Template synthesis

模板合成
  • 文章类型: Journal Article
    中性Pd24-立方笼的合成及客体识别性能,报道了[{Pd3(NiPr)3PO}8(μ2-Cl)24]1。立方体组装体的形成通过由肟基接头指导的独占一锅法配体辅助途径进行。肟基配体的初始配位将[Pd3(NiPr)3PO]3多面体构建单元预先组织为四聚体中间体,然后在存在氯离子的情况下转化为氧酰亚胺系链的四面体组装体,并转化为立方体笼1。在不存在定向肟基接头的情况下,没有观察到笼子的形成,发现Pd6前体发生自缩合,产生了一个新的五聚体多面体簇,[Pd5{(NiPr)3PO}2(OAc)2(OH)2]2。立方体的中心腔已被探测用于客体封装研究,显示与酚类客体分子的高结合,缔合常数约为104-105M-1。主体-客体配合物的有利形成归因于主体和客体官能团之间的强氢键相互作用。
    The synthesis and guest recognition properties of a neutral Pd24-cubic cage, [{Pd3(NiPr)3PO}8(μ2-Cl)24] 1 are reported. The formation of the cubical assembly takes place by an exclusive one-pot ligand-assisted pathway directed by an oximido linker. The initial coordination of the oximido ligand pre-organizes the [Pd3(NiPr)3PO]3+ polyhedral building units into a tetrameric intermediate, which then transforms into an oximido-tethered tetrahedral assembly and to the cubical cage 1 in the presence of chloride ions. In the absence of the directing oximido linker, no cage formation was observed, and the Pd6-precursor was found to undergo self-condensation, giving rise to a new pentameric polyhedral cluster, [Pd5{(NiPr)3PO}2(OAc)2(OH)2] 2. The central cavity of the cube has been probed for guest encapsulation studies, which shows a high binding with phenolic guest molecules with association constants of the order of 104-105 M-1. The favorable formation of host-guest complexes was attributed to the strong hydrogen bonding interactions between the host and guest functional groups.
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  • 文章类型: Journal Article
    通过模板策略制备了具有独特形态特征和高表面积的多孔α-Fe2O3空心棒/还原氧化石墨烯(α-Fe2O3HR/RGO)复合材料,对其进行了系统研究,发现其具有出色的超电容性能。当在三电极设置中用作活性材料时,优化的α-Fe2O3HR/RGO-30,包含76.5wt%的α-Fe2O3和23.2wt%的RGO,能够提供426.3Fg-1的最大比电容,出色的倍率性能以及令人满意的循环寿命,在10Ag-1下连续充电/放电超过10,000次循环后,电容保持率为87.7%,库仑效率为98.9%。α-Fe2O3HR/RGO-30电极的这种电化学行为可以与以前文献中记载的许多Fe2O3基电极的电化学行为相媲美甚至超越。稍后,制备了α-Fe2O3HR/RGO-30//α-Fe2O3HR/RGO-30的对称超级电容器电池。组装的设备提供了18.7Whkg-1的最大能量密度,并且还表现出了值得称道的速率能力,并具有稳定的循环耐久性(在5Ag-1下进行10,000次循环充电/放电后,电容保留率为83.2%,库仑效率为99.3%)。这些显著的电化学性能使α-Fe2O3HR/RGO-30复合材料成为先进储能系统的高电位材料。
    Porous α-Fe2O3 hollow rods/reduced graphene oxide (α-Fe2O3 HR/RGO) composites with unique morphological characteristics and a high surface area are prepared through a template strategy, which was systematically studied and found to have outstanding supercapacitive properties. When served as active material in a three-electrode setup, the optimized α-Fe2O3 HR/RGO-30, comprised 76.5 wt% α-Fe2O3 and 23.2 wt% RGO, was able to offer the largest specific capacitance of 426.3 F g-1, an excellent rate capability as well as satisfactory cycle life with capacitance retention of 87.7% and Coulombic efficiency of 98.9% after continuously charging/discharging at 10 A g-1 for beyond 10,000 cycles. Such electrochemical behaviors of the α-Fe2O3 HR/RGO-30 electrode can rival or even surpass those of many Fe2O3-based electrodes documented in the previous literature. Later, a symmetric supercapacitor cell of α-Fe2O3 HR/RGO-30//α-Fe2O3 HR/RGO-30 was fabricated. The assembled device offers the maximum energy density of 18.7 Wh kg-1, and also exhibits commendable rate capability, and features stable cycling durability (with capacitance retention of 83.2% together with a Coulombic efficiency of 99.3% after 10,000-cycle charge/discharge at 5 A g-1). These notable electrochemical performances enable the α-Fe2O3 HR/RGO-30 composite to be a high-potential material for advanced energy storage systems.
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  • 文章类型: Journal Article
    基于锰的造影剂(MnCA)已经作为基于钆的造影剂(GdCA)的合适替代物出现。然而,由于它们的动力学不稳定性和费力的合成程序,只有少数MnCA发现了临床MRI应用。在这项工作中,我们采用了高度创新的单罐模板合成策略来开发MnCA,MnLMe,并研究了体外最重要的理化性质。MnLMe在中等(20和64MHz)和高磁场(300和400MHz)下都显示出优化的r1弛豫率,并且增强的r1b=21.1mM-1s-1(20MHz,298K,pH7.4)与BSA结合后(Ka=4.2×103M-1)。体内研究表明,MnLMe通过肾脏排泄完整地清除到膀胱中,与市售的GdCAMagnevist相比,具有延长的血液半衰期。MnLMe作为新型MRI造影剂显示出巨大的希望。
    我们提出了一种基于锰的MRI造影剂的单锅模板合成策略,MnLMe.MnLMe对锌金属转移具有高度惰性,并在与血清白蛋白非共价相互作用时显示出增强的T1弛豫性。体内研究显示,与市售造影剂Magnevist相比,肝脏的对比度增强更高,血液半衰期更长。MnLMe显示出用作血池剂的巨大潜力。
    Manganese-based contrast agents (MnCAs) have emerged as suitable alternatives to gadolinium-based contrast agents (GdCAs). However, due to their kinetic lability and laborious synthetic procedures, only a few MnCAs have found clinical MRI application. In this work, we have employed a highly innovative single-pot template synthetic strategy to develop a MnCA, MnLMe, and studied the most important physicochemical properties in vitro. MnLMe displays optimized r 1 relaxivities at both medium (20 and 64 MHz) and high magnetic fields (300 and 400 MHz) and an enhanced r 1 b=21.1 mM-1 s-1 (20 MHz, 298 K, pH 7.4) upon binding to BSA (K a=4.2×103 M-1). In vivo studies show that MnLMe is cleared intact into the bladder through renal excretion and has a prolonged blood half-life compared to the commercial GdCA Magnevist. MnLMe shows great promise as a novel MRI contrast agent.
    We present a single‐pot template synthesis strategy for a manganese‐based MRI contrast agent, MnLMe. MnLMe is highly inert toward zinc‐transmetallation and displays enhanced T 1 relaxivity upon non‐covalent interaction with serum albumin. In vivo studies show higher contrast enhancement in the liver and longer blood half‐life than that of the commercially available contrast agent Magnevist. MnLMe shows great potential for use as a blood pool agent.
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  • 文章类型: Journal Article
    在活性位点含有3d金属高价离子的摩尔水氧化催化剂的合成可用性是实现大规模光和电化学水分解的先决条件。在这里,二铵{μ-1,3,4,7,8,10,12,13,16,17,19,22-十二-氮杂-四环-[8.8.4.13,17.18,12]四-椰草烷-5,6,14,15,20,21-六-奥托}高铁酸盐(IV)乙酸三-醇酸盐的合成和晶体结构,据报道,(NH4)2[FeIV(C12H12N12O6)]·3CH3COOH或(NH4)2[FeIV(L-6H)]·3CH3COOH。FeIV离子被大多环配体包封,可以描述为十二碳氮杂四环笼,具有两个封端三氮杂环己烷片段,形成三个五元和六个六元交替螯合环,并带有中心FeIV离子。FeIV的局部配位环境由六个去质子化的酰肼硝基原子形成,稳定不寻常的氧化状态。FeIV离子位于空间群C2/c的双重旋转轴(多重性4,Wyckoff字母e)上。其协调几何形状介于三角棱镜(畸变角φ=0°)和反棱镜(φ=60°)之间,φ=31.1°。Fe-N键的长度在1.9376(13)-1.9617(13)的范围内,正如预期的四价铁。结构分析表明,每个铁(IV)配合物另外共结晶三个乙酸分子,其中一个在四个位置上位置混乱。在晶体结构中,铵阳离子,复杂的二阴离子和乙酸摩尔离子通过复杂的氢键系统相互连接,主要通过作为受体的草酰胺氧原子。
    The synthetic availability of mol-ecular water oxidation catalysts containing high-valent ions of 3d metals in the active site is a prerequisite to enabling photo- and electrochemical water splitting on a large scale. Herein, the synthesis and crystal structure of di-ammonium {μ-1,3,4,7,8,10,12,13,16,17,19,22-dodeca-aza-tetra-cyclo-[8.8.4.13,17.18,12]tetra-cosane-5,6,14,15,20,21-hexa-onato}ferrate(IV) acetic acid tris-olvate, (NH4)2[FeIV(C12H12N12O6)]·3CH3COOH or (NH4)2[FeIV(L-6H)]·3CH3COOH is reported. The FeIV ion is encapsulated by the macropolycyclic ligand, which can be described as a dodeca-aza-quadricyclic cage with two capping tri-aza-cyclo-hexane fragments making three five- and six six-membered alternating chelate rings with the central FeIV ion. The local coord-ination environment of FeIV is formed by six deprotonated hydrazide nitro-gen atoms, which stabilize the unusual oxidation state. The FeIV ion lies on a twofold rotation axis (multiplicity 4, Wyckoff letter e) of the space group C2/c. Its coordination geometry is inter-mediate between a trigonal prism (distortion angle φ = 0°) and an anti-prism (φ = 60°) with φ = 31.1°. The Fe-N bond lengths lie in the range 1.9376 (13)-1.9617 (13) Å, as expected for tetra-valent iron. Structure analysis revealed that three acetic acid mol-ecules additionally co-crystallize per one iron(IV) complex, and one of them is positionally disordered over four positions. In the crystal structure, the ammonium cations, complex dianions and acetic acid mol-ecules are inter-connected by an intricate system of hydrogen bonds, mainly via the oxamide oxygen atoms acting as acceptors.
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  • 文章类型: Journal Article
    超分子模板在原子精确的杂金属阵列排列中的应用对于追求功能材料是重要的。在这里,我们报告说,双层超分子三去质子化的三聚氰胺二聚体在杂金属金(I)-银(I)大环簇[μ6-(C3N6H3)3-]2-AuI6AgI6的构建中起有效的模板作用。X射线单晶结构分析表明,冠状AuI6AgI6大环围绕两个平行堆叠的μ6-(C3N6H3)3-部分排列,并以π-π相互作用保持在一起。理论计算表明,[μ6-(C3N6H3)3-]2基序主要有助于电子结构中的近占据轨道,这与其发光特性密切相关。这项工作表明,包含多个对称结合位点的超分子模板可能是构建功能性金属簇的简便方法。
    The application of supramolecular templates in aligning atomically precise heterometal arrays is important for pursuing functional materials. Herein, we report that a bilayered supramolecular tri-deprotonated melamine dimer functions as an effective template in the construction of a heterometallic gold(I)-silver(I) macrocyclic cluster [μ6 -(C3 N6 H3 )3- ]2 -AuI 6 AgI 6 . X-ray single crystal structural analysis showed that a crown-like AuI 6 AgI 6 macrocycle is aligned around two parallelly stacked μ6 -(C3 N6 H3 )3- moieties hold together with π-π interactions. Theoretical calculations revealed that the [μ6 -(C3 N6 H3 )3- ]2 motif dominantly contributes to the near-occupied orbitals in the electronic structure, which is closely related to its luminescence properties. This work demonstrates that the supramolecular templates containing multiple symmetric binding sites may present a facile approach in the construction of functional metal clusters.
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  • 文章类型: Journal Article
    目的:最近报道无表面活性剂的微乳液(SFME)是自由基聚合的有趣介质。这项研究的目的是研究PMMA单体聚合物以及PMMA-PHEMA共聚物的形态与聚合前SFME的预期性质之间的联系。研究了具有非离子表面活性剂的基于表面活性剂的微乳液作为参考体系。预计SFME的介观结构(水包油状,双连续,反)对应于后者的聚合物形态,就像基于表面活性剂的系统一样。
    方法:由水组成的简单SFME系统,水溶助长剂(异丙醇或叔丁醇),和甲基丙烯酸甲酯(MMA)作为可聚合油以及包含甲基丙烯酸2-羟乙酯(HEMA)作为额外的两亲性共聚单体的更复杂的系统,被调查了。使用Tergitol15-S-12和SynperonicA11-LQ-(TH)的混合物作为表面活性剂的基于表面活性剂的系统,水,和MMA在存在和不存在HEMA作为可聚合助表面活性剂的情况下作为参考系统进行了研究。通过记录(伪)三元相图进行结构分析,动态光散射(DLS),和电导率测量。使用油溶性引发剂PEROXANBCC在318K下进行24小时的聚合,并进行邻近的冻干。通过光学显微镜确定干燥聚合物的形态,扫描电子显微镜,和BET吸附等温线。
    结果:可以从以前的介观结构中获得尺寸范围为200nm至一些µm的不同形态的多孔聚合物(从液滴状聚集体的凝结物到海绵状聚集体),无表面活性剂的混合物。以前是非结构化的,富油地区导致固体,没有纳米结构形态的透明聚合物。基于表面活性剂的参考体系包含与可比较的不含表面活性剂的体系在聚合之前非常相似的相行为和相似的聚合物形态。这导致假设HEMA的水溶助长行为及其与MMA和水的相互作用是该系统中的结构赋予因素。
    OBJECTIVE: Surfactant-free microemulsions (SFMEs) were recently reported to be an interesting medium for free-radical polymerizations. The aim of this study is to investigate the link between the morphology of PMMA monopolymers as well as PMMA-PHEMA-copolymers with the expected nature of the SFME before polymerization. A surfactant-based microemulsion with nonionic surfactants was investigated as a reference system. It is expected that the kind of mesostructuring of the SFME (oil-in-water-like, bicontinuous, inverse) corresponds with the latter polymer morphology, just like it is the case in surfactant-based systems.
    METHODS: Simple SFME systems composed of water, a hydrotrope (isopropanol or tert-butyl alcohol), and methyl methacrylate (MMA) as polymerizable oil as well as the more complex system comprising 2-hydroxyethyl methacrylate (HEMA) as an additional amphiphilic co-monomer, were investigated. A surfactant-based system using a mixture of Tergitol 15-S-12 and Synperonic A11-LQ-(TH) as surfactants, water, and MMA in the presence and absence of HEMA as polymerizable co-surfactant was investigated as a reference system. Structural analysis was done by recording (pseudo-)ternary phase diagrams, dynamic light scattering (DLS), and conductivity measurements. Polymerizations were performed using the oil-soluble initiator PEROXAN BCC at 318 K for 24 h with adjacent lyophilization. The morphology of dried polymers was determined by light microscopy, scanning electron microscopy, and BET adsorption isotherms.
    RESULTS: Porous polymers of different morphologies (from coagulations of droplet-like aggregates to sponge-like ones) in the size range of 200 nm up to some µm can be derived from previously mesostructured, surfactant-free mixtures. Previously unstructured, oil-rich regions lead to solid, transparent polymers without nanostructured morphologies. The surfactant-based reference system comprises remarkably similar phase behavior before polymerizations and similar polymer morphologies as the comparable surfactant-free system. This leads to the assumption that the hydrotropic behavior of HEMA and its interplay with MMA and water is the structure-giving factor in this system.
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  • 文章类型: Journal Article
    这项研究提出了一种使用聚合物材料制造基于薄膜的加热元件的方法,该聚合物材料具有嵌入其中的交叉导电元件阵列。使用厚度为12μm的径迹蚀刻膜(TM)作为模板,它们的毛孔充满了金属,形成一个三维网格。由于TM独特的制造工艺,里面的毛孔相互交叉,当填充有金属时,允许单独的纳米线(NW)之间的接触。实验结果表明,用银填充TM孔允许加热温度高达60度,而不会变形或损坏加热元件。所得的柔性加热元件可用于医疗装置中用于加热目的或作为热障涂层。
    This study presents a method for fabricating a film-based heating element using a polymer material with an array of intersecting conductive elements embedded within it. Track-etched membranes (TM) with a thickness of 10μm were used as the template, and their pores were filled with metal, forming a three-dimensional grid. Due to the unique manufacturing process of TM, the pores inside intersect with each other, allowing for contacts between individual nanowires (NWs) when filled with metal. Experimental results demonstrated that filling the TM pores with silver allows for heating temperatures up to 78 degrees without deformation or damage to the heating element. The resulting flexible heating element can be utilized in medical devices for heating purposes or as a thermal barrier coating.
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  • 文章类型: Journal Article
    在koneramine(LROR\')的骨架中存在的脆弱的半缩醛胺醚键,三齿配体,在立体选择性自组装的sn-[Cu(LROR')X2]配合物中与铜(II)结合,通过后期阶段的配体修饰将其转化为坚固的亚甲基键,以形成相应的消旋-[Cu(LRH)Cl2]配合物。保留配位球。通过利用许多金属离子,可以显示出koneramine配合物的立体选择性自组装的普遍性,阴离子,胺,具有完整特征的醇和硫醇。
    Fragile hemiaminal ether linkages present in the backbone of koneramines (LR OR\'), tridentate ligands, bound to copper(II) in stereoselectively self-assembled syn-[Cu(LR OR\')X2 ] complexes were transformed into sturdy methylene linkages to make corresponding rac-[Cu(LR H)Cl2 ] complexes by late-stage ligand modification after coordination with the retention of coordination sphere. The generality of stereoselective self-assembly of koneramine complexes is shown by utilising a number of metal ions, anions, amines, alcohols and thiols with complete characterisations.
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  • 文章类型: Journal Article
    在目前的工作中,制备了一种掺入钼酸钴(CoMoO4)空心球的石墨氮化碳(g-CN)复合材料,用于电化学检测二甲硝唑(DZ)。中空结构的CoMoO4和g-CN纳米片之间的协同效应促进了电子通过动力学势垒的传输,从而提供具有增加的电活性部位的高电导率。拟议的CoMoO4@g-CN修饰电极显示出较宽的线性范围(0.001-492.77μM)和较低的检测限(LOD:0.4nM),用于通过安培法(i-t)法测定DZ。此外,CoMoO4@g-CN修饰电极具有良好的工作稳定性,抗干扰能力(共干扰化合物过量五倍)和重现性。这些结果表明,CoMoO4@g-CN修饰的玻碳电极(GCE)对食品样品中DZ的检测具有令人满意的回收率。
    In the present work, a cobalt molybdate (CoMoO4) hollow spheres-incorporated graphitic carbon nitride (g-CN) composite is prepared for the electrochemical detection of dimetridazole (DZ). The synergistic effect between the hollow-structured CoMoO4 and g-CN nanosheets facilitates the transportation of electrons through kinetic barriers, thereby providing a high electrical conductivity with increased electroactive sites. The proposed CoMoO4@g-CN-modified electrode displayed a wide linear range (0.001-492.77 μM) and a lower detection limit (LOD: 0.4 nM) for the determination of DZ through the amperometry (i-t) method. In addition, the CoMoO4@g-CN-modified electrode achieved good operational stability, anti-interfering ability (five-fold excess amount of co-interfering compounds) and reproducibility. These results demonstrate the increased electrocatalytic activity of CoMoO4@g-CN modified glassy carbon electrode (GCE) towards the detection of DZ in food samples with satisfactory recovery ranges.
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  • 文章类型: Journal Article
    具有高纵横比的纳米结构材料因其独特的性能而被广泛研究。特别是,纳米片具有安全性,分散性,和纳米效应,和纳米片具有非常小的厚度表现出独特的性能。对于不可剥落的材料,已经研究了使用各种界面作为模板的自下而上的纳米片生长。这篇综述文章介绍了纳米片在界面和分层结构的合成;它解释了每种界面类型的特征,其优势,和它的独特性。界面用作纳米片合成的模板。我们可以很容易地使用液-液和气-液界面作为模板;然而,纳米片的厚度通常变厚,因为它允许材料的厚度增长。固体-气体和固体-液体界面可以防止纳米片的厚度增长。然而,在合成后需要除去模板固体。各种材料的分层结构在层之间提供二维反应场。这些方法具有很高的通用性,通过这些方法合成的纳米片很薄。最后,这篇综述探讨了与工业化生产可扩展纳米片合成方法相关的关键挑战和机遇。
    Nanostructured materials with high aspect ratios have been widely studied for their unique properties. In particular, nanosheets have safety, dispersibility, and nanosized effects, and nanosheets with exceptionally small thicknesses exhibit unique properties. For non-exfoliable materials, the bottom-up nanosheet growth using various interfaces as templates have been investigated. This review article presents the synthesis of nanosheets at the interfaces and layered structure; it explains the features of each interface type, its advantages, and its uniqueness. The interfaces work as templates for nanosheet synthesis. We can easily use the liquid-liquid and gas-liquid interfaces as the templates; however, the thickness of nanosheets usually becomes thick because it allows materials to grow in thickness. The solid-gas and solid-liquid interfaces can prevent nanosheets from growing in thickness. However, the removal of template solids is required after the synthesis. The layered structures of various materials provide two-dimensional reaction fields between the layers. These methods have high versatility, and the nanosheets synthesized by these methods are thin. Finally, this review examines the key challenges and opportunities associated with scalable nanosheet synthesis methods for industrial production.
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