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The effect of tempering time on the microstructure and mechanical properties of SA738 Gr.B nuclear power steel was studied using SEM, TEM and thermodynamic software, and its precipitation and microstructure evolution during tempering were clarified. The results showed that SA738 Gr.B nuclear power steel has better comprehensive mechanical properties after tempering at 650 °C for 1h. With the extension of the tempering time, M3C transformed into M23C6 with increasing size, which affected the yield strength and impact energy. When the tempering time is 8h ~ 10h, due to the transformation of M3C to M23C6, the composition of matrix around the carbide changed, causing the temperature of Ac1 dropped, forming twin-martensite which deteriorated the impact toughness of the steel.

It is impossible to study the relationship between water damage and voidage of asphalt pavement because the voidage of pavement core sample cannot be determined accurately. Based on the industrial computed tomography (CT) scanning technology for core samples of real void fraction measurement, dynamic water flushing apparatus to water damage damage of core samples, the CT scan void fraction and destruction after the relationship between splitting strength and CPN rutting depth of core samples, respectively, set up different lanes of void fraction and cleavage strength and the fitting formula of rut depth.

The microstructure and cellular transition characteristics of an intermetallic Ti-42Al-3Nb-1Mo-0.1B (at.%) alloy were investigated. The as-cast microstructure of the alloy is mainly composed of (α2+γ) lamellar structure and (β+γ) mixture structure, which distributes along the boundaries of the lamellar colonies. In order to study the phase transformation of lamellar structure at aging temperature, a two-step heat treatment was carried out. After the first step of annealing treatment at 1,260 °C, the microstructure with relatively finer lamellar space and (γ+β/B2) mixture structure is obtained. Aging treatment, as the second heat treatment step, has significant influence on the microstructure, attributing to a cellular reaction of α2+γ→ γ+β. With the increase of aging temperature, the (α2+γ) lamellar structure continues to dissolve, whereas the contents of both the equiaxed γ and β/B2 grains continuously increase. Besides, the orientation of lamellae α2, equiaxed γ and equiaxed β/B2 in the cellular transition region follows a specific relationship of {0–11}ββ//{0001}α2α2//{1–11}γγ.

AlCrN and TiAlSiN coatings were deposited on the surface of 30CrMnSi steel and cemented carbide YT15 by multi-arc ion plating technique. A scanning electron microscopy was used to observe the surface morphologies of both coatings. The reciprocating sliding tests of AlCrN and TiAlSiN coating were performed to investigate the friction coefficients and the wear mechanisms of both coatings were analyzed as well. Dry machining tests on 30CrMnSi hardened steel were carried out with the AlCrN and TiAlSiN coated tools on a CA6140A lathe. The effects of cutting speed on cutting forces and cutting temperatures of AlCrN and TiAlSiN coated tools were obtained and analyzed. The microcosmic micrographs of wear areas of both coated tools were observed and investigated by scanning electron microscope and energy dispersive spectrum. The results show that the hardness and bonding strength of AlCrN coating are higher than that of TiAlSiN coating, while the friction coefficient of AlCrN coating is lower than that of TiAlSiN coating. Both the cutting force and cutting temperature of AlCrN coated tool are lower than TiAlSiN coated tool. The time required for the bluntness of the AlCrN coated tool is approximately 33.3% longer than that of the TiAlSiN coated tool, and the main wear mechanisms of both tools are mainly crater wear, diffusion wear and oxidation wear.

Physical vapour deposition technique was used to deposit TiAlCrN coatings on the YT15 tungsten carbide inserts. The dry turning tests of 20CrMo steel were carried out to evaluate performances of TiAlCrN coated and uncoated tools on the CA6140A lathe. The effect of the two kinds of tools on cutting forces, cutting temperature, surface roughness and tool wear had been investigated to assess the performance of TiAlCrN coated tools. The results showed that the cutting force and cutting temperature obtained by TiAlCrN coated tools were decreased and the TiACrN coated tools produced a better surface finish in comparison with the uncoated tools. The TiAlCrN coated tools yield working life about 45 min, which was two times of that for uncoated tools. The wear mechanisms of the TiAlCrN coated tools were mainly oxidation and boundary wear, accompanied with diffusion wear.

A high-efficiency inverted-type CH3NH3PbI3 (MAPbI3) solar cell was fabricated by using a ultrathin poly[3-(4-carboxybutyl)thiophene-2,5-diyl]-Na (P3CT-Na) film as the hole transport layer. The averaged power conversion efficiency (PCE) can be largely increased from 11.72 to 18.92% with a double-filtering process of the P3CT-Na solution mainly due to the increase in short-circuit current density (JSC) from 19.43 to 23.88 mA/cm2, which means that the molecular packing structure of P3CT-Na thin film can influence the formation of the MAPbI3 thin film and the contact quality at the MAPbI3/P3CT-Na interface. Zeta potentials, atomic-force microscopic images, absorbance spectra, photoluminescence spectra, X-ray diffraction patterns, and Raman scattering spectra are used to understand the improvement in the JSC. Besides, the light intensity-dependent and wavelength-dependent photovoltaic performance of the MAPbI3 solar cells shows that the P3CT-Na thin film is not only used as the hole transport layer but also plays an important role during the formation of a high-quality MAPbI3 thin film. It is noted that the PCE values of the best P3CT-Na based MAPbI3 solar cell are higher than 30% in the yellow-to-near infrared wavelength range under low light intensities. On the other hand, it is predicted that the double-filtering method can be readily used to increase the PCE of polymer based solar cells.

TiAlN coating was deposited on the surface of 20Cr steel samples by physical vapor deposition. TiAlN coated samples and 20Cr steel matrix samples were in three conditions of friction to do reciprocating friction and wear tests with a Si3N4 ceramic ball friction pair which was loaded 2, 5 and 8 N. The wear images and the distribution of elements were obtained by the scanning electron microscope and the energy spectrometer respectively. Then the three-dimensional profile meter was used to get the profile of the grinding marks and the step meter gained two-dimensional contour curve. Results of investigation showed that the friction coefficient of TiAlN water-based lubrication friction increased with the increase of the load, and TiAlN oil-based lubrication friction had the same rule. Under 5 and 8 N loads, the friction coefficients were higher than both of TiAlN and 20Cr steel matrix dry friction in the middle friction stage. As concluded through the experimental analysis, abrasive wear was the main wear mechanism of dry friction; the fatigue wear and oxidation wear were accompanied in some conditions. Water had a great influence on the micro morphology of the grinding mark. The wear of 20Cr steel matrix is the most serious.

TiN coated and uncoated tools were used to conduct the dry cutting temperatures for AISI 304 stainless steel. Effects of cutting variables on cutting temperatures were investigated using single factor experiment method. The optimal cutting parameters of cutting temperatures were obtained through orthogonal experiment method. The forming process and temperature distribution of chips were analyzed using finite element method (FEM). The results show that cutting temperature generally increases with the increase of cutting speed and feed rate. When depth of cut increases at the range of 0.8-1.5 mm, the cutting temperature increases firstly and decreases subsequently. And the cutting temperature of TiN coated tool is lower than that of uncoated tool. The optimal parameters of cutting temperature are obtained by orthogonal experiment, which is A1B1C3. The highest temperature appears on the second deformation zone by the simulation.

A numerical simulation and experimental measurements are performed to characterize the flowfield of oxygen/oil gas-jet facility. Chemical non-equilibrium Navier-Stokes equations have been solved to acquire the axisymmetric combustion-heated stream condition. The numerical results indicate that chemical reactions have an impact on flow oscillation, which alleviate the rate of decay of flow and make shock region move downstream. Flow diagnostics has been conducted to measure flow properties. Distributions of the pressure, temperature and Mach number along the centerline of the exit plane are experimentally obtained. The comparison has been presented between simulation and measurement. Static pressure distribution measurements show a good agreement with the numerical results. The computed temperatures are higher than measured ones, but the trends of oscillation and declension are nearly the same. Possible reasons of the difference are mainly because of uncertainly in chamber pressure and combustion efficiency.

The detection ability of laser fuze is easily disturbed by smoke, which causes false alarm. In order to study on the backscattering characteristics of pulsed laser fuze in smoke, the relevant model based on Mie scattering theory and Monte Carlo method was established, and the backscattering signal in smoke was simulated using 905 nm pulsed laser. To verify the accuracy of the model, the actual peak voltage was compared with the simulated normalized intensity and correlation analysis was conducted. Then, the backscattering characteristics of the pulsed laser fuze under different smoke concentrations, length of pipes and distances were analyzed. Finally, the influence of different smoke environment was obtained. The results can provide support for the anti-smoke interference of the pulsed laser fuze.

Using the pre-treatment of the working photoelectrode and the admixture light-scattering layer can ameliorate the performance of TiO2 dye-sensitized solar cells (DSSCs). TiCl4 treatments on TiO2 electrodes improve the adhesion and mechanical strength of the TiO2 layer. The HNO3 treatment significantly enhances the dispersion of TiO2 particles and increases the surface area and porosity of TiO2 films. The scattering layer formed by admixing both nanometer-sized and submicron-sized TiO2 particles greatly enhances the DSSC performance. The light absorption is considerably better in TiO2 films with a mixture of large and small particles. This mixture is capable of efficient light-scattering while simultaneously providing a larger surface area for effective dye adsorption. Each of these technologies for the TiO2 film fabrication has a significant influence on the overall photovoltaic parameters of DSSCs, resulting in improvements in energy conversion performance.

A high speed, high resolution spectrum measurement system based on fiber-spectrometer was built to diagnose the high temperature hypersonic combustion flow. The theoretical models of the spectral radiance and transmittance of the hypersonic combustion flow were established in this paper. The spectral radiance and transmittance of the hypersonic combustion flow were measured at the combustion wind tunnel of BISLMV. Preliminary experiments showed that the spectral radiance behaved not like typical gas radiation but have a continuous spectrum, and the spectral transmittance of the combustion gas flow was about 0.9 in the spectral range 500-900nm without strong spectral selection. The results obtained in this paper will benefit the surface temperature measurement of the thermal protection materials of space vehicle tested at BISLMV.

Temperature is a critical parameter to diagnose the high temperature hypersonic combustion flow. A fiber-spectrometer based measurement system and the correlated theoretical models to measure the radiation temperature of the “optical thick” hypersonic combustion flow were established in this paper. The spectral responsivity of the fiber-spectrometer based measurement system was measured at NIM in lab condition, and the spectral radiance and emissivity of the hypersonic combustion flow were measured in-situ at the combustion wind tunnel of BISLMV. Preliminary experimental results showed the spectral emissivity of the combustion flow was about 0.1 in the spectral range 500-800nm without strong spectral selection, which resulted in the radiation temperature about 2200 K, with relative standard uncertainty about 10%.

The effects of mole ratio of formaldehyde and melamine (F/M), solution pH, reaction temperature and time on the foaming melamine-formaldehyde resin (MF resin) with caprolactam as modifier were investigated by orthogonal experiment design where the solid content and the viscosity of the resin, the density and the size uniformity of the foam resin were used as performance evaluation parameters. The results had shown that the optimal conditions for preparing the foaming MF resin were F/M= 3.25, pH=8.0, T=90°C, t=45min. The MF resin prepared under the optimal conditions could be foamed well and its storage time was prolonged to 16 days. The structure and thermal properties of MF resin under the optimal conditions were investigated.

In order to researching the microstructure of bioceramic coating on the surface medical titanium alloy (Ti–6Al–4V), the gradient bioceramic coatings are fabricated by wide-band laser cladding. The influence of multiple rare earths oxide La2O3 and CeO2 on microstructure of bioceramic coating were studied. The experimental results demonstrated that mixed La2O3 and CeO2 have an effect on forming-ability of HA\β-TCP in bioceramic coating and also refined the grain of bioceramic coatings. The largest amount of HA\β-TCP is presented among all the groups when the contents of La2O3 and CeO2 are 0.6wt.%, 0.4 wt.%, respectively.

To improve bioactivity of gradient bioceramic coating, the coating with two kinds of rare earth oxide was produced by wide band laser cladding technique. As the experimental results, whichadded0.6wt.% La2O3 fixedly, and increased the addition amount of the CeO2, when the addition of CeO2fulfill 0.4wt.%, the amount of HA-β-TCP is the largest in this experiment. Soaking the specimens in SBF for 14 days, the coating blended 0.6wt% La2O3 and 0.4wt% CeO2, then a great quantity of Ca-P white particles can be found on coating, which confirmation this bioceramic coating is of best bioactivity.

To obtain the coating with excellent properties, FeWCrMnCoCuTix(x=0.2, 0.4, 0.6) high entropy alloys coating on 45 steel were prepared by laser cladding. By means of OM, XRD and microhardness tester, the effect of Ti content on microstructure and properties of coating is investigated. The experimental result shows that the phase composition of HEAs coating is simple body-centered cubic and face-centered cubic. The microstructure of these alloys is mainly dendrite crystal with grains were fine and uniform. When Ti content increases tox=0.4, the hardness of the coating reaches a maximum (639HV0.2). Key words: HEAs; FeWCrMnCoCuTix; coating; laser cladding; microstructure and properties

The mesoporous anatase TiO2 material was prepared by ionic liquid-assisted hydrothermal method using tetrabutyl titanate as titanium source and ionic liquid 1-butyl-3-methylimida-zolium tetrafluoroborate ((C4MIM)BF4) as template. The pH values of the starting suspensions were adjusted from 1 to 11 using HCl or NH3·H2O solution. The influence of pH on the ionic liquid-water system for the preparation of titanium dioxide was investigated. The obtained TiO2 samples were characterized with X-ray diffraction (XRD) and N2 adsorption-desorption measure- ments, respectively. The results showed that the addition of ionic liquid inhibited the formation of the brookite TiO2, and increasing pH values enhanced the crystallization. When the pH was changed at a wide range (pH=1~9), the pore size distributions of the samples were relatively narrow, and the average pore diameter was reduced from 6.6 nm to 5.0 nm by increasing pH value. At the same time, the average size of the TiO2 nanoparticles in the samples was controlled at about 9 nm by using ionic liquid-assisted hydrothermal method. This is consistent with the results of the transmission electron microscopy (TEM) analyses.

Lead-free 0.996(Ba0.85Ca0.15)(Zr0.1Ti0.9)O3-0.004BiYO3 [BCZT-BY] ceramics were prepared by the conventional solid-state sintering method. By means of XRD, SEM, and quasi-static d33 meter etc., the effect of sintering temperature on the microstructure, piezoelectric and dielectric properties of BCZT-BY ceramics were investigated. All the ceramics possess a pure perovskite structure, indicating that Bi3+ and Y3+ are incorporated into Ba0.85Ca0.15Ti0.9Zr0.1O3 lattices to form a solid solution. The results show that the ceramics sintered at 1420°C exhibit the optimum electrical properties: d33 = 130 pC/N, kp = 18.2 %, εr = 4225, and tan δ = 1.95%, respectively.

Ni-B amorphous alloy particle is a newly promising candidate of catalyst for methanol electrooxidation in Direct Methanol Fuel Cell (DMFC). For enhancing catalytic activity and increasing surface area, mesoporous Ni-B amorphous alloy nanoparticles was manufactured by chemical reduction of NiCl2 and KBH4 via surfactant hexadecyltrimethyl ammonium bromide (CTAB) as an soft template. The effects of the CTAB content and the feeding order on the phase evolution, microstructure, and surface area of the resulting products were investigated. Phase and structure of the samples were investigated using XRD, SEM and BET. Amorphous Ni-B nanoparticles with mesoporous structure were obtained in this study. The CTAB content great impacted the mesoporous structure of the resulting products, although the obviously effect on the phase was not found. The surface area, pore volume and pore diameter of samples improved with the increase of CTAB content. Compared to nanoparticles obtained by CTAB solution added to NiCl2 solution, nanoparticles obtained by NiCl2 solution added to CTAB solution exhibited better mesoporous structure.

To obtain high-entropy alloys (HEAS) coating with excellent properties on Q235 steel, a kind of HEAS powders was designed. The HEAS coating was prepared uniformly on Q235 steel by laser cladding. By means of OM, XRD and microhardness tester, the microstructure and properties of the high-entropy alloy layer were investigated. The experimental results indicate that the phases in the high-entropy alloy coating is mainly MoFeCrTiW with simple BCC, whose lattice parameter is a-3.1256Å. The microstructure in the coating is mainly cellular crystal, on which dispersion precipitates exist. And in the near bottom of the coating, there is few precipitates, in the middle part of coating, the precipitates are larger than that of bottom coating, while in near top of coating, dispersion precipitates become largest. The maximum microhardness value of coating reaches 800HV0.98.

To improve voltage-gradient and to reduce the sintering temperature of ZnO varistors, high voltage-gradient ZnO varistors were synthesized with a conventional solid state reaction route. By means of SEM and DC parameter instrument for varistor, the influence of different technological parameters on microstructure, voltage-gradient and leakage current of ZnO varistors was investigated. The experimental results show that by using the process that presintering the additives at 850°C, the density is improved, the voltage-gradient is increased, and the leakage current is decreased. The optimum voltage-gradient and leakage current are 371V/mm and 3μA, respectively.

To obtain lead-free 0.5Ba (Zr0.2Ti0.8)O3-0.5(Ba0.7Ca0.3)TiO3 ceramics with excellent microstructure and electrical properties, BZT-BCT ceramics doping Mn4+ and Nb5+ was synthesized follow a conventional solid state reaction route. By means of SEM, XRD, quasi-static d33 meter, the influence of sintering temperature on microstructure, piezoelectric and dielectric properties of BZT-BCT-Mn-Nb ceramics was discussed. The results show that grain size and the dielectric loss of BZT-BCT-Mn-Nb ceramics increase as raising the sintering temperature. When BZT-BCT-Mn-Nb ceramics is sintered at 1380°C, the optimum piezoelectric coefficient and dielectric constant are 264pC/N and 4142, respectively.

The study aimed at phosphorus and nitrogen removal by honeycomb cinder modified with Zinc chloride (ZnCl2). By bench-scale batch experiments, honeycomb cinders with different modification time and ZnCl2 dosage were modified and its adsorption capacities were evaluated by methylence blue as the adsorbate. Under the optimal modification conditions, large amount modified honeycomb cinders were prepared to remove the phosphorus and nitrogen from domestic sewage, which different operating conditions of honeycomb cinders dosage, and contact time were considered. The results show that removal efficiencies of total phosphate (TP), orthophosphate (PO43-P), total nitrogen (TN) and ammonia nitrogen (NH4+-N) could reach 89.9%, 96.7%, 18.9% and 23.3% under the optimal conditions, respectively. Modified honeycomb cinders might be an effective and low cost adsorbent for phosphorus removal.

To improve bonding strength between Ti alloy and bioceramic coating and to eliminate thermal stress during laser cladding, gradient bioceramic coating materials is designed. The bioceramic coating is fabricated by wide band laser cladding technique. And the effect of adding single and multiple rare earth oxide on microstructure is investigated. The samples are soaked with SBF for 14 days, the experimental results indicate that when the content of single rare earth oxide is 0.6wt.%Y2O3, a large number of bioactivity phase and chrysanthemum shape microstructure can be observed. When the content of single rare earth oxide is 0.2wt.%Sm2O3, a lot of bioactivity phase and coral reef shape microstructure can be observed. When the content of multiple rare earth oxide is 0.3wt.%Sm2O3 and 0.4wt.%Y2O3, a large amount of bioactivity phase and more homogeneous and dense spherical particles can be observed on coating, which demonstrates the microstructure is of better bioactivity.

To improve bonding strength between titanium alloy and coating and to eliminate thermal stress during laser cladding, a gradient coating materials is designed. And the gradient coating with different contents of multiple rare earth deoxide was produced by wide band laser cladding technique. The experimental results indicate that when addition of Sm2O3 is fixed to 0.3wt.%, as addition of Y2O3 increases, the microstructure of bioceramic is different. When addition of Y2O3 reaches 0.4wt.%, the amount of Ca-P based bioactive phases such as HA, α-TCP as well as β-TCP becomes biggest. After soaking the coating with 0.3wt.% Sm2O3 and 0.4wt.% Y2O3 in SBF for 14 days, a large amount of Ca-P white spherical particles can be observed on coating, which demonstrates the bioceramic coating is of best bioactivity.

To improve the quality of bioceramic gradient coatings, wide band laser cladding technique was adopted to produce a kind of gradient composite bioceramic coating, which combines the good biocompatibility of HA and β-TCP with good toughness and strength of TC4 alloy. The rare earths oxide La2O3 was added to improve the properties of the bioceramic coating. The results indicate that when the adding of La2O3 is 0.6wt%, the ceramics coating is of the largest amount of HA and β-TCP catalyzed, and the number of cells proliferated and the ALP secreted on coatings is the biggest, which indicates that the biocompatibility and bioactivity of gradient bioceramic coating is the best. The biocompatibility and bioactivity are closely related to the amount of HA and β-TCP catalyzed by La2O3.

Zn(II)meso-tetra(α,β,α,β-o-pivalamidophenyl)-porphyrin was synthesized as a sensing material. It indicated an excellent film performance and significant optical response ability, which can be used for gas detection, such as: NO2, SO2and NH3.This material was characterized by IR, NMR, and AES, and its Langmuir-Blodgett films properties were also studied by means of UV-Vis-spectroscopy. The results showed that the zinc porphyrin’s UV spectrum and LB films properties occurred a great change compared with protoporphyrin, and it also had a good film forming capability and stability.

To improve the service life of roller, a kind of alloying powder materials with CeO2 was designed. And the surface of roller was alloyed by a 5kW CO2 laser. The effect of CeO2 on microstructure and properties was studied by means of OM, Micro-hardness Testing Machine, Friction and Wear Tester. The experimental results indicate that addition of CeO2 into coating materials can refine and purify microstructure. Microstructure in alloying layer is coarse without CeO2, when CeO2 is up to 2.0wt.%, microstructure in alloying layer becomes finest. And microhardness and wear resistance become largest.

o improve the electrical properties of PSZT piezoelectric ceramics, a ceramic powder Pb0.94Sr0.06(Zr0.52Ti0.48)O3 (PSZT) with Nb2O5 was designed. The power was prepared by solid state sintering. The surface structure of sample was characterized using SEM, and the crystal structure of the sample was examined by XRD. The capacitance and dielectric loss of sample was measured by Tonghui Electronics TH2618 capacitor tester. The result of microstructure and electrical properties show that Nb2O5 inhibit crystal growth when the contents of Nb2O5 is less than 0.5.wt%, but excessive Nb2O5 cause pyrochlore phase producing while the contents of Nb2O5 more than 0.5wt.% . The excellent piezoelectric properties are achieved in the ceramics with 0.5wt.% Nb2O5:εr=1504,tanδ=0.0065,d33=336pC/N, kp=0.562.

Nowadays, the piezoelectric materials are widely used in many areas. The piezoelectric materials will undergo an electrical degradation process during working causes the piezoelectricity and resistance of the piezoelectric materials degrade. The existence of the electrical degradation phenomenon severely limits the applications of the piezoelectric products. During the electrical degradation process, electrical breakdown often occurs and this electrical breakdown has been proposed [1, 2] induces the resistance decrease and local phase changing. In this paper, the electrical breakdown induced current transients are detailed investigated. Three types of current transients are presented and the time durations of current transients are suggested not constant and corresponding to the time duration of the local burn-out process, which is caused by the heat released from the electrical breakdown process.

The computer aid simulation of optical properties of thin films has been used to optimize SiO2/TiO2/SiO2 multilayer films to obtain high transparent films in this paper. The maximum transmittance at the visible light wavelength range is proper criteria for optical films optimizing design. The effect of design parameters (film thickness and refractive index) on optical properties of SiO2/TiO2/SiO2 multilayer films were also discussed in detail. According to the result of optimization, high quality SiO2/TiO2/SiO2 multilayer film with a maximum of > 99% at visible light wavelength range can be achieved on the glass.

In this paper, optical, the chemistry stability, and glass transformation, softening temperature were studied on Bi2O3-SiO2-ZnO-B2O3 system glass doped with 2wt.%、4wt.%、6wt.% and 8wt.%TiO2. The results showed that glass surface has no stripes and defects with transmittance between 20%-50%. Moreover, with the increasing of Ti content, the results of the experiments indicated that the metal oxides TiO2 could enhance the glass chemical stability most clearly, and regulate the glass transformation temperature.

To improve the service performance of roller. The surface of roller was alloyed by a 5kW CO2 laser. The effect of CeO2 on microstructure and hardness was studied by means of OM, Micro-hardness Testing Machine and Rockwell hardness tester. The results indicate that addition of CeO2 into coating materials can enhance the fluidity of molten liquid, refine and purify microstructure and increase microhardness and surface hardness of alloying coating.

The effects of curing electric field frequency on the electro-optic property of Polymer-Stabilized Cholesteric Texture(PSCT) is investigated.PSCT samples were prepared by means of polymerization induced phase separation(PIPS).By changing the curing electric field frequency,we can control the network morphology of PSCT and improve the electro-optic property.It was demonstrated that the diffusion of monomer and network morphology were related with curing electric field frequency.In addition,lower frequency promotes the diffusion of monomer and generally results in a open network with large void inside which often shows fast response,high closed transmittance,low threshold and low saturated voltage.On the adverse,higher frequency inhibits the diffusion and generally results in a closed network with smaller void inside which often shows slower response,lower transmittance,higher threshold and higher saturated voltage.

To obtain ZnO varistors with high voltage gradient, ZnO varistors were fabricated by traditional ceramic sintering technique, the effect of different sintering temperature (1135～1155 °C) on electrical properties of ZnO varistors were investigated. The experimental results show that with increasement of sintering temperature, the grain size of ZnO varistor ceramic becomes bigger, the voltage gradient of varistor decreases and the density is improved. When the sintering temperature is at 1135 °C, the voltage gradient of varistor is up to 329V/mm, the leakage current is 8μA and the density is 96.4%. When the sintering temperature is at 1140 °C, the voltage gradient of varistor is 301V/mm, the leakage current is 4μA and the density is 96.6%. Compared the results at 1135 °C with 1140 °C , it is found that the comprehensive electrical properties of ZnO varistors reach maximum at 1140 °C.

The molecularly imprinted technology and the self-assembly technique were used together on the calixarene surface acoustic wave (SAW) chemical sensors to detect organophosphorus compounds. 25-(thioalkyl-alkoxy)-p-tertbutylcalix[4] arene with self-assembled monolayer character was the sensitive coating of the sensors. The sensors had a special response to organophosphorus compounds and the response frequency shift of this sensor to organophosphorus compounds in 0.1 mg/m3 was 350 Hz. The response frequency increased linearly with the increase of the concentration of DMMP in the range from 0.1 to 0.6 mg/m3. The possible explanation of the interaction between the coatings and organophosphorus compounds was discussed.

To improve the room resistivity, 96MgAl2O4-2SiO2-2TiO2honeycomb ceramic doped with different Y2O3contents was fabricated by technique of raditional solid phase sintering. The microstructure and room resistivity of the samples were nvestigated by SEM and portable pH/Cond 3400i resistivity tester. The results show that as the amount of the Y2O3increases, room resistivity of the samples decreases gradually. When Y2O3content is up to 0.06mol%, the resistivity becomes minimum with 5.5×101Ω•m. When Y2O3content is up to 0.10mol%, the resistivity conversely increases.

To eliminate thermal stress during laser cladding and to raise the bonding strength between substrate and coating, composition gradient coatings are designed and fabricated by using wide-band laser cladding technique on a Ti alloy. The rare earth Nd2O3 was added to improve the properties of the bioceramic coating. The experimental results indicate that when the adding of Nd2O3 reaches 0.6wt%, the characteristic peaks of HA and β-TCP are the highest, which demonstrates the amount of HA and β-TCP is the largest. However, when the content of Nd2O3 is up to 0.8wt%, the peaks of HA and β-TCP conversely goes down. The biocompatibility and bioactivity are related to the amount of HA and β-TCP catalyzed by Nd2O3. When the content of Nd2O3 is 0.6wt%, the number of cells proliferated and the ALP secreted on coatings is the most, which indicate the biocompatibility and bioactivity of gradient bioceramic coating is the best.

To obtain ZnO arrester with high voltage gradient and small size, through the optimizing foundamental formula of arrester and changing sintering temperature and holding time, the electrical properties and microstructure of varistors were studied. The density of varistors was determined by using the mass - volume method , voltage gradient and leakage current of ZnO arrester were measured with Ⅱ Surge Arrester Tester DC parameters, microstructure of varistor ceramics were studied by means XRD and SEM. The experimental results show that with increasement of the sintering temperature, the density of varistors increases, and the voltage gradient continues to decrease and leakage current almost keeps unchangable. As the holding time increases, while as the voltage gradient continues to decrease, and leakage current almost unchanges.

To obtain ZnO varistors with high voltage gradient, ZnO varistors were fabricated by traditional ceramic sintering technique, which were sintered from 1135 to 1155 °C, the microstructure and properties of varistors were characterized by SEM, X-rays diffraction and DC parameter instrument for varistors. The experimental results show that the spinel phase Zn7Sb2O12 generated during sintering process, very thin amorphous Bi rich films are formed between the ZnO/ZnO grain boundaries, with increasement of sintering temperature, the grain size of ZnO varistor ceramic becomes bigger, the voltage gradient of varistor decreases and the density is improved. The optimized parameters are that when the sintering temperature is at 1140 °C, the voltage gradient of varistor is 301V/mm, the leakage current is 4μA and the density is 96.6%, the comprehensive electrical properties of ZnO varistors reach maximum.