600-00-0Relevant articles and documents
Grafting and coloring onto silver nanoparticles by photoinduced surface modification
Zhang, Hucheng,Zhang, Liwei,Wang, Jianji
, p. 13206 - 13207 (2009)
(Figure Presented) Surface modification of metal nanostructures can create multifunctional materials potentially very useful in many application fields and, consequently, has been the subject of intensive studies. This work reported the modification of silver nanoparticles (Ag NPs) by UV-induced interface reactions, a method controllable in both the color and the surface chemistry of the nanoparticles. Using poly(N-vinyl-2-pyrrolidone) (PVP) as the protecting polymer, Ag NPs were synthesized in ethanol and then mixed with F-bromoisobutyric acid (BIBA). When the mixture is exposed to UV irradiation, Ag NPs present themselves in a serial tone from pale blue to blue, dark blue, and finally purple with the progress of the interface reactions. It is shown that these color changes are directly related to the chemical components on the surface of Ag NPs, and hence the correlation of the colors with the chemical states of main components on the surface of Ag NPs has been made during the course of interface reactions.
Structure-LCST relationships for end-functionalized water-soluble polymers: An "accelerated" approach to phase behaviour studies
Jana, Satyasankar,Rannard, Steven P.,Cooper, Andrew I.
, p. 2962 - 2964 (2008/02/11)
A novel "high throughput" technique for LCST measurement was developed which is able to identify the effect of subtle changes in end group composition on the aqueous phase behaviour of water-soluble poly(2- (dimethylamino)ethyl methacrylate). The Royal Society of Chemistry.
Spin trapping of superoxide, alkyl- and lipid-derived radicals with derivatives of the spin trap EPPN
Stolze, Klaus,Udilova, Natascha,Rosenau, Thomas,Hofinger, Andreas,Nohl, Hans
, p. 1717 - 1726 (2007/10/03)
The N-t-butyl-α-phenylnitrone derivative N-2-(2-ethoxycarbonyl-propyl)-α-phenylnitrone (EPPN) has recently been reported to form a superoxide spin adduct (t1/2=5.25min at pH 7.0), which is considerably more stable than the respective N-t-butyl-α -phenylnitrone or 5,5-dimethylpyrroline N-oxide adducts (t1/2 ~10 and 45s, respectively). In continuation of our previous studies on structure optimization of 5-(ethoxycarbonyl)-5-methyl-1-pyrroline N-oxide derivatives, a series of six different EPPN derivatives was synthesized and characterized by 1H NMR, 13C NMR and IR spectroscopy. The ethoxy group of EPPN was replaced by a propoxy, iso-propoxy, n-butoxy, sec-butoxy, and tert-butoxy moiety, as well as the phenyl by a pyridyl ring. Electron spin resonance spectra and stabilities of the superoxide adducts of the propoxy derivatives were found to be similar to those of the respective EPPN adduct, whereas the electron spin resonance spectra of the superoxide adducts of N-2-(2-ethoxycarbonyl-propyl)-α-(4-pyridyl) nitrone and the butoxy derivatives were accompanied by decomposition products. In contrast to the 5-(ethoxycarbonyl)-5-methyl-1-pyrroline N-oxide series, no significant improvement of the superoxide adduct stability could be obtained when the ethoxy group was replaced by other substituents. Carbon centered radical adducts derived from methanol, ethanol, formic acid and linoleic acid hydroperoxide were more stable than those of 5,5-dimethylpyrroline N-oxide, whereas among the alkoxyl radicals only the methoxyl radical adduct could be detected.