芥子气模拟剂2-氯乙基乙基硫醚的光催化降解

利用连续流动微反、原位红外和GC/MS等手段考察了芥子气模拟剂2-氯乙基乙基硫醚（2-CEES）在P25 TiO2上的光催化降解反应,证实CO2和H2O是这个反应的最终产物.详细的跟踪分析表明,除了CO2和H2O外,在反应的气相混合物中可检测到C2H4、CH3CHO、CH4、CO、HCl和H2S；少量小分子的羧酸、醚和砜；微量C2H5SC2H5、C2H5S2C2H5、C2H5SC2H4Cl和CH2ClCH2Cl等中间产物;在反应后的催化剂表面可检测到C2H5S2C2H5、C2H5SC2H4OH、C4H9S2C2H5和C2H5S2C2H4OH、等物.根据这些结果提出了2-CEES光催化降解的反应机理,推断2-CEES的光催化降解涉及脱氯、C－S键断裂、有机硫化物光聚合和裂解等复杂过程最终转化为CO2和H2O.认为各种硫物种在表面的积聚引起了催化剂的缓慢失活.     

Synthesis of a transition metal-dithionite complex, (η5-C5H5)(CO)2FeS(O)2S(O)2Fe(CO)2(η5-C5H5)

The reaction of Na[η⁵-C₅H₅Fe(CO)₂] with large excess of SO₂ in THF at ?78°C followed by warming to room temperature affords an iron—dithionite complex, (η⁵-C₅H₅)(CO)₂FeS(O)₂S(O)₂Fe(CO)₂(η⁵-C₅H₅).     

CO2部分氧化乙烷制乙烯Pd—Cu／MoO3—SiO2催化剂的研究

用化学吸附－红外光谱、化学吸附－程序升温脱附（ＴＰＤ）和微型反应技术研究了Ｐｄ－Ｃｕ／ＭｏＯ３－ＳｉＯ２（ＭｏＳＯ）催化剂对ＣＯ２和乙烷的吸附活化和部分氧化反应性能．结果表明，乙烷以Ｃ—Ｈ键中的Ｈ吸附于ＭｏＳＯ载体表面ＭｏＯ键的端基氧上；Ｐｄ－Ｃｕ／ＭｏＳＯ催化剂对ＣＯ２有良好的化学吸附活化性能，ＣＯ２的吸附除有线式吸附态和剪式吸附态外，还有一种新的卧式吸附态；Ｐｄ－Ｃｕ／ＭｏＳＯ催化剂的晶格氧参与了化学反应．探讨了在Ｐｄ－Ｃｕ／ＭｏＳＯ催化剂上ＣＯ２的部分氧化乙烷反应机理     

Synthesis and characterization of Mn2P2S6 single-crystal nanorods and nanotubes

Mn2P2S6 single-crystal nanorods with diameters 20-40 nm and lengths up to 1 microm and nanotubes with diameters 40-50 nm and lengths ranging between 110 and 170 nm have been prepared through a low-temperature solvothermal method. They have been characterized by X-ray diffraction, transmission electron microscopy (TEM), high-resolution (HR) TEM, electron diffraction, energy-dispersive spectrometry analysis, X-ray photoelectron spectroscopy, and Raman spectroscopy.     

K3Na5(H2NCH2CH2NH3)2{(VO)12O6[B3O6(OH)]6}(H2O)•12H2O的合成与晶体结构

利用水热合成技术成功制备出一种新型多钒硼氧化合物， 用X射线单晶衍射分析技术对其晶体结构和分子结构进行了确定。结果表明在该化合物中多钒硼氧阴离子具有一个新颖的三明治结构。上下两个结构单元都是由六个VO₅四角锥交替地通过顺式和反式共边的方式连接起来构成的一个钒氧三角形结构。中间的结构单元是由BO₃平面三角形和BO₄四面体以共角的方式相互连接形成的一个折叠型的B₁₈O₃₆(OH)₆环。三明治结构中层与层之间通过桥氧相连。一个水分子处于它的核心位置上，与每个VO₅四角锥中的钒原子都保持几乎相等的距离。该化合物及其晶体中存在着丰富的化学结构和成键信息，同时也有作为氧化还原反应催化剂的潜能。     

Orthogonal PbS nanowire arrays and networks and their Raman scattering behavior

Three-dimensional, orthogonal lead sulfide (PbS) nanowire arrays and networks have been prepared by using a simple, atmospheric pressure chemical vapor deposition (APCVD) method. These uniform nanowires (average diameter 30 nm) grow epitaxially from the surface of the initial PbS crystal seeds and form orthogonal arrays and networks in space. The growth mechanism has been explored, and the process was classified as homogeneous, epitaxial growth in the 200 directions. Furthermore, Raman spectra of PbS nanowires are reported here, and their characteristic Raman peak (190 cm(-1), no shoulder) could be used as a unique probe for the study of PbS nanomaterials.     

The Mechanism on Cyclization, Debenzylation and Oxidation of 1-[1-（Benzyloxy）-3-methylnaphthalen-4-yloxy]propan-2-one

Mansonone compounds represent a series of naturally occurring o-quinones mainly isolated from the heartwood of Mansonia Altissima1 and Ulmus Glabra2. Mansonone F contained oxaphenalene skeleton which was a relatively novel structure and rarely existed in …     

Selective Oxidation of Methane to Methanol Using Molecular Oxygen on MoOx／（LaCoO3＋Co3O4） Catalysts

Comparatively high CH3OH selectivity (60.0%) and yield (6.7%) were obtained on MoOx/(LaCoO3 Co3O4) catalysts in selective oxidation of methane to methanol using molecular oxygen as oxidant. The interaction between MoOx and La-Co-oxide modified the molecular structure of molybdenum oxide and the ratio of O^-/O^2- on the catalyst surface, which controlled the catalytic performance of MoOx/(LaCoO3 Co3O4) catalysts.     

STUDY ON STYRENE-BUTADIENE BLOCK COPOLYMER FOR THE MODIFICATI0N OF TIRE TREAD

This paper mainly deals with the design and synthesis of a novel styrene-butadieneblock copolymer. When this copolymer is used in the tread portion of tyres, it can improvewet skid resistance and reduce rolling resistance without sacrificing its general physical-mechanical properties. The visco-elastic curve of tire tread using the novel copolymer asits rubber portion was showed. Reactivity ratios for two monomers in the polymerizingsystem were calculated. The diagrams of differelitial, integral and finite difference calculithroughout the whole molecular chain were presented. The influence of the micro- andmacro-structure of the copolymer chain on wet skid resistance and rolling resistance wasdiscussed     

Catalytic phenomena in the electrochemical reduction of triphenylphosphine and triphenylphosphine oxide in non-aqueous solvents with tetraalkylammonium supporting electrolytes

Polarography, cyclic voltammetry and coulometry reveal that a catalytic reduction of the tetraalkylammonium cation, R₄N⁺, of the supporting electrolyte is involved in the electrochemical reduction of triphenylphosphine (TPP) and its oxide (TPPO) in aprotic solvents such as acetonitrile, dimethylformamide and hexamethylphosphoramide. There is however progressive consumption of TPP and TPPO resulting in the final formation of phenyl substitution products (RPØ₂ and ROPØ₂). Comparison with the reduction of the BuPØ₃⁺ cation allows to propose the following mechanism which involves a chemical type catalytic process:

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Redox type catalytic mechanisms are discussed and shown to be unlikely. Values of the alkylation rate constant are derived from the polarographic or the coulometric data or from cyclic voltammetry according to its magnitude which varies with the solvent. TPP anion radical appears as more readily alkylable than TPPO anion radical.