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861.
Dey SK Long YT Chowdhury S Sutherland TC Mandal HS Kraatz HB 《Langmuir : the ACS journal of surfaces and colloids》2007,23(12):6475-6477
This study describes the electron transfer (ET) phenomenon through a series of (Pro-Hyp-Gly) repeat units containing collagen mimics. The peptides contain redox-active ferrocene (Fc) and thiol-functionalized cystein (Cys) at the N- and C-terminals, respectively. Peptide films were prepared on gold surfaces and characterized by X-ray photoelectron spectroscopy (XPS), ellipsometry, and Fourier transform-reflection absorption infrared spectroscopy (FT-RAIRS). Electrochemical investigations of the films showed a linear but weakly distance-dependent ET. The importance of H-bonding was realized, and the possibility of a conformationally gated ET mechanism has been discussed. 相似文献
862.
Yuhua Long 《Journal of Difference Equations and Applications》2020,26(7):966-986
In the present paper, we apply the method of invariant sets of descending flow to establish a series of criteria to ensure that a second-order nonlinear functional difference equation with periodic boundary conditions possesses at least one trivial solution and three nontrivial solutions. These nontrivial solutions consist of sign-changing solutions, positive solutions and negative solutions. Moreover, as an application of our theoretical results, an example is elaborated. Our results generalize and improve some existing ones. 相似文献
863.
864.
865.
866.
CRITICAL MAGNETIC SHEAR FOR THE TOKAMAK IDEAL INTERNAL KINK MODE IN THE ION KINETIC REGIME 下载免费PDF全文
It is shown that for the ideal internal kink mode of tokamak plasma, there exists a critical magnetic shear s0c for its excitation when the finite ion Larmor radius effect is considered in the mode singular layer. This can be related to the sudden onset of the sawtooth and also to the stabilization of the sawtooth by the trapped hot ions observed experimentally. The alpha particle effect on this mode is revisited and some new results are reported. 相似文献
867.
Sai‐Rong Fan Guo‐Qiang Cai Long‐Guan Zhu Hong‐Ping Xiao 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(4):m177-m179
The title compound, [Cu(C7H3O6S)2(C10H9N3)2][CuI(C10H9N3)2]2·2H2O, consists of anionic CuII moieties, cationic CuI species and uncoordinated water molecules. The anionic dimeric unit consists of one crystallographically independent fully deprotonated 5‐sulfosalicylate (2‐oxido‐5‐sulfonatobenzoate) anion, a di‐2‐pyridylamine group and a CuII atom. Each CuII atom is five‐coordinate within a square‐pyramidal geometry. The anion lies on a special position of site symmetry. In the cationic monomer, the CuI atom adopts tetrahedral geometry. The cations and anions are connected by O—H·O and N—H·O hydrogen bonds. 相似文献
868.
Dr. Graeme J. Stasiuk Dr. Florencia Minuzzi Dr. Myra Sae‐Heng Charlotte Rivas Dr. Hans‐Paul Juretschke Dr. Lorenzo Piemonti Dr. Peter R. Allegrini Dr. Didier Laurent Andrew R. Duckworth Prof. Andrew Beeby Prof. Guy A. Rutter Prof. Nicholas J. Long 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(13):5023-5033
Despite the contribution of changes in pancreatic β‐cell mass to the development of all forms of diabetes mellitus, few robust approaches currently exist to monitor these changes prospectively in vivo. Although magnetic‐resonance imaging (MRI) provides a potentially useful technique, targeting MRI‐active probes to the β cell has proved challenging. Zinc ions are highly concentrated in the secretory granule, but they are relatively less abundant in the exocrine pancreas and in other tissues. We have therefore developed functional dual‐modal probes based on transition‐metal chelates capable of binding zinc. The first of these, Gd ?1 , binds ZnII directly by means of an amidoquinoline moiety (AQA), thus causing a large ratiometric Stokes shift in the fluorescence from λem=410 to 500 nm with an increase in relaxivity from r1=4.2 up to 4.9 mM ?1 s?1. The probe is efficiently accumulated into secretory granules in β‐cell‐derived lines and isolated islets, but more poorly by non‐endocrine cells, and leads to a reduction in T1 in human islets. In vivo murine studies of Gd ?1 have shown accumulation of the probe in the pancreas with increased signal intensity over 140 minutes. 相似文献
869.
Qingwen Tian Guigan Fang Yingqiao Shi Laibao Ding Aixiang Pan Long Liang Naixu Li Jiancheng Zhou 《Research on Chemical Intermediates》2017,43(3):1395-1407
A novel SrTiO3/BiPO4 heterostructure with different amounts of SrTiO3 have been successfully prepared through the hydrothermal process. The photocatalysts were characterized by X-ray powder diffraction, UV–Vis diffuse reflectance spectroscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, transmission electron microscopy, high-resolution transmission electron microscopy, and X-ray photoelectron spectroscopy. The photocatalytic performance was evaluated by degrading the methylene blue dye solution under UV light. Results showed that the samples displayed excellent photocatalytic degradation efficiency due to the highly efficient suppression of the recombination of electron–hole pairs. A possible mechanism of SrTiO3/BiPO4 heterojunctions was discussed. The research indicated that the as-prepared SrTiO3/BiPO4 heterogeneous photocatalyst can be used as an effective material for degrading industrial organic wastewater. 相似文献
870.
The two-dimensional cyano-bridged coordination polymer Er(H(2)O)(4)[W(CN)(8)] exhibits a magnetic transition at 12 K and an unusual field-dependent transition from short-range to ferromagnetic ordering. 相似文献