分子氧为氧化剂磷钒酸盐为催化剂超深度氧化脱除柴油中的二苯并噻吩

一种“双帽Keggin型”磷钒酸盐在温和的反应条件下以分子氧为氧化剂氧化二苯并噻吩至二苯并噻吩砜的反应中表现出很高的催化活性. 用溶剂萃取或者选择吸附等方法可轻易地将反应产生的二苯并噻吩砜从油品中除去. 这提供了一种新型的分子氧为氧化剂的超深度氧化脱硫方法.     

Analysis of baicalein, baicalin and wogonin in Scutellariae radix and its preparation by microemulsion electrokinetic chromatography with 1-butyl-3-methylimizolium tetrafluoborate ionic liquid as additive

Microemulsion electrokinetic chromatography (MEEKC) using 1-butyl-3-methylimidazolium tetrafluoroborate (BMIM-BF4) ionic liquid (IL) as additive was developed for the analysis of baicalin, wogonin and baicalein in Scutellariae radix and its preparation. After conducting a series of optimizations, baseline separation was obtained for the analytes within 5min under the optimum conditions (sodium dodecyl sulfate (SDS) 0.88% (m/v) ethyl acetate 0.8% (v/v) butan-1-ol 0.2% (v/v) and the buffer composition were 25% acetonitrile (v/v), 7.5 mM BMIM-BF4 and 10 mM NaH2PO4, pH 8.2, applied voltage 17.5 kV and detection at 254 nm), the method has been successfully applied to the determination and quantification of the analytes in the extracts of S. radix (cooked), S. radix (raw) and Qingfeiyihuowan which was the preparation including S. radix.     

Catalytic activity of halohydrin dehalogenases towards spiroepoxides

A novel activity of halohydrin dehalogenases towards spiroepoxides has been found. The enzyme from Arthrobacter sp. (HheA) catalysed highly regioselective azidolysis of spiroepoxides containing 5, 6 and 7-membered cycloalkane rings, while the enzyme from Agrobacterium radiobacter (HheC), besides high regioselectivity, also displayed moderate to high enantioselectivity (E up to >200) that can be applied for the kinetic resolution of chiral spiroepoxides. The orientations of spiroepoxides in the active site of halohydrin dehalogenases were studied by quantum-chemical calculations and docking simulations. Analyses of the complexes obtained revealed the origins of diastereoselectivity and enantioselectivity of the investigated biotransformations.     

铽-噻吩甲酰三氟丙酮-聚丙烯酸的结构及荧光性质

将铽的有机配合物NaTb(TTA)4与聚丙烯酸反应获得铽配位聚合物（Tb-TTA-PAA)。此配位聚合物是褐色固体，不溶于大部分有机溶剂，只能溶于丙三醇和异丙醇的混合溶剂。采用红外光谱、紫外光谱、X射线光电子能谱、电导率、元素分析和荧光光谱等手段对其结构进行表征，确定其配位组成和结构即每个铽离子分别与一个TAA^-离子和PAA分子中二个链节羧基发生配位，得到该配合物的结构。Tb^3 离子在配合物Tb-TTA-PAA中含量为29.98%。荧光光谱表明，常温下配合物在紫外光下发出强荧光，主要是Tb离子的^5D4→^7F5的能量传递。     

基于核酸探针的光学传感方法和细胞成像研究

许多疾病的特征在于各种生物分子表现出的异常活性,这些物质通常在细胞内外显示过表达现象,因此对其灵敏靶向识别可以提供诊断和治疗效用。由于基因诊疗和化学传感技术的发展,用于灵敏检测细胞内外生物化学物质的核酸探针突显优势。核酸探针可以在稳定进入细胞的同时,特异性地结合目标物质,通过光学方法检测或通过成像技术标识出来。本文综述了采用光学传感方法和成像技术,基于核酸探针检测生物分子的新进展。根据检测对象进行分类,概括分析了几个代表性体系:核酸序列、蛋白质和酶、化学物质和物理化学条件,并详细阐述其关键设计原理、灵敏度及样品检测等结果,同时指出了各类核酸探针的优缺点。     

CO/light dual-activatable Ru(ii)-conjugated oligomer agent for lysosome-targeted multimodal cancer therapeutics

Stimuli-activatable and subcellular organelle-targeted agents with multimodal therapeutics are urgently desired for highly precise and effective cancer treatment. Herein, a CO/light dual-activatable Ru(ii)-oligo-(thiophene ethynylene) (Ru-OTE) for lysosome-targeted cancer therapy is reported. Ru-OTE is prepared via the coordination-driven self-assembly of a cationic conjugated oligomer (OTE-BN) ligand and a Ru(ii) center. Upon the dual-triggering of internal gaseous signaling molecular CO and external light, Ru-OTE undergoes ligand substitution and releases OTE-BN followed by dramatic fluorescence recovery, which could be used for monitoring drug delivery and imaging guided anticancer treatments. The released OTE-BN selectively accumulates in lysosomes, physically breaking their integrity. Then, the generated cytotoxic singlet oxygen (¹O₂) causes severe lysosome damage, thus leading to cancer cell death via photodynamic therapy (PDT). Meanwhile, the release of the Ru(ii) core also suppresses cancer cell growth as an anticancer metal drug. Its significant anticancer effect is realized via the multimodal therapeutics of physical disruption/PDT/chemotherapy. Importantly, Ru-OTE can be directly photo-activated using a two-photon laser (800 nm) for efficient drug release and near-infrared PDT. Furthermore, Ru-OTE with light irradiation inhibits tumor growth in an MDA-MB-231 breast tumor model with negligible side effects. This study demonstrates that the development of an activatable Ru(ii)-conjugated oligomer potential drug provides a new strategy for effective subcellular organelle-targeted multimodal cancer therapeutics.

The anticancer therapeutics of lysosome disruption/PDT/chemotherapy based on Ru-OTE complex was achieved, which provides a new strategy for developing multimodal and effective stimuli-activatable subcellular organelle-targeted cancer therapeutics.     

4H-SiC中基面位错发光特性研究

本文利用阴极荧光(CL)和选择性刻蚀的方法对4H-SiC同质外延材料中基面位错的发光特性进行了研究. 结果表明螺型基面位错(B_TSD)和混合型基面位错(B_MD)分别具有绿光和蓝绿光特性,其发光峰分别在530 nm附近和480 nm附近. 从测试结果中还发现B_MD 的发光位较B_TSD有所蓝移,分析认为B_TSD位错芯附近原子沿伯格斯 关键词： 4H-SiC 基面位错 发光特性 禁带宽度     

采用快速升温烧结方法生长Tl-1223超导薄膜的研究

报道了在铝酸镧(00l)衬底上生长Tl-1223超导薄膜的快速升温烧结方法以及铊(Tl)源陪烧靶的配比对Tl-1223薄膜晶体结构的影响.扫描电子显微镜观测表明,采用快速升温烧结方法生长的Tl-1223超导薄膜具有致密的晶体结构.X-射线衍射等测试表明,采用合适配比的陪烧靶在氩气环境下可以制备出纯c轴取向的Tl-1223超导薄膜,充氧退火后的薄膜具有较好的电学性能,其临界转变温度T_(c onset)达到116K,临界电流密度达到1.5MA/cm~2(77 K,0 T).实验结果表明,采用这一新的烧结方法制备Tl系超导薄膜具有升降温时间和恒温时间短、生产成本低等特点.