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991.
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993.
Hall WP Ngatia SN Van Duyne RP 《The journal of physical chemistry. C, Nanomaterials and interfaces》2011,115(5):1410-1414
A method to amplify the wavelength shift observed from localized surface plasmon resonance (LSPR) bioassays is developed using gold nanoparticle-labeled antibodies. The technique, which involves detecting surface-bound analytes using gold nanoparticle conjugated antibodies, provides a way to enhance LSPR shifts for more sensitive detection of low-concentration analytes. Using the biotin and antibiotin binding pair as a model, we demonstrate up to a 400% amplification of the shift upon antibody binding to analyte. In addition, the antibody-nanoparticle conjugate improves the observed binding constant by 2 orders of magnitude, and the limit of detection by nearly 3 orders of magnitude. This amplification strategy provides a way to improve the sensitivity of plasmon-based bioassays, paving the way for single molecule-based detection and clinically relevant diagnostics. 相似文献
994.
Rachid Touzani Michael HaibachAgnieszka J. Nawara-Hultzsch Sghir El KadiriThomas J. Emge Alan S. Goldman 《Polyhedron》2011,30(15):2530-2534
The complexation of the simple 1-hydroxymethyl-3,5-dimethylpyrazole (HL) ligand with Fe and Ni salts leads to interesting polynuclear complexes in good yield. X-ray diffraction reveals that the resulting complexes (μ4-L)4Ni4Cl4(H2O)4 and (μ2-L)4(μ3-L)2Fe8Cl16(μ4-O)6 adopt cubane-type and open-cubane-type structures in the solid state. 相似文献
995.
Direct measurements of the in-plane London penetration depth λ L have recently been performed on high-temperature superconducting copper oxides by a new low-energy muon spin rotation technique. The results show that λ L is isotope dependent, evidencing unconventional electron–phonon interactions as its source. The data are interpreted here in terms of polaronic effects on the single-particle energies, which leads to level shifts and exponential band narrowing. Good agreement with the experimental data is obtained. 相似文献
996.
997.
Matthew J. Drake David W. Pentico Carl Toews 《Mathematical and Computer Modelling》2011,53(1-2):359-375
While there has been considerable work over the years on multistage lot-sizing models, particularly in an MRP environment, there has been relatively little work on systems recognizing the WIP effects when there is gradual conversion of the components into the final product, as in production planning using the EPQ model for planning the final product. Here we consider lot-sizing planning for a two-stage system in which the final product is planned using an EPQ model with partial backordering and the production of the components is controlled using basic EPQ models without backordering. 相似文献
998.
Dr. Carl Kippenberger 《Analytical and bioanalytical chemistry》1895,34(1):294-346
999.
Cevher Altug Alan K. BurnettEsra Caner Ya?ar DürüstMark C. Elliott Roger P.J. GlanvilleCarol Guy Andrew D. Westwell 《Tetrahedron》2011,67(49):9522-9528
A series of thiazolo[3,2-a]pyridines have been prepared using a multicomponent reaction between aromatic aldehydes, 2-nitromethylenethiazolidine and nitriles containing an active methylene group (malononitrile, ethyl 2-cyanoacetate and 2-phenylsulfonylacetonitrile) in the presence of Et3N under mild conditions with high yields. One of the compounds shows promising anticancer activity across a range of cancer cell lines. 相似文献
1000.
Lise-Lotte Gundersen Carl Henrik G?rbitz Liina Neier Heidi Roggen Toomas Tamm 《Theoretical chemistry accounts》2011,129(3-5):349-358
Density Functional Theory calculations of nine 2-substituted N-methoxy-9-methyl-9H-purin-6-amines in the amino and imino tautomeric forms, as well as the complexes of the same with dimethyl sulfoxide (DMSO), were performed using two functionals (BP86 and B3LYP) and two basis sets (SV(P) and def2-TZVP). Solid-state structures of two of the compounds were obtained from single-crystal X-ray diffraction techniques. It was found that the inclusion of both an explicit hydrogen-bonding partner (DMSO) as well as continuum solvation effects, and vibrational corrections to energy, were necessary for qualitative and reasonable quantitative agreement with observed tautomeric ratios. The solution-optimized geometries and X-ray structures were found to be in good agreement. NMR spectroscopy confirmed the dependence of the tautomeric ratios on hydrogen-bonding abilities, in addition to the dipole moment of the solvent in question. Natural Bond Orbital charges on the N-7 nitrogen, as well as the tautomeric ratios were used to explain the observed reactivities of the compounds toward N-7 alkylation. 相似文献