配煤法制备中孔活性炭的试验研究

以不同配比的大同烟煤和太西无烟煤为原料，不同配比的碱式碳酸镁和硝酸铵作为添加剂，在不同的炭化温度和活化时间下制备活性炭。试验结果表明：高含量的大同烟煤、碱式碳酸镁和硝酸铵的比值为1：2、600℃的炭化温度更有利于制备中孔丰富的活性炭。     

黄磷尾气净化脱除磷化氢、硫化氢中试试验

采用自制的催化剂JC-4,设计出碱洗-催化氧化工艺对黄磷尾气进行深度净化处理。中试试验结果表明:常压、100℃、尾气流量为36~50 m3/h、氧气体积分数为1.2%~1.5%时,PH3的脱除率接近100%,出口质量浓度低于1.0 mg/m3;碱洗单元可以除去90%的H2S,经过催化氧化单元可以进一步脱除H2S,净化效率接近100%,出口质量浓度低于1.0 mg/m3;催化剂经100~200 h需要再生,400 h后需要活化,再生和活化处理后的催化剂性能良好。     

Tensile properties of long aligned double-walled carbon nanotube strands

The mechanical properties of well-aligned double-walled carbon nanotube (DWNT) strands with diameters of 3-20 μm and lengths of ∼10 mm were measured using a stress-strain puller. The average tensile strength and Young’s modulus of the tested strands are 1.2 GPa and 16 GPa, respectively. Deformation and fracture processes of these samples are discussed. The tensile strength and Young’s modulus of an individual DWNT bundle were estimated, with values comparable to those of SWNT bundles. The superior mechanical strengths of our as-prepared DWNT strands are expected to give them potential as a high-strength material and a reinforcement in composites.     

Dynamic response of Ti3SiC2 under shock compression up to 112 GPa

Ti₃SiC₂ is of interest due to its unique dual nature reminiscent of both brittle ceramics and ductile metals at ambient conditions. In this work, plate-impact experiments have been performed to study the dynamic behavior of Ti₃SiC₂ under shock compression up to 112 GPa by using laser velocity interferometer and electric pin techniques. Hugoniot elastic limits (HEL), spall strength, and Hugoniot equations of state have been obtained based on measured particle velocity profiles and shock wave velocities. The ratio of spall strength to HEL for Ti₃SiC₂ is larger than brittle ceramics but smaller than metals. This result indicates that the dual nature of Ti₃SiC₂ remains at least up to 10 GPa. On the other hand, the linearity of the Hugoniot equation of state, $D=6.9\text{0}1(22)+1.153(53)u_{\text{p}}$, suggests that the initial structure of Ti₃SiC₂ should be stable up to 112 GPa, in contrast to the result reported by Jordan et al. [J. Appl. Phys., 93 (2003) 9639].     

关于大学学习分类的研究与探索

本文首先比较仔细地分析了几种具有重要影响的学习分类理论,即联想学习、奥苏贝尔意义学习、布鲁姆教育目标分类学中关于学习的分类、加涅对学习结果的五种分类等,并分析了四者之间的联系和区别,以及学习分类理论的发展趋势.在此基础上提出了大学学习的主要内涵,并据此将大学学习划分为程序性知识、陈述性知识、认知策略、动作技能、情感五类结果.     

关于化工工艺学教学改革的探讨

本文从强化课堂教学、加强实践与理论教学相结合以及强化学生工程观念等方面对《化工工艺学》课程教学方法的改革进行了探讨,提高了教学质量和教学效果,为更好地培养具有较强综合能力的化工工艺专业合格人才提供了重要保证。     

硬盘用基板微晶玻璃的研究与应用

介绍了适用于高容量、小型化硬盘用基板的各种微晶玻璃材料，简要讨论了各种微晶玻璃的化学组成、显微结构、主晶相种类以及各种微晶玻璃的特性，并对今后的发展趋势进行了展望。     

4-(2-噻吩基)苯乙酸及其衍生物的合成

采用新方法设计并合成了4-(2-噻吩基)苯乙酸及其衍生物。通过对各步反应的研究,找到了最佳的反应条件和4-(2-噻吩基)苯乙酸及其衍生物的分离和纯化方法。并对这些化合物的结构用元素分析I、R1、H NMR进行了确证。并对其潜在的应用价值进行了探讨。     

海外瞭望

Naturex收购HP植物制剂公司Naturex公司(Avignon,法国)宣布收购意大利HP植物制剂公司(米兰)。Naturex是一家植物萃取物供应商,最近曾收购了位于米兰的HammerPharma公司。HP植物制剂公司主要致力于营养保健品行业中所用到的植物萃取物的配方设计及销售。对于这一收购行动,Naturex公司总裁兼首席执行官Jacques Dikansky说:“两家公司的联合将使我们同目前已有的意大利客户之间的联系更为紧密,并有助于我们扩大这一市场,使其在整个欧洲市场具有战略意义。”芬美意收购丹尼斯克食用香精业务芬美意公司(日内瓦)已同意以33.6亿丹麦克朗的价…     

Preparation and characterization of multi-walled carbon nanotubes supported PtRu catalysts for proton exchange membrane fuel cells

A series of PtRu nanocomposites supported on H₂O₂-oxidized multi-walled carbon nanotubes (MWCNTs) were synthesized via two chemical reduction methods—one used aqueous formaldehyde (HCHO method) and the other used ethylene glycol (EG method) as the reducing agents. The effects of the solvents (water and ethylene glycol) and the surface composition of the MWCNTs on the deposition and the dispersion of the metal particles were investigated using N₂ adsorption, TEM, ICP-AES, FTIR and TPD. The wetting heats of the MWCNTs in corresponding solvents were also measured. The characterizations suggest that combination of the surface chemistry of the MWCNTs with the solvents decides the deposition and the dispersion of the metal nanoparticles. These nanocomposites were evaluated as proton exchange membrane fuel cell anode catalysts for oxidation of 50 ppm CO contaminated hydrogen and compared with a commercial PtRu/C catalyst. The data reveal superior performances for the nanocomposites prepared by the EG method to those by the HCHO method and even to that for the commercial analogue. Structure–performance relationship of the nanocomposites was also studied.