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51.
52.
[reaction: see text] Highly substituted beta-lactams have been isolated as the major product of the reaction of dimethoxycarbene with selected isocyanates. This reaction offers the potential for rapid access into a variety of highly functionalized species. 相似文献
53.
Stephanie J. Rigby Soo-Keun Lee Peter K.J. Robertson 《Applied Surface Science》2006,252(22):7948-7952
The use of Raman and anti-stokes Raman spectroscopy to investigate the effect of exposure to high power laser radiation on the crystalline phases of TiO2 has been investigated. Measurement of the changes, over several time integrals, in the Raman and anti-stokes Raman of TiO2 spectra with exposure to laser radiation is reported. Raman and anti-stokes Raman provide detail on both the structure and the kinetic process of changes in crystalline phases in the titania material. The effect of laser exposure resulted in the generation of increasing amounts of the rutile crystalline phase from the anatase crystalline phase during exposure. The Raman spectra displayed bands at 144 cm−1 (A1g), 197 cm−1 (Eg), 398 cm−1 (B1g), 515 cm−1 (A1g), and 640 cm−1 (Eg) assigned to anatase which were replaced by bands at 143 cm−1 (B1g), 235 cm−1 (2 phonon process), 448 cm−1 (Eg) and 612 cm−1 (A1g) which were assigned to rutile. This indicated that laser irradiation of TiO2 changes the crystalline phase from anatase to rutile. Raman and anti-stokes Raman are highly sensitive to the crystalline forms of TiO2 and allow characterisation of the effect of laser irradiation upon TiO2. This technique would also be applicable as an in situ method for monitoring changes during the laser irradiation process. 相似文献
54.
Enzyme‐Mediated Site‐Specific Bioconjugation of Metal Complexes to Proteins: Sortase‐Mediated Coupling of Copper‐64 to a Single‐Chain Antibody 下载免费PDF全文
Dr. Brett M. Paterson Dr. Karen Alt Charmaine M. Jeffery Prof. Roger I. Price Shweta Jagdale Dr. Sheena Rigby Dr. Charlotte C. Williams Prof. Karlheinz Peter Prof. Christoph E. Hagemeyer Assoc. Prof. Paul S. Donnelly 《Angewandte Chemie (International ed. in English)》2014,53(24):6115-6119
The enzyme‐mediated site‐specific bioconjugation of a radioactive metal complex to a single‐chain antibody using the transpeptidase sortase A is reported. Cage amine sarcophagine ligands that were designed to function as substrates for the sortase A mediated bioconjugation to antibodies were synthesized and enzymatically conjugated to a single‐chain variable fragment. The antibody fragment scFvanti‐LIBS targets ligand‐induced binding sites (LIBS) on the glycoprotein receptor GPIIb/IIIa, which is present on activated platelets. The immunoconjugates were radiolabeled with the positron‐emitting isotope 64Cu. The new radiolabeled conjugates were shown to bind selectively to activated platelets. The diagnostic potential of the most promising conjugate was demonstrated in an in vivo model of carotid artery thrombosis using positron emission tomography. This approach gives homogeneous products through site‐specific enzyme‐mediated conjugation and should be broadly applicable to other metal complexes and proteins. 相似文献
55.
The fluid dynamics behavior of shallow fluidized and vibrofluidized beds operating with fresh leaves was investigated with the aim of exploring drying applications in a modified conveyor belt (MCB) system,which may be operated in a fixedor fluidized-bed mode.Leaves of the specimens Duranta repens,Schinus molle,Coleus barbatus,Buxus sempervirens,and Bougainvillea spectabilis were tested with a range of sphericities from 0.063 to 0.213,bulk densities from 0.038 to 0.251 g/cm 3,apparent densities from 0.52 to ... 相似文献
56.
The established, spectral characterisation of bipartite graphs with unweighted vertices (which are here termed homogeneous graphs) is extended to those bipartite graphs (called heterogeneous) in which all of the vertices in one set are weighted h1 , and each of those in the other set of the bigraph is weighted h2. All the eigenvalues of a homogeneous bipartite graph occur in pairs, around zero, while some of the eigenvalues of an arbitrary, heterogeneous graph are paired around (h1 + h2), the remainder having the value h2 (or hl). The well-documented, explicit relations between the eigenvectors belonging to “paired” eigenvalues of homogeneous graphs are extended to relate the components of the eigenvectors associated with each couple of “paired” eigenvalues of the corresponding heterogeneous graph. Details are also given of the relationships between the eigenvectors of an arbitrary, homogeneous, bipartite graph and those of its heterogeneous analogue. 相似文献
57.
[structure: see text]. A total synthesis of acetylcholine blocking agent, phenserine, has been achieved by employing a [4+1] cyclization between an appropriately substituted indole isocyanate and a bis(alkylthio)carbene. 相似文献
58.
Steven?D?Buckingham Luanda?Pym Andrew?K?Jones Laurence?Brown Mark?SP?Sansom David?B?Sattelle Philip?C?BigginEmail author 《BMC neuroscience》2005,6(1):2
Background
Nicotinic acetylcholine receptors (nAChRs) are pentameric proteins that are important drug targets for a variety of diseases including Alzheimer's, schizophrenia and various forms of epilepsy. One of the most intensively studied nAChR subunits in recent years has been α7. This subunit can form functional homomeric pentamers (α7)5, which can make interpretation of physiological and structural data much simpler. The growing amount of structural, pharmacological and physiological data for these receptors indicates the need for a dedicated and accurate database to provide a means to access this information in a coherent manner. 相似文献59.
60.
Determination of the location of coke in catalysts by a novel NMR-based, liquid-porosimetry approach
Gopinathan N Greaves M Lowe JP Wood J Rigby SP 《Journal of colloid and interface science》2012,381(1):164-170
In this work, a new technique, suitable for chemically-heterogeneous materials, has been used to characterise the structural properties of porous heterogeneous catalysts. A liquid-liquid exchange (LLE) process within nanoporous catalysts has been followed using NMR relaxometry and NMR diffusometry. In order to validate the new technique, two model materials were used. First, a chemically-pure, sol-gel silica, with a simple, mono-disperse pore-space, was studied. The second model material was a bidisperse, eggshell Pt-alumina catalyst. The Pt-alumina catalyst was studied both fresh, and coked following chemical reaction. The degree of structural and chemical complexity added by coking was restricted by the localisation of the coke deposition to the Pt-eggshell layer. Under so-called 'metered' supply conditions, when a high affinity liquid (water) displaced a low affinity liquid (cyclohexane) from the sol-gel silica, entrapment of the low affinity liquid was observed which was similar to that observed in mercury porosimetry. In a similar experiment, comparing LLE in fresh and coked samples of the Pt-alumina catalyst pellets, it was found, for the fresh sample, that water initially displaced cyclohexane from a sub-set of the most accessible, smallest pores, as might expected under metered conditions, but this did not occur for coked catalysts. This finding suggested coking had removed some smaller pores located close to the surface of the pellet, in agreement with where the Pt-metal was preferentially located and coking was known to have occurred. 相似文献