric dual peaks was found for composition near the
morphotropic phase boundary. One dielectric peak is phase transition peak from relaxor ferroelectric phase to paraelectric phase. The other peak lying in 130～150℃ temperature range results from relaxational polarization
of the valence change of Ni ion and kinds of defects in (1-x)PNN-xPT system.

Under mild experiomental conditions, with 3-aminopropyltriethoxysilane as the coupling agent, mesoporous molacular sieve MCM--41(Si/Al=35) was modified,
and --(CH₂)_3NH₂ organic functional group was successfully introduced into the pore of the mesoporous sieve, the organic/inorganic complex material MCM--(CH₂)₃NH₂
was synthesized, and characterized by XRD, FTIR, DTA-TG, nitrogen adsorption-desorption at 77K and HREM. The results of the characterization show that --(CH₂)₃NH₂
not only gets into the modified inner wall of mesoporous MCM-41, but also makes MCM--41 remain its ordered pore structure.

Mixed ionic electronic conductor La_0.6Sr_0.4Co_0.2Fe_0.8O_3-δ in the porous form can be used as cathodes for solid oxide fuel cells and
supports for thin oxygen separation membranes. La_0.6Sr_0.4Co_0.2Fe_0.8O_3-δ porous ceramics were prepared by solid state reaction. The porosity and
pore size were investigated as a function of sintering temperature, molding pressure and amount of organic additive. The experimental results show
that with increasing porosity, its nitrogen permeability increases, but its electrical conductivity decreases as described by σ=σ₀·(1-P)^3.1.

2-phosphonobutane-1,2,4-tricarboxylic acid was used as a dispersant for alumina suspensions. Zeta potential, FTIR, effective diameter，specific
surface area and sedimentation behaviour were studied. It was found that both the phosphonyl and the carboxyl groups participated in the chemical
interaction of PBTCA with alumina. Settling experiments revealed the excellent dispersing ability of PBTCA. The fractal theory was employed
to analyse the surface morphology of sediments. It was showed that the fractal dimension value was closely related to the suspension stability.

Direct coagulation casting (DCC) is a novel-net-shape method for forming ceramic green bodies, which is based on the principle of the in-situ coagulation of a
powder suspension via a reaction-rate-controlled enzyme-catalyzed reaction after casting. Combining the rheology with the shape-forming technology of ceramic suspension,
the coagulation kinetics of silicon nitride suspension for DCC forming were investigated. The experimental results indicate that the coagulation kinetics can be successfully
studied by the dynamic relaxation experiments in terms of “coagulation time”, which provides a convenient and practicable way to research the coagulation kinetics of
ceramic suspension. After optimizing the processing conditions of the silicon nitride suspension for DCC forming, a green body with uniform, narrow and unimodal pore size distribution was prepared.

The effects of sizes and phases contents of the starting materials Si₃N₄ and AlN, YAG additive and preheating conditions on the gas-pressure sintering
behavior, phase compositions and properties of Y-α/β-sialon composites were investigated. Three stages of sintering (1700℃ for
1h, 1800℃ for 1h and 1950℃ for 1.5h) are necessary for the densification of Y-α/β-sialon composites as the reaction between Si₃N₄ and liquid phases at high temperature is minimized.
Fine AlN powder is beneficial for the densification with proper sintering schedule and embedding powder. Amount of α-sialon phase in the product
is decreased when very fine Si₃N₄ (0.3μm) is used because of increased oxygen content in the powder. No α-sialon phase was found
in the product when pure β-Si₃N₄ was used as raw material in our experiment. By adjusting the Al₂O₃ amount such as from 3.7mol% to
5.1mol%, the morphologies of the samples varies greatly. The amount of elongated grains increases obviously in the sample with YAG instead of
Y₂O₃ and Al₂O₃ as additive. Phase development study at the temperatures between 1300℃ to 1900℃ shows that YAG additive postpones the formation of α-sialon.

Carbide powders were coated with very thin alumina films by the sol-gel process. The coated powders were then
hot-pressed as a novel cutting tool material. This material possessed relatively high hardness, which led to similar wear resistant ability with ceramics. At
the same time, its bending strength and toughness were higher than that of the ceramic cutting tool materials with similar composition. As a result, these tools show
good performance in cutting high-hardness materials. SEM and TEM photographs of coated powders and fracture surface were presented as an aid to illustrate the
strengthen mechanism.

Some factors that affect the behavior of sol-gel process, such as pH value, H₂O concentration and heating temperature were investigated. TG-DTAand XRD analysised the procedure of dried gels with increasing temperature and the structure of as-calcined powders. The results indicated that the crystallizing temperature of BaNd₂Ti₅O₁₄ was 509℃ and the size of the crystallized powders calcined at 800℃ for 2h was 50nm.

The beginning temperature of chemical reaction between Ti and B₄C and the production phase after soaking 0.5h at 1600℃ were determined by DT and XRD, respectively. The mechanism of chemical reaction was studied by the diffusion couples of Ti-B₄C. It shows that the diffusion path is Ti/TiC/TiB/TiB₂/B₄C and the (TiB₂+TiC+TiB) triple phases coexist in the Ti-B₄C diffusion couples. However, there exist two phases of TiB₂ and TiC for the powders of Ti+B₄C sintered at 1600℃.

The erosion and abrasion of Sialon ceramic was studied using silicon carbide particles as
wear media. The erosion of Sialon represents the character of brittle erosion: under the high angle erosion, the erosion wear rate increases
rapidly with the increase of the erosion angle, being maximized at 90℃. The analysis of SEM indicates that the erosion mechanisms of Sialon ceramic
mainly are microcutting and surface grain spalling. In the abrasive wear of Sialon ceramic, under a higher load, there is an exponential relation between
wear loss and wear time; under a lower load, at the beginning of wear there is an incubation during which wear loss is keeping at low level, then wear
loss will increase after incubation. The incubation was discussed. By SEM analysis, the dominating wear mechanisms are plough and surface
fracture shedding.

HA/Ti composite coatings on Ti-6Al-4V substrate were successfully deposited via plasma spraying, and
then the microstructure, phase composition and mechanical properties were investigated. The results obtained indicate that the phases of HA and Ti
are well-distributed in the composite coatings. The bonding strengthes of HA/Ti composite coatings are much higher than that of HA coating,
that is explained in terms of the reduction of the mismatch of thermal expansion coefficients between coating and substrate. The value of
bonding strength of HA/Ti composite coating does not obviously vary with the immersion time in simulated body fluid. Fracture toughness and hardness
of HA/Ti composite coatings are higher than that of HA coating.

Rotating chemical vapor infiltration (RCVI) is an improved process for fabricating C/SiC composites, and it is based on chemical vapor infiltration principle.
In RCVI process, layer-by-layer of carbon cloth and deposition of matrix were done synchronously by rotating of a graphite axis, with the result that the bottle-neck
effect of gas diffusion in traditional processes was eliminated. The effect of flux and concentration of methyltrichlorosilane (MTS, CH₃SiCl₃), deposition temperature and rotational
linear velocity of carbon cloth on deposition rate of silicon-carbide matrix, and the effect of deposition temperature on structure of silicon-carbide matrix, were studied
with lots of experiments. Three different kinds of pores, which are micro-gap around filaments, macro-holes due to weaving and spaces between plies of carbon
cloth, were rapidly filled with SiC matrix at the same time. The optimal conditions for deposition are a low pressure of 5kPa, a high temperature of 1100℃,
400 mL·min^-1 and 200 m·min^-1 flow rates of H₂ and Ar, respectively, a MTS temperature of 40℃ and a 1.1～3.5mm·min^-1
rotational linear velocity of carbon cloth.

Effective reducing the charging on surface of ceramics is the key point of AES and SAM analysis in ceramic materials. After the preparation of them by
thinning, the charging sharply drops down on the surface of ceramic samples, thus opening up a new application of AES and SAM technology in the analysis
of a few tons of nm size microarea since the electron beam with a high beam energy and a small spot can be focused on the samples without obvious charging. Therefore, with a
Microlab 310-F Thermal Field Emission Scanning Auger Microprobe, the chemical composition (except for H and He elements), chemical state and structure can be
identified at about 30nm areas. In this paper, four kinds of high performance ceramic samples were discussed, ① doped Dy α-Sialon, ② doped Y, La α-Si₃N₄,
③ Al₂O₃+SiC whisker composite through nitrogen and ④ SiC matrix + C-on-BN-on-SiC multilayer fiber composite. It was observed that
Si(LVV) and Si(KLL) shift to 84eV and 1613eV respectively in kinetic energy and the former keeps on shifting to about 80eV due to the binding of Si-N-O. Four
different solid solution phases and three different intergranular phases exist in some microareas of ① sample and Si shows two or more than two kinds of binding
states in the intergranular phases of ② sample. In addition, C layer and the C-BN interlayer can be detected on the surface of C-on-BN-on-SiC multilayer
fibers pulled out from the fractured SiC matrix.

The growth process of fluoride laser crystal Nd³⁺: LiYF₄ by Bridgman method was reported. By using raw materials treated by fluoridation, and matched with the composition ratio of LiF: YF₃=51.5:48.5, a high quality fluoride laser crystal Nd³⁺: LiYF₄ with a large-size of φ25×80 mm was grown under nearly sealed conditions.

This paper introduced the preparation of stable iron-nitride magnetic fluid by vapor-liquid chemical reaction between
iron carbonyl and ammonia. The effects of experiment parameters, such as reactant proportion, reaction temperature, the type and the dosage of the surfactant on
product properties were studied in detail. X-ray diffraction(XRD), transmission electron microscope(TEM) and vibrating-sample magnetometer(VSM) were carried out
to measure the chemical structure, the crystal style and the magnetic property. The prepared magnetic fluids have high performances with respect to saturation magnetization, up to 0.134T.

Nanometer-sized quasicubic and spindle α-Fe₂O₃ particles were prepared by microwave heating from 0.2mol·L^-1Fe³⁺ salts solution. The obtained α-Fe₂O₃ particles have smaller sizes and uniform distribution by contrast with conventional heating. Inorganic ions such as H⁺, OH^- and Na⁺, can obviously affect the precipitating rate of spindle α-Fe₂O₃ and accelerate the hydrolysis of ferric ions.

The syntheses of transparent colloidal solutions of extremely small titanium dioxide particles (d=3nm) and powders (d=6.8nm) in the rutile phase were
presented. Quantum-sized effects were observed by using UV-Vis absorption spectra，reflectance spectra and differentiate absorption spectra. The amount of blue-shift
of λ_onset is greater than that of colloid titania in the anatase phase and also greater than that of theoretical prediction developed by Brus
based on effective mass approximation and tight binding approximation.

Direct copper-bonded alumina substrates were widely used in large-power applications. Cu-Cu₂O eutectic bonding of copper to Al₂O₃ was investigated in this paper. Oxygen was introduced by pre-oxidizing copper foil and it was shown that Cu-Cu₂O eutectic liquid promoted the bonding between copper and Al₂O₃ greatly. Chemical reaction happened at the solid-liquid interface and led to the formation of the binary oxide CuAlO₂, which can be observed when the specimen was prepared at 1070℃ for 60min.

The dielectric and piezoelectric properties of lead magnate niobate-lead titanite(PMNT) ceramic material in the vicinity of the morphotropic phase boundary
were investigated. The properties in the material can be improved by selecting the proper composition and sintering processing. The value of
the piezoelectric coefficient d₃₃ and the coupling factor k_t is larger than 540 pC/N and 0.50, respectively. The microstructure
of the material sintered with different time was investigated. Longer sintering time not only makes grains larger, but also makes the
growing speed of grains faster. The correlation between chemical composition, microstructure and the piezoelectric property in PMNT ceramics was discussed.

The chemical vapor deposition of diamond films on copper substrate with Ni intermediate layer was studied.
The adhesion of the diamond film on the copper substrate was improved due to the formation of a Cu-Ni eutectic between the copper and the Ni
interlayer. Scanning electron microscopy and Raman spectroscopy were used to investigate the films: The diamond films with (100) oriented diamond
particles were obtained under suitable conditions, which involved scratching carefully the substrate with diamond grits and subsequently
annealing the substrate with high temperature hydrogen plasma. The uniformity of the Cu--Ni--C--H eutectic influenced the uniformity of
the diamond film.

The optical properties of ZrO₂:CdS films were studied with absorption and fluores- cence spectra. The blue shift of band edge of CdS caused by the quantum size effect was observed. The fluorescence properties of ZrO₂:CdS films at different excitation waxrelength were studied. The weak luminescence of CdS can be observed. The influence of ZrO₂ dielectric matrix on the luminescence properties of CdS was also discussed.

In the experiment, hydroxyapatite coatings were obtained by using vacuum plasma spraying system. XRD and SEM were used to estimate the as
received coating. The results indicated that, both amorphorization and thermal decomposition of hydroxyapatite took place in the process
of plasma spraying. Amorphous phase was formed due to rapid cooling of the melted hydroxyapatite droplet. The thermal instability of hydroxyapatite
at temperature 1300～1400℃ caused a decomposition of HA powder into CaO and TCP. A rough-surfaced coating was obtained by plasma spraying. Pores and
microcracks were observed as the characteristics of as received coating. A sintering process between the splats occurred in the process, which
was caused by the degradation of thermal exchange property between coating and titanium substrate.

A series of AE spectra for "as-deposited" C₆₀ films on Si(100) substrate annealed at different temperatures were studied. C₆₀ molecules begin to decompose at 973K and result in a graphite-like carbon fragmentation. When C₆₀ film is heated to 1073K, silicon and carbon will bond to form silicon carbide.At 1123K all C₆₀ molecules will decompose. The results may take place an important role for the explanation of C₆₀ molecule promoting diamond nucleation.