Theoretical Investigation on Photoionization and Dissociative Photoionization of Toluene

The photoionization and dissociation photoionization of toluene have been studied using quantum chemistry methods.The geometries and frequencies of the reactants,transition states and products have been performed at B3LYP/6-311++G (d,p) level,and single-point energy calculations for all the stationary points were carried out at DFT calculations of the optimized structures with the G3B3 level.The ionization energies of toluene and the appearance energies for major fragment ions,C₇H₇⁺,C₆H₅⁺,C₅H₆⁺,C₅H₅⁺,are determined to be 8.90,11.15 or 11.03,12.72,13.69,16.28 eV,respectively,which are all in good agreement with published experimental data.With the help of available published experimental data and theoretical results,four dissociative photoionization channels have been proposed:C₇H₇⁺+H,C₆H₅⁺+CH₃,C₅H₆⁺+C₂H₂,C₅H₅⁺+C₂H₂+H.Transition structures and intermediates for those isomerization processes are determined in this work.Especially,the structures of C₅H₆⁺ and C₅H₅⁺ produced by dissociative photoionization of toluene have been defined as chain structure in this work with theoretical calculations.     

凹凸棒石负载Cu-Fe-Co基催化剂组合体系用于CO加氢制备低碳醇

采用浸渍法(IM)和浸渍燃烧法(IMSC)制备了凹凸棒石(ATP)及凹凸棒石-多孔硅胶微球混合物(ATPS)负载CuFe-Co基改性费托催化剂,通过N_2吸附-脱附、X射线衍射(XRD)、X射线光电子能谱(XPS)、扫描电镜(SEM)、透射电镜(TEM)、H_2-程序升温还原(H_2-TPR)和CO_2-程序升温脱附(CO_2-TPD)等手段对催化剂进行了表征,并将它们应用于CO加氢制备低碳醇反应。结果表明,IMSC较IM制备催化剂更有利于CuO的负载、分散和还原,促进H_2和CO与Cu活性位的接触,但两者的最佳低碳醇合成温度均为280℃。通过对ATP和ATPS负载Cu-Fe-Co基催化剂(CFCK/ATP、CFCK/ATPS)与Cu/ZnO/Al_2O_3(CZA)甲醇催化剂的组合体系的优化,获得较理想的低碳醇合成催化剂组合体系CZA║CFCK/ATPS-IMSC。利用它们之间的"产物转化耦合效应",实现CO转化率为46.3%,低碳醇选择性为39.6%,C_(2+)醇含量为22.7%。     

An Intrinsic Photothermal Liquid for Light Detection and Energy Storage

Photothermal materials (PTMs) have been intensively investigated in the fields of photothermal conversion. Superior to solid PTMs, liquid PTMs are leading the trends in satisfying the demands of high flexibility and easy recycling. Successful examples of liquid PTMs are mostly formulated by dispersing solid PTMs in solvents, but suffer from the problems of phase segregation and solvent pollution. In this work, a low-cost formulation is proposed, which involves an oxidative product of ethyl oleate by iodine. It is an intrinsic liquid PTM, preserving the fluidic nature as well as possessing considerable ability for photothermal conversion. In addition to understanding the mechanism of light absorption in the visible and even near infrared windows, two examples are presented to demonstrate the great potential of liquid PTMs in broad areas such as light sensing and energy storage.     

高效液相色谱-质谱法分析测定水中氨基甲酸酯

采用固相萃取-高效液相色谱-质谱法（LC／MS）检测研究了水中氨基甲酸酯农药残留。水样用固相萃取富集净化,环己烷＋乙酸乙酯（1＋1）洗脱;以甲醇-10mmol／L乙酸铵为梯度流动相,Symmetry C18柱高效液相色谱分离。电喷雾正离子模式,选择质子化氨基甲酸酯分子离子[M＋H]^＋为定量离子进行MS测定。结果表明,6种氨基甲酸酯组分的平均加标回收率为73．5％～89．8％;相对标准偏差为4．50％～12．6％;水样浓缩至1／2500后的检出限为0．8～3．2ng／L。本法具有非常高的选择性、灵敏度和准确度,完全能满足水中痕量氨基甲酸酯农残的高灵敏分析。     

高度分散的Pt/TiO2的制备及光催化活性

用柠檬酸作为空穴捕获剂和分散剂,在温和条件下用光催化还原法将3nm金属铂沉积在7nm的锐钛矿相及介孔二氧化钛纳米晶表面,TEM观察显示铂的负载量为w=1．0％时,多数二氧化钛纳米晶表面沉积了岛状的铂团簇,XPS和电子衍射结果表明铂以游离态存在．负载w=1．0％～2．0％铂的TiO2在苯酚光氧化反应中活性显著提高,Pt/TiO2在氨气中经550℃氮化,可制得氮掺杂的Pt／TiO2可见光光催化剂,氮化过程中铂团簇没有烧结和显著长大。     

Synthesis of Asymmetric 4H-1, 3, 2-Benzodioxaphosphorin 2-Sulfides from Intramolecular Cyclization Reaction

Avarietyofbiologicalactivitiesofsome4H-l,3,2-benzodioxaphosphorin2-sulfideshavebeenreported,forexampletheinsecticideSalithionl.Thecyclicphosphonothionateshavebeenpreparedbyintermolecularcondensationofphosphorodichloridothioateswithsalicylalcoholoritsderivativesinthepresenceofabase=,andbyintramolecularcyclizationreactionofthesalicylalasthestartingmaterial3.However,theintramolecularcyclizationreactionofthe2-hydrobenzophenonesandstereochemicalstudieshavenotbeenreported.Wenowdescribeanewsynthesis…     

一步法合成取代-1,2-苯醌类化合物

应用固定化多酚氧化酶催化的氧化-迈克尔加成反应,一步合成了4,5-二取代-1,2-苯醌类化合物:4,5-N,N-二(苯胺基)-1,2-苯醌,4,5-N,N-二(对甲苯胺基)-1,2-苯醌,4,5-N,N-二(间氯苯胺基)-1,2-苯醌,4,5-N,N-二(对溴苯胺基)-1,2-苯醌。用化学法(I_2—KI)进行氧化-迈克尔加成反应也成功地合成了4,5-二取代-1,2-苯醌类化合物。应用紫外光谱方法证明了氧化-迈克尔加成反应的机制。     

酰胺型双冠醚的振动光谱分析

对邻苯-二(氧乙酰胺-4'-本并-15-冠-5)、间苯-二(氧乙酰胺-4'-苯并-15-冠-5)、对苯-二(氧乙酰胶-4'-苯并-15-冠-5)三种酰胺型双冠醚和苯并15-冠-5的喇曼光谱及红外光谱进行了测定和归属分析,并与15-冠-5的喇曼及红外光谱进行了比较研究.     

Design and synthesis of interpenetrating polymer networks for second-order nonlinear optics

There has been a tremendous recent interest in the development of second-order nonlinear optical (NLO) polymeric materials for photonic applications. However, a major drawback of second-order NLO polymers that prevents them from being used in device applications is the instability of their electric field induced dipolar alignment. The randomization of the dipole orientation leads to the decay of second-order optical nonlinearities. Numerous efforts have been made to increase the stability of the second-order NLO properties of polymers. The search for new approaches to develop NLO polymers with optimal properties has been an active research area since the past decade. A novel approach, combining the hybrid properties of high glass transition temperatures, extensively extensively crosslinked networks and permanent entanglements, based on interpenetrating polymer networks (IPN) is introduced to develop stable second-order NLO materials. Two types of IPN systems are prepared and their properties are investigated. The designing criteria and the rationale for the selection of polymers are discussed. The IPN samples show excellent temporal stability at elevated temperatures. Long-term stability of the optical nonlinearity at 100°C has been observed in these materials. Temporal stability of the NLO properties of these IPNs is synergistically enhanced. Relaxation behavior of the optical nonlinearity of an IPN system has been studied and compared with that of a typical guest/host system. The improved temporal stability of the second-order NLO properties of this IPN system is a result of the combination of the high rigidity of the polymer backbones, crosslinked matrices and permanent entanglements of the polymer networks. A slight modification of the chemical structure resulted in an improvement of the optical quality of the sample.     

气相色谱法测定榄香烯含量

以正己醇为内标,用气相色谱法测定榄香烯及其制剂,方法简便、快速,结果准确,可作为控制质量的方法。