A novel N–O ligand for palladium-catalyzed Mizoroki–Heck reaction in neat water

1-(Morpholin-1-yl-pyridin-2-yl-methyl)-2-naphthol as a novel efficient N–O ligand has been developed for palladium-catalyzed Mizoroki–Heck reaction in neat water without the protection of an inert atmosphere. The reactions proceed smoothly and give the desired products in moderate to excellent yields. The catalyst system is reusable.     

Spatial regularity of semigroups generated by Lévy type operators

We apply the probabilistic coupling approach to establish spatial regularity of semigroups associated with Lévy type operators, by assuming that the corresponding martingale problem is well posed. In particular, we can prove the Lipschitz continuity of the associated semigroups, when the coefficients are Hölder continuous but the corresponding Lévy kernel may be singular.     

仿生各向异性聚(N-异丙基丙烯酰胺)水凝胶智能响应驱动器的研究进展

各向异性水凝胶在外界的响应刺激下可以具有不同的反应机制与驱动过程. 本文综述了近期基于PNIPAM水凝胶智能响应驱动器的设计方法, 总结了多种各向异性结构对驱动性能的影响, 并对该领域所面临的挑战进行了讨论.     

机载激光测深回波信号的处理和研究

对激光海洋测深信号特性进行了分析,采用变增益法预处理机载激光测深回波信号,可以压缩水面激光反射信号的光通量与水底目标返回信号光通量的动态范围,实验结果使其动态压缩范围达10³～10⁴量级,满足机载蓝绿激光测深的要求。     

Quantification of gold(III) in solution and with a test stripe via the quenching of the fluorescence of molybdenum disulfide quantum dots

The paper describes a fluorescent method for determination of Au(III) using molybdenum disulfide quantum dots (MoS₂ QDs) that were prepared by a hydrothermal route using glutathione as a reductant. The photoluminescence of MoS₂ QDs peaks at 416 nm if excited at 340 nm and is temporally stable even in presence of NaCl or when stored in the refrigerator for one year. Its quantum yield is 12.7 %. The blue-green fluorescence of MoS₂ QDs is fairly specifically quenched by Au(III) ions and therefore presents a useful nanoprobe for this ion. Fluorescence intensity drops linearly with the concentration of Au(III) in the range from 0.5 to 1000 μM, and the lower detection limit is 64 nM. The quenching mechanism was investigated and it is concluded that the process is due to the reduction of Au(III) and the deposition of Au(0) on the surface of the MoS₂ QDs. The nanoprobe was successfully applied to the determination of Au(III) in (spiked) environmental samples. A test stripe for Au(III) was obtained by soaking a piece of paper with a colloidal solution of the MoS₂ QDs, and it was found that this stripe, after drying, can also be used to quantify Au(III) via fluorescence.

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Graphical abstract Molybdenum disulfide quantum dots (MoS₂ QDs) have a high quantum yield and show good stability. MoS₂ QDs are shown to be a sensitive fluorescent probe for the determination of Au³⁺ ions in solution and with a test stripe via fluorescence quenching.

     

Efficient decomposition of sulfamethoxazole in a novel neutral Fered-Fenton like/oxalate system based on effective heterogeneous-homogeneous iron cycle

Based on effective heterogeneous-homogeneous iron cycle, efficient SMX degradation was achieved in a novel neutral Fered-Fenton like system adopting Ti@TiO₂ cathode.     

三（8－羟基喹啉）镍（Ⅱ）合高氨酸钠Na［NiQ_2（HQ）］（ClO_4）的制备和晶体结构

在使用８－羟基喹啉为配体试图制备钆和镍的异双核配合物时，分离出Ｎａ［ＮｉＱ２（ＨＱ）］（ＣｌＯ４）单晶，首次测定了它的晶体结构．Ｒａｎｅ等曾从ＮｉＱ２·２Ｈ２Ｏ的晶胞参数推测出ＮｉＱ２·２Ｈ２Ｏ的键参数［１］．最近我们将高氯酸钇、醋酸镍和８－羟基喹啉在丙酮中反应，制备了［ＹＱ（ＨＱ）２］［ＮｉＱ３（ＣｌＯ４），并测定了它的晶体结构［２］     

奥美拉唑对映体在自制手性柱上吸附等温线的测定

采用吸附-脱附法研究了奥美拉唑对映体在自制的纤维素三苯基氨基甲酸酯涂敷型手性柱上的吸附性能,并用Langmuir方程拟合出吸附平衡方程.当样品浓度降低时,Langmuir方程退化为直线关系,直线斜率即为吸附平衡常数.这一吸附平衡常数与从脉冲色谱流出曲线求得的吸附平衡常数相等,表明吸附-脱附法测得的吸附平衡关系准确,Langmuir方程能描述这一吸附平衡关系.     

7，7，8，8－四氰基对苯醌二甲烷与邻菲咯啉稀土配合物的合成和表征

７，７，８，８－四氰基对苯醌二甲烷与邻菲咯啉稀土配合物的合成和表征张明杰，聂玉敏，史志勤，张文胜，梁惠来（天津大学化学系天津３０００７２）（天津大学电子工程系天津）关键词四氰基对苯酮二甲烷，邻菲咯啉，镧配合物，钕配合物，合成７，７，８，８－四氰基对苯...