Termansenpearson3641

Over the past few decades, the field has evolved from the addition of carbon electrophiles in a manner similar to that of protonation reactions to more organometallic-inspired reactivity, including insertions, 1,2-additions, and cycloadditions. Various N-C, N-Si, and N-B bond-forming reactions have been discovered, highlighting that the challenge for catalytic chemistry is not in the reactivity of coordinated dinitrogen but rather removal of the functionalized ligand from the coordination sphere of the metal.Tuning crystal phase transformations is very important for obtaining polymorphs for phosphors with the ideal optical properties and stability. Mn4+-doped K2GeF6 (KGF) is a typical polymorphic phosphor, but the thermodynamic and kinetic mechanism of its phase transformation is still unclear. Herein, the phase transformation of polymorphs varying from P63mc KGF and trigonal KGF to P63mc Si4+-doped KGF is realized by introducing the synergistic action of an HF solution and Si4+ ions. The full structural refinements of KGF polymorphs at room temperature and the electronic band structure calculations were performed. The results show that the Si4+-doped hexagonal KGF polymorph with good photoluminescence properties is the most stable phase according to the calculated total energy landscape and relative formation energy. The morphologic changes were monitored in situ to clearly understand the rapid phase transformation mechanism, which proves that the phase transformation is driven by a simple precipitation-dissolution equilibrium and ionic exchange.In this work, a simple electrochemiluminescence (ECL) imaging method based on the cell shield of the ECL emission was developed for the morphological and quantitative analysis of living cells under external stimulation. ECL images of MCF-7 cells cultured on or captured at the glassy carbon electrode (GCE) surface in a solution of tris(2,2'-bipyridyl)ruthenium(II)-tri-n-propylamine were recorded. Important morphological characteristics of living cells, including cell shape, cell area, average cell boundary, and junction distance between two adjacent cells, were directly obtained using the developed negative ECL imaging method. The ECL images revealed gradual morphological changes in cells on the GCE surface. During the course of H2O2 stimulation of cells on the GCE surface, cells shrunk, rounded up, disengaged from surrounding cells, and finally detached from the electrode surface. During the course of electrical stimulation (0.8 V), the cells on the GCE surface exhibited aggregation as demonstrated by increases in the average cell boundary and decreases in the junction distance between two adjacent cells. Additionally, a quantitative method for the sensitive determination of MCF-7 cells with a limit of detection of 29 cells/mL was developed using the negative ECL imaging strategy. This work demonstrates that the proposed negative ECL imaging strategy is a promising approach to assess important morphological characteristics of living cells during the course of external stimulation and to obtain quantitative information on cell concentrations in solution.Ionic conductors are normally prepared from water-based materials in the solid form and feature a combination of intrinsic transparency and stretchability. The sensitivity toward humidity inevitably leads to dehydration or deliquescence issues, which will limit the long-term use of ionic conductors. read more Here, a novel ionic conductor based on natural bacterial cellulose (BC) and polymerizable deep eutectic solvents (PDESs) is developed for addressing the abovementioned drawbacks. The superstrong three-dimensional nanofiber network and strong interfacial interaction endow the BC-PDES ionic conductor with significantly enhanced mechanical properties (tensile strength of 8 × 105 Pa and compressive strength of 6.68 × 106 Pa). Furthermore, compared to deliquescent PDESs, BC-PDES composites showed obvious mechanical stability, which maintain good mechanical properties even when exposed to high humidity for 120 days. These materials were demonstrated to possess multiple sensitivity to external stimulus, such as strain, pressure, bend, and temperature. Thus, they can easily serve as supersensitive sensors to recognize physical activity of humans such as limb movements, throat vibrations, and handwriting. Moreover, the BC-PDES ionic conductors can be used in flexible, patterned electroluminescent devices. This work provides an efficient strategy for making cellulose-based sustainable and functional ionic conductors which have broad application in artificial flexible electronics and other products.A new selenite-sulfate compound Co3(SeO3)(SO4)(OH)2 was prepared using a typical hydrothermal reaction. This compound is found to crystallize in an orthorhombic space group of Pnma, featuring a 2D distorted kagomé structure composed of linear and zigzag Co-chains, in which the magnetic ions construct different isosceles-triangles. Our results of magnetic and specific heat measurements confirm a canted antiferromagnetic order at TN ∼ 29 K. Further, the successive field-induced metamagnetic transitions can be observed at Hc1 ∼ 1 T, Hc2 ∼ 23 T, and Hc3 ∼ 27 T, respectively. A clear magnetic hysteresis loop with a coercive field (Hc) of ∼1.4 T is also observed.Aggregation-induced electrochemiluminescence (AIECL) of the dichlorobis(1,10-phenanthroline)ruthenium(II) (Ru(phen)2Cl2)/tri-n-propylamine (TPrA) system was systematically investigated in H2O-MeCN media. Up to a 120-fold increase in the ECL intensity was observed when the H2O fraction (v%) was changed from 30% to 70%, whereas only an approximately 5.7-fold increase in the corresponding aggregation-induced fluorescence emission was demonstrated. The gradual formation of clusters of Ru(phen)2Cl2 nanoaggregates along with the increase in the H2O fraction to MeCN, which was verified by dynamic light scattering (DLS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM), was believed to be responsible for the remarkable ECL enhancement. Significantly, the above-mentioned AIECL behavior was found to be very sensitive to the types and sequences of nucleic acids present in solution, which provided an effective and novel strategy for distinguishing RNA from DNA and for differentiating different miRNAs.