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31.
The triple phase boundary transfer of anions from the aqueous into an organic phase can be driven electrochemically here with the tetraphenylporphyrinato‐Mn(III/II) (or TPPMn) redox system in 4‐(3‐phenylpropyl)‐pyridine) (or PPP). Anions investigated are perchlorate, chloride, fluoride, and bicarbonate. The bicarbonate and fluoride transfer processes are shown to be chemically more complex compared to the perchlorate and chloride cases with UV‐vis‐spectroelectrochemical measurements indicating a combination of HCO3?/CO32? transfer processes and association of fluoride with TPPMn(III)+, respectively. In situ spectroelectrochemistry is developed for ion‐transfer voltammetry into sub‐microliter organic phase regions on mesoporous ITO conducting film electrodes. 相似文献
32.
Craig F Ferris Tara Stolberg Praveen Kulkarni Murali Murugavel Robert Blanchard D Caroline Blanchard Marcelo Febo Mathew Brevard Neal G Simon 《BMC neuroscience》2008,9(1):111
Background
With the advent of functional magnetic resonance imaging (fMRI) in awake animals it is possible to resolve patterns of neuronal activity across the entire brain with high spatial and temporal resolution. Synchronized changes in neuronal activity across multiple brain areas can be viewed as functional neuroanatomical circuits coordinating the thoughts, memories and emotions for particular behaviors. To this end, fMRI in conscious rats combined with 3D computational analysis was used to identifying the putative distributed neural circuit involved in aggressive motivation and how this circuit is affected by drugs that block aggressive behavior. 相似文献33.
Amspacher DR Blanchard CZ Fronczek FR Saraiva MC Waldrop GL Strongin RM 《Organic letters》1999,1(1):99-102
[formula: see text] An efficient and practical synthesis of 1, a unique reaction intermediate analogue of biotin-dependent carboxylases, is described. The synthesis features a selective acylation of the 1'-N of biotin. Target 1 inhibits the activity of the biotin carboxylase component of acetyl CoA carboxylase. It is the first known biotin-derived inhibitor of biotin carboxylase and should promote new kinetic and structural studies of the biotin-dependent carboxylases. 相似文献
34.
35.
Domińska M Jackowska K Krysiński P Blanchard GJ 《The journal of physical chemistry. B》2005,109(33):15812-15821
We have synthesized and characterized a family of self-assembled monolayers containing pyrene derivatives on gold and indium-doped tin oxide (ITO) substrates. The covalently bound pyrene functionalities serve as either spectroscopic or electrochemical probes of their immediate environment, and we explore their electrochemical response in this paper. When these compounds are the only constituents bound to the interfaces, the molecules enjoy significant structural freedom. The addition of aliphatic adsorbates to the interfaces serves to place the pyrene derivatives in a more restricted environment. Cyclic voltammetry shows that the organization of a monolayer with pyrene derivatives, and the position of the terminal pyrene within such monolayer, depend sensitively on the length of the pyrene tether and the presence or absence of aliphatic interfacial species, as well as the identity of the substrate. 相似文献
36.
[structure: see text] Planarized star-shaped oligothiophenes 1 have been synthesized by connecting short-chain oligothiophenes on a benzo[1,2-b:3,4-b':5,6-b' ']trithiophene central core. Their electrochemical and optical properties have been characterized by cyclic voltammetry and UV-visible spectroscopy, respectively. These results associated with theoretical calculations show the advantage of benzotrithiophene as a central core in terms of pi-electron delocalization. 相似文献
37.
Covalent adlayer growth on a diamond thin film surface 总被引:1,自引:0,他引:1
Krysiński P Show Y Stotter J Blanchard GJ 《Journal of the American Chemical Society》2003,125(42):12726-12728
The surface of boron-doped diamond thin films can be modified by exposure to a strong oxidizing agent, resulting in the formation of -OH and =O terminated diamond. The -OH groups are reacted with an acid chloride to produce a covalently bound, modified diamond thin film surface. The demonstration of these reactions allows for the facile modification of diamond surfaces using techniques well established for oxide surfaces. Characterization of the covalently bound species shows submonolayer coverage, and time-resolved fluorescence measurements are reflective of the highly featured nature of the diamond film. 相似文献
38.
[structure: see text] The total synthesis of formamicinone (2), the aglycone of formamicin (1), has been accomplished via the late-stage Suzuki cross-coupling of fragments 5 and 6, the macrolactonization of seco ester 14, and the Mukaiyama aldol reaction of aldehyde 3 and methyl ketone 4. An efficient and highly stereoselective second generation synthesis of vinyl iodide 6 is also described. 相似文献
39.
MacFarlane WA Bobroff J Alloul H Mendels P Blanchard N Collin G Marucco J 《Physical review letters》2000,85(5):1108-1111
We present a study of the spin dynamics of magnetic defects induced by Li substitution of the plane Cu in the normal state of YBa2Cu3O6+x. The fluctuations of the coupled Cu magnetic moments in the vicinity of Li are probed by near-neighbor 89Y and 7Li NMR spin lattice relaxation. The data indicate that the magnetic perturbation fluctuates as a single entity with a correlation time tau which scales with the local static susceptibility. This behavior is reminiscent of the low T Kondo state of magnetic impurities in conventional metals. Surprisingly it extends well above the "Kondo" temperature for the underdoped pseudogapped case. 相似文献
40.
Ross A. Hatton Nicholas P. Blanchard Anthony J. Miller S.R.P. Silva 《Physica E: Low-dimensional Systems and Nanostructures》2007,37(1-2):124
A water-soluble composite of oxidised multi-wall carbon nanotubes and sulphonic acid sodium salt derivatised copper phthalocyanine for application in bi-layer organic solar cells is reported. Measurements of the topography of thin films of this novel material and of the valence electronic structure of its two components are used to rationalise the photovoltaic characteristics of a model organic heterojunction utilising the nanocomposite as the hole-extracting electrode and donor layer. 相似文献