Abstract:The researches on the thermal transport mechanism in carbon aerogels are reviewed. The different
thermal conductivity components and the variables affected on them are analyzed. The structures that are suitable for
using as thermal insulators are proposed. The researches on the applications of carbon aerogels in thermal protection
system are reviewed, and the challenges are discussed

Abstract:This review mainly summarized recent progress on the fabrication of non鄄oxide ceramics, such as
SiCN, BN, B(C)N,and SiN, by the non鄄aqueous sol鄄gel method, on the basis of ammonolysis reaction, aminolysis
reaction, and the carbodiimide reaction. Future prospects of the method were also discussed.

Abstract:As an advanced high temperature structural ceramics,zirconium carbide is widely used in aerospace,
cleaning energy (the fourth generation nuclear technology) and other related areas. The preparation technology of zir鄄
conium carbide powders is reviewed in detail,including direct reaction,mechanical activation,self鄄propegating high鄄
temperature synthesis,carbothermal reduction,sol鄄gel,liquid precursor,laser pyrolysis,high frequency plasma,among
others. The characteristics of the preparation techniques are detailedly analyzed.

Abstract:Zirconia aerogels has been paid great attention for its unique properties. This paper summarizes the
structure and various preparation methods of zirconia aerogels. The preparation methods include organic salt hydrolyse
method(zirconia alkoxide hydrolyse method) and inorganic salt hydrolyse method (addition of propylene oxide meth鄄
od,dispersed inorganic sol鄄gel method). The addition of propylene oxide method is one of the most potential route for
the synthesis of high performance zirconia aerogels.

Abstract:Ultra鄄high temperature ceramics (UHTCs) have become摇potential candidate materials in the fields
of future hypersonic flights and reusable launch vehicles due to their excellent physical and chemical properties in the
extreme environments. In recent years, much research focus on the preparation and properties of ZrB2 -SiC compos鄄
ites. This paper introduces the present research of fabrication process, densification behavior, and estimated the me鄄
chanical properties of zirconium diboride composites.

Abstract:The radiation and conduction coupled heat transfer processes in optical windows under aerodynamic
heating are studied in order to understand the thermal emission characteristics and the thermal protection properties. A
computational model for the coupled heat transfer in optical windows with Fresnel interfaces is established by FVM,
MCM and spectral band model. The heat transfer characteristics for a specific optical window with two SiO2 glass lay鄄
ers are numerically simulated. Results show that the glass layer under aerodynamic heating has net radiation emission
and the other layer has net radiation absorption. Radiative flux in the optical window is greater than conductive flux
except in the vicinity of the heated surface. The radiative flux in the wavelength between 2. 9 滋m and 4. 2 滋m is grea鄄
ter than in the wavelength between 0. 4 滋m and 2. 9 滋m where the radiative flux going into spacecraft interior through
the optical window has the lowest value in the visible spectrum and the highest value in the mid infrared spectrum. In
the case of the optical window total thickness unvaried, decrease in both the gas conductivity and the gas layer thick鄄
ness can effectively lower the steady state temperature of the optical window's unheated surface.

Abstract:Thermal radiative properties have significant influences on the radiative heat transfer process which be鄄
comes obvious in nanoinsulation materials at high temperature. In order to better understand the materials radiative
properties, a theoretical method based on Mie theories is presented for nanoinsulation materials containing both rein鄄
forcement fibers and opacifiers. Corresponding computer codes are developed and the thermal radiative properties are
studied theoretically for a specific nanoinsulation material. The parameters describing the radiative properties are ob鄄
tained which include the spectral extinction coefficient and scattering albedo, the Rosseland averaged extinction coeffi鄄
cient and scattering albedo, the Rosseland averaged scattering phase function etc. Results from theoretical simulation in鄄
dicate that for the wavelength studied between 3 滋m and 9.5 滋m,the material has strength extinction to thermal radia鄄
tion. The material exhibits highly scattering for thermal radiation with the wavelength between 3 滋m and 7 滋m. For
thermal radiation with the wavelength between 7 滋m and 9.5 滋m, the scattering phenomenon becomes weak with the in鄄
crease of wavelength. For thermal radiation with the wavelength of 9郾5 滋m, the material exhibits obviously absorbing.
Under the temperature between 300 K and 1 300 K,the rosseland averaged extinction coefficient of the nanoinsulation
material is greater than 50 000 m-1,and its averaged scattering albedo is greater than 0.96. The highly forward scattering
characteristic of the material results from the opacifier and the reinforcement fibers in the material have less influences.

Abstract:Aimed at a new type of cable seal structure, the finite element model of sealing buffle plate, sealing
plate, rubber plate and bolt were established. Considering the geometric nonlinear, boundary nonlinear and material
nonlinear, the stress and strain of the structure under the action of pressure and bolt load were calculated. Moreover,
the stiffness of the structure was investigated in the paper. The results show that the local stiffness of cable seal struc鄄
ture is yield and the material should be changed; Moreover, the sealing of the structure is finer, which is proved rea鄄
sonable by the sealing experiment.

Abstract:Flexible fiber reinforced silica aerogel composites for thermal insulators were prepared by ammonia鄄
catalyzed one鄄step sol鄄gel process, using tetraethoxysilane as precursor, high silica fiber as reinforcement. The highest
specific surface area (SSA) can be obtained in an aerogel derived from the sol with pH=7. The SSA decreases with
increasing the water molar ratio, while it increases with increasing the ethanol molar ratio. When the molar ratio of
ethanol/ tetraethoxysilane is higher than 10, the SSA only increases mildly with increasing the ethanol ratio. The ther鄄
mal conductivity of the high silica fiber鄄reinforced high SSA aerogel composites is 0. 031 W/ (m·K )[0. 044 W/ (m·
K )for the high silica fiber matrix]. The flexible aerogel composites are easy鄄to鄄install and are very suitable for insula鄄
tions on large surfaces and complex shapes.

Abstract:RF aerogels, which process good nano-network structure, were prepared by resorcinol and formalde鄄
hyde diluted in deionized water in the presence of sodium carbonate as catalyst, followed by ambient drying. The struc鄄
ture of the porous organic aerogels was investigated by SEM and the measurement of pore size distribution. The special
surface area was determined with BET. The results showed that the structure of organic aerogels are controlled from mi鄄
cropore to macropore by changing the concentration of catalyst. The samples prepared by ambient drying have low densi鄄
ty of 321 to 632 kg/ m3,and the sample density is 428 kg/ m3 with specific surface area of 188 m2 / g.

Abstract:Porous Si3 N4 ceramics were prepared by gel casting using agarose additives. By changing the solid
content of the slurries, porous silicon nitride ceramics with different porosities, 茁-Si3 N4 contents, and mechanical
properties were obtained. When solid contents changed from 35vol% to 45vol%, the porosities decreased from
57郾6% to 40. 8%, while the fracture strength increased from 96 MPa to 178 MPa. Many fibrous 茁-Si3 N4 grains
grown from the internal wall of the round pores, the growth mechanisms of fibrous 茁-Si3 N4 grains resulted from the
synergy of solution鄄diffusion鄄reprecipitation and vapor鄄liquid鄄solid. Both elongated 茁-Si3N4 grains and suitable interfa鄄
cial bonding strength contributes to the high fracture strength.

Abstract:This paper analyzed the causation of distortion of resin composites after long time ablation. And stud鄄
ied the property of the quartz fiber reinforced phenolic resin at different temperature. It is shown that the thermal
stress is the dominating reason causing the distortion of resin composites after long time ablation.

Abstract:For improving heat鄄obstructive effect and avoiding brittleness from increasing phenolic resin, a novel
reformative method was thought out and carried into execution. A kind of pyrolysis fiber showed the similar decomposi鄄
tion characteristics as phenolic resin. A typical sample was produced according to the modified principle and tested.
Arc heated wind tunnel experimental results indicated that the back temperature of 20 mm new composite was lower a鄄
bout 40益than high silicon/ phenolic under the same test condition (The highest surface temperature was 1 300益and
the total heating time was 600 s). The new composite showed excellent heat鄄obstructive effect and the results were
consistent with the original objective. The novel reformative method was perspective on improving the heat鄄obstructive
effect

Abstract:The phenolic resin was modified by polyamide for improving the toughness of phenolic foam,and was
foamed by chemical method. The effect of polyamide on the properties of phenolic resin and foam was studied with the
analytical methods including DSC, gel鄄time,bending strength,and SEM. The results showed that the co鄄curing between
polyamide and phenolic resin happened,the reactivity of phenolic resin decreased with the increasing of polyamide,the
polyamide improved the toughness of phenolic foam effectively,the bending strength of phenolic foam presented the trend
of up first and down second with the increasing of polyamide,and attained the most enhancing about 81% than the un鄄
modified when the content is 10wt%,the bubble structure of phenolic foam is improved from the SEM images by adding
a little of polyamide,when adding 10wt% it is best and the bubble size is symmetrical in which the average diameter is
about 400 滋m.

Abstract:The damage effects of 1. 4 MeV electron irradiation on several epoxy resins cured by 4,4忆鄄diaminodi鄄
phenyl methane were investigated. The results show that the epoxy resins are subjected to discoloration,weight loss,
cracking and degradation of mechanical properties when exposed to high鄄energy electron irradiation. The degradation
varies with absorbed dose and the chemical structure of epoxy resins. Evaluated from the extent of cracking and com鄄
pressive strength reduction,all the epoxy systems studied in this work,including diglycidyl ether of bisphenol A
(DGEBA), N,N,N忆,N忆-tetraglycidyl-4,4忆鄄diaminodiphenyl methane (TGDDM),triglycidylether of para鄄aminophe鄄
nol (TGPAP),the DGEBA/ TGDDM and DGEBA/ TGPAP blends are tolerant to the absorbed dose of 106 Gy. Only the
DGEBA/ TGPAP blends, which have a moderate crosslinking density,can withstand the absorbed dose of 107 Gy. The
order of radiation resistance of the epoxy resins is revealed to be DGEBA/ TGPAP > DGEBA/ TGDDM >TGPAP抑TG鄄
DDM>DGEBA. An increase in compressive modulus induced by irradiation implies a crosslinking mechanism domi鄄
nates the degradation of epoxy resins,which is confirmed by the DMA and DSC measurements

Abstract:Novel epoxy matrix resins have been prepared with the tetraglycidyl meta鄄xylenediamine (TGMXDA)
and bisphenol F epoxy ( DGEBF) as the matrix and the aromatic diamines, 4,4忆鄄bis[(4鄄amino鄄2鄄trifluoromethyl)
phenoxy]biphenyl (6FBAB) and 3,3忆鄄diamino鄄diphenylsulfone (DDS) as the hardeners. The effects of the chemical
structures and formulations of epoxy resins and the diamine hardeners on the properties of the cured epoxy compounds
were systemically investigated. The results indicated that the TGMXDA-DGEBF/ DDS-6FBAB epoxy systems exhibi鄄
ted good toughness with the tensile strengths exceeded 101 MPa,impact strengths higher than 20 kJ/ m2,and elonga鄄
tions at break over 6. 0%. Meanwhile, the cures epoxy showed good thermal stability up to 330益in nitrogen.

Abstract:The smoke density of laminates made of flame鄄retardant epoxy/ glass fiber prepreg have been meas鄄
ured by NBS chamber. The effect of smoke density of laminates has been investigated. The results indicate that smoke
density relates with resin content of composite, bromine鄄antimony cooperative flame鄄resistor, dosage of hardener, and
epoxy value of the resin

Abstract:A series of phenylethynyl鄄terminated polyphenylquinoxalines (PEPPQs) (PPQ-1 to PPQ-4) were
prepared with 4鄄phenylethynylbenzil (PEBZ) as the terminator and 9,9-bis(4鄄benziloxyphenyl) fluorene (FLTK) and
3,3忆,4,4忆鄄tetraaminobiphenyl (BPTA) as the monomers. The designed molecular weights are 2 500 for PPQ-1, 5 000
for PPQ-2, 10 000 for PPQ-3, and 20 000 for PPQ-4. The rheological measurements show that PPQ-1 and PPQ-2 ex鄄
hibited good processability with the lowest melting viscosities of 21 Pa·s and 568 Pa·s at about 350益, respectively.
Cured PPQ-1 and PPQ-2 samples are prepared via the thermally molding process. The cured PEPPQs show high glass
transition temperatures of 338益for PPQ-1 and 325益for PPQ-2, respectively. The cured PEPPQs show good thermal
stability with the 5% weight loss temperatures higher than 550益and residual weight ratio higher than 60% at 750益.
Cured PPQ-2 resin exhibit good mechanical properties with the tensile and flexural strengths of 88 MPa and 125 MPa,
respectively. The elongation at break of the resin reached 7.6%.

Abstract:The viscosity of solid and liquid polycarbosilanes with different molecular weight were investigated
based on GPC and Rheometer analysis. And the relationship between molecular weight,soft temperature and viscosity
were established. The ceramic yields of these polycarbosilanes were reported based on TGA. The results indicated
LPCS had lower viscosity (under 200 mPa·s) at room temperature and higher ceramic yields (77%, N2 ), whereas
the molten solid PCS had viscosity of 500 mPa·s only above 200益so that LPCS is more suitable for room temperature
PIP than PCS to make ceramic matrix composites

Abstract:Dense Al-Y-Si-O-N ceramic coating on the surface of porous Si3N4 was fabricated with oxides of
Al2O3 -Y2O3 -SiO2 sol and Si3N4 of porous substrate using sol鄄gel method. Microstructure and properties of ceramic
coating at the different temperatures were studied mainly. Phase composition and element component was analysed by
XRD pattern and EDS,respectively, and microscopic morphology of surface and cross鄄section of coating was observed
by the SEM. The ceramic coating is densified when the coating is sintered at 1 400益, and phase compositions of
coating are consisted of 茁鄄sialon, Si2ON, SiO2 and amorphous phase. The results show that the water absorption of
porous Si3N4 is decreased from 32. 8% to 90%, and the flexural strength of porous Si3N4 is increased from 2. 1% to
25. 9%.

Abstract:RF thermal plasma had been employed to prepare ZrB2 and ZrC ultra鄄fine powder materials based on
thermodynamic calculation. The products were characterized by XRD, FESEM, and Hall flowmeter. Results revealed
that high鄄purity ZrB2 and ZrC powders with an average diameter less than 100 nm could be obtained, and the apparent
density of ZrB2 and ZrC was 0.71 g/ mL and 0.46 g/ mL. The production capability in the laboratory can reach 500 g/
h.

Abstract:The oxidation behavior of SiBCN ceramics, derived from pyrolysis of polymeric precursor, was inves鄄
tigated by oxidizing the SiBCN ceramics at 1 200益under air for different time. As a reference, SiCN ceramic was
studied using the same process. The results show that after oxidation for 10 h, the weight gain of SiBCN is only
0郾35% and the ceramic keeps its original morphology without cracks. Whereas, the oxidation of SiCN results in a
weight gain of 3. 10% and cracks. The elemental composition of the sample surface is mainly SiO2 for SiBCN and SiOx
(x<2) for SiCN ceramics, respectively

Abstract:Si2 N2 O was prepared by carbothermal reduction and nitridation of SiO2 at 1 500益. The catalytic
effect and mechanism of Fe2O3 on synthesis of Si2N2O were investigated by XRD and thermogravimetry. Fe2O3 had a
remarkable catalytic effect on synthesis of Si2N2O. A 100% conversion ratio of SiO2 could be achieved when adding a
little Fe2O3. The catalytic mechanism of Fe2O3 could be concluded as:on the one hand,the Fe2 O3 can be reduced to
nanosized Fe by C,which may form Fe-Si liquid with Si. The Fe-Si liquid can dissolve SiO2 and C particles and pro鄄
mote formation of the intermediate phase SiOC at a lower temperature,leading to a significantly decrease of the starting
temperature of carbothermal reduction. On the other hand,the CO2 can react with Fe-Si liquid to form SiO and CO,
which may enhance the reaction rate of carbothermal reduction.

Abstract:The pyrolysis characteristic of phenolic resin has been investigated by means of thermogravimetric a鄄
nalysis and TG鄄MS analysis. Models of the pyrolysis kinetics were derived using the coats鄄redfern integral method.
The results show that the pyrolysis reactions of phenolic resin have two types: reaction of chain breaking ( <600益in
the low temperature region) and reaction of dehydrogenation (600 to 800益in the high temperature region). The py鄄
rolysis of phenolic resin can be described by first鄄order kinetics equations in both temperature regions. Different heat鄄
ing rates do not show evident influence on the active energy of two pyrolysis reactions.

Abstract:A study of image processing and data analysis of SEM micrographs of T300,GCF-1 and GCF-2 car鄄
bon fiber samples was described in this paper. A Matlab program compiled in this study was employed to study the sec鄄
tion patterns of carbon fibers. The diameter, roundness,quantity and scale of grooves on carbon fiber surface can be
obtained by image processing and data analysis method established in this research. A Weibull distribution of the
grooves on the surface of all three kinds of CF samples was discovered. The evolution of the surface properties during
heat treatment up to 2 500益showed the similarity of the CF爷s structure. The roundness of T300 carbon fiber is less
than GCF-1 and GCF-2. By using this method,the physical properties of carbon fiber爷s surface can be quantitatively
characterized.

Abstract:X鄄ray diffraction method ( XRD) includes two tasks:qualitative and quantitative analysis. The three
ratios of(Si +TiO2)are analyzed by XRD,the quantitative analysis data were obtained from the rietveld analyses . The
results show that the compositions are close to the real ratio of the samples. The Rietveld methord is reliable for the
quantitative phase analysis. and the relative standard deviation was 依2% (n = 3). The results demonstrate that X鄄ray
powder diffraction combining with the rietveld refinement method is an accurate, convenient and speed鄄up method.