Order from Chaos: Self‐Assembly of Nanoprism from a Mixture of Tetratopic Terpyridine‐Porphyrin Conformers

Porphyrins have been widely used in the self‐assembly of metallo‐supramolecules. In this study, we introduced 2,2':6,2"‐terpyridine (tpy) into a porphyrin core to synthesize a tetratopic building block with multiple conformers. During the self‐assembly with Zn(II), such a mixture of conformers was able to form a discrete nanoprism with all building blocks in one conformation. Detailed characterizations, including NMR, ESI‐MS and traveling‐wave ion mobility‐mass spectrometry (TWIM‐MS), all supported the formation of the desired assemblies. AFM and TEM further confirmed the dimensions of assembled nanoprisms. Moreover, the photophysical properties of the ligands and complexes were noticeably different depending upon size and metal ion center.     

Development of ELISA and immunochromatographic assay for ofloxacin

Two rapid,sensitive and reliable immunoassay methods,namely competitive indirect enzyme-linked immunosorbent assay(CI- ELISA)and colloidal gold-based immunochromatographic assay(CGIA),were developed to detect ofloxacin(OFL).The linear range of the CI-ELISAwas from 0.5 to 128 ng/mL with a limit of detection(LOD)of 0.35 ng/mL.Good recoveries were obtained in analyzing simulated swine urine samples.The CGIA could accurately estimate OFL at concentrations as low as 10 ng/mL in less than 10 min,and test results were read visually without any instrument.     

基于天然氨基酸的双环手性季铵盐相转移催化剂的合成及催化性能研究

以L－脯氨酸及L－羟基脯氨酸为原料合成了4个新型手性季铵盐磁相转移催化 剂，并用于催化不对称查耳酮环氧化反应，高产率得到相应环氧化合物，ee最高达 9％。     

Fourier transform infrared reflection-absorption spectroscopy of amino acids adsorbed on metal surfaces

Fourier transform infrared reflection-absorption spectroscopy (FT-IRAS) has been used to study the orientation and coordination of glycine, L-phenylalanine and L-histidine on gold and copper surfaces. It was found that glycine and L-histidine were weakly adsorbed (physisorbed) in the zwitterionic form on gold. The surface chemical bonding of L-histidine and L-phenylalanine to copper were chemical rather than physical by nature. Conclusive evidence was obtained for coordination to copper through both the amino-nitrogen and carboxylate-oxygen atoms.     

Synthesis and crystallization kinetics of the novel ion exchanger Na<Subscript>4</Subscript>Ti<Subscript>4</Subscript>Si<Subscript>3</Subscript>O<Subscript>10</Subscript> for cesium removal

Thermodynamics and crystallization kinetics of the hydrothermal synthesis of Na₄Ti₄Si₃O₁₀ (NaTS) were systemically studied by both experiments and model simulation. Experimental results showed that the curve of crystallinity with time was a characteristic signmoid in the shape that indicated the crystallization of Na₄Ti₄Si₃O₁₀ was a typical spontaneous nucleation process on the laboratory scale. Crystallization of NaTS belongs to the liquid-liquid transformation mechanism and the reaction is endothermic (ΔH = 15.3 kJ/mol). A mathematic model of crystallization kinetics was developed to simulate the synthesis of NaTS. Runge-Kutta and simplex methods were adopted to solve the partial differential equations. Model results fitted well with the experimental data and showed that the synthesis process belongs to spontaneous nucleation and crystal growth. Moreover, the very small crystal growth constant (5.6·10⁻⁷) and gel dissolution constant (7.0·10⁻⁷) indicate they are the rate-limiting steps of the whole synthesis process.     

多柱色谱技术进展

在色谱分析过程中，利用串联、并联或串并联结合的方式将多根色谱柱组合起来，可以实现高通量和高分辨的分离效果。相比于传统单柱色谱技术，多柱技术很好地满足了批量样品分析和复杂生物样品分离分析的需求，因此引起了广泛关注。该文对多柱技术在多维分离、芯片色谱、毛细管电泳、固定相筛选以及串联色谱等领域的应用进行了综述，并对其发展前景进行了展望。     

新型蒈酸基双酰肼化合物的合成及其生物活性

先将3-蒈烯分子中的碳碳双键氧化开环制得蒈酮酸，再将羰基还原成亚甲基得到蒈酸，酰氯化后与系列酰肼发生N-酰化反应合成了14个新型蒈酸基双酰肼化合物(5a～5n)，其结构经UV-Vis、¹H NMR、¹³C NMR、 FT-IR和MS(ESI)表征，并测试了目标化合物的抑菌和除草活性。结果显示：在用药量为50 μg·mL^-1时，目标化合物对花生褐斑病菌、小麦赤霉病菌、黄瓜枯萎病菌、苹果轮纹病菌、番茄早疫病菌、玉米小斑病菌、西瓜炭疽病菌以及水稻纹枯病菌等8种植物病原菌具有一定的抑制活性，其中化合物蒈酸基α-噻吩甲酰肼5f（R=α-thiophene）对苹果轮纹病菌的抑制率达85.0%，优于阳性对照百菌清。在用药量为100 μg·mL^-1时，化合物蒈酸基3′,4′-二甲氧基苯甲酰肼5j(R=3′,4′-OMe-Ph)、蒈酸基-m-甲氧基苯甲酰肼5d(R=m-OMe-Ph)、蒈酸基-m-甲基苯甲酰肼5b(R=m-Me-Ph)和蒈酸基苯甲酰肼5a(R=Ph)对油菜胚根生长的抑制率分别为88.5%、 86.1%、 85.1%和82.6%（均为A级活性水平），优于阳性对照丙炔氟草胺。     

老年人彩度对比敏感度函数研究及滤波应用

为研究老年人彩色视觉频率响应特性，获取彩度对比敏感度与空间频率之间的函数关系，本文在LCH均匀颜色空间基础上，固定明度和色调角值，以彩度作为变量，设计人眼彩度对比敏感度实验，进行人眼视觉观察实验。获得彩度对比敏感度与空间频率的关系，并构建指数型对比敏感度函数模型。经分析表明老年人眼彩度对比敏感度随着空间频率的增加，产生先升高再缓慢降低的变化，各色调角下彩度对比度存在差异。经分析人眼对比敏感度差异与人眼视觉辨色特性有很大的相关性。并且，将构建的对比敏感度函数模型用于实现基于人眼视觉系统的滤波处理。     

Effects of double substitution on the thermodynamic stabilities of nitrogen radicals

Ｓｔｕｄｉｅｓｏｎｋｉｎｅｔｉｃｓｏｆｒａｄｉｃａｌｒｅａｃｔｉｏｎｓ[1]ａｎｄｏｎＣＨｂｏｎｄｄｉｓｓｏｃｉａｔｉｏｎｅｎｅｒｇｉｅｓ(ＢＤＥ)[2]ｈａｖｅｓｈｏｗｎｔｈａｔｃａｒｂｏｎｒａｄｉｃａｌｓａｒｅｓｔａｂｉｌｉｚｅｄｂｙｅｉｔｈｅｒａｎｅｌｅｃｔｒｏｎｄｏｎａｔｉｎｇｇｒｏｕｐ(ＥＤＧ)ｏｒａｎｅｌｅｃｔｒｏｎｗｉｔｈｄｒａｗｉｎｇｇｒｏｕｐ(ＥＷＧ),ａｎｄｔｈａｔｉｆａｃａｒｂｏｎｒａｄｉｃａｌｉｓｓｕｂｓｔｉｔｕｔｅｄｗｉｔｈｂｏｔｈａｎＥＤＧａｎｄａｎＥＷＧａｔｔｈｅｓａｍｅｃｅｎ…     

壳聚糖对鞣酸絮凝作用的研究

以壳聚糖为絮凝剂，采用絮凝法除去中药药液中的杂质。以鞣酸为研究对象，从鞣酸浓度，体系温度，ＰＨ絮凝剂用量粘均分子量等方面探讨其絮凝规律，用正交试验优化其絮凝条件，为实施中药药液的絮凝法精制工艺提供参考。