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91.
The objective of this study was to investigate the behavior of large plasmids on the monolithic columns under binding and nonbinding conditions. The pressure drop measurements under nonbinding conditions demonstrated that the flow velocities under which plasmid passing monolith became hindered by the monolithic pore structure depended on the plasmid size as well as on the average monolith pore size; however, they were all very high exceeding the values encountered when applying CIM monolithic columns at their maximal flow rate. The impact of the ligand density and the salt concentration in loading buffer on binding capacity of the monolith for different sized plasmids was examined. For all plasmids the increase of dynamic binding capacity with the increase of salt concentration in the loading solution was observed reaching maximum of 7.1 mg/mL at 0.4M NaCl for 21 kbp, 12.0 mg/mL at 0.4 M NaCl for 39.4 kbp and 8.4 mg/mL at 0.5M NaCl for 62.1 kbp. Analysis of the pressure drop data measured on the monolithic column during plasmid loading revealed different patterns of plasmid binding to the surface, showing "car-parking problem" phenomena under certain conditions. In addition, layer thickness of adsorbed plasmid was estimated and at maximal dynamic binding capacity it matched calculated plasmid radius of gyration. Finally, it was found that the adsorbed plasmid layer acts similarly as the grafted layer responding to changes in solution's ionic strength as well as mobile phase flow rate and that the density of plasmid layer depends on the plasmid size and also loading conditions. 相似文献
92.
Binding of three different bacteriophages (phages), namely T7, lambda and M13 on methacrylate monoliths was investigated. Phage M13 exhibited the highest dynamic binding capacity of 4.5×10(13) pfu/mL while T7 and lambda showed capacity of 1×10(13) pfu/mL, all corresponding to values of around 1mg/mL. Interestingly, capacity for lambda phage was increased 5-fold by increasing NaCl concentration in a loaded sample from 0 to 0.2M while there was a constant capacity decrease for T7 and M13 phages. Under optimal conditions, recovery for all three phages approached 100%. Measurement of a pressure drop increase during loading enabled estimation of adsorbed phage layer thickness. At a maximal capacity it was calculated to be around 50 nm for T7 phage and 60 nm for lambda phage matching closely capside size thus indicating monolayer adsorption while 80 nm layer thickness was estimated for M13 phage showing its orientation along the pore. 相似文献
93.
Jorge Francés Sergio Bleda Sergi Gallego Cristian Neipp Andrés Márquez Inmaculada Pascual Augusto Beléndez 《Physics letters. A》2013,377(34-36):2245-2250
A set of simplified and rigorous electromagnetic vector theories is used for analyzing the transmittance characteristics of diffraction phase gratings. The scalar diffraction theory and the effective medium theory are validated with the exact results obtained via the rigorous coupled-wave theory and the finite-difference time-domain method. The effects of surface profile parameters and also the angle of incidence is demonstrated to be a limiting factor in the accuracy of these theories. Therefore, the error of both simplified theories is also analyzed in non-paraxial domain with the intention of establishing a specific range of validity for both simplified theories. 相似文献
94.
David Servera‐Francés Francisco Arteaga‐Moreno Irene Gil‐Saura Martina G. Gallarza 《商业与工业应用随机模型》2013,29(3):241-253
A modern approach to logistics allows it to be understood and used for its capacity to generate value, because value is managerially important as a strategic objective for any firm. In the present work a particular view of this approach is offered by providing a structural model where logistics service quality and sacrifices contribute to the formation of logistics value, but where service quality is also an important determinant of satisfaction. This combined approach, tested with multiblock partial least‐sqaures path modelling, in the particular setting of a business‐to‐business encounter, provides empirical support for a chain of effects between service quality–logistics value–satisfaction–loyalty without underestimating the important effect of service quality on satisfaction and satisfaction on loyalty in industrial settings. This proposed conceptual model of the relationship between customer loyalty and the various contributing factors to that loyalty is the main contribution in this paper. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
95.
96.
We prove that every bordered Riemann surface admits a complete proper holomorphic immersion into a ball of $\mathbb C ^2$ , and a complete proper holomorphic embedding into a ball of $\mathbb C ^3$ . 相似文献
97.
Domen Stadler Franc Kosel Damjan Čelič Andrej Lipej 《International Journal of Computational Fluid Dynamics》2013,27(8):439-448
In the article a new mesh deformation algorithm based on artificial neural networks is introduced. This method is a point-to-point method, meaning that it does not use connectivity information for calculation of the mesh deformation. Two already known point-to-point methods, based on interpolation techniques, are also presented. In contrast to the two known interpolation methods, the new method does not require a summation over all boundary nodes for one displacement calculation. The consequence of this fact is a shorter computational time of mesh deformation, which is proven by different deformation tests. The quality of the deformed meshes with all three deformation methods was also compared. Finally, the generated and the deformed three-dimensional meshes were used in the computational fluid dynamics numerical analysis of a Francis water turbine. A comparison of the analysis results was made to prove the applicability of the new method in every day computation. 相似文献
98.
Claudia Cordes Massimiliano Morganti Iris Klawitter Claudia Schremmer Sebastian Dechert Franc Meyer 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(32):10971-10974
μ‐Oxodiiron(III) species are air‐stable and unreactive products of autoxidation processes of monomeric heme and non‐heme iron(II) complexes. Now, the organometallic [(LNHC)FeIII‐(μ‐O)‐FeIII(LNHC)]4+ complex 1 (LNHC is a macrocyclic tetracarbene) is shown to be reactive in C?H activation without addition of further oxidants. Studying the oxidation of dihydroanthracene, it was found that 1 thermally disproportionates in MeCN solution into its oxoiron(IV) ( 2 ) and iron(II) components; the former is the active species in the observed oxidation processes. Possible cleavage scenarios for 1 are shown by scrambling experiments and structural characterization of an unprecedented adduct of 1 and oxoiron(IV) complex 2 . Kinetic analysis gave an equilibrium constant for the disproportionation of 1 , which is very small (Keq=7.5±2.5×10?8 m ). Increasing Keq might by a useful strategy for circumventing the formation of dead‐end μ‐oxodiiron(III) products during Fe‐based homogeneous oxidation catalysis. 相似文献
99.
100.
ArpadBURMEN FrancBRATKOVIC JanezPUHAN IztokFAJFAR TadejTUMA 《数学学报(英文版)》2004,20(3):433-440
An extension of the global convergence framework for unconstrained derivative-free optimization methods is presented. The extension makes it possible for the framework to include optimization methods with varying cardinality of the ordered direction set. Grid-based search methods are shown to be a special case of the more general extended global convergence framework. Furthermore,the required properties of the sequence of ordered direction sets listed in the definition of grid-based methods are relaxed and simplified by removing the requirement of structural equivalence. 相似文献