Space High Temperature In Situ Observation Instrument “SHITISOI” was dedicated to visualize and record the
whole KNbO₃ cellular growth process in Li₂B₄O₇ flux. The dependence of buoyancy and surface tension convections on the cellular
growth was studied. In space, the streamlines of the steady surface tension convections in the Li₂B₄O₇ flux were observed. The steady
convections occur in the form of a mirror symmetric pattern. Due to the surface tension convection, the KNbO_3 grains grow and fill the whole
solution homogeneously. On the ground, the buoyancy drive flow in direction opposite to that of surface tension flow can reduce the cellular growth
and the distribution of KNbO₃ solute grains is inhomogeneous in the Li₂B₄O₇ flux. A theoretical model of cellular growth was also
accounted. A pivotal feature in this model is the initiation of the surface tension convection on the interface of KNbO₃ grain. This is initiated
by KNbO₃ solute surface tension gradient which is caused by less rapid diffusion of KNbO₃ solutes. Direct comparison of the model predictions
and experimental observed phenomena demonstrates the predictive capability of this model.

There are many kinds of sulphide crystals in the nature. Their crystal structures are complicated in which
S ions exist in the form of S^2- and S₂^2-. Of them, the growth habit of some crystals is not explained successfully. In this paper, the growth habit of
MoS₂，ZnS，CuFeS₂ and PbS were reasonably explained in terms of the coordination polyhedron rule. The growth habit of MoS₂ is hexagonal platy {0001}. The
relationship between different crystal faces in growth rate is: V_<0001><V_<1010>; the growth habit of the CuFeS₂ and ZnS
crystals is a tetrahedra. The relationship between different crystal faces in growth rate is: V_<111>>V_<001>>V_<111>；the growth habit of
PbS crystal is an octahedron {111}, its habit change is a cube.

The phase equilibrium in pseudo-binary system LiF-CaAlF₅ was studied by means of thermal analysis (DTA) and X-ray diffraction (XRD). A congruent melting compound LiCaAlF₆ with melting point of 814℃ produces at the composition of LiF:CaAlF₅=1:1. There exist two eutectic systems from LiF to LiCaAlF₆ and from LiCaAlF₆ to CaAlF₅ with eutectic temperatures of 705℃ and 781℃ respectively. According to the proposed phase diagram, fluoride laser crystal Cr³⁺:LiCaAlF₆ was grown by Bridgman method.

By analyzing the potential of an octahedral alkali cation, the varying of the potential of alkali cation, whose position is in three different directions of [111], [110] and [100] was calculated.
The results show that off-center sites in K₃C₆₀ crystal actually exist in these three directions. The deviations from the center are different to be 0.98A, 0.78A,
0.56A respectively in [111], [110] and [100] directions. The potential at off-center site in [111] direction is the lowest, --508.59meV. The existence of off-center sites owes
to the short range interaction of alkali, especially the interaction between alkali and C₆₀ anions. The most important is that the site corresponding to the lowest
potential point is not at the symmetric center. The reason of the different deviations in these three directions is the different densities of C₆₀ anion in the
corresponding crystal planes.

The synthesis process of KDP material was analyzed and phosphite was found existing in the growth solution.
In the crystal growth experiments, significant extension was observed at low dopant concentration, but at higher concentration, the growth rate of the
whole crystal decreased with no significant change of the habit. The inhibiting effects of phosphite and other anionic ions on the
growth of pyramidal face was discussed. Rapid growth experiments was carried out with purified material and an averaged growth rate of 13.7mm/day was obtained.
It was proposed that the purity of the materials is the key factor for rapid growth of KDP crystals.

Luminescence centers were created in the CsI host crystals by annealing of Pb-doped crystals at 400℃ in air. It was found that the excitation spectra of these luminescence centers are coincided
well with the excitation absorption of a series of compounds in the Cs-Pb-I system, which indicates that they are attributed to the creation of CsPbI₃, CsPbI₆
and other aggregates in the annealing process. The emission spectra of Pb:CsI crystals were measured in the 10-30K temperature range by 360nm and 410nm excitation respectively.
The relative intensities of emission bands depend strongly on annealing time, which implies that the creation and transformation of various Pb-based aggregates in Pb:CsI
crystals tend to active around 400℃ annealing temperature.

The preparation of high purity raw materials is the foremost section in fabrication of high quality optical fibers. The material of silver halide was ultrapurified by horizontal zone
melting purification in Cl₂ atmosphere. Measurement results show that infrared absorbance will decrease as wavenumber increases at 800～4000cm^-1
after the ultrapurification, and the absorption coefficient of silver halide preform crystal by CO₂ laser calorimeter is less than 5×10^-4cm^-1
at 10.6μm. The absorption coefficient decreases two order of magnitude after ultrapurification. The optical fiber loss is 0.3～0.5 dB/m.

The surface properties of two different kinds of silicon carbide were studied. Though they have similar distribution of particle size, but their slurries show different rheological properties.Adding PEI into slurry of SiC-1 as a dispersant to form stable slurry is needed and the maximum solid content of SiC-1 slurry can reach as high as 40vol%. Another powder named as SiC-2 can reach its high solid content as much as 55vol% only by adjusting pH values.

The rheological properties of TiO₂/water suspensions were examined by means of Brabender rheometer
with rheological method. It was observed that yield stress and steady shear viscosity of TiO₂/water suspensions with narrow PSD is higher than those
of TiO₂/water suspensions with wide PSD. When volume fraction of particle Φ is very low, the suspension exhibits Newtonian behavior. All tested pastes
exhibit shear-thinning behavior when volume fraction of particle Φ is higher than a certain value; when Φ beyond a critical value, the pastes have yield
stress and exhibit more obvious shear-thinning behavior. The shear viscosity of TiO₂/water suspensions follows a generalized Quemada model and parameters
were obtained by simulating. When the temperature is below 40℃, the shear viscosity and yield stress decrease with the increasing of temperature;
when the temperature is higher than 40℃, yield stress increases with the increasing of temperature while shear viscosity exhibits complex
behavior. The temperature dependence of shear viscosity and yield stress can be explained by collision theory of fine particles in suspending mediums.

Aluminium titanate is an excellent inorganic non-metal material due to its high melting point
and low expansion. In order to improve its strength and to suppress its thermal decomposition, additives are frequently introduced into
it. In this paper, the effect of a single additive or compound additives on the thermal expansion coefficient of Al₂TiO₅ was investigated.
The results show that the addition of some rare-earth oxide can greatly reduce the thermal expansion coefficient of Al₂TiO₅. For example, the
addition of 1～4mol% CeO₂ or 2mol% La₂O₃ makes its expansion coefficient come near zero. That gives a new approach in the development of materials with no thermal expansion. It is
indicated that there is no change in the expansion coefficient of Al₂TiO₅ by adding 1～4mol% Fe₂O₃ in it. The addition of SiO₂
in Al₂TiO₅ containing 4mol% Fe₂O₃ increases its expansion coefficient while the addition of another rare-earth oxide decreases
the expansion coefficient. Proper batching of three additives can adjust the expansion coefficient of Al₂TiO₅ to minimum. The addition
of the compound additives may be very significant for improving the properties of Al₂TiO₅.

The microstructures of Ln-α-Sialon-AlN-polytypoid(Ln=Y, Y+Sm and Sm)dual-phase ceramics, with a overall composition 90wt%α-Sialon(m=1, n=1.7)+10wt%12H,
hot-pressed in the range of 1650～1800℃, were studied by SEM. The results show that in all compositions, α-Sialon grains are small at 1650℃ and part of them exhibits elongated morphology at 1800℃.
The morphologies of α-Sialon grains are slightly varied with different rare-earth elements. Sm-α-Sialon exhibites the finest microstructures
with the aspect ratio of elongated grains of 7～9. In Y-composition, α-Sialon is coarsest grains with the aspect ratio of elongated grains of 2～3. There is
agglomerated AlN-polytypoid in all compositions, and which shows fiber-like morphology. The extent of non-uniform distribution of AlN-polytypoids in these
composite ceramics decreases in the sequence of Y-, Y+Sm- and Sm-composition. These differences of microstructure may be attributed to the effect of different
rare-earth elements on the formation kinetics of Ln-α-Sialon-AlN-polytypoid dual-phase ceramics.

The bulk samples of nanophase PbF₂(n-PbF₂) with the clean interfaces were prepared by using an inert gas evaporation and in situ compacting technique. The phase constitution and ionic conductivity were studied by XRD, DSC and complex impedance spectra. The results show that the ionic conductivity of n-PbF₂ is rather higher than that of coarse-grained PbF₂. The temperature of phase transition from α-phase to β-phase for n-PbF₂ drops about 30℃ compared with that of coaxse-grained PbF₂.

Sr_1-xBi_xFeO_3-δ (x≤0.50) series oxide ionic/electronic conductors were prepared through citrate gel precursors. The product was characterized by means of XRD, IR, TG, DTA and ac impedance techniques. Pure perovskite-type phase was formed after the gel combusted and calcined at 800℃, and had an orthorhombic structure similar to that of SrFeO₃. Although the density of the product calcined at 85O"C remained 97% theoretical value, an extreme conductivity of 3.6Scm-1 was found at 400℃.

The impedance characteristics of thick films gas sensors were investigated by measuring the dependence
of the reactance component on frequency in testing gas. Using the variations of reactance with the concentration of gasoline or alcohol
gas to define the sensitivity of gas sensors, a new method greatly improving the sensitivity and selectivity of gas sensors compared
with the traditional d.c. method was proposed. Such improvements maybe come from that the complex impedance analysis detects not
only the change of grain boundary resistance but also the change of grain boundary capacitance with the gas adsorption and/or
desorption on the surfaces of sensors.

The authers studied the effects of the frequency and temperature on the TiO₂-K₂O-LiZnVO₄ ceramic thin film elements’ humidity
sensing characteristics. During low rh range, the impedance of the elements decreases as the frequency or temperature increases, the humidity sensitivity decreases obviously
as the frequency increases or temperature decreases, and platforms appeare at the humidity sensing characteristic curves. During high rh range, however, the effects of
the frequency and temperature can be ignored, and the characteristic curves present excellent linearity. The polarization within the ceramic thin films was analyzed.
The polarization causes the insensitivity of micro-capacitance versus rh at low rh and low temperature. Consequently, the mechanism of how the polarization within the
ceramics resulted in the effects of frequency and temperature on the elements’ characteristics was interpreted in detail.

The processing and the properties of porous hydroxyapatite ceramics were studied. Carbon powders with three different sizes were adopted to be pore-making
agent. HAP ceramics with porosity 30%～45%, bending strength >10MPa and pore diameter <200μm can be obtained. The results showed that porosity
firstly decreased and then increased with soaking time, while the bending strength increased continually. The pore size and distribution of the specimen can be
effectively controlled by strictly varying the size distribution of carbon powders. XRD and SEM were carried out to characterize phases and microstructure of the specimen.

Al₂O₃/AlB₁₂ composite powders were produced by self-propagation high-temperature synthesis (SHS) employing Al and
B₂O₃ as initial reactants. The effects of combustion conditions on the characteristics of the powders were discussed. The results show that, Al₂O₃
has an average particle size of 3～4μm , while the size of AlB₁₂ is in the submicron range. The composite powders have an average specific surface of
～1 m²/g. Impurities of B₂O₃ and 9Al₂O₃.2B₂O₃ can be observed at the surface of the products because of the evaporization and condensation of B₂O₃.
By decrease the argon pressure in the reactor, Al₂O₃/AlB₁₂ powders of high purity can be obtained. The adiabatic temperature of the reaction 13Al+6B₂O₃=6Al₂O₃+AlB₁₂
obtained from thermodynamic calculations is significantly higher than the measured combustion temperature.

The friction and wear properties of O -Sialon-ZrO₂-SiC composite were studied at room temperature and 600℃. Results show that the wear rate of O -Sialon-ZrO₂-SiC is much less than that of stainless steel at the testing condition, and main wear mechanism of the unlubricated friction is adhesive wear. It also indicates that the fractals dimension is related to the abrasion,the farger the fractals dimension, the greater the abrasion, the fractals dimension of wear ranges from 1.26 to 1.38.

Chemical uniform, high-purity spray-grade zirconia powders doped with variable ratios of yttria for
ceramic thermal barrier coatings were prepared by an internal gelation process. Both the morphology and particle size of the powders can be
controlled by varying the emulsification conditions. Scanning electron microscopic and optical microscopic observations revealed the materials
thus obtained to have a predominantly spherical morphology and the requisite size distribution (5～50μm). The dense, calcined
micro-spheres showed good flowability. Differential Thermal Analysis (DTA) of 4.7mol% Y₂O₃-ZrO₂ powders (dried at 80℃) indicated that m→’ transformation was happened at 468℃.
X-ray diffraction results showed that the crystalline phase of such powders after calcination at 800℃ was 100% nontransformable tetragonal.

The way to calculate the micro-pore-size distribution measured by Bubble-Point method was improved on the basis of the existent Graphical Solution. The new way avoids the complexity in the process of Graphical Solution, and can directly adopt the data measured in experiments to caJculate the pore-size distribution. Due to considered gas expansion effect, it makes the calculation most likely represent the real situation, and it can be easily processed by computers.

CeO₂ films were deposited by pulsed laser ablation on stainless steel substrates at room temperature
with the Ar⁺ ion beam assistance. The results show that when the CeO₂ films are deposited directly on the stainless steel substrates,
the desired (001)-normal textured films achieved, but there is no evidence for alignment of in-plane crystal axes. Further experimental results
indicate that CeO₂/YSZ(Yttria-Stabilized Zirconia)/stainless steel films deposited under the same conditions are not only normal
orientation to the substrate’s surface, but also highly in-plane textured.

Based on the deposition of titanium films on Si₃N₄ surface by molten salt reactions, the wetting behavior of a liquid CuAg eutectic
alloy on the titanium metallized Si₃N₄ was studied, it was found that, the metallized sample can be fully wetted by the eutectic
alloy. Based on this result, the joining of metallized Si₃N₄ to Si₃N₄ was successfully obtained and the joining technique
was systematically studied. TEM observation on the interfacial structure of the joints found that Ti-Cu-Si-N phases widely existed
at the interface and their possible effects on the shear strength of the joints were also discussed.

The quality of silicon carbide coating is the key factor for the utilization of carbon-carbon
composites as thermal structural materials. In order to optimize and control the deposit process, a neural network(NN) model for SiC-CVD
process was developed. The outputs of NN model were found to be best fit with the sample data’s (<0.35%). With the help of the NN model, a series of predictions about the deposit condition-results were made.
Finally, the predication about the influence of Ar on the deposit rate predicted by ANN model was identical well with the experimental
results, which shows that the model established by ANN can mirror the parameters-results relationships and inner regularity in the
SiC-CVD process.

The BAS glass-ceramic composites reinforced with different volume fractions of SiC whiskers were
successfully studied by a hot-pressing method. The results show that the BAS matrix is composed of BaAl₂Si₂O₈ and mullite. The incorporation of
SiC whiskers can significantly increase the flexural strength and fracture toughness of BAS glass-ceramics. The flexural strength
and fracture strength of 30vol%SiC_w/BAS composites can increase 128% and 190% compared to the unreinforced BAS matrix. The main toughening mechanisms are crack deflection, whisker pullout
and bridging. The results of TEM observations show that SiC whiskers are directly bonded to the BAS matrix grains with no interfacial glass
layer or reaction layer. In addition, the BAS composites also have good elevated temperature mechanical properties.

TiO₂ was doped in α-Fe₂O₃-K₂O composite system by a stearic acid-gel method. Phase composition，grain size，lattice distortion，specific
surface area，porosity and thermal stability of TiO₂-doped α-Fe₂O₃-K₂O nanometer-sized ceramics were investigated by X-ray diffraction，BET specific surface absorption and Archimede replacement water methods. The
results show that doping of a little amount of TiO₂ restrains the formation of KFe₁₁O₁₇ and β-K₂O，retards the growth of α-Fe₂O₃
grain，makes α-Fe₂O₃ lattice distortion，improves its thermal stability and keeps its phase structure of corundum as α-Fe₂O₃. Furthermore?，the relationship between TiO₂-doped amount and inner electrical resistance?，resistance-humidity characteristic and humidity hysteresis of the various
TiO₂-doped α-Fe₂O₃-K₂O system were also studied. It shows that K⁺ possibly more dispersedly exists in the amorphous surface shell layer of
α-Fe₂O₃ after doping TiO₂，and that is the main reason of humidity hysteresis being decreased.

For Studying higy-property phase shifter materials in a phase array antenna of autotrack synchronous communication
satellites, lithium ferrite Li_0.625Zn_0.1Ti_0.25Sn_0.1Fe_1.925O₄ was prepared by using a standard ceramic flowing oxygen sintering technique
and adding some benificial materials such as MnCO₃, Bi₂O₃ etc. The microwave properties of ferrite phase shifter materials Li_0.5(1-y)Zn_yFe_2.5(1-0.2y)O₄
were discussed. The measured results show that lithium ferrite Li_0.625Zn_0.1Ti_0.25Sn_0.1Fe_1.925O₄ possesses high Curie temperature and low dielectric loss.

Single-phase polycrystalline samples of La_0.5Ca_0.5-xBa_xMnO₃ (0.1≤ x≤0.5) were fabricated
by the solid state reaction method. With increasing the content of Ba doping, the structural transition occurs from cubic to orthorhombic.
The measurement of resistance as a function of temperature under zero field shows that the samples of lower doping behave a semiconducting
behavior in the whole studied temperature range, and a transition from semiconducting to metallic states appears in the samples x≥0.14. The
transition moves toward the high temperature region with increasing the doping content. The role of Ba doping on the Ca sites was discussed on
the basis of analyzing the experimental data.

The behavior and activation energy of the grain growth of the nano Y-TZP materials during pressureless sintering, hot-pressing and SPS were analyzed. It was found
that from 1100℃ to 1300℃, the grain growth behaviour for the three sintering methods is different. When sintered by hot-pressing and SPS, the grain
grows faster than that by pressureless sintering. These phenomena can be partly explained by the activation energy of the grain growth. The activation energy
of the grain growth during pressureless sintering is about 300kJ/mol. During hot-pressing, the activation energy is less than that during pressureless sintering
because of the promoting of the applied stress on the diffusion. During SPS processing, the surfaces of particles are activated by pulsed current, so the activation energy
is significantly decreased.

TiB₂ ceramics with Y₂O₃-Al₂O₃ as sintering aids were fabricated by hot-pressing. The effects of sintering temperature, holding time, and crystallization
annealing on microstructure and mechanical properties were investigated. The experimental results show that the flexural strength and fracture toughness of TiB₂ ceramics
decrease and the weight loss increases with sintering temperature rising up; with holding time prolonged, the uniformity of microstructure decreases and
this is disadvantageous to the mechanical properties. The grain diameter has a significant influence on the mechanical properties of TiB₂ ceramics. The
crystallization annealing can result in YAG phase from grain boundaries and enhance the flexural strength at high temperature of TiB₂ ceramics.

The stabilizing effect of mullite on aluminium titanate was studied in detail through XRD, RPD,
SEM and EDS. The sintering temperature was found to affect the stability of aluminium titanate. The content and the variety of mullite, as well
as annealing time, have influence on the composites. In addition, the mechanism of mullite suppressing the thermal decomposition of aluminium
titanate was discussed. Solid solution and mullite grain can suppress the grain of aluminium titanate, which results in the improvement on the
stability of aluminium titanate.

Electrokinetic behavior of hydrophobic aluminium nitride (AlN) powder was studied by zeta potential and particle size measurement in aqueous suspension by introducing different dispersants. As a result, pH values and the types of dispersants affect the surface charge and the particle dispersion of hydrophobic AlN suspension. NH4PA, arnmonium poly(acrylic acid), is an available dispersant for aqueous tape casting of hydrophobic AlN powder, proper addition of which can lead to well dispersed hydrophobic AlN suspension.

In the present study, particulate suspensions of nanosized(particle size less than 10nm) anatase and rutile TiO₂ under UV irradiation in a loop
photoreactor catalyzed the oxidation of a typical organic contaminant: phenol. Both nanosized anatase and rutile TiO₂ have a much higher photocatalytic
activity than bulk TiO₂ (particle size more than 100nm), however, anatase shows a higher selectivity for complete mineralization: the concentration of
p-quinone as intermediate of this photocatalytic reaction is at lower level than those of rutile. Species adsorbed by titanium dioxide such as H₂O and OH
play a significant role in the photodegradation of phenol as well as particle size . With the decrement of particle size especially less than 15nm,
the photocatalytic activity of TiO₂ increases dynamically.

The polycrystalline NbN/TaN nano-multilayer films were grown on the substrates of stainless steel
by reactive magnetron sputtering. The microstructures and microhardness of the nano-multilayer films were studied by X-ray diffraction (XRD),
transmission electron microscopy (TEM) and microhardness tester. The results show that the NbN layers are cubic crystal structure and TaN layers are
hexagonal in the NbN/TaN multilayer films. NbN/TaN nano-multilayer films have superhardness effects with a modulation period from 2.3nm to 17.0nm.
The maximum hardness HK is 51.0GPa.

The diffuse phase transition of PZN-PZ-PT solid solution near the morphotropic boundary was reported. The effects of PbZrO₃ on the diffuse phase transition was carefully studied. The results show that the diffuse phase transition of PZN-PZ-PT will be enhanced with the increase of PbZrO₃.

SiO₂ doped ZrO₂ buffer layers were successfully prepared by a sol-gel technique using zirconyl
chloride octahydrate ZrOCl₂·8H₂O as the precursor on stainless steel and a gold film was deposited on the buffer layer by a vacuum evaporation
deposition method. XRD, FTIR, SEM and AES measurements were used to investigate the performance of the layers as well as the physical and
chemical changes after annealing. The results show that tetragonal ZrO₂ buffer layers possess a preferential orientation at the (200)
crystal plane due to the influence of stainless steel substrate. And there is some interdiffusion at the interface of buffer layer and
substrate, which improves the adhesion of ZrO₂ layer and stainless steel. The measurement of normal emittance(ε) of Au-ZrO₂-SS
before and after 850℃ heat treatment indicates that ZrO₂ buffer layers can effectively suppress the interdiffusion of the gold film
and the substrate.

nansparent TiO₂ thin films were prepared by a liquid phase deposition method. The morphology, structure and the change of hydrophilicities under UV illumination of as-prepared films were studied. The result shows that thus prepared films axe dense and uniform, and exhibit a similar hydrophilicity whether the films are annealed or not. Their hydrophilicities are all increased by UV illumination. The films annealed can be entirely wetted by water after UV illumination for a certain time.