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91.
92.
Jun Ling Zhicheng Zheng Anna Khler Axel H. E. Müller 《Macromolecular rapid communications》2014,35(1):52-55
Imitating the natural “energy cascade” architecture, we present a single‐molecular rod‐like nano‐light harvester (NLH) based on a cylindrical polymer brush. Block copolymer side chains carrying (9,9‐diethylfluoren‐2‐yl)methyl methacrylate units as light absorbing antennae (energy donors) are tethered to a linear polymer backbone containing 9‐anthracenemethyl methacrylate units as emitting groups (energy acceptors). These NLHs exhibit very efficient energy absorption and transfer. Moreover, we manipulate the energy transfer by tuning the donor–acceptor distance.
93.
94.
Toralf Peymann Axel Herzog Carolyn B. Knobler M. Frederick Hawthorne 《Angewandte Chemie (International ed. in English)》1999,38(8):1061-1064
No explosion , but per-B-hydroxylation occurs if the icosahedral boron hydrides [closo-B12H12]2− (see picture), [closo-CB11H12]−, or closo-1,12-(CH2OH)2-1,12-C2B10H10 are refluxed in 30 % hydrogen peroxide. Thus, the three isoelectronic species [closo-B12(OH)12]2−, [closo-1-H-1-CB11(OH)11]−, and closo-1,12-H2-1,12-C2B10(OH)10 were obtained. ○=BH, ○=BOH. 相似文献
95.
For the 9-dimensional bicovariant differential calculi on the quantum group O(O
q(3)) several kinds of exterior algebras are examined. The corresponding dimensions, bicovariant subbimodules and eigenvalues of the antisymmetrizer are given. Exactly one of the exterior algebras studied by the authors has a unique left invariant form with maximal degree. 相似文献
96.
Ionel Haiduc Gellert Mezei Rodica Micu‐Semeniuc Frank T. Edelmann Axel Fischer 《无机化学与普通化学杂志》2006,632(2):295-300
The three (O‐methyl)‐p‐ethoxyphenyldithiophosphonato triphenylphosphine complexes of copper, silver and gold, [(Ph3P)nM{S2P(OMe)C6H4OEt‐p}] (M = Cu, n = 2; M = Ag, Au, n = 1) investigated structurally by X‐ray diffraction exhibit remarkable structural differences. The copper compound is a four‐coordinate chelate monomer with Cu–S 2.4417(6) and 2.5048(6) Å; P–Cu–S 104.24(2)–114.01(2)°; Cu–S–P 82.49(3)° and 80.85(2)°. The silver compound is a cyclic dimer with bridging dithiophosphonato ligands and three‐coordinate silver atoms [Ag–S 2.5371(5) and 2.6867(5) Å; P–Ag–S 122.88(2)° and 122.17(2)°; Ag–S–P 89.32(2)° and 103.56(2)°]. The gold compound is monomeric with linear dicoordinate gold [Au–S 2.3218(6) Å; P–Au–S 177.72(2)°, Au–S–P 100.97(3)°]. 相似文献
97.
van Axel Castelli V Dalla Cort A Mandolini L Reinhoudt DN Schiaffino L 《Chemistry (Weinheim an der Bergstrasse, Germany)》2000,6(7):1193-1198
The base induced addition of benzenethiol to 2-cyclohexen-1-one and its 4,4-, 5,5- and 6,6-dimethyl derivatives is catalysed by a salophen-uranyl based metallocleft 2 in chloroform solution with high turnover efficiency and low product inhibition. Analysis of rate data coupled with equilibrium measurements for complexation of the catalyst with the enone reactants and addition products shows that the catalytic mechanism involves the three main steps typical of single-substrate enzymatic processes, namely substrate binding and recognition, transformation of the bound substrate, and release of the reaction product. Unlike the reference salophen-uranyl 1, catalyst 2 is endowed with a structured binding site responsible for a high degree of substrate specificity among the investigated enones, due to recognition of their shape and size. 相似文献
98.
The synthesis, structure, and physical properties of ionic liquids (IL) bearing the novel [Al(O–C6H4–CN)4]– ion as counterion to the commonly used [NR4]+, [PR4]+ and imidazolium ions are reported. Both the influence of the alkyl chain length as well as the functionalization with cyano groups is studied. These ILs are easily obtained by reaction of Ag[Al(O–C6H4–CN)4] with the corresponding ammonium, phosphonium, and imidazolium halides. The stability towards electrophilic cations was investigated. All prepared salts have a window for the liquid phase of ca. 200 °C and are thermally stable up to 450 °C. The solid‐state structures reveal only weak cation ··· anion and anion ··· anion interactions in accord with the observed low melting points (glass transition points). 相似文献
99.
100.
We demonstrate electrically pumped InGaAsP two-dimensional Bragg grating (2DBG) lasers with two line defects. The 2DBG structure uses a weak 2D index perturbation surface grating to control the optical modes in the plane of the wafer. Measurements of the 2DBG lasers show that modal control in both the longitudinal and transverse directions is due to the gratings and defects. The 2DBG lasers are promising candidates for single-mode, high power, and high efficiency large-area lasers. 相似文献