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排序方式: 共有1333条查询结果,搜索用时 15 毫秒
1.
Adel Z. El‐Sonbati Mostafa A. Diab Ahmed M. Eldesoky Shaimaa M. Morgan Omnia L. Salem 《应用有机金属化学》2019,33(5)
Novel polymer complexes of 8‐hydroxyquinoline‐5‐sulfonic acid hydrate ( H 2 L ) with Cu2+, Co2+ and Ni2+ chloride were prepared and characterized. Microanalysis, magnetic susceptibility, IR spectra, electron spin resonance, mass spectra, X‐ray, molar conductance, thermal, and UV–Vis spectra studies have been used to confirm the structure of the prepared polymer complexes. The molecular and electronic structures of the hydrogen bond conformers for ligand ( H 2 L ) were optimized theoretically and the quantum chemical parameters were calculated. On the basis of elemental and IR data, the chemical structure of metal chelates commensurate that the tri‐dentate (H2L) coordinate to metal chlorides through oxygen atom of phenolic OH and oxygen atom of SO3‐H group by replacing H atoms and nitrogen of the quinoline ring. The magnetic studies suggested the octahedral geometrical structure for all produced polymer complexes with general formula {[ML (OH2)3] .xH2O}n (M = Cu2+, x = 1.; Co2+, x = 2 and Ni2+, x = 2) in molar ratio (1:1). Coats–Redfern and Horowitz–Metzger methods have been used for calculating the activation thermodynamic parameters of the thermal decomposition for H 2 L and its polymer complexes. The interaction between H 2 L and its transition metal complexes with the calf thymus DNA (CT‐DNA) was determined by UV–Vis spectra. Binding efficiency between H 2 L with the receptors of the prostate cancer (PDB code 2Q7L Hormone) and the breast cancer (PDB code 1JNX Gene regulation) was studied by molecular docking. The inhibition behaviour of H 2 L against the corrosion of carbon steel / HCl (2 M) solution was studied by weight loss, Tafel polarisation, electrochemical impedance spectroscopy (EIS) and electrochemical frequency modulation (EFM) techniques. The adsorption isotherm was found to be Friendlish isotherm. The morphology of inhibited carbon steel? s surface was studied using scanning electron microscope (SEM) and energy dispersive X‐ray spectroscopy (EDS). 相似文献
2.
Dr. Jordan Donat Mr. Patrick Dubourdeaux Dr. Martin Clémancey Dr. Julia Rendon Clara Gervasoni Mr. Morgan Barbier Jessica Barilone Dr. Jacques Pécaut Prof. Dr. Serge Gambarelli Prof. Dr. Pascale Maldivi Prof. Dr. Jean-Marc Latour 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(70):e202201875
Nitrene transfer reactions have emerged as one of the most powerful and versatile ways to insert an amine function to various kinds of hydrocarbon substrates. However, the mechanisms of nitrene generation have not been studied in depth albeit their formation is taken for granted in most cases without definitive evidence of their occurrence. In the present work, we compare the generation of tosylimido iron species and NTs transfer from FeII and FeIII precursors where the metal is embedded in a tetracarbene macrocycle. Catalytic nitrene transfer to reference substrates (thioanisole, styrene, ethylbenzene and cyclohexane) revealed that the same active species was at play, irrespective of the ferrous versus ferric nature of the precursor. Through combination of spectroscopic (UV-visible, Mössbauer), ESI-MS and DFT studies, an FeIV tosylimido species was identified as the catalytically active species and was characterized spectroscopically and computationally. Whereas its formation from the FeII precursor was expected by a two-electron oxidative addition, its formation from an FeIII precursor was unprecedented. Thanks to a combination of spectroscopic (UV-visible, EPR, Hyscore and Mössbauer), ESI-MS and DFT studies, we found that, when starting from the FeIII precursor, an FeIII tosyliodinane adduct was formed and decomposed into an FeV tosylimido species which generated the catalytically active FeIV tosylimide through a comproportionation process with the FeIII precursor. 相似文献
3.
Nonlinear Dynamics - Darboux and Bäcklund transformations on integrable couplings are formulated and generalized. The generalization of the theory pertains to spectral problems where the... 相似文献
4.
Detoxification of Chemical Warfare Agents Using a Zr6‐Based Metal–Organic Framework/Polymer Mixture 下载免费PDF全文
Dr. Su‐Young Moon Emmanuel Proussaloglou Gregory W. Peterson Dr. Jared B. DeCoste Morgan G. Hall Dr. Ashlee J. Howarth Prof. Joseph T. Hupp Prof. Omar K. Farha 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(42):14864-14868
Owing to their high surface area, periodic distribution of metal sites, and water stability, zirconium‐based metal–organic frameworks (Zr6‐MOFs) have shown promising activity for the hydrolysis of nerve agents GD and VX, as well as the simulant, dimethyl 4‐nitrophenylphosphate (DMNP), in buffered solutions. A hurdle to using MOFs for this application is the current need for a buffer solution. Here the destruction of the simulant DMNP, as well as the chemical warfare agents (GD and VX) through hydrolysis using a MOF catalyst mixed with a non‐volatile, water‐insoluble, heterogeneous buffer is reported. The hydrolysis of the simulant and nerve agents in the presence of the heterogeneous buffer was fast and effective. 相似文献
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Victoria A. Ternes Hannah A. Morgan Austin P. Lanquist Michael J. Murray Bradley M. Wile 《应用有机金属化学》2020,34(4):e5459
Herein we report the preparation of a series of Ru(II) complexes featuring α-iminopyridine ligands bearing thioether functionality (NNSR, where R = Me, CH2Ph, Ph). Metallation using [(p-cymene)RuCl]2 permits access to Ru complexes with a κ2-N,N donor set in which the thioether moiety remains uncoordinated. In the presence of a strong field ligand such as acetonitrile or triphenylphosphine, the p-cymene moiety is displaced, and the ligand adopts a κ3-N,N,S binding mode. These complexes are characterized using a combination of solution and solid state methods, including the crystal structure of [(NNSMe)Ru (NCMe)2Cl]Cl. The κ2-N,N-Ru(II) complexes are shown to serve as efficient precatalysts for the oxidation of sec-phenethyl alcohol at modest loadings (alcohol: Ru = 20:1), using a variety of external oxidants and solvents. The complex bearing an S-Ph donor was found to be the most active oxidation catalyst of those surveyed, suggesting that the thioether donor plays an active role in the catalytic cycle. 相似文献
9.
Gabrielle A. Leith Allison M. Rice Brandon J. Yarbrough Anna A. Berseneva Richard T. Ly Charles N. Buck III Dr. Denis Chusov Amy J. Brandt Prof. Dr. Donna A. Chen Benjamin W. Lamm Prof. Dr. Morgan Stefik Kenneth S. Stephenson Dr. Mark D. Smith Prof. Dr. Aaron K. Vannucci Dr. Perry J. Pellechia Prof. Dr. Sophya Garashchuk Prof. Dr. Natalia B. Shustova 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(15):6056-6062
The effect of donor (D)–acceptor (A) alignment on the materials electronic structure was probed for the first time using novel purely organic porous crystalline materials with covalently bound two- and three-dimensional acceptors. The first studies towards estimation of charge transfer rates as a function of acceptor stacking are in line with the experimentally observed drastic, eight-fold conductivity enhancement. The first evaluation of redox behavior of buckyball- or tetracyanoquinodimethane-integrated crystalline was conducted. In parallel with tailoring the D-A alignment responsible for “static” changes in materials properties, an external stimulus was applied for “dynamic” control of the electronic profiles. Overall, the presented D–A strategic design, with stimuli-controlled electronic behavior, redox activity, and modularity could be used as a blueprint for the development of electroactive and conductive multidimensional and multifunctional crystalline porous materials. 相似文献
10.
Morgan A. Higgins Christopher R. Maroon Jacob Townsend Xinyi Wang Konstantinos D. Vogiatzis Brian K. Long 《Journal of polymer science. Part A, Polymer chemistry》2020,58(18):2644-2653
Polymeric membranes have shown tremendous promise for the separation of CO2 from flue gas streams. However, few systematic studies have been conducted to better understand the impact that chemical functionalities have on membrane-based gas separation performance. To address this gap, we herein describe the synthesis and gas separation performance of a series of vinyl-addition polynorbornenes bearing various CO2-philic functional groups. To facilitate direct comparison between functional groups, each material was designed to maintain a common polymer backbone. Though the incorporation of CO2-philic moieties within a dense polymeric membrane is frequently hypothesized to enhance CO2 solubility, and thereby increase CO2/N2 selectivity, our results demonstrate that the incorporation of CO2-philic groups onto a common polymer backbone do not necessarily result in increased gas separation performance. Experimental and computational results demonstrate that the incorporation of amidoxime groups onto a polynorbornene backbone increase CO2/N2 selectivity, whereas commonly employed ethereal side chains only increased permeability. 相似文献