吲哚基丁烯酮缩氨基硫脲配合物的合成及生物活性

缩氨基硫脲类Schiff碱化合物因具有显著的抗菌和抗肿瘤等活性而受到广泛关注,研究发现很多这类化合物与金属离子形成配合物以后,生物活性明显增强。例如,3-乙氧基-2-氧代丁醛双缩氨基硫脲（H2KTs）单独用于治疗大鼠腹水癌瘤没有效果,而H2KTs与铜的配合物则可明显抑制大鼠腹水癌瘤。由于研究这类化合物有重要意义,考虑到吲哚类化合物往往出具有多种生物活性,我们利用拼合原理设计合成了一种带有吲哚基团的缩氨基硫脲Schiff碱配体,并制备了其铜、镍、锌、钴四种边渡金属的配合物,并对配体和配合物的抗菌、抗种瘤活性进行了测试。     

A novel D-A-π-A organic sensitizer containing a diketopyrrolopyrrole unit with a branched alkyl chain for highly efficient and stable dye-sensitized solar cells

A novel D-A-π-A type organic dye (YCD01) incorporating a diketopyrrolopyrrole unit with a branched alkyl chain was synthesized for dye-sensitized solar cells. YCD01 showed a high conversion efficiency of 7.43% (AM 1.5, 100 mW cm(-2)) with a J(sc) of 13.40 mA cm(-2), a V(oc) of 0.76 V, a FF of 0.73 and an excellent stability.     

N-(ω-三甲基硅烷基醚)马来酰亚胺的光诱导单电子转移反应

合成了两个N-(ω-三甲基硅烷基醚)马来酰亚胺衍生物(2a,2b),并以2a,2b为光反应底物在HCN,MeOH,30%H2O-HCN,丙酮等溶剂中进行了光反应.结果显示,化合物2a在强的亲硅性溶剂MeOH,30%H2O-MeOH,30%H2O-HCN中经单电子转移反应以很高的产率和区域选择性生成环胺醇产物3,在HCN...     

Studies of interaction between colchicine and bovine serum albumin by fluorescence quenching method

We investigated the interaction between colchicine and bovine serum albumin (BSA) by fluorescence and UV–Vis absorption spectroscopy. In the mechanism discussion, it was proved that the fluorescence quenching of BSA by colchicine is a result of the formation of colchicine–BSA complex; van der Waals interactions and hydrogen bonds play a major role in stabilizing the complex. The modified Stern–Volmer quenching constant K_a and corresponding thermodynamic parameters ΔH, ΔG, ΔS at different temperatures were calculated. The distance r between donor (BSA) and acceptor (colchicine) was obtained according to fluorescence resonance energy transfer (FRET).     

On the vanishing of the Lannes–Zarati homomorphism

The conjecture on spherical classes states that the Hopf invariant one and the Kervaire invariant one classes are the only elements in H_?(Q₀S⁰)$H_{?}(Q_0{S}^0)$ belonging to the image of the Hurewicz homomorphism. The Lannes–Zarati homomorphism is a map that corresponds to an associated graded (with a certain filtration) of the Hurewicz map. The algebraic version of the conjecture predicts that the s  -th Lannes–Zarati homomorphism vanishes in any positive stems for s>2$s>2$. In the article, we prove the conjecture for the fifth Lannes–Zarati homomorphism.     

Synthesis of ZnO nanomaterials with controlled morphology and their photoelectrochemical properties

Three morphologies of ZnO nanomaterials (ZnO-hand grenade, ZnO-rod and ZnO-particle) were synthesized via a facile hydrothermal method. The as prepared ZnO nanomaterials were used as photoelectrodes to fabricate dye sensitized solar cells (DSSCs). Of the three samples, ZnO-particle displays the highest photovoltaic conversion efficiency which can be attributed to the high surface area to absorb light more efficiently. Intensity modulated photocurrent spectroscopy (IMPS), and intensity-modulated voltage spectroscopy (IMVS) indicate that ZnO-rod provides superior electron transfer kinetics: fast electron transfer and long electron lifetimes with suppressed recombination.     

Enhanced Thermoelectric Properties of Polyaniline Nanofilms Induced by Self‐Assembled Supramolecules

Polyaniline (PANI) is one of the most promising candidates for flexible organic thermoelectric (TE) applications owing to its relatively low cost and high stability. Herein, the self‐assembled supramolecule (SAS) (3,6‐dioctyldecyloxy‐1,4‐benzenedicarboxylic acid) was used as an additive and was introduced into PANI films as a template. Raman spectroscopy, X‐ray diffraction, and conductive atomic force microscopy analyses demonstrated that the highly ordered chain structure of PANI was achieved by chemical interactions between PANI and the SAS. Moreover, the ordered regions in the PANI‐SAS film increased with a decrease in the film thickness. Consequently, the TE properties of PANI‐SAS films were not only much higher than those of PANI films, but they also increased with a decrease in film thickness. The maximum TE power factor of the PANI‐SAS film reached 31 μW m^?1 K^?2, which is approximately six times higher than the power factor of a PANI film with a similar thickness. This work offers a promising way to prepare PANI thin films with enhanced TE properties.     

丙酰胺氯化稀土配合物及其氯化钕配合物催化丁二烯聚合的活性

合成了组成为ＬｎＣｌ３·３ＰＡ的丙酰胺氯化稀土配合物（Ｌｎ＝Ｐｒ，Ｎｄ，Ｅｕ，Ｄｙ；ＰＡ＝Ｃ２Ｈ５ＣＯＮＨ２）．ＩＲ表明，丙酰胺是通过酰胺基团的Ｏ与Ｎｄ进行配位．ＮｄＣｌ３·３ＰＡ配合物与烷基铝组成的二元体系，无论是三异丁基铝，二异丁基氢铝或者是三乙基铝都对丁二烯聚合具有较高的催化活性，而且所得聚丁二烯的顺式－１，４结构含量都在９８％以上．     

Undersampled MRI reconstruction with patch-based directional wavelets

Compressed sensing has shown great potential in reducing data acquisition time in magnetic resonance imaging (MRI). In traditional compressed sensing MRI methods, an image is reconstructed by enforcing its sparse representation with respect to a preconstructed basis or dictionary. In this paper, patch-based directional wavelets are proposed to reconstruct images from undersampled k-space data. A parameter of patch-based directional wavelets, indicating the geometric direction of each patch, is trained from the reconstructed image using conventional compressed sensing MRI methods and incorporated into the sparsifying transform to provide the sparse representation for the image to be reconstructed. A reconstruction formulation is proposed and solved via an efficient alternating direction algorithm. Simulation results on phantom and in vivo data indicate that the proposed method outperforms conventional compressed sensing MRI methods in preserving the edges and suppressing the noise. Besides, the proposed method is not sensitive to the initial image when training directions.     

A multiple-function stationary phase based on perhydro-26-membered hexaazamacrocycle for high-performance liquid chromatography

A perhydro-26-membered hexaazamacrocycle-based silica (L¹GlySil) stationary phase for high-performance liquid chromatography (HPLC) was prepared using 3-glycidoxypropyltrimethoxysilane as coupling reagent. The structure of new material was characterized by infrared spectroscopy, elemental analysis and thermogravimetric analysis. The chromatographic performance and retention mechanism of the new phase were evaluated in reversed-phase (RP) and normal-phase (NP) modes using different solute probes including aromatic compounds, organophosphorus pesticides, carbamate pesticides and phenols. The results showed that L¹GlySil was a sort of multimode-bonded stationary phase with excellent chromatographic properties. The new phase could provide various action sites for different solutes, such as hydrophobic, hydrogen bonding, π–π, dipole–dipole interactions and acid–base equilibrium. The presence of phenyl rings, secondary amino groups and alkyl linkers in the resulting material made it suitable for the separation of above-mentioned analytes by multimode retention mechanisms.