范例一(煤炭学报,2004.3.):
超细煤粉颗粒形状分形维数与球磨工艺的研究
杨志远,曲建林,周安宁
(西安科技大学材料科学与工程系,陕西西安 710054)
摘 要:在行星磨完成不同煤的超细粉碎.基于面积-周长法,利用煤粉颗粒的SEM图像结合图像分析软件计算不同工艺条件下的煤粉体的颗粒形状分形维数,结果表明:该方法计算的分维值相关系数多在0.95以上;煤颗粒形状分形是多域度分形;煤颗粒粉碎初期形状分形维数逐渐减小,当粉碎到团聚时间时,其分形维数值反而在增大;含碳量高的煤质在粉碎时,其形状分形维数一般较小;不同助磨剂对颗粒形状分形的影响不同.
关键词:超细煤粉;颗粒形状分形;球磨工艺;行星磨
Study on the relationships between the profile fractal dimensions of coal ultra-fine powders and their grinding technologies
YANG Zhi-yuan, QUJian-lin, ZHOUAn-ning
(Dept.of Material Science and Engineering, Xi’an University of Science and Technology, Xi’an710054,China)
Abstract:The different coals were pulverized into ultra-fine powders on a planetary mill. On the basis of SEM photographs and image analysis software, the profile fractal dimensions of coal ultra-fine particles were calculated by using the Area-Perimeter Method, which produced in different grinding technologies. The results indicated that the Area-Perimeter Method can apply in calculation of the fractal dimensions with its correlated coefficient over 0.95;the profiles of coal particles are multifractals; in the initial period the fractal dimensions decrease with the time whereas the fractal dimensions of coal agglomerates increase with the time; ingrinding, the profile fractal dimensions of coal particles with high carbon content, and different grinding assistant additives have different effects for the profile fractal dimensions.
Key words:ultra-fine coal powder; profile fractal dimension; grinding technologies; planetary mill
范例二(中国矿业大学学报,2008.04):
神府煤不同密度级组分光催化氧化的XPS研究
杨志远1,2,周安宁1,张 泓2,张 群2
(1.西安科技大学化学化工学院,陕西西安 710054;2.煤炭科学研究总院西安研究院,陕西西安 710054)
摘要:利用XPS对比分析神府脱灰煤及其两个密度级组分D3(1.375~1.400 g/cm3)和D4(>1.400 g/cm3)在低温光催化氧化前后表面化学键的变化,结果表明:煤表面主要含氧官能团以碳氧键(C-O)为主,氮的存在形式在D3组分中以吡咯型氮(N-5)和吡啶型(N-6)氮为主,D4组分中主要为吡咯型氮;神府脱灰煤主要是质子化吡啶型氮和吡咯型氮.光催化氧化50 h后,神府煤表面含氧官能团含量减小,碳碳骨架键(C-C)含量增大;煤中内部质子化吡啶(N-Q)转化为芳香环边缘上的吡啶氮或吡咯氮.
关键词:神府煤;不同密度级组分;光催化氧化;XPS
XPS Analysis of Shenfu Coal with Different Density Fraction Under UV Catalytic Photooxidation
YANG Zhi-yuan1,2,ZHOU An-ning2,ZHANG Hong2,ZHANG Qun2
(1.School of Chemistry & Chemical Engineering, Xi'an University of Science and Technology, X i'an,Shaanxi710054,China;2.Geology Institute, Xi'an Branch of China Coal Research Institute, Xi'an, Shaanxi 710054,China)
Abstract:The UV photooxidation of Shenfu coal with different density fraction, which named D3(1.375-1.400 g/cm3)and D4(>1.400 g/cm3), respectively, were carried out in a fixed bed photoreactor. The difference of structural characteristics on the surface of coal and its density fraction were analyzed comparatively using a X-ray photoelectron spectroscopy(XPS) method. The results show that the main form of oxygenous functional groups is C-O on the coal surface. Three types of coal nitrogen(pyrrolic, pyridinic and quaternary functionalities)in coal and its different density fraction, were found. The main forms of nitrogen on the surfaces of Shenfu coal were quaternary and pyrrolic, while on the surfaces of D3 density fraction were pyrrolic and pyridinic,D4 density fraction were pyrrolic, respectively. After the UV photooxidation of coal samples, the contents of oxygen functional groups of all coal samples decreased, while the contents of C-C increased. Meanwhile, the forms of quaternary nitrogen also converted to pyrrolic and pyridinic nitrogen on the surface of coal.
Key words:Shenfu coal; different density fraction; catalytic photooxidation; XPS