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排序方式: 共有264条查询结果,搜索用时 15 毫秒
261.
Sarah Goler Jun Yan Vittorio Pellegrini Aron Pinczuk 《Solid State Communications》2012,152(15):1289-1293
The magneto-phonon resonance or MPR occurs in semiconductor materials when the energy spacing between Landau levels is continuously tuned to cross the energy of an optical phonon mode. MPRs have been largely explored in bulk semiconductors, in two-dimensional systems and in quantum dots. Recently there has been significant interest in the MPR interactions of the Dirac fermion magneto-excitons in graphene, and a rich splitting and anti-crossing phenomena of the even parity long wavelength optical phonon mode have been theoretically proposed and experimentally observed. The MPR has been found to crucially depend on disorder in the graphene layer. This is a feature that creates new venues for the study of interplays between disorder and interactions in the atomic layers. We review here the fundamentals of MRP in graphene and the experimental Raman scattering works that have led to the observation of these phenomena in graphene and graphite. 相似文献
262.
Kimberly N. Karin Mohammed A. Mustafa Aron H. Lichtman Justin L. Poklis 《Journal of separation science》2023,46(22):2300395
Interest has increased in the role of N-acyl amino acids in a variety of disease states and as potential pharmacotherapies. Recently, N-oleoyl glycine and N-oleoyl alanine have shown promise in reducing the rewarding effects of drugs of abuse and alleviating withdrawal signs in rodent models. Previously published methods for the quantitation of these analytes by high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) in tissue were part of extensive lipidomic panels which may result in limited sensitivity and selectivity and also reported low recovery. Presented is a method for the extraction and HPLC-MS/MS analysis of N-oleoyl glycine and N-oleoyl alanine. The bias and precision of the assay were determined to be within ± 20%. The method was shown to be reliable and robust, with over 90% recovery for the low-level analytes. Increasing concentrations of N-oleoyl glycine and N-oleoyl alanine were quantitated in mouse brain and plasma following exogenous administration. This method was developed to serve to support studies investigating the pharmacokinetics and involvement of N-oleoyl glycine and N-oleoyl alanine in drug dependence and other diseases. 相似文献
263.
John Buckeridge Keith T. Butler C. Richard A. Catlow Andrew J. Logsdail David O. Scanlon Stephen A. Shevlin Scott M. Woodley Alexey A. Sokol Aron Walsh 《ChemInform》2015,46(31):no-no
A multiscale quantum‐chemical approach is used for examining the electronic structure of eight known TiO2 polymorphs and aligning their ionization potential and electron affinity relative to an absolute energy reference. 相似文献
264.
Kai-Oliver Brenske Dr. Meike Emondts Sven T. Hörnig Sinan Panitz Maria I. Pieper Aron Ligori Alexander Schacht Johanna Henkel Prof. Dr. Jürgen Klankermayer Prof. Dr. Andreas Herrmann 《Angewandte Chemie (International ed. in English)》2023,62(22):e202300531
Enhancing NMR signals of biomacromolecules by hyperpolarization offers exciting opportunities for diagnostic applications. However, their hyperpolarization via parahydrogen remains challenging as specific catalytic interactions are required, which are difficult to tune due to the large size of the biomolecule and its insolubility in organic solvents. Herein, we show the unprecedented hyperpolarization of the cancer-targeting DNA aptamer AS1411. By screening different molecular motifs for an unsaturated label in nucleosides and in DNA oligomers, we were able to identify structural prerequisites for the hyperpolarization of AS1411. Finally, adjusting the polarity of AS1411 by complexing the DNA backbone with amino polyethylene glycol chains allowed the hydrogenation of the label with parahydrogen while the DNA structure remains stable to maintain its biological function. Our results are expected to advance hyperpolarized molecular imaging technology for disease detection in the future. 相似文献