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In this paper, the fly ash cenosphere was coated evenly on the surface with Ni–P alloy in chemical plating method. The coated cenosphere was used for coating as filler, and its heat insulation performance and absorbing performance was tested. The results show that the cenosphere chemical nickel plating material complex dielectric constant is bigger than complex permittivity in both real part and imaginary part. The imaginary part of complex permeability is close to zero, which means it belongs to the electromagnetic loss type materials. e″ appeared the maximum 20·3 when the frequency is 4 GHz. We tested the cenosphere heat insulation coating with self-made heat insulation device. The temperature difference between back coating at balance point and the blank sample reached 10°C, indicating obvious heat insulation effect.

In this paper, we produced spinel structure nanometre cobalt blue powder pigment by chemical coprecipitation. We also modified it through element doping and analysed the spinel structure and colouring mechanism of the pigment. We discussed the process conditions of coprecipitation reaction, the influence of doping element and its content on the properties of cobalt blue pigments spectral reflection effect. The morphology and particle size of powders were characterised through scanning electron microscopy and energy dispersive spectroscopy. The doping element type and content have great influence on the spectral curve of the cobalt pigment. High temperature in sintering contributes to the performance of the products. The sample produced at 1250°C sintering possesses good reflection characteristics, which is similar to chlorophyll.

We present what is, to the best of our knowledge, the first diode-pumped Nd:La3Ga5SiO14 (Nd:LGS) laser emitting at 888 nm, based on the 4F3/2-4I9/2 transition, generally used for a 904 nm emission. The use of a pump module with 16 passes through the crystal allowed the realization of a Nd:LGS thin-disk laser with 1.41 W of continuous wave (cw) output power at 888 nm. Moreover, intracavity second-harmonic generation (SHG) in cw mode has also been demonstrated with a power of 221 mW at 444 nm by using a BiB3O6 (BiBO) nonlinear crystal.

We report for the first time a continuous-wave (CW) yellow laser emission by sum-frequency mixing in Nd:YAG crystal. Using type-I critical phase-matching LBO crystal, a yellow laser at 572 nm is obtained by 1444 and 946 nm intracavity sum-frequency mixing. The maximum laser output power of 178 mW is obtained when an incident pump laser of 18.2 W is used. At the output power level of 178 mW, the output stability is better than 4.2%.

A dual-wavelength continuous-wave (CW) diode-pumped Nd:YVO4 laser that generates simultaneous laser action at the wavelengths 914 and 1342 nm is demonstrated. A total dual-wavelength output power of 1.79 W was achieved at the incident pump power of 18.2 W. Furthermore, intracavity sum-frequency mixing at 914 and 1342 nm was then realized in a LBO crystal to reach the yellow-green range. We obtained a total CW output power of 212 mW at 544 nm.

We report for the first time a continuous wave (CW) coherent radiation at 611 nm by intracavity sum-frequency generation of 1064 nm Nd:YVO4 laser and 1433 nm Nd:YAP laser. Red-orange laser is obtained by using a doubly cavity, type-II critical phase matching KTP crystal sum-frequency mixing. With total pump power of 27.9 W (17.8 W pump power for 1433 nm Nd:YAP laser and 10.1 W pump power for 1064 nm Nd:YVO4 laser), TEM00 mode red-orange laser at 611 nm of 1.15 W is obtained. The red-orange power stability in 30 min is better than 4.3%.

The use of nanoparticles on thin-film solar cells is an effective way to enhance optical absorption. A simulation is presented of a three-dimensional array of cylindrical Ag nanoparticles on the surface of a solar cell, which has been proved very efficient to enhance the optical absorption of the silicon substrate by utilizing localized surface plasmons. The enhancement ratio has been simulated with respect to nanoparticle radius and height as well as crystalline silicon substrate thickness and is discussed in detail. The absorption enhancements were found to exhibit a damping oscillation when only height or thickness of the cylindrical nanoparticle were varied. Even without intentional optimization, an enhancement factor of 1.283 for a silicon substrate with a thickness of 500 nm was still achieved in our simulations. A further optimized structure has the potential to attain a higher factor.

Based on the gasoline direct-injection spark ignition (DISI) engine technologies and methanol fuel characteristics, a complex-guided multi-hole spray coupled with induction swirl and chamber-wall-guided stratified-charge combustion system for a DISI methanol engine was developed. It was retrofitted from a four-cylinder diesel engine with a compression ratio of 14. It was developed to run on methanol in stratified-charge and homogeneous-charge combustion modes; under part-load operating conditions, stratified-charge combustion is adopted to improve fuel economy while, under high- and full-load conditions, the homogeneous-charge combustion mode is adopted for the purpose of a higher power output. Under both combustion modes, the key parameters of the combustion system were matched and optimized respectively. The operating map for both combustion modes was obtained. Then, the engine power performance, emissions, and combustion characteristics were studied. The power output of the developed methanol engine is higher than that of the original diesel engine. By using the stratified combustion mode under low-load conditions, the engine fuel economy (the brake thermal efficiency) is improved; the stratified-charge combustion of methanol performed relatively well with acceptable values of the coefficient of the cyclic variation in the indicated mean effective pressure. The smoke and nitrogen oxide emissions from the DISI methanol engine are both reduced simultaneously and significantly.

On the basis of the wall-guided, spray-guided, and air-guided technologies related to gasoline direct-injection spark-ignition (DISI) engines, a complex-guided stratified-charge combustion system for a methanol DISI engine was developed. The test engine was a retrofitted four-cylinder diesel engine. The key parameters were optimized numerically and experimentally, such as the location of the swirl deflector, the spatial location of spray, the swirl ratio, the injection and ignition timings, and the needle valve opening pressure. The results show that the direct-injection stratified-charge (DISC) methanol engine can work with an excessive air ratio λ as high as 2.23, and its brake thermal efficiency reaches 29.7 per cent at a speed of 1500r/min, and a brake mean effective pressure of 0.45MPa. The DISC methanol engine exhibits relatively good performance with little cyclic variations, although it is sensitive to induction swirl. The test results indicate that the matching principle is successful. The developed DISC methanol engine can run under variable induction swirl to meet the requirement of stratification combustion under different engine speed operating conditions.

We report for the first time a continuous-wave (CW) blue-green laser emission by sum-frequency mixing in Nd:CNGG crystal. Using type-I critical phase-matching LBO crystal, a blue-green laser at 497 nm is obtained by 1061 and 935 nm intracavity sum-frequency mixing. The maximum laser output power of 232 mW is obtained when an incident pump laser of 18.2 W is used. At the output power level of 232 mW, the output stability is better than 3.67%. The beam quality M2 value is are about 1.26 and 1.38 in both horizontal and vertical dimensions respectively.

We report for the first time a continuous-wave (CW) blue laser emission by sum-frequency mixing in Nd:LuVO4 crystal. Using type-I critical phase-matching (CPM) LBO crystal, a blue laser at 493 nm is obtained by 1066 and 916 nm intracavity sum-frequency mixing. The maximum laser output power of 520 mW is obtained when an incident pump laser of 18.2 W is used. At the output power level of 520 mW, the output stability is better than 2.8%. The beam quality M2 value is are about 1.22 and 1.31 in both horizontal and vertical dimensions respectively.

It is reported that efficient continuous-wave (CW) red laser generation at 693 nm in a LBO crystal at type-I phase matching direction performed with a diode-pumped Nd:YVO4 laser. With incident pump power of 18.2 W, output power of 278 mW at 693 nm has been obtained using a 10 mm-long LBO crystal. At the output power level of 278 mW, the output stability is better than 2.9%.

A diode-end-pumped continuous-wave (CW) simultaneous dual-wavelength laser operation at 1062 and 1331 nm in a single Nd:GGG was demonstrated. A total output power of 1.08 W at the two fundamental wavelengths was achieved at the incident pump power of 18.2 W. The optical-to-optical conversion is up to 5.9% with respect to the incident pump power. To the best of our knowledge, this is first work on CW simultaneous dual-wavelength operation of a diode pumped Nd:GGG laser. The article is published in the original.)

We describe the output performances of the 1048 nm transition in Yb:YAG under in-band pumping with diode laser at the 968 nm wavelength. An end-pumped Yb:YAG crystal yielded 787 mW of continuous-wave (CW) output power for 9.1 W of absorbed pump power. Furthermore, 104 mW 524 nm green light was acquired by frequency doubling. Comparative results obtained for the pump with diode laser at 940 nm are given in order to prove the advantages of the in-band pumping.

A dual-wavelength continuous-wave (CW) diode end-pumped Nd3+:YAlO3 (Nd:YAP) laser that generates simultaneous laser action at the wavelengths 930 and 1341 nm is demonstrated. A total output power of 778 mW for the dual-wavelength was achieved at the incident pump power of 17.8 W. Furthermore, intracavity sum-frequency mixing at 930 and 1341 nm was then realized in a LBO crystal to reach the yellow-green range. We obtained a total CW output power of 103 mW at 549 nm.

A dual-wavelength continuous-wave (CW) diode end-pumped Nd3+:YAlO3 (Nd:YAP) laser that generates simultaneous laser action at the wavelengths 1064 and 930 nm is demonstrated. A total output power of 2.15 W (1.57 W at 1064 nm and 0.58 W at 930 nm) for the dual-wavelength was achieved at the incident pump power of 17.8 W with optical conversion efficiency of 12.1%. The M2 values for 930 and 1064 nm lights were found to be around 1.21 and 1.32, respectively.

Radiation polymerization of N-vinylcarbaozle (VCz), in benzene solutions, in vacuum or nitrogen-bubbled at different concentrations was carried out by 60Co γ-ray radiation at a dose rate of 10.5 kGy/h. Unlike other vinyl compounds, VCz polymerizes at a higher radiation dosage; however, the side groups of carbazole are not eliminated from their sites. Gel permeation chromatography was used to characterize molecular weight and distribution. Oxidation was found only when polymerization was conducted using nitrogen-bubbled solutions at lower concentration of VCz. The optimization to polymerize VCz was obtained based on the dependence of polymer yield on radiation dosage. Single layer electroluminescent device based on commercially radically polymerized poly(N-vinylcarbazole) shows inferiority in luminance and efficiency, due to electronic traps resulted from heterogeneous end groups, when compared with that based on radiation-polymerized PVCz free of heterogeneous end groups. The effect of the different end groups may be confirmed by the divergent morphology when PVCz thin films were annealed above glass transition temperature (Tg).

The abilities to trigger and guide high-voltage discharge by using single andemmultiple filaments/em(MFs) are experimentally studied. It is shown that the discharge voltage threshold can be reduced significantly in both regimes of single and MF; however, the MF does not gain a larger reduction than a single filament. This behavior of the MF is attributed to the single discharge path rather than simultaneous multiple ones as one might expect during the discharge process.

A zero-voltage switching DC/DC converter with the high circuit efficiency is presented in this paper. The structure of a full-bridge converter with the phase-shift PWM is used to achieve the zero-voltage switching in the transformer primary side for the purpose of the switching lose reduction. In order to increase the converter efficiency in the transformer secondary side, a current doublers rectifier, low current ripple, and synchronized rectifier circuits are also adopted. The detail circuit operation and mathematical analysis are presented in this paper. The measured efficiency on the prototype, a DC/DC converter 200V/24V with 6A output current, is higher than 88%.

It is regarded as an effective method to improve the flux pinning performance by the additives of the secondary phase inclusions in nano sizes into high temperature superconductor bulks. We prepared the single domain superconductor GdBa2Gi3O7-δ bulks with variable additions of (ZrO2+SnO2+ZnO) nano-particles in air by using top seed melt-textured growth process. The effect of nano-particle additions on superconductivity properties has been investigated. An enhancement of the critical current JC in low and intermediate field at 77K and trapped field was discovered by the additions of the nano-particles. At the same time, the superconductor transition temperature, TC, slightly decreases from 93.5K to 91.5K The microstructure measurements show that the nano-particle inclusions enhance with the increase of the content of nano-particles, which may illuminate the JC enhancement of the specimens.

Titanium silicide films cosputtered on a polycrystalline silicon layer over a thermally oxidized silicon wafer were rapidly annealed at various temperatures and times using a graphite strip heater. Sheet resistances comparable with those of furnace annealed samples were obtained using 45‐sec anneals at 1000–1200 °C. X‐ray diffraction revealed only the formation of a TiSi2 phase, but Rutherford backscattering showed that the amount of excess silicon beyond stoichiometric TiSi2 increased with increasing anneal temperature. Significant increases in the infrared reflectivity spectrum were observed upon annealing which suggests that front side annealing may result in better thermal uniformity across a wafer.

Three MOS gate structures; polysilicon, tungsten silicide and tungsten polycide, were fabricated and their workfunctions measured with the high frequency C-V technique. The work functions were 4.14 ev and 4.82 ev for phosphorus doped polysilicon and silicon-rich tungsten silicide, respectively. The tungsten polycide structure, however, showed a variance between 4.14 ev and 4.38 ev for different experiments. The polycide MOS device threshold was about 0.15 volt higher than that of polysilicon. Phosphorus out-diffusion and tungsten diffusion along polysilicon grain boundaries were postulated to explain this phenomenon.

Sheet resistance and Hall effect measurements were made on graphite strip isothermally annealed antimony implanted (100) and (111) silicon. Although the (111) silicon annealed at lower temperatures, the (100) silicon achieved a lower sheet resistance (∼40 Ω/⧠ for a 3.8×1015 cm−3 dose) due to a greater activated carrier surface density. Supersaturated solid solutions were observed for both surfaces. At high active carrier concentrations (≳1×1020 cm−3), the rapid decrease of mobility with increasing carrier concentration is attributed to ionized impurity scattering.

The electrical transport properties of cosputtered tungsten silicide films were investigated. The microstructure of the annealed film was determined by x‐ray diffraction. Both resistivity and Hall coefficients for the WSi2 films were measured in the temperature range 80–300 K. The current carriers in tungsten disilicide were found to be positive holes. The carrier concentration determined from this experiment is ∼1×1022 cm−3 which does not change with either annealing process or measuring temperature. The resistivity of the WSi2 film in the measured temperature range increases approximately linearly with temperature. The carrier mobility and its temperature dependence were also studied.

Silicon‐poor tantalum silicide films cosputtered on polycrystalline silicon over thermal oxide on silicon were rapidly annealed for various temperatures and times using a graphite strip heater. Rutherford backscattering and x‐ray diffraction showed rapid formation of a stoichiometric tantalum disilicide via Si diffusion from the polycrystalline Si. This was accompanied by significant grain growth and a reduction in resistivity. Sheet resistances comparable with those of furnace‐annealed samples were obtained.