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911.
912.
Carlos Camacho‐Camacho Irma Rojas‐Oviedo Ariadna Garza‐Ortiz Jorge Cárdenas Rubén Alfredo Toscano Rubén Gaviño 《应用有机金属化学》2013,27(1):45-51
Two novel triorganotin carboxylate complexes of the biologically active urocanic acid have been synthesized and characterized. Elemental analysis, melting point, spectroscopic techniques – IR, 1H, 13C and 119Sn NMR – mass spectrometry and X‐ray diffraction studies have been used for structural characterization. Crystal structures of the tin(IV) derivatives show that urocanic acid acts as a bridging bidentate ligand through its imidazole nitrogen atom and its carboxylic group, producing a polymeric one‐dimensional chain. The molecular structures of the complexes, catena‐poly‐tri(n‐butyl)tin(IV) 3‐(3H‐imidazol‐4‐yl)prop‐2‐enoate (1) and catena‐poly‐triphenyltin(IV) 3‐(3H‐imidazol‐4‐yl)prop‐2‐enoate (2), present a distorted trigonal–bipyramidal configuration. This is further confirmed by 119Sn NMR in the solid state. The tin(IV) derivatives form double‐stranded ribbons via N―H…O―H bonds. Nevertheless, the compounds are essentially monomeric in solution, with a tetrahedral configuration as observed by 119Sn NMR in solution. The cytotoxic activity of the titled compounds has been tested against six human cell lines and the corresponding IC50 values are reported. Both tin(IV) compounds have a high to very high in vitro cytotoxic activity against the tumor cell lines K562, HCT‐15 and MCF‐7. Compound 1 is 86 times more active than cisplatin in the HTC‐15 cell line. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
913.
Oleg G. Sinyashin Elvira S. Batyeva Oleg V. Ugryumov Ilyas S. Nizamov Olga A. Varnavskaya S. I. Vasyukov 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-3):21-23
Abstract Novel ammonium salts of O,O-dialkyl dithiophosphoric acids were obtained by one-pot synthesis from white phosphorus, elemental sulfur, industrial alcohols or phenols, and amines. Long-chain S-alkyl O,O-dialkyldithiophosphonates were prepared by the reaction of red phosphorus with elemental sulfur, alcohols, and the cheap industrial fractions of С16–С18 and С20–С26 of higher α-olefins in the presence of Lewis acid catalyst. The dithiophosphates obtained possess the high anticorrosion activities toward mild steel. 相似文献
914.
Co‐polymeric hydrogels consisting of N‐vinyl‐2‐pyrrolidone (NVP) and acrylic acid (AAc) were synthesized and evaluated for release of a model drug, i.e., vitamin B12. Release studies in simulated gastric fluid (pH 1.2) and intestinal fluid (pH 7.4), at 37°C, showed the hydrogels to be pH sensitive. An in vitro release study by ‘traditional dissolution test’ (TDT) showed that percent drug released from the hydrogel was nearly 8.6±2.1 and 83.2±4.8 in the media of pH 1.2 and 6.8, respectively. However, in order to incorporate in vivo GI conditions such as acidic pH and high water content in the stomach, low water content and the presence of a semi–solid mass in the large intestine, a new test model, called flow through diffusion cell (FTDC) was also used. The two approaches yielded almost different release profiles. The gels were characterized by thermogravimetric analysis and FTIR spectroscopy. 相似文献
915.
SHEN Hai-yan WANG Hui ZUO Wen-jian ZHAO You-xing LUO Ying MEI Wen-li DAI Hao-fu 《高等学校化学研究》2013,29(3):483-486
A new phenylpropanoid glycoside, named cambodianin F(1), together with three known compounds, 1-O-β-D-glucopyranosyl-2-hydroxy-4-allylbenzene(2), 1-O-(6-O-α-L-rhamnopyranosyl-β-D-glucopyranosyl)-2-hydroxy-4-allylbenzene(3) and 1,2-di-O-β-D-glucopyranosyl-4-allylbenzene(4) was isolated from the dragon's blood of Dracaena cambodiana. The new compound was elucidated by HR-ESI-MS and spectroscopic techniques(UV, IR, 1D and 2D NMR). 相似文献
916.
通过在 CsPbBr3薄膜上旋涂一次 I2的异丙醇溶液以修饰 CsPbBr3吸光层,钝化 CsPbBr3层表面缺陷,改善 CsPbBr3薄膜形貌。同时通过利用环境友好的绿色溶剂水溶解 CsBr,显著提高了其溶解度,减少了旋涂次数,简化了电池制备流程。实验结果表明,在CsPbBr3钙钛矿太阳能电池(perovskite solar cells,PSCs)中,使用5 mg·mL-1 I2的异丙醇溶液界面修饰的器件具有最佳光伏性能,其最高开路电压(open-circuit voltage,VOC)为1.55 V,短路电流密度(short circuit current density,JSC)为7.45 mA·cm-2,填充因子(fill factor,FF)为85.54%,光电转换效率(photoelectric conversion efficiency,PCE)达到了9.88%。 相似文献
917.
Based on a water‐in‐oil‐in‐water emulsion system, porous and hollow polydimethylsiloxane (PDMS) beads containing cells using a simple fluidic device with three flow channels are fabricated. Poly(ethylene glycol) (PEG) in the PDMS oil phase is served as a porogen for pore development. The feasibility of the porous PDMS beads prepared with different PEG concentrations (10, 20, and 30 wt%) for cell encapsulation in terms of pore size, protein diffusion, and cell proliferation inside the PDMS beads is evaluated. The PDMS beads prepared with PEG 30 wt% are exhibited a highly porous structure and facilitated fast diffusion of protein from the core domain to the outer phase, eventually leading to enhanced cell proliferation. The results clearly indicate that hollow PDMS beads with a porous structure could provide a favorable microenvironment for cell survival due to the large porous structure.
918.
919.
Photovoltaic Performance of Triphenylamine Dyes-sensitized Solar Cells Employing Cobalt Redox Shuttle and Influence of π-conjugated Spacers 下载免费PDF全文
Developing photosensitizers suitable for the cobalt electrolyte and understanding the structure-property relationship of organic dyes is warranted for the dye-sensitized solar cells (DSSCs). The DSSCs incorporating tris(1,10-phenanthroline)cobalt(II/III)-based redox elec-trolyte and four synthesized organic dyes as photosensitizers are described. The photovoltaic performance of these dyes-sensitized solar cells employing the cobalt redox shuttle and the influences of the π-conjugated spacers of organic dyes upon the photovoltage and photocur-rent of mesoscopic titania solar cells are investigated. It is found that organic dyes with thiophene derivates as linkers are suitable for DSSCs employing cobalt electrolytes. DSSCs sensitized with the as-synthesized dyes in combination with the cobalt redox shuttle yield an overall power conversion efficiency of 6.1% under 100 mW/cm2 AM1.5 G illumination. 相似文献
920.
Mixed ionic-electronic conductors in the family of LaxSr1–xCoyFe1–yO3–δ have been widely studied as cathode materials for solid oxide fuel cells (SOFCs). However, the long-term stability was a concern. Here we report our findings on the effect of a thin film coating of La0.85Sr0.15MnO3–δ (LSM) on the performance of a porous La0.6Sr0.4Co0.2Fe0.8O3–δ (LSCF) cathode. When the thicknesses of the LSM coatings are appropriate, an LSM-coated LSCF electrode showed better stability and lower polarization (or higher activity) than the blank LSCF cathode without LSM infiltration. An anode-supported cell with an LSM-infiltrated LSCF cathode demonstrated at 825 °C a peak power density of ~1.07 W/cm2, about 24% higher than that of the same cell without LSM infiltration (~0.86 W/cm2). Further, the LSM coating enhanced the stability of the electrode; there was little degradation in performance for the cell with an LSM-infiltrated LSCF cathode during 100 h operation. 相似文献