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Microstructure and properties of laser cladded NiTi and NiTiCu coatings were investigated to reveal the effect of Cu addition in this system. The XRD and SEM results indicated that Cu addition formed a ternary phase TiNi0.8Cu0.2, distributed in the grain boundary region of the matrix. The microhardness of NiTiCu coating was much higher than that of NiTi coating, reaching 600–700 HV. The wear resistance was improved with the friction coefficient decreased by 25.8% and the wear loss decreased by almost 50%. This was due to the grain boundary strengthening and wetting effect caused by the intergranular ternary phase and the change of the phase transformation behavior.

The windows for the aerospace ship application is consist of fused silica and optical-films which can resist the ray-irradiation among the cosmos. For the optical-films produced by RF magnetron sputtering, the ray-irradiation anti-resist character is related with the sputtering temperature and the annealing temperature. As one of the high refractive index materials for the optical-design of the multi-layer optical film, CeOx film were exposed to Co60 irradiation of 107 、108 、and109rad(Si) respectively. The spectrum- transmission line showed the optical character before and after the irradiation. Due to the decreasing of the defect among the film with the raising of the temperature ,the higher the sputtering and annealing temperature, the well anti-irradiation character. The transform of the Ce3+ and Ce4+ is beneficial for the optical character while the E’ center can be moved from the visible-band to the ultraviolet band. But with the raising of the irradiation does, the micro-structure is key for the anti-irradiation character of the CeOx film.

The fused silica glass is widely used in the photoelectricity and semiconductor industry, and needed to be cut or made small holes and micro grooves on it. Recent reports indicate that laser processing is one of important means for fused silica glass. First of all, the laser processing characteristics of fused silica glass was discussed in this paper. Besides, 532nm wavelength and CO2 laser were used to process or cut fused silica glass, and different results were found. 532nm laser is more suitable for processing holes and micro grooves on thin fused silica glass. Then CO2 laser can be used to cut thick fused silica plate or marked on the glass surface. In addition, the two laser machined surface was observed with 3D microscope, and it displays huge surface differences. The first one is rough, and another is smooth.

In recent years, the concrete-filled narrow rectangular steel tube (CFNRST) has drawn much attention for practical engineering applications. Compared with the commonly used concrete-filled rectangular steel tube (CFRST), the cross-sectional aspect ratio (the ratio between widths of wider and narrower sides of the steel tube) of CFNRST is larger and exceeds 2.0, which is considered as the upper limit of aspect ratios for ordinary CFRSTs reported in the literature. In this paper, experimental results are presented involving 24 specimens of CFNRST stub columns subjected to axial compression. The axial resistant behavior of CFNRST columns is investigated concerning the effects of key parameters including: (a) cross-sectional aspect ratio, (b) confining factor, and (c) width-to-thickness ratio of wider side of steel tube. By analyzing the observed and measured test results, the failure modes, ductility performance, strength enhancement effect and residual resistance of the specimens are discussed in detail. Moreover, 173 test results of CFRST stub columns under axial compression reported in the literature are collected and compared with the test results of this study; hence, the effect of extremely large cross-sectional aspect ratio on the behavior of CFRST columns is presented. Finally, typical equations specified in design codes are examined to reveal their validity in predicting the ultimate axial resistance of both CFNRSTs and ordinary CFRSTs. This study can provide valuable information for practical designs of CFNRST stub columns under axial compression.

TiO2-SiO2 is a kind of binary component glass material with excellent properties such as high heat impact resistance, welding ability, and the size of the material is insensitive to temperature change. Based on the principle of Chemical Vapor Deposition (CVD), we used silicon tetrachloride and titanium tetrachloride as the raw materials for the preparation of this glass. In this research, we studied the morphology, structure, and particle size distribution of TiO2-SiO2 binary glass particles. The experimental results show that the deposition particles are spherical amorphous nanoparticles with a size of about 100nm, and there is no SiO2 or TiO2 crystalline phase in the particles. This particle structure overcomes the characteristic that TiO2 is easily crystallized in other preparation methods, making preparation for TiO2-SiO2 binary glass possible.

A new synthesis strategy to prepare hierarchical macroporous–mesoporous materials employing poly(ethylene oxide)-poly(phenylene oxide)-poly(ethylene oxide) (PEO-PPO-PEO) as a single template and an acid adjusting agent was reported. There is a hierarchical structure including macropores with a size of 50–100 nm and mesopores in the macroporous walls with a size of 3–5 nm. The macroporous walls are composed of rare earth orthoferrite nanoparticles with a size of 5–10 nm. These hierarchically porous materials show high catalytic activities for the CO + NO reaction, and NO can be fully converted to N2 at temperatures as low as 350 °C, indicating their potential in the catalytic conversion of automotive exhaust gas and other catalysis-related fields. This synthesis strategy is a facile method for the preparation of hierarchical porous materials and may give us a guideline for the synthesis of functional materials with further catalytic applications.

The occurrence of the damage among the silica glass being laser-irradiation is closed related with the hydrogen. The laser of 248nm lead to the structure collapsing to made the silica glass crystallized. With the crystallized and non- crystallized parts, the 1H MAS NMR result shows that the concentration of the hydrogen are different of the damaged and non-damaged silica glass. Which is the evidence for the damage-delaying by the hydrogen.

The laser damage character of fused silica is studied experimentally. Firstly the distribution of the defects is presented. Furthermore, the relevancy of the laser damage character and the defects is discussed. Finally, the fluorescence of damage-occurring is explained. From the result, the way to ameliorate the laser damage character by controlling the defects is given.

Through a pull-out test was designed. The load-slip curves between recycled concrete with different recycled coarse aggregate replacement percentage and rebar were recorded. This article studied the impact of different recycled aggregate replacement rate and the anchorage length for the bond strength between the recycled aggregate concrete and reinforced, and provided a beneficial reference for engineering design of recycled concrete structure under similar conditions. Determined the recycled concrete and reinforced the bond-slip constitutive relation. Come to the bonding properties of reinforced recycled concrete with recycled aggregate rate increase gradually decreased in the anchorage length sufficient to meet the design requirements, performance depended on the pull-out strength of reinforced recycled concrete and reinforced the bond.

Tensile behaviors of an AZ80 alloy were investigated by elongation-to-failure tensile tests at 300, 350, 400 and 450 °C, and strain rates of 10 −2 and 10 −3 s −1 . Strain-rate-change tests from 5×10 −5 s −1 to 2×10 −2 s −1 were applied to study deformation mechanisms. The experimental data show that the material exhibits enhanced tensile ductilities of over 100% at 400 and 450 °C with stress exponent of 4.29 and activation energy of 149.60 kJ/mol, and initial fine grains preserve in evenly deformed gauge based on microstructure studies. The enhanced tensile ductilities are rate controlled by a competitive mechanism of grain boundary sliding and dislocation climb creep, based on which a model can successfully simulate the deformation behavior.

In2O3/multi-walled carbon nanotube (MWCNT) nanocomposites containing different MWCNT contents were synthesized via direct growth of In2O3 nanoparticles on the functionalized MWCNTs. The nanocomposites were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray photoelectron spectroscopy (XPS). The results exhibited that In2O3 nanoparticles with a diameter of approximate 10 nm were densely decorated on the surface of the MWCNTs. The gas sensitive performance of the nanocomposites to ethanol was also investigated. It was found that In2O3/MWCNTs sensor showed much higher response than that of the pure In2O3 sensor. Moreover, the sensing mechanism was discussed.

The fused silica have being used as the lens on the spacecraft ,In order to enhanced the optical character, the film works .We studied the changing of the ZnO film on the fused silica under the radiation of the 60Co irradiation which is close to the actual-condition. The anti- irradiation character under the 60Co γ-ray of the is ZnO film not good while the heat-treatment of the film leading to the optimizing of the physical-character under the radiation of the 60Co γ-ray. The cracking of the film is obvious being irradiation.

Microstructural features and tensile behaviors of an AZ31 alloy with Nd and La additions were investigated with elongation-to-failure tensile tests at constant temperatures of 300 °C, 350 °C, 400 °C, and 450 °C, and constant strain rates of 10-2s-1and 10-3s-1. Experimental data show that the material exhibits tensile ductilities of over 100% at 450 °C, featured by long steady state deformation. Microstructure studies show that annealed coarse grains were remained in the gauge region after the tensile tests, and the dominate deformation mechanism was dislocation creep, other than dynamic recrystallization or grain boundary sliding. Cavity evolution near fracture end caused premature failure of the material, although fine grains developed through dynamic recrystallization.

Three different CeO2 sphere nanomaterials (hollow sphere, flowerlike sphere, spherical cluster) were controllably synthesized by carbon sphere template method, hydrothermal and solvothermal method respectively. Then 2.5 wt% Au was doped on the supports by the deposition precipitation method and Au/CeO2 catalysts with three different morphologies were obtained. Composition, morphology and structure of these catalysts were characterized by the techniques of XRD, Raman, TPR, SEM and TEM, and the activity for CO oxidation of the catalysts was investigated. The catalytic test results indicated that the addition of Au could remarkably improve catalytic performance on CO oxidation. The activities of the three catalysts differ largely, the flowerlike Au/CeO2 catalyst had the highest activity for CO oxidation and its T100% was 29°C. The mechanism for the different activity of the catalysts was investigated. H2-TPR result indicated flowerlike had a more intensive peak at 125°C than others and it implied more reducible Au species in this case, that plays a vital role in the CO oxidation.

Crystal structures and optical properties of the δ−O2 phase and the −O8 phase have been investigated by using the ab initio pseudopotential plane-wave method. It is found that the phase transition is of the first order with a discontinuous volumetric change from the antiferromagnetic δ−O2 phase to the nonmagnetic −O8 phase, consistent with the experimental findings. The energy band calculations show that the direct band gap changes into an indirect band gap after the phase transition. The apparent change in the optical properties can be used for identifying the phase transition from δ−O2 to −O8.

Iron oxide nanoparticles have been synthesized by laser-induced vapor-phase reaction. Mean diameter of the particles varied from approximate 4 nm to 40 nm and the crystalline phase was transited from γ-Fe2O3 to α-Fe2O3 with increasing operation temperature. The nanometer-sized α-Fe2O3 powders were used to fabricate a thick film based gas-sensitive sensor. The effects of the doped noble metals or carbonate and the calcination temperature on sensitivity of the sensor were studied. The results show that the α-Fe2O3 was doped with 3% noble metal or SrCO3 presents the best sensitivity to CO.

We perform an ab initio study on the electronic structure and charge density of the e-oxygen under high pressure, which is obtained by powder x-ray diffraction experiment recently. Our results show that the hybridization among the σg*, πu and πg* bands in the e-oxygen are not significant even at megabar pressure. Pressure-induced metallization occurs due to the band overlapping near the Fermi level at about 50 GPa. A new network along the b-axis is formed and the O8 characteristic in the e phase disappears above 50 GPa even though the symmetry remains unchanged.

This paper demonstrates a compact combline filter based on multilayer Low Temperature Co-fired Ceramic (LTCC) technology. According to the combline theory and full-wave electro-magnetic (EM) comparing simulation, a filter operates at 2.3GHz–2.75GHz with dimension of chip-size 1812(4.5mm × 3.2mm × 1.5mm) is designed and fabricated. It generates a wide stop-band with three transmission zeros at the high-side skirt at 3.3GHz, 5.2GHz, 5.7GHz respectively to reject interferential frequencies. The passband insertion loss is less than 2dB. The measured results evidence the feasibility of the proposed design.

Highly ordered mesoporous ZnTiO(3) with crystalline walls was directly prepared by a sol-gel process combined with evaporation induced self-assembly in ethanol, using amphiphilic triblock copolymers as structure directing agents. The whole process is self-adjusting to organize the network-forming metal oxide species without additional acid or base. The mesoporous material is pure cubic-phase ZnTiO(3) and has large surface area (up to 134 m(2)/g), large pore volume (0.17 cm(3)/g), and narrow pore size distribution (3-4.5 nm). The optic behavior was systematically studied, which is very helpful to understand the mesoporous ZnTiO(3) material either in fundamental study or for potential applications in optics and catalysis. This work provides a "self-adjusting" approach to fabricate the mesoporous functional materials with diverse compositions: the diverse hydrolysis-condensation kinetics of various metal oxides is homogenized to yield stable multicomponent precursors. The development of such a simple, versatile, and reproducible method is important for applications in practice.

An effective synthetic strategy is demonstrated for preparing highly ordered crystallized mesoporous TiO(2) by introducing rare earth in the synthesis process; the obtained product exhibits near-infrared photocatalytic activity.

The low-alloyed transformation induced plasticity(TRIP) steels demonstrate an improved combination of strength and ductility,and have became a promising candidate for the application of automotive bodies to reduce the weight without the loss of crash-worthiness.The typical microstructure of TRIP steels consists of the ferrite matrix and a dispersion of bainite.niartensite and the retained austenite.The existence of an amount of metastable retained austenite is responsible for the improved mechanical properties,resulted from the enhanced strain hardening capabilities of TRIP steels due to the strain-induced martensitic transformation during straining.The carbon content is considered as an important factor that influences the amount and stability of the retained austenite. In the present work,two cold-rolled C Mn Al-Si TRIP steels with different carbon contents, (0.1%and 0.2%,mass fraction) were fabricated by intercritical annealing and isothermal transformation. The microstructures and the mechanical behaviors of the used steels were investigated by OM,XRD and uniaxial tensile tests at room temperature.The results indicated that with the same isothermal transformation time at 400℃.the steels with high carbon content obtained lower fraction of bainite and larger fraction of martensite,and demonstrated higher strength and larger elongation than those of steels with low carbon content.The excellent ductility of steels with high carbon content was mainly attributed to its strong TRIP effect during deformation,resulted from the larger fraction of retained austenite as well as the higher carbon content of retained asutenite in the multiphase microstructure.The value of the product of tensile strength and total elongation,representing the combination of strength and ductility of steels,was increased linearly with the increase of the value of the product of volume fraction and carbon content of retained austenite,which could be used to characterize the TRIP effect.Variation of the formation rate of strain-induced martensite was similar to that of the incremental strain hardening exponent with strain during deformation,further proved the important role of TRIP effect in influencing the strain hardening capabilities of TRIP steels.

A kind of chalcogenide glass midinfrared dual-core photonic crystal fiber has been proposed in this paper. The coupling characteristic of this fiber has been studied by multipole method using the basic theory of coupling. It is found that the birefringence of dual-core PCF with pitch 5.4 μm, air-hole radius 1.35 μm and air-filling fraction 0.5 is 0.551×10-2 at normalized frequency λ/Λ = 2.04 μm. At normalized frequency λ/Λ = 0.93 μm, coupling lengths are 145.32 μm and 154.68 μm for x-polarized mode and y-polarized mode, respectively. The band extended to midinfrared. This dual-core photonic crystal fiber with coupling length and high polarization is useful for manufacturing midinfrared band optical fiber coupler.

This paper proposes three kinds of tapered holey fibres with a multi-layer of holes whose pitch of air holes at the end of untapered and tapered are 5.8 μm and 1.8 μm. The central wavelength which locates in the anomalous dispersion region is 1.55 μm. An adaptive split-step Fourier method is numerically used to study the pulse propagation in tapered holey fibres. For the considered convex tapered holey fibre, at a wavelength of 1.55 μm, a compression factor of 136.7 can be achieved by initial width of 800 fs propagation through a length of 0.8 m. It demonstrates that in anomalous dispersion region, pulse can be compressed with the increase of nonlinearity coefficient and the decrease of dispersion coefficient.

A kind of high birefringence SF6 soft glass photonic crystal fiber (HBSF6-PCF) is proposed. The properties of birefringence, dispersion, nonlinear coefficient and the transmission characteristics are studied by the multipole method and the adaptive split-step Fourier method. The numerical results show that the birefringence and the nonlinear coefficient reach the orders of 10-2 and 10-1, respectively. In addition, the HBSF6-PCFs can generate very smooth supercontinuum spectra when illuminated with femtosecond pulsed light of 1064 nm. It is found that up to 800 nm spectral width (evaluated at −5dB from the peak) is achieved. Therefore, the advantage of the HBSF6-PCFs is such that a high birefringence, a high nonlinearity and a smooth supercontinuum are perfectly combined in them.

A kind of linerly tapered microstructure fiber has been proposed in this paper. The central wavelength, which is located in the anomalous dispersion region, is 1550 nm. We use an adaptive split-step Fourier method to numerically study the propagation of 1 ps laser pulse in this microstructure optical fiber. For the tapered fiber under consideration, a compression factor of 56.9 and a quality factor of 27 can be achieved in a fiber 1 m long. With the pulse shape evolution in the fiber, we find that in anomalous dispersion region, the pulse can be highly efficiently compressed by the increasing of nonlinearity coefficient and the decreasing of dispersion coefficient. Compared with the normal photonic crystal fibers, the thicker end of the tapered fiber is apt to be coupled to the laser pulse which has a larger effective mode area.

Photonic crystal fibers（PCFs）with rectangle core and elliptical core have been designed.Their fundamental characteristics are studied by electromagnetic scattering theory of multipole method.It is found that the fiber birefringence,dispersion and nonlinear characteristics can be flexibly adjusted by changing the radius of the air holes in the core.The PCFs have the following characteristics: With the increase of radius r 1 of air holes in the core,the birefringence increases and the wavelength corresponding to the maximum birefringence shifts towards the longer wavelength region,the number of zero-dispersion-wavelengths increases from one to three and nonlinear coefficient of the short-wave band decreases while it increases in the longer wavelength region.The three zero-dispersion-wavelengths of elliptical core PCFs with r 1 = 0.4 μm are located in visible,near-infrared and mid-infrared band,respectively.For similar structural parameters,elliptical core PCFs can achieve high birefringence and high nonlinearity more readily than rectangular core PCFs.

A kind of double-cladding photonic crystal fiber (DC-PCF) with high birefringence and two zero-dispersion wavelengths is proposed. It is found that the birefringence of DC-PCF with inner cladding air holes pitch 1.0 μm and diameter 0.8 μm is 1.001 × 10−2 in the optical communication band at wavelength 1.55 μm by the multipole method. It is demonstrated that two zero dispersion wavelengths can be achieved in the optical communication band between 0.8 μm and 1.7 μm, and the first zero-dispersion wavelength is in the working wave band of the Ti:sapphire oscillator, which contributes to the frequency conversion of the Ti:sapphire femtosecond laser. PCF with two zero-dispersion wavelengths can make strong power supercontinuum spectral in the near infrared band.

A kind of high birefringence and highly nonlinear nano-structured photonic crystal fibers （N-PCFs） is proposed. The birefringence, fundamental mode field, dispersion and nonlinear characteristics of the fiber have been studied by electromagnetic scattering theory of multipole. It is found that the birefringence becomes larger by increasing the dissymmetry level of fiber core and air holes in cladding, and the largest birefringence reaches up to 1.918×10-2. With this type of high birefringence and highly nonlinear N-PCFs, the peak of birefringence can be moved to the required wavelength by adjusting the pitch value. The non-linear coefficient of N-PCF with pitch 400 nm reaches up to 0.2 m-1·W-1 in the wavelength of 800 nm.Meanwhile, the birefringence value is also very large in the wavelength range of 750—1000 nm. A perfect combination of high birefringence and high nonlinearity is realized in N-PCF. It is useful for manufacturing new type of nano-photonic apparatus and development of integrated optics.

A kind of dual-core high birefringence photonic crystal fibers （DHB-PCFs） has been proposed in this paper. The birefringence， coupling length and dispersion characteristics of DHB-PCFs have been studied by multipole method using mode coupling theory. It is found that the birefringence of DHB-PCF with pitch 1.2 μm and air-hole diameter 1.0 μm is 1.24×10-2 in optical communication band of 1.55 μm wavelength. Correspondingly， dual-core coupling lengths are 21.6 μm and 24.3 μm for x-polarized mode and y-polarized mode， respectively. The DHB-PCF with high degree of polarization and very short coupling length is useful for manufacturing minitype photonic apparatus.

By studying the ultraviolet-red two-color holographic storage performances of Mg-, Zn- and In-doped lithium niobate crystals, we found that the response time of the two-color recording could be shortened by as much as 3 orders of magnitude compared to that of one-color recording, and the two-color recording sensitivity was improved significantly, which was measured to be 11 cm/J in the crystal doped with Mg of 5 mol.%. Nonvolatile holographic storage was achieved in the crystals with doping concentrations above the damage-resistant threshold value. However, gratings on the deep centers and the shallow centers were out of phase in Mg- or Zn-doped lithium niobate, while those in In-doped lithium niobate were in phase. We consider that different defects induced by different dopants are responsible for the observed results.

Absorption spectra, emission spectra, excitation spectra, and upconversion luminescence of Er 3+ , Tm 3+ co-doped NaY(WO 4 ) 2 crystal were measured at room temperature. Intensity parameters are calculated from absorption spectra in terms of Judd-Offelt theory. Transition processes of the energy levels of Er 3+ and Tm 3+ were analyzed in details and the cross relaxations: 1 G 4 (Tm 3+ )＋ 4 I 15/2 (Er 3+ )→ 3 F 4 (Tm 3+ ) + 4 F 9/2 (Er 3+ ) , 1 G 4 (Tm 3+ )＋ 4 I 15/2 (Er 3+ )→ 3 H 5 (Tm 3+ )＋ 4 I 9/2 (Er 3+ ), 3 F 4 (Tm 3+ )＋ 4 I 9/2 (Er 3+ )→ 3 H 6 (Tm 3+ )＋ 4 S 3/2 or 2 H 11/2 (Er 3+ ) and 4 F 9/2 (Er 3+ )＋ 3 H 6 (Tm 3+ )→ 4 I 15/2 (Er 3+ )+ 3 F 3 (Tm 3+ ) were put forward. Sufficient proofs have been found to illustrate the use of Er 3+ as a sensitizer which is effective for the Tm 3+ -doped crystal.

We investigate, by first-principles calculations, the pressure dependence of formation enthalpies and defective geometry and bulk modulus of boron-related impurities (VB, CB, NB, and OB) with different charged states in cubic boron nitride (c-BN) using a supercell approach. It is found that the nitrogen atoms surrounding the defect relax inward in the case of CB, while the nitrogen atoms relax outward in the other cases. These boron-related impurities become much more stable and have larger concentration with increasing pressure. The impurity CB+1 is found to have the lowest formation enthalpy, make the material exhibit semiconductor characters and have the bulk modulus higher than ideal c-BN and than those in the cases of other impurities. Our results suggest that the hardness of c-BN may be strengthened when a carbon atom substitutes at a B site.