感应耦合非热等离子体催化转化二氧化碳

射频感应耦合等离子体能够在室温条件下选择活化并分解二氧化碳，本文通过调控等离子体放电条件(气体流量、放电频率等)获得了较高的一氧化碳产率. 研究发现网状金属催化剂在二氧化碳等离子体中能促进氧原子的复合反应，从而有效抑制其与目标产物一氧化碳的逆反应，提升反应整体效率. 本文为实时转化过剩的可再生电能(来自太阳能、风能、潮汐能等)为高附加值一氧化碳中的化学能提供了一个可行的方案.     

Focus of high-power microwaves with positive and negative zone plate to increase the receiving power in axial virtual cathode oscillator

We investigated an axial vircator, constructed in a pulsed power generator, called Chundoong, and simulated by a three-dimensional particle-in-cell simulation code, MAGIC. We attempted to increase the receiving power of generated microwaves by directing them at a desired focal point. To do so, a positive and negative zone plates (ZPs) are constructed at main frequency 3.5 GHz, and its focal length is 18.8 cm. The power generated from the virtual cathode is 0.72 GW, from which 24.6 kW is received by receiving antenna without a ZP. The receiving power increased significantly to 45.4 kW (92.6%) and 47.5 kW (84.5%) with positive and negative ZPs, respectively. In addition, both positive and negative ZPs have similar focusing properties for the generated microwaves. The ZP contributes significantly to increasing the receiving power. These findings might be useful for real applications to increase the receiving power at a desired focal point.     

Hydrocarbon Formation in the Catalytic Conversion of Methanol Over Zeolite ZSM-5

The reaction mechanism of methanol conversion to hydrocarbons on HZSM-5 zeolite was studied. From the selectivity plots of products in an integral fixed-bed flow reactor, paraffins were classified as primary and secondary stable products, light olefins as primary unstable products, aromatics as primary and secondary unstable or stable products. The results of the ¹⁴C-labelled methanol reaction indicated that the C₁–C₅ surface intermediates generated by dimethyl ether / methanol equilibrium gave paraffins and olefins at 300°C. The concentration of intermediates and adsorbed methanol on ZSM-5 decreased with increasing temperature. The distribution of radioactivity showed that propylene played an important role in the autocatalysis of the reaction.     

甲酰替苯胺异构化的NMR研究

自Ernst1979年创立的二维核磁共振交换谱(2D-EXSY)以来,人们可以仅从一张谱获得复杂体系的动力学信息,勿需用变温等繁琐手段,大大简化了实验.因此该法已在有机化学、金属有机化学及生物化学等领域得到越来越广泛的应用.本文利用前文对2D-EXSY 所做的近似处理方法,对甲酰替苯胺的顺、反异构化进行了研究,并将所得到的结果同线形分析法所得的结果进行了比较,证明本法结果准确、可靠.     

超短脉冲在单块晶体中的三次谐波理论模拟

讨论了群速度失配、自相位调制和交叉相位调制、晶体厚度、基波的频率啁啾等因素对超短脉冲单块晶体的三次谐波转换效率、三倍频光脉冲形状以及频谱的影响.结果表明：群速度延迟使三倍频光脉冲展宽；自相位调制和交叉相位调制会降低转换效率,并使三倍频光脉冲形状发生畸变；晶体厚度对三倍频光脉冲频谱展宽有着较大的影响；合适的基频光频率啁啾可以减小三倍频光脉冲的畸变,并有效地提高三倍频转换效率.     

铝合金稀土转化膜成膜工艺研究

应用正交实验设计 ,开发并研究了LY1 2铝合金 4价铈盐转化膜的成膜工艺及其膜层的耐蚀性能 .实验表明 :经稀土转化处理的铝合金其点蚀电位升高 ,自然腐蚀电位有所降低 ,从而降低了点蚀敏感性 ;试样极化阻力提高 70倍以上 ,耐蚀性能大大提高 ,与铬酸盐相当 ;另外 ,还结合电化学测试和表面分析 ,初步探讨了铝合金稀土转化膜的耐蚀机理     

A high-efficiency solid-state dye-sensitized solar cell with P3HT polymer as a hole conductor and an assistant sensitizer

Poly（3-hexylthiophene） （PBHT） was used in a solid-state dye-sensitized solar cell （S-DSC） with a broad- absorption metal-free organic dye sensitizer 1,2,4,5-benzenetetracarboxylic acid （BzTCA）. Under full- sunlight irradiation （AM 1.5 G, 100 mW/cm2 ）, an overall conversion efficiency of 3.21% was achieved, which represents one of the highest efficiencies reported in an S-DSC. Our results indicate that the P3HT polymer is a promising material as both a hole conductor and an assistant sensitizer in the fabrication of solid-state DSCs.     

Study of Kinetics of Dispersion Polymerization of Styrene in Organic Media

The kinetics of dispersion polymerization of styrene in alcohol/methyl or butyl cellosolve was investigated with dried-weigh methods. The reaction parameters, such as concentration of initiator, polymerization temperature, and solvent, play an important role in determine polymerization rate. It was found that polymerization rate increases with the reaction temperature. The apparent activation energy is of 42.2kJ/mole and 52.6kJ/mole for the initial polymerization stage and the stationary polymerization interval. The polymerization rate increases with the concentration of the initiator with approximately 0.67 order dependence at conversion about 5%. It was described that the relation of conversion with the Hansen Parameters of media in detail by analysis of solvent dispersion, polarity and hydrogen bonding contributions. More significant was the result that polymerization rate versus conversion curve consisted of 3 intervals (2 non-stationary and 1 stationary one). The plateau of polymerization rate was observed in the curve of polymerization rate vs. monomer conversion.     

Study of molybdenum/lanthanum-based composite conversion coatings on AZ31 magnesium alloy

The molybdenum/lanthanum-based (Mo/La) composite conversion coating on AZ31 magnesium alloy was investigated and the corrosion resistance was evaluated as well. The morphology, composition and corrosion resistance of the coating were studied by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and potentiodynamic polarization analysis, respectively. The results revealed that the conversion coating consisted of spherical nodular particles, which was mainly composed of Mo, La, O and Mg. After conversion treatment the corrosion potential shifts about 500 mV positively, and the corrosion current density decreases two orders of magnitude. The corrosion resistance of AZ31 alloy is remarkably improved by Mo/La composite conversion coating.     

Synthesis of Au-CeO2/SiO2 catalyst via adsorbed-layer reactor technique combined with alcohol-thermal treatment

Au-CeO₂/SiO₂ was prepared via adsorbed-layer reactor technique combined with alcohol-thermal treatment. The catalytic performance in complete oxidation of benzene was investigated. TEM, Raman characterization showed that Au particles grew up obviously during alcohol-thermal process, while CeO₂ particles maintained 4 nm in diameter. The content of oxygen vacancies and adsorbed oxygen species on catalysts surface increased apparently. Alcohol-thermally treated Au-CeO₂/SiO₂ and CeO₂/SiO₂ showed similar change in catalytic performance, and were much superior to calcined CeO₂/SiO₂. Of alcohol-thermally treated and calcined CeO₂/SiO₂, initial temperatures of the reaction were 80 °C and 150 °C, respectively. The benzene conversions reached 85% and 40% at 300 °C.