Highly selective two-photon chemosensors for fluoride derived from organic boranes

[reaction: see text] Three organoboron compounds are shown to be two-photon fluorescent sensors for fluoride anion with high sensitivity and selectivity. The recognition mechanism is attributed to the unique steric structure of the bulky dimesitylboryl group and the Lewis acid-base interaction between trivalent boron atom and fluoride anion.     

Ionic Liquid Based Electrolyte with Mesoporous Silica SBA-15 as Framework for Quasi-solid-state Dye-sensitized Solar Cells

Quasi-solid-state electrolytes were fabricated with mesoporous silica SBA-15 as a framework material. Ionic conductivity measurements revealed that SBA-15 can enhance the conductivity of the quasi-solid-state electrolyte. The diffusion coefficients of polyiodide ions such as Ⅰ3ˉ and Ⅰ5ˉ which were confirmed by Raman spectroscopic measurement, were about twice larger than that of I-. The optimized photoenergy conversion efficiency of dye-sensitized solar cells （DSSC） with the quasi-solid-state electrolyte was 4.3% under AM 1.5 irradiation at 75 mW·cm^-2 light intensity.     

新型两亲性混配钌配合物的合成及其对Hg2+的选择性“肉眼”识别

采用与文献不同的路线合成了4,4′-二(p-甲基苯基)-2,2′-二联吡啶,与文献结果相比,总收率由4.0%提高至15.3%.该化合物和4,4′-二羧基-2,2′-二联吡啶组成混合配体与金属钌配位,合成了两亲性、混配型配合物cis-N,N-4,4′-二(p-甲基)苯基-2,2′-二联吡啶-N,N-4,4′-二羧基-2,2′-二联吡啶-N,N-二异硫氰钌配合物,并用IR,UV-Vis,NMR和Maldi-TOF等手段进行表征.将该两亲性混配钌配合物首次用于对Hg2+的识别中,发现此配合物对Hg2+表现出灵敏的选择性“肉眼”识别:在DMF/乙醇溶液(体积比1∶9)中加入Hg2+后,MLCT态吸收由530nm蓝移到485nm.该配合物与Hg2+以1∶1(摩尔比)结合,检测限可低至0.5×10-6mol/L.     

Photosensitization of nanocrystalline TiO2 electrodes with II B group metal-ion-bridged self-assembled films of 3,4,9,10-perylenetetracarboxylic acid

Self-assembled films (SA films) of 3,4,9,10-perylenetetracarboxylic acid (PTA) (Film P) and II B group metal-ion-bridged PTA (Film PMP, M=Zn²⁺, Cd²⁺, or Hg²⁺) were fabricated on nanocrystalline TiO₂ electrodes and characterized with UV–VIS and IR spectra and XPS. Compared with Film P sensitized solar cell, Grätzel cells based on individual PMP electrodes are more efficient regarding photocurrent generation. Synchrotron radiation photoelectron spectroscopy (SRPES) study reveals that those HOMO energy levels of PMP films are greater than that of Film P. The higher HOMO energy levels will lead to higher excited state energy levels that benefit electron injection, and hence, increase efficiencies for photocurrent generation. In view of the invariable valence of Zn²⁺, Cd²⁺, and Hg²⁺ ions, electron injection should be attributed to ligand, but not to the central metal ions, like the case of Ru(II)–bipyridyl complex.     

Ionic liquid aqueous solvent-based microwave-assisted hydrolysis for the extraction and HPLC determination of myricetin and quercetin from Myrica rubra leaves

An ionic liquid aqueous solvent‐based microwave‐assisted hydrolysis (ILAS‐MAH) approach was proposed for the rapid extraction and accurate determination of myricetin and quercetin from Myrica rubra (M. rubra) leaves for the first time. The effects of the ionic liquid class and concentration, liquid–solid ratio, hydrolysis temperature and time were investigated to obtain the optimal ILAS‐MAH conditions. The optimized conditions were 2.0 mol/L [bmin][HSO4] or 2.5 mol/L acidified [bmin]Br solution, liquid–solid ratio 30:1 (mL : g), hydrolysis temperature 70°C and hydrolysis time 10 min. Under these conditions, the recoveries of myricetin and quercetin were in the range of 86.3–107.3% with relative standard deviation lower than 5.8%. Compared with conventional heating hydrolysis and regular MAH, the proposed approach reduced hydrolysis time and improved yields. The mechanism of ILAS‐MAH was also investigated. Copyright © 2010 John Wiley & Sons, Ltd.     

三聚氰胺金属(Ⅱ)配合物的结构、紫外-可见光谱和反应活性

三聚氰胺是婴幼儿"肾结石事件"的重要前体.本文选取几个典型的二价金属离子与三聚氰胺(L)形成的三聚氰胺金属配合物ML2(OH)2(M=Ca,Mg,Zn,Cu,Ni,Fe),使用密度泛函理论(DFT)、含时DFF和概念DFT等工具,系统地计算和比较了ML2(OH)2的结构、紫外-可见光谱和反应性质的异同.模拟结果揭示了ML2(OH)2的结构、光谱及其反应性质是一类不同于其前体L,形成ML2(OH)2配合物后,将有较高的亲电指数和较低的化学硬度以及呈现红外吸收峰红移;在这些典型的二价金属配合物中,金属M离子电荷与配体O和N原子之间的电荷、以及与金属M离子和配体原子之间的二级微扰相互作用能,配合物最低空轨道能级与其亲电反应指数、最低空轨道能级与化学硬度指数等方面,存在着一系列定量的相关关系,相关系数(R2)达0.889-0.997;前线分子轨道模拟结果表明,ML2(OH)2体系反应活性的差异源于金属离子对前线轨道贡献有所不同,FeL2(OH)2、CuL2(OH)2、NiL2(OH)2等过渡金属离子的配合物中,金属离子贡献较多,共价性成分较多.这些结果将为进一步理解人体内三聚氰胺致结石的成因提供有益的启示.     

对氯苯肼盐酸盐的合成工艺

对氯苯肼盐酸盐;工业合成;对氯苯肼盐酸盐的合成工艺     

Synthesis, Crystal Structure and Antibacterial Activities of 3-[3-Methyl-（2-thienyl）methyl-enehydrazinocarbonyl]-（1H）-1,2,4-triazole

1 INTRODUCTION Azole derivatives, such as the derivatives of pyra- zole, imidazole, triazole including benzotriazole, te- trazole and indole, have extensive biological activi- ties. They have become the central focus of studies of agricultural chemicals, medicines, plant growth regulating agents and so on[1, 2]. Schiff bases also constitute a good type of biologically active sub- structures. Studies on pyrazole Schiff base-type fun- gicides have been reported[3, 4]. However, some struc- …     

二氧化硅-共聚物杂化荧光纳米材料用于动物活体成像

以氧化硅(SiO_2)前驱体与三嵌段共聚物F108合成较小粒径的SiO_2-共聚物杂化纳米体系(SNP),并与高效近红外发射的疏水染料M507自组装,构建了近红外发光纳米探针M507@SNP。同时,研究了M507@SNP的光物理性能和细胞毒性。动物成像实验证明该纳米成像探针可实现活体层次高信噪比的小动物全身成像和前哨淋巴结的指示。     

Multifunctional Molecular Material Combining Photocurrent Generation and Second-Order Optical Nonlinearity in LB Monolayer Films

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