非晶态铁铬合金镀层的研究

实验研究了从三价铬镀液中电沉积非晶态Fe-Cr合金镀层，加入适量的NaF能明显减少并细化镀层的微裂纹。XPS分析说明电沉积初始阶段的蓝膜可能为Cr、Fe以及Cr(OH)3、Cr2O3的混合物，而镀层中的Cr、Fe以单质形式存在。XRD表明镀层相结构与镀层的Cr含量有关，镀层非晶态结构的形成可能是Fe晶格畸变和晶粒细化的综合作用。在(NH4)2CO3和H2SO4溶液中的实验表明非晶态Fe-Cr合金镀层的耐蚀性优于晶态Fe-Cr镀层。     

Reforming of methane with carbon dioxide over supported bimetallic catalysts containing Ni and noble metal: I. Characterization and activity of SiO2 supported Ni–Rh catalysts

Cobalt catalysts supported on silica aerogel have been prepared using sol–gel chemistry followed by drying under supercritical ethanol conditions. Three different loadings of cobalt were synthesized: 2, 6, and 10% by weight. Transmission electron micrographs indicate that the metallic cobalt exists as discrete particles 50–70 nm in diameter for the 2 and 6% loadings. The 10% catalyst shows long needles of cobalt. BET and BJH measurements indicate that the catalysts retain the silica aerogel properties of high surface area (∼800 m²/g), large pore volume (∼5 cm³/g), and an average pore diameter in the mesoporous regime (∼25 nm). The catalysts were evaluated for Fischer–Tropsch activity in a laboratory-scale packed bed reactor. All three catalysts were active with the 10% Co catalyst achieving more than 20% CO conversion which corresponds to a rate of 1.53 g CO per g-cat per hour. The catalysts were selective for the C₁₀₊ hydrocarbons with more than 50% of the carbon contained within this fraction. A significant portion of the C₉–C₁₅ hydrocarbon product was observed as 1-olefins which reflects the enhanced mass transport within the very porous aerogel support.     

离子束加速电压对真空电弧沉积Ti(C,N)涂层性能的影响

利用等离子辅助真空电孤沉积技术分别在高速钢片和单晶硅片制备了Ti(C,N）涂层，通过X-射线衍射和扫描电镜研究了不同离子加速电压对单晶硅片上涂层结构和组织形貌的影响，并测定了高速钢片上涂层的显微硬度，同时进行了耐磨性实验。结果表明：涂层主要由TiN和Ti(C,N）组成，随着离子束加速电压的增大，涂层的沉积速度增大，Ti(C,N）的衍射峰不断宽化，晶格尺寸发生变化，但其表面形貌不受影响；当离子束加速电压为1500V时，涂层有较高的耐磨性和显微硬度，当离子束加速电压为2500V时，涂层的耐磨性和显微硬度都有所下降：     

用2－（5－溴－2－吡啶偶氮）－5－二乙氨基苯光度法测定镍合金镀层中的镧

叙述镧（Ⅲ）－２－（５－溴－２－吡啶偶氮）－５－二乙氨基苯酚（在ＰＶＡ和ＣＰＢ存在下）胶束增溶配合物的特性。ｐＨ＝１０．１时，Ｌａ３＋与２－（５－溴－２－吡啶偶氮）－５－二乙氨基苯酚（在ＰＶＡ、ＣＰＢ存在下）生成１：４的紫红色配合物。配合物最大吸收峰在６０５ｎｍ，其摩尔吸光系数ε为１．０×１０５Ｌ／ｍｏｌ·ｃｍ。该配合物形成稳定常数（ＬＯｇβ）为１５．９。０～８０μｇＬａ３＋／５０ｍＬ，服从朗伯－比尔定律。此法用于测定镍基合金镀层中的镧，结果令人满意。     

铀水冶密实固定床离子交换塔新型反冲出水装置的研制

通过对现有铀水冶密实固定床离子交换塔的反冲出水装置所存在的问题进行分析,提出一种新型反冲出水装置,可有效降低塔内和反冲出水装置所承受压力,达到减少装置泄漏和树脂破损率的目的.     

化学镀镍复合配位剂的研究

采用对比试验和正交试验,以镀速、孔隙率、镀液稳定性和镀层硬度为评价指标,研究了单一配位剂及复合配位剂对镀液和镀层性能的影响,得到了复合配位剂的最优组合:8.4g/L乳酸,6g/L苹果酸,9g/L柠檬酸,8g/L丁二酸,1g/L丙酸。采用该复合配位剂的工艺配方可提高镀液使用寿命,获得性能优良的镀层。     

大坪超大型金矿床铅和硫同位素组成特征及其地质意义

云南大坪超大型金矿床是哀牢山金矿带内最具代表性的金矿床之一,矿体赋存于海西期桃家寨闪长岩体内,矿石类型以石英脉型为主,与金伴生的是以黄铁矿、方铅矿为主的各种硫化物。本文对该矿床主成矿阶段石英脉型矿石中方铅矿的铅、硫同位素地球化学特征开展了系统研究,结果表明：大坪金矿床主成矿阶段铅同位素具有较窄的206Pb/204Pb值和相对较高的207Pb/204Pb值及208Pb/204Pb值,但变化范围不大,分布于正常铅范围。通过计算获得相关特征参数,利用铅构造模式图及相关图解综合分析,表明矿石铅为壳幔混合铅;硫同位素组成变化范围为-4.9‰-9.2‰,平均值为3.12‰,偏离陨石硫的范围,而与基性岩类的硫同位素组成非常接近,表明硫主要来源于深部,反映了地幔硫遭受地壳物质混入后的硫同位素组成。该矿床的成矿物质为深部幔源物质混合了壳源物质。     

中国典型脉型钨、锡矿床和斑岩钼矿流体包裹体特征

中国脉型钨、锡矿床和斑岩钼矿无论在时空分布上还是在成矿特征上都有很大的相似性。本文以几个典型矿床为例,从流体包裹体角度对比分析了其成矿特征的异同。根据流体包裹体的组合类型、气液比等特征可以大致推断出成矿温度。流体成分与岩浆的侵入深度之间存在着近似相关关系。随着成矿过程的进行,流体温度和盐度逐渐降低,钨、锡流体特征非常相似,但锡矿床的盐度略高于钨矿床。斑岩钼矿的盐度非常高,这是典型的次火山体系的流体特征,压力影响着成矿温度及流体成分。流体成分上锡矿床CO2含量明显要高于钨矿床,而且F的含量较高,斑岩钼矿床由于其源区物质成分的差异导致流体具有不同的特征。流体沸腾、混合及自然冷却是流体演化的3个过程,其中流体沸腾对成矿意义重大。CO2是挥发份中的常见组分,能影响流体不混溶的发生条件。     

锅炉水冷壁沉积物较多原因分析

介绍了某电厂锅炉水冷壁沉积物较多的基本情况。通过对沉积量和沉积物成分进行分析检测、对机组水汽品质进行查定和对锅炉燃烧工况等情况的分析认为:给水溶解氧的长期不合格导致省煤器等部位的氧腐蚀是造成锅炉水冷壁沉积物较多的主要原因。     

Electrodeposition of nickel in the presence of Al<Superscript>3+</Superscript> from sulfate baths

The effect of Al³⁺ on the cathodic current efficiency, deposit morphology, crystallographic orientations and polarisation behaviour of the cathode during electrodeposition of nickel from acidic sulfate solutions was investigated. Higher concentration of Al³⁺ (>10 mg dm^–3) significantly deteriorated the surface quality of the nickel deposit as well as the current efficiency. X-ray diffraction studies revealed that the (200) plane was the most preferred crystal plane and was not affected by the presence of varying concentration of Al³⁺ in the electrolytic bath. The presence of Al³⁺ caused polarisation of the cathode, which increased with increasing Al³⁺ concentration. The effect of Al³⁺ on the electrokinetic parameters: Tafel slope (b), transfer coefficient () and exchange current density (i₀) were also investigated.