Search results for "encapsulation"
showing 10 items of 92 documents
Encapsulació lèxica i avaluació en el debat parlamentari
2018
Lexical encapsulation consists of a series of abstract unspecific nouns (fact, plan...) referring to predicative antecedents. This study is based on a corpus of parliamentary debate in English, Catalan and Spanish (PD) and deals with encapsulation as a complex lexical cohesion device which allows the addressor to evaluate the information of the debates in various ways. Our work tries to highlight the role of lexical encapsulation to reflect the addressor’s positioning with respect to the topic discussed, and to establish whether there are outstanding cross-linguistic differences. In order to delimit the diverse evaluative strategies, an approach from the perspective of prototype theory is a…
Enzymatic cross-linking of pea proteins to produce microparticles : application to the encapsulation of riboflavin
2015
In this work, pea proteins behavior toward enzymatic gelation by microbial transglutaminase (MTGase) was studied at native state and after denaturation (chemical reduction or thermal denaturation). The final application was the formation of protein microparticules to encapsulate riboflavin, chosen as hydrophilic active molecule model. The extraction process of the pea protein fractions has been optimized in such a way to minimize as possible protein denaturation and recover native fractions rich in albumin (Alb) and globulin (Glob) or a mixture of both.The setting up of the enzymatic reaction monitoring methods has brought out their complementarity as well as their limits. Two new monitorin…
Synthesis of low density foam shells for inertial confinement fusion experiments
2011
This work deals with the fabrication process of low density foam shells and the sharp control of their shape (diameter, thickness, density, sphericity, non-concentricity). During this PhD we focused on the non-concentricity criterion which has to be lower than 1%. The shells are synthesized using a microencapsulation process leading to a double emulsion and followed by a thermal polymerization at 60°C. According to the literature, three major parameters, the density of the three phases, the deformations of the shells along the process and the kinetics of the polymerization have a direct influence on the shells non-concentricity. The results obtained showed that when the density gap between …
Leach-Proof Sol–Gel Microcapsules as Curing Agents for One-Pot Thermosetting Resins
2013
The sol-gel microencapsulation of free-radical initiator benzoyl peroxide in sol-gel methyl-modified silica microcapsules of core/shell geometry allows curing of acrylate-based polyurethane and polyester resin formulations sprayed from a pressurized can without the need to compartmentalize reactants from the initiator to cross-link. These results open the route to widespread application of sol-gel microcapsules to efficiently cure polymer and composite mixtures that are widely used as functional coatings, molding compounds, adhesives, and sealants.
Microencapsulation of Phenolic Extracts from Cocoa Shells to Enrich Chocolate Bars
2021
AbstractCocoa bean shells were subjected to green extraction technologies, based on the absence of toxic organic solvents, to recover polyphenols; the extract was then encapsulated using a spray dryer and maltodextrin as coating agent. The best conditions observed in the spray drying tests (core-to-coating ratio 1:5; inlet temperature 150 °C; flow rate 6 ml min−1) were applied to produce the microcapsules used to enrich the same cocoa mass as the shells and processed for the preparation of the chocolate bars. Sensory analysis showed no significant differences between enriched chocolate bar and the unenriched reference one, except for the appearance. Both samples were then subjected to accel…
Pentafluoroethylation of Carbonyl Compounds by HFC-125 via the Encapsulation of the K Cation with Glymes
2021
A simple protocol to overcome the explosive pentafluoroethylation of carbonyl compounds by HFC-125 is described. The use of potassium (K) bases with triglyme or tetraglyme as a solvent safely yield...
Preliminary research on conversion of encapsulated somatic embryos of Citrus reticulata Blanco, cv. Mandardino Tardivo di Ciaculli.
2006
Somatic embryogenesis was obtained through anther culture of Citrus reticulata, cv. Mandarino Tardivo di Ciaculli. The work was carried out to evaluate the response of somatic embryos inside a sodium alginate coating to different storage periods, and to the effects of the germicide PPM (1 ml l(-1) stop) and the fungicide Thiophanate-methyl (100 mg l(-1) stop). The effect of these alone or in combination, added to the artificial endosperm on the performance of the encapsulated somatic embryos was tested. After 45 days of culturing, sprouting, root development and conversion were recorded. The encapsulated somatic embryos can be conveniently stored at 4 degrees C, but not for a period longer …
endo-Functionalized molecular tubes : selective encapsulation of neutral molecules in non-polar media
2016
Four endo-functionalized molecular tubes with urea/thiourea groups in the deep cavities have been synthesized, and their binding ability to neutral molecules studied. Very high binding affinity and selectivity have been achieved, which are rationalized by invoking the shape and electrostatic complementarity and dipole alignment.
Nouvelles stratégies de stabilisation des bactéries extrêmement sensibles à l’oxygène : cas du probiotique Faecalibacterium prausnitzii.
2016
Intestinal bacteria are of growing interest in the areas of health and wellness [1, 3]. The intestinal ecosystem is characterized by its complex composi-tion and its very low oxygen content. Therefore, nu-merous bacterial species isolated from this environ-ment are extremely sensitive to oxygen. This feature is responsible for the difficulty of implementation of these microorganisms for probiotic large-scale appli-cations, particularly during processing and storage. In this presentation, we present the main steps that have been overcome to conserve and design a stabilization strategy for the bacteria Faecalibacterium prausnitzii, recognized for their anti-inflammatory activities intestinal …
Synthesis of mesoporous silica nanoparticles (MSNs) and encapsulation of cisplatin for targeted cancer therapies
2014
The aim of this PhD thesis is to elaborate mesoporous silica nanoparticles (MSNs) able to sustain the release of cisplatin into the intracellular compartments of solid tumors. The parametric study shows that morphological, structural and textural properties of MSNs-MCM-41, synthesized by sol-gel reaction by using TEOS as a silica source and CTAB as a structure-directing agent, depend on pH, stirring speed, temperature and extraction process of CTAB. The synthesis atmosphere has to be controlled in order to avoid the presence of ethanol and carbonate species which are responsible of necks between particles generating unstable suspensions of MSNs.MSNs were functionalized in order to control t…