Chemische Ionisations-Massenspektrometrie von Organophosphors?ureinsecticiden mit verschiedenen Reaktantgasen

Zusammenfassung Chemische Ionisations-Massen-spektren (CI-MS) wurden mit einer Kopplung Dünnfilmcapillar-Gas-Chromatographie-Massenspektrometrie von 23 Organophosphorsäurepesticiden mit Isobutan als Reaktantgas gemessen. Alle Substanzen zeigten im CI-MS ein intensives Ion bei M + 1. Die CI-MS der einzelnen Substanzen werden diskutiert und mit Elektronenstoß-MS und CI-MS, die mit Methan oder Methanol als Reaktantgas erhalten wurden, verglichen. Die MS werden beim Übergang von Elektronenstoßionisation zu CI mit den Reaktantgasen Methan, Isobutan und Methanol in dieser Reihenfolge einfacher. Mit Methanol wird nur noch das M + 1-Ion gefunden. Für die praktische Rückstandsanalyse wird Isobutan als Reaktantgas vorgeschlagen.

---

Chemical ionization mass spectrometry of organophosphorus pesticides with various reagent gases

Summary Chemical ionization mass spectra (CI-MS) of 23 organophosphorus pesticides with isobutane as reagent gas were obtained by a combination of open tubular column gas chromatography-mass spectrometry. All substances show intense M + 1 ions in the CI-MS. The CI-MS of the individual substances obtained with isobutane were discussed and compared with their electron impact mass spectra (EI-MS) and CI-MS obtained with methane or methanol as reagent gases. The spectra became simpler applying CI-MS instead of EI-MS. In CI-MS the extent of fragmentation decreased changing the reagent gas from methane to isobutane and methanol. With methanol, usually only the M + 1 ion was observed in the spectra. For routine residue analysis, isobutane as reagent gas is recommended.

     

水热改性对NiMo/γ-Al2O3加氢脱氮催化剂结构及性能的影响

The influence of hydrothermal modification on the structure and hydrodenitrogenation (HDN) activity of NiMo/γ-Al₂O₃catalyst was studied in the range 140～180 ℃. The experimental results indicated that the hydrodenitrogenation reaction rate of pyridine was accelerated using the NiMo/γ-Al₂O₃catalyst synthesized via hydrothermal route due to the change of the structure, the increase of the amount of Mo and Ni and the rise of the specific surface area. The change of the structure of catalysts was enhanced at higher hydrothermal temperature, producing NiMo/γ-Al₂O₃catalyst with better HDN activity.     

含噁二唑单元共轭聚合物合成与性质研究

单体 2 ,5 双 (4 溴苯 ) 1,3,4 二唑 (M Ⅰ )与 1,4 二乙烯基 2 ,5 二正丁氧基苯 (M Ⅱ ) ,在钯催化下通过Heck偶合反应合成得到共轭聚合物 ;单体和聚合物进行了1 H NMR ,1 3C NMR、质谱、FT IR、UV、荧光光谱、GPC、元素分析、热分析等测试 ;二唑 (OXD)基团是一种很好的生色团 ,对氧和热特别稳定 ,二唑环的亲电子性能使其特别适合于作为电子传输层 ,聚合物能发射很强的绿色荧光 ,它将是一类潜在的光电高分子材料     

N-取代螺旋共轭化合物非线性光学性质的理论研究

以量子化学半经验AM1方法优化几何构型为基础，采用FF／AMl和INDO-SOS方法计算了N-取代螺旋共轭化合物的非线性光学系数，讨论了N原子不同取代位置对螺旋共轭体系结构、电子光谱、非线性光学系数的影响．计算结果表明，N杂原子的引入可改善体系的非线性光学性质，所设计的分子具有较大的二阶非线性光学系数和较好的透明性．     

金负载量对低温水煤气变换Au/α-Fe2O3催化剂结构和性能的影响

采用共沉淀法制备了低温水煤气变换Au/α-Fe2O3催化剂。通过正交实验优化催化剂的还原活化条件，考察了金负载量对催化剂性能的影响。采用BET、XRD、UV-VIS、XRF、H2-TPR和O2-TPO等表征手段对催化剂的结构进行分析，并与其催化性能进行关联。结果表明，（1）采用10%-H2/N2还原气将催化剂在150 ℃原位还原9 h，其催化活性最高；（2）金的最佳负载量为8.00%，此时在催化剂制备过程中金的流失量较少，金粒子较小，也有利于抑制催化剂在反应过程中烧结；（3）TPR-TPO结果表明，金的负载量为8.00%时，Au/α-Fe2O3催化剂具有较易被还原、不易被氧化的性质，从而显示出最高催化活性。（4）Au/α-Fe2O3催化剂中的金以单质金（Au0）形式存在；其高活性与Au0-Fe3O4间的协同作用有关。     

Structural investigation of high-valent manganese-salen complexes by UV/Vis,Raman, XANES,and EXAFS spectroscopy

XANES and EXAFS spectroscopic studies at the Mn-K- and Br-K-edge of reaction products of (S,S)-(+)-N,N'-bis(3,5-di-tert-butylsalicylidene)-1,2-cyclohexanediaminomanganese(III) chloride ([(salen)Mn(III)Cl], 1) and (S,S)-(+)-N,N'-bis(3,5-di-tert-butylsalicylidene)-1,2-cyclohexanediaminomanganese(III) bromide ([(salen)Mn(III)Br], 2) with 4-phenylpyridine N-oxide (4-PPNO) and 3-chloroperoxybenzoic acid (MCPBA) are reported. The reaction of the Mn(III) complexes with two equivalents of 4-PPNO leads to a hexacoordinated compound, in which the manganese atom is octahedrally coordinated by four oxygen/nitrogen atoms of the salen ligand at an average distance of approximately 1.90 A and two additional, axially bonded oxygen atoms of the 4-PPNO at 2.25 A. The oxidation state of this complex was determined as approximately +IV by a comparative study of Mn(III) and Mn(V) reference compounds. The green intermediate obtained in reactions of MCPBA and solutions of 1 or 2 in acetonitrile was investigated with XANES, EXAFS, UV/Vis, and Raman spectroscopy, and an increase of the coordination number of the manganese atoms from 4 to 5 and the complete abstraction of the halide was observed. A formal oxidation state of IV was deduced from the relative position of the pre-edge 1s-->3d feature of the X-ray absorption spectrum of the complex. The broad UV/Vis band of this complex in acetonitrile with lambda(max)=648 nm was consistent with a radical cation structure, in which a MCPBA molecule was bound to the Mn(IV) central atom. An oxomanganese(V) or a dimeric manganese(IV) species was not detected.     

碳酸盐前驱物制备Y2O3超细粉及透明陶瓷

以Y(NO3)3和NH4HCO3为原料,通过向Y(NO3)3溶液中滴加NH4HCO3的方式制备了化学组成为Y2(CO3)3·2H2O的先驱沉淀物。研究了先驱沉淀物煅烧过程中的物相变化。先驱沉淀物1100℃煅烧4h后得到了平均粒径为60nm的无团聚Y2O3超细粉体。所得粉体不添加任何添加剂,在1700℃下真空烧结4h得到了透明Y2O3陶瓷。     

peri-Naphthylenediamines. 36. 5,6-Bis(dimethylamino)acenaphthylene in [4+2] cycloaddition reactions. Synthesis and characteristic features of protonation of “proton sponges” with the 8,9-diazafluoranthene structure

5,6-Bis(dimethylamino)acenaphthylene is readily involved in [4+2] cycloaddition reactions with symm-tetrazine derivatives to form new proton sponges with the diazafluoranthene skeleton. Under analogous condition, 1,8-bis(dimethylamino)-4-vinylnaphthalene gave 4-pyridazinyl derivatives. The relative reactivities of 5,6-bis(dimethylamino)acenaphthylene, 1,8-bis(dimethylamino)-4-vinylnaphthalene, 5-dimethylaminoacenaphthylene, and acenaphthylene in the reactions with 3,6-diphenyl-symm-tetrazine are in a ratio of 32 : 17 : 14 : 1. The site of protonation of 3,4-bis(dimethylamino)-7,10-diphenyl-8,9-diazafluoranthene is controlled by the basicity of the solvent. The reaction in acetonitrile afforded the cation stabilized by an intramolecular hydrogen bond, whereas the reaction in dimethyl sulfoxide gave rise to the resonance-stabilized cation. 6,7-Bis(dimethylamino)phenalen-1-one was protonated only at the carbonyl group.     

Macrocyclic cobalt(III) complexes as precursors for metal-polythiophene hybrid materials

A thiophene-functionalised macrocyclic ligand trans-6,13-dimethyl-6-((thiophen-3-ylmethyl)amino)-1,4,8,11-tetraazacyclotetradecane-13-amine (L¹) has been prepared and complexed with Co^III. The ligand L¹ binds as a pentadentate in the crystallographically characterised complexes [CoL¹(OAc)](ClO₄)₂ and [CoL¹Cl]Cl₂. Electro-copolymerisation of [CoL¹Cl]Cl₂ with 3,4-ethylenedioxythiophene (EDOT) in a 1:2 ratio on a preformed poly-3,4-ethylenedioxythiophene (PEDOT) film resulted in metal–polymer hybrid films of high quality, consistency and uniformity in appearance. The copolymerised films were characterised by XPS indicating a 1:11 ratio of incorporation of complex to EDOT. Electrochemistry of the Co-PEDOT film (cast on an indium-doped tin oxide working electrode) in water revealed a Co^III/II redox couple at a potential ca. −600 mV (vs Ag/AgCl) which is similar to that seen in solution for the monomeric aqua complex [CoL¹(OH₂)]³⁺.