从水淬渣中回收镓的试验研究

对鼓风炉（ISP法）或烟化炉水淬渣中回收镓的工艺进行了研究。结果表明，利用浓硫酸恒温熟化的独特浸出工艺，克服硅对液固分离的影响；以伯胺N9123作为萃取剂在硫酸介质中萃取镓；获得了含镓品位为2.82%的富集物。     

钛铁矿流态化氧化机理研究

对低品位钛铁矿进行预氧化、预还原等预处理后可满足硫酸法生产钛白粉工艺所需高品位钛铁矿的要求。本试验采用流态化预氧化方法处理风化程度低、含硫较高的钛铁矿。结果表明 :流态化氧化可大幅度地降低钛铁矿中硫含量 ;钛铁矿流态化氧化的适宜温度为 :80 0～ 90 0℃ ,且在此温度范围内 ,随温度的升高 ,钛铁矿的氧化速度增加 ,在 90 0℃时 ,5 0min钛铁矿基本能完成氧化     

硫化矿石氧化性的实验室综合评判

探讨了一种硫化矿石氧化性综合评判的新方法 ,并将该方法应用于矿山实际 ,得到了准确的评判结果。该项成果对于硫化矿石自燃防治理论与技术的研究具有很高的参考价值。     

Rutile-type TiO2 thin film for high-k gate insulator

We investigated rutile-type titanium dioxide (TiO₂) films for possible use as a high-k gate insulator. The TiO₂ thin films were directly deposited on Si substrates using a RF magnetron sputtering method with a sintered oxide target. A single phase of rutile-type TiO₂ whose dielectric constant of approximately 75 was obtained when the film was deposited in an inert gas atmosphere and annealed at 800 °C in an oxidizing gas atmosphere. The oxygen ions were deficient in the as-deposited film, and consequently, a sufficient oxygen supply was needed to crystallize the film to a single phase of rutile during the post-annealing. However, the interfacial SiO₂ layer between the TiO₂ and the Si substrate simultaneously grew thicker than 2 nm. As the interfacial SiO₂ grew, the leakage current was decreased and the equivalent oxide thickness was increased, in the Au/rutile-type TiO₂/Si capacitor. Therefore, we concluded that the growth of the interfacial SiO₂ layer thicker than 2 nm is inevitable to form the single phase of rutile-type TiO₂ and to decrease the leakage.     

Microstructure and properties of MoSi2–MoB and MoSi2–Mo5Si3 molybdenum silicides

MoSi₂-based intermetallics containing different volume fractions of MoB or Mo₅Si₃ were fabricated by hot-pressing MoSi₂, MoB, and Mo₅Si₃ powders in vacuum. Both classes of alloys contained approximately 5 vol.% of dispersed silica phase. Additions of MoB or Mo₅Si₃ caused the average grain size to decrease. The decrease in the grain size was typically accompanied by an increase in flexure strength, a decrease in the room temperature fracture toughness, and a decrease in the hot strength (compressive creep strength) measured around 1200 °C, except when the Mo₅Si₃ effectively became the major phase. Oxidation measurements on the two classes of alloys were carried out in air. Both classes of alloys were protected from oxidation by an in-situ adherent scale that formed on exposure to high temperature. The scale, although not analyzed in detail, is commonly recognized in MoSi₂ containing materials as consisting mostly of SiO₂. The MoB containing materials showed an increase in the scale thickness and the cyclic oxidation rate at 1400 °C when compared with pure MoSi₂. However, in contrast with the pure MoSi₂ material, oxidation at 1400 °C began with a weight loss followed by a weight gain and the formation of the protective silica layer. The Mo₅Si₃ containing materials experienced substantial initial weight losses followed by regions of small weight changes. Overall, the MoB and Mo₅Si₃ additions to MoSi₂ tended to be detrimental for the mechanical and oxidative properties.     

Epoxidation of olefines with PDMS membranes containing zeolite occluded manganese diimine complexes

A new composite catalyst for selective epoxidation of olefins with tert-butyl hydroperoxide (tBHP) is reported. The catalyst contains manganese diimine complexes (cis-Mn bis-2,2′-Bipyridyl), occluded within a NaY zeolite, in turn incorporated in a polydimethylsiloxane membrane (cis-[Mn(bpy)₂]²⁺-NaY-PDMS). The three-step synthesis consists of a Mn²⁺exchange of NaY, ligand sorption to form cis-[Mn(bpy)₂]²⁺-NaY and incorporation of the latter in a PDMS membrane. The major differences between [Mn(bpy)₂]²⁺-NaY as such and occluded in PDMS are observed in the sorption and catalytic characteristics. With the membrane system, the use of a solvent becomes obsolete. Whereas optimal cyclohexene oxidation with [Mn(bpy)₂]²⁺-NaY occurs with hydrogen peroxide in acetone, tBuOOH proves to be a better oxidant for [Mn(bpy)₂]²⁺-NaY-PDMS. The reactions in batch and fed-batch reactors are discussed. A simple regeneration procedure, monitored by FT-IR spectroscopy is proposed.     

某含砷浮选金精矿的细菌氧化预处理-氰化提金试验研究

云南省某含砷难浸金精矿，常规氰化金浸出率仅为26．17％，通过采用细菌氧化预处理后，金浸出率达到98．25％，获得了非常理想的试验指标。     

糠醛装置腐蚀机理分析及防护

重质糠醛精制装置设备腐蚀严重与糠醛氧化变质有关,通过分析装置设备腐蚀机理和糠醛氧化、变质的原因,提出了用N_2汽提回收和原料脱水等改进措施。     

Oxidation behavior of silicide coating on Ti3SiC2-based ceramic

A silicide coating was prepared on Ti₃SiC₂-based ceramic by pack cementation to improve the oxidation resistance of Ti₃SiC₂, which is a technologically important material for high temperature applications. The microstructure, phase composition and oxidation resistance of the coated sample were investigated. The results demonstrated that the silicide coating was mainly composed of TiSi₂ and SiC. A single layer of a mixture of SiO₂ and TiO₂ was formed on the surface of the coated sample during isothermal oxidation at 1100 °C and 1200 °C for 20h. Compared to Ti₃SiC₂, the parabolic rate constant of silicide coated Ti₃SiC₂ decreased by 2~3 orders of magnitude. Furthermore, the coated sample showed much better cyclic oxidation resistance than Ti₃SiC₂ during the cyclic oxidation at 1100 °C for 400 times. However, during the preparation of the coating, a number of fine cracks formed in the outer layer of the coating. When these cracks penetrated the whole coating during the cyclic oxidation, the oxidation rate was accelerated, which degraded the oxidation resistance. Electronic Publication     

纳米ZnO薄膜制备及液态源掺杂

用真空蒸发法在玻璃和单晶硅片 (10 0 )上制备Zn薄膜 ,然后对Zn薄膜进行氧化、热处理获得纳米ZnO薄膜。对在硅片上制备的Zn薄膜一次性进行高温掺杂、氧化获得纳米ZnO∶P和ZnO∶B薄膜。研究不同氧化、掺杂温度和时间对薄膜结构、电学性能的影响。结果表明 :氧化温度和时间对ZnO薄膜结构影响较大 ,液态源掺P可明显改善纳米ZnO薄膜的导电性能、结构特性和化学组分