Deuterium Inverse Isotopic Effect in Hydrogenation of Nitrogen into Ammonia

氨合成催化反应实现工业化已经有近百年历史，它不仅解决了人口急剧增加带来的粮食危机问题，而且奠定了多相催化科学研究的基础，带动了一系列的基础理论研究。然而，尽管在这样一个比较简单的体系上已经进行了大量研究工作，但迄今还不能说对这一催化反应体系已在分子水平上达到透彻的了解，仍有一些问题未获解决，如在氢是否参与氮分子解离的氨合成反应速率控制步骤的问题上还有不同的看法。 本文从氨合成反应的氘同位素效应、与N2等电子数，结构上相似的CO加氢甲烷化反应的氘同位素效应，以及碱土金属化合物促进剂促进机理等三个方面开展研究，以期为氢是否参与N2吸附解离的氨合成反应速率控制步骤的分歧提供有意义的信息。 本文第...The industrialization of ammonia synthesis has not only solved the food crisis problem caused by the rapid increasing of population, but also established the basis of heterogeneous catalysis and drove a series of fundamental research. Extensive and intensive researches have carried on this quite simple reaction. However, the thorough understanding into this catalytic reaction has not been achieved...学位：理学博士院系专业：化学化工学院化学系_物理化学(含化学物理)学号：B20032501

旋光度法测定蔗糖转化反应速率常数实验用旋光管的改进

用旋光度法测定蔗糖转化反应速率常数是最基本的物理化学实验之一。该实验中的旋光管操作比较麻烦,且易引入实验误差。本文对该实验使用的旋光管进行了改进

Improvement on Liquid Saturated Vapor Pressure Measurement

针对目前静态法测定液体饱和蒸汽压实验中饱和蒸汽压数值读取不合理,汽液两相未充分平衡等问题,改变传统的调整u型管两端液面等高后再读取数字压力计的方法。改进后的实验装置只需在u型管的两侧标上刻度,待系统恒温、汽-液充分平衡后,读取数字压力计的数值、温度以及u型管两端液面的高度差就可得到该温度下的液体饱和蒸汽压。该方法可解决静态法测定液体饱和蒸汽压实验中调整u型管两端液面等高耗时,空气容易倒灌的问题。This paper presented a method to improve the unreasonable design of liquid saturated vapor pressure measurement obtained by static method.The improvement changed the traditional method for measuring the liquid saturated vapor pressure which cannot get the pressure data until both sides of the U-type tube reach the same heigh of liquid level.After marking graduated lines on the two sides of the U-type tube,the liquid saturated vapor pressure can be easily obtained from digital pressure gauge,after the temperature becomes constant and the difference in the height of liquid level is balanced.The time-consuming problem of adjustment of liquid level height on both sides of the U-type tube and the problem of air flow backward could be solved perfectly.It is very helpful to enhance student's understanding of the concept of vapor-liquid equilibrium.国家基础科学人才培养基金项目(J1030415

Study on the performances of primary alkaline Zn-NiOOH/MnO_2 battery

[中文文摘]研制了以NiOOH与MnO2混合作正极活性物质、锌为负极的新一代实用碱性一次电池,弥补了目前广泛使用的碱锰电池大负荷放电性能不佳的缺陷。这种碱性Zn-NiOOH/MnO2电池1000mA大负荷放电至1.2V高压段的容量比碱锰电池提高了3.6倍,71!高温储存7d后,再放电至1.2V时容量保持率可达到73.8%,在室内储存1a后1000mA放电至1.2V的容量保持率还可达到85.6%。对这一新型电池在不同负荷下的放电容量和储存性能也进行了研究。[英文文摘]A new primary alkaline battery composing of NiOOH / MnO2 cathode and zinc anode was developed. This new type battery improved the performances of conventional primary alkaline Zn-MnO2 battery, which has not good heavy load discharge characteristic. The fresh capacity of primary alkaline Zn-NiOOH / MnO2 battery discharge at constant 1 000 mA to 1.2 V is 3.6 times higher than that of primary alkaline Zn-MnO2 battery. The capacity remain of Zn-NiOOH / MnO2 battery after storage at 71℃ for 7 d is 73.8%, and capacity remain after storage atroom for 1 year is 85.6%.Also,the discharge and storage perform ances of prim ary Zn-NiooH/Mno2 battery at different loads were studied

Preparation of Cu/Sr_3Ti_2O_7 and Its Photocatalytic Activity of Water-splitting for Hydrogen Evolution

[中文文摘]采用聚合合成法(PCM)合成出层状钙钛矿结构的Sr_3Ti_2O_7,进而负载Cu离子,制成Cu/Sr_3Ti_2O_7催化剂.以超纯水和甲醇牺牲剂体系的光催化分解反应为探针,通过检测氢气生成速率评价了催化剂的光催化性能,并借助光电子能谱(XPS)、X射线衍射(XRD)分析、紫外-可见漫反射光谱(UV-VisDRS)等手段对催化剂进行了表征.实验结果表明,Cu在催化剂中以多价态存在,Cu+和吸附氧有利于光生电子的转移.Cu/Sr_3Ti_2O_7催化剂较之纯Sr_3Ti_2O_7催化剂活性大大提高,Cu最佳负载量为1.5%(w).产氢速率可稳定在550-600μmol·h~(-1).还原过的Cu/Sr_3Ti_2O_7催化剂产氢速率最高可达1140.8μmol·h~(-1).[英文文摘]Sr_3Ti_2O_7 photocatalyst with perovskite-layered structure was synthesized by polymerized complex method (PCM). Cu ion as an effective dopant was loaded onto Sr_3Ti_2O_7 catalyst. Cu/Sr_3Ti_2O_7 catalyst was applied in the mixture of water and methanol, methanol was used as a sacrificial agent under ultra-violet irradiation, and the catalyst was characterized by XPS, XRD, and UV-Vis DRS. The results showed that Cu existed in several kinds of valence and the photocatalytic activity of Cu/Sr_3Ti_2O_7 was superior to that of pure Sr3Ti2O7. Cu+ and adsorbed oxygen can accelerate the interfacial electron transfer. When the amount of Cu was 1.5%(w), the best catalytic effect was obtained and the stable average hydrogen evolution rate was about 550- 600 μmol·h- 1. The Cu/Sr3Ti2O7 after reduction attained the highest hydrogen evolution rate that was close to 1140.8 μmol·h- 1.国家自然科学基金(20673089,20273053,20023001, 29933040); 973项目(001CB108906); 福建省科技重大专项(2005HZ01-3)资助

Effects of Fluoride on Activities of Ru-based Ammonia Synthesis Catalysts

[中文文摘]以MgO为载体 ,分别用KF ,KNO3 ,BaF2 和BaO为促进剂前驱体制备钌基氨合成催化剂 ,并用X射线衍射 (XRD)、高分辨透射电子显微镜 (HRTEM)和催化剂性能评价等方法考察了不同促进剂前驱体对钌基氨合成催化剂的影响 .结果表明 ,电负性比氯大的氟的引入能提高催化剂的活性 ,在KF Ru/MgO催化剂中 ,F与载体的O发生交换 ,改变了载体的结构和表面性质 ,从而导致金属载体相互作用情况的不同以及金属分散度的提高 ,因而有利于催化活性的提高 .同时 ,当F以BaF2的形态存在时也能提高催化活性。[英文文摘]A series of Ru based ammonia synthesis catalysts supported by magnesia with different promoter precursors were prepared. The effects of different promoter precursors on the catalysts were investigated by XRD, HRTEM and performance evaluation techniques. The results indicated that the activities of catalysts were increased by the introduction of fluoride and some oxygen of magnesia was exchanged with fluoride in KF-Ru/MgO catalyst. It was suggested that the exchange of oxygen and fluoride changed the structure and surface property of support , hence improving the metal dispersion and the different interactions of ruthenium and the support . Consequently , the activity of catalyst prepared with KF was higher. At the same time , the activity of catalyst prepared by BaF2 was also higher than the one prepared by BaO, though the configuration of fluoride and barium was BaF2.国家自然科学基金(Nos.20273053,20023001,299330 40); 国家重点基础研究发展规划(No.001CB108906)资助项目

Electronic States and Spectroscopic Properties of RuH_2 and RuN_2

[中文文摘]用量子化学从头算方法在B3LYP/6 311G 的水平上 ,研究了RuH2 和RuN2 可能的电子组态和光谱性质 .结果表明 ,RuH2 的3 B2 和5Σ-态对应于静电作用的物理吸附态 .RuN2 的一重态和三重态的计算结果跟钌单晶面上的实验值相接近 .而RuN2 在C∞v对称性时 ,五重态5Σ-的计算频率比实验值稍低 .在C2v对称性时 ,五重态的计算频率值则更低 ,3 B2 和5A1态不能稳定存在.[英文文摘]Using DFT method at B3LYP/6-311G ** level, the possible electronic states of RuH 2 and RuN 2 have been calculated, including the chemical adsorption and physical adsorption. For the RuH 2 cluster, electronic states 3B 2 and 5Σ - correspond to the physical adsorption. The RuN 2 calculation results were also compared with the experimental values on ruthenium single crystal surfaces. It is found that the single states and the triplet states are in good agreement with the experimental values. For the C∞v symmet ry , the calculated frequency of the quintuple state 5Σ- is slightly lower than the experimental value. For the C2v symmet ry , the f requencies of the quintuple states are much lower than the experiment value and the 3B2 and 5A1 states are unstable.Project supported by the the NSF of China (20273053,29933040 and 20023001)andthe 973 project of the DST of China(001CB108906)

Export System of Molecular Design for Metal Catalysts

用VisualBasic 5 0结构化语言实现了气 -固界面多相催化反应中金属催化剂分子设计的专家系统。知识库采用了Access型动态数据库 ,支持多用户和数据的即时更新。链接了可视化数据管理器VisData ,为知识库提供了添加、修改和查询等强大功能。推理机采用精确计算与模糊选择相结合的方法来确定一个反应所需要的催化剂。利用了面向对象的Windows编程方式 ,窗口界面非常友好直观和易于使用。而且 ,系统安装后 ,可脱离Vi sualBasic 5 0独立运行。The expert system for molecular design of metal catalysts in the heterogeneous catalytic reactions on gas solid interfaces was programmed using Visual Basic 5 0 structural language. An Access type dynamic database was employed in the knowledge base, which supported multi user and the instant update of data. The VisData was linked which provided strong function, such as appending, modification and search etc, to the knowledge base. To determinate a desire catalyst for a catalytic reaction, accurate computation combining with fuzzy selection was adopted in the inference engine. The window interfaces are very friendly and easy using since a windows type OOD programming method was used. Moreover, after success set up, the expert system can divorced from Visual Basic 5 0 and independently run.国家自然科学基金!资助项目 (编号 :2 97730 37

Green interfacial synthesis of two-dimensional poly(2,5-dimethoxyaniline) nanosheets as a promising electrode for high performance electrochemical capacitors

National Natural Science Foundation of China [51202004]; Natural Science Foundation of Anhui Province [KJ2013A051]; CAS Key Laboratory of Materials for Energy Conversion [2014001]2D poly(2,5-dimethoxyaniline) nanosheets were first designed and tailored as intriguing pseudo-capacitive electrode for advanced supercapacitors via green interfacial synthetic strategy, and yielded large specific capacitance (SC) and remarkable SC retention at high rates in 1 M HCl electrolyte

Deuterium Inverse Isotopic Effect in Ammonia Synthesis over Ru-Based and Fe-Based Catalysts

联系人: 林敬东.Tel:(0592)2183045;Fax:(0592)2183043; E-mail: [email protected] 廖代伟. Tel:(0592)2183045;Fax:(0592)2183043; E-mail: [email protected][中文文摘]氘反同位素效应是合理阐明过渡金属催化剂上氨合成催化反应机理的重要实验依据之一.在N2/H2(或D2)体积比1/3,0.2MPa,633～733K和GHSV=24000或12000h-1的条件下,检测到了Ru基(纯Ru,Ru/γ-Al2O3,K-Ru/γ-Al2O3,Ru/MgO,K-Ru/MgO和Ba-Ru/MgO)和Fe基(纯Fe和A110-3)催化剂上强的氘反同位素效应(rD/rH≈2),其数值随催化剂和反应温度的变化而变化.这可能是动力学同位素效应与热力学同位素效应二者相互强竞争的结果.[英文文摘]The deuterium inverse isotopic effect (DIIE) is important for the clarification of the ammonia synthesis mechanism over transition metal catalysts. We investigated the DIIE over Ru-based and Fe-based catalysts including pure Fe,multi-promoted fused Fe,pure Ru,Ru/γ-Al2O3,K-Ru/γ-Al2O3,Ru/MgO,K-Ru/MgO,and Ba-Ru/MgO under the reaction conditions of N2/H2 (or D2) volume ratio = 1/3,0.2 MPa,633–733 K,and GHSV = 24 000 and 12 000 h?1. A strong DIIE (rD/rH of about 2) was observed over the above catalysts. The trend of the DIIE with catalysts and temperature indicated a strong competition between the dynamic and thermodynamic factors.国家自然科学基金(20673089);国家重点基础研究发展计划(973计划,2009CB939804