垃圾焚烧炉渣粉替代矿粉对沥青混合料性能的影响

探讨了生活垃圾焚烧(MSWI)炉渣粉料(BAP)100%(质量分数)替代矿粉配制沥青混合料的可行性及其对沥青混合料性能的影响.进行了炉渣粉沥青混合料的配合比设计,分析了炉渣粉料对各项马歇尔指标以及沥青用量的影响;评价了炉渣粉料对沥青混合料路用性能的影响.结果表明:炉渣粉料的加入会使设计沥青用量增加,沥青混合料的马歇尔稳定度有所提高;炉渣粉料的表面形貌粗糙多孔,提高了沥青混合料的高温稳定性;炉渣粉料替代矿粉后,设计沥青用量的增加和混合料内部嵌挤结构的增强可以改善沥青混合料的低温抗裂性能;炉渣粉料中的Si O2和金属氧化物会导致沥青混合料的水稳定性有略微的降低;沥青对炉渣粉料的浸润更加良好,黏附状况更加理想.     

Bulk Al–Al3Zr composite prepared by mechanical alloying and hot extrusion for high-temperature applications

Bulk Al/Al3Zr composite was prepared by a combination of mechanical alloying (MA) and hot extrusion processes. Elemental Al and Zr powders were milled for up to 10 h and heat treated at 600°C for 1 h to form stable Al3Zr. The prepared Al3Zr powder was then mixed with the pure Al powder to produce an Al–Al3Zr composite. The composite powder was finally consolidated by hot extrusion at 550°C. The mechanical properties of consolidated samples were evaluated by hardness and tension tests at room and elevated temperatures. The results show that annealing of the 10-h-milled powder at 600°C for 1 h led to the formation of a stable Al3Zr phase. Differential scanning calorime-try (DSC) results confirmed that the formation of Al3Zr began with the nucleation of a metastable phase, which subsequently transformed to the stable tetragonal Al3Zr structure. The tension yield strength of the Al?10wt%Al3Zr composite was determined to be 103 MPa, which is approximately twice that for pure Al (53 MPa). The yield stress of the Al/Al3Zr composite at 300°C is just 10% lower than that at room tem-perature, which demonstrates the strong potential for the prepared composite to be used in high-temperature structural applications.     

New-corrected functions of X-ray powder diffraction

X-ray powder diffraction is an indispensable technique to study material structure, phase transition and so on. It is necessary for high quality diffraction data to get high-precision diffraction angle. This work proposed four corrected functions of X-ray powder diffraction angle. Two methods, linearization method and modified Levenberg-Marquardt iteration method, are given to solve the function parameters, and the modified Levenberg-Marquardt method has fast convergent speed and stable solution. Two methods can give closed parameters, including those of Lu, Liu, and Chu functions and polynomial. New-corrected functions were used to fit the diffraction angle error of the tetragonal rutile polycrystalline TiO2 mixed with Gd0.45Y2.55Sc2Ga3O12 as a standard sample, and the computation result indicates that these functions can characterize the diffraction error very well. In some cases, the new-corrected functions can describe the diffraction angle error better than the reported corrected functions. At the same time, the lattice parameter of Gdo.45Y2.55Sc2Ga3O12 was computed with two methods. When the corrected function parameters and lattice parameters were solved by the least square method, the interaction of the function parameters and lattice parameters would result in great error. However, when the X-ray diffraction angles were corrected by corrected functions using a standard sample, the authentic lattice parameters can be obtained by the least square fitting.     

低品位硼铁矿中硼的富集

采用还原焙烧、磁选工艺流程和粉矿直接入炉焙烧技术,对难选低品位硼铁矿中硼的富集进行了研究.按化学当量比C/O=1(原子比)进行配碳,使用马弗炉进行焙烧实验,在500～1 450℃研究了不同焙烧温度下硼品位和硼回收率的变化.研究结果表明:随着焙烧温度的提高,铁晶颗粒增大,在1 200℃时硼精粉品位达到14.29%,满足硼化工工业对硼品位的要求(ω(B2O3)≥12%);硼回收率在1 200℃以上时能达到90%以上.当焙烧温度在1 350℃以上时,硼的回收率和品位没有太大的变化.焙烧温度选择在1 200～1 350℃为宜,既能实现高的硼回收率,硼品位又能满足硼化工工业的要求.     

赤灵芝及其孢子粉提取物缓解小鼠肝脏CCl4损伤的研究

用赤灵芝及其孢子粉混合提取后的流浸膏,以一定剂量每日灌胃处理组小鼠,用蒸馏水灌胃空白组和模型组,29天后,一次性给予除空白组外的各组小鼠一定剂量的CCl4,24 h后测定血清中ALT和AST的含量,同时取左侧肝脏进行组织病理学检查.结果显示:模型组小鼠的ALT、AST含量比空白组显著升高,低、中、高剂量组小鼠的ALT和AST含量较模型组低,差异显著或极显著.与模型组比较,各剂量组小鼠肝细胞损伤的各种病变有所减轻,气球变性、肝细胞坏死和总分等三项指标差异有统计学意义.表明赤灵芝及其孢子粉的提取物对小鼠CCl4肝损伤具有缓解的作用.     

液相色谱质谱联用法快速测定配方奶粉中的三聚氰胺

应用液相色谱质谱联用法测定配方奶粉样品中的三聚氰胺.试样用三氯乙酸溶液提取,经阳离子交换固相萃取柱净化后,用液相色谱质谱法测定和确证,外标法定量.采用电喷雾离子源,定性离子对为127/85和127/68;定量离子对为127/85.样品的三聚氰胺标准加入回收率为91.6%～104.2%;相对标准偏差(RSD)1.2%～2.6%;检出限为0.2 mg/kg.     

粉体喷射搅拌桩施工方法

作为处理软土地基手段之一的深层粉体搅拌桩,在我国土建工程中,已得到广泛使用.其结构型式,可分为块式、壁式、格子式和桩式4种.在公路工程中,采用柱式为主适用于加固淤泥、淤泥质土、黏土、粉土等软弱地层,尤其是高路堤和桥头接坡等.     

三元共聚物对纳米Si_3N_4粉体表面改性的研究

采用自制的三元共聚物BA-MMA-GMA作为大分子改性剂对纳米Si3N4粉体进行表面包覆处理,利用红外、热重分析、粒径分布、接触角、透射电镜分析等手段进行表征.结果表明:三元共聚物与纳米粉体间既存在化学键合,也存在物理包覆,可以有效阻止纳米Si3N4粉体的团聚.改性后的纳米粉体表面自由能显著降低,在有机溶剂中的分散稳定性显著增加.     

绿色环保型无磷洗衣粉配方的研制

以烷基糖苷为主表面活性剂,复配其他活性成份,研制出一种新型绿色环保无磷洗衣粉。通过正交试验优化组合,得到一个以烷基糖苷、甜菜碱和过碳酸钠为替代磷助剂的无磷洗衣粉配方。将该配方与几种市售洗衣粉进行了去污力等性能的对比。结果表明,该配方绿色环保,具有良好地去污性。     

Reduction of 1-3 mm iron ore by H2 in a fluidized bed

The reduction of 1-3 mm fine powder of iron ore by H₂ was conducted in a lab-fabricated kg class high temperature fluidized bed. The results show that the differential pressure in the fluidized bed, which has small fluctuation with time, increases with the increase of gas flowing velocity. The utilization ratio of gas decreases when the reaction lasts longer time indicating that the reaction is faster at the beginning of reduction and becomes slower in the latter process. The higher the reaction temperature is, the higher the utilization ratio of gas is, but the difference of utilization ratio among the different temperatures becomes smaller with time. The utilization ratio of gas and the metallization ratio can reach 9% and 84% respectively at 750℃ for 20 min, which shows the reduction reaction by H₂ is very fast. The increase of metallization ratio with gas velocity performs quite good linearity, which shows that a higher velocity of reducing gas can be used to improve the productivity of the reactor when H₂ is used as reducing gas. With the increase of charge height, the metallization ratio decreases, but the utilization ratio of gas increases. The reaction temperature can be reduced to 700-750℃ from 800-850℃ when H₂ is used as reducing gas.