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231.
Dr. Amanda J Welford Dr. John J. Caldwell Dr. Manjuan Liu Meirion Richards Dr. Nathan Brown Dr. Cara Lomas Dr. Graham J. Tizzard Dr. Mateusz B. Pitak Dr. Simon J. Coles Prof. Suzanne A. Eccles Dr. Florence I. Raynaud Prof. Ian Collins 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(16):5657-5664
The 2,11‐cembranoid family of natural products has been used as inspiration for the synthesis of a structurally simplified, functionally diverse library of octahydroisobenzofuran‐based compounds designed to augment a typical medicinal chemistry library screen. Ring‐closing metathesis, lactonisation and SmI2‐mediated methods were exemplified and applied to the installation of a third ring to mimic the nine‐membered ring of the 2,11‐cembranoids. The library was assessed for aqueous solubility and permeability, with a chemical‐space analysis performed for comparison to the family of cembranoid natural products and a sample set of a screening library. Preliminary investigations in cancer cells showed that the simpler scaffolds could recapitulate the reported anti‐migratory activity of the natural products. 相似文献
232.
Dr. Maria A. Palacios Dr. Eufemio Moreno Pineda Dr. Sergio Sanz Dr. Ross Inglis Dr. Mateusz B. Pitak Dr. Simon J. Coles Dr. Marco Evangelisti Prof. Hiroyuki Nojiri Christian Heesing Prof. Euan K. Brechin Prof. Jürgen Schnack Prof. Richard E. P. Winpenny 《Chemphyschem》2016,17(1):55-60
Keplerates are molecules that contain metal polyhedra that describe both Platonic and Archimedean solids; new copper keplerates are reported, with physical studies indicating that even where very high molecular symmetry is found, the low‐temperature physics does not necessarily reflect this symmetry. 相似文献
233.
A Bifunctional Electrocatalyst for Oxygen Evolution and Oxygen Reduction Reactions in Water 下载免费PDF全文
Prof. Dr. Wolfgang Schöfberger Dipl.‐Ing. Felix Faschinger Samir Chattopadhyay Snehadri Bhakta Biswajit Mondal Prof. Dr. Johannes A. A. W. Elemans Prof. Dr. Stefan Müllegger M. Sc. Stefano Tebi Prof. Dr. Reinhold Koch Priv.‐Doz. Dr. Florian Klappenberger Dipl.‐Chem. Mateusz Paszkiewicz Prof. Dr. Johannes V. Barth Dr. Eva Rauls Hazem Aldahhak Prof. Dr. Wolf Gero Schmidt Prof. Dr. Abhishek Dey 《Angewandte Chemie (International ed. in English)》2016,55(7):2350-2355
Oxygen reduction and water oxidation are two key processes in fuel cell applications. The oxidation of water to dioxygen is a 4 H+/4 e? process, while oxygen can be fully reduced to water by a 4 e?/4 H+ process or partially reduced by fewer electrons to reactive oxygen species such as H2O2 and O2?. We demonstrate that a novel manganese corrole complex behaves as a bifunctional catalyst for both the electrocatalytic generation of dioxygen as well as the reduction of dioxygen in aqueous media. Furthermore, our combined kinetic, spectroscopic, and electrochemical study of manganese corroles adsorbed on different electrode materials (down to a submolecular level) reveals mechanistic details of the oxygen evolution and reduction processes. 相似文献
234.
A simple method for assessment and minimization of errors in determination of electrophoretic or electroosmotic mobilities and velocities associated with the axial electric field distortion 下载免费PDF全文
It is commonly accepted that the modern CE instruments equipped with efficient cooling system enable accurate determination of electrophoretic or electroosmotic mobilities. It is also often assumed that velocity of migration in a given buffer is constant throughout the capillary length. It is simultaneously neglected that the noncooled parts of capillary produce extensive Joule heating leading to an axial electric field distortion, which contributes to a difference between the effective and nominal electric field potentials and between velocities in the cooled and noncooled parts of capillary. This simplification introduces systematic errors, which so far were however not investigated experimentally. There was also no method proposed for their elimination. We show a simple and fast method allowing for estimation and elimination of these errors that is based on combination of a long‐end and short‐end injections. We use it to study the effects caused by variation of temperature, electric field, capillary length, and pH. 相似文献
235.
Double Deposition and Stripping Steps for Trace Determination of Au(III) Using Anodic Stripping Voltammetry 下载免费PDF全文
A new way of decreasing the detection limit ‐ double deposition and stripping steps was proposed to determine trace amounts of gold(III) by anodic stripping voltammetry. Two carbon composite electrodes that differed drastically in their surface areas were used for the measurements. The calibration graph was linear from 1×10?9 to 1×10?8 mol L?1 following deposition time of 300 s at the first and the second electrode. The detection limit was found to be 2.3×10?10 and 1.4×10?11 mol L?1 for deposition time 600 and 2400 s, respectively. It is the lowest detection limit obtained so far for gold(III) determination in stripping voltammetry. 相似文献
236.
Dr. Justyna Kalisz Dr. Wojciech Nogala Dr. Wojciech Adamiak Mateusz Gocyla Prof. Hubert H. Girault Prof. Marcin Opallo 《Chemphyschem》2021,22(13):1352-1360
H2O2 is a versatile chemical and can be generated by the oxygen reduction reaction (ORR) in proton donor solution in molecular solvents or room temperature ionic liquids (IL). We investigated this reaction at interfaces formed by eleven hydrophobic ILs and acidic aqueous solution as a proton source with decamethylferrocene (DMFc) as an electron donor. H2O2 is generated in colorimetrically detectable amounts in biphasic systems formed by alkyl imidazolium hexafluorophosphate or tetraalkylammonium bis(trifluoromethylsulfonyl)imide ionic liquids. H2O2 fluxes were estimated close to liquid|liquid interface by scanning electrochemical microscopy (SECM). Contrary to the interfaces formed by hydrophobic electrolyte solution in a molecular solvent, H2O2 generation is followed by cation expulsion to the aqueous phase. Weak correlation between the H2O2 flux and the difference between DMFc/DMFc+ redox potential and 2 electron ORR standard potential indicates kinetic control of the reaction. 相似文献
237.
We apply lattice point counting methods to compute the multiplicities in the plethysm of \(\textit{GL}(n)\). Our approach gives insight into the asymptotic growth of the plethysm and makes the problem amenable to computer algebra. We prove an old conjecture of Howe on the leading term of plethysm. For any partition \(\mu \) of 3, 4, or 5, we obtain an explicit formula in \(\lambda \) and k for the multiplicity of \(S^\lambda \) in \(S^\mu (S^k)\). 相似文献
238.
We prove the existence of boundary limits of ratios of positive harmonic functions for a wide class of Markov processes with jumps and irregular (possibly disconnected) domains of harmonicity, in the context of general metric measure spaces. As a corollary, we prove the uniqueness of the Martin kernel at each boundary point, that is, we identify the Martin boundary with the topological boundary. We also prove a Martin representation theorem for harmonic functions. Examples covered by our results include: strictly stable Lévy processes in R d with positive continuous density of the Lévy measure; stable-like processes in R d and in domains; and stable-like subordinate diffusions in metric measure spaces. 相似文献
239.
Preparation and properties of textile materials modified with triclosan‐loaded polylactide microparticles 下载免费PDF全文
Agnieszka Karaszewska Irena Kamińska Magdalena Kiwała Mariusz Gadzinowski Mateusz Gosecki Stanislaw Slomkowski 《先进技术聚合物》2017,28(9):1185-1193
A convenient and simple method for preparation of commercial nonwovens with antimicrobial properties was elaborated. The process consists in preparation of poly(l ‐lactide) microspheres (from poly(l ‐lactide) with M n = 10,560 and M w /M n = 1.39) containing triclosan (5‐chloro‐2‐(2,4‐dichlorophenoxy) phenol) and loading them onto the nonwovens. The microspheres were prepared by spray drying (D n = 3.91 μm, D w /D n = 2.43) and oil‐in‐water emulsification‐solvent evaporation method (D n = 5.84 μm, D w /D n = 1.25). Content of triclosan in microspheres ranged from 4.65 to 4.95 wt%. The antibacterial nonwovens were prepared by padding of the fibers with the microspheres using the microsphere suspension. The resulting antibacterial nonwovens were examined using inhibition zone measurement method. Inhibition zones from 4 to 9 mm indicated that the modified nonwovens had antibacterial properties against Gram (+)—Staphylococcus aureus and Gram (?)—Klebsiella pneumoniae . Nonwovens were conditioned up to 12 months at relative humidity <5%, 50%, and 100% in desiccators and up to 6 months air‐conditioning system at relative humidity = 65%. Antimicrobial activity of the modified nonwovens was examined as a function of time and air humidity. Time of conditioning has strong influence on antibacterial activity, whereas the impact of the air humidity was negligible. All nonwovens had antibacterial properties even after 12 months of conditioning. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
240.
Mateusz Michałek 《Comptes Rendus Mathematique》2011,349(1-2):67-69
In this short Note we present an infinite family of arbitrary high dimensional counterexamples to the King's conjecture. 相似文献