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61.
Saminathan IS Zhao J Siu KW Hopkinson AC 《Physical chemistry chemical physics : PCCP》2011,13(41):18307-18314
Protonated a(2) and a(3) (therefore doubly charged) ions in which both charges lie on the peptide backbone are formed in collision-induced dissociations of [La(III)(peptide)(CH(3)CN)(m)](3+) complexes. Abundant (a(3)+H)(2+) ions are formed from triproline (PPP) and peptides with a proline residue at the N-terminus; these peptides are the most effective in producing ions of the type (a(2)+H)(2+) and (a(3)+H)(2+). A systematic study of the effect of the location of the proline residue and other residues of aliphatic amino acids on the generation of protonated a ions is reported. Density functional theory calculations at B3LYP/6-311++G(d,p) gave the proton affinity of the a(3) ion derived from PPP to be 167.6 kcal mol(-1), 2.6 kcal mol(-1) higher than that of water. The protonated a(2) ions of diglycine and diproline and a(3) ions of triglycine have lower proton affinities and are only observed in lower abundances, possibly due to proton transfer to water in ion-molecule reactions. 相似文献
62.
63.
Dr. Zewei Quan Loriana Valentin‐Bromberg Welley Siu Loc Prof. Jiye Fang 《化学:亚洲杂志》2011,6(5):1126-1136
This review focuses on recent developments in the self‐assembly of lead chalcogenide nanocrystals into two‐ and three‐dimensional superstructures. Self‐assembly is categorized by the shapes of building blocks, including nanospheres, nanocubes, nano‐octahedra, and nanostars. In the section on nanospheres, rapid assemblies of lead chalcogenide‐based multicomponent nanocrystals with additional components, such as semiconductors, noble metals, and magnetic nanocrystals, are further highlighted. In situ self‐assembly of lead chalcogenide nanocrystals into one‐dimensional nanostructures at elevated temperatures is also covered. Each section of this paper highlights examples extracted from recent publications. Finally, relatively novel properties and applications arising from lead chalcogenide superlattices as typical examples are also discussed. 相似文献
64.
Ah 《Journal of Molecular Structure》1993,280(2-3):295-296
65.
The blue organic dye, 2,6-dichloroindophenol (DCIP), was immobilized on PEGylated Merrifield resin after a chlorination step followed by a nucleophilic substitution reaction, using microwave-assisted methodology. The final product was a blue pigmented resin that can be reversibly reduced by ascorbic acid and changes color from blue to light yellow. Structural elucidation of this immobilized indicator was confirmed through FTIR and elemental analyses. 相似文献
66.
L.W. Yang X.L. Wu G.S. Huang T. Qiu Y.M. Yang G.G. Siu 《Applied Physics A: Materials Science & Processing》2005,81(5):929-931
Highly aligned Mn-doped Zn2SiO4 nanorods were fabricated by using a modified vapor-phase evaporation method. Their microstructure and chemical bond configurations were investigated with the help of X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Fourier-transform infrared absorption spectroscopy, and X-ray photoelectron spectroscopy. The formation process of the Mn-doped Zn2SiO4 nanorods can be elucidated on the basis of a self-catalytic vapor–liquid–solid growth mechanism in which Mn chloride hydrate acts as the catalyst and impurity source. Photoluminescence measurements revealed that an intensive green luminescence peak appears at 523 nm, which corresponds to the electronic transition 4T1(4G)→6A1(6S) of Mn2+ ions. Our experimental results provide a useful approach to directly fabricate Si-based nanoscale light-emitting materials using ZnO–Zn2SiO4 composite. PACS 81.05.-t; 81.10.Bk; 81.07.-b 相似文献
67.
68.
A general formulation of the nonlinear filtering problem inRiemanman manifolds is given by use of the strong solutionsof the stochastic differential equations for the state and observationprocesses in the orthonormal frame bundles of the state andobservation process manifolds, respectively. A general Bayesformula for the conditional expectation of smooth functionsof the state process is given. This is used to give a directderivation of the Zakai equation for the general problem underconsideration. An example is presented. 相似文献
69.
70.
Summary Arsenic in marine samples was determined by gas chromatography with electron capture detection after derivatization with 2,3-dimercaptopropanol.
Biological tissues and sediments were analyzed after acid decomposition. For sea water, arsenic was preconcentrated by coprecipitation
with hydrous iron (III) oxide. The results obtained by this approach compare favourably with the certified values of the reference
materials analyzed.
Presented at the 15th International Symposium on Chromatography, Nürnberg, October 1984 相似文献