Search results for "Biomaterial"
showing 10 items of 1350 documents
A set-up for simultaneous measurement of second harmonic generation and streaming potential and some test applications.
2018
We present a measurement cell that allows simultaneous measurement of second harmonic generation (SHG) and streaming potential (SP) at mineral-water interfaces with flat specimen that are suitable for non-linear optical (NLO) studies. The set-up directly yields SHG data for the interface of interest and can also be used to obtain information concerning the influence of flow on NLO signals from that interface. The streaming potential is at present measured against a reference substrate (PTFE). The properties of this inert reference can be independently determined for the same conditions. With the new cell, for the first time the SHG signal and the SP for flat surfaces have been simultaneousl…
Influence of theZ/EIsomerism on the Pathway Complexity of a Squaramide‐Based Macrocycle
2020
The rising interest on pathway complexity in supramolecular polymerization has prompted the finding of novel monomer designs able to stabilize kinetically trapped species and generate supramolecular polymorphs. In the present work, the exploitation of the Z/E (geometrical) isomerism of squaramide (SQ) units to produce various self-assembled isoforms and complex supramolecular polymerization pathways in methylcyclohexane/CHCl3 mixtures is reported for the first time. This is achieved by using a new bissquaramidic macrocycle (MSq) that self-assembles into two markedly different thermodynamic aggregates, AggA (discrete cyclic structures) and AggB (fibrillar structures), depending on the solven…
Carbohydrate-supramolecular gels : adsorbents for chromium(VI) removal from wastewater.
2019
Abstract Hypothesis To overcome the contamination of water by heavy metals the adsorption of the pollutant on gel phases is an attractive solution since gels are inexpensive, potentially highly efficient and form a distinct phase while allowing diffusion of the contaminated water throughout the material. This work tests the chromium(VI) adsorbent capacity of new supramolecular gels for Chromium(VI) removal from wastewater. Experiments First hydrophobic imidazolium salts of carbohydrate anions were synthesised as new gelators. Subsequently, they were dissolved in a solvent by heating and, after cooling overnight, to give the formation of supramolecular gels. The properties of the resulting g…
Method of Discrimination of Surface Fractality
1993
Abstract A simple method for the discrimination of surface fractality is proposed. This method is based on the comparison of the nitrogen adsorption isotherm on a given sample with the "standard" isotherm on a smooth surface. The proposed comparative method makes it possible to determine the lower limit of the scale range of surface fractality. A thermodynamic method is recommended as a complement to fractal analysis in the scale range of about 10-1000 A. The results of the investigation of surface roughness are presented with examples of typical samples of silica gels, porous glasses, apatite, and coal.
Experimental and theoretical evidence of overcharging of calcium silicate hydrate
2007
International audience; Electrokinetic measurements such as electrophoresis may show an inversion of the effective surface charge of colloidal particle called overcharging. This phenomenon has been studied by various theoretical approaches but up to now very few attempts of confrontation between theory and experiment have been conducted. In this work we report electrophoretic measurements as well as Monte Carlo simulations of the electrokinetic potential for the surface of calcium silicate hydrate (Csingle bondSsingle bondH), which is the major constituent of hydrated cement. In the simulations, the surface charge of Csingle bondSsingle bondH nanoparticles in equilibrium with the ionic solu…
Printing Life-Inspired Subcellular Scale Compartments with Autonomous Molecularly Crowded Confinement.
2019
A simple, rapid, and highly controlled platform to prepare life-inspired subcellular scale compartments by inkjet printing has been developed. These compartments consist of fL-scale aqueous droplets (few µm in diameter) incorporating biologically relevant molecular entities with programmed composition and concentration. These droplets are ink-jetted in nL mineral oil drop arrays allowing for lab-on-chip studies by fluorescence microscopy and fluorescence life time imaging. Once formed, fL-droplets are stable for several hours, thus giving the possibility of readily analyze molecular reactions and their kinetics and to verify molecular behavior and intermolecular interactions. Here, this pla…
Influence of the electrical interface properties on the rheological behavior of sonicated soy lecithin dispersions
2006
A significant effect, on the rheological behavior, due to the electrical properties of vesicles formed from concentrated soy lecithin dispersions have been studied in this work. The rheopectic behavior of concentrated soy lecithin dispersions (120, 150, 180, 210 and 240 g L−1) prepared by swelling–light sonication–freezing–unfreezing procedure is studied and it is specially emphasized on the transition under steady shear from lamellar phase of planar sheets to closed structures as multilamellar vesicles. Samples have been exposed to a different number of sonication cycles (from 0 to 100) and the changes in the hysteresis loop area, the apparent viscosity and the electrophoretic mobility hav…
A New Prosthetic Implant for Inguinal Hernia Repair: Its Features in a Porcine Experimental Model
2011
Even after more than 100 years of inguinal hernia repair, the rate of complications and recurrence remains unacceptably high. In the last decades, few effective advances in surgical technique and materials have been made. The authors see them as minor adjustments in the shape and materials of the prosthetic implants. Still, the underlying genesis of inguinal hernia remains undefined. Based upon this, it seems the surgical repair of inguinal protrusions cannot be based upon the pathogenesis because the etiology to date has not been addressed. Most hernia repairs are performed with some degree of point fixation (sutures/tacks) to stop the mesh from migrating and creating high recurrence rates…
The effect of detergents on the basement membrane complex of a biologic scaffold material
2013
The basement membrane complex (BMC) is a critical component of the extracellular matrix (ECM) that supports and facilitates the growth of cells. This study investigates four detergents commonly used in the process of tissue decellularization and their effect upon the BMC. The BMC of porcine urinary bladder was subjected to 3% Triton-X 100, 8 mM 3-[(3-cholamidopropyl) dimethylammonio]-1-propanesulfonate (CHAPS), 4% sodium deoxycholate or 1% sodium dodecyl sulfate (SDS) for 24 h. The BMC structure for each treatment group was assessed by immunolabeling, scanning electron microscopy (SEM) and second harmonic generation (SHG) imaging of the fiber network. The composition was assessed by quantif…
Composite Material Recycling Technology – State-of-the-Art and Sustainable Development for the 2020s.
2020
Recently, significant events took place that added immensely to the sociotechnical pressure for developing sustainable composite recycling solutions, namely (1) a ban on composite landfilling in Germany in 2009, (2) the first major wave of composite wind turbines reaching their End-of-Life (EoL) and being decommissioned in 2019–2020, (3) the acceleration of aircraft decommissioning due to the COVID-19 pandemic, and (4) the increase of composites in mass production cars, thanks to the development of high volume technologies based on thermoplastic composites. Such sociotechnical pressure will only grow in the upcoming decade of 2020s as other countries are to follow Germany by limiting and ba…