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61.
Versatile Synthetic Strategy for Coating Upconverting Nanoparticles with Polymer Shells through Localized Photopolymerization by Using the Particles as Internal Light Sources 下载免费PDF全文
Selim Beyazit Dr. Serena Ambrosini Dr. Nataliya Marchyk Emilia Palo Vishal Kale Prof. Tero Soukka Dr. Bernadette Tse Sum Bui Prof. Karsten Haupt 《Angewandte Chemie (International ed. in English)》2014,53(34):8919-8923
We present a straightforward and generic strategy for coating upconverting nanoparticles (UCPs) with polymer shells for their protection, functionalization, conjugation, and for biocompatibility. UCPs are attracting much attention for their potential use as fluorescent labels in biological applications. However, they are hydrophobic and non‐compatible with aqueous media; thus prior surface modification is essential. Our method uses the internal UV or visible light emitted from UCPs upon photoexcitation with near‐infrared radiation, to locally photopolymerize a thin polymer shell around the UCPs. In this way, a large variety of monomers with different chemical functionalities can be incorporated. If required, a second layer can be added on top of the first. Our method can provide a large spectrum of surface functional groups rapidly and in one pot, hence offering a platform for the preparation of libraries of functional polymer‐encapsulated UCPs for applications in bioassays, biosensing, optical imaging, and theranostics. 相似文献
62.
F. Lestremau M.-E. Willemin C. Chatellier S. Desmots C. Brochot 《Analytical and bioanalytical chemistry》2014,406(14):3477-3487
An analytical method was developed to measure cis-permethrin and trans-permethrin in different biological rat matrices and fluids (whole blood, red blood cells, plasma, brain, liver, muscle, testes, kidneys, fat and faeces). The method was also suitable for the simultaneous quantification of their associated metabolites [cis-3-(2,2-dichlorovinyl)-2,2-dimethyl-(1-cyclopropane) carboxylic acid (cis-DCCA), trans-3-(2,2-dichlorovinyl)-2,2-dimethyl-(1-cyclopropane) carboxylic acid (trans-DCCA) and 3-phenoxybenzoic acid (3-PBA)] in blood (whole blood, red blood cells, plasma) and liver. The target analytes were derivatised in samples using a methanolic/hydrochloric acid solution and then extracted with toluene. The analysis was performed by gas chromatography, and detection using ion trap tandem mass spectrometry. The selectivity obtained for complex matrices such as rat organs allowed the use of a purification step to be avoided for most of the matrices investigated. In the case of fat, where permethrin is suspected to accumulate, a dedicated purification step was developed. In fluids, the limits of quantification were at the 50 ng/mL level for the parent compounds and 3-PBA and at 25 ng/mL for cis-DCCA and trans-DCCA. For solid matrices excluding fat, the limits of quantification ranged from 50 ng/g for muscle to 100 ng/g for brain and testes for both cis-permethrin and trans-permethrin. The extraction recoveries ranged primarily between 80 and 120 % for the matrix tested. The stability of blood samples was tested through the addition of 1 % v/v formic acid. The methods developed were applied in a toxicokinetic study in adult rats. cis-Permethrin and the metabolites were detected in all corresponding matrices, whereas trans-permethrin was detected only in blood, plasma and faeces. 相似文献
63.
Wu Bei Maya Brenda Ivette Garcia Limnios Nikolaos 《Methodology and Computing in Applied Probability》2021,23(4):1433-1434
Methodology and Computing in Applied Probability - The original version of this article contained mistakes, and the author would like to correct them. 相似文献
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65.
The theoretical shape of the D.S.C. or D.T.A. thermograms for the melting of binary solutions has been determined from the basic equations of the corresponding calorimeters. The case of binary solutions with immiscible solid phases or with solid solutions is examined. 相似文献
66.
Danièle CLAUSSE Isabelle PEZRON Amélie BEHAEGHEL 《Journal of Dispersion Science and Technology》2013,34(1-2):315-326
Water transfer between water droplets and water + NaCl droplets dispersed within emulsions have been pointed out by differential scanning calorimetry. Using a solution- diffusion model, water fluxes have been calculated. 相似文献
67.
M. Deschatre F. Ghillebaert J. Guezennec C. Simon Colin 《Applied biochemistry and biotechnology》2013,171(6):1313-1327
Metal remediation was studied by the sorption of analytical grade copper Cu(II) and silver Ag(I) by four exopolysaccharides (EPS) produced by marine bacteria. Colorimetric analysis showed that these EPS were composed of neutral sugars, uronic acids (>20 %), acetate, and sulfate (29 %). Metal sorption experiments were conducted in batch process. Results showed that the maximum sorption capacities calculated according to Langmuir model were 400 mg g?1 EPS (6.29 mmol g?1) and 333 mg g?1 EPS (3.09 mmol g?1) for Cu(II) and Ag(I), respectively. Optimum pH values of Ag(I) sorption were determined as 5.7. Experiment results also demonstrated the influence of initial silver concentration and EPS concentrations. Microanalyzing coupled with scanning electron microscopy demonstrated the presence of metal and morphological changes of the EPS by the sorption of metallic cations. The Fourier transform infrared spectroscopy analysis indicated possible functional groups (e.g., carboxyl, hydroxyl, and sulfate) of EPS involved in the metal sorption processes. These results showed that EPS from marine bacteria are very promising for copper and silver remediation. Further development in dynamic and continuous process at the industrial scale will be established next. 相似文献
68.
Yunhui Hou Nikolaos Limnios Walter Schön 《Methodology and Computing in Applied Probability》2017,19(4):1241-1250
In this paper, we study the existence and uniqueness of the solution for Markov renewal equation (MRE) of a semi-Markov process with countable state space. This method and its proof are based on an iterative scheme. A numerical solution is also given as well as a case study on system reliability assessment. 相似文献
69.
A novel implicit immersed boundary method of high accuracy and efficiency is presented for the simulation of incompressible viscous flow over complex stationary or moving solid boundaries. A boundary force is often introduced in many immersed boundary methods to mimic the presence of solid boundary, such that the overall simulation can be performed on a simple Cartesian grid. The current method inherits this idea and considers the boundary force as a Lagrange multiplier to enforce the no‐slip constraint at the solid boundary, instead of applying constitutional relations for rigid bodies. Hence excessive constraint on the time step is circumvented, and the time step only depends on the discretization of fluid Navier‐Stokes equations, like the CFL condition in present work. To determine the boundary force, an additional moving force equation is derived. The dimension of this derived system is proportional to the number of Lagrangian points describing the solid boundaries, which makes the method very suitable for moving boundary problems since the time for matrix update and system solving is not significant. The force coefficient matrix is made symmetric and positive definite so that the conjugate gradient method can solve the system quickly. The proposed immersed boundary method is incorporated into the fluid solver with a second‐order accurate projection method as a plug‐in. The overall scheme is handled under an efficient fractional step framework, namely, prediction, forcing, and projection. Various simulations are performed to validate current method, and the results compare well with previous experimental and numerical studies. 相似文献
70.
Marcela Cruchaga Diego Celentano Piotr Breitkopf Pierre Villon Alain Rassineux 《国际流体数值方法杂志》2010,63(4):415-430
Classical Lagrangian schemes applied to update the front position between two immiscible incompressible fluids have been long recognized to provide a sharp representation of the interface. However, the main drawback of these approaches is the progressive distortion in the distribution of the markers used to identify the material front. To avoid this problem, a 3D interface remeshing algorithm is proposed in this work. In addition, the remeshed front is enforced to preserve the global volume. These aspects are incorporated in an existing fluid dynamics formulation for the analysis of two‐fluid flows problems. The resulting formulation, called as the 3D‐moving Lagrangian interface remeshing technique, is applied in the numerical analysis of two‐fluid flow problems. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献