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colloids for nano- and biotechnology

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[...]... b X-ray diffraction patterns for unseeded C16 thin layers dried at 20 ◦ C and thermally treated at 450 ◦ C c N2 adsorption–desorption isotherms of a calcined unseeded C16 thin layer 6 A Ayral Fig 9 SEM cross-section image (a) and TEM image for a P70 layer (b); Rejection rates R% versus PEG molecular weight for P70 and F67 membranes for unseeded and seeded membranes C16 and C12 The measured permeance... position shifts to smaller values of the scattering vector q, and progressively vanishes Osmotic swelling pressure measurements show that Ca ions reduce the swelling pressure and Introduction Colloids, polymers and biomaterials are increasingly important, from both fundamental and applied viewpoints The demand for materials with controlled structure and morphology at all dimensions from nanoscale to macroscale... in the range of the deformation ratio 0.7 < Λ < 1 The data were analyzed using the relation [2] σ = G Λ − Λ−2 , (5) where G is the shear modulus and σ is the nominal stress (related to the undeformed cross-section of the gel cylinder) The absence of volume change and barrel distortion was checked by measuring the dimensions of the deformed and undeformed gel cylinders Results and Discussion Fig 1 SANS... enables molecular and nanometer scale manipulation with the aim of engineering useful and novel properties Examples of applications include responsive biomaterials in tissue repair, e.g., “smart hydrogel scaffolds” for tissue engineering, medical implants for diagnosis and therapy, and in-vivo drug-delivery The main focus of our research is on the roles that nanoscale structures and interactions play... overall performance of membranes is related to two main characteristics of such separative layers, their permeability and their permselectivity (separation ability) For porous membranes, the selectivity and the membrane cut-off depend on the pore size and on the pore size distribution of the separative layer In the case of the smallest pores (mesopores and micropores) the developed area is very large and. .. interactions and architecture Biological systems operate at the cellular and subcellular levels; therefore, material properties including structure, osmotic and mechanical properties must be determined to dimensions below 100 nm An emerging area of practical significance relates to biomimetic polymer networks and gels Recently designed synthetic polymers mimic the hierarchical structure and function... elemental bricks Preparation of the sol before deposition Size, shape, size distribution Conditions of polymerization/destabilization Sol aging Thermal aging Chemical post treatments Freeze-drying, hypercritical drying, Reinforcement after deposition and before drying Drying method 4 Fig 3 Pore size distributions for sol–gel derived layers Mesophase Templating and Ordered Mesoporosity Extension of the... and membranes of oxides like Al2 O3 and TiO2 (Fig 6) [25–29] Mesoporous Silica Membranes 2D and 3D hexagonal mesoporous silica membranes were successfully prepared according to the synthesis procedures reported in [30, 31] Only the 2D hexagonal membranes shown in Fig 7 will be discussed here These 5 Fig 8 Nitrogen permeance versus applied pressure difference for unseeded and seeded membranes, C16 and. .. B, C and m are constants C is mostly due to incoherent “background” scattering, which is independent of q The dashed lines show the fits of Eq 6 to the SANS spectra For small ˚ values of q (< 0.01 A−1 ) both DNA and PAA gels exhibit a power law behavior with a slope −3.4 < m < −4, that can be attributed to scattering from interfaces Rough colloids give slopes between −3 and −4, whereas smooth colloids. .. (cross-section of the DNA molecule) remains unchanged Osmotic Pressure and Shear Modulus Measurements In this section we focus on the macroscopic elastic and osmotic properties of PAA and DNA gels, and relate the macroscopic behavior to structural features identified by SANS The dependence of the swelling degree (1/ϕ) on the CaCl2 concentration for DNA and PAA gels swollen in 10 mM NaCl solution is plotted in Fig . Steinen-Broo, Pau/Girona, Spain Typesetting and production: le-tex publishing services oHG, Leipzig Printed on acid-free paper Progr Colloid Polym Sci (2008) 135: V © Springer-Verlag 2008 Preface Over. w0 h0" alt="" Progress in Colloid and Polymer Science · Volume 135 · 2008 Progress in Colloid and Polymer Science Recently Published and Forthcoming Volumes Colloids for Nano- and Biotechnology Volume. fascinat- ing approaches to increase or manage the permeability of ceramic membranes. This paper presents a short review of approaches developed in our laboratory for the prep- aration of innovative porous

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