盐场卤水氧化-吸附联合脱色工艺的研究

以天津汉沽盐场高含镁卤水为研究对象,分析其成色原因,建立了过氧化氢氧化-氢氧化锆吸附联合脱色工艺,分别考察了脱色剂用量、温度、pH值等因素对卤水色度、CODCr及镁离子损失率的影响,确定了最佳的脱色工艺条件:用卤水处理量1%(体积比)的过氧化氢于室温下将卤水氧化2h后,在pH值为2～3的条件下经氢氧化锆吸附脱色40min,氢氧化锆投加用量为60g/L卤水。在此条件下,卤水色度及CODCr去除率分别可达99%和85%,镁离子的损失率可控制在1%以下,均高于目前现行的工艺方法。吸附剂氢氧化锆经脱附后可循环使用,大大降低了工艺运行成本。     

含吸电子基团配体的α-二亚胺-Ni(Ⅱ)上乙烯聚合反应性能

合成了一种新型的含溴α-二亚胺配体及其Ni配合物,并采用核磁共振氢谱、核磁共振碳谱、元素分析、傅里叶变换红外光谱和X射线光电子能谱进行了表征.同时以二乙基氯化铝为助催化剂用于乙烯聚合反应,考察了温度、Al/Ni摩尔比和配体结构对聚合反应性能的影响.结果表明,在25℃,Al/Ni摩尔比为600时,该催化剂活性最高,可达3...     

2-氨基(芳氧基)-3-对甲基苯基噻吩并[3',2':5,6]吡啶并[4,3-d]嘧啶-4(3H)-酮的合成和生物活性

用邻氨基噻吩腈与乙酰乙酸甲酯为原料,利用串联Aza-Wittig法合成了9个未见文献报道的噻吩并吡啶并嘧啶类化合物,通过IR,1H NMR,EI-MS,元素分析等方法对所合成的化合物进行了结构表征,并初步测定了所合成化合物的杀菌活性.生测结果表明:此类化合物对棉花枯萎(Fusarium oxysporium)、水稻纹枯(Rhizoctonia solani)、小麦赤霉(Gibberella zeae)、苹果轮纹菌(Dothiorella gregaria)、棉花炭疽菌(Colletotrichum gossypii)等5种菌均有一定的抑制活性.其中对苹果轮纹菌抑制活性最好,在浓度为5.0×10-5g/mL时抑制率为31.80%～82.84%.     

New octahedral bis-α-diimine nickel(II) complexes containing chloro-substituted aryl groups: Synthesis, characterization and testing as ethylene polymerisation catalysts

Three new 20-electron bis-α-diimine nickel (II) complexes containing chloro-substituted ligands, bis{bis[N,N′-(3-chloro-2-methylphenyl)imino]-1,2-dimethylethane}dibromonickel 2a, bis{bis[N,N′-(3-chloro-2,6-dimethylphenyl)imino]-1,2-dimethylethane}dibromonickel 2b and bis{bis[N,N′-(4-chloro-2,6-dimethyl-phenyl)imino]-1,2-dimethylethane}dibromonickel 2c, were synthesized and characterized. The molecular structure of complex 2a was determined by X-ray crystallography. In the solid state, complex 2a has a pseudo-octahedral geometry about the nickel center, containing two α-diimine ligands in the pseudo-equatorial plane and two trans bromide ligands occupying the axial positions. These complexes, activated by diethylaluminum chloride (DEAC) were tested in the polymerization of ethylene under mild conditions. NMR analysis shows that highly branched polyethylenes are obtained using these bis-α-diimine nickel(II) complexes containing electron-withdrawing Cl groups in the aryl groups (e.g. 84 branches/1000 C, at 20 °C). The catalytic activity, polymer molecular weight and polymer degree of branching were significantly affected by the number of methyl substituents in the ortho-aryl position and the chlorine substituent position in the aryl rings of the coordinated α-diimine ligands.     

Synthesis and Spectroscopy of Novel Branched Fluorescent Dyes Containing Benzophenone Parts and the Possibility as Fluorescence Probes

This paper describes a new fluorescent family of branched dyes containing benzophenone unit including 4-N, N-diphenylamino-4??-phenacyl-stilbene (C1), 4,4??-di(4-benzoylphenylethylene)yl-triphenylamine (C2) and 4,4??,4??-tri(4-benzoylphenylethylene)yl-triphenylamine (C3). Benzophenone part is coupled with core through C?CC double bond. The chemical structures of the derivatives are characterized with ¹H and ¹³C nuclear magnetic resonance and elemental analysis. Strong ?ШC?? stacking interactions are discovered with the analysis of the X-ray crystallographic data of C1. The absorption maxima and emission maxima of the derivatives exhibit gradual bathochromic shift from C1 to C3. The optical density of C1, C2 and C3 are shown to be related to the number of branches. The changes of dipole moments between the excited and ground states for C1, C2 and C3 were estimated to be 4.356, 8.091 and 8.479 Derby, respectively by Lippert equation, confirming that the internal charge transfer (ICT) dominates the process of excited singlet state. The possibility as fluorescence probes of the derivatives on the estimation of what region of micelles interacting with samples was evaluated.     

Chiral nickel(II) and palladium(II) catalysts bearing strong electron‐withdrawing fluorine groups: synthesis,characterization and their application in catalytic polymerization for ethylene and styrene

A series of new chiral and achiral nickel(II) and palladium(II) complexes, {bis[N,N′‐(2,6‐diethyl‐4‐naphthylphenyl)imino]‐1,2‐dimethylethane}dibromonickel 3a , {bis[N,N′‐(4‐fluoro‐2‐methyl‐6‐sec‐phenethylphenyl)imino]‐1,2‐dimethylethane}dibromonickel rac‐(RS)‐ 3b , {bis[N,N′‐(4‐fluoro‐6‐sec‐phenethylphenyl)imino]‐1,2‐dimethylethane}dibromonickel rac‐(RR/SS)‐ 3c and {bis[N,N′‐(4‐fluoro‐6‐sec‐phenethylphenyl)imino]‐1,2‐dimethylethane}dichloropalladium rac‐(RR/SS)‐ 3d were successfully synthesized and characterized. The molecular structures of representative ligand rac‐(RS)‐ 2b , nickel complex 3a , rac‐(RR/SS)‐ 3c and palladium complex rac‐(RR/SS)‐ 3d were determined by X‐ray crystallography. The structures of complexes 3a and rac‐(RR/SS)‐ 3c have pseudo‐tetrahedral geometry about the nickel center, showing C₂ molecular symmetry. However, the structure of palladium complex rac‐(RR/SS)‐ 3d has pseudo‐square planar geometry about the palladium center, showing C₂ molecular symmetry. Complex 3e {bis[N,N′‐(2,6‐dimethylphenyl)imino]‐1,2‐dimethylethane}dibromonickel was also synthesized for comparison. Nickel complex rac‐(RS)‐ 3b bearing strong electron‐withdrawing fluorine group in the para‐aryl position and a chiral sec‐phenethyl group in the ortho‐aryl position of the ligand (one methyl group in the ortho‐aryl position) displays the highest catalytic activity for ethylene and styrene polymerization, and produced highly branched polyethylene and syndiotactic‐rich polystyrene. However, palladium complex rac‐(RR/SS)‐ 3d shows low catalytic activity for ethylene and styrene polymerization due to the poor leaving group, Cl, attached to palladium and the unfavorable molecular structure. Copyright © 2014 John Wiley & Sons, Ltd.     

长沙经济发展的动态分析

本文根据1997~2004年的长沙经济主要指标的时序立体数据表,进行时序全局主成分分析,得到一条动态轨迹并表明和客观实际能较好的吻合,为促进经济的快速发展提供一定的参考依据.     

氢氟酸后处理对Silicalite-1催化环己酮肟气相Beckmann重排反应性能的影响

 研究了氢氟酸后处理对 silicalite-1 催化环己酮肟气相Beckmann重排反应性能的影响. 结果表明,经适当浓度的氢氟酸溶液处理后,催化剂的选择性和稳定性都明显改善. 其中, silicalite-1 原粉先经硝酸铵预处理后再进行氢氟酸后处理所得到的催化剂催化性能最好,反应53 h后环己酮肟的转化率仍保持在96%左右,己内酰胺的选择性高达96.1%. XRD, FT-IR和 29Si MAS NMR的结果表明,较高的具有氢键相互作用的硅羟基与孤立硅羟基的比例值对环己酮肟气相Beckmann重排反应有利,同时, silicalite-1 表面硅原子的排布方式对该反应也有重要影响.     

The direct synthesis of dimethyl ether from syngas over hybrid catalysts with sulfate-modified γ-alumina as methanol dehydration components

A series of γ-Al₂O₃ samples modified with various contents of sulfate (0–15 wt.%) and calcined at different temperatures (350–750 °C) were prepared by an impregnation method and physically admixed with CuO–ZnO–Al₂O₃ methanol synthesis catalyst to form hybrid catalysts. The direct synthesis of dimethyl ether (DME) from syngas was carried out over the prepared hybrid catalysts under pressurized fixed-bed continuous flow conditions. The results revealed that the catalytic activity of SO₄²⁻/γ-Al₂O₃ for methanol dehydration increased significantly when the content of sulfate increased to 10 wt.%, resulting in the increase in both DME selectivity and CO conversion. However, when the content of sulfate of SO₄²⁻/γ-Al₂O₃ was further increased to 15 wt.%, the activity for methanol dehydration was increased, and the selectivity for DME decreased slightly as reflected in the increased formation of byproducts like hydrocarbons and CO₂. On the other hand, when the calcination temperature of SO₄²⁻/γ-Al₂O₃ increased from 350 °C to 550 °C, both the CO conversion and the DME selectivity increased gradually, accompanied with the decreased formation of CO₂. Nevertheless, a further increase in calcination temperature to 750 °C remarkably decreased the catalytic activity of SO₄²⁻/γ-Al₂O₃ for methanol dehydration, resulting in the significant decline in both DME selectivity and CO conversion. The hybrid catalyst containing the SO₄²⁻/γ-Al₂O₃ with 10 wt.% sulfate and calcined at 550 °C exhibited the highest selectivity and yield for the synthesis of DME.