Core/shell sphere

Figure 3 Example of SANS curves at two times of the reaction. The lines are calculations of the form factor. (A) prior to TEOS addition, the micelles are well described by core-shell spheres, with an external radius of 7.1 ran. ( ) 15 minutes after the beginning of the reaction, the micelles can be viewed as cylinders of length 50 nm and radius 6.9 nm.

Fig. 4 Formation of a core-shell sphere upon heating an aqueous PNIPAM-g-...

Theoretical Feasibility. Earlier work (5) had established the general domain of size parameters and refractive index expected. This allowed a number of model calculations to be carried out to clearly establish the theoretical feasibility of the method. Computations were carried out for homogeneous spheres and for concentric core-shell spheres. 

Fig. 4 Formation of a core-shell sphere upon heating an aqueous PNlPAM-g-poly(ethylene oxide) (PBO) copolymer solution black PNIPAM backbone and grey PEO grafts. LCST lower critical solution temperature [170]...

In the following the isoscattering point shall be discussed for a monodisperse core-shell sphere. The radial electron density profile is displayed in Fig. 1. There is a shell of three nanometers thickness in which the electron density is increased by 20 electrons /nm. ... 

Fig. 4. Isoscattering point for a system of polydisperse core-shell spheres. A Gaussian size distribution with a standard deviation of 9% has been assumed for the cores whereas the thickness of the shell was kept constant. The inset gives the contrast p - Pm (electrons/nm ). The uppermost curve refers to homogeneous spheres with diameter 37 nm. The dashed line marks the isoscattering point which coincides with the minimum of the form factor of the homogeneous sphere...

Equqtion (51.15) provides the extinction cross section for spherical particles in a dielectric medium. When the particles are coated by a surface layer, the optical properties of both the core and shell materials must be considered. The extinction cross section of a concentric core-shell sphere is given by [144],... 

The spray head configuration is an interesting aspect of EHDA. The nozzle varies from a simple hypodermic needle of different diameters to highly technologically advanced multiplex nozzles (Figure 22.8). The coaxial needle shown increases the number of centered nozzles to four and is mainly used to fabricate multilayer spheres. In coaxial setups, the most commonly used is the coaxial two-capillary nozzle used to fabricate core-shell spheres (capsules). The inner needle is supplied by a solution of active substance and the outer needle is filled with shell material.In this process, parameters are used as adjusting switches to control the diameter of the capsules, thickness of the shell, and number of inner cores. The two solvents used in the coaxial setup are immiscible and wettable, and the inner one has a higher surface tension. 

Fig. 11 (A) SEM image of the synthesized Ag sphere (B) SEM image of Ag/AgCl core-shell spher) and (C) Photocatalytic activities for the degradation of RhB dye under visible-lightirradiation U >420 nm) without catalyst (a) and over various Ag/AgCl core-shell spheres with different molar ratios of Fe Ag (1 10 (b), 1 5 (c), 1 2 (d), 1 3 (e), 1 4 (f), 1 1 (g) and 2 1 (h)). Reproduced from ref. 12. Copyright (2013), with permission from Elsevier.

With increasing amoimt of triblock copolymer, blends of lamellar SBT triblock copolymers with the asymmetric SB diblock copolymer form core-shell spheres, core-shell cylinders, core-shell double gyroids, and lamellae (Fig. 34). T forms the core domains in these morphologies, which can be considered as coreshell analogues of the well-known diblock copolymer morphologies (76). 

Fig. 2.2 Assemblies fonned in selective solvent conditions by multiblock copol3nners (from upper left to right) Janus spheres, core-shell spheres, raspberry-like spheres, Janus cylinders, core-shell cylinders, segmented cylinders, asymmetric (Janus) membrane vesicles, double-layer membrane vesicles, vesicles with hexagonally packed cylinders. Reproduced from [3] with permission from Elsevier...

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