Highly Efficient,Tripodal Ion-Pair Receptors for Switching Selectivity between Acetates and Sulfates Using Solid–Liquid and Liquid–Liquid Extractions

A tripodal, squaramide-based ion-pair receptor 1 was synthesized in a modular fashion, and ¹H NMR and UV-vis studies revealed its ability to interact more efficiently with anions with the assistance of cations. The reference tripodal anion receptor 2, lacking a crown ether unit, was found to lose the enhancement in anion binding induced by presence of cations. Besides the ability to bind anions in enhanced manner by the “single armed” ion-pair receptor 3, the lack of multiple and prearranged binding sites resulted in its much lower affinity towards anions than in the case of tripodal receptors. Unlike with receptors 2 or 3, the high affinity of 1 towards salts opens up the possibility of extracting extremely hydrophilic sulfate anions from aqueous to organic phase. The disparity in receptor 1 binding modes towards monovalent anions and divalent sulfates assures its selectivity towards sulfates over other lipophilic salts upon liquid–liquid extraction (LLE) and enables the Hofmeister bias to be overcome. By changing the extraction conditions from LLE to SLE (solid–liquid extraction), a switch of selectivity from sulfates to acetates was achieved. X-ray measurements support the ability of anion binding by cooperation of the arms of receptor 1 together with simultaneous binding of cations.     

Pillarquinones and Pillararenequinones

Pillar[n]quinones and pillar[n-m]arene[m]quinones are oxidation products of pillar[n]arenes. Their molecular structure resembles the parent compounds. However, their map of electron density is different. Each 1,4-benzoquinone ring, which replaces a 1,4-dialkoxy-substituted benzene ring decreases the electron density in the interior cavity and increases the electron density on the upper and lower rim of the pillar. The electron donor character is stepwise transformed to an electron acceptor status. This effect alters the complexation tendencies, which are the most interesting properties of these macrocyclic host systems.     

两种结构简单绕丹宁衍生物的合成及其对氟离子的选择性识别研究

设计合成了两个结构简单的绕丹宁衍生物,在CH_2Cl_2-DMSO混合溶剂中利用紫外-可见吸收光谱研究了其与多种阴离子的相互作用,发现它们的吸收光谱对氟离子呈现特异性变化,吸收滴定实验确认它们与氟离子间相互作用的化学计量比为1:1,~1H NMR进一步证实它们与氟离子的作用类型为氢键或脱质子作用。     

Binding Methylarginines and Methyllysines as Free Amino Acids: A Comparative Study of Multiple Host Classes**

Methylated free amino acids are an important class of targets for host-guest chemistry that have recognition properties distinct from those of methylated peptides and proteins. We present comparative binding studies for three different host classes that are each studied with multiple methylated arginines and lysines to determine fundamental structure-function relationships. The hosts studied are all anionic and include three calixarenes, two acyclic cucurbiturils, and two other cleft-like hosts, a clip and a tweezer. We determined the binding association constants for a panel of methylated amino acids using indicator displacement assays. The acyclic cucurbiturils display stronger binding to the methylated amino acids, and some unique patterns of selectivity. The two other cleft-like hosts follow two different trends, shallow host (clip) following similar trends to the calixarenes, and the other more closed host (tweezer) binding certain less-methylated amino acids stronger than their methylated counterparts. Molecular modelling sheds some light on the different preferences of the various hosts. The results identify hosts with new selectivities and with affinities in a range that could be useful for biomedical applications. The overall selectivity patterns are explained by a common framework that considers the geometry, depth of binding pockets, and functional group participation across all host classes.     

负离子聚氨酯合成革的研制

医学研究已经证明，负离子产品对人体健康有保健作用。本工作选用奇冰石超细粉末作为无机填料添加到聚氨酯树脂中制成负离子合成革，讨论了粉末最佳混入比例，并与普通合成革进行了比较。结果表明，混入奇冰石粉末的聚氨酯合成革可持续释放较高浓度的空气负离子，对人体健康产生有益的作用。     

一种新的氨基硫脲类阴离子受体的合成及其性质研究

合成了一种新的阴离子受体化合物PySN,通过1H NMR对其进行了表征。受体分子结合不同阴离子的紫外-可见光谱和荧光发射光谱变化表明:在非质子性溶剂中,PySN可选择性识别和传感氟离子、醋酸根及磷酸二氢根离子。     

负离子抗菌复合陶瓷研究

通过将电气石直接加入陶瓷坯体中,将载银抗菌剂和TiO2通过浸渍复合在坯体表面及坯体通孔表面,制成了负离子抗菌复合陶瓷产品,并分析了该陶瓷的配方、烧结温度和浸泡时间对负离子释放量和抗菌性能的影响,以及利用X射线衍射对该种陶瓷的微观结构进行了研究.     

新型阴离子孪连表面活性剂的合成

系列长链环氧烷与不同短链二醇在75~80℃、NaH作用下合成了系列中间体孪连长链二醇,此中间体再与1,3-丙烷磺酸内酯在THF、NaH中反应得到了疏水链长度和连接基长度不同的7种磺酸盐孪连表面活性剂。核磁共振氢谱及红外光谱的结构分析证实了它们的结构。它们的表面张力为26.5~34 mN/m,临界胶束浓度为0.001~0.01 mmol/L,结果表明,它们的表面活性比相应碳链的常规表面活性剂强很多。疏水链长度和连接基长度的增长,有助于表面活性的提高。     

萘甲酰腙类阴离子受体的合成及识别研究

合成了用于识别阴离子的主体分子——2，4-二羟基苯乙酮缩-2-萘甲酰腙（X），通过红外光谱、核磁共振谱和质谱表征其结构；研究了阴离子对X吸收光谱的影响。实验表明：在乙腈中，阴离子加入对X的吸收光谱影响大小为：F^-〉H2PO4^-〉AcO^-，而cl^-、Br^-、I^-和HSO4^-对X的吸收光谱几乎没影响。Job法实验得出X与F的结合比为1：1。     

阴离子交换树脂交换容量测定

对强碱性阴离子交换树脂交换容量的测定方法进行了改进、简便易行。     

珍珠负离子复合功能涤纶的制备及其性能

将珍珠改性涤纶母粒与负离子母粒均匀混合后,通过熔融纺丝的方法制备出复合功能纤维,对其进行了灰分测试,并依据GB/T 5009—2003分析了纤维中氨基酸成分,结果显示:珍珠负离子改性涤纶中所含氨基酸种类多达18种,其中对纤维性能影响最为重要的酪氨酸质量分数为0.0012%。在室温条件下,使用空气负离子测试仪测试了复合功能纤维的负离子释放量及远红外线发射率,结果显示:该纤维负离子释放量最大值可达到6000个/cm3,远红外线发射率F(8¹4μm)>0.88。使用扫描电子显微镜观察了珍珠改性涤纶的微观结构,可见超细珍珠粒子较均匀地分布在纤维表面,并与纤维有着紧密的结合。     

强碱阴树脂硅污染的复苏

某除盐水处理系统强碱阴树脂被硅污染后,出水水质下降、周期制水量减少。为复苏被污染的强碱阴树脂,保证系统供水水质,采用了“再生碱液用量加倍、浓稀结合、多次再生”的方法对污染树脂进行了处理,最终污染树脂得到复苏,系统产水水质合格。实践证明该处理方法切实有效,结合实践分析研究了强碱阴树脂被硅污染的机理,提出了复苏方法和预防措施。     

Plasminogen Receptors and Fibrinolysis

The ability of cells to promote plasminogen activation on their surfaces is now well recognized, and several distinct cell surface proteins have been demonstrated to function as plasminogen receptors. Here, we review studies demonstrating that plasminogen bound to cells, in addition to plasminogen directly bound to fibrin, plays a major role in regulating fibrin surveillance. We focus on the ability of specific plasminogen receptors on eukaryotic cells to promote fibrinolysis in the in vivo setting by reviewing data obtained predominantly in murine models. Roles for distinct plasminogen receptors in fibrin surveillance in intravascular fibrinolysis, immune cell recruitment in the inflammatory response, wound healing, and lactational development are discussed.     

阴离子型聚电解质盐溶液性质的研究进展

阴离子型聚电解质在极性溶剂中会发生电离,导致大分子链上带有大量的净负电荷。它在盐溶液中会与一些反离子,特剐是多价金属阳离子等发生作用,从而使大分子形态发生改变,光学性质,电化学性质随之发生变化,作用强烈时,可发生沉淀。     

Taste Receptors beyond Taste Buds

Taste receptors are responsible for detecting their ligands not only in taste receptor cells (TRCs) but also in non-gustatory organs. For several decades, many research groups have accumulated evidence for such “ectopic” expression of taste receptors. More recently, some of the physiologic functions (apart from taste) of these ectopic taste receptors have been identified. Here, we summarize our current understanding of these ectopic taste receptors across multiple organs. With a particular focus on the specialized epithelial cells called tuft cells, which are now considered siblings of type II TRCs, we divide the ectopic expression of taste receptors into two categories: taste receptors in TRC-like cells outside taste buds and taste receptors with surprising ectopic expression in completely different cell types.     

控制甲铵冷凝器氯离子腐蚀的电化学方法

二氧化碳汽提法尿素装置高压甲铵冷凝器在壳程水侧，由于氯离子在上下管板缝隙内的富集，而导致３１６Ｌ不锈钢管束产生应力腐蚀ＳＣＣ破裂，是长期影响大型尿素装置安稳长满优生产和设备服役寿命最重要的原因之一。本文提出一种全新的电化学腐蚀控制方法使得人们有可能在不改变设备工艺参数和设备结构，不花许多钱，不费许多时间的前提下，从根本上控制这种应力腐蚀破裂的发生与发展。     

A novel electroneutral anion host based on organoboron betaines

Host-guest binding of anions in organic solvents may find attractive applications in ion sensing and transport, if the host can extract the negatively charged guest species from its solvation sphere. The most powerful means to dismantle the anionic guest from solvent molecules that is required for selective binding is to provide positive charges in the host compound. They have to be counterbalanced by negatively charged subsites in order to conserve electroneutrality, but must avoid collapse into ion pairing with the cationic sites. According to this concept the cage compound 3 was constructed by attachment of anionic tetraphenylborate moieties to the parent macrotricyclic amine 1 . The betainic product 3 was shown to be soluble in water-immiscible dipolar organic solvents like propylene carbonate and formed inclusion complexes with chloride and bromide in the gas phase as well as in solution.     

阴离子交换树脂在精制盐酸生产中的应用

介绍了树脂法去除工业盐酸中铁及重金属离子的新工艺,讨论了阴离子交换树脂的工业盐到中除铁的工艺及参数。     

负离子添加剂在硅橡胶中的应用研究

文中报告了在我国东北嫩江流域发现的一种新型天然纳米级材料,探讨了嫩江蛋白石页岩的结构改性及释放负离子的机理,它可以和其他矿物一起配制成负离子添加剂。利用气流法制备了平均粒径为0．47μm的奇才系列释放负离子超微细粉体材料。通过掺合,采用一般橡胶加工工艺。试制了释放负离子的硅橡胶,其释放负离子数达到了2000个／cm^3以上,达到了维持人体健康的基本需求。