排序方式: 共有79条查询结果,搜索用时 218 毫秒
1.
E. Ühlein W. Scherman F. Asinger A. Warner P. Kratochvil G. Kirschstein H. Bergmann H. D. Cremer U. Grigull E. Schleitzer E. Best R. Honerjäger H. Schäfer K. -H. König A. Sippel Hj. Schönert W. Koch B. Frisch H. G. Kilian R. Hähnel H. H. Pfeiffer 《Colloid and polymer science》1966,213(1-2):157-174
Ohne Zusammenfassung 相似文献
2.
3.
O. S. Mishina M. Scherman P. Lombardi J. Ortalo D. Felinto A. S. Sheremet D. V. Kupriyanov J. Laurat E. Giacobino 《Optics and Spectroscopy》2011,111(4):583-588
Electromagnetically induced transparency (EIT) has led to several quantum optics effects such as lasing without inversion
or squeezed light generation. More recently quantum memories based on EIT have been experimentally implemented in different
systems such as alkali metal atoms. In this system the excited state of the optical transition splits into several sublevels
due to the hyperfine interaction. However, most of the theoretical models used to describe the experimental results are based
on a Λ-system with only one excited state. In this article, we present a theoretical model for the Λ-type interaction of two
light, fields and an atomic system with multiple excited state. In particular we show that if the control and probe fields
are orthogonally circularly polarized the EIT effect in an alkali-metal vapor can almost disappears. We also identify the
reasons of this reduction and propose a method to recover the transparency via velocity selective optical pumping. 相似文献
4.
5.
6.
Tancini F Yebeutchou RM Pirondini L De Zorzi R Geremia S Scherman OA Dalcanale E 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(48):14313-14321
The outstanding complexing properties of tetraphosphonate cavitands towards N‐methylpyridinium salts were exploited to realise a new class of linear and cyclic AABB supramolecular polymers through host–guest interactions. The effectiveness of the selected self‐association processes was tested by 1H NMR studies, whereas microcalorimetric analyses clarified the binding thermodynamics and revealed the possibility of tuning entropic contributions by acting on the flexibility of the guest linker. Although the formation of linear polymeric chains for a rigid system was demonstrated by X‐ray analysis, the presence of a concentration‐dependent ring–chain equilibrium was indicated by solution viscosity measurements in the case of a very flexible ditopic BB guest co‐monomer. 相似文献
7.
Tian F Cziferszky M Jiao D Wahlström K Geng J Scherman OA 《Langmuir : the ACS journal of surfaces and colloids》2011,27(4):1387-1390
We demonstrate a supramolecular peptide separation approach by the selective immobilization of peptides bearing an N-terminal tryptophan onto a CB[8]-modified gold substrate, followed by electrochemical release. The CB[8]-stabilized heteroternary complexes were characterized by (1)H NMR, ESI-MS, UV/vis, and fluorescence spectroscopy and cyclic voltammetry. Micropatterned CB[8]-modified gold substrates were found to trap only the recognizable N-tryptophan-containing peptides from a peptide mixture that could be visualized as green peptide arrays under fluorescence microscopy. Subsequently, the bound peptides were released from the modified substrates by the controlled single-electron reduction of viologen. The fully reversible trap-and-release process was repeated for 13 cycles, and the cumulative release profile of the dye-peptide conjugate was monitored by fluorescence spectroscopy, indicating that no degradation occurred. 相似文献
8.
A series of bisimidazolium salts were synthesized as novel guests for the macrocyclic host molecule cucurbit[8]uril (CB[8]). These bisimidazolium-CB[8] binary complexes exhibited a unique cage structure with the imidazolium rings acting as lids, leading to a size-dependent binding selectivity by altering the hydrophobic linker between the two imidazolium moieties. This new class of CB[8] complexes was also capable of binding small solvent molecules, including acetone, acetonitrile, diethyl ether, and tetrahydrofuran (THF) in an aqueous environment. 相似文献
9.
Ziyi Yu Jing Zhang Roger J. Coulston Richard M. Parker Frank Biedermann Xin Liu Oren A. Scherman Chris Abell 《Chemical science》2015,6(8):4929-4933
Host–guest assembly in droplet-based microfluidics opens a new avenue for fabricating supramolecular hydrogel microcapsules with high monodispersity and controlled functionality. In this paper, we demonstrate a single emulsion microdroplet platform to prepare microcapsules with supramolecular hydrogel skins from host molecule cucurbit[8]uril and guest polymer anthracene-functionalized hydroxyethyl cellulose. In contrast to construction of microcapsules from a droplet-in-droplet double emulsion, here the electrostatic attraction between charged polymer and surfactant facilitates formation of defined supramolecular hydrogel skins in a single emulsion. Furthermore, by taking advantage of dynamic interactions and the tunable cross-linked supramolecular hydrogel network, it is possible to prepare microcapsules with triggered and UV-controlled molecular permeability. These could be potentially used in a delivery system for e.g. agrochemicals, nutraceuticals or cosmetics. 相似文献
10.
Supramolecular Nested Microbeads as Building Blocks for Macroscopic Self‐Healing Scaffolds 下载免费PDF全文
Dr. Ziyi Yu Dr. Ji Liu Dr. Cindy Soo Yun Tan Prof. Oren A. Scherman Prof. Chris Abell 《Angewandte Chemie (International ed. in English)》2018,57(12):3079-3083
The ability to construct self‐healing scaffolds that are injectable and capable of forming a designed morphology offers the possibility to engineer sustainable materials. Herein, we introduce supramolecular nested microbeads that can be used as building blocks to construct macroscopic self‐healing scaffolds. The core–shell microbeads remain in an “inert” state owing to the isolation of a pair of complementary polymers in a form that can be stored as an aqueous suspension. An annealing process after injection effectively induces the re‐construction of the microbead units, leading to supramolecular gelation in a preconfigured shape. The resulting macroscopic scaffold is dynamically stable, displaying self‐recovery in a self‐healing electronic conductor. This strategy of using the supramolecular assembled nested microbeads as building blocks represents an alternative to injectable hydrogel systems, and shows promise in the field of structural biomaterials and flexible electronics. 相似文献