21世纪新玻璃的发展

新玻璃是指与传统玻璃相比具有不同性质、功能和用途,或采用与传统玻璃不同的成分、原料和制备工艺而得到的玻璃材料及制品.在以信息技术为主导、多门高新技术为支柱的新经济时代,新玻璃主要用于信息技术、生命科学、新能源与再生能源、新材料、海洋科学、环境保护方面.本文阐述了新玻璃的特征、品种、制备与发展.     

两种沥青炭微观结构和性能的对比研究

将高温煤沥青和浸溃荆沥青在92MPa下炭化，在2500℃下对所得沥青炭进行石墨化处理；测试了所得沥青炭的体积密度、开孔率、比表面积（SBET）；利用扫描电子显微镜（SEM）观察了所得沥青炭的显微结构；利用X射线衍射方法（XRD）检测了所得沥青炭石墨化处理后的石墨化度；测试了所得沥青炭的氧化性能；测试了沥青炭试样的比热容、导热系数、热扩散率和线膨胀系数。结果表明：在92MPa下，两种沥青炭有着相近的密度和开孔率；浸渍剂沥青炭的SBEt高于高温煤沥青炭；浸渍荆沥青炭为流线型结构，高温煤沥青炭为镶嵌型和域型并存的结构；流线型结构沥青炭石墨化度较高；高温煤沥青炭的抗氧化性能要好于浸溃荆沥青炭；随着沥青炭石墨化程度的增大，比热客、导热系数、热扩散率都增大，而线膨胀系数减小。     

Role of La2O3 in Pd-Supported Catalysts for Methanol Decomposition

Systems of Pd supported on various La₂O₃-modified -Al₂O₃ and CeO₂–Al₂O₃ catalysts were tested for catalytic methanol decomposition and characterized by means of XRD, BET, TPR, H₂-chemisorption and CO–FTIR. The addition of lanthanum significantly improved the selectivity of CO and H₂ for all the catalysts but showed a different influence on the catalytic activity in two systems. Methanol conversion decreased on La₂O₃-modified Pd/-Al₂O₃ catalysts, in line with the reduction of Pd dispersion, while the addition of La₂O₃ improved the dispersion of Pd and reinforced Pd–CeO₂ interaction for La₂O₃-modified Pd/CeO₂–Al₂O₃ catalysts, which resulted in a high production rate of CO and H₂. Thus, a synergistic effect between CeO₂ and La₂O₃ was observed on -Al₂O₃-supported Pd catalyst for methanol decomposition.     

Application of supercritical fluid chromatography in the quantitative analysis of minor components (carotenes,vitamin E,sterols, and squalene) from palm oil

The application of supercritical fluid chromatography (SFC) coupled with a UV variable-wavelength detector to isolate the minor components (carotenes, vitamin E, sterols, and squalene) in crude palm oil (CPO) and the residual oil from palm-pressed fiber is reported. SFC is a good technique for the isolation and analysis of these compounds from the sources mentioned. The carotenes, vitamin E, sterols, and squalene were isolated in less than 20 min. The individual vitamin E isomers present in palm oil were also isolated into their respective components, α-tocopherol, α-tocotrienol, γ-tocopherol, γ-tocotrienol, and δ-tocotrienol. Calibration of all the minor components of palm as well as the individual components of palm vitamin E was carried out and was found to be comparable to those analyzed by other established analytical methods.     

Fabricating Water-Insoluble Polyelectrolyte into Multilayers with Layer-by-layer Self-assembly

Summary A water insoluble azo-containing polyelectrolyte (PEAPB6P-AC) was successfully fabricated into multilayer films based on the layer-by-layer adsorption technique by using N, N-dimethylformamide (DMF) as the assembling media. The multilayer growth and structure were studied with UV-vis spectroscopy, and the multilayer surface were imaged with Atomic Force Microscopy and compared with that fabricated in water. The results show that assembling PEAPB6P-AC in DMF can effectively eliminate the hydrophobic aggregation of the azo units and consequently results in a much smoother multilayer surface than that fabricated in water. This improvement to the layer-by-layer adsorption technique, which can avoid some major difficulties faced when assembling hydrophobic polyelectrolytes in aqueous solutions, seems to be a versatile way to fabricate high quality multilayer films when using the hydrophobic even water-insoluble polyelectrolytes as assembling units.     

Mass production of high-quality multi-walled carbon nanotube bundles on a Ni/Mo/MgO catalyst

A new catalyst (Ni/Mo/MgO) is reported, with which one can synthesize multi-walled carbon nanotube (MWNT) bundles with a yield of more than 45 times the amount of the pristine catalyst, using a methane-hydrogen mixture as precursor. Powder X-ray diffraction, Raman spectroscopy and thermal gravimetric analysis show that the purity of the as-prepared MWNTs is over 97%. The diameter of the carbon nanotubes is 9-20 nm, measured by high-resolution electron microscopy on 421 individual MWNTs. The high purity of the as-prepared MWNTs allows us to omit the usual complex purification process required for carbon nanotubes synthesized by chemical vapor deposition. Because of its durable high activity, the Ni/Mo/MgO catalyst in its pristine state is ideal for mass production of high-quality MWNTs. The synergism of nickel and molybdenum is considered the main reason for the high yield of carbon nanotubes.     

影响聚氨酯弹性体紫外线稳定性的因素

介绍了聚氨酯弹性体在紫外线照射下发生光老化的反应机理及其软段、硬段种类和结构对弹性体紫外线稳定性的影响,探讨了光稳定剂、光屏蔽剂对弹性体耐紫外线稳定性的影响。     

Al2O3-SiC-C质主铁沟浇注料的结合相研究

对高炉主出铁沟用Al2O3-SiC-C质浇注料的结合相变化进行了分析，其中涉及到溶胶结合、氮化硅铁为添加物形成的sialon结合、水泥形成的水硬性结合。溶胶结合强度主要来自于化学结合；而sialon结合、水泥结合的强度仍然来自少量水泥形成的水硬性凝固相的作用，因此对烘烤工艺、使用效果的影响不同。     

The effect of Al content on the wettability between liquid iron and MgOAl2O3 binary substrate

In the present study, the wettability between liquid iron with two different Al contents and MgOAl₂O₃ binary substrates was studied in reducing atmosphere. The contact angles between liquid iron with 18?ppm Al and MgO, MgO·Al₂O₃, Al₂O₃ were 133.5°, 113.7°, 126.9° respectively. With the variation of the substrate composition, the contact angles for the intermediate binary phases of the three components (MgO, MgO·Al₂O₃, Al₂O₃) obeyed the Cassie theory. In the experiment using iron with 370?ppm Al, all the contact angles were higher than that using low Al-containing iron. The surface of the iron drop was covered with an oxide layer, which mainly consisted of many small particles. With the variation of the substrate gradually from MgO to Al₂O₃, the composition of the oxide layer changed from MgO·Al₂O₃ to CaOAl₂O₃. The formation of the oxide layer prevented the spreading of liquid iron, leading to the increase of the contact angle.