Catalytic behavior in CH4 decomposition of catalysts derived from red mud: Impact of residual Na2O

Catalyst samples for CH₄ decomposition were prepared from red mud (RM) by an acid-leaching neutralization precipitation approach. Water-washing the resultant precipitates multiple times, followed by drying at 105 °C and calcination at 500 °C, resulted in a threshold of residual Na₂O, equivalent to 96% Na₂O removal. Drying the precipitate at a higher temperature of 200 °C, followed by repeated water washing, provided a deeper Na₂O removal of 99% and made the resultant samples more active for the targeted reaction. Subsequently, four catalyst samples with a simulated red mud composition and NaOH contents from 0 to 0.3 wt% were prepared and the catalytic test results revealed that the Na₂O remaining in the RM-derived catalysts did not only inhibit their activation in CH₄ but also lower their maximal activities for CH₄ decomposition. Finally, two catalysts with the same simulated red mud composition and their Na impregnated respectively on Fe₂O₃ and a mixture support of Al₂O₃-SiO₂-TiO₂ were prepared and tested to explore the effect of Na distribution on the activation behavior of RM-derived catalysts for CH₄ decomposition. The activity testing results showed that it was the Na residual dispersed on iron oxides in the RM-derived samples to significantly inhibit the activation of CH₄ decomposition.     

Hydrogen Production from Catalytic Steam Reforming of Bio-Oils: A Critical Review

In the future, hydrogen will be an important energy carrier and industrial raw material. Catalytic steam reforming of bio-oils is a promising and economically viable technology for hydrogen production. However, during the reforming process, the catalysts are rapidly deactivated due to coke formation and sintering. Thus, maintaining the activity and stability of catalysts is the key issue in this process. Optimized operation conditions could extend the catalyst lifetime by affecting the coke morphology or promoting coke gasification. This article summarizes the recent developments in the field of catalytic steam reforming of bio-oils, focusing on the operation conditions, the properties of the catalysts, and the effects of the catalyst supports. The expected insights into the catalytic steam reforming of bio-oils will provide further guidance for hydrogen production from bio-oils.     

油页岩矿物质催化半焦燃烧特性及机理

利用微型流化床反应分析仪（MFBRA）研究了油页岩矿物质催化半焦燃烧特性，重点考察了半焦内部矿物质和外部页岩灰床料对半焦燃烧的催化作用，揭示了流化床反应器中半焦燃烧过程和机理。结果表明：内部矿物质和外部床料对半焦燃烧均具有明显催化作用，而两者共同催化效果最为显著。矿物质中CaO和Fe₂O₃对半焦燃烧具有催化活性，CaO催化作用强于Fe₂O₃。油页岩半焦燃烧反应活化能在60.41~78.97 kJ/mol之间，矿物质的催化作用会明显降低反应活化能。流化床反应器中，矿物质对半焦燃烧的催化作用主要表现在四个反应，即：挥发分裂解和燃烧、半焦表面炭燃烧、半焦内部炭燃烧以及一氧化碳燃烧。     

自保护药芯焊丝明弧堆焊Fe-Cr-C-B-W合金的组织及性能

采用自保护药芯焊丝明弧堆焊技术制备五组不同钨含量的Fe-Cr-C-B-W合金. 借助金相显微镜、扫描电子显微镜、X射线衍射仪、洛氏硬度计和磨损试验机分析堆焊合金的组织及性能. 结果表明，合金的显微组织由马氏体、残余奥氏体、M₇(C,B)₃，M₃(C,B)，Fe₃W₃C和WC组成. 大部分钨元素被迁移到晶界生成了比WC稳定性更好的Fe₃W₃C缺碳复合相，堆焊层中没有典型的初生WC硬质相颗粒生成. 随着钨添加量的增多，共晶硬质相M₇(C,B)₃，M₃(C,B)和Fe₃W₃C随之增多，间距减小，呈连续网状均匀分布. 当钨的添加量为12%时，堆焊层的耐磨性达到最佳.     

SO4^2-／ZrO2固体超强酸的制备及其催化合成ETBE的研究

采用沉淀一浸渍法制备了负载型SO4^2-／ZrO2固体超强酸催化剂，运用IR、XRD等方法表征所制备催化剂的物化性质。结果表明，所制备的催化剂具有固体超强酸催化剂的特征，酸性与焙烧温度有关，适当提高焙烧温度有利于样品酸强度的提高，但焙烧温度过高会导致脱硫；浸渍液H2SO4浓度高有利于提高催化剂的硫含量，但是浓度过高，会在催化剂上形成硫酸盐，从而降低催化剂的比表面积和酸性。采用制备的催化剂气相催化乙醇与叔丁醇合成乙基叔丁基醚反应，乙基叔丁基醚的选择性为54．71％。     

石化企业线性规划模型的自动生成

根据石化企业生产过程的实际情况，考虑原料供应量、装置加工能力、物料平衡和价格等情况．建芷反映企业生产情况的线性规划数学模型。分别阐述了模型的决策变量、目标函数和约束方程的自动生成的方法，并给出了模型文件的存储结构。     

Using direct competition to select for competent controllers in evolutionary robotics

Evolutionary robotics (ER) is a field of research that applies artificial evolution toward the automatic design and synthesis of intelligent robot controllers. The preceding decade saw numerous advances in evolutionary robotics hardware and software systems. However, the sophistication of resulting robot controllers has remained nearly static over this period of time. Here, we make the case that current methods of controller fitness evaluation are primary factors limiting the further development of ER. To address this, we define a form of fitness evaluation that relies on intra-population competition. In this research, complex neural networks were trained to control robots playing a competitive team game. To limit the amount of human bias or know-how injected into the evolving controllers, selection was based on whether controllers won or lost games. The robots relied on video sensing of their environment, and the neural networks required on the order of 150 inputs. This represents an order of magnitude increase in sensor complexity compared to other research in this field. Evolved controllers were tested extensively in real fully-autonomous robots and in simulation. Results and experiments are presented to characterize the training process and the acquisition of controller competency under different evolutionary conditions.     

咪唑啉缓蚀剂工艺条件优化及效果

在减缓金属腐蚀的研究中,为了缓解在酸性溶液、碱性溶液以及大气、土壤等介质中金属腐蚀较为严重的问题,对咪唑啉类缓蚀剂进行了工艺条件优化.采用静态失重法研究了碳钢在加入了缓蚀剂的盐酸溶液中的缓蚀性能.在最佳合成条件下苯甲酸与二乙烯三胺最佳摩尔比为1∶1.3,催化剂质量分数为1.2%,环化时间为1 h,咪唑啉中间体与氯化苄的最佳摩尔比为1∶1.1,季铵化反应时间为1 h,季铵化反应温度为70 ℃,缓蚀剂的最佳质量分数为1%,最终缓蚀率可以达到99.37%.     

显微组织对Ni-Cr合金热腐蚀行为的影响

采用机械合金化法和真空熔炼法制备了不同显微组织的Ni-20Cr（质量分数，％，下同）合金，并研究其在950℃，75％Na2SO4＋25％K2SO4（质量分数，下同）盐膜下的热腐蚀行为。结果表明：细晶的机械合金化Ni-20Cr合金热腐蚀后表面形成了单一连续的Cr2O3外氧化膜，有效地阻止了硫的向内扩散，延长了热腐蚀过程的孕育期，呈现出较普通晶粒尺寸的熔炼Ni-20Cr合金更好的抗热腐蚀性能。