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811.
In order to simplify the procedure for assembling a surface-plasmon resonance (SPR) sensor, a refractive index matching polymer film was prepared as an alternative to the conventionally used matching oil. The refractive index matching polymer film, the refractive index of which was nearly equal to the prism and sensor chip material (a cover glass) of the SPR sensor, was prepared by casting a tetrahydrofuran solution of poly (vinyl chloride) (PVC) containing equal weights of dioctyl phthalate and tricresyl phosphate. The refractive index matching polymer film was found to have a refractive index of 1.516, which is identical to that of the prism and the cover glass used for the present SPR sensor. The utility of the matching polymer film for the SPR sensor was confirmed by the detection of anti-human albumin, based on an antigen-antibody reaction.  相似文献   
812.
Merging cooperative Si-H bond activation and electrophilic aromatic substitution paves the way for C-3-selective indole C-H functionalization under electronic and not conventional steric control. The Si-H bond is heterolytically split by the Ru-S bond of a coordinatively unsaturated cationic ruthenium(II) complex, forming a sulfur-stabilized silicon electrophile. The Wheland intermediate of the subsequent Friedel-Crafts-type process is assumed to be deprotonated by the sulfur atom, no added base required. The overall catalysis proceeds without solvent at low temperature, only liberating dihydrogen.  相似文献   
813.
814.
Oxygen plasma-assisted molecular beam epitaxial (MBE) growth of Pr1−xSrxMnO3 (PSMO) thin films has been carried out on NdGaO3(1 1 0) (NGO) substrates. The growth parameters have been optimized to realize 2D layer-by-layer growth. XRD results of the epilayers show that the PSMO/NGO(1 1 0) thin films are of high crystal quality, as clear diffraction peaks can be observed belonging to the film and the substrate, respectively. Based on analysis of the peaks, it was concluded that epitaxial relation is PSMO(1 1 0)//NGO(1 1 0), i.e., the c-axis being parallel to the surface. Both single scans (ω scan, 2θ/ω scan) and 2-axis reciprocal space mapping (RSM) were performed in an effort to assess the crystal structure, crystalline quality, surface and interface properties of the epitaxial layers. High temperature annealing effects on lattice structure and crystal quality have been studied and discussed. Transport property measurement of the PSMO thin film samples has been carried out and main features discussed.  相似文献   
815.
Minimum edge ranking spanning trees of split graphs   总被引:1,自引:0,他引:1  
Given a graph G, the minimum edge ranking spanning tree problem (MERST) is to find a spanning tree of G whose edge ranking is minimum. However, this problem is known to be NP-hard for general graphs. In this paper, we show that the problem MERST has a polynomial time algorithm for split graphs, which have useful applications in practice. The result is also significant in the sense that this is a first non-trivial graph class for which the problem MERST is found to be polynomially solvable. We also show that the problem MERST for threshold graphs can be solved in linear time, where threshold graphs are known to be split.  相似文献   
816.
817.
818.
Polymeric micelles (Lactosome) in the size of 20–30 nm were labeled with radionuclides of 111In (111In-DOTA-Lactosome) for SPECT imaging and 90Y (90Y-DOTA-Lactosome) for β-ray irradiation for mammary tumor in mice. The tumor site at the femoral right leg grafted with 4T1 cells was clearly imaged at 24 h after the intravenous injection. Biodistribution revealed that the half-life time of 111In-DOTA-Lactosome was 11 h, which enabled the nanoparticle selectively accumulated in tumor site due to the enhanced permeability and retention (EPR) effect. The anti-tumor therapeutic effect of 90Y-DOTA-Lactosome was observed depending on the dose frequency and amount. Under the condition of the percutaneous ethanol injection treatment, the therapeutic effect of 90Y-DOTA-Lactosome was enhanced due to the super EPR effect. Owing to the super EPR effect, co-administration of 90Y-DOTA-Lactosome and DOXIL® inhibited the tumor growth during 15 days with their administrations.  相似文献   
819.
A direct asymmetric alkynylation of ketones with new chiral CCN Rh catalysts containing N‐heterocyclic carbene and oxazoline hybrid ligands is described. The catalytic reaction of fluoroalkyl‐substituted ketones, ArCOCF2X (X=F, Cl, H), with aromatic and aliphatic alkynes yielded the corresponding chiral propargyl alcohols with high enantioselectivity. Control and kinetic experiments suggested a bis(alkynyl) Rh intermediate as the active species for the C?C bond‐forming step.  相似文献   
820.
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